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Litter input is a critical link between the circulation and flows of energy and matter in forest ecosystems. Drought events impact litter inputs, affecting forest ecosystems’ nutrient and energy cycles. To investigate the response of litter production to extreme drought, explore their recovery mechanism, and the difference between whole year, concurrent drought, non-drought period, rainy season, and dry season. We studied an extreme drought event in a subtropical evergreen broadleaved forest in the Ailao Mountain in 2009–2010. We used 10 years (2005–2014) of monthly litter production and climate data, including monthly average precipitation (MAP), soil water content (SWC), and monthly average temperature (MAT). The observation period was separated into pre-drought (2005–2008), during-drought (2009–2010), and post-drought (2011–2014) periods. We found that annual total litter production decreased by 12 % during the drought (p

Large scale bilateral transactions may lead to extreme power grid operation mode. The trading results adjustion by post security check may affect the generation plans and increase the production and operation risks of market members. It is of great significance for the orderly development of power market in the medium and long-term to provide the security analysis service before the transaction process and guide the market members to revise the medium and long-term physical transactions. A new mode of medium and long-term electricity security analysis based on market members' transaction willingness is proposed. In the mode, a two-step security check process including centralized electricity security analysis and electric energy limitation calculation is established, and an optimization analysis model based on security-constrained unit commitment (SCUC) is developed. Through coordinating the multi-period optimal dispatching of power balance and power grid security, it is available to acquire the executable conclusion of electricity contract as well as the subsequent power tradable space. The case analysis based on actual data of provincial power grid shows the effectiveness of the mechanism.

Silty clay can be found in the alpine region of the Qinghai province, China, where it is subject to annual freeze-thaw cycles. To investigate the static mechanical properties of silty clay modified by basalt fiber and basalt powder under the action of freeze-thaw cycles, triaxial compression tests and scanning electron microscope tests were conducted on the soil. The test results revealed that varying the number of freeze-thaw cycles resulted to different effects on the soil mechanical strength, which tended to increase after 2 cycles, but then tended to decline when subjected to 5–10 cycles. After 20 freeze-thaw cycles, soil strength reached a dynamic equilibrium state. The shear strength of basalt fiber soil and basalt powder soil increased by 7.55% and 5.12%, respectively, compared with that of normal soil under 30 freeze-thaw cycles. Subsequently increasing of the number of freeze-thaw cycles differentially affected the cohesion and internal friction angle of normal soil and admixture soils, and these soils gradually tended to stabilize at a mechanical strength higher than the initial value. Basalt fibers reinforced the soil to a higher degree than basalt powder at a dosage of 0.4% based on dry soil mass. The stress-strain curves of the three soil types can be simulated using the hyperbolic model. The results of the study can provide some theoretical reference for practical engineering in seasonal frozen soil areas.

As the national policy encourage to reduce the fuel consumption and oil prices rising gradually,to reduce fuel consumption of the vehicle is widely concerned.The fuel consumption is closely related to the transmission efficiency,and the rear axle plays an important role in auto transmission system and different lubricant has a great influence on the transmission efficiency of rear axle,the viscosity of the lubricant,the losses of gear meshing and churning losses are analyzed,a lot of experiments are conducted to investigate the influence of viscosity of lubricant on transmission efficiency of rear axle.It is found that relatively low viscosity lubricant contributes to improving the transmission efficiency of rear axle and makes an important significance on reducing vehicle fuel consumption.

Diffuse optics (DO) is a light-based technique used to study the human brain, but it suffers from low brain specificity. Interferometric diffuse optics (iDO) promises to improve the quantitative accuracy and depth specificity of DO, and particularly, coherent light fluctuations (CLFs) arising from blood flow. iDO techniques have alternatively achieved either time-of-flight (TOF) discrimination or highly parallel detection, but not both at once. Here, we break this barrier with a single iDO instrument. Specifically, we show that rapid tuning of a temporally coherent laser during the sensor integration time increases the effective linewidth seen by a highly parallel interferometer. Using this concept to create a continuously variable and user-specified TOF filter, we demonstrate a solution to the canonical problem of DO, measuring optical properties. Then, with a deep TOF filter, we reduce scalp sensitivity of CLFs by 2.7 times at 1 cm source-collector separation. With this unique combination of desirable features, i.e., TOF-discrimination, spatial localization, and highly parallel CLF detection, we perform multiparametric imaging of light intensities and CLFs via the human forehead.

The field of diffuse optics has provided a rich set of neurophotonic tools to measure the human brain noninvasively. Interferometric detection is a recent, exciting methodological development in this field. The approach is especially promising for the measurement of diffuse fluctuation signals related to blood flow. Benefitting from inexpensive sensor arrays, the interferometric approach has already dramatically improved throughput, enabling the measurement of brain blood flow faster and deeper. The interferometric approach can also achieve time-of-flight resolution, improving the accuracy of acquired signals. We provide a historical perspective and summary of recent work in the nascent area of interferometric diffuse optics. We predict that the convergence of interferometric technology with existing economies of scale will propel many advances in the years to come.

Objective: This study aims to: (1) examine gender differences for weight conscious drinking among college students accounting for the broader phenomenon (e.g. including the Alcohol Effects dimension); and (2) longitudinally examine the effect of weight conscious drinking behaviors on body mass index (BMI). Participants: United States freshmen students from eight participating universities (N= 1,149). Methods: Structural equation modeling was used to model the effect of gender on weight conscious drinking dimensions at 7-month follow-up. Results: Findings suggest a significant effect of gender on Alcohol Effects ([beta] = -0.15, SE = 0.05, p = 0.005) at 7-month follow-up among college freshmen. Weight conscious drinking dimensions predicted no significant change in BMI at 7-month follow-up among college freshmen. Conclusion: Findings contribute to weight conscious drinking theory and provide campus weight conscious drinking prevention initiatives with evidence to tailor their programming to address female tendencies to engage in compensatory strategies to enhance the psychoactive effects of alcohol.

This report is the second part of a comprehensive two-part series aimed at reviewing an extensive and diverse toolkit of novel methods to explore brain health and function. While the first report focused on neurophotonic tools mostly applicable to animal studies, here, we highlight optical spectroscopy and imaging methods relevant to noninvasive human brain studies. We outline current state-of-the-art technologies and software advances, explore the most recent impact of these technologies on neuroscience and clinical applications, identify the areas where innovation is needed, and provide an outlook for the future directions.

The synergistic effects of methylphenyl-polsiloxane solid powder and organophosphate flame retardant for polycarbonate (PC) were investigated by limiting oxygen index(LOI), and cone calorimeter. It was found that the LOI of the flame-retarded PC (FR-PC) with polysiloxane and organophosphate binary flame retardants didn’t increase in comparison with that of FR-PC containing a single species flame retardant. The cone calorimeter results show that the heat release rate (HRR) of the PC/polysiloxane/organophosphate(PX230) composition is approximately 50% lower than that of the PC/polysiloxane or the PC/PX230. Total heat release (THR) of PC/polysiloxane/PX230 also significantly reduce in comparison with that of PC/polysiloxane and PC/PX230 binary composites, which indicates a clear synergistic effect of the polysiloxane and PX230 in the PC flame retardant composites. The CO production rate of the PC/polysiloxane/PX230 during combustion is slightly lower than that of the virgin PC. So the combination of the polysiloxane with PX230 used in PC could synergic inhibit the combustion heat release, and achieve environmental friendly fire-retardant effect.