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Perennially frozen ground and sea ice are key constituents of permafrost coastal systems, and their presence is the primary difference between temperate and high-latitude coastal processes. These systems are some of the most rapidly changing landscapes on Earth and, in the Arctic, are representative of the challenges being faced at the intersection between natural and anthropogenic systems. Permafrost thaw, in combination with increasing sea level and decreasing sea-ice cover, exposes arctic coastal and nearshore areas to rapid environmental and social changes. Based on decadal timescales, observations in the Arctic indicate an increase in permafrost coastal bluff erosion and storm surge flooding of low-lying ice-rich permafrost terrain. However, circum-arctic observations remain limited and the factors responsible for the apparent increase in arctic coastal dynamics are poorly constrained. A better understanding of permafrost coastal systems and how they are responding to changes in the Arctic is important since a high proportion of Arctic residents live on or near coastlines, and many derive their livelihood from terrestrial and nearshore marine resources. An expanding industrial, scientific, and commercial presence in the Arctic Ocean will also require advanced knowledge about permafrost coastlines as terrestrial access points. Since the issues involved span political, cultural, geographical, and disciplinary borders, an international network focused on permafrost coastal systems in transition is needed. An integrative network focused on permafrost coastal systems is required to realize and address the scale and complexity of the processes, dynamics, and responses of this system to physical, ecological, and social change. A primary focus of such an effort would be guided by the fact that the issues and impacts associated with permafrost coastal systems in transition are far greater than any single institution or discipline is capable of addressing alone. Future permafrost coastal system dynamics will challenge conventional wisdom as the system enters a new state impacting human decision making and adaptation planning, cultural heritage resources and ecosystems, and likely resulting in unforeseen challenges across the Arctic.

Larvae of African chironomid Polypedilum vanderplanki represent highly developed mechanism of anhydrobiotic conservation of metabolism which allowing them to stay alive for many years in the absence of water and be utilized as a model organisms in long-term projects, including the spaceflight. In this paper we shortly overview the main properties of anhydrobiosis of the larvae and describe the main space experiments where the insect was used as a model organism for investigation of influence of spaceflight environment of latent stages of invertebrates., 資料番号: AA0063706087

Broad, long-living, ice-free areas in mid-winter northeast of Svalbard between 2011 and 2014 are investigated. The formation of these persistent and re-emerging anomalies is linked, hypothetically, with the increased seasonality of Arctic sea ice cover, enabling an enhanced influence of oceanic heat on sea ice, and in particular, heat transported by Atlantic Water. The ‘memory’ of ice-depleted conditions in summer is transferred to the fall season, through excess heat content in the upper mixed layer, which in turn transfers to mid-winter via thinner and younger ice. This thinner ice is more fragile and mobile, thus facilitating the formation of polynyas and leads. When openings in ice cover form along the Atlantic Water pathway, weak density stratification at the mixed layer base supports the development of thermohaline convection, which further entrains warm and salty water from deeper layers. Convection-induced upward heat flux from the Atlantic layer retards ice formation, either keeping ice thickness low or blocking ice formation entirely. Certain stages of this chain of events have been examined in a region north of Svalbard and Franz Joseph Land, between 80-83°N and 15-60°E, where the top hundred meters of Atlantic inflow through the Fram Strait cools and freshens rapidly. Complementary research methods, including statistical analyses of observations and numerical modelling, are used to support our basic concept that the recently observed retreat of sea ice northeast of Svalbard in winter may be explained by a positive feedback between summer ice decay and the growing influence of oceanic heat on a seasonal time scale.

Виконано комплекснi дослiдження природної i наведеної (рент-генiвським i гамма-випромiнюванням) термолюмiнесценцiї, трекiв VH-ядер i космогенних радiонуклiдiв iзрiзними перiодами напiврозпаду в хондритi Куня–Ургенч Н5. Експериментальнi данi, результати кореляцiйного аналiзу i теоретичного моделювання використанi для реконструкцiї ударної-термiчної i радiацiйної iсторiї цього хондрита, оцiнки його доатмосферних розмiрiв i протяжностi орбiти, а також для характеристики радiацiйних умов у гелiосферi на спадi 22-го сонячного циклу. Выполнены комплексные исследования естественной инаведенной (рентгеновским и гамма-излучением) термолюминесценции, треков VH-ядер и космогенных радионуклидов с разными периодами полураспада в свежевыпавшем хондрите Куня–Ургенч Н5. Экспери-ментальные данные, результаты корреляционного анализа и теоретического моделирования использованыдля реконструкции ударно-термической и радиационной истории этого хондрита, оценки его доатмосферных размеров и протяженности орбиты, а также для характеристики радиационных условий в гелиосфере на спаде 22-го солнечного цикла. The fresh-fallen Kunya–Urgench H5 chondrite was studied in various aspects including natural and induced (X-rayand γ-ray) thermoluminescence, tracks of VH nuclei, and cosmogenic radionuclides with different half-lives. Theexperimental data, comparative analysis, and theoretical modelling were used to reconstruct the shock-thermal andradiation history of the chondrite, to estimate its preatmospheric size and orbit dimensions, and to characterizethe radiation conditions in the heliosphere during the decline of the 22nd solar cycle.

This article deals with the problem of ecological danger of road infrastructure objects. Road infrastructure includes bus stations, bus depots, car service centers and roadside cafes located throughout the highway system. With the implementation of mass-produced counterfeit water and food in the catering outlets and around the purification of them from all kinds of infections is relevant.

Portfolio risk is a function of the number of stocks held in portfolios. We simulate portfolios using daily observations for all traded and delisted equities in Canada from 1975 to 2011 and we calculate several measures of risk, including heavy-tailed to account for black swan events. For each risk measure, we calculate the average number of portfolio holdings and the upper limits of these holdings to assure investors of a specific reduction in diversifiable risk. In contrast to previous literature that suggests 10-15 stocks are enough to provide adequate diversification for an average investor, we find that in fact more than 50 stocks are needed to achieve the same level of diversification most of the time instead of on average.

Given a normal complete variety $Y$, distinct effective Weil divisors $D_1,... D_n$ of $Y$ and positive integers $d_1,... d_n$, we spell out the conditions for the existence of an abelian cover of $Y$ branched with order $d_i$ on $D_i$. As an application, we prove that a Galois cover of a normal complete toric variety branched on the torus-invariant divisors is itself a toric variety., Dedicated to Alberto Conte on his 70th birthday. Version 2: the assumptions in the application (Thm. 3.7) have been weakened; minor modifications of the exposition

Основа развития (оценка жизненного цикла). В этом исследовании были сравнены экологические показатели различных вариантов обращения с отходами. И затраты изменение энергии, отказавшись от выброса вредных газов в атмосферу.Development of an LCA (Live Cycle Assessment) In this study the environmental performance of different waste management options have been compared. And Waste change to energy, avoiding harmful gases in atmosphere.

Вимiряно змiст космогенних iзотопiв, зокрема, 60Co i 26Al,i щiльнiсть трекiв VH-ядер в LL6-хондритi Kilabo. Отриманi результати, а також наявнi данi [5] за змiстом26Al i благородних газiв в якому щойно випав LL6-хондрит Bensour були використанi для визначення ранiше розвиненими методами до атмосферних розмiрiв i орбiт цих хондритiв. Близькiсть орбiт хондритiв Kilabo i Bensour, наявна схожiсть їх складiв, структури i петрографiї дозволяють припускати їх походження з одногоджерела, а схожiсть спектрiв вiддзеркалення LL6-хондритiв i астероїда головного поясу 3628 Boznemcova дозволяють розглядати цей астероїд як батькiвське тiло LL6-хондритiв. По сукупностi отриманої iнформацiї пропонується наступний сценарiй: (1) вибивання обидва хондритiв з астероїда 3628 Boznemcova 19 млн. рокiв назад (приблизно на 2.2 а.о. вiд Сонця), причому хондрит Bensour був вибитий з глибоких шарiв астероїда,якi були повнiстю екранованi вiд космiчних променiв, а речовина хондрита Kilabo, ймовiрно, опромiнювалася космiчними променями на поверхнi астероїда протягом 14 млн. рокiв до вибивання; (2) дрейф хондритiв пiд дiєю ефекту Ярковського в область вiкового резонансу g=g6 iз змiною великiй пiвосi a на 0.05 а.о. за 18 млн.рокiв i (3) резонансний переклад хондритiв Kilabo i Bensour на сучаснi орбiти за останнiй 1 млн. рокiв. Измерены содержания космогенных изотопов, в частности, 60Co и 26Al, и плотность треков VH-ядер в свежевыпавшем LL6-хондрите Kilabo. Полученные результаты,а также имеющиеся данные [5] по содержанию 26Al и благородных газов в свежевыпавшем LL6-хондритеBensour были использованы для определения ранее развитыми методами до атмосферных размеров и орбитэтих хондритов. Близость орбит хондритов Kilabo и Bensour, имеющееся сходство их составов, структуры и петрографии позволяют предполагать их происхождение из одного источника, а сходство спектров отражения LL6-хондритов и астероида главного пояса 3628 Boznemcova позволяют рассматривать этот астероид вкачестве родительского тела LL6-хондритов. По совокупности полученной информации предлагается следую-щий сценарий: (1) выбивание обоих хондритов из астероида 3628 Boznemcova 19 млн. лет назад (примерно на2.2 а.е. от Солнца), причем хондрит Bensour был выбит из глубоких слоев астероида, которые были полностью экранированы от космических лучей, а вещество хондрита Kilabo, вероятно, облучалось космическими лучами на поверхности астероида в течение 14 млн. лет до выбивания; (2) дрейф хондритов под действием эффекта Ярковского в область векового резонанса g = g6 с изменением большой полуоси a на 0.05 а.е. за18 млн. лет и (3) резонансный перевод хондритов Kilabo и Bensour на современные орбиты за последний1 млн. лет. The content of cosmogenic radionuclides, in particular, 60Co and 26Al, as well as VH-nucleus track density in thefresh-fallen Kilabo LL6-chondrite are measured. The obtained results and the available data of [5] on the contentof 26Al and noble gases in the fresh-fallen Bensour LL6-chondrite are used with earlier developed methods fordetermination of the pre-atmospheric sizes and orbits of these chondrites. The closeness of orbits of the Kilabo andBensour chondrites, the striking likeness of their composition, structure and petrography allow us to suppose theirorigin from a single source; at the same time the resemblance of the reflection spectra of the LL6-chondrites with thatof the main belt 3628 Boznemcova asteroid allow us to consider it as the parent body of the LL6-chondrites. On thestrength of all the evidence, the following scenario is suggested: (1) knocking out of both the chondrites from the 3628Boznemcova asteroid at a distance 2.2 AU from the Sun about 19 million years ago, the Bensour chondrite beingknocked out from deeper layers of the parent asteroid, which were completely shielded from cosmic rays, while thematerial of the Kilabo chondrite being probably irradiated by cosmic rays on the asteroid surface for 14 million yearsbefore its knock-out; (2) the drift of the chondrites due to the Yarkovsky effect into the region of secular resonanceg =g6, which was accompanied by variation of the semimajor axis a by 0.05 AU over 18 million years; (3) theresonance transfer of the Kilabo and Bensour chondrites to their present orbits over the last 1 million years.

This immersion experience exposed students from multiple disciplines and several nations to basic and advanced Antarctic research techniques necessary for understanding the area of the world most affected by climate change.This course offered a general overview of several fields, techniques and technologies used to collect and analyze data, hands-on training in multiple disciplines and incorporate research projects that use a systems approach and were enhanced by international perspectives on newly synthesized science hypotheses. The field school provided the opportunity and forum for collaborations between a number of scientists and young researchers from a variety of backgrounds. The students gained knowledge of one of the most rapidly warming region on Earth and sociological impacts. They also acquired hands-on field techniques for collecting data, data sharing and management. They learned logistical requirements for research at several international Antarctic stations and developed international and interdisciplinary research projects and collaborators. In addition, they will participate in disseminating this information and knowledge to other young researchers around the world. The abstract has been submitted while the summer school has been conducted in Antarctica.

Problem formulation and complishing resource-intensive calculations through realization of distributed network of mixed computer systems in Automobile and Highway University for calculating experiments with mechatronic systems has been considered

An experiment on the radiative pi^+ meson photoproduction from the proton (gamma p->gamma pi^+ n) was carried out at the Mainz Microtron MAMI in the kinematic region 537 MeV, Comment: 34 pages, 12 figures, final version to appear in Eur. Phys. J. A; typos have been corrected

An experiment on the radiative pi^+ meson photoproduction from the proton (gamma p->gamma pi^+ n) was carried out at the Mainz Microtron MAMI in the kinematic region 537 MeV, 34 pages, 12 figures, final version to appear in Eur. Phys. J. A; typos have been corrected

Let $(C,\iota)$ be a stable curve with an involution. Following a classical construction one can define its Prym variety $P$, which in this case turns out to be a semiabelian group variety and usually not complete. In this paper we study the question whether there are ``good'' compactifications of $P$ in analogy to compactified Jacobians. The answer to this question depends on whether we consider degenerations of principally polarized Prym varieties or degenerations with the induced (non-principal) polarization. We describe degeneration data of such degenerations. The main application of our theory lies in the case of degenerations of principally polarized Prym varieties where we ask whether such a degeneration depends on a given one-parameter family containing $(C,\iota)$ or not. This allows us to determine the indeterminacy locus of the Prym map., Comment: Final version, to appear in Crelle Journal. 51 pages, 15 *.eps pictures

Contains fulltext : 240328.pdf (Author’s version preprint ) (Open Access) In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in sample estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty: non-standard errors. To study them, we let 164 teams test six hypotheses on the same sample. We find that non-standard errors are sizeable, on par with standard errors. Their size (i) co-varies only weakly with team merits, reproducibility, or peer rating, (ii) declines significantly after peer-feedback, and (iii) is underestimated by participants. 31 mei 2023

Perennially frozen ground and sea ice are key constituents of permafrost coastal systems, and their presence is the primary difference between temperate and high-latitude coastal processes. These systems are some of the most rapidly changing landscapes on Earth and, in the Arctic, are representative of the challenges being faced at the intersection between natural and anthropogenic systems. Permafrost thaw, in combination with increasing sea level and decreasing sea-ice cover, exposes arctic coastal and nearshore areas to rapid environmental and social changes. Based on decadal timescales, observations in the Arctic indicate an increase in permafrost coastal bluff erosion and storm surge flooding of low-lying ice-rich permafrost terrain. However, circum-arctic observations remain limited and the factors responsible for the apparent increase in arctic coastal dynamics are poorly constrained. A better understanding of permafrost coastal systems and how they are responding to changes in the Arctic is important since a high proportion of Arctic residents live on or near coastlines, and many derive their livelihood from terrestrial and nearshore marine resources. An expanding industrial, scientific, and commercial presence in the Arctic Ocean will also require advanced knowledge about permafrost coastlines as terrestrial access points. Since the issues involved span political, cultural, geographical, and disciplinary borders, an international network focused on permafrost coastal systems in transition is needed. An integrative network focused on permafrost coastal systems is required to realize and address the scale and complexity of the processes, dynamics, and responses of this system to physical, ecological, and social change. A primary focus of such an effort would be guided by the fact that the issues and impacts associated with permafrost coastal systems in transition are far greater than any single institution or discipline is capable of addressing alone. Future permafrost coastal system dynamics will challenge conventional wisdom as the system enters a new state impacting human decision making and adaptation planning, cultural heritage resources and ecosystems, and likely resulting in unforeseen challenges across the Arctic.