Сентябрь 2021 г.

Российская наука и мир (по материалам зарубежной электронной прессы)

CONTENTS / ОГЛАВЛЕНИЕ


• Medieval Russians hid silver hoard before Mongol invasion
• A human mission to Mars should last a maximum of 4 years
• The woolly mammoth’s return could thaw relations with Russia
• Archaeologists discover remains of 10,000-year-old settlement in Russia
• Cooling PV panels with water and cotton mesh
• The Greek archaeologist who discovered Alexander’s city of Bactria
• These scientists want to bring back the woolly mammoth. Ethicists aren’t so sure
• NUST MISIS and MSU scientist synthesize new spin liquid candidate
• A new eco-friendly and sustainable algae-based way to fight water pollution
• A record number of Atlantic walruses recorded in the Russian Arctic
• Un mauvais goût de plastique dans les eaux du lac Baïkal
• "Hard" science provides no salary advantages compared to "soft" science at any career stage
• Russian scientists achieve 21.1% efficiency in perovskite solar cell via Mie-resonant silicon nanoparticles
• New optical "transistor" to speed up computation up to 1,000 times, at lowest switching energy possible
• Russian scientists use supercomputer to probe limits of Google’s quantum processor
• Bronze age bull geoglyph found in Siberia is a first

Недалеко от Старой Рязани, уничтоженной в 1237 году во время нашествия Батыя, сотрудники Института археологии РАН обнаружили клад, состоящий из серебряных слитков и разнообразных украшений. При этом причиной прятать сокровища стало вовсе не вторжение монголов, поскольку клад был зарыт более чем за 100 лет до гибели города.

Archaeologists in southwest Russia have unearthed a trove of medieval silver at a site where treasure was often hidden from an invading Mongol army in the 13th century - but oddly it seems to have been buried there at least 100 years before the Mongols swept through.
The trove of silver pendants, bracelets, rings, and ingots was found during excavations earlier this year near the site of Old Ryazan, the fortified capital of a Rus principate that was besieged and sacked by Mongols in 1237. The Mongol attack was particularly bloodthirsty; historical accounts report that the invaders left no one alive in Old Ryazan and archaeologists have discovered nearly 100 severed heads and several mass graves there from the time. The hidden treasure was found in the forested bank of a ravine several hundred yards away from two small medieval settlements that had existed there; archaeologists also found remains of a cylindrical container probably made from birch bark that had once held the trove, according to a translated statement from the Russian Academy of Sciences.
The treasure includes 14 ornate bracelets, seven rings and eight "neck hryvnias" - a type of pendant worn around the neck that gave its name to the modern Ukrainian currency - and weighs 4.6 pounds (2.1 kilograms). The jewelry is finely made, and archaeologists think its mixed composition shows it was a trove of accumulated wealth rather than a set of jewelry for a particular costume.
Golden Horde
Ryazan was one of several medieval principalities of the Rus people in the 11th century. It was centered on the city now known as Old Ryazan - about 30 miles (50 km) southeast of the modern city of Ryazan and about 140 miles (225 km) southeast of Moscow - and grew powerful enough to occasionally go to war with its neighbors. But Ryazan was east of the other Rus principalities, and so it was the first to fall to an invading Mongol army from the far east, led by a grandson of Genghis Khan called Batu Khan. The Mongols first defeated the Ryazan army in battle and then besieged the capital city, using catapults to destroy its fortifications. The inhabitants of the city repelled the besiegers for almost a week - but in the end the Mongols plundered the city, killed its prince, his family, and its inhabitants, and burned all that remained to the ground. A Rus chronicler noted "there was none left to groan and cry."
Batu Khan's armies went on to conquer and subjugate other Rus principalities until the Mongol leader's death in 1255; his successors ruled much of southern and central Russia as the Golden Horde - from the Turkic phrase "Altan Orda," which means "golden headquarters," possibly from the golden color of Batu Khan's tent.
The hidden hoard of medieval silver, including several finely-made bracelets, was found at the site of Old Ryazan which was destroyed by an invading Mongol army in the 13th century. Archaeologists say the silver bracelets and other items of jewelry in the medieval hoard are especially well-made.
Among the treasure are several "seven ray rings" that are thought to represent the rays of sun. Seven-ray rings became a distinctive feature of early medieval Russian jewelry; it's thought their design was introduced from the far east.
Some of the bracelets, including this one of braided silver wire, are thought by their style to date from the 10th and 11th centuries. The ends of some of the bracelets are hollow and delicately embossed with intricate ornamental designs, including stylized palm trees that suggest an eastern and southern influence. Some of the bracelets are embossed at the ends with crosses that presumably portray Christian crucifixes.
Several buried treasures found at Old Ryazan date from the siege of city in 1237, but archaeologists think this hoard of silver was buried about 100 years before that.
Hidden treasure
The practice of hiding treasure to prevent the invading Mongols from finding it seems to have been relatively common during the siege - more than a dozen hidden troves have now been found nearby, including the famous Old Ryazan Treasure, a collection of bejeweled royal regalia which was discovered by chance in the 19th century and is now on display in a nearby cathedral.
Somewhat surprisingly, however, the newly-discovered trove seems to have been hidden away between the end of the 11 century and the beginning of the 12th century - a century before the Mongol invasion, based on analysis of the style of the jewelry and ceramics found nearby, the RAS archaeologists said.
"The… treasure is clearly older than the Old Ryazan Treasure and includes jewelry made with simpler techniques and a more archaic manner," the statement read.
The trove includes several six-sided "grivna," a relatively small type of standardized silver ingot that could be used as jewelry, a measure of weight, or currency during the medieval Rus period. The bracelets are especially well made. The most complex have three silver braids and are ornamented at the ends with embossed crosses and palm leaves, the archaeologists said.
"Further studies of the treasure items, the technique of their manufacture, the composition of the metal will complement our knowledge of the early history of Old Ryazan," they wrote; "possibly it will reveal the historical context of the concealment of the treasure."

День, когда человек отправится на Марс, не так уж и далек. Но перед этим необходимо решить ряд вопросов, один из которых - воздействие космической радиации. Международная команда ученых из России, Германии и США пришла к выводу, что наилучшим временем для отправки миссии на Красную планету будут 6-12 месяцев после пика солнечной активности, а сама миссия не должна превышать 4 года.

At one time, the idea of sending humans to Mars either seemed like a distant prospect or something out of science fiction. But with multiple space agencies and even commercial space companies planning to mount missions in the coming decade, the day when humans will go to Mars is fast approaching the point of realization. Before this can happen, several issues need to be resolved first, including a myriad of technical and human factors.
In any discussion about crewed missions to Mars, there are recurring questions about whether or not we can mitigate the threat of radiation. In a new study, an international team of space scientists addressed the question of whether particle radiation would be too great a threat and if radiation could be mitigating through careful timing. In the end, they found that a mission to Mars is doable but that it could not exceed a duration of four years.
The research was led by Mikhail Dobynde, a researcher from the Skolkovo Institute of Science and Technology and the Russian Academy of Science in Moscow. He was joined by members from the GFZ German Research Centre for Geosciences at the Helmholtz Centre Potsdam in Germany, the University of California Los Angeles (UCLA), and the Massachusetts Institute of Technology (MIT).
For the sake of their study, the team considered the threat posed by the two main types of radiation sources: Solar Energetic Particles (SEP) and Galactic Cosmic Rays (GCR). The former consists of fast-moving protons, electrons, and high-energy atomic nuclei that can negatively affect electronics and living tissue. The latter consists of the same range of energetic particles but originate beyond the Solar System and are attributed to supernovas.
The intensity of both of these radiation sources depends on the level of solar activity, where SEP levels are least intense during a solar minimum, but GCR activity is most enhanced. The reverse is also true, where GCR activity will be lowest during solar maximum, but SEP will be elevated. To gauge the threat posed by these sources, the team combined geophysical models that considered how particle radiation varies during the 11-year solar cycle.
These were combined with models of how radiation will affect human passengers (including different bodily organs) and their spacecraft. The team then ran a series of Monte-Carlo simulations of radiation propagation that took into account 10 different types of SEP radiation and 28 types of fully-ionized GCR elements. From this, they determined that the best time to send a Mars-bound mission would be during the six to twelve months after solar activity peaks (aka. solar maximum).
At this point, GCR activity is at its lowest, and SEP begins to decrease from its highest intensity. The situation slowly reverses during the next six and a half years, with GCR activity slowly increasing until it reaches maximum intensity (coinciding with a solar minimum). Given that the average flight time to Mars is about nine months, a crewed return-mission to Mars could be done in less than two years. According to their findings, Dobynde and his colleagues found that this would ensure that the mission made it home before the radiation environment became too hazardous. But a mission that lasted up to four years would be pushing it since they would be forced to return home amid higher levels of GCR activity. Hence, their modelling also indicated that the spacecraft’s shielding would need to be relatively thick to ensure the crew’s health.
However, these same results also indicated that having shielding that is too thick might actually increase the amount of secondary radiation to which the crew is exposed. This phenomenon, where high-energy particles collide with shielding to produce a cascade of secondary particles (aka. a "particle shower"), has been studied extensively aboard the International Space Station (ISS).
According to Yuri Shprits, the head of space physics and space weather at GFZ Research Centre for Geosciences (and a co-author on the paper), these results could be of great value to future mission planners. "This study shows that while space radiation imposes strict limitations on how heavy the spacecraft can be and the time of launch, and it presents technological difficulties for human missions to Mars, such a mission is viable," he said.
These considerations are vital given that there are multiple plans to conduct regular missions to Mars in the near future. This includes NASA and its Moon to Mars mission architecture, China’s plans to send crews to Mars by 2033 (and build a permanent research outpost there), and Elon Musk’s plan for sending payloads and crew every two years using the SpaceX Starship and Super Heavy launch vehicle.
These are just a few of the visions for Martian exploration (and settlement) that have been articulated of late. With all of the robotic missions currently exploring the planet and the possibility of human exploration on the horizon, Mars is looming in the public imagination once again. Since the Apollo era, Mars has come to be viewed as the "next great leap" that could lead to a new era reinvigorated space age!
The fact that Mars is the most habitable celestial body beyond Earth has also been a source of inspiration to scientists, mission planners, astronauts, and futurists alike. Despite the challenges that going there would entail, there is currently no shortage of people willing to sign-up for a one-way trip. For these adventurous souls, the prospect of breaking ground on Mars - the next great "frontier" - has a certain romance to it.
But what is especially exciting is when realistic appraisals show that these adventurous notions are actually feasible, given the right preparations, technology, and mitigations strategies. When scientific fact and romance come together to make plans for the future, great things can happen!

На фоне натянутых российско-американских отношений шанс на сотрудничество дает один весьма амбициозный научный проект - возрождение шерстистого мамонта. Гарвардский генетик Джордж Черч надеется в сотрудничестве с сибирскими учеными («Плейстоценовый парк» Сергея и Никиты Зимовых) в ближайшие двадцать лет выпустить на просторы Арктики стадо животных, практически неотличимых от мамонтов ледникового периода.
Проект дает уникальные возможности для сотрудничества в области климатических изменений и арктической политики. Эти проблемы, имеющие большое значение как для России, так и для США, выходят за рамки национальных границ, а значит, для их решения потребуется межгосударственное сотрудничество.

Even under a new U.S. administration, U.S.-Russian relations are chilly at best. U.S. President Joe Biden and Russian President Vladimir Putin came away from their eagerly anticipated June summit having agreed on little more than nuclear war should never be fought. As diplomatic negotiations go, agreeing that nuclear Armageddon should be avoided is a modest accomplishment.
Since then, there has not been much room for optimism; in August, Russia moved forward with plans to ban foreign nationals from staffing the U.S. Embassy and consulates in Russia, cutting mission personnel from upward of 2,200 people to around 120 people. Meanwhile, Russian actors appear undeterred in their efforts to wage damaging hacking campaigns against a broad range of U.S. targets, despite Biden’s demands in June that Putin rein in these ransomware attacks.
But amid many otherwise dim diplomatic prospects, one hope for warmer ties and improved strategic stability may come from a most unexpected source: the woolly mammoth.
Whimsical though it may sound, serious efforts are under way in Harvard Medical School’s labs by revered geneticist George Church to resurrect the mammoth from extinction. Working in collaboration with Russian scientists in northeastern Siberia and a team of conservationists in California, Church hopes to release a herd of creatures that are effectively indistinguishable from Ice Age woolly mammoths within the next two decades.
The woolly mammoth revival project creates unique opportunities for bilateral cooperation in the arenas of climate change and Arctic policy. These issues transcend borders and have serious, growing impacts on the internal affairs of both Russia and the United States. And dealing with them will require interstate cooperation - regardless of which other political squabbles may color relations between Moscow and Washington. If successful, the woolly mammoth revival project could change the tenor of the Arctic itself - turning it into a venue for cooperation rather than all-out competition.
Although the Cold War is often framed in terms of technological competition between Moscow and Washington, science often offered fertile ground for cooperation between the two adversaries. This was true even during the lowest of bilateral lows. Particularly fruitful avenues of cooperation have included joint U.S.-Soviet efforts on human space flight as well as bilateral efforts on vaccine diplomacy and joint efforts during Operation Breakthrough to rescue a group of gray whales trapped by sea ice off the Alaskan coast. Like climate change, these are transborder issues. For that reason, they stand to benefit from coordinated international solutions.
Enter the woolly mammoth. The primary goal of Church’s project is to turn back the hands of time on the Arctic tundra and restore the grasslands of the Pleistocene era. Within the next 20 years, he plans to release these lab-bred mammoths into Pleistocene Park, a sprawling nature reserve in northeastern Siberia run by Sergey and Nikita Zimov, a respected father-son research team. The Zimovs have already successfully rewilded several species that formerly inhabited these northern grasslands, such as the musk ox and plains bison.
As the Pleistocene epoch drew to a close, woolly mammoths and other large grazing animals that once populated the northern steppe disappeared. Grasses and herbs that previously sustained the herds of the mammoth steppe gave way to less productive types of flora, such as slow-growing mosses, shrubs, and larch trees. Lumbering across the landscape, large herbivores previously played a key role in compacting and dispersing layers of snow. In the absence of these species, the frigid temperatures of northern winters are less effective in penetrating the soil than they once were. This, paired with warmer summer temperatures, threaten to speed up the melting of the region’s permafrost, which, in turn, will accelerate the release of methane. The degradation of the Arctic permafrost threatens to release some 1,400 gigatons of methane into the stratosphere, which would be catastrophic from a climate change perspective given methane’s potent warming qualities. "That would be an extremely inconvenient truth because it dwarfs the 10 gigatons per year that all humans use and abuse combined," Church said.
Research conducted by Church, the Zimovs, and others suggests the reintroduction of grazing species, even many millennia after they vanished from these parts, can play a key role in restoring historic grasslands. The reintroduction of grasslands to these regions is expected to foster greater biodiversity, allowing large herbivores to flourish. In turn, large grazing animals will compact the soil, enabling the permafrost to freeze more deeply during winter months. Woolly mammoths add particular value in this regard. According to Church’s team, they were considered to be engineers of the grasslands in their day, preventing the growth of trees that would break up the grasslands and thereby compromise their natural ability to sequester carbon from the atmosphere. In addition, the mammoths dispersed massive quantities of nutrients across vast swaths of land by way of their fecal matter.
Asked why he chose the woolly mammoth as the mascot of his de-extinction project, Church said the creature offered considerable promise in terms of mitigating climate change risks given the impact of methane on warming while also being public relations-friendly enough to be a viable choice. "They are large and charismatic and could win a popularity contest, but they’re also vegetarian. We didn’t want to bring back the T-Rex," he explained.
In recent years, other teams of researchers, including most prominently a group in South Korea, generated buzz about the prospect of cloning the mammoth. At present, however, this option does not appear to be viable because it would require the recovery of living cells. This is an obvious problem, as mammoths went extinct thousands of years ago.
Church’s team has not confronted this obstacle. He is working with CRISPR-Cas 9, a gene-editing technology that enables scientists to alter a creature’s genetic materials by cutting targeted strands of DNA and either adding or deleting genetic materials to change the overall DNA sequence. By enabling scientists to physically alter the structure of a creature’s genome, this technology offers hope for everything from disease prevention to - as in the case of Church’s project - altering the characteristics of living species.
Church’s team is years into the process of splicing together the DNA of woolly mammoths with that of Asian elephants, the mammoth’s closest living relative. The goal is to create a novel breed of hybrid mammoth-elephants that are cold-resistant, virus-resistant, and poacher-resistant. To achieve the latter, Church has genetically modified their tusks to be short and thus unprofitable for hunters. After years of pioneering work on the project, he estimates his team is approximately 40 genetic adjustments away from successfully engineering a cell that can be used to create the embryo of the first new woolly mammoth.
Once the genetic engineering portion of this project is complete, a key obstacle to reintroducing the mammoth to the wild will be ensuring efficient population growth. To spawn new mammoths - initially without hampering Asian elephant conservation efforts and then ensuring the efficient proliferation of the resurrected species - Church plans to rely on in vitro birth technology. This is not to be mistaken with in vitro fertilization, where an embryo is created in a lab setting. In in vitro birth, an artificial womb is used to actually develop the fetus from embryo to baby.
Given how long it will take to nail down all of these emerging technologies, Church estimates mammoths will be hard at work restoring the grasslands in some 16 years. At that point, the reproductive efforts of this initial population will continue to be supplemented by in vitro development efforts in the lab.
To be sure, the idea that we’re just 16 years away from seeing woolly mammoths roam their ancestral lands will sound farfetched to many. But Church is known for making the impossible happen. As science journalist Torill Kornfeldt describes in her book The Re-Origin of Species: A Second Chance for Extinct Animals, "People would call [Church] an incurable, almost crazy, optimist, if it weren’t for the fact that all the scientific progress he predicted has actually come true. And in many cases, it’s actually happened in his own lab." In addition to his de-extinction efforts, Church is known for his pioneering work in genome sequencing and synthetic biology.
And between the genetic work his team has already carried out and the successful rewilding efforts that already took place in Pleistocene Park, Church is confident this project will be a success.
Scientific research on genetic engineering has bounded ahead in recent years. But it’s been accompanied by a lack of clear policy guidance. At present, international laws and standards governing the de-extinction on animal species are scant. The authors of a 2017 study on de-extinction policy explain that "it will be crucial to clarify how de-extinct species will be classified, in particular, in relation to their potential conservation status under national and international law. … As the de-extinction debate is relatively recent, [de-extinct animal species] are currently not explicitly considered in legislation."
But it is precisely within these legal gray areas that Washington and Moscow have successfully managed to cooperate, even during previous diplomatic nadirs. In particular, the two countries have a history of working together on matters of compelling mutual interest with respect to then-ungoverned territories. This is evidenced by Antarctic and space demilitarization treaties, both of which were enacted during the Cold War.
The Arctic, lacking a central governing international treaty or body, is riddled with governance gaps, including - according to a recent RAND Corporation report - "limited dialogue and transparency on military issues, limited capability to execute governance agreements, and tension between the growing need for inclusivity and Arctic states’ interests."
But there is room for optimism. As Church noted: "One of the nice things about science, as long as it’s not required for national defense, it tends to be very sharing and cooperative - it sometimes cuts through points where diplomacy is not cutting through. Very often you can have a scientific conference, even if the nation states are at each other’s throats."
Buoyed by such sentiments, Church, the Zimovs, and their respective teams are forging ahead despite the lack of clear governing policy. The latter would be easy enough to develop. This is a rare, low-stakes opportunity for diplomats to forge an agreement that is beneficial to all, and thus, both sides of the widening U.S.-Russia divide can sign off on it with minimal political costs. Furthermore, it’s a project that captivates the imagination and is ripe with opportunities for cultural diplomacy on both sides.
Evidence of the two governments’ views on this specific revival project are scant, which could owe to the fact it would be nearly impossible to predict at this point precisely when, where, and how the mammoths will be released into the wild. The de-extinction process could hypothetically be governed by a patchwork of environmental, species protection patents and other laws. For example, in the United States, the release of genetically engineered organisms into the wild would trigger an environmental impact analysis under federal law and likely additional scrutiny under state law, and it may also have patent implications. This could all be further complicated by the process through which the mammoth de-extinction project transitions from private labs to the public sphere. Given the scores of variables at play, policymakers could be forgiven for taking a wait-and-see approach.
But international governance on this matter is a goal it would behoove all to work toward; Russia’s prolific track record of unexpectedly weaponizing certain finicky species - including dolphins and cockroaches - injects a compelling motive for cooperation on the U.S. side. The last thing the United States wants is woolly mammoths trained for combat operations.
Ultimately, climate change is coming for us, and none of the world’s great powers can afford to fight this battle alone. Desperate diplomatic times call for imaginative measures. The United States and Russia have an established history of stubbornness, and neither side has much to win from caving on political squabbles at this point. But the two countries also have a rich history of scientific cooperation through even the bleakest foreign-policy eras. The woolly mammoth revival project may harken back to ancient history, but it offers a concrete path toward joint action on climate change - an issue that will only grow more present with time. And it just may earn some smiles in the process.

Во время раскопок возле реки Велетьмы (Нижегородская область) сотрудники Института археологии РАН обнаружили следы поселения возрастом около 10 тысяч лет и более 20 тысяч различных артефактов, в том числе принадлежащих и более поздним эпохам.

Archaeologists have excavated traces of Mesolithic settlements near the Veletma River in Russia, according to Heritage Daily.
The Institute of Archaeology of the Russian Academy of Science has found settlements that date from roughly 10,000 years ago during the early stages of the Butovo culture, described as the communities of Mesolithic hunter-gatherers that occupied the upper catchment area of the forest zone in Western Russia during this period. The Mesolithic period took place between 10,000 BCE and 8,000 BCE and is otherwise identified as the Middle Stone Age.
The mesolithic activity was first identified during the 1970s and 1980s, however, this is the first time that a systematic excavation has been conducted. Archeologists studied five sites: Maloye Okulovo - 10, Maloye Okulovo -11, Maloye Okulovo -19, Maloye Okulovo - 20 and Malookulovskaya - 3. This area covers more than 10,000 square meters. Objects of later areas from the Neolithic, Bronze, and Early Iron ages were also revealed. At site Malookulovskaya-3, a possible dwelling was discovered. This, and findings at Maloye Okulovo -11, Malookulovskaya-3 and Maloye Okulovo -19 suggested possible seasonal Mesolithic sites, indicating hunting and fishing by the accumulation of flint artifacts and a large number of animal and fish bones.
The team discovered various flint artifacts including scrapers, arrowheads, punctures, and fragments of an ax at almost all the sites. Maloye Okulovo-19 featured a large accumulation of waste from flint production. This suggests that this site was the center for manufacturing weapons and tools.
Konstantin Gavrilov, head of the Navashinsky detachment of the IA RAS said, "The finds near Maly Okulov fit into the characteristics of the Butovo archaeological culture, which was widespread at that time in the Volga-Oka interfluve. Having received an accurate description of the finds and an understanding of the technology, we will be able to compare the features of this Mesolithic culture with objects from earlier, and later periods of human history and reconstruct technological progress."

В Уральском федеральном университете разработали метод охлаждения солнечных панелей сразу с двух сторон с помощью ПВХ-трубки и хлопчатобумажной сетки. Система минимизирует потерю воды и повышает эффективность работы панели.

A group of Russian researchers has developed a new active technique to reduce the operating temperatures of solar modules that acts simultaneously on both sides of a panel.
The system, dubbed "dual surface cooling" by the scientists, is built with a 16 mm single polyvinyl chloride (PVC) perforated pipe applied on the upper part of the module that spreads water on the front and the rear surfaces and a cotton wick mesh that is applied on the rear surface and collects the water and spread it down the rear surface itself.
"One issue that this study minimizes is the loss of water through evaporation through the covering of the back surface of the panel with aluminum sheet which is also strategically perforated to allow the flow of air into the inner section of the enclosed area," the academics explained. "This approach does not totally prevent the loss of water but minimizes its loss especially at the rear section of the panel."
The water is provided by a tank that is placed at a height higher than the PV panel allowing the free flow of water to the module using gravity. A pump, however, is needed to pump the water back into the tank. The aluminum sheet captures the evaporating water and conveys it to a basin that is fixed beneath the PV panel, and this water is then recycled into the water tank to be reused. "Holes were created in the aluminum sheet in order to allow some level of air exchange in the inner section of the panel and the ambient air," the Russian group highlighted.
The technique was tested on two panels with a size of 95×45 cm, an output of 30 W, and a tilt angle of 45 degrees each. The thermal imager Testo 875 was used to take infra-red thermal images for both panels during mid-day and a GM 1362-EN-01 temperature thermometer and 14 K-type thermocouples were utilized to measure the panel temperature. The performance of the system was compared to that of a reference system with no cooling system applied.
The measurements showed that the cooled system achieved an average temperature of 35.72 degrees Celsius while the uncooled one reached 59.27 degrees Celsius. Furthermore, the cooled panel had an average power and voltage of 18.53 V and 13.03 W compared to 16.71 V and 10.00 W for the uncooled system. "Similarly, the cooled PV module recorded an average efficiency of 14.36% against 12.83% for the uncooled panel. This represents a difference of 1.53% which is an 11.9% improvement in the efficiency of the cooled panel," the researchers emphasized.
"The system was tested in a real environment but we haven't evaluated the economics of the cooling mechanism," researcher Ephraim Bonah Agyekum told pv magazine. Looking forward, the research team wants to add sieves to the basin beneath the panel to filter out dirt and to consider the effect of flow rate on the performance of the module.
The system is described in the study "Effect of dual surface cooling of solar photovoltaic panel on the efficiency of the module: experimental investigation," which was recently published in Heliyon.

Статья посвящена советскому и российскому археологу греко-понтийского происхождения Виктору Ивановичу Сарианиди (1929-2013). Ему, ставшему легендой еще при жизни, принадлежат два величайших археологических открытия XX века: «золото Бактрии» - некрополь Тилля-Тепе на севере Афганистана, где было обнаружено около 20 тысяч золотых предметов, и храмовый город Гонур-Депе на территории современного Туркменистана, крупнейшее поселение ранее неизвестной Маргианской цивилизации.

Prominent Russian archaeologist of Greek-Pontic descent Victor Sarigiannidis is the man who discovered the ancient city of Bactria. Sarigiannidis has been described as a "poet of archeology," "the man who walked in the steps of Alexander the Great in Central Asia" and a "hero of Pontian Hellenism". The Greek archaeologist spent decades in the deserts of Turkmenistan and Afghanistan, where he brought to light entire cities with wonderful culture and wealth.
Discovery of Bactria
With the discovery of Bactria and the findings of the necropolis of Gonur Tepe, Victor Sarigiannidis proved that Hellenism spread in the area 1,600 years before the campaign of Alexander the Great. The evidence supports the theory of the connection of the culture of Oxus River with the Minoan-Mycenaean culture. At the same time, he developed the theory that Zoroastrianism first appeared in this area in palaces and altars accompanied by signs of fire worship.
Life and Work of Victor Sarigiannidis
Victor Sarigiannidis was born on September 23, 1929 in Tashkent - then Soviet Union, now Uzbekistan - to Greek parents. In 1952 he graduated from the Central Asian State University (Tashkent) and in 1961 received a master’s degree in Near and Middle Eastern Archeology from the Moscow Institute of Archeology. From 1949 and on he played an active role in archaeological excavations in Central Asia and Afghanistan. There, he brought to light the Royal Necropolis of Tilia Tepe (1st century AD).
In Tilia Tepe, more than 20,000 gold objects were found. This was considered the "discovery of the century." The findings were housed in the State Museum of Afghanistan. However, during the wars in the area, all the findings were stolen between 1991-1993 and since then their whereabouts are unknown.
The findings in the "golden tomb" proved the existence of cultural influences from various regions such as Greece, Iran, India, Egypt, China and Siberia. For example, Aphrodite with wings and a dot on the forehead is one of the elements that revealed a wide meeting of cultures, such as Greek, Indian and local that worshipped winged deities.
The Hellenistic kingdom of Bactria - or Greco-Bactrian Kingdom as historians call it - flourished in the area for two centuries after the death of Alexander the Great.
In the last 30 years of his life, Victor Sarigiannidis made the largest archaeological excavations in the Karakum Desert in Turkmenistan. There he discovered the Margian Kingdom (end of the 3rd millennium BC) completely unknown to the international scientific world.
The Greek archaeologist introduced a new theory to the formation of the early Hellenistic culture in Central Asia and the existence of a culture identical to that of Bactria, which is also associated with the Minoan-Mycenaean culture.
Overall, Sarigiannidis contributed decisively to the emergence of elements of Greek culture in the wider Black Sea region and also to the discovery of Greek roots in present-day Afghanistan, Turkmenistan and Uzbekistan. With his findings, Victor Sarigiannidis proved that Hellenism spread to the East and Central Asia 1,600 years before the campaign of Alexander the Great.
Honors and disappointment with the Greek State
For his work, Sarigiannidis was awarded the title of Doctor of Historical Science from the Russian Academy of Sciences in 1975.
He was an honorary member of the Hellenic Anthropological Society, a member of the American Society of Sciences and a member of the Russian Federation of Journalists.
In Greece, Victor Sarigiannidis, received Greek citizenship in 1997 and was awarded with the Golden Cross of the Order of Honor of the Hellenic Republic in January 2002.
He also received Honorary citizenship of Turkmenistan in 2000, was awarded the
Makhtumkuli International Prize in Turkmenistan in 2001 and the Jamal ad-Din al-Afghani prize, the highest cultural honor of Afghanistan.
His writing was particularly rich, with 20 books in Russian, which have been translated into English, German, Japanese and Greek. More than 200 of his articles have been published in prestigious international scientific journals.
Coming to Greece in the mid-1990s, he received many promises from the Greek state for financial support in order to continue his work, but he was disappointed by the behavior and indifference of those in charge.
Later, the promises of then prime minister Kostas Karamanlis (2004-2009) were never kept. In 2005, after years of efforts, he received a meager pension from the Greek state, amounting to 192 euros per month.
Victor Sarigiannidis died in Moscow on December 23, 2013, at the age of 84.

Намерение компании Colossal в сотрудничестве с российскими учеными создать «морозоустойчивого слона со всеми основными биологическими характеристиками шерстистого мамонта» с целью восстановить тундровую экосистему и остановить таяние вечной мерзлоты, ожидаемо вызвало много вопросов. Этичность модификации генов, проблема инвазивности вида, наличие ресурсов для дальнейшей жизни «мамонтов», наконец, их соседство с людьми, которых сейчас гораздо больше, чем 10 тысяч лет назад.

When ethicist Karen Wendling of Canada’s University of Guelph first heard about a new company’s plan to "de-extinct" the woolly mammoth, she was enthralled by the possibilities it created.
If a behemoth similar to the one that roamed the Earth 4,000 years ago could be engineered, could a dodo bird and other long-gone species, as well?
"Who doesn’t think it’d be cool in principle," she said. "It also sounds a lot like ‘Jurassic Park’".
A start-up, Colossal Laboratories & Biosciences, made headlines earlier this week when the company announced an ambitious plan to create a "cold-resistant elephant with all of the core biological traits of the woolly mammoth." The scientists behind the initiative say their work could help reverse the effects of climate change and advance genetic engineering.
But their idea has also generated a fierce ethical debate, not unlike the one that played out on movie screens years ago: Is this another case where scientists were so preoccupied with whether they could that they didn’t stop to think if they should?
"I’m quite leery of a technological fix for the problems we’ve created," Wendling said.
Colossal, which has received at least $15 million from investors, has set out to edit the Asian elephant’s DNA, inserting traits from the woolly mammoth. Then, using the same process that created Dolly the sheep, the first mammal successfully cloned from an adult cell, scientists aim to create a hybrid woolly mammoth-Asian elephant embryo.
A surrogate African elephant would carry the embryo for a gestation period of nearly two years. The company is also working on the possibility of creating artificial wombs.
Colossal aims to have something similar to a woolly mammoth calf within the next six years. Company leadership acknowledges that the timeline is ambitious.
Ben Lamm, CEO of Colossal, told The Washington Post in an email that the extinction of the woolly mammoth left an ecological void in the Arctic tundra that Colossal aims to fill. The eventual goal is to return the species to the region so that they can reestablish grasslands and protect the permafrost, keeping it from releasing greenhouse gases at such a high rate.
"We believe our work will restore this degraded ecosystem to a richer one, similar to the tundra that existed as recently as 10,000 years ago," he said.
Colossal’s board is made up in part of biologists and bioethicists, and renowned geneticist George Church is at the front of the company’s mammoth push. The project also hopes to "de-extinct" other species and create an inventory of genetic material from endangered species.
Church said in an email that Colossal is most interested in preventing the loss of endangered species like the Asian elephant through genetic variation.
He also said this "Arctic elephant" was chosen for the project partly because it is easy to track, adding that the Asian elephant is "arguably the most charismatic endangered species."
Christopher Preston, a professor of environmental ethics and philosophy at the University of Montana, questioned Colossal’s focus on climate change, given that it would take decades to raise a herd of woolly mammoths large enough to have environmental impacts and there are tried-and-true conservation tactics that need funding.
"We should be making sure those get enough resources, rather than getting taking our eye off the ball by the distraction of a project such as de-extinction," he said. "It's very hard for me to think that the idea you could de-extinct a woolly mammoth is a technological fix for anything that needs fixing in the next century."
But Beth Shapiro, an investigator at the Howard Hughes Medical Institute, professor at University of California at Santa Cruz and author of "How to Clone a Mammoth: The Science of De-Extinction," said as flashy as the idea of bringing back a mammoth is, this endeavor is exciting because it doesn’t stop there.
Shapiro said the investments made in this project could create technologies to help living species adapt to climate change by editing their genes to include more resilient traits. This is critical because animals can no longer evolve as quickly as their habitats do. She said the thought of bringing the mammoth back to stomp across the Earth has also drawn in massive donors who likely would not have thrown their money toward more traditional methods.
Though Wendling was also initially excited by the idea, later she thought about groups of woolly mammoths wandering through Russia, Alaska and Canada and wondered what the tundra’s Indigenous people would think of the effort.
The tundra wasn’t nearly as populated with humans when woolly mammoths roamed the earth, she noted, and it’s difficult to predict what actual effects reintroducing them would have on the environment.
Lamm said no Indigenous populations will be affected by Colossal’s initial reintroduction plans, which will begin in Pleistocene Park, a nature reserve in Siberia. He said while the company is several years off from beginning the "rewilding" process, "we are already starting conversations with several indigenous leaders in various northern regions."
Paul Thompson, W.K. Kellogg Chair in Agricultural, Food and Community Ethics at Michigan State University, said while research like this could help move the science forward and ignite the imaginations of those watching it unfold, it also seems frivolous.
He said there should be a high ethical bar when considering gene modification, and pointed to the controversy over the modification of plants, which prompted calls to label all foods containing genetically modified organisms or GMOs. He questioned whether creating a new species of "quasi-mammoths" is in the interest of the animals that would be created.
Thompson said biologists are still trying to uncover what makes some species invasive and others helpful to a new ecosystem, and said there’s a conversation to be had about whether introducing a woolly mammoth equates to introducing an invasive species.
Shapiro said while there will be no shortage of ethical and technical challenges facing Colossal’s project, she’s thrilled by the amount of interest in it and what that could mean for conservation more broadly.
"We’re not going to start making any progress until we stop wringing our hands, about the potential risks and really concentrate on the potential rewards," she said.

Исследователи из МГУ имени М.В.Ломоносова и НИТУ «МИСиС» синтезировали новый материал со свойствами спиновой жидкости, редкого состояния вещества, при котором спины отдельных атомов не замерзают даже при самых низких температурах. Такие материалы могут использоваться в квантовых технологиях, основанных на перепутывании волновых функций отдельных частиц.

Russian scientists have synthesized a new material that exhibits the properties of spin liquid, an extremely rare phase of matter that arises in frustrated quantum magnets at low temperatures. Such materials could be used in quantum technologies based on the entanglement of the wave functions of individual particles. The study was published in the Journal of Inorganic Chemistry.
Spin, the intrinsic angular momentum associated with the electron, is a universal property of elementary particles. Many materials have disordered and moving particle spins at room temperature and only freeze and become organized as the temperature decreases.
Quantum spin liquids are materials that display no magnetic order, even at the lowest temperatures. Scientists have speculated their existence since the dawn of quantum mechanics but have only recently begun to search for such material.
The mineral Herbertsmitite has copper ions as carriers of the magnetic moment that form a perfect two-dimensional kagomé lattices (kagomé is the pattern of Japanese wicker ware with a hexagonal motif). Until now, it has been considered as a prime candidate for the realization of quantum spin liquid. Now Russian scientists have added another substance to the list of materials potentially possessing spin liquid properties.
Researchers from Lomonosov Moscow State University and NUST MISIS have synthesized a new sodium bismuth oxo-cuprate phosphate chloride with a square-kagomé-type lattice which exhibits no magnetic ordering or spin freezing when cooled to -271°C. The researchers have therefore hypothesized that the material's spin subsystems exhibit spin liquid -like behavior at low temperatures.
"Two main periodic fragment modules can be distinguished in the crystal structure of the spin liquid candidate. The first one is the layers formed by clusters of four tetrahedrons. There are oxygen atoms in the centre of each tetrahedron. Three vertices of the tetrahedron have copper atoms and the fourth has a bismuth atom. Such layers carry a positive charge and are ready to share it with the second, negatively charged fragment," said Alexander Vasiliev, one of the authors of the research, Head of the Functional Quantum Materials Laboratory at NUST MISIS.
According to Prof. Vasiliev, the second layer is combined of polyhedrons containing sodium, phosphorus and copper atoms in the centres and oxygen and/or chlorine atoms in the vertices.
"The nature of the described layers can be viewed as a 'host-guest' model. Curiously enough, the new compound was obtained with an excess of cooking salt! The salt contributed to the formation of the matrix - the 'host' that welcomed the 'guest' fragment of the composition to form a material with unique physical characteristics," Alexander Vasiliev explained.
He further added that the material could find future applications in quantum technologies based on the entanglement of the wave functions of individual particles.

Международная команда ученых, в том числе российских (Объединенный институт высоких температур РАН и РУДН), разработала экологичную технологию очистки сточных вод на основе биоремедиации водоросли Pseudochlorella pringsheimii.

Our ever-growing demand for freshwater has caused its sources to diminish rapidly and scientists have been attempting to find strategies to purify wastewater for reuse to meet future demands. At present, the most common wastewater treatment techniques involve the use of chemicals or ultraviolet radiation to kill microorganisms or remove pollutants. But these conventional techniques have several drawbacks, such as the toxic effects of chemical substances on our health or the high energy requirements to run treatment facilities. To create a sustainable system of wastewater treatment, the focus has shifted to eco-friendly and cost-effective technologies.
One such technology under exploration involves using aquatic microorganisms, such as algae, which are known to be able to degrade complex molecules. Recently, a team of scientists from India (Algae Research and Bioenergy Lab, Uttaranchal University; Faculty of Applied Sciences and Biotechnology, Shoolini University; and Department of Biotechnology, Dolphin (P.G.) Institute of Biomedical and Natural Sciences), Korea (Department of Environmental Engineering, The University of Seoul), and Russia (Joint Institute for High Temperatures of the Russian Academy of Sciences and Department of Environmental Monitoring and Forecasting, RUDN University), led by Dr. Pankaj Kumar Chauhan from Shoolini University, India, have developed wastewater treatment technology based on algal bioremediation. Their study is published in Science of the Total Environment.
Algae rapidly cover water bodies with a green film or cause red tides, using the nitrogen, carbon, phosphorous, or heavy metals present in water as nutrition. A high algal load in the water then creates competition for nutrients and sunlight with other microorganisms, causing a reduction in the number of bacteria present in the water. These are some of the properties that make algae promising wastewater purification agents. Added to these, is the fact that they're are eco-friendly, self-sustaining, and cost-effective as a wastewater treatment agent.
Dr. Chauhan explains the basis of the technology developed by his team: "We selected a novel microalgal strain Pseudochlorella pringsheimii because it can tolerate high pollutant load and can grow over a wide range of temperatures. Moreover, under conditions of stress, Pseudochlorella is known to accumulate high amounts of lipids in their cells, opening up the possibility of using this algal biomass for biofuel synthesis.''
For their experiments, the researchers collected the Pseudochlorella pringsheimii microalgae strain from a natural pond and cultivated it in artificial tanks of raw urban wastewater which contained various heavy metal pollutants and antibiotic resistant bacteria. After 14 days of cultivation, they measured three parameters in these tanks: the water quality, and growth and biochemical composition of P. pringsheimii. They also assessed the possibility of using the microalgae-treated water for fish farming.
The findings of this pilot-scale study were extremely encouraging. P. pringsheimii cultivation significantly improved the water quality by removing heavy metals and harmful microorganisms. Dr. Chauhan explains enthusiastically that "after the treatment, we observed that the levels of water pollution indicators such as chemical oxygen demand (COD), alkalinity, and hardness reduced by 83.2%, 66.7%, and 69.6%, respectively. Moreover, the algal growth naturally nearly eliminated the total bacteria and coliform in the water. We also saw a significant increase in the lipid content in wastewater-grown algal biomass in comparison to the algae grown in the control medium. This means, that this algae can be recycled for biofuel synthesis.''.
In addition, while no sucker fish survived in raw wastewater, in treated wastewater, 84% of them not only survived but over ten days, their bodyweight also increased by 47%.
This new technology is, thus, a remarkable success in eco-friendly wastewater treatment research and highlights the suitability of using treated water for low-cost fish cultivation. Dr. Chauhan is hopeful that their microalgae-based bioremediation technique will pave the way for a greener and more sustainable future.

Российская научная экспедиция обнаружила на острове Ева-Лив (архипелаг Земля Франца-Иосифа) крупнейшее в истории арктических исследований лежбище краснокнижных атлантических моржей.

The press service of the Russian Arctic National Park reported that on the 9th of September, a scientific Russian expedition, initiated by the Arctic Scientific Center of Rosneft, had returned to Arkhangelsk from the Arctic. The expedition’s aim was to conduct environmental monitoring of the Red Data Book (a state document recording rare and endangered animal, plant and fungi species) species for the second year in a row on Franz Josef Land and Novaya Zemlya.
Having studied the data collected by camera traps installed in the areas during last year’s expedition, scientists had discovered new food bases and rookeries for walruses to explore during this year’s expedition.
During the expedition, scientists and zoologists from the A.N. Severtsov Institute of Ecology and Evolution, the Lomonosov Moscow State University Marine Research Center, as well the Russian Arctic National Park, examined 34 islands on Franz Josef Land, Novaya Zemlya and Victoria Island. Using unmanned aerial vehicles, a census of the number of walruses at the largest rookeries in the three areas were carried out.
According to preliminary data, more than seven thousand walruses were recorded, which is two times as many as last year. This was also when the largest walrus habitat in the history of Arctic exploration was found on the northernmost island of the Franz Josef Land archipelago, the Eva-Liv island.
Some of the areas covered in both this and last years’ expeditions are Russian Arctic national parks. According to the head of the expedition, Svetlana Artemyeva, "the territory of the national parks is optimal for Atlantic walrus tracking, because at least one large group of the animal lives there. The archipelago itself is quite convenient for exploring rookies too as the distances are small and there is a huge number of haul-outs areas for Walruses to utilize."
This year the expedition’s crew tagged 16 satellite tracking devices onto walruses. The walrus females and calves were prioritized in this year’s tagging process.

Первое научное исследование воды в озере Байкал на предмет загрязнения ее микропластиком, проведенное летом биологами МГУ им. М.В.Ломоносова, показало, что концентрация пластиковых частиц сравнима с некоторыми районами Тихого и Атлантического океанов. Все это отходы жизнедеятельности человека: мусор, очистные сооружения, дешевые полимерные рыбацкие сети, которые в случае повреждения просто бросают в воде.

Malgré son air sauvage, le lac Baïkal n'est pas épargné par la pollution plastique. « La présence humaine coûte cher à la plus grande masse d'eau douce du monde », s'alarme le quotidien russe « Kommersant ». Le journal indépendant rapporte les résultats de la première étude scientifique menée sur la qualité des eaux, qui révèle des concentrations de microparticules plastiques comparables à celles que l'on retrouve dans les vortex de déchets du Pacifique ou de l'Atlantique.
Ses rives sont pourtant relativement peu peuplées, avec 120.000 personnes vivant autour. « Par quoi est donc contaminé le lac ? », s'interroge « Kommersant ».
Prolifération de filets de pêche abandonnés
Aux déchetteries sauvages, aux ordures laissées par les nombreux touristes et aux pollutions issues des activités humaines apportées par ses affluents s'ajoute la prolifération de filets de pêche tapissant les fonds lacustres. Les pêcheurs se les fournissent par importation chinoise et préfèrent abandonner sur place ces filets bon marché mais peu résistants plutôt que les récupérer. En se décomposant, ils rendent des zones entières toxiques pour les espèces locales.
Les scientifiques soulignent aussi l'inefficacité, voire l'absence de systèmes de traitement des eaux usées dans les villes de la région, notamment à Irkoutsk, la grande cité à proximité du lac.
Leur inquiétude est d'autant plus grande que, comme l'explique le journal, « il n'est plus possible d'éliminer toutes ces particules des eaux du Baïkal. Ainsi, au fond du lac, une fine couche de microplastiques se forme progressivement, qui inscrira, dans un futur proche, notre ère de surconsommation dans le profil géologique ».

Исследователи Национального исследовательского университета «Высшая школа экономики» задались вопросом: дает ли инженерно-техническая и естественно-научная специализация (STEM) заметное экономическое преимущество перед гуманитарной и социальной и меняется ли это преимущество в разных возрастных группах? Оказалось, что STEM-специалисты не получают дополнительных выгод ни изначально, ни с возрастом.

HSE University economists question whether Russian STEM specialists are better paid than non-STEM specialists. They compare wages of professionals with STEM and no STEM majors, and those working in STEM and no STEM jobs and explore how the gap evolves over the life cycle. They find that there is no advantage of STEM major and STEM job over their no STEM alternative. They present their findings in a paper published in the Voprosy Ekonomiki journal.
There is a consensual view that STEM (Science, Technology, Engineering and Math) related education and occupations play a key role for productivity growth and ultimately in providing the wealth of nations. Though all developed countries expand STEM education, they often keep complaining that these specialists are still in short supply. As a reflection of this situation, there is a loudly voiced criticism that the composition of university graduates does not fit the actual demand, and in suggestions to increase the number of students in STEM majors and decrease in social sciences and humanities. The perceived shortage should positively affect wages for STEM workers compared to specialists with the same level of education but alternative majors. This story is well known in many countries. Is Russia among them?
STEM education differs from that in humanities and social sciences, as it is usually more specialized and provides more practical skills than that in 'soft sciences'. On the one hand, this helps graduates to start working earlier, but on the other hand, their skills face much higher risk of becoming obsolete since the technological frontier is moving very fast. A recent study in the US has found that STEM professionals start their careers with higher wages but the difference evaporates as they get older. Professionals without STEM diplomas have lower wages in the beginning but they benefit from a longer period of wage growth as they are less affected by the technological race. In the end, STEM wage advantage appears to be questionable.
The scholars from HSE University explore the issue exploiting all available data sources. These are aggregate data from the official statistics, micro-data from a few large-scale Rosstat administered household and enterprise surveys, and the HSE Russian Longitudinal Monitoring Survey. One of limitations of all these data sources is that they do not have information on data on individual abilities, and this does not allow to account for selection in STEM occupations.
On the supply side, they document very large annual outflow of graduates with STEM degrees from the educational system. Over the last two decades, on average about 300,000 people with STEM degrees, or between 28% and 40% of the total number of university graduates, annually enter the labor market.
On the demand side, the fraction of STEM professionals among all professionals remains at about one quarter. It decreases over age, making about 40% in 25-29 years old, about 30% among those of 40-44 and about 20% at the age of 60. Some professionals move to managerial positions, while others leave STEM for other fields. The study suggests that even after accounting for all explanations (such as the fact that not all graduates work in the field), STEM supply is likely to exceed STEM demand.
The authors in their analysis exploit different data sets and different econometric specifications for checking the robustness of the results. The main finding that a STEM degree and/or a STEM job do not offer any wage advantages compared to non-STEM options remains robust. Furthermore, as individuals get older, they are likely to earn even less than non-STEM majors, all other things being equal. Generally, in STEM jobs, newly acquired skills are valued higher than long time experience: skills get older and obsolete too fast. Those who are willing to stay in the profession for a long time have to retrain continuously and run faster than recent graduates.
The data suggest that tech and science jobs in Russia remain male-dominated: women make up only one fourth of those with a STEM degree and in professional STEM jobs. Women in STEM earn also less than men - particularly at older ages - and their earnings decrease relatively faster. One of the tentative explanations can refer to the fact that public sector institutions are female dominated and pay more in line with experience. The study rejects the assumption that there is a shortage of STEM professionals and shows that appeals to increase the number of students in STEM fields do not get the empirical support.
If there is a shortage in the market, this is a shortage of STEM skills, not a shortage of STEM graduates.

Российско-итальянская исследовательская группа Университета ИТМО и Римского университета Тор Вергата разработала пасту из наночастиц кремния и диоксида титана, усиливающую поглощение света в перовскитных солнечных элементах, повышая их эффективность на 21.1%.

Researchers from the ITMO University, in Russia, and the University of Rome Tor Vergata, in Italy, have developed a paste made of titanium dioxide (TiO2) and resonant silicon nanoparticles which they claim can improve light absorption in perovskite solar cells based on methylammonium lead iodide (MAPbI3).
The scientists created a mesoporous electron transport layer based on optically resonant silicon nanoparticles which were then incorporated into TiO2 paste. "Such particles serve as nanoantennae - they catch light and it resonates inside them. And the longer light stays in the photoactive layer, the more of it is absorbed by the material," said Sergey Makarov, professor at ITMO’s school of physics and engineering.
The silicon nanoparticles are Mie-resonant, which means they are able to create magnetic or electric resonance based on displacement currents. "Thanks to this effect, the nanoparticles can amplify various optical phenomena, including light absorption and spontaneous radiation. In other words, they do work as nanoantennae," the researchers stated, noting that including them in the cell improves light absorption without reduction of the active material.
Before using the nanoparticles, the researchers considered the electrophysical and optical properties of all layers and the nanoparticles themselves, especially when they are exposed to external radiation and voltage. They then decided not to apply them to the upper transport layer, which would have prevented the light reaching the nanoparticles, as it would have been absorbed by all the layers below, and placed them, via spin-coating, in the next layer after the perovskite, which brought them closer to the light source.
The Russian-Italian group said the paste can be used with any perovskite cell composition and architecture and that it increases manufacturing cost by only 0.3%. "The paste can be easily applied with other methods, not only with spin coating. It’s a raw universal product that can be used in other types of solar cells, as well as in the production of various devices - photodetectors, harvesters, and optoelectronics," it further explained. "Such production is also environmentally-friendly, as we don’t use any rare materials."
The developed cell achieved a power conversion efficiency of 21.1%.
The process to produce the paste is presented in the paper Mie-resonant mesoporous electron transport layer for highly efficient perovskite solar cells, published in Nano Energy.

Международная исследовательская группа во главе со Сколтехом и IBM создала энергоэффективный оптический переключатель, способный заменить электронные транзисторы в новом поколении компьютеров. Для его переключения достаточно нескольких фотонов, он не требует охлаждения и работает до 1000 раз быстрее, чем современные транзисторы.

An international research team led by Skoltech and IBM has created an extremely energy-efficient optical switch that could replace electronic transistors in a new generation of computers manipulating photons rather than electrons. In addition to direct power saving, the switch requires no cooling and is really fast: At 1 trillion operations per second, it is between 100 and 1,000 times faster than today’s top-notch commercial transistors. The study comes out Wednesday in Nature.
"What makes the new device so energy-efficient is that it only takes a few photons to switch," the first author of the study, Dr. Anton Zasedatelev commented. "In fact, in our Skoltech labs we achieved switching with just one photon at room temperature! That said, there is a long way to go before such proof-of-principle demonstration is utilized in an all-optical co-processor," added Professor Pavlos Lagoudakis, who heads the Hybrid Photonics Labs at Skoltech.
Since a photon is the smallest particle of light that exists in nature, there is really not much room for improvement beyond that as far as power consumption goes. Most modern electrical transistors take tens of times more energy to switch, and the ones that use single electrons to achieve comparable efficiencies are way slower.
Besides performance issues the competing power-saving electronic transistors also tend to require bulky cooling equipment, which in turn consumes power and factors into the operating costs. The new switch conveniently works at room temperature and therefore circumvents all these problems.
In addition to its primary transistor-like function, the switch could act as a component that links devices by shuttling data between them in the form of optical signals. It can also serve as an amplifier, boosting the intensity of an incoming laser beam by a factor of up to 23,000.
How it works
The device relies on two lasers to set its state to "0" or "1" and to switch between them. A very weak control laser beam is used to turn another, brighter laser beam on or off. It only takes a few photons in the control beam, hence the device’s high efficiency.
The switching occurs inside a microcavity - a 35-nanometer thin organic semiconducting polymer sandwiched between highly reflective inorganic structures. The microcavity is built in such a way as to keep incoming light trapped inside for as long as possible to favor its coupling with the cavity’s material.
This light-matter coupling forms the basis of the new device. When photons couple strongly to bound electron-hole pairs - aka excitons - in the cavity’s material, this gives rise to short-lived entities called exciton-polaritons, which are a kind of quasiparticles at the heart of the switch’s operation.
When the pump laser - the brighter one of the two - shines on the switch, this creates thousands of identical quasiparticles in the same location, forming so-called bose-einstein condensate, which encodes the "0" and "1" logic states of the device.
To switch between the two levels of the device, the team used a control laser pulse seeding the condensate shortly before the arrival of the pump laser pulse. As a result, it stimulates energy conversion from the pump laser, boosting the amount of quasiparticles at the condensate. The high amount of particles in there corresponds to the "1" state of the device.
The researchers used several tweaks to ensure low power consumption: first, efficient switching was aided by the vibrations of the semiconducting polymer’s molecules. The trick was to match the energy gap between the pumped states and the condensate state to the energy of one particular molecular vibration in the polymer. Second, the team managed to find the optimal wavelength to tune their laser to and implemented a new measurement scheme enabling single-shot condensate detection. Third, the control laser seeding the condensate and its detection scheme were matched in a way that suppressed the noise from the device’s "background" emission. These measures maximized the signal-to-noise level of the device and prevented an excess of energy from being absorbed by the microcavity, which would only serve to heat it up through molecular vibrations.
"There’s still some work ahead of us to lower the overall power consumption of our device, which is currently dominated by the pump laser that keeps the switch on. A route toward that goal could be perovskite supercrystal materials like those we’re exploring with collaborators. They have proven excellent candidates given their strong light-matter coupling which in turn leads to a powerful collective quantum response in the form of superfluorescence," the team comments.
In the larger scheme of things, the researchers see their new switch as but one in the growing toolkit of all-optical components they have been assembling over the past few years. Among other things, it includes a low-loss silicon waveguide for shuttling the optical signals back and forth between transistors. The development of these components takes us ever closer to optical computers that would manipulate photons instead of electrons, resulting in vastly superior performance and lower power consumption. The research at Skoltech was supported by the Russian Science Foundation (RSF).

Математики Сколтеха обнаружили у квантового процессора компании Google ряд ограничений, снижающих производительность компьютера при достижении высокой плотности переменных.

CPQM’s Laboratory for Quantum Information Processing has collaborated with the CDISE supercomputing team "Zhores" to emulate Google’s quantum processor. Reproducing noiseless data following the same statistics as Google’s recent experiments, the team was able to point to a subtle effect lurking in Google’s data. This effect, called a reachability deficit, was discovered by the Skoltech team in its past work. The numerics confirmed that Google’s data was on the edge of a so-called, density-dependent avalanche, which implies that future experiments will require significantly more quantum resources to perform quantum approximate optimization. The results are published in the field’s leading journal Quantum.
From the early days of numerical computing, quantum systems have appeared exceedingly difficult to emulate, though the precise reasons for this remain a subject of active research. Still, this apparently inherent difficulty of a classical computer to emulate a quantum system prompted several researchers to flip the narrative.
Scientists such as Richard Feynman and Yuri Manin speculated in the early 1980s that the unknown ingredients which seem to make quantum computers hard to emulate using a classical computer could themselves be used as a computational resource. For example, a quantum processor should be good at simulating quantum systems, since they are governed by the same underlying principles.
Such early ideas eventually led to Google and other tech giants creating prototype versions of the long-anticipated quantum processors. These modern devices are error-prone, they can only execute the simplest of quantum programs and each calculation must be repeated multiple times to average out the errors in order to eventually form an approximation.
Among the most studied applications of these contemporary quantum processors is the quantum approximate optimization algorithm, or QAOA (pronounced "kyoo-ay-oh-AY"). In a series of dramatic experiments, Google used its processor to probe QAOA’s performance using 23 qubits and three tunable program steps.
In a nutshell, QAOA is an approach wherein one aims to approximately solve optimization problems on a hybrid setup consisting of a classical computer and a quantum co-processor. Prototypical quantum processors such as Google’s Sycamore are currently restricticted to performing noisy and limited operations. Using a hybrid setup, the hope is to alleviate some of these systematic limitations and still recover quantum behavior to take advantage of, making approaches such as QAOA particularly attractive.
Skoltech scientists have made a series of recent discoveries related to QAOA, for example see the write-up here. Prominent among them being an effect that fundamentally limits the applicability of QAOA. They show that the density of an optimization problem - that is, the ratio between its constraints and variables - acts as a major barrier to achieving approximate solutions. Additional resources, in terms of operations run on the quantum co-processor, are required to overcome this performance limitation. These discoveries were done using pen and paper and very small emulations. They wanted to see if the effect they recently discovered manifested itself in Google’s recent experimental study.
Skoltech’s quantum algorithms lab then approached the CDISE supercomputing team led by Oleg Panarin for the significant computing resources required to emulate Google’s quantum chip. Quantum laboratory member, Senior Research Scientist Dr. Igor Zacharov worked with several others to transform the existing emulation software into a form that permits parallel computation on Zhores. After several months, the team managed to create an emulation that outputs data with the same statistical distributions as Google and showed a range of instance densities at which QAOA performance sharply degrades. They further revealed Google’s data to lie at the edge of this range beyond which the current state of the art would not suffice to produce any advantage.
The Skoltech team originally found that reachability deficits - a performance limitation induced by a problem’s constraint-to-variable ratio - were present for a kind of problem called maximum constraint satisfiability. Google, however, considered the minimization of graph energy functions. Since these problems are in the same complexity class, it gave the team conceptual hope that the problems, and later the effect, could be related. This intuition turned out to be correct. The data was generated and the findings clearly showed that reachability deficits create a type of an avalanche effect, placing Google’s data on the edge of this rapid transition beyond which longer, more powerful QAOA circuits become a necessity.
Oleg Panarin, a manager of data and information services at Skoltech, commented: "We are very pleased to see our computer pushed to this extreme. The project was long and challenging and we’ve worked hand in glove with the quantum lab to develop this framework. We believe this project sets a baseline for future demonstrations of this type using Zhores."
Igor Zacharov, a senior research scientist at Skoltech, added: "We took existing code from Akshay Vishwanatahan, the first author of this study, and turned it into a program that ran in parallel. It was certainly an exciting moment for all of us when the data finally appeared, and we had the same statistics as Google. In this project, we created a software package that can now emulate various state-of-the-art quantum processors, with as many as 36 qubits and a dozen layers deep."
Akshay Vishwanatahan, a PhD student at Skoltech, concluded: "Going past a few qubits and layers in QAOA was a significantly challenging task at the time. The in-house emulation software we developed could only address toy-model cases and I initially felt that this project, while an exciting challenge, would prove nearly impossible. Fortunately, I was amidst a group of optimistic and high-spirited peers and this further motivated me to follow through and reproduce Google’s noiseless data. It was certainly a moment of great excitement when our data matched Google’s, with a similar statistical distribution, from which we were finally able to see the effect’s presence."

На территории Республики Тыва обнаружен геоглиф быка возрастом около 4000 лет и высотой 3 метра, выложенный галькой и песчаником. Это первая подобная находка в Центральной Азии.

Archaeologists conducting excavations at the Jonderguéi 22 site in the south-west of the Republic of Tuva in southern Siberia have made the exciting discovery of a bull geoglyph. It is believed to be the first animal geoglyph find in the entire Central Asia region. The excavations near Khondergey village, close to Russia’s border with Mongolia, were conducted by a team of archaeologists from the Institute of History of Material Culture of the Russian Academy of Sciences (IIMK RAS) and LLC Krasnoyarsk Geoarchaeology.
The 3-by-4-meter (10-by-13-foot) bull geoglyph was found in a large Early Bronze Age burial site. Ceramics dating as far back as 4000 years ago have also been unearthed at the site, which means the Siberian bull geoglyph is twice as old as the Nazca Lines in Peru and predates the UK’s Uffington Horse geoglyph by a thousand years.
From Peru’s Nazca Lines to the Siberian Bull Geoglyph
Geoglyphs are large motifs, usually larger than 4 metres (13 feet), created on the ground by an arrangement of pebbles, stones, gravel and other durable materials. They can be either positive, that is made by an arrangement of the materials on the ground, or negative, that is made by carving out part of the ground. They differ from petroglyphs in that the latter are rock art made by carving or chipping out designs on rock surfaces. Geoglyphs are much larger designs created in such a way that they stand out from the surface of the earth.
The most famous geoglyphs are perhaps the Nazca Lines of Peru which, according to Encyclopaedia Britannica, are "groups of geoglyphs, large line drawings that appear, from a distance, to be etched into the Earth’s surface on the arid Pampa Colorada…, northwest of the city of Nazca in southern Peru. They extend over an area of nearly 190 square miles (500 square km)." While most of the Nazca Lines are around 2000 years old, some date back to an even earlier "mystery" culture.
The United Kingdom’s famous Uffington Horse or Uffington White Horse is a relic from the Iron Age carved into the white chalk hillside of the Berkshire Downs. It is one of a series of human and equine geoglyph figures cut into the chalk hills of southern England.
Earlier this year, a group of eight geoglyphs that are believed to be the largest in the world were found in the Thar Desert in India. These incredible geoglyphs are so big that their creators likely never saw the entirety of their work.
The geoglyph of the bull found in Siberia recently stands out not for its size but for its age (2000 BC) and its location. No other animal geoglyph has been found in Central Asia so far except this one!
What’s So Special about the Siberian Bull Geoglyph?
Marina Kilunovskaya, who leads the Tuvan archaeological expedition, told The Siberian Times, "The bull motif is very typical for the Central Asia cultures of the Early Bronze Era. Later in Scythian times bulls were replaced by deer. We do see bulls as petroglyphs around Tuva and the neighbouring territories - but coming across the animal geoglyph is a unique discovery for the whole region of Central Asia. We didn’t previously find such stone compositions."
The geoglyph is constructed of pebbles and pieces of local sandstone arranged together to resemble a bull. However, in the 1940s road construction work unfortunately completely destroyed its head and torso and only its hindquarters and tail remain. According to Market Research Telecast, Natalia Lazarevskaya, a member of the Tuva excavation team said that only the haunches of the find remain preserved while the rest was dismantled by road work.
Members of the archaeology team hope that the uniqueness of the find coupled with the damage it has suffered in modern times will induce authorities to ensure its preservation as part of a protected site. Heritage Daily has quoted Marina Kilunovskaya as saying, "Although we can recognise the bull depiction, allowing us to reconstruct the lost parts with a high degree of probability, we have never seen stone layouts such as these before. In our opinion, the uniqueness of the find and the threat to the site due to the adjacent road requires further preservation."
Hopefully, further examination of the fascinating Siberian bull geoglyph and the area where it was discovered will throw more light on its origins including who made it and why.

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