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This comparative study of streaming services in different cultural and economic contexts shows how they optimize the user experience by improving recommendation algorithms, upgrading infrastructure, and developing global services, in responding to the crisis of losing subscribers.

Simple Summary: Methanogens are a group of microorganisms with the capability to convert inorganic or organic compounds into methane, impacting the global carbon cycle and greenhouse gas emissions. In anaerobic environments such as wetlands, paddy fields, and reservoirs, methanogens are the primary contributors to methane production. In this study, high-throughput sequencing of the mcrA functional gene was utilized to conduct a comprehensive analysis of the community structure, metabolic pathways, and influencing factors of methanogens in the sediment of 18 reservoirs on the northeastern Qinghai Plateau. The results indicated that the construction of reservoirs has altered the physicochemical properties of river water and sediments, significantly impacting the distribution and succession of methanogenic communities in the sediment. In general, this study can improve our understanding of the biological mechanisms of methane emissions from the reservoirs on the Qinghai Plateau. Reservoirs are a hotspot for methane emissions, a potent greenhouse gas. However, the microbial basis for methane production in the Qinghai Plateau reservoirs remains unclear. To explore the characteristics of methanogenic communities in reservoir sediments on the northeastern Qinghai Plateau, sediment samples were collected from 18 reservoirs in the Yellow River basin during May 2023 (dry season) and August 2023 (wet season). High-throughput sequencing technology was employed to analyze the community composition, diversity, and co-occurrence network of methanogens. Furthermore, FAPROTAX and Mantel analysis were used to assess the metabolic functions of methanogens and their influencing factors. The results showed that (1) the predominant genera of methanogens were Methanobacterium (28.87%) and Methanosarcina (21.67%). Hydrogenotrophic methanogenesis was the main pathway in the sediments. (2) Significant spatiotemporal differences were observed in the diversity of methanogenic communities (p < 0.05). The composition and diversity of these communities were found to be significantly influenced by temperature, pH, altitude, organic carbon, and total nitrogen (p < 0.05). (3) Methanosarcina, Methanobacterium, and Methanospirillum play crucial roles in maintaining the stability of methanogenic community networks. The co-occurrence network nodes are predominantly positively correlated (99.82%). These results provide data for further studies on carbon cycling in the Qinghai Plateau reservoirs. [ABSTRACT FROM AUTHOR]

The evolution of the mechanical properties of slip zone soils had a greater impact on the structure of soil slopes with large upper porosity and excellent infiltration conditions. Especially under the rainfall effect, it was easy to be affected by the infiltration effect of internal injury, which will lay a ‘hidden danger’ for the slope body to trigger sliding in the secondary transformation process. In this paper, based on Haijiao ping landslide in Guizhou, SEM image recognition techniques were used to reveal the water-induced degradation mechanism of the sliding zone soil from multiple scales and the damage parameters were obtained. Meanwhile, the FDEM numerical model was established to simulate the stability of the slope coupled with indoor TCT test results. The results proved that the angle of internal friction decreased linearly with the increase of water content on the macroscopic scale, but the cohesive force showed an increase and then a significant decrease. The effect of matrix suction in the microscopic scale was significant at lower water content, the internal cohesion formed a large number of agglomerate structures to resist external deformation, but the microstructure was loose and porous after sufficient water immersion. The pore space spreads directionally and the area increases by 2.66 times. The cross-scale discrete-finite element coupled simulation method based on image recognition can visually respond to the macroscopic mechanical properties and stability change response of the slope body caused by microscopic damage. The water-induced degradation effect of rainfall on slip zone soils was the inherent factors for the initiation deformation of landslide. The artificial excavation was the external factor that triggered the slope to slide. This type of landslide was more concealed in its natural state and prone to deformation when excavated after long-term rainfall.

Drought is one of slow onset natural hazards with great impacts in many aspects, such as economy, agricultural and human health. To well manage drought, the areal coverage, duration and frequency can be analyzed and estimated to provide insight into historical perspective of drought events as well the long-term variation of climate in the study area. This study tries to explore the natural of drought including its definitions, categories, trigger mechanism and possible mitigation methods. This research studies the drought characteristics in Wyoming, United States based on the rainfall data from the U. S Historical Climatology Network (USHCN). The main approach is Standardized Precipitation Index (SPI), which provides the means to analyze drought at different time scales and discusses the relationship between drought and climate change.

Understanding variation in assemblage composition (i.e., beta diversity) along geographic and environmental gradients is a central topic in biogeography and ecology. We compared relationships between hemipteran beta diversity (overall dissimilarity: βtotal, Sorensen dissimilarity; turnover component: βsim, the replacement of species between assemblages; nestedness‐resultant component: βsne, the nested difference in richness between assemblages) and geographic, climatic and land cover distances among four ecoregions (Northeast Ecoregion; Northern Ecoregion; Tibet Ecoregion; Southern Ecoregion) across China. The hemipteran assemblage composition differed markedly among ecoregions. In general, βtotal and βsim both significantly increased with increasing geographic, climatic and land cover distances. Intercepts and slopes of dissimilarity‐distance relationships all varied significantly among different ecoregions, suggesting different levels of within‐ecoregion assemblage heterogeneity and change rate in assemblage composition. Moreover, the slopes of βtotal and βsim were highest in Northeast Ecoregion but lowest in Northern Ecoregion, exhibiting latitudinal and longitudinal dissimilarity pattern. According to variation partitioning analysis, although the overall explained variance was relatively low, spatial variables explained a much greater proportion of variance compared to climate and land cover variables. To conclude, our results showed significant regional differences in assemblage composition and biodiversity among ecoregions. Both dispersal‐related and niche‐related processes affect hemipteran assemblage structure, while the low overall explained variance indicates that high dissimilarity in hemipteran composition is affected by multiple factors and processes that remained undetected in this study. Our results may be relevant for wider insect groups because hemipterans constitute a highly diverse group in terms of phylogenetic origins and functional significance. [ABSTRACT FROM AUTHOR]

Rapid urbanization and industrial development in the eastern region of the Qinghai‐Tibetan Plateau is imposing significant and interdependent pressures on food, energy, and water. A long‐term assessment of the regional water balance reveals a complex interaction of factors that are altering the available water, including changes in the locally grown food supply and hydropower generation. Within the main watershed of Xining City, increasing urbanization results in increased runoff to streams and increased withdrawals from surface water reservoirs. Withdrawals have also been increasing as a result of growth in irrigated agriculture. A hydrologic modeling approach on a watershed scale was used to analyze the long‐term implications of these factors and to quantitatively assess the trade‐offs between water supply and food production within this semi‐arid watershed. The policy implications of the findings in a Food‐ Energy‐Water nexus framework for the region will be provided to regional decision makers to aid in future watershed management. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 62–72, 2018 [ABSTRACT FROM AUTHOR]

A four-beam slot array antenna, which has a cylinder conformal structure based on substrate integrated waveguide (SIW) technology, is designed and fabricated for the first time. Through the commercial software Microwave Studio Office CST optimization of the flat structure parameters, which are calculated using the planar SIW slots array antenna and Butler Matrix design method, the parameters of conformal structure are obtained. The fabricated phase array offers four beams with 16 dB gain at Ku band. The sweep range is around 160 degrees over azimuth direction. Meanwhile, the level of side lobes is reduced as low as -12 dB for all beam in E-plane. The usable bandwidth of the antenna is 3.5% at 11.5 GHz. [ABSTRACT FROM AUTHOR]

Urban wetlands, an important part of the urban ecosystem, play an important role in regional carbon cycles and the carbon balance. To analyze the CO2 source and sink effects of plateau urban wetlands, based on the data measured by an eddy covariance instrument, the temporal and spatial characteristics of CO2 flux and their influencing factors in the urban wetland of Xining City in the Qinghai Province of China during a warm season (July to September 2020) were studied. The results show that: (1) On the daily scale, the CO2 flux exhibited an obvious "U"-type variation, characterized by strong uptake in the daytime and weak emission at night, with an average daily flux of −0.05 mg·m−2·s−1. The CO2 uptake peak of the wetland took place at 13:00 (−0.62 mg·m−2·s−1), and the emission peak occurred at 23:30 (0.34 mg·m−2·s−1); (2) on the monthly scale, the CO2 flux of the wetland in the study period showed a net uptake each month. The flux increased month by month, and the maximum value occurred in September (−142.82 g·m−2·month−1); (3) from a spatial point of view, the river area showed a weak CO2 uptake (−0.07 ± 0.03 mg·m−2·s−1), while the artificial wetland area showed a strong CO2 uptake (−0.14 ± 0.03 mg·m−2·s−1). The former was significantly lower than the latter (p < 0.01); (4) the regression analysis results show that the CO2 flux was significantly correlated with PAR, VPD, Tsoil, and SWC (p < 0.01). The relationships between the flux and PAR, Tsoil, and SWC were rectangular hyperbola (y = 0.2304 − 2 × 10−3x/(0.9037 + 0.0022x), R2 = 0.64), exponential (y = 0.046exp(0.091x), R2 = 0.88), and quadratic (y = −0.0041x2 + 0.1784x − 1.6946, R2 = 0.83), respectively. Under the joint action of various environmental factors, the urban wetland ecosystem in plateau displayed a strong carbon sink function in warm seasons. This study can establish a data scaffold for the accurate estimation of carbon budget of this type of ecosystem. [ABSTRACT FROM AUTHOR]

Background: Cold agglutinins (CAs) in blood samples can cause a reversible agglutination of red blood cell (RBC) which result in an incorrect complete blood count (CBC). So, it is important to explore new simple and feasible treatment conditions for clinical work., Methods: The CAs group included 32 samples with CAs. The parameters of CBC at room temperature or after prewarming at 37°C or 41°C for different time periods were compared. The consistency and correlation of those parameters were analyzed. The morphology of erythrocytes in the CAs group was observed manually. The control group included 45 samples without CAs and prewarmed at 37°C or 41°C for different time periods. The differences were also analyzed., Results: CAs have a significant effect on CBC. After prewarming at 37°C or 41°C the interferences are all corrected. Consider prewarming at 37°C for 120 minutes as the standard procedure. The consistency and correlation analysis showed there was no statistical difference between the results of each subgroup and standard group, except the MCHC of group 41°C 10 minutes. The correlation of parameters between all subgroups and the standard group is satisfied. Microscopic examination showed no RBC aggregation or fragmentation after prewarming at 41°C or 37°C. According to the maximum bias requirements for expert performance in Validation, Verification, and Quality Assurance of Automated Hematology Analyzers, 2nd Edition (CLSI H26-A2), the differences in overall results in control group are negligible., Conclusions: The 41°C 2 minutes prewarming method is a rapid and effective way for treating samples with CAs. It is an efficient way to obtain more reliable CBC results, without specific instruments.