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In terms of cataloged debris produced, the anti-satellite test carried out by Russia, in November 2021, at an altitude of about 480 km, leading to the destruction of the old satellite Cosmos 1408, was the second worst to date and represented the third worst fragmentation in orbit. It generated more than 1/4 of the cataloged debris produced over 55 years by all such tests and almost twice as many as were produced by all previous Soviet tests. After placing this event in its historical context, this paper analyzes in detail how the evolution of the Cosmos 1408 debris cloud affected the environment below 600 km in the first seven months, focusing on the two operational space stations and the Starlink large constellation of satellites. During the first six months following the test, the Cosmos 1408 cloud of fragments nearly doubled the average flux of cataloged objects on the International Space Station and increased by about 3/4 that on China's Tiangong. In the same period, the Starlink large constellation saw an average increase in the flux of cataloged objects of about 20%. Some orbital planes, the "counter-rotating" ones with respect to the Cosmos 1408 debris cloud, were more affected than others, and the affected planes gradually changed over time, due to the differential precession of cloud and constellation nodes. However, being the Starlink constellation 70 km higher up, the flux of Cosmos 1408 cataloged debris steadily decreased over the period analyzed, due to the cloud orbital decay, reducing to just over a quarter of its extrapolated initial value after seven months. • A review of ASAT tests as a source of orbital debris was presented. • The impact of the Cosmos 1408 destruction was put into context. • The cataloged debris flux increase on space stations was computed and discussed. • The debris flux increase and evolution on Starlink orbit planes was analyzed. • A moratorium on this type of ASAT tests was recommended, including low LEO. [ABSTRACT FROM AUTHOR]

Thawing permafrost has affected the structural integrity of buried warm pipelines in cold regions and poses an ongoing threat in the context of climate change. Therefore, characterizing variation in the engineering properties of pipeline foundation permafrost and its effect on the mechanical behavior of pipeline is important. In this paper, the ground temperature distributions around a buried warm pipeline and mechanical response of the pipeline to differential thaw settlement of foundation permafrost are investigated using thermal–mechanical sequential coupling simulation, based on the observational data collected from a selected monitoring site along the China-Russia crude oil pipelines in northeastern China. The results indicate that the thaw-induced settlement of pipeline foundation permafrost develops quickly with the formation and expansion of the thaw bulb in the first 10 years, and then increases slowly when the thaw bulb extends to the weathered granite. Differential thaw settlement will cause a significant change in the deformation and stress of the pipeline near the interface of strong and weak thaw settlement zones. When the length ratio of strong and weak thaw settlement zones is 1, the maximum stress of the pipeline with a thickness of 16 mm is approximately 45% of the allowable stress of X65 steel, and the pipeline remains safe for 30 years. However, the potential failure of the pipeline should be considered due to the continued ground thawing and warming and pipe material aging. Forthcoming research on this topic is needed to evaluate more carefully the structural integrity of buried pipelines in cold regions. [ABSTRACT FROM AUTHOR]

China and Russia have different interests in the Arctic but are forced to look for possible ways of cooperation in energy projects in the current external conditions. This changes the priorities of both countries and, accordingly, transforms the risks. Objectives of the research: to build an algorithm for identifying anthropogenic environmental risks in the context of two major players economic activities in the Arctic region: the Russian Federation and China. In the paper, we formulated an algorithm of environmental risk identification. We identified environmental hazards from the main parameter—the type of economic activity for the extraction of energy resources, premises, and factors for the occurrence of environmental hazards and compiled criteria for risk selection. Methods used: complex analysis (mixed method research): empirical and comparative methods, methods of expert assessments, the method of inductive statistics (inferential statistics) to compare the perception of risk at the level of different groups. Results: the algorithm has been formed for determining risks in the changed external conditions. Major anthropogenic environmental risks are identified from the perspective of the main players in the Arctic—Russia and China, which can help to make the necessary decisions on time and partially prevent environmental degradation. This makes it possible to identify the risks associated with conducting economic activities for the extraction of energy resources in the Arctic region. Therefore, this study contributes to a more accurate identification of anthropogenic environmental risks in the Arctic region. [ABSTRACT FROM AUTHOR]

Ostensibly, Joe Biden's victory over Donald Trump in the 2020 presidential elections should have placed United States international policy back on a familiar path. However, despite the prevalence of a highly traditional vision of US foreign policy, the Biden administration has maintained significant continuities with the previous administration, as reflected in the policy towards China and the withdrawal from Afghanistan. In part, this is due to the constraints produced by the deep divisions that exist at domestic level. This paper aims to unravel the fundamental elements of Biden's foreign policy, focusing on possible ideological and doctrinal elements, strategic priorities, and any continuities and changes relative to his predecessor. [ABSTRACT FROM AUTHOR]

The Joint Statement by the Foreign Ministers of China and Russia on Certain Aspects of Global Governance in Modern Conditions of 23 March 2021 calls for "the establishment of a fairer, more democratic and rational multipolar world order." The paper inquires how constitutional theories of international organisations have in the past and present sought to contribute to world order. It identifies three waves of such theory since the 1960s. Looking in more detail at the ongoing third wave, it identifies and seeks to pull out further a constitutional model which upscales the proto-democratic practices in international organisations by strengthening forums for participation and contestation, which rectifies to the north-south imbalance inter alia rooted in the colonial heritage by involving more actors from the global south, and which tackles the global social question upfront. [ABSTRACT FROM AUTHOR]

Meeting energy needs and ensuring ecological sustainability are important tasks for policymakers. In particular, changing the energy mix used in daily electricity generation can have a major effect on ecological conditions, and this is a previously neglected research topic. Therefore, this paper aims to investigate the influence of daily electricity generation from nuclear power and renewables on the achievement of carbon neutrality targets in the four largest nuclear power countries (i.e., the U.S., China, France, and Russia). The study applies the wavelet-transform coherence (WTC), quantile-on-quantile regression (QQR), and Granger causality in quantiles (GCQ) approaches for the period from January 2, 2019 to December 29, 2022. The outcomes present that electricity generation from nuclear energy reduces carbon (CO 2) emissions only in Russia, while hydropower generation does not contribute to CO 2 emission reduction in any country. Solar electricity generation decreases CO 2 emissions in different quantiles in the U.S. and Russia, while electricity generation from wind power reduces CO 2 emissions in the U.S. and France. The empirical outcomes also reveal that expanding solar, wind, and nuclear power in the energy mix can enhance the potential of the U.S., France, and Russia to achieve carbon neutrality and secure a sustainable future. However, China is using nuclear and renewables inefficiently regarding carbon neutrality. Therefore, the empirical evidence for China is highly controversial compared to former studies. [Display omitted] • The study examines renewable and nuclear electricity effect on carbon neutrality. • The study focuses on top four major nuclear power countries. • The study applies nonlinear approaches by using high-frequency (daily) data. • Renewable and nuclear electricity have time, frequency, & quantile-varying effect. • The best electricity source change according to each country. [ABSTRACT FROM AUTHOR]

Global reproductive landscapes and with them cross-border routes are rapidly changing. This paper examines the reproductive routes and choices of fertility travellers from China to Russia as reported by medical professionals and fertility service providers. Providing new empirical data, it raises new ethical questions on the facilitation of cross-border reproductive travel and the commercialisation of reproductive treatment. The relaxation of the one-child policy in 2014 in China, the increasing demand for ART exceeding the capacity of national fertility clinics and the difficulty of accessing treatment with donor eggs concomitant with a growing economic power of the upper–middle class are shaping the ART industry in Asia in new ways. A new development is Chinese citizens increasingly seeking ART treatment in Russia, which has a long-standing practice of ART governed by a liberal legislation. Furthermore, as China prohibits the export of gametes, Chinese fertility travellers rely on acquiring donor gametes once starting treatment abroad. Clinicians in Russia report three strategies amongst their Chinese patients: One group is using donor eggs of women of Asian appearance living in Russia or is hiring women of resembling appearance from third-party countries to donate their eggs in Russia to create resemblance in their offspring. Another group is buying white donor gametes to create Eurasian mixed children and thus 'enhance' their offspring. Providing novel empirical data, this article informs ethical deliberation and raises imminent questions for further research in this understudied geographic region and on cross-border reproductive treatment. [ABSTRACT FROM AUTHOR]

The first-order grey model is appropriate for monotonic time series, while the grey Verhulst model is appropriate for periodic time series. The grey Verhulst model is widely used for predicting practical nonlinear time series that contain fluctuations. Despite the successful application of the grey models in practice, researchers show that grey models still have room for improvement. Moreover, recent research shows that grey models are sensitive to initial conditions. In many practical problems, the value of initial conditions is not accurate and suffers from noise or approximation errors, resulting in inaccurate prediction. To address these difficulties, an improved grey Verhulst method using particle swarm optimization is proposed in this paper. The proposed model consists of two stages. In the first stage, a second-order polynomial with unknown coefficients is used to approximate the 1- AGO. In the second stage, the initial element of the time series is modified to improve the accuracy of the prediction. The particle swarm optimization method is used to search for the unknown coefficients. It is found that PSO is a suitable optimization method for the proposed method because it is stable and generates a sequence of points that converges to a globally optimal solution. To demonstrate the efficiency and stability of the proposed method, it was applied to five practical problems, namely, gas production in China, the number of hazardous chemical accidents, CO2 emissions in Russia, the number of domestic tourists in China, and traffic flows in Canada. Numerical results show that the method is more accurate and robust than existing methods. • The proposed method needs only four elements for predicting the future elements of time series. • The paper proposes a second order polynomial for approximating 1-AGO. • The method makes more accurate prediction than existed methods. • The proposed method is applied on various practical forecasting problems successfully. [ABSTRACT FROM AUTHOR]

The present paper will briefly review several turning points in the evolution of the Post-Cold War global order. During the Cold War, the bipolar international order was defined by an opposition between two superpowers whose positions were carefully balanced across the world. By contrast, due to the fact that the global security architecture was, and continues to be, in flux, the past three decades have witnessed a gradual transition from a unipolar world characterized by weak and inconsistent American leadership, to unmitigated efforts on the part of Russia and China to establish a multipolar equilibrium of power. At the same time, the New World Order was breaking with the long-held tradition of placing the military component at the center of the global security system and proclaimed the so-called "Comprehensive Security Doctrine" in which supremacy of law, democratic values, global economic prosperity, social justice, human rights, environmental protection, education and other elements played an equally important role. The idea of undiminished and equal security for all states, big or small, although very attractive in theory, turned out difficult to attain in practice. An emphasis is placed on different models of democracy determined by cultural and traditional peculiarities of states, using the rules of democracy and elections to maintain power. [ABSTRACT FROM AUTHOR]

Central Asia, the hub of natural resources, has been the battleground of international power politics among the big powers since long. In order to have influence in the region, the Russian and the British Empires indulge in the "Great Game". However, it ended with the collapse of the Russian empire. The collapse of the Soviet Union in 1991 created an unexpected power vacuum in Central Asia followed by a fierce competition between the big three, Russia, China and US. This competition is commonly known as "The New Great Game" in the present day international politics. The rich energy resources are usually considered the main reason of the renewed interests in the region and provide principal motivation for Russia, China and US. However, the role of energy resources is usually overstated. This paper will identify which other factors along with energy resources should be considered in order to have a broader and comprehensive understanding of the present Geo-political scenario in the Central Asia. Using the Neo-Realist approach, this paper will first analyze the significance of the Central Asian states, how they provoke strategic competition between great powers and how pipeline politics translate it. Finally, the paper will analyses the competing interests of Russia, China and US and the strategies adopted by each for the achievements of its objectives. It will be concluded by stating that how Russia, China and US struggle to attain, keep and enhance power and that energy resources are just a mean to this supreme objective. It will also conclude by asserting that although the great powers behave aggressively and self-interestedly they may find a minimum degree of cooperation to tackle common concerns such as a growing radical Islamism. [ABSTRACT FROM AUTHOR]

In-situ monitoring system is absolutely necessary for a long-distance linear pipeline infrastructure in permafrost regions due to the complicated interaction between buried pipeline and its harsh permafrost environment. To study this complex problem, a comprehensive in-situ monitoring system has been designed and established along the China–Russia Crude Oil Pipeline (CRCOP), which is one of vital energy channels for importing crude oil from Russia to China. This monitoring system can record the meteorological data, ground temperature and water content within the permafrost foundation, vertical settlement of the oil pipe, ground surface deformation on the pipeline right-of-way (on-ROW), as well as the thaw bulb around the pipeline at four sites with different engineering geological conditions. In this paper, the layout and instrumentation of the whole monitoring system and monitoring methods are described in detail, and then the thermal regime of permafrost on-ROW and off-ROW and cooling performance of the mitigative measures on foundation soils are evaluated. Results show that heat dissipated from the CRCOP lead to the rapid degradation of permafrost on-ROW and produce different sizes of thaw bulb around the oil pipelines. The mitigative measures, including insulation layer, two-phase closed thermosyphon and U-shaped air-ventilated pipes, are effective to minimize permafrost degradation and ensure the thermal stability of permafrost foundation along the CRCOP. Some recommendations are proposed for future research and for the monitoring system to be improved. This monitoring system can provide multi-field data to clarify the interaction between pipeline and permafrost degradation under different geological conditions, and guide the design and maintenance of the buried warm pipeline in permafrost regions. • An in-situ monitoring system is set up along the CRCOP in permafrost regions. • The geological characteristics and layout of instrumentation at four monitoring sites are reported. • The integrated monitoring method for pipeline-permafrost interaction are presented. • Thermal effect of buried warm oil pipe on underlying permafrost is observed. • Cooling performance of the insulation layer, thermosyphon and U-shaped air-ventilated pipes is evaluated. [ABSTRACT FROM AUTHOR]

The accurate and reasonable prediction of natural gas consumption is important for enhancing national energy security and alleviating the environmental problems caused by energy consumption. Starting with the traditional nonlinear grey Bernoulli model, in this paper, we expand the development coefficient a and grey action quantity b, propose a new self-adaptive time-varying grey Bernoulli prediction model, deduce the time response formula of the model, and explore the relationship between model parameters and model accuracy. Then, the nonlinear parameter and power parameter coefficient of the new model are optimized by a genetic algorithm, and the effectiveness of the model is analyzed by the natural gas consumption of China, the United States, and Russia. The results show that, compared with other traditional grey prediction models, the new model has a better simulation effect, higher prediction accuracy, and stronger applicability. Meanwhile, the model was used to forecast the natural gas consumption of China, the United States, and Russia in the period from 2022 to 2026. The prediction results show that China's natural gas consumption will continue to steadily increase in the future, which is consistent with the global goal of adhering to the orderly development of natural gas. The prediction results can provide a theoretical basis for relevant departments to formulate relevant natural gas policies. [ABSTRACT FROM AUTHOR]

Rapid permafrost thawing triggered by heat release from the buried warm-oil pipeline would result in the instability of the pipeline, posing a potential risk of an oil spill in permafrost regions. Therefore, how to precisely control the ground temperature to mitigate pipeline foundation permafrost from thawing is of significant importance. Thermosyphon is a widely-accepted and extensively-used countermeasure against permafrost thawing in permafrost engineering. This paper presents 3-year (2015–2018) monitored data of ground temperature and geophysical survey results conducted by electrical resistivity tomography in April 2018, to investigate the thermal stabilizing effect of thermosyphons installed nearby the China-Russia crude oil pipeline (CRCOP) and the influencing factors. Furthermore, numerical simulation tests were conducted to evaluate their long-term cooling applicability and to optimize their layout parameters. Field observations show that the thermosyphons can cool down and even freeze the thawed soil layers around the CRCOP, prohibiting the infiltration of water into the thawing front to some extent and effectively mitigating the rapid thawing of permafrost beneath the pipeline. The performance of the thermosyphons is greatly influenced by the method and time of thermosyphon installation, as well as layout parameters including the number and longitudinal spacing. Two pairs of thermosyphons with a shorter spacing are unable to control the thawing of the underlying permafrost due to the non-anticipated higher oil temperature, the thermal erosion of water ponding, and climate warming. The simulated results indicate that thermosyphons perform well in the first 5 years after installation. Thermosyphon lowers the mean annual temperature of soils surrounding it by about 2 and 1.4 times when the evaporator section length is increased by 50% and the longitudinal spacing is decreased by 0.5 m, respectively. The application of thermosyphons has proven its strength for thermally stabilizing the pipeline foundation permafrost along the CRCOP. • 3-year ground temperature data and geophysical survey results are presented. • Thermosyphon can mitigate the rapid thawing of permafrost beneath the pipeline. • Thermosyphons performs most significantly in the first five years. • Lengthening thermosyphon and decreasing spacings are favorable for the better cooling effect. [ABSTRACT FROM AUTHOR]

In this paper, we examine patterns of self-reported diagnosis of noncommunicable diseases (NCDs) and prevalences of algorithm/measured test-based, undiagnosed, and untreated NCDs in China, Ghana, India, Mexico, Russia, and South Africa. Nationally representative samples of older adults aged ≥50 years were analyzed from wave 1 of the World Health Organization's Study on Global Ageing and Adult Health (2007-2010; n = 34,149). Analyses focused on 6 conditions: angina, arthritis, asthma, chronic lung disease, depression, and hypertension. Outcomes for these NCDs were: 1) self-reported disease, 2) algorithm/measured test-based disease, 3) undiagnosed disease, and 4) untreated disease. Algorithm/measured test-based prevalence of NCDs was much higher than self-reported prevalence in all 6 countries, indicating underestimation of NCD prevalence in low- and middle-income countries. Undiagnosed prevalence of NCDs was highest for hypertension, ranging from 19.7% (95% confidence interval (CI): 18.1, 21.3) in India to 49.6% (95% CI: 46.2, 53.0) in South Africa. The proportion untreated among all diseases was highest for depression, ranging from 69.5% (95% CI: 57.1, 81.9) in South Africa to 93.2% (95% CI: 90.1, 95.7) in India. Higher levels of education and wealth significantly reduced the odds of an undiagnosed condition and untreated morbidity. A high prevalence of undiagnosed NCDs and an even higher proportion of untreated NCDs highlights the inadequacies in diagnosis and management of NCDs in local health-care systems. [ABSTRACT FROM AUTHOR]

In permafrost regions, the soil settlement disaster owing to permafrost degradation has become one of the important reasons for buried warm-oil pipelines failure. In this paper, the 3D sequential thermo-mechanical coupled model is carried out to investigate the interaction between buried warm-oil pipeline and surrounding permafrost. The effects of parameters, including thaw-settlement coefficient, length of transition zone, diameter-thickness ratio and internal pressure, on the pipeline mechanical behavior are numerically investigated. Among them, the thaw-settlement coefficient and length of transition zone present more significant effects on the peak strain of the pipeline. In addition, the effects of insulation layer and two-phase closed thermosyphon (TPCT) on pipeline–soil interaction are investigated in thermal and mechanical fields. With no protective measure, the permafrost layer under pipeline will completely degrade in about 20 years with 0.33m/a. The pipeline is considered to reach failure limitation even within 10 years. However, under the influence of combined measure, the permafrost degradation rate is only about 1/10 of that without protective measure. The peak compressive strain is significantly lower than the critical compressive strain, and the pipeline remains safe for 50 years. Therefore, the combined measure is an ideal method for ensuring pipeline safety in permafrost regions. • Permafrost layer is well protected by the combined measure. • The TSC and the LTZ show significant effects on the peak strain of pipeline. • Pipeline remains safe for 50 years under the influence of combined measure. [ABSTRACT FROM AUTHOR]

This paper takes both value-added trade and trade-implied CO 2 emission reduction responsibility into account, which constructs a unified conceptual framework to recalculate CO 2 emission reduction responsibility from the perspective of value-added trade. This allows policymakers to trace worldwide CO 2 emissions at multiple levels of trade, production, consumption, and shared principle alongside the world trade network. This paper employs the gross export decomposition methodology and the World Input-Output Database for calculations. Firstly, compared with traditional trade statistics, measuring embedded emissions in value-added trade can deduct the double-counted terms of CO 2 emissions due to intermediate products crossing several borders repeatedly. Secondly, the worldwide inter-country CO 2 emission footprints embedded in exports, imports, and net flows of value-added trade are traced in a geographical world map. It occurs that, China, the USA, Russia, and the EU are the top four largest emitters. Thirdly, network analysis is further utilized to capture bilateral implicit CO 2 emission relationships, e.g., the EU members' environmental impacts depend on intra-regional trade within the union. Finally, a comparison is made under three burden-sharing principles based on value-added trade. The shared responsibility offers a compromise between the producer's and the consumer's principle, which is considered to be fairer and more effective. • This paper calculates trade-implied CO 2 emission reduction responsibility from the perspective of value-added trade. • A gross export decomposition model is applied to deduct double-counted terms of implicit carbon embedded in traditional trade. • The worldwide inter-country CO 2 emission footprints are visualized. • Network analysis is conducted to identify the major carbon emitters and their complex relations. • Three burden-sharing criteria are computed through the statistics of value-added trade. [ABSTRACT FROM AUTHOR]

Testing ecological models involves using independent data on model performance, which can be difficult or practically impossible to obtain. Individual based models of forest dynamics, or gap models, simulate the change of forests by computing the annual growth, birth and death of each tree at a location in a forest. The models are relatively simple and simulate results that can be translated to multiple response scales: Individual plant growth, population birth-death processes, stand environmental dynamics ( e.g ., evapotranspiration, element cycling, heat flux, etc .), landscape processes, and regional and global change. This paper reviews some of the approaches applied to testing gap models. Then, it demonstrates the testing of the performance of an individual-based gap model of forest dynamics, FAREAST, through comparison against independent data from China and across Russia. As part of this model testing, biomass simulation output for 93 locations is compared to independent field-collected inventory-data from 44 Russian forests, which span a broad range of forest types across Russia. FAREAST captures biomass dynamics and stabilization at specific locations bracketing the measured values. At Changbai Mountain, the model accurately predicts the community dynamics of complex mixed forest types present along an elevational gradient, as well as the broad regional compositional patterns across China and Russia. Validation of regional detailed landscape dynamics shows the model performs with fidelity with an average R2 value of 0.74 for 87 comparisons and an average root mean square error of 10.8 tC ha −1. Performance of the model for historical conditions implies the model's applicability across a broad region and suggests the usefulness of a detailed model for evaluating forest change to management and changing climate. [ABSTRACT FROM AUTHOR]

Comparative evaluation of cross-boundary wetland protected areas is essential to underpin knowledge-based bilateral conservation policies and funding decisions by governments and managers. In this paper, wetland change monitoring for the Wusuli River Basin in the cross-boundary zone of China and Russia from 1990 to 2015 was quantitatively analyzed using Landsat images. The spatial-temporal distribution of wetlands was identified using a rule-based object-oriented classification method. Wetland dynamics were determined by combining annual land change area (ALCA), annual land change rate (ALCR), landscape metrics and spatial analysis in a geographic information system (GIS). A Mann–Kendall test was used to evaluate changing climate trends. Results showed that natural wetlands in the Wusuli River Basin have declined by 5625.76 km2 in the past 25 years, especially swamp/marsh, which decreased by 26.88%. Specifically, natural wetlands declined by 49.93% in the Chinese section but increased with an ALCA of 16.62 km2/y in the Russian section during 1990–2015. Agricultural encroachment was the most important reason for the loss and degradation of natural wetlands in the Wusuli River Basin, especially in China. Different population change trends and conservation policies in China and Russia affected natural wetland dynamics. The research offers an efficient and effective method to evaluate cross-boundary wetland change. This study provides important scientific information necessary for developing future ecological conservation and management of cross-boundary wetlands. [ABSTRACT FROM AUTHOR]