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A flash drought typically exhibits rapid development and high intensity, with significant impacts on societies and ecosystems. Central Asia (CA), a typical arid region, little attention has been paid to the characteristics of flash droughts and their impact on ecosystems. Therefore, a novel composite decomposition flash drought identification (CDFDI) framework was adopted to integrate data on soil moisture, normalized difference vegetation index (NDVI), and gross primary productivity to identify flash drought as a subphase of regular drought in CA. This study aims to explore flash drought characteristics and vegetation response in CA, comparing them with existing identification methods to assess the effectiveness of the flash drought identification framework. The main findings are: (1) introducing inter-event time and volume criterion and Madsen methods in the CDFDI framework yielded promising results, verified through correlation between flash drought characteristics and NDVI deficits (e.g., the average percentage of correlations between flash drought features and NDVI in the − 1 to -0.5 and 0.5 to 1 intervals was 15%); (2) the northern, central, eastern, and southeastern CA were frequently affected by flash droughts, while the western region experienced prolonged regular droughts with an insignificant weakening trend between 1948 and 2022; and (3) Average gross primary productivity response time was 30 days, and its spatial distribution indicated that the impacts of flash drought on vegetation were more immediate in the comparatively arid western CA. This study provides new insights into identifying and characterizing flash drought in changing environments, contributing to a better understanding of its impacts on ecosystems. [ABSTRACT FROM AUTHOR]

This study explores a spatial piecewise approach for the hedonic valuation of the area of urban green space at different distances from a property, using a rich census dataset collected from Beijing. We explore three novel empirical strategies that improve the identification of the spatial boundary or threshold distance within which green space is capitalised into housing prices. We first delineated a series of concentric circles surrounding each property and measured the area of green space within each doughnut-shaped ring. We next estimated the hedonic price using three methods. The first is a regression spline model combined with a machine learning type of model selection procedure which objectively selects the exact location of the threshold distance that optimises the model's predictive performance. The second is a novel matching algorithm that minimises covariate imbalance for a continuous treatment variable (i.e., the area of green space) to provide stronger causal evidence on the hedonic prices of green space at different distances. The third is a spatial difference-in-differences approach that further accounts for endogeneity bias associated with unobserved factors. For our dataset, we found that housing prices are more likely to be affected by green space within a 1 km radius. [ABSTRACT FROM AUTHOR]

The clinical significance of the combination of neutrophil–lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) is unclear. This study investigated the predictive value of pretreatment NLR (pre-NLR) combined with pretreatment PLR (pre-PLR) for the survival and prognosis of nasopharyngeal carcinoma (NPC). A total of 765 patients with non-metastatic NPC from two hospitals were retrospectively analyzed. The pre-NLR-PLR groups were as follows: HRG, high pre-NLR and high pre-PLR. MRG, high pre-NLR and low pre-PLR or low pre-NLR and high pre-PLR. LRG, neither high pre-NLR nor high pre-PLR. Receiver operating characteristic (ROC) curves were used to identify the cutoff-value and discriminant performance of the model. We compared survival rates and factors affecting the prognosis among different groups. The 5-year overall survival (OS), local regional recurrence-free survival (LRRFS) and distant metastasis-free survival (DMFS) of NPC patients in HRG were significantly poorer than those in MRG and LRG. The pre-NLR-PLR score was positively correlated with T stage, clinical stage, ECOG, and pathological classification. Multivariate cox regression analysis showed that pre-NLR-PLR scoring system, ECOG, pre-ALB, pre-CRP and pre-LMR were independent risk factors affecting 5-year OS, LRRFS and DMFS. The ROC curve showed that area under the curve (AUC) values of pre-NLR-PLR of 5-year OS, LRRFS and DMFS were higher than those of pre-NLR and pre-PLR. pre-NLR-PLR is an independent risk factor for the prognosis of NPC. The pre-NLR-PLR scoring system can be used as an individualized clinical assessment tool to predict the prognosis of patients with non-metastatic NPC more accurately and easily. [ABSTRACT FROM AUTHOR]

The Yellow River Basin (YRB) is a vital ecological zone in China owing to its sensitive and fragile environment. Under the long-term influence of climate changes and artificial factors, the relationship between precipitation, vegetation, and surface water in the YRB has changed drastically, ultimately affecting the water resources and environmental management. Therefore, we applied multivariate statistical analysis to investigate the precipitation, normalized difference vegetation index (NDVI), and surface water changes in the YRB from 2000 to 2021. Furthermore, we attempted to clarify the ecological effects of precipitation by explaining the relationship between precipitation and vegetation in terms of the time-lag relationship using the Integrated Multi-satellite Retrievals for Global Precipitation Measurement algorithm, Moderate Resolution Imaging Spectroradiometer, and hydrological databases. Precipitation, vegetation, and area of surface water in the YRB showed increasing trends from 2000–2021 (e.g., 7.215 mm/yr, 0.004 NDVI/yr, and 0.932 km2/yr, respectively). The water level in the upper reaches of the YRB showed a downward trend, whereas that in the middle and lower reaches exhibited an upward trend. Changes in precipitation had a positive effect on vegetation and surface water in the YRB, with correlation coefficients of 0.63 and 0.51, respectively. The responses of NDVI and surface water elevation to precipitation were heterogeneous and delayed, with the majority showing a lag time of approximately ⩽ 16 days. Moreover, the lag times of Longyangxia Lake and Ngoring-Co Lake were 0 and 8 days, respectively. We showed that precipitation variability can effectively explain vegetation improvement and increases in surface water elevation, while providing a proven scenario for predicting the surface water and vegetation productivity under the influence of climate change. [ABSTRACT FROM AUTHOR]

Global warming has severely affected the climate in the Yangtze River Basin (YRB), resulting in complex and varying meteorological and hydrological processes. Therefore, identifying the effects of climate change in the YRB is important for characterizing the affected meteorological and hydrological processes. In this study, the characteristics of climate equilibrium were analyzed and the natural drivers of climate change in the YRB were explored using precipitation and temperature data from 1961 to 2018. The major findings can be summarized as follows. (1) Significant spatial and temporal differences in precipitation and temperature occurred. For example, annual precipitation showed a decreasing trend in the middle reaches but a significant increasing trend in the headwaters area and lower reaches. Between 1981 and 2001, annual precipitation and temperature exhibited overall increasing trends as well as abrupt changes. (2) Temporal changes in precipitation were primarily low in the middle and lower reaches and high in the headwater region of the YRB, although a low precipitation concentration degree (CD) occurred in summer in the upper reaches. High temperature changes over time mainly occurred in the headwater region of the YRB, although a high temperature CD occurred in winter in the northern parts. (3) Different teleconnection indices affected precipitation and temperature in different seasons. In particular, the Niño 3.4, North Atlantic Oscillation, and North Pacific Index had a significant influence on precipitation and temperature. This study provides critical information for revealing the changes in meteorological and hydrological processes and potential influencing factors in the YRB. [ABSTRACT FROM AUTHOR]

The aim of this study was to identify the aggregation sites and transmission characteristics of Gasterophilus pecorum, the dominant pathogen of endangered equines in desert steppe. Therefore, we tested with a four-arm olfactometer the olfactory response of the G. pecorum adults to the odors that have a great impact on their life cycle, and also investigated the occurrence sites of the adults in the area where the Przewalski's horse (Equus przewalskii) roam frequently during the peak period of G. pecorum infection. The results of four-directional olfactory test showed that the fresh horse feces had a stronger attraction rate on both male (50.4%) and female flies (38.2%). Stipa caucasica, the only oviposition plant where G. pecorum lay eggs, had a better attraction effect on females than that on males. And the attraction rates of S. caucasica to G. pecorum females in the early growth stage (Stipa I) and mid-growth stage (Stipa II) were 32.8% and 36.8%, respectively. In addition, the two-directional olfactory test showed that the attraction rate of males to fresh horse feces (68.90%) was higher than that to Stipa II (31.10%), and females also showed similar olfactory responses. Moreover, in our field investigation, 68.29% of G. pecorum adults were collected from around the horse feces. The results of laboratory test and field investigation implied that the location mechanism of G. pecorum aggregation for mating is related to the orientation of horse feces. The horse feces and the vicinity are the key contamination areas of G. pecorum, and it is also the areas where horses are seriously infected with G. pecorum. Those fresh feces, which gather abundant information about the host, naturally had the greatest chance of contacting with the host; G. pecorum adults create the opportunity to enter directly into the host's mouth and infect the host by laying eggs on S. caucasica, which is the most favorite plant of the host in this area. These characteristics are one of the main reasons why G. pecorum has become the dominant species under the condition of sparse vegetation in desert steppe. [ABSTRACT FROM AUTHOR]

Optical phase modulators are essential to large-scale integrated photonic systems at visible wavelengths and are promising for many emerging applications. However, current technologies require large device footprints and either high power consumption or high drive voltages, limiting the number of active elements in a visible-spectrum integrated photonic circuit. Here, we demonstrate visible-spectrum silicon nitride thermo-optic phase modulators based on adiabatic micro-ring resonators that offer at least a one-order-of-magnitude reduction in both the device footprint and power consumption compared with waveguide phase modulators. Designed to operate in the strongly over-coupled regime, the micro-resonators provide 1.6π phase modulation with minimal amplitude variations, corresponding to modulation losses as small as 0.61 dB. By delocalizing the resonant mode, the adiabatic micro-rings exhibit improved robustness against fabrication variations: compared with regular micro-rings, less than one-third of the power is needed to thermo-optically align the resonances of the adiabatic micro-rings across the chip to the laser frequency. Visible-spectrum silicon nitride thermo-optic phase modulators based on adiabatic micro-ring resonators with a small device footprint and low power consumption, of potential use for applications like augmented-/virtual-reality goggles, quantum information processing circuits and optogenetics, are presented. [ABSTRACT FROM AUTHOR]

Presently, the Internet of Things (IoT) and big data analytics technology offer enormous opportunities to disaster risk management services. Recent disaster risk management patterns involve disaster risk reduction to avoid future disaster risks, minimize current disastrous risks, resilience building, and disaster loss reduction. The main challenges in disaster management are communication within a disaster zone which is being disrupted. In this paper, the Internet of Things assisted disaster risk management framework (IOTDRMF) has been proposed for technical resources to communicate the emergency time and better visibility into reliable and prompt decision-making through observing, evaluating, and forecasting natural disasters. This IOTDRMF utilizes big data analytics to analyze disaster risk management build a kind of spatial data communication network infrastructure, making it a priority to establish rules, protocols, and knowledge sharing. The experimental results show the IOTDRMF, and big data analytics compensate for a weak communication network infrastructure and better decision-making to handle disaster risk management. [ABSTRACT FROM AUTHOR]

The lateral distributions of depth-averaged velocity in open compound channels with emerged and submerged vegetated floodplains were analyzed based on the analytical solution of the depth-integrated Reynolds-Averaged Navier-Stokes equation with a term to account for the effects of vegetation. The three cases considered for open channels were two-stage rectangular channel with emerged vegetated floodplain, rectangular channel with submerged vegetated corner, and two-stage rectangular channel with submerged vegetated floodplain, respectively. To predict the depth-averaged velocity with submerged vegetated floodplains, we proposed a new method based on a two-layer approach where flow above and through the vegetation layer was described separately. Moreover, further experiments in the two-stage rectangular channel with submerged vegetated floodplain were carried out to verify the results. The analytical solutions of the cases indicated that the corresponding analytical depth-averaged velocity distributions agree well with the simulated and experimental prediction. The analytical solutions of the cases with theoretical foundation and without programming calculation were reasonable and applicable, which were more convenient than numerical simulations. The analytical solutions provided a way for future researches to solve the problems of submerged vegetation and discontinuous phenomenon of depth-averaged velocity at the stage point for compound channels. Understanding the hydraulics of flow in compound channels with vegetated floodplains is very important for supporting the management of fluvial processes. [ABSTRACT FROM AUTHOR]

The 2008 Wenchuan earthquake triggered more than 100 rock avalanches with volumes greater than 10 million cubic metres. The rock avalanche with the longest runout amongst these destructive landslides occurred in the Wenjia valley, Mianzhu, Sichuan, China. The landslide involved the failure of about 27.5 million cubic metres of sandstone from the source area. The displaced material travelled about 4,170 m with an elevation descent of about 1,360 m, equivalent to a fahrböschung of 16.9° and covered an area of 1.5 million square metres, with the final deposited volume of approximately 49 million cubic metres. The catastrophic event destroyed the village of Yanjing, killed 48 people and buried some houses at the mouth of the Wenjia valley. On the basis of a detailed field investigation, we introduce basic characteristics of the rock avalanche and find that the rock avalanche resulted in two run-ups and a superelevation along the runout path, and downslope enlargement due to the entrainment of path materials. A numerical model (DAN3D) is used to simulate the post-failure behaviour of the rock avalanche. By means of trial and error, a combination of the frictional model and Voellmy model is found to provide the best performance in simulating this rock avalanche. The simulation results reveal that the rock avalanche had a duration of about 240 s and an average velocity of 17.4 m/s. [ABSTRACT FROM AUTHOR]

Since 1979, the Pearl River Delta (PRD) of China has experienced rapid socioeconomic development along with a fast expansion of construction area. Affected by both natural and human factors, a complex interdependency is found among the regional changes in construction area, GDP and population. A quantitative analysis of the four phases of the regional land use data extracted from remote sensing images and socioeconomic statistics spanning 1979 to 2009 demonstrates that the proportion of construction area in the PRD increased from 0.5% in 1979 to 10.8% in 2009, accompanied with a rapid loss of agricultural land. An increase of one million residents was associated with an increase of GDP of approximately 32 billion yuan before 2000 and approximately 162 billion yuan after 2000. Because the expansion of construction area has approached the limits of land resource in some cities of the PRD, a power function is found more suitable than a linear one in describing the relationship between GDP and construction area. Consequently, the Logistic model is shown to provide more accurate predictions of population growth than the Malthus model, particularly in some cities where a very large proportion of land resource has been urbanized, such as Shenzhen and Dongguan. [ABSTRACT FROM AUTHOR]

Caspases have been demonstrated to possess important functions in apoptosis and immune system in vertebrate. But there is less information reported on the oyster larval development. In the present work, two full-length molluscan caspase genes, named Cacaspase- 2 and Cacaspase- 3, were characterized for the first time from Fujian oyster, Crassostrea angulata. Which respectively encode two predicted proteins both containing two caspase domains of p20 and p10 including the cysteine active site pentapeptide 'QACRG' and the histidine active site signature. Otherwise Cacaspase- 2 also contains a caspase recruitment domain. Homology and phylogenetic analysis showed that Cacaspase- 2 shared high similarity with initiator caspase- 2 groups, but Cacaspase- 3 clustered together with executioner caspase- 3 groups. Cacaspase- 2 and Cacaspase- 3 mRNA were both highly expressed in gills and labial palp and were significantly expressed highly in larvae during settlement and metamorphosis. Through the whole mount in situ hybridization, the location of Cacaspase- 2 is in the foot of the oyster larvae and the location of Cacaspase- 3 is in both the foot and velum tissues. These results implied that Cacaspase- 2 and Cacaspase- 3 genes play a key role in the loss of foot and Cacaspase- 3 gene has an important function in the loss of velum during larvae metamorphosis in C. angulata. [ABSTRACT FROM AUTHOR]

Cyber-physical systems integrate information and communication technology with the physical elements of a system, mainly for monitoring and controlling purposes. The conversion of traditional power grid into a smart grid, a fundamental example of a cyber-physical system, raises a number of issues that require novel methods and applications. One of the important issues in this context is the verification of certain quantitative properties of the system. In this paper, we consider a specific Chinese smart grid implementation as a case study and address the verification problem for performance and energy consumption. We employ stochastic model checking approach and present our modelling and analysis study using PRISM model checker. [ABSTRACT FROM AUTHOR]

Double- and triple-cropping in a year have played a very important role in meeting the rising need for food in China. However, the intensified agricultural practices have significantly altered biogeochemical cycles and soil quality. Understanding and mapping cropping intensity in China's agricultural systems are therefore necessary to better estimate carbon, nitrogen and water fluxes within agro-ecosystems on the national scale. In this study, we investigated the spatial pattern of crop calendar and multiple cropping rotations in China using phenological records from 394 agro-meteorological stations (AMSs) across China. The results from the analysis of in situ field observations were used to develop a new algorithm that identifies the spatial distribution of multiple cropping in China from moderate resolution imaging spectroradiometer (MODIS) time series data with a 500 m spatial resolution and an 8-day temporal resolution. According to the MODIS-derived multiple cropping distribution in 2002, the proportion of cropland cultivated with multiple crops reached 34% in China. Double-cropping accounted for approximately 94.6% and triple-cropping for 5.4%. The results demonstrat that MODIS EVI (Enhanced Vegetation Index) time series data have the capability and potential to delineate the dynamics of double- and triple-cropping practices. The resultant multiple cropping map could be used to evaluate the impacts of agricultural intensification on biogeochemical cycles. [ABSTRACT FROM AUTHOR]

GABA receptors (GABARs) mediate the majority of fast synaptic inhibition. Trafficking regulation and protein-protein interactions that maintain the appropriate number of GABARs at the cell surface are considered to be important mechanisms for controlling the strength of synaptic inhibition. Here, we report that BIG1, a brefeldin A (BFA)-inhibited guanine nucleotide-exchange factor (GEF) which has a known role in vesicle trafficking, is a new binding partner of GABARs. Treatment of neurons with BFA, an uncompetitive inhibitor of BIG1 GEF activity, or depletion of BIG1 by small RNA interference (siRNA) significantly decreased GABARs at the neuronal surface and suppressed GABA-gated influx of chloride ions. Over-expression of HA-tagged BIG1-E793K, a dominant-negative mutant, also significantly decreased GABARs at the neuronal surface, but had no effect on the total amount of GABARs. Inhibition of GABAR endocytosis by muscimol increased both GABARs and BIG1 at the neuronal surface in a time-dependent fashion, and this increase could be abolished by bicuculline. Finally, depletion of BIG1 by siRNA inhibited the muscimol-stimulated increase of GABARs. Those data suggest an important function of BIG1 in trafficking of GABARs to the cell surface through its GEF activity. Thus, we identify an important role of BIG1 in modulating GABA-gated Cl influx through the regulation of cell surface expression of GABARs. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotubes (SWNT) possess high-near-infrared absorption coefficient, large surface area, and have great potential in drug delivery. In this study, we obtained ultrashort oxidized SWNT (OSWNT) using mixed acid oxidation method. Then, docetaxel (DTX) and folic acid (FA) are conjugated with OSWNT via π- π accumulation and amide linkage, respectively. A targeting and photothermal sensitive drug delivery system FA-DTX-OSWNT-SLN was prepared following a microemulsion technique. The size and zeta potential of FA-DTX-OSWNT-SLN were 182.8 ± 2.8 nm and −34.59 ± 1.50 mV, respectively. TEM images indicated that FA-DTX-OSWNT-SLN was spherical and much darker than general solid lipid nanoparticles (SLN). Furthermore, OSWNT may wind round, insert into or be encapsulated into the nanocarriers. Compared with free DTX, FA-DTX-OSWNT-SLN could efficiently cross cell membranes and afford higher antitumor efficacy in MCF-7 cells in vitro. Meanwhile, the combination of near-infrared laser (NIR) irradiation at 808 nm significantly enhanced cell inhibition. In conclusion, FA-DTX-OSWNT-SLN drug delivery system in combination with 808 nm NIR laser irradiation may be promising for targeting and photothermal cancer therapy with multiple mechanisms in future. [ABSTRACT FROM AUTHOR]

This study aimed to compare the safety and thoroughness of preoperative versus intraoperative injections of nanocarbon tracers into the thyroid gland in thyroid cancer operations. We conducted a retrospective analysis of 182 patients with thyroid cancer from January 1, 2019, to June 1, 2021. According to the timing of the injection of the nanocarbon tracer, they were divided into a preoperative injection group and an intraoperative injection group. The operation time, intraoperative blood loss, total postoperative drainage, average hospital stay, serum calcium (Ca2+) and parathyroid hormone (PTH) levels at different times, number of lymph nodes dissected from the central region, number of lymph nodes with metastatic cancer in the dissected central region, and incidences of inadvertent parathyroid removal, hoarseness, and bleeding after surgery were all compared between the two groups. The operation time of the preoperative injection group was shorter than that of the intraoperative injection group (P = 0.004). The levels of Ca2+ and PTH in the preoperative injection group were higher than those in the intraoperative injection group 24 h after the operation (P < 0.05). The number of central region lymph nodes detected in the preoperative injection group was significantly higher than that in the intraoperative injection group (P < 0.05). However, the difference in the number of lymph nodes with metastatic cancer in the dissected central region between the two groups was not statistically significant (P > 0.05). The incidences of inadvertent parathyroid removal were lower in the preoperative injection group than in the intraoperative injection group (P < 0.05). The differences between the two groups in complications after the operation were not statistically significant (P > 0.05). Compared to the intraoperative injection of nanocarbon tracers, the preoperative injection of nanocarbon tracers can enhance the safety of thyroid cancer surgery. Meanwhile, preoperative injection of nanocarbon tracers can also increase the accuracy and thoroughness of the operation. [ABSTRACT FROM AUTHOR]

As they are products of glacier movement, the water body composition and water quality attributes of glacial lakes have distinct characteristics compared with inland lakes. Although satellite remote sensing provides an effective approach to monitor water quality, lack of in-situ measurement data on the status and environment surrounding glacial lakes presents a major constraint in relating satellite data to water quality indicators. This study presents findings of a preliminary investigation into water quality attributes of 3 glacial lakes in the Mount Qomolangma region. Suspended particulate matter (SPM), light absorption attributes of phytoplankton, nonalgal particles (NAP), and colored dissolved organic matter (CDOM) were measured. The suspended substance concentration varies markedly from 0-320 mg/L. This is considered to reflect differing stages of lake development. The chlorophyll concentration is much lower than that found for inland lakes, as landscapes that surround these high altitude lakes have almost no vegetation growth. The phytoplankton and CDOM concentration depend on long-term stability of lake slopes. Given the lack of exogenous and endogenous inputs in the Qomolangma region, CDOM in glacial lakes is significantly lower than in inland lakes. These preliminary findings could support efforts to appraise estimates of water quality parameters using remotely sensed images. [ABSTRACT FROM AUTHOR]

The spatial distribution of valley setting (laterally-unconfined, partly-confined, or confined) and fluvial morphology in the source region of the Yangtze and Yellow Rivers is contrasted and analyzed. The source region of the Yangtze River is divided into 3 broad sections (I, II and III) based on valley setting and channel gradient, with the upstream and downstream sections being characterized by confined (some reaches partly-confined) valleys, while the middle section is characterized with wide and shallow, laterally-unconfined valleys. Gorges are prominent in sections I and III, while braided channel patterns dominate section II. By contrast, the source region of the Yellow River is divided into 5 broad sections (sections I-V) based on valley characteristics and channel gradient. Sections I, II and IV are alluvial reaches with mainly laterally-unconfined (some short reaches partly-confined) valleys. Sections III and V are mainly confined or partly-confined. Greater morphological diversity is evident in the source region of the Yellow River relative to the upper Yangtze River. This includes braided, anabranching, anastomosing, meandering and straight alluvial patterns, with gorges in confined reaches. The macro-relief (elevation, gradient, aspect, valley alignment and confinement) of the region, linked directly to tectonic movement of the Qinghai-Tibet Plateau, tied to climatic, hydrologic and biotic considerations, are primary controls upon the patterns of river diversity in the region. [ABSTRACT FROM AUTHOR]

There is growing concern over the effects of climate change on glacier melt and hydrology. In this article, we used two natural small-scale basins, Tuotuo River and Buqu River in the source region of the Yangtze River, China, to show the impacts of glacier melt on stream flow. Changes in the extent of glaciers and ice volume in 1970, 1992 and 2009 are evaluated using remote sensing images. Changes to the glacier surface area over the same time interval are estimated through the delineation of glacier outlines and positions using Landsat TM/ETM+ imagery. By 2009, the glacier surface area had decreased by 20.83% and 34.81% of the 1970 values in Tuotuo River and Baqu River basins respectively. The total meltwater supply in each basin is estimated to be 2.56×10 m/yr and 1.24×10 m/yr respectively. Mass balance calculations show that glaciers in the study area suffered a constant mass loss of snow and ice, accumulatively approximately −24 m over the past 40 years. The annual and summer stream flow tended to increase in Tuotuo River basin from 1970 to 2009 while a negative trend of change was shown in Buqu River basin during 1970-1986. Glaciers became shorter, narrower and thinner under the effect of atmospheric warming. Streamflow increase has been recorded at Tuotuo River station in response to increased glacier and permafrost melt. However, streamflow decrease has been recorded at Yanshiping station on Buqu River, where glacier melt has lagged behind atmospheric warming. These results show a close but variable linkage among climate change, glacier melting and water resources in the source region of the Yangtze River. [ABSTRACT FROM AUTHOR]

The mechanism of iron release from ferritin in vivo is still unclear even though it represents a key step of the metabolism of iron in vivo. Here, both interaction intensity and binding stability between epigallocatechin gallate (EGCG) from tea and liver ferritin of Dasyatis akajei (DALF) were investigated using UV-visible, fluorescence and circular dichroism (CD) spectrometry, respectively. The results indicated that EGCG could reduce the iron within the ferritin shell directly in the absence of chemical reducers such as NaSO, but this process was strictly pH-dependent, and the rate of iron release is faster at low pH than at high pH. The kinetic study of iron release showed that this process fitted the law of zero order reaction, which differed from that of first order reaction by various chemical reducers such as Vitamin C. In addition, Both fluorescence and CD spectrometry were further used to study the reduction mechanism of iron release in vitro, showing that there was a slight conformation change of the ferritin shell during EGCG reduction because of a complex formation of DALF-EGCG. It appears that chemical reducers with large molecular sizes reduce the iron across the protein shell by the way of an electron transfer pathway (ETP). A novel pathway for iron release from DALF with EGCG reduction is suggested to explain for a reductive route of iron metabolism by biological reducers in vivo. [ABSTRACT FROM AUTHOR]

This study compared precipitation, mean air temperature (MAT) and mean sea level pressure (MSLP) from two widely used reanalysis datasets (ERA-40 and NCEP) with those from observed stations across eastern China. The evaluation was based on a comparison of both temporal and spatial variability and included several assessment criteria such as the mean values, normalized root mean square error, Mann-Kendall test, empirical orthogonal functions (EOFs) and probability density functions. The results showed that both the ERA-40 and NCEP datasets could capture temporal and spatial variability of the observed precipitation, MAT and MSLP over eastern China. The results showed that the two reanalysis datasets performed better for MAT and MSLP than for precipitation. Overall, the two reanalysis datasets revealed reasonable agreement with observations according to the evaluation. ERA-40 was better at capturing the temporal and spatial distributions for these three variables than NCEP, especially for MAT and MSLP. NCEP tended to overestimate the annual precipitation for both mean and extreme values, while ERA-40 tended to underestimate it, particularly for extreme values. The two reanalysis datasets performed better in the east and northeast regions of the study area than in other regions for capturing the temporal variability of MAT and MSLP. ERA-40 was poor at capturing the temporal variability of precipitation in northeastern China. According to the trend analysis, the two reanalysis datasets showed lower trends for MAT and precipitation and higher trends for MSLP. Both ERA-40 and NCEP had larger explained variances for the first two EOFs than the observed precipitation. This implies that both reanalysis datasets tend to simulate a more uniform spatial distribution for precipitation in the study area. [ABSTRACT FROM AUTHOR]

The shrinking and drying up of wetlands in arid and semiarid areas of China have been widely observed in the recent years, but there has been no consensus on whether the aggravation is caused by human activities or by global climate warming. For a better understanding of the cause, this study investigates the dynamic changes of Baiyangdian Lake wetland over the last 40 years. It is shown that since the 1980s, Baiyangdian Lake has suffered from an insufficient water input and shrunk considerably. By using SPSS11.0, this study undertakes a detailed analysis on the significance of the effects of the possible driving factors for the degradation. It is identified that the North China Plain has been warming up significantly in recent years, which causes a significant reduction in the precipitation and inflow to the lake. Although human disturbances such as the irrigation and storage of water in reservoirs do not play a decisive role, they accelerate the degradation and their effects should be minimized. [ABSTRACT FROM AUTHOR]