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Obtaining and analyzing the specific inherent optical properties (SIOPs) of water bodies is necessary for bio-optical model development and remote sensing-based water quality retrievals and, further, for related ecological studies of aquatic ecosystems. This study aimed to measure and analyze the specific absorption and backscattering coefficients of the main water constituents in Poyang Lake, China. The specific absorption and/or backscattering coefficients of the main water constituents at 85 sampling sites (47 in 2010 and 38 in 2011) were measured and analyzed as follows: (1) the concentrations of chlorophyll a (C(CHL)), suspended particulate matter (C(SPM)) (including suspended particulate inorganic matter (C(SPIM)) and suspended particulate organic matter (C(SPOM))), and the absorption coefficients of total particulate (a(p)), phytoplankton (a(ph)), and non-pigment particulate (a(d)) were measured in the laboratory; (2) the total backscattering coefficients at six wavelengths of 420, 442, 470, 510, 590, and 700 nm, including the contribution of pure water, were measured in the field with a HydroScat-6 backscattering sensor, and the backscattering coefficients without the contribution of pure water (b(b)) were then derived by subtracting the backscattering coefficients of pure water from the total backscattering coefficients; (3) the specific absorption coefficients of total particulate (a*(p)), phytoplankton (a(ph)*), and non-pigment particulate (a*(d)) were calculated by dividing a(p), a(ph), and ad by C(SPM), C(CHL), and C(SPIM), respectively, while the specific backscattering coefficients of total suspended particulate matter (b*(b)) were calculated by dividing b(b) by CSPM; and (4) the a(ph)*, a*(d), a*(p) and b*(b) of the remaining samples (46 in 2010 and 36 in 2011) were visualized and analyzed, and their relations to CCHL, CSPIM or CSPM were studied, respectively. The main results are summarized as follows: (1) the a(ph)* values at 440 nm were 0.0367-0.7203 m(2) mg(-1) with a mean of 0.1623 ± 0.1426 m(2) mg(-1) in 2010 and 0.0319-0.7735 m(2) mg(-1) with a mean of 0.3145 ± 0.1961 m(2) mg(-1) in 2011; there existed significant, negative, and moderate correlations between a(ph)* and C(CHL) at 400-700 nm in 2010 and 2011 (p<0.05); (2) The a*(d) values at 440 nm were 0.0672-0.2043 m(2) g(-1) with a mean of 0.1022 ± 0.0326 m(2) g-1) in 2010 and 0.0559-0.1347 m(2) g(-1) with a mean of 0.0953 ± 0.0196 m(2) g(-1) in 2011; there existed negative correlations between a*(d) and C(SPIM), while the correlations showed overall decreasing and increasing trends before and after around 575 nm with increasing wavelengths, respectively; (3) The a*(p) values at 440 nm were 0.0690-0.1929 m(2) g(-1) with a mean of 0.1036 ± 0.0298 m(2) g(-1) in 2010 and 0.0571-0.1321 m(2) g(-1) with a mean of 0.1014 ± 0.0191 m(2) g(-1) in 2011, and the negative correlations between a*(p) and C(SPM) were found in both years; (4) The b*(b) at the six wavelengths generally decreased with increasing wavelengths, while the b*(b) values at 420 nm were lower than those at 442 nm for some samples; the correlation between b*(b) and C(SPM) increased with increasing wavelength. Such results can only represent the SIOPs during the sampling time periods, and more measurements and analyses considering different seasons need to be carried out in the future to comprehensively understand the SIOPs of Poyang Lake.

The middle and lower reaches of the Yangtze River basin have the most representative and largest concentration of freshwater lakes in China. However, the size and number of these lakes have changed considerably over the past century due to the natural and anthropogenic impact. The lakes, larger than 10 km(2) in size, were chosen from relief maps and remotely sensed images in 1875, 1950, 1970, 1990, 2000, and 2008 to study the dynamics of lakes in the middle and lower reaches of the Yangtze River basin and to examine the causes and consequences of these changes. Results indicated that there was a dramatic reduction in lake areas, which decreased by 7,841.2 km(2) (42.64 %) during the study period (1875-2008), and the number of lakes in this region changed moderately. Meanwhile, a large number of lakes in the middle and lower reaches of the Yangtze River basin were directly converted into paddy fields, ponds, building lands, or other land-use types over the study period. Therefore, all kinds of lake reclamation should be identified as the major driving factors for the loss of lake in this region. Furthermore, flooding, soil erosion, and sedimentation were also the main factors which triggered lake changes in different periods. Some wetland conservation and restoration projects have been implemented since the 1970s, but they have not reversed the lake degradation. These findings were of great importance to managers involved in making policy for the conservation of lake ecosystems and the utilization of lake resources.

Summary: Cognitive and depressive disorders are common in elderly Chinese and are becoming an increasingly important public health problem, partly because of the rapid aging of the population. To help address this issue China's national government has funded a major study to establish national standards for the early identification, evaluation and treatment of common psychological disorders in the elderly. The present paper describes the overall methodology of this study. Fifteen centers in eight provinces will recruit representative samples of subjects aged 60 and over, collect a detailed history, conduct a physical and neurological examination, administer a comprehensive battery of psychological tests, and carry out a diagnostic exam using the Structured Clinical Interview for DSM-IV (SCID). These subjects will participate in follow-up evaluations one year and three years after the initial evaluation. Subsamples of subjects with mild cognitive impairment (MCI) and subclinical depression will be enrolled in randomized controlled trials of a cognitive training program (for MCI) or group cognitive behavioral therapy (for subclinical depression). The results of the study will be used to estimate the prevalence of cognitive and affective disorders in the elderly, to develop a standard screening procedure for these conditions that can be promulgated nationally, and to promote the use of specific interventions that can prevent the development of dementia in persons with MCI and the development of depressive episodes in elderly individuals with subclinical depression.

Distributed video coding (DVC) is rapidly increasing in popularity by the way of shifting the complexity from encoder to decoder, whereas no compression performance degrades, at least in theory. In contrast with conventional video codecs, the inter-frame correlation in DVC is explored at decoder based on the received syndromes of Wyner-Ziv (WZ) frame and side information (SI) frame generated from other frames available only at decoder. However, the ultimate decoding performances of DVC are based on the assumption that the perfect knowledge of correlation statistic between WZ and SI frames should be available at decoder. Therefore, the ability of obtaining a good statistical correlation estimate is becoming increasingly important in practical DVC implementations. Generally, the existing correlation estimation methods in DVC can be classified into two main types: pre-estimation where estimation starts before decoding and on-the-fly (OTF) estimation where estimation can be refined iteratively during decoding. As potential changes between frames might be unpredictable or dynamical, OTF estimation methods usually outperforms pre-estimation techniques with the cost of increased decoding complexity (e.g., sampling methods). In this paper, we propose a low complexity adaptive DVC scheme using expectation propagation (EP), where correlation estimation is performed OTF as it is carried out jointly with decoding of the factor graph-based DVC code. Among different approximate inference methods, EP generally offers better tradeoff between accuracy and complexity. Experimental results show that our proposed scheme outperforms the benchmark state-of-the-art DISCOVER codec and other cases without correlation tracking, and achieves comparable decoding performance but with significantly low complexity comparing with sampling method.

Human activities produced great impacts on wetlands worldwide. Taking Jiangsu Province, China, as a representative wetland region subject to extensive human activities, the aim of this study is to understand the conversion trajectory and spatial differentiation in wetland change from a multi-scale perspective. Based on multi-temporal Landsat images, it was found that the natural wetlands decreased by 11.2% from 1990 to 2006 in Jiangsu Province. Transition matrices showed that the conversion of natural wetlands to human-made wetlands (mostly aquaculture ponds) was the major form of natural wetland reduction, accounting for over 60% of the reduction. Percentage reduction and area reduc tion of natural wetlands were respectively quantified within different wetland cover zones using a moving window analysis. Average percentage reduction showed a decreasing tendency with increasing wetland cover. The high-cover and mid-cover zone presented the largest area reduction at the scales of 1-2 km and 4-8 km, respectively. Local hotspots of natural wetland reduction were mapped using the equal-interval and quantile classification schemes. The hotspots were mostly concentrated in the Lixiahe marshes and the coastal wetland areas. For the area reduction hotspots, the quantile classification presented larger area and more patches than the equal-interval classification; while an opposite result was shown for the percentage reduction hotspots. With respect to the discontinuous distribution of the natural wetlands, area reduction could be more appropriate to represent reduction hotspots than percentage reduction in the study area. These findings could have useful implications to wetland conservation.

The actions and mechanisms of taurine on vascular contractions have been studied in the isolated porcine coronary artery. Taurine depressed histamine-, serotonin-, KCl- and CaCl(2)-induced contractions in a concentration-dependent manner, with maximal contractions being depressed by 43.4%, 46.2%, 33.3% and 43.3%, respectively. Taurine relaxed arterial rings that were precontracted by either 30mM KCl or 0.3 muM U46619, a thromboxane A(2) analog, in a concentration-dependent manner, and the maximal relaxations were 39.4% and 38.7%, respectively. The vasorelaxations were nearly abolished by pretreatment with either the inward rectifier K(+) channel (K(IR)) inhibitor, BaCl(2), or the ATP sensitive K(+) channel (K(ATP)) inhibitor, glibenclamide, and were attenuated by the Ca(2+)-activated K(+) channel (K(Ca)) inhibitor tetraethylammonium. Denudation of the endothelium, and treatment with the nitric oxide synthase inhibitor, L-NAME, the cyclooxygenase inhibitor, indomethacin, or the voltage gated K(+) channel (K(V)) inhibitor 4-aminopyridine did not affect the relaxation. The present results show that taurine antagonizes and relaxes the contractions of the porcine coronary artery, and suggest that the activation of K(IR), K(ATP) and K(Ca) may be involved in taurine-induced relaxation of the porcine coronary artery.

alpha-FeOOH nanorods with diameters of 15-25 nm and lengths up to 170-300 nm were synthesized in high yield via a facile and template-free hydrothermal method at low temperature. After calcining the as-synthesized alpha-FeOOH at 250 degrees C for 2 h, we could obtain alpha-Fe2O3 nanorods. Interestingly, the as-obtained alpha-Fe2O3 nanorods exhibited weakly ferromagnetic characteristics at low temperature and superparamagnetic property at room temperature, which is different from the behavior of the corresponding bulk material.

With the support of RS and GIS, and using a series of indices in characterizing the dynamics of land use, this paper studied the temporal-spatial characteristics of land use in Xinjian County, Jiangxi Province, between 1991 and 2000. The results indicated that among single land use types, the area for construction changed mostly. The annual change speed of comprehensive land dynamic index between 1991 and 1995 was 0.5 times higher than that between 1996 and 2000, and the utilization grade in 1991, 1996 and 2000 was 243.7, 44.1 and 244.9, respectively, being a little higher than the national average grade. The land inflow and outflow in 1996 to approximately 2000 was lower than that in 1991 to approximately 1995, and the land use change was from bilateral dynamics to unilateral unbalanced dynamics.