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As the world's largest electricity-consuming country, China faces the challenge of energy conservation and environmental pollution. Therefore, it is imperative that China takes decisive action to address these issues. Based on the panel data of 30 provinces (cities, districts) in China from 2011 to 2020, we use the entropy method to measure the air pollution index in different provinces, construct two fixed effects models, panel quantile model, and spatial Durbin model to empirically analyze the impact of electricity consumption on air pollution in China's provincial regions. The experimental results show that: (1) Electricity consumption has a significant positive impact on the provincial air pollution index in China and the higher the index is, the more serious the air pollution is. When the electricity consumption increases 1%, the air pollution index will increase of by 0.0649% as accompanied. (2) Through comparison of different times, we found that the degree of increase in air pollution index caused by electricity consumption would be reduced due to the improvement of environmental protection efforts. From the perspective of different geographical locations, the electricity consumption in the southeast side of the "Hu Line" has exacerbated the impact on air pollution index. (3) According to the panel quantile regression results, the marginal effect of electricity consumption on air pollution is positive. With the increase of quantiles, the impact of electricity consumption on air pollution is increasing. (4) Spatial effect analysis shows that electricity consumption has a significant positive spatial spillover effect on air pollution index. The increase in electricity consumption not only increases the air pollution index in the local region, but also leads to an increase in the air pollution index in surrounding areas. These findings contribute to the governance of air pollution and the promotion of sustainable economic, environmental and energy development. [ABSTRACT FROM AUTHOR]

Tobacco smoke (TS) is the leading cause for lung cancer (LC), and female smokers are at a greater risk for LC. Yet, the underlying causes are unknown. We performed whole genome scans in TS exposed wild type and histologically characterized tumor lesions of cRaf transgenic mice. We constructed miRNA-gene and transcription factor-miRNA/gene regulatory networks and determined sex-specific gene regulations by evaluating hormone receptor activities. We validated the findings from TS exposed cRaf mice in a large cohort of smoking and never-smoking LC patients. When compared to males, TS prompted a sevenfold increase in tumor multiplicity in cRaf females. Genome-wide scans of tumor lesions identified 161 and 53 genes and miRNAs, which code for EGFR/MAPK signaling, cell proliferation, oncomirs and oncogenes, and 50% of DEGs code for immune response and tumor evasion. Outstandingly, in transgenic males, TS elicited upregulation of 20 tumor suppressors, some of which are the targets of the androgen and estrogen receptor. Conversely, in females, 18 tumor suppressors were downregulated, and five were specifically repressed by the estrogen receptor. We found TS to perturb the circadian clock in a sex-specific manner and identified a female-specific regulatory loop that consisted of the estrogen receptor, miR-22-3p and circadian genes to support LC growth. Finally, we confirmed sex-dependent tumor promoting effects of TS in a large cohort of LC patients. Our study highlights the sex-dependent genomic responses to TS and the interplay of circadian clock genes and hormone receptors in the regulation of oncogenes and oncomirs in LC growth. [ABSTRACT FROM AUTHOR]

Improving green innovation efficiency (GIE) is the key to achieve high-quality economic development in China, and the introduction of foreign direct investment (FDI) has become an important path choice to promote the GIE. Based on the data of 30 provinces in China, this paper explores the linear and nonlinear effects of FDI on GIE from both quantity and quality perspectives, and further analyzes the mediating role of environmental regulation level. The results show that: (1) From 2011 to 2020, the GIE of all provinces in China generally shows an upward trend. (2) The quantity and quality of FDI have a significant positive impact on the improvement of GIE in China's provinces, and this impact has regional heterogeneity. (3) The quantity and quality of FDI can promote the improvement of GIE in China through the level of environmental regulation (ER). (4) With the level of knowledge accumulation and GIE as the threshold variables, the quantity and quality of FDI have a single threshold effect on the GIE of China's provinces. The conclusions of this study provide some policy implications for local governments to make full use of FDI to perform green innovation activities. [ABSTRACT FROM AUTHOR]

Understanding the complex patterns of latitudinal diversity gradients (LDGs) in deep time has been hampered by the absence of long-term records of LDGs through multiple climatic changes. We used records of marine invertebrate fossils to generate LDGs in each age bin from the Carboniferous icehouse to the Triassic greenhouse climates. We evaluated LDGs by subsampling, calculated evolutionary rates for different latitudinal zones, and assessed the modularity of the fossil data within latitudinal zones using the Louvain algorithm. Our results suggest that the LDG peaks may be shaped by multiple factors rather than alternating icehouse and greenhouse climates, although icehouse climates usually restrict diversity at high latitudes. In nearly all clades, peak diversity shifted northward during the late Carboniferous and early Permian, reflecting the northward drift of plates and increased habitat area. Changes in the steepness of the LDG was most pronounced at low latitudes and during biotic crises and recovery, while icehouse to greenhouse transitions created more deviation at high latitudes. Our results show a strong historical influence from previous LDG patterns in LDG dynamics, but one that was interrupted by upheavals in composition after dramatic environmental changes. [ABSTRACT FROM AUTHOR]

Background: The aim of this study is to investigate role of Visfatin, one of the pro-inflammatory adipokines, in sepsis-induced intestinal injury and to clarify the potential mechanism. Methods: C57BL/6 mice underwent cecal ligation and puncture (CLP) surgery to establish sepsis model in vivo. Intestinal epithelial cells were stimulated with LPS to mimic sepsis-induced intestinal injury in vitro. FK866 (the inhibitor of Visfatin) with or without XMU-MP-1 (the inhibitor of Hippo signaling) was applied for treatment. The expression levels of Visfatin, NF-κB and Hippo signaling pathways-related proteins were detected by western blot or immunohistochemistry. The intestinal cell apoptosis and intestinal injury were investigated by TUNEL staining and H&E staining, respectively. ELISA was used to determine the production of inflammatory cytokines. Results: The expression of Visfatin increased in CLP mice. FK866 reduced intestinal pathological injury, inflammatory cytokines production, and intestinal cell apoptosis in sepsis mice. Meanwhile, FK866 affected NF-κB and Hippo signaling pathways. Additionally, the effects of FK866 on inflammatory response, apoptosis, Hippo signaling and NF-κB signaling were partly abolished by XMU-MP-1, the inhibitor of Hippo signaling. In vitro experiments also revealed that FK866 exhibited a protective role against LPS-induced inflammatory response and apoptosis in intestinal cells, as well as regulating NF-κB and Hippo signaling, whereas addition of XMU-MP-1 weakened the protective effects of FK866. Conclusion: In short, this study demonstrated that inhibition of Visfatin might alleviate sepsis-induced intestinal injury through Hippo signaling pathway, supporting a further research on Visfatin as a therapeutic target. [ABSTRACT FROM AUTHOR]

As China's strategic support belt, the green development of industry in the Yangtze River Economic Zone is of great significance to promote the construction of China's ecological civilization, build a modern industrial system and accelerate high-quality economic development. The study of green total factor productivity of industry in the Yangtze River Economic Zone has important theoretical and practical value for exploring the green development path of China's industry. This Paper takes the Yangtze River Economic Zone, a key strategic region in China, as the research object, selects the input and output data of industrial production from 2006 to 2018, based on DEA model. To construct an MML index considering expected and unexpected output, and to quantitatively analyze the changes of industrial GTFP in the Yangtze River Economic Zone. The results show that: (1) During the sample period, the industrial green total factor productivity in the Yangtze River Economic Zone shows the spatial characteristics of differential growth and the temporal characteristics of volatile growth. It shows the fluctuation characteristics of "N" shape. (2) According to the order of "upper, middle, and lower" reaches, the spatial pattern of industrial green total factor productivity is characterized by "lower ladder". But the difference between the upper and middle reaches is small. (3) Cities with higher green total factor productivity and lower green total factor productivity each form the characteristics of "club convergence" of spatial agglomeration. (4) Technological efficiency and technological progress efficiency have heterogeneous effects on different river basins in the upper, middle, and lower reaches, and technological progress efficiency is conducive to promoting the evolution of green total factor productivity to a high level. According to the above empirical results, this paper finally puts forward the policy recommendations to improve the industrial green total factor productivity of the Yangtze River Economic Zone and the policy recommendations to reduce the industrial differences between the Yangtze River Economic Zone. [ABSTRACT FROM AUTHOR]

The pig industry occupies an extremely significant position in agriculture. The input cost, output income and the amount of pollution emitted by pig farming of different scales are unequal. It is of great practical importance to reduce pollutant emission by improving efficiency for the development of hog breeding industry in China. With the addition of undesirable output, this paper uses the Slack Based Measure- Metafrontier Malmquist Luenberger index model considering scale heterogeneity to explore the evolution characteristics of China's green total factor productivity of pig breeding (GTPB) based on the data of China's 17 major pig producing provinces from 2004 to 2018. The results indicate that: (1) From 2004 to 2018, China's large-scale GTPB is the highest, the medium-sized is the second, and the small-scale is the lowest. (2) In terms of regional distribution, China's GTPB in western region is the highest, in eastern region is the second, and in central region is the lowest. (3) China's GTPB shows efficiency growth and technological decline from 2004 to 2018. The pig breeding industry is generally fragile, which is greatly affected by emergencies. (4)The TGR of large-scale pig breeding is closest to 1, followed by middle-scale, and finally small-scale. According to the above empirical results, this text puts forward some policy suggestions to improve GTPB and environmental protection recommendations of hog breeding. [ABSTRACT FROM AUTHOR]

In people's daily life, egg is one of the main animal protein foods, which will produce different emissions on its breeding procedure. Therefore, in order to promote the development of China's layer industry, it is necessary to reduce pollutant emissions by improving efficiency. This paper uses Minimum distance to weak efficient frontier-Metafrontier Malmquist Luenberger (MinDW-MML) index model, by considering environmental factors and scale heterogeneity, to explore the evolution characteristics of laying hens breeding green total factor productivity (LHG) in China based on the data of 24 major laying provinces (municipalities) from 2004 to 2018. The results show that: (1) From 2004 to 2018, medium-scale LHG in China is the highest, the small-scale is the second, and the large-scale is the lowest. In the light of regional distribution, the western region is the highest, followed by the central region, and the eastern region is the lowest. (2) From 2004 to 2018, the overall China's LHG showed a positive growth, and the decomposition indicators were characterized by decreased efficiency and technological progress. In general, the layer industry is vulnerable and easily affected by external factors. (3) Results from common frontiers and group frontiers exist some differences. The LHG under the common frontier is lower than the LHG under the group frontier. Finally, according to the above empirical results, this paper puts forward policy suggestions to improve LHG and environmental protection suggestions for laying hens. [ABSTRACT FROM AUTHOR]

China's agricultural economy is developing rapidly, but the unbalanced regional development is still a key issue that needs to be discussed today. By studying the total factor productivity of green agriculture and its factors, this paper analyzes the regional differences in time and space changes between the eastern, central and western parts of China. In this paper, the total factor productivity of green agriculture is calculated and decomposed by Metafrontier Malmquist-Luenberger index based on directional distance function. The results are as follows: First, the total factor productivity level of green agriculture in China is increasing year by year, but the overall level is still at a low level and has greater volatility; Second, although the total factor productivity of green agriculture shows an upward trend, the three regions show a downward trend in turn, which has great differences; Third, there are obvious differences in technological efficiency, optimal production potential and technological gap between the eastern, central and western regions, and there are great differences in productivity among regions and provinces. Based on the results, this paper puts forward policy recommendations, according to the regional heterogeneity, from a number of angles to rely on the joint efforts of many parties to improve the level of total factor productivity of green agriculture. [ABSTRACT FROM AUTHOR]

Forestry plays an essential role in reducing CO2 emissions and promoting green and sustainable development. This paper estimates the CO2 emissions of 30 provinces in China from 2008 to 2017, and uses Global DEA-Malmquist to measure the total factor productivity of the forestry industry and its decomposition index. On this basis, by constructing a spatial econometric model, this paper aims to empirically study the impact of forestry industry's total factor productivity and its decomposition index on CO2 emissions, and further analyze its direct, indirect and total effects. The study finds that the impact of forestry industry's total factor productivity on CO2 emissions shows an "inverted U-shaped" curve and the inflection point is 0.9395. The spatial spillover effect of CO2 emissions is significantly negative. The increase of CO2 emissions in adjacent areas will provide a "negative case" for the region, so that the region can better address its own energy conservation and emission reduction goals. TFP of forestry industry also has positive spatial spillover effect. However, considering the particularity of forestry industry, this effect is not very significant. For other factors, such as foreign direct investment, urbanization level, industrial structure and technology market turnover will also significantly affect regional CO2 emissions. [ABSTRACT FROM AUTHOR]

Based on panel data from 210 prefecture-level cities in China from 2003 to 2021, this study employs the Time-Varying Differences-in-Differences (Time-Varying DID) approach to systematically examine the impact of smart city construction on pollution emissions and its underlying mechanisms. Additionally, the Propensity Score Matching–Differences-in-Differences method is employed for further validation. The research findings indicate that Smart City Construction (SCC) significantly reduces urban Volume of Sewage Discharge (VSD), sulfur dioxide emissions (SO2), and Emissions of Fumes and Dust (EFD), thereby mitigating pollution emissions (PE) and enhancing environmental quality. Mechanism analysis reveals that SCC achieves these effects through scale effects, structural effects, and technological effects. City heterogeneity analysis shows that provincial capital cities exhibit a stronger suppression effect on pollution emissions compared to non-provincial capital cities. Moreover, cities with lower levels of education attainment demonstrate a stronger ability to curb pollution emissions, while larger cities exhibit a more pronounced impact on mitigating pollution emissions. The marginal contributions of this study mainly consist of three aspects: Firstly, it enriches the literature on environmental impact factors by assessing, for the first time, the influence of SCC on PE. Secondly, a comprehensive approach is employed, integrating VSD, EFD, SO2 data, and economic and pollution data at the city level. Time-Varying DID is used to evaluate the policy effects of SCC. Finally, the study analyzes the impact mechanisms of SCC policy on environmental emissions from various perspectives. [ABSTRACT FROM AUTHOR]

Previous studies of the end-Permian mass extinction have established that it was geologically rapid, but condensed sections have made it difficult to establish the exact timing of the extinction relative to fluctuations in the ocean carbon cycle, oxygen levels, and temperature. Integrated high-precision U-Pb geochronology, biostratigraphy, and chemostratigraphy from a highly expanded section at Penglaitan, Guangxi, South China reveal a sudden end-Permian mass extinction that occurred at 251.939 ± 0.031 Ma, which is temporally coincident with the extinction recorded in Bed 25 of the Meishan section. Despite the significantly expanded nature of the section and extensive collecting of more than ten major marine fossil groups, there is no evidence of a decline of biotic diversity prior to the extinction interval and no Permiantype species survive the extinction at this location. Fossil range data suggest a nearly instantaneous extinction at the top of a narrow stratigraphic interval limited to 31 ± 31 k.y. The extinction was preceded by and/or accompanied by fluctuations in δ13Ccarb and δ13Corg of 2-3‰, and 3-5 °C in seawater temperature. A larger, more rapid seawater temperature rise of 6-8 °C immediately followed the extinction level at Penglaitan. The extinction is spatially associated with a thick unit of tuff and tuffaceous sandstones (Bed 141) indicating massive pyroclastic input. It is correlative with an ash layer (Bed 25) in the deeper water setting at Meishan, where some Permian-type organisms survived the extinction. Our study reveals that the survivability of Permian taxa after the major extinction pulse is variable and dependent upon the severity of environmental perturbation in different sedimentary settings. The sudden extinction may fit a scenario in which the onset of Siberian Traps and South China intensive volcanism ~420 k.y. before the extinction may have diminished the ecological resilience of communities and reduced ecological functions with little change in diversity. In such an environmentally stressed condition, a single environmental disturbance could trigger the sudden collapse of global ecosystems. [ABSTRACT FROM AUTHOR]

South China has become the most important area to establish a global stratigraphic framework of the Wuchiapingian Stage because complete Wuchiapingian sequences include the GSSPs for the base and top of the stage. As the markers of the Wuchiapingian GSSP, conodonts are the most important fossil group to establish the Wuchiapingian biostratigraphic framework. However, few documents have investigated in detail the conodont biostratigraphic succession through the entire Wuchiapingian Stage. Furthermore, the conodont taxonomy of several Wuchiapingian Clarkina species is still debated. Therefore, we here review all Wuchiapingian Clarkina species from South China and figure ontogenetic growth series from juvenile to adult individuals for each valid and important species in order to revise both Wuchiapingian conodont taxonomy and the biostratigraphic succession. Based on the Penglaitan, Dukou, and Nanjiang sections, seven conodont zones (Clarkina postbitteri postbitteri, C. dukouensis, C. asymmetrica, C. leveni, C. guangyuanensis, C. transcaucasica, and C. orientalis) are recognized. The Wuchiapingian Clarkina species lineage is also reviewed to confirm the conodont biostratigraphic framework. The Guadalupian-Lopingian boundary (GLB) interval represents a sequence boundary. The time framework of the pre-Lopingian extinction interval indicates that the beginning of the end-Guadalupian regression is in the upper part of the Jinogondolella postserrata Zone, and the beginning of the early Lopingian transgression is in the lower part of the Clarkina dukouensis Zone in South China. [ABSTRACT FROM AUTHOR]

In this paper, a 4-degree-of-freedom (DoF) anti-windup scheme is developed for anti-windup compensation of plants with actuator saturation. Instead of LMIs (Linear Matrix Inequalities) in modern anti-windup technique, sufficient stability conditions of the proposed anti-windup scheme are derived under the framework of IQC (Integral Quadratic Constraint). The sufficient conditions are formulated as a checking on the positive definiteness of the related transfer function at all frequencies for MIMO systems (or positive sign for SISO systems), which provides a fairly straightforward tuning rule in the frequency domain. Moreover, by virtue of the proposed scheme, control design for disturbance response is decoupled from set-point response. The proposed scheme can be implemented without system states or state estimates. Compared with IMC-based, low-order or dynamic compensation anti-windup schemes, numerical example shows remarkable performance improvement of the proposed scheme for the saturated systems. [ABSTRACT FROM AUTHOR]

Here, a dual-wavelength ratiometric electrochemiluminescence (ECL) approach is reported based on resonance energy transfer (RET) from graphite-like carbon nitride nanosheet (g-C3N4 NS) to Ru(bpy)32+ for sensitive detection of microRNA (miRNA). In this approach, Au nanoparticles (Au NPs) functionalized g-C3N4 NS nanohybrid (Au-g-C3N4 NH) coated on glassy carbon electrode (GCE) could exhibit strong and stable ECL emissions with emission peak centered at 460 nm. The ECL emission at such wavelength matched well with the absorption peak of Ru(bpy)32+ as well as impeccably stimulating the emission of Ru(bpy)32+ at the wavelength of 620 nm, producing ECL-RET with high efficiency. Thus, based on the ECL signals quenching at 460 nm and increasing at 620 nm, a dual-wavelength ratiometric ECL-RET system was achieved. This system was then utilized for determination of target miRNA. With the attachment of thiol-modified molecular beacon on Au-g-C3N4 NH, target miRNA hybridized with the molecular beacon to form a DNA-RNA duplex. The obtained DNA-RNA duplex could be cleaved by duplex-spedfic nudease to release target miRNA which would take part in the next cyde for further hybridization. Finally, the introdudng of Ru(bpy)32+ was through the probe DNA-Ru(bpy)32+ complementary with the rest single-strand DNA on electrode. By measuring the ratio of ECL460 nm/ECL620 nm, we could accurately quantify the concentration of miRNA-21 in a wide range from 1.0 fM to 1.0 nM. This work provides an important reference for the study of dual-wavelength ECL ratiometry and also exhibits potential capability in the detection of nucleic adds. [ABSTRACT FROM AUTHOR]

[Objective] The aim was to explore interannual changes of soil nutrients in tobacco soils in Zhaotong, in order to provide theoretical references for tobacco balanced fertilization in Zhaotong. [Method] The research analyzed nutrient changes in tobacco soils in Zhaotong during 2011-2013. [Result] In Zhaotong, pH value of tobacco soils was increasing; the contents of organic matter and N, P and K contents were in the range suitable for tobacco growth; Cl- content was growing in tobacco soils and reached the highest in 2013. [Conclusion] In general, soil nutrients show insignificant differences intemannually in Zhaotong. [ABSTRACT FROM AUTHOR]

The pig breeding industry is one of the pillar industries of China's agriculture. The measurement of pig production efficiency, and the way to improve pig production efficiency through the measurement, thereby reducing pollution emissions, is of great significance to the development of China's pig industry. Existing research focuses on measuring the efficiency of pig breeding, while ignores the emissions of large amounts of pollutants in the breeding process, as well as the heterogeneity of scale and region. In view of this, based on the DEA model, this paper constructs a three-level Metafrontier-Malmquist-Luenberger index to evaluate the green total factor productivity of pig breeding (PBG) by considering negative output. The results indicate that: (i) China's PBG, overall, dropped by 0.34% from 2004 to 2018. In terms of scale, large-scale was the highest, medium-sized was the second and small-scale was the lowest. (ii) China's PBG is distributed in a stepped manner, with the highest in the eastern area, the second in the central area, and the lowest in the western area. The differences between regions and provinces are affected by factors, such as the level of economic development, the government's emphasis on the scale of pig breeding and local resource conditions. (iii) The three decomposition efficiencies of PBG are manifested in the decline of scale structure efficiency and management efficiency, and the improvement of technical efficiency. Among them, the low efficiency of scale structure is the leading reason for the decline of overall PBG. According to the above empirical results, this article finally puts forward policy suggestions and environmental protection recommendations for pig breeding to improve PBG. • Add negative output into the evaluation system of pig breeding efficiency. • The scale heterogeneity and regional heterogeneity of PBG were considered. • Construct three-levels DDF-MML model, namely meta-frontier, scale frontier and regional frontier. • Decompose PBG into scale structure efficiency, technical efficiency and management level. • Select the data in China's 17 major pig production areas from 2004 to 2018. [ABSTRACT FROM AUTHOR]

Reliable wind modelling is of crucial importance for wind farm development. The common practice of using sector-wise Weibull distributions has been found inappropriate for wind farm layout optimization. In this study, we propose a simple and easily implementable method to construct joint distributions of wind speed and wind direction, which is based on the parameters of sector-wise Weibull distributions and interpolations between direction sectors. It is applied to the wind measurement data at Horns Rev and three different joint distributions are obtained, which all fit the measurement data quite well in terms of the coefficient of determination R2. Then, the best of these joint distributions is used in the layout optimization of the Horns Rev 1 wind farm and the choice of bin sizes for wind speed and wind direction is also investigated. It is found that the choice of bin size for wind direction is especially critical for layout optimization and the recommended choice of bin sizes for wind speed and wind direction is finally presented. [ABSTRACT FROM AUTHOR]

The authors reflect on mass extinction at the end of Permian period. Topics discussed include causes of mass extinction such as Siberian flood basalt volcanism, marine anoxia and euxinia and biogenic methane release due to explosive growth of a methanogenic microbe; evidence of a cyanobacterial bloom at Meishan; and association of the Triassic recovery with a number of repeated large carbon isotope excursions.

Volcanism and impact scenarios are two of the most plausible ways of interpreting the causes of the largest biological mass extinction at the end-Permian. Microspherules have previously been widely reported from tens of different Permian-Triassic boundary (PTB) sections in South China and some other regions. These microspherules have been interpreted as either the product of volcanic eruptions or an impact event. In order to test these scenarios, we collected 60 samples from 12 intensively-studied PTB sections in South China. In addition, four soil samples close to these PTB layers were also collected for comparison. Our investigation indicates that abundant microspherules with mosaic or dot shape crystals on rounded surface are present in the surface samples in the PTB layers at Meishan, Meili, and Shatian sections and most soil background samples in South China. Those microspherules consist of four different types based on their main chemical composition, surface features, and internal structure including iron, magnetite-silicate, glassy, pyrite microspherules and framboids. In contrast, microspherules have not been found in a few sections in remote areas such as the Selong Xishan section in Tibet and the Dalongkou section in Xinjiang, Northwest China, in the deeply-excavated samples at the Shangsi section and the hard tuff layers around the PTB at the Xiaochehe Section in Guiyang. Microspherules decrease in abundance with depth in PTB clay beds. All these microspherules except the pyrite microspherules and framboids are found in both the PTB layers and the nearby soil background samples. The iron microspherules are pure iron oxides such as magnetite, hematite or maghemite and contain low concentrations of nickel and chromium, and lack an Ni-Fe core and general extraterrestrial mineral wüstite. All these external and chemical characteristics suggest that most of iron microspherules previously reported from PTB sections in South China are modern industrial fly ashes. A low ratio of Fe3 +/FeTotal in crystals of magnetite-silicate microspherules and high ZnO contents can identify them as industrial contaminants. The pyrite microspherules and framboidal pyrite found from bed 24e and bed 26 at the Meishan sections are of depositional or/and diagenetic origins, and only the rounded quartz and the fragments containing extremely high SiO2 and TiO2 are possibly of volcanic origin. [ABSTRACT FROM AUTHOR]

Meishan Section D with the Wuchiapingian/Changhsingian and Permian/Triassic GSSPs has become the most intensively studied section because it records the whole process of the largest biological extinction during the Phanerozoic. Numerous data including high-precision geochronology, multiple isotope chemostratigraphy, magnetostratigraphy, and high-resolution multiple fossil biostratigraphy have been determined during the last decade. Conodonts are very abundant in the Changhsingian Stage at the Meishan sections and their biostratigraphy together with geochronologic and multiple geochemical data provide a basic temporal framework to calibrate the end-Permian mass extinction and realize global correlation between sections at Meishan and those in other regions of the world. However, major discrepancies exist in various previous studies of conodonts from the Meishan sections. Many different authors have documented very different species ranges based on different concepts and approaches of taxonomy. We here employ a sample population approach to revise and refine the high-resolution conodont biostratigraphic framework for the Changhsingian Stage and end-Permian mass extinction interval across the Permian-Triassic boundary (PTB) at the Meishan sections. Eight zones are recognized from the latest Wuchiapingian to the basal Triassic. They are, in ascending order, the Clarkina longicuspidata Zone in the uppermost Wuchiapingian; the Clarkina wangi Zone, Clarkina subcarinata Zone, Clarkina changxingensis Zone, Clarkina yini Zone, Clarkina meishanensis Zone, Clarkina zhejiangensis-Hindeodus changxingensis Zone in the Changhsingian Stage, and the Hindeodus parvus Zone in the basal Triassic. Conodont evolutionary lineages for the whole Changhsingian are also tentatively established. All species are described in detail and growth series of different specimens for valid species are figured as completely as possible. The temporal relationship of each conodont zone with geochemical excursions, geochronologic calibration and magnetostratigraphical polarity zones are provided, which is critical to understand the tempo of the end-Permian mass extinction. [ABSTRACT FROM AUTHOR]

The emissions trading system, a crucial and fundamental system reform in the environmental resources field of China, was established to promote the continuous and effective reduction of total emissions of major pollutants. In this context, based on the panel data of 285 Chinese cities (except Tibet) from 2004 to 2018, this paper uses the quasi-experimental method of Difference in Difference to assess the effect of the emissions trading system introduced on sulfur dioxide emissions of China and the transmission mechanism. The article generates several intriguing findings. (1) The emissions trading system has a significant suppressive effect on sulfur dioxide emissions. (2) Mechanistic tests show that the emissions trading system can effectively suppress sulfur dioxide emissions by reducing government intervention, stimulating green patent innovation, and improving resource use efficiency, in which green utility patents have a masking effect. (3) From the east, central and west divisions, the emissions trading system has a significant suppression effect on sulfur dioxide emission in the eastern and central regions, and the eastern region is better than the central region. (4) In terms of factor endowment, the emissions trading system has a significant suppression effect on sulfur dioxide emissions in both resource-based and non-resource-based cities, with non-resource-based cities outperforming resource-based cities; while within resource-based effect exists only in regenerative cities. (5) The emissions trading system has a significant suppression effect on sulfur dioxide emissions in old and non-old industrial base cities in industrial base zoning. The suppression effect in non-old industrial base cities is better than that in old industrial base cities. This paper provides empirical evidence for evaluating the emissions trading system at the provincial level in China and suggests policy recommendations for selecting government tools to effectively curb sulfur dioxide emissions. Although the emissions trading system has made an outstanding contribution to sulfur dioxide emissions reduction, there is still much space for further development of potential emission reductions. [ABSTRACT FROM AUTHOR]

In many surveillance sensor networks, sensors are scheduled to work in a duty-cycled mode (i.e., periodically switching between active states and sleeping states) in order to prolong the network lifetime. The duty-cycled mode saves sensors' energy but brings other issues. In surveillance applications (e.g., forest fire alarm or intruder detection), it is desired to report detected events to the sink node as soon as possible. However, the duty-cycled mode may increase the data delivery latency. In this paper, we study minimum-delay routing in duty-cycled surveillance sensor networks. As the minimum-delay routes are time dependent (i.e., they change with time) in duty-cycled sensor networks, routing becomes a challenging task. We propose a distributed routing algorithm to find the minimum-delay routes at anytime from all nodes to the sink node. Further, all minimum-delay routes can be found in one execution of our routing algorithm. We further provide a distributed route maintenance algorithm for finding the minimum-delay routes when the network dynamically changes. We theoretically prove the correctness of the proposed algorithm, and extensive simulation results show that the performance of our algorithm outperforms other existing algorithms. [ABSTRACT FROM AUTHOR]

The correlation between the fusulinid-based Tethyan and the conodont-based international timescales of the Permian System has become one of themost disputed issues among the Permian community during the past two decades. In this paper, we document a conodont fauna consisting of four species including Sweetognathus guizhouensis, Pseudohindeodus augustus, Hindeodus permicus and a new genus Meiognathus pustulus from the lower part of a large exotic limestone block at Hatahoko in the Nyukawa area, Gifu Prefecture, central Japan, which all suggest aKungurian age. The Kungurian age indicated by the conodonts is consistent with the age of the associated brachiopods, but conflicts with the Murgabian age indicated by the associated fusulinids including Cancellina nipponica, Neoschwagerina simplex, Neofusulinella praecursor etc. This co-occurrence of Kungurian conodonts and Murgabian fusulinids in central Japan suggests that previously unrecognized temporal distributions of some key fusulinid or conodont elements need to be clarified and that the intensively-disputed correlation problem between theKungurian containing theMurgabian fusulinids at the Luodian section in Guizhou, South China with the strata containing the ammonoid Waagenoceras in Oman and Sicily was caused by artificial conodont taxonomic discrepancies. The Luodian section in South China could serve as a key reference section for the correlation of the Kungurian Stage (late Early Permian) between the Tethyan and international timescales. [ABSTRACT FROM AUTHOR]

The article discusses research into the chronology and possible causes of the mass extinction event at the end-Permian of the Phanerozoic era. Biodiversity data from sediments in South China was studied, including the mass spectrometric geochronological, isotopic, and biostratigraphic information from several sites. The results indicate that the mass extinction occurred in marine and terrestrial ecosystems 252.28 ± 0.08 million years ago over the course of 20,000 years or more, and point toward thermogenic carbon dioxide or methane emissions as possible causes of the extinction event.

Twelve brachiopod species are described from the Cisuralian (Early Permian) Kungurian horizon of a large limestone block in the Middle Jurassic accretionary complex at Hatahoko in the Mino Belt, central Japan. Most species of the Hatahoko fauna are known from the Kungurian to lowest Guadalupian (Middle Permian) of West Texas, U.S.A. The Kungurian age is also indicated by the associated conodonts in the same limestone block. The Hatahoko brachiopod fauna, as well as some other previously-reported Guadalupian brachiopod faunas, exhibits a very strong paleobiogeographical affinity with the faunas in West Texas, U.S.A. Therefore it can be interpreted as a fauna which inhabited reef-seamount complexes close to North America in the mid-equatorial region of the Panthalassa in the late Early Permian, rifted westwards thousands of kilometers, and finally accreted onto the Japanese Island when the Western Pacific Plate subducted beneath the Eurasian Plate during the Jurassic. [ABSTRACT FROM AUTHOR]

The article presents case studies of six Hepatic epithelioid Hepatic (HEH) patients. Their past history indicated that one of them had a history of hepatic schistosomiasis while the others had no liver disease. Two were asymptomatic and the others complained of upper abdominal discomfort or pain and hepatomegaly. The article discusses the treatments for HEH which include liver transplantation, chemotherapy or radiotherapy and liver surgery.

Mycoplasma gallisepticum is a major etiological agent of chronic respiratory disease (CRD) in chickens and sinusitis in turkeys. The pleuromutilin antibiotics tiamulin and valnemulin are currently used in the treatment of M. gallisepticum infection. We studied the in vitro development of pleuromutilin resistance in M. gallisepticum and investigated the molecular mechanisms involved in this process. Pleuromutilin-resistant mutants were selected by serial passages of M. gallisepticum strains PG31 and S6 in broth medium containing subinhibitory concentrations of tiamulin or valnemulin. A portion of the gene encoding 23S rRNA gene (domain V) and the gene encoding ribosome protein L3 were amplified and sequenced. No mutation could be detected in ribosome protein L3. Mutations were found at nucleotide positions 2058, 2059, 2061, 2447 and 2503 of 23S rRNA gene ( Escherichia coli numbering). Although a single mutation could cause elevation of tiamulin and valnemulin MICs, combinations of two or three mutations were necessary to produce high-level resistance. All the mutants were cross-resistant to lincomycin, chloramphenicol and florfenicol. Mutants with the A2058G or the A2059G mutation exhibited cross-resistance to macrolide antibiotics erythromycin, tilmicosin and tylosin. [ABSTRACT FROM AUTHOR]

This paper investigates the adaptive synchronization of hyperchaotic Lü systems based on the method of extended passive control. By combining the feedback control, the extended passive control method with two output variables is developed, which can synchronize hyperchaotic Lü systems asymptotically and globally more easily without knowing the bound of state of the hyperchaotic system. Adaptive laws are introduced to estimate the unknown parameters as well. Simulation results show the effectiveness and flexibility of the proposed control scheme. [ABSTRACT FROM AUTHOR]

Excessive burst firing of action potentials in subthalamic nucleus (STN) neurons has been correlated with the brady kinesia and rigidity seen in Parkinson's disease. Consequently, there is much interest in characterizing mechanisms that promote burst firing, such as the regulation of NMDA receptor function. Using whole-cell recording techniques in rat brain slices, we report that inward currents evoked by NMDA are greatly potentiated by ATP-sensitiveK+(K-ATP) channel blocking agents in STN neurons but not in dopamine neurons in the substantia nigra. Moreover, we found that the ability of NMDA to evoke K-ATP current was blocked by inhibitors of nitric oxide synthase, guanylyl cyclase, and calcium/calmodulin. By altering firing patterns of STN neurons, this NMDA/K-ATP interaction may exert an important influence on basal ganglia output and thereby affect the clinical expression of Parkinson's disease. [ABSTRACT FROM AUTHOR]

A series of well-defined graft copolymers, consisting of poly(tert-butyl acrylate) backbone and poly(methyl acrylate) side chains, were synthesized by the combination of reversible addition−fragmentation chain transfer (RAFT) polymerization and atom transfer radical polymerization (ATRP). A new acrylate monomer containing ATRP initiation group, tert-butyl 2-((2-bromopropanoyloxy)methyl)acrylate, was first prepared, which can be homopolymerized or copolymerized with tert-butyl acrylate by RAFT in a controlled way to obtain well-defined homopolymers and copolymers with narrow molecular weight distributions (Mw/Mn< 1.18). The reactivity ratios were determined by Fineman−Ross and Kelen−Tudos methods, respectively. The density of ATRP initiating groups can be tuned by the feed ratio of the comonomers. These polymers directly initiated ATRP of methyl acrylate to synthesize well-defined poly(tert-butyl acrylate)-g-poly(methyl acrylate) graft copolymers (Mw/Mn< 1.28) with controllable grafting densities via the grafting-from strategy without any polymeric functional group transformation. Finally, the poly(tert-butyl acrylate) backbone was selectively hydrolyzed in acidic environment without affecting the poly(methyl acrylate) side chains to give poly(acrylic acid)-g-poly(methyl acrylate) amphiphilic graft copolymers. [ABSTRACT FROM AUTHOR]

Twenty-three species of silicified brachiopods are described from four samples in the middle and upper parts of the Episkopi Formation from Hydra Island, Greece. These brachiopods are newly recorded from the region and together with previously described brachiopods from the same localities constitute the most diverse Lopingian (Late Permian) brachiopod fauna reported in southern Europe. The brachiopod fauna is Wuchiapingian as indicated by the associated conodonts. The fauna from Hydra exhibits strong palaeobiogeographical links with the faunas from South China. In addition, palaeobiogeographical affinities with the faunas of Thailand and the northern peri-Gondwanan region are also present, which implies a peri-Gondwanan origin for Hydra. Palaeoecologically, the brachiopod assemblage from sample EP in the middle part of the Episkopi Formation is dominated by pedically-attached and cementing genera and reflects moderate energy conditions above storm wave base and an abundance of hard substrates provided by sponges in the biohermal habitat. By contrast, the brachiopod assemblage in the other three samples from the upper part of the Episkopi Formation is dominated by spinose genera with a free-resting life habit, suggesting soft substrates in a quiet water environment below storm wave base on the outer part of the shelf. New taxa are Petinospiriferina gen. nov., Hustedia episkopiensis sp. nov., Waterhouseiella hydraensis sp. nov. and Xenosaria tenuis sp. nov. [ABSTRACT FROM AUTHOR]

Self-assembly behavior of a double-bond-based amphiphilic graft copolymer consisting of hydrophobic polyallene backbone and hydrophilic poly(ethylene glycol) side chains in tetrahydrofuran (THF)/water was investigated. Polyallene backbone was first prepared via living coordination polymerization of 6-methyl-1,2-heptadien- 4-ol (MHDO) initiated by [(η3-allyl)NiOCOCF3]2. The targeted amphiphilic graft copolymer with relative narrow molecular weight distribution (Mw/Mn= 1.22) was synthesized by the coupling reaction between the pendant hydroxyls of the backbone and acyl chloride end group of poly(ethylene glycol) via the grafting-onto approach. The critical micelle concentration (cmc) was determined by the fluorescence probe technique. Micelle morphologies could be well tuned by water content, initial copolymer content, and ion strength. In particular, this kind of achiral copolymer could aggregate to form chiral helical nanostructures under given conditions. [ABSTRACT FROM AUTHOR]

The flow-acoustic splitting technique for aeroacoustic computations is extended to simulate the propagation of acoustic waves generated by three-dimensional turbulent flows. In the flow part, a subgrid-scale turbulence model (the mixed model) is employed for large-eddy simulations. The obtained instantaneous flow solution is employed as input for the acoustic part. At low Mach numbers, the differences in scales and propagation speed between the flow and the acoustic field are quite large, and hence different meshes and time steps can be used for the two parts. The model is applied to compute flows past a NACA 0015 airfoil at a Mach number of 0.2 and a Reynolds number of 1.6 x 105 for different angles of attack. The flow solutions are validated by comparing lift and drag characteristics with experimental data. The comparisons show good agreements between the computed and measured airfoil lift characteristics for angles of attack up to stall. For the acoustic solutions, predicted noise spectra are validated quantitatively against experimental data. A parametrical study of the noise pattern for flows at angles of attack between 4 and 12 deg shows that the noise level is small for angles of attack below 8 deg, increases sharply from 8 to 10 deg, and reaches a maximum at 12 deg. [ABSTRACT FROM AUTHOR]

China is a large country of egg consumption, the study on China's laying hens breeding green total factor productivity (LHBG) is conducive to reducing pollution emissions while improving the productivity of laying hens to promote the cleaner production. Obviously, existing studies on laying hens breeding neglect regional and scale differences as well as serious pollution issues. Therefore, based on the directional distance function (DDF) - Data Envelopment Analysis (DEA) model, this paper constructs a three-level Metafrontier-Malmquist-Luenberger (MML) index, considering negative output, to evaluate LHBG from 2004 to 2018. Firstly, in terms of scale, the results show that LHBG is the largest in middle scale, followed by small scale and large scale. Secondly, from a regional point of view, the results indicate that China's LHBG presents a reverse stair-step distribution, that is, LHBG is the lowest in the eastern region, followed by the central region and the highest in the western region. The differences between regions and provinces are affected by the traditional farming habits, non-agricultural employment opportunities, the level of urbanization and resource conditions. Thirdly, this paper obtained that the three decomposition efficiencies of LHBG are manifested as the decrease in management efficiency, and the increase in scale structure efficiency and technical efficiency. Fourthly, climate factors have an impact on the laying hens breeding. According to the empirical results, this paper finally puts forward policy suggestions for improving LHBG and environmental protection policy recommendations for layer breeding. • Research on the efficiency of China's laying hens, which subject is innovative. • Environmental factors are introduced into the evaluation system. • The scale heterogeneity and regional heterogeneity of laying hens are considered. • Construct three-levels DDF-MML model and decompose into three efficiencies. [ABSTRACT FROM AUTHOR]

The uppermost 5-15 m of the Douling Formation in the southern Hunan area, South China, yields a diverse fauna comprised of ammonoids, bivalves, and brachiopods. The brachiopods reported in this paper consist of 51 species in 34 genera and are dominated by the Lopingian (Late Permian) species associated with a few species persisting from the underlying Maokouan (Late Guadalupian). This fauna is of earliest Wuchiapingian in age as precisely constrained by the associated conodont Clarkina postbitteri postbitteri and the Guadalupian-type ammonoid fauna of the Roadoceras-Doulingoceras Zone in the brachiopod horizon. The discovery of the Lopingian species-dominated brachiopod fauna in the earliest Wuchiapingian in southern Hunan suggests a much less pronounced effect of the pre-Lopingian crisis (end-Guadalupian mass extinction) than the end-Changhsingian mass extinction in terms of brachiopods, a contemporaneous Onset of the Lopingian recovery/radiation during the pre-Lopingian crisis period, and taxonomic selectivity of the pre-Lopingian crisis in terms of different fossil groups. New taxa are Echinauris doulingensis n. sp., Pararigbyella quadrilobata n. gen. and n. sp. and P. doulingensis n. gen. and n. sp. [ABSTRACT FROM AUTHOR]

A series of well-defined asymmetric centipede-like copolymers, containing polyacrylate backbone, hydrophilic poly(ethylene glycol), and hydrophobic polystyrene side chains, was synthesized by successive atom transfer radical polymerization. The grafting-through strategy was first employed for the preparation of polypoly(ethylene glycol) methyl ether acrylate comb copolymer. The grafting-from route was used following for the synthesis of the final amphiphilic centipede-like copolymer, polypoly(ethylene glycol) methyl ether acrylate-g-polystyrene. At each grafting point, two different chains are connected and the spacing between the grafting points is constant. Polystyrene side chains were connected to the polyacrylate backbone through stable C−C bonds instead of ester connections. The molecular weights of both the backbone and the side chains were controllable. The molecular weight distributions were in the range of 1.24−1.38. The critical micelle concentrations of these amphiphilic centipede-like graft copolymers in water were determined by fluorescence probe technique. The morphologies of the micelles formed from these centipede-like graft copolymers were preliminarily explored by TEM and were found to be spheres. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Liver fibrosis is a prelude of liver cirrhosis. Currently the molecular mechanism of liver fibrosis is not clear. The purpose of this study is to screen the abnormally expressed genes of liver fibrosis and to illustrate the changes of Smurf2 expression in the process of liver fibrosis. METHODS: A liver fibrosis model was established in rats by injection of tetrachlormethane (CCl4). A cDNA microarray analysis was performed on the liver at mid-stage of fibrosis. Thereafter, a semi-quantitative RT-PCR, Western blot analysis and immunohistochemistry test were performed for determining Smurf2, Smad2 and SnoN at week 1, 2, 4 and 8 of establishing the liver fibrosis model. RESULTS: Smurf2, FGG, PTAFR, CYP2D6, among others, increased in the fibrosis liver and a semi-quantitative RT-PCR confirmed the reliability of the cDNA microarray analysis. Smurf2 in the liver fibrosis model group was at the same level as that of control group at week 1, but decreased at week 2 and 8 and increased at the week 4. Smad2 increased at week 2 and 8 but increased at week 4. However, Smad2 mRNA increased to the same level at week 4 as that at week 2 and 8. The decrease of Smad2 at week 4 may be due to the enhancement of ubiquitination and proteolytic degradation of Smad2 by the increase of Smurf2. SnoN decreased at week 4 and 8 because of the ubiquitination and degradation caused by Smurf2. The decrease of SnoN may explain the progress of liver fibrosis in spite of the decrease of Smad2 at week 4. CONCLUSION: This study screened the abnormally expressed genes of liver fibrosis and illustrated the changes of Smurf2, Smad2 and SnoN during the process of liver fibrosis. [ABSTRACT FROM AUTHOR]

In the paper we present a correction model for wall interference on rotors of wind turbines or propellers in wind tunnels. The model, which is based on a one-dimensional momentum approach, is validated against results from Navier-Stokes computations using a generalized actuator disc principle. In the model the exchange of axial momentum between the tunnel and the ambient room is represented by a simple formula, derived from actuator disc computations. The correction model is validated against Navier-Stokes computations of the flow about a wind turbine rotor. Generally, the corrections from the model are in very good agreement with the computations, demonstrating that one-dimensional momentum theory is a reliable way of predicting corrections for wall interference in wind tunnels with closed as well as open cross sections. [ABSTRACT FROM AUTHOR]

The subthalamic nucleus (STN) plays an important role in movement control by exerting its excitatory influence on the substantia nigra pars reticulata (SNR), a major output structure of the basal ganglia. Moreover, excessive burst firing of SNR neurons seen in Parkinson's disease has been attributed to excessive transmission in the subthalamonigral pathway. Using the ‘blind’ whole-cell patch clamp recording technique in rat brain slices, we found that focal electrical stimulation of the STN evoked complex, long-duration excitatory postsynaptic currents (EPSCs) in SNR neurons. Complex EPSCs lasted 200–500 ms and consisted of an initial monosynaptic EPSC followed by a series of late EPSCs superimposed on a slow inward shift in holding current. Focal stimulation of regions outside the STN failed to evoke complex EPSCs. The late component of complex EPSCs was markedly reduced by ionotropic glutamate receptor antagonists (2-amino-5-phosphonopentanoic acid and 6-cyano-7-nitro-quinoxalone) and by a GABAA receptor agonist (isoguvacine) when these agents were applied directly to the STN using a fast-flow microapplicator. Moreover, the complex EPSC was greatly enhanced by bath application of the GABAA receptor antagonists picrotoxin or bicuculline. These data suggest that recurrent glutamate synapses in the STN generate polysynaptic, complex EPSCs that are under tonic inhibition by GABA. Because complex EPSCs are expected to generate bursts of action potentials in SNR neurons, we suggest that complex EPSCs may contribute to the pathological burst firing that is associated with the symptoms of Parkinson's disease. [ABSTRACT FROM AUTHOR]

A numerical investigation of oscillatory instability is presented for axisymmetric swirling flow in a closed cylinder with rotating top and bottom. The critical Reynolds number and frequency of the oscillations are evaluated as function of the ratio of angular velocities of the bottom and the top (ξ=Ωbottom/Ωtop). Earlier linear stability analysis (LSA) using the Galerkin spectral method by Gelfgat et al. [Phys. Fluids, 8, 2614 (1996)] revealed that the curve of the critical Reynolds number behaves like an “S” around ξ=0.54 in the co-rotation branch and around ξ=-0.63 in the counter-rotation branch. Additional finite volume computations, however, did not show a clear S behavior. In order to check the existence of the S shape, computations are performed using an axisymmetric finite volume Navier-Stokes code at aspect ratios (λ=H/R) 1.5 and 2.0. Comparisons with LSA at λ=1.5 show that the S shape does exist. The S shape of the stability diagram predicted by LSA is thus confirmed by a finite-volume based Navier-Stokes solver. The additional computations at aspect ratio λ=2 show that the curve of critical Reynolds number has a wider S shape in the co-rotating branch for ξ about 0.7 whereas a sharp “beak” appears in the counter-rotating branch for ξ approximately -0.5. [ABSTRACT FROM AUTHOR]

Focuses on the proposal of a new subfamily of Lyttoniidae Waagen from the genus Brachiopoda based on the Guadalupin Xiala Formation in northern Tibet. Subdivision of the Xiala Formation into stratigraphical units at the Xinji section; Morphology of Lyttoniidae; Similarity of the new subfamily of Lyttoniidae Waagen to Oldhamina decipiens.

This paper describes a unique deepwater brachiopod fauna from the upper part of the Talung Formation at the Dongpan Section, southern Guangxi, South China. This brachiopod fauna includes 10 species belonging to 10 genera. New taxa are Anidanthus mucronata n. sp., Dongpanoproductus elegans n. gen. and sp., Costatumulus dongpanensis n. sp., and Spinomarginifera semicircridge n. sp. This fauna is characterized by small, thin-shelled species with high abundance and low diversity, and therefore is different in generic and species composition from the coeval faunas of the Late Permian limestone facies in South China. The brachiopod fauna can be safely assigned to the latest Changhsingian as indicated by the presence of abundant Paracrurithyris pigmaea, the immediately underlying radiolarian Neoalbaillella optima Zone of late Changhsingian age, and the overlying ammonoid Ophiceras sp. cf. O. tingi Tien of the lowest Triassic. This fauna is most likely to have lived in a deepwater environment as indicated by coexistence with the radiolarian Latentifistularia, small thin-shelled brachiopods, and the dominance of silica-bearing mudstone. [ABSTRACT FROM AUTHOR]

A new tip loss correction initially developed for ID Blade Element/Momentum (BEM) computations (submitted to Wind Energy), is now extended to 2D Actuator Disc/Navier­Stokes (ADAVS) computations and 3D Actuator Line/Navier­Stokes (AL/NS) compute lions. In the paper, it is shown that the tip loss correction is an important and necessary step for actuator/Navier­Stokes models. Computed results are compared to experimental data and to results from BEM computations using the new tip correction as well as the original one of Glauert (Aerodynamic Theory Dover, New York, Chap. VII, Div. L, pp. 251–268). From the results it is concluded that the tip loss correction bas been correctly employed in the Navier–Stokes based actuator models. The results also demonstrate that the difference between actuator line and actuator disk based models may increase, especially for flows at a low tip speed ratio. Since the flows at a low tip speed ratio are too far to be considered as axisymmetrical flows, the actuator disk models that are based on axisymnzetrical flow behaviors may not be valid. [ABSTRACT FROM AUTHOR]

The technique of deep brain stimulation (DBS) has become a preferred surgical choice for the treatment of advanced Parkinson's disease. The subthalamic nucleus (STN) is presently the most promising target for such DBS. In this study, whole-cell patch-clamp recordings were made from 46 STN neurons in rat brain slices to examine the effect of high-frequency stimulation (HFS) of the STN on glutamatergic synaptic transmission in STN neurons. HFS, consisting of trains of stimuli at a frequency of 100 Hz for 1 min, produced three types of synaptic plasticity in 17 STN neurons. First, HFS of the STN induced short-term potentiation (STP) of evoked postsynaptic current (EPSC) amplitude in four neurons. STP was associated with a reduction in the EPSC paired-pulse ratio, suggesting a presynaptic site of action. Second, HFS of the STN generated long-term potentiation (LTP) of EPSC amplitude in eight neurons. Although the EPSC paired-pulse ratio was reduced transiently in the first 2 min following HFS, ratios measured 6–20 min after HFS were unchanged from control. This suggests that LTP is maintained by a postsynaptic mechanism. Third, HFS produced long-term depression (LTD) of EPSC amplitude in five STN neurons. LTD was associated with a significant increase in EPSC paired-pulse ratios, indicating a presynaptic site of action. These results suggest that HFS can produce long-term changes in the efficacy of synaptic transmission in the STN. HFS-induced synaptic plasticity might be one mechanism underlying the effectiveness of DBS in the STN as a treatment of advanced Parkinson's disease. Synapse 50:314–319, 2003. © 2003 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

A brachiopod fauna including 19 species of 17 genera from an exotic block in the Indus-Tsangpo suture zone in southern Tibet is described and illustrated. The brachiopod fauna is dominated by Maninia elegans and two new taxa: Jinomarginifera Ihazeensis gen. et sp. nov. and Zhejiangospirifer giganteus sp. nov. The fauna is closely comparable with those from the middle and upper parts of the Wargal Formation and the Chhidru Formation in the Salt Range of Pakistan, the Chitichun Limestone in southern Tibet, and the Basleo area of West Timor, and these correlations suggest a Wuchiapingian age. The fauna exhibits substantial links with both peri-Gondwanan and Cathaysian faunas, which may imply that it is a seamount biota originally located in the southern margin of the Neotethys during the Late Permian, and was later in the early Cenozoic) displaced and became sandwiched into younger marine deposits in the collision process between India and Eurasia. [ABSTRACT FROM AUTHOR]

Investigates the changes of body length in Caenorhabditis elegans. Increase in the ploidy of nuclei in the hypodermal syncytial cell; Causes of the reduction of hypodermal endoreduplication; Presence of cuticle collagen in hypodermal cells.

Analyzes the origin of pressure oscillations and proposes a remedy. Basis for finite difference and finite volume methods for solving the Navier-Stokes equations; Deviation and oscillation of the original scheme about flows past a circular cylinder; Analysis of the Rhie-Chow interpolation.