Background: The aim of the research was to evaluate the association between CRP (C-reactive protein), troponin I, d-dimer, creatinine, glucose, GFR (glomerular filtration rate) and LDL-C (low-density lipoprotei...Background: The aim of the research was to evaluate the association between CRP (C-reactive protein), troponin I, d-dimer, creatinine, glucose, GFR (glomerular filtration rate) and LDL-C (low-density lipoprotein cholesterol) levels at the admission and the results of thrombolytic therapy. Materials and methods: 113 patients who underwent thrombolytic therapy for acute ischemic stroke in Pauls Stradins Clinical University Hospital from 01.01.2015 to 01.01.2016 were studied retrospectively. Blood samples were collected in the emergency department. The neurological status was estimated using the NIHSS (National Institute of Health Stroke Scale). The efficacy of thrombolytic therapy was assessed by comparing NIHSS score at the admission and after treatment. Afterward all patients were divided into three groups-the major improvement (NIHSS 〉 4), minor improvement (NIHSS ≤ 4) and without any clinical effect. Results: Only the median levels of GFR were significantly (p = 0.015) lower in patients who did not have any clinical improvements after thrombolytic therapy as compared to patients with the major or minor improvements (60.0, IQR (interquartile range) 42.4-72.3 mL/min/1.73m2; 83.2, IQR 65.3-98.3 mL/min/1.73m2 and 75.9, IQR 59.2-94.6 mL/min/1.73m2). Based on the ROC (receiver operating characteristic) curve, the optimal cut-off value of GFR level as an indicator for prediction of worsen clinical outcome after thrombolytic therapy was projected to be 61.65 mL/min/1.73m2, which yielded a sensitivity of 71.4% and a specificity of 24.5%, the area under the curve was 0.788 (95% CI (confidence interval), 0.648-0.928). According Spearman rank correlation test was founded statistically significant indirect correlation between GFR level and NIHSS score after treatment (r = -0.410, p = 0.020) in patients with severe stroke (NIHSS 〉 14). Conclusions: GFR level lower than 61.65 mL/min/1.73m2 at the admission could predict as a worse outcome, especially in patients with severe stroke.展开更多
The precision of atmospheric dry delay model is closely correlated with the accuracy of GPS water vapor in the process of GPS (Global Position System) remote sensing. Radiosonde data (from 1996 to 2001) at Qingyuan ar...The precision of atmospheric dry delay model is closely correlated with the accuracy of GPS water vapor in the process of GPS (Global Position System) remote sensing. Radiosonde data (from 1996 to 2001) at Qingyuan are used to calculate the exact values of the atmospheric dry delay. Base on these calculations and the surface meteorological parameters, the local year and month correction models of dry delay at the zenith angle of 0° are established by statistical methods. The analysis result shows that the local model works better and is slight more sensitive to altitude angle than universal models and that it is not necessary to build models for each month due to the slight difference between year model and month model. Furthermore, when the altitude angle is less than 75°, the difference between curve path and straight path increases rapidly with altitude angle’s decrease.展开更多
Based on a linear model, the present study provides analytical solutions for ideal triple forcing sources similar to sea surface temperature anomaly (SSTA) pat- terns associated with El Nino-Southern Oscillation (E...Based on a linear model, the present study provides analytical solutions for ideal triple forcing sources similar to sea surface temperature anomaly (SSTA) pat- terns associated with El Nino-Southern Oscillation (ENSO) Modoki in winter. The ideal triple pattern is composed of an equatorially symmetric heat source in the middle and equatoriaUy asymmetric cold forcing in the southeast and northwest. The equatorially symmetric heat source excites low-level cyclonic circulation anomalies associated with Rossby waves in both hemispheres, while the northwest- ern and southeastern equatorially asymmetric cold sources induce low-level anomalous anticyclones associated with Rossby waves in the hemisphere where the forcing source is located. Low-level zonal winds converge toward the heat sources associated with Kelvin and Rossby waves. Due to unequal forcing intensity in the northwest and southeast, atmospheric responses around the equatorially symmetric forcing become asymmetric, and low-level cyclonic circulation anomalies in the Southern Hemisphere become greater than those in the Northern Hemisphere. Ascending (descending) flows coincide with heat (cold) sources, resulting in a double-cell structure over the regions of forcing sources. Ideal triple patterns similar to SSTA patterns associated with La Nina Modoki produce opposite atmospheric responses. The theoretical atmospheric responses are consistent with observed circulation anomalies associated with ENSO Modoki. Therefore, the theoretical solutions can explain the dynamics responsible for atmospheric circulation anomalies associated with ENSO Modoki events.展开更多
The vitamin D receptor (VDR) gene is a primary candidate gene for tuberculosis susceptibility, but results of previous studies are somewhat contradictory and underpowered. Thus, it is essential to further explore th...The vitamin D receptor (VDR) gene is a primary candidate gene for tuberculosis susceptibility, but results of previous studies are somewhat contradictory and underpowered. Thus, it is essential to further explore the association between VDR gene polymorphisms and risk of pulmonary tuberculosis (PTB). Methods: A systematic review and meta-analysis about the association between Fok[, TaqI, Apal and Bsm[ polymorphisms and PTB susceptibility was conducted. Statistical Package for Social Science (Version 13.0) and Review Manager (Version 4.2, The Cochrane Collaboration) were used to analyze the data reported in studies. Results: A total of 13 studies with 2 262 cases and 2 833 controls were involved in the FokI polymorphism, and the results showed FokI polymorphism was associated with PTB susceptibility (allele f vs F: OR=1.12, 95% CI=[1.02, 1.23]; the additive effect model ff vs FF: OR=1.40, 95%CI=[1.10, 1.77]; the recessive genetic model firs Ff+FF: OR=1.39, 95%CI=[1.12, 1.71]). No significant associations were observed between TaqI (15 studies with 3 031 cases and 3 132 controls), ApaI (7 studies with 1 495 cases and 1 922 controls), BsmI (6 studies with 919 cases and 1 250 controls) variants and PTB susceptibility. Conclusion: We found variant Fokl polymorphism of VDR gene may play a risky role in PTB development, and the genetic model was presumed to be recessive.展开更多
A 2.4GHz 0.18μm CMOS gain-switched single-end Low Noise Amplifier (LNA) and a passive mixer with no external balun for near-zero-IF (Intermediate Frequency)/RF (Radio Frequency) applications are described. The ...A 2.4GHz 0.18μm CMOS gain-switched single-end Low Noise Amplifier (LNA) and a passive mixer with no external balun for near-zero-IF (Intermediate Frequency)/RF (Radio Frequency) applications are described. The LNA, fabricated in the 0.18μm 1P6M CMOS technology, adopts a gain-switched technique to increase the linearity and enlarge the dynamic range. The mixer is an IQ-based passive topology. Measurements of the CMOS chip are performed on the FR-4 PCB and the input is matched to 50Ω. Combining LNA and mixer, the front-end measured performances in high gain state are: -15dB of Sll, 18.5dB of voltage gain, 4.6dB of noise figure, 15dBm of IIP3, 85dBm to -10dBm dynamic range. The full circuit drains 6mA from a 1.8V supply.展开更多
The Mekong supports one of the richest inland fisheries in the world, with many of the fish migrating long distance to spawn. Little is known about the fisheries and migration strategies of the Upper Mekong whilst it ...The Mekong supports one of the richest inland fisheries in the world, with many of the fish migrating long distance to spawn. Little is known about the fisheries and migration strategies of the Upper Mekong whilst it is supposed that many fish species move between the Lower and Upper Mekong. Most likely, natural fish migration in the river has been altered by dam construction across the mainstream of the Upper Mekong. In this paper, the interconnectivity of fish species between different sections of the Mekong and negative impacts of dams on migratory fish are studied. Of the 162 fish species in the Upper Mekong and the 869 species in the Lower Mekong, 61 species are common. Results show that there is no significant difference at order level between the UM and LM. Similarity coefficients are used to evaluate interconnectivity at species, genus and family levels among four different sections of the Upper Mekong with each other and with the Lower Mekong as a whole. The highest similarity is found between the middle and lower reach of the Upper Mekong at species and genus levels and the middle and upper reach at family level. Of the eight cascade dams, Mengsong Dam in planning is considered as the biggest threat to migratory fish from the Lower Mekong and should be particularly concerned.展开更多
Crimping is widely adopted in the production of large-diameter submerged-arc welding pipes. Traditionally, designers obtain the technical parameters for crimping from experience or by trial and error through experimen...Crimping is widely adopted in the production of large-diameter submerged-arc welding pipes. Traditionally, designers obtain the technical parameters for crimping from experience or by trial and error through experiments and the finite element(FE) method. However, it is difficult to achieve ideal crimping quality by these approaches. To resolve this issue, crimping parameter design was investigated by multi-objective optimization. Crimping was simulated using the FE code ABAQUS and the FE model was validated experimentally. A welding pipe made of X80 high-strength pipeline steel was considered as a target object and the optimization problem for its crimping was formulated as a mathematical model and crimping was optimized. A response surface method based on the radial basis function was used to construct a surrogate model; the genetic algorithm NSGA-II was adopted to search for Pareto solutions; grey relational analysis was used to determine the most satisfactory solution from the Pareto solutions. The obtained optimal design of parameters shows good agreement with the initial design and remarkably improves the crimping quality. Thus, the results provide an effective approach for improving crimping quality and reducing design times.展开更多
Related party transactions (RPTs) can be used by corporate insiders (e.g., managers, controlling shareholders) to expropriate corporate outsiders (e.g., minority shareholders). We argue that effective disclosure...Related party transactions (RPTs) can be used by corporate insiders (e.g., managers, controlling shareholders) to expropriate corporate outsiders (e.g., minority shareholders). We argue that effective disclosure of RPTs can eliminate or at least reduce expropriation phenomena by letting corporate outsiders assess the fairness of the transactions and identify the underlying conflicts of interest. We consider a sample of large RPTs carried out by listed corporations in Italy, a country that has been affected by significant corporate scandals in recent years. In particular, we analyse the content of several compulsory informative documents, required by CONSOB (the Italian Securities and Exchange Commission), concerning large RPTs. The focus of our content analysis is on the "warnings" sections of these documents that should convey clear and comprehensive information on potential risks and conflicts of interest. Our empirical results show that, while the "warnings" sections of the studied documents generally contain all the information required by existing rules, the depth of the information provided is often unlikely to be sufficient to communicate the implications of the RPTs. Thus, readers may not find the disclosed information adequate to evaluate the fairness of the transactions. Moreover, visual representations are rarely used in the informative documents. The use of such representations could allow companies to convey the structures and features of complex RPTs in a simpler and more direct way.展开更多
Meteorological conditions are vital to PM_(2.5)and ozone(O_(3))complex pollution.Herein,the T-mode principal com-ponent analysis method was employed to objectively classify the 925-hPa geopotential height field of Don...Meteorological conditions are vital to PM_(2.5)and ozone(O_(3))complex pollution.Herein,the T-mode principal com-ponent analysis method was employed to objectively classify the 925-hPa geopotential height field of Dongying from 2017 to 2022.Synoptic patterns associated with four pollution types-namely,PM_(2.5)-only pollution,O_(3)-only pollution,Co-occurring of PM_(2.5)and O_(3)pollution,Non-occurring of PM_(2.5)and O_(3)pollution-were characterized at different time scales.The results indicated that synoptic classes conducive to PM_(2.5)-only pollution were“high-pressure top front”,“offshore high-pressure rear”,and“high-pressure inside”,while those conducive to O_(3)-only pollution were“offshore high-pressure rear”,“subtropical high”,and“high and low systems”.The Co-occurring of PM_(2.5)and O_(3)pollution were influenced by high pressure,and the Non-occurring of PM_(2.5)and O_(3)pollution were linked to precipitation and strong northerly winds.The variation in dominant synoptic patterns is crucial in the frequency changes of the four pollution types,which was further validated through the analysis of typical cases.Under the favorable meteorological conditions of high-pressure control with strong northerly winds or a subtropical high and inverted trough both with strong precipitation,there is potential to achieve coordinated control of PM_(2.5)and O_(3)in Dongying.Additionally,measures like artificially manipulating local humidity could be adopted to alleviate pollution levels.This study reveals the importance of comprehending the meteorological factors contributing to the formation of PM_(2.5)and O_(3)complex pollution for the improvement of urban air quality in the Bohai Rim region of China when emissions are high and the concentration of air pollutants exhibits high meteorological sensitivity.展开更多
Genome-wide association study(GWAS) can be used to identify genes that increase the risk of psychiatric diseases.However,much of the disease heritability is still unexplained,suggesting that there are genes to be di...Genome-wide association study(GWAS) can be used to identify genes that increase the risk of psychiatric diseases.However,much of the disease heritability is still unexplained,suggesting that there are genes to be discovered.Functional annotation of the genetic variants may increase the power of GWAS to identify disease genes,by providing prior information that can be used in Bayesian analysis or in reducing the number of tests.Expression quantitative trait loci(eQTLs) are genomic loci that regulate gene expression.Genetic mapping of eQTLs can help reveal novel functional effects of thousands of single nucleotide polymorphisms(SNPs).The present review mainly focused on the current knowledge on brain eQTL mapping,and discussed some major methodological issues and their possible solutions.The frequently ignored problems of batch effects,covariates,and multiple testing were emphasized,since they can lead to false positives and false negatives.The future application of eQTL data in GWAS analysis was also discussed.展开更多
Animal behavior is remarkably variable at all taxonomic levels. Over the last decades, research on animal behavior has focused on understanding ultimate processes. Yet, it has progressively become more evident that to...Animal behavior is remarkably variable at all taxonomic levels. Over the last decades, research on animal behavior has focused on understanding ultimate processes. Yet, it has progressively become more evident that to fully understand beha- vioral variation, ultimate explanations need to be complemented with proximate ones. In particular, the mechanisms generating variation in sexual behavior remain an open question. Variation in aspects of brain morphology has been suggested as a plausible mechanism underlying this variation. However, our knowledge of this potential association is based almost exclusively on com- parative analyses. Experimental studies are needed to establish causality and bridge the gap between micro- and macroevolutio- nary mechanisms concerning the link between brain and sexual behavior. We used male guppies that had been artificially selected for large or small relative brain size to study this association. We paired males with females and scored the full known set of male and female sexual behaviors described in guppies. We found several previously demonstrated associations between male traits, male behavior and female behavior. Females responded more strongly towards males that courted more and males with more orange coloration. Also, larger males and males with less conspicuous coloration attempted more coerced copulations. However, courting, frequency of coerced copulation attempts, total intensity of sexual behavior, and female response did not differ between large- and small-brained males. Our data suggest that relative brain size is an unlikely mechanism underlying variation in sexual behavior of the male guppy. We discuss these findings in the context of the conditions under which relative brain size might affect male sexual behavior .展开更多
To evaluate measurement uncertainty for small sample size and measurement data from an unknown distribution, we propose a grey evaluation method of measurement uncertainty based on the grey relation coefficient. The u...To evaluate measurement uncertainty for small sample size and measurement data from an unknown distribution, we propose a grey evaluation method of measurement uncertainty based on the grey relation coefficient. The uncertainty of measurement is analyzed using grey system theory, and the defects of the grey evaluation model of measurement uncertainty (GEMU) are studied. We then establish an improved grey evaluation model of measurement uncertainty (IGEMU). Simulations show that the precision of IGEMU is greater than that of GEMU, and that sample size has only a small effect on the precision of IGEVU. In particular, IGEMU is applied to evaluating measurement uncertainty for small sample size and measurement data from an unknown distribution. The measurement uncertainty of total profile deviation, which is measured by the CNC gear measuring center, can be evaluated by a combination of IGEMU and the Monte Carlo method.展开更多
The effect of China's rapid development on Sino-US relations and the existing international order is an important theoretical issue in current international relations research. We use empirical research methods to ex...The effect of China's rapid development on Sino-US relations and the existing international order is an important theoretical issue in current international relations research. We use empirical research methods to explore whether and how China has influenced the results of US "vote-buying" in the United Nations General Assembly (UNGA) through foreign aid. We find that through the mechanisms of foreign policy preferences, vulnerability and credibility, Chinese foreign aid has decreased US manipulation of UNGA voting. However, this is not a subjective strategic choice on China's part but the objective result of Chinese economic development. Taking the game of Sino-US foreign aid in international politics as the entry point and squarely facing the structural contradictions and competition that exist between China and the US will help us understand not only the problems and obstacles China will encounter on its future developmental path, but also the necessity and difficulty of risk control in Sino-US relations.展开更多
This paper estimates the information-based trading using spatially selective noise filtration (SSNF) method. The SSNF method is a kind of filtration technique based on the different spatial correlation of the wavele...This paper estimates the information-based trading using spatially selective noise filtration (SSNF) method. The SSNF method is a kind of filtration technique based on the different spatial correlation of the wavelet transform at several adjacent scales. Using SSNF method, the information shock caused by the informed traders could be extracted from the prices effectively, then the PINs at different scales could be calculated. The measure of informed trading can capture some asymmetric information properties, which is consistent with some empirical consensuses. Furthermore, compared with the MLE method in EKOP model, the method has computational facilities in avoiding the overflow or underflow problem, the boundary solutions problem and the initial values problem. And the method could be applied to the high-frequency world in both order-driven and quote-driven market.展开更多
It is known that the inevitable interaction of the entangled qubits with their environments may result in the degradation of quantum correlation.We study the decoherence of two remote qubits under general local single...It is known that the inevitable interaction of the entangled qubits with their environments may result in the degradation of quantum correlation.We study the decoherence of two remote qubits under general local single-and two-sided amplitude-damping channel(ADC).By using concurrence,quantum discord and Clauser-Horne-ShimonyHolt(CHSH)inequality,we find that the relation between the residual quantum correlations and the initial ones are different.Recently,Wang et al.[Int.J.Theor.Phys.54(2015)5]showed that there exist a set of partially entangled states that are more robust than maximally entangled states in terms of the residual quantum correlation measured by concurrence,fully entangled fraction and quantum discord,respectively.Here we find that both in single-and two-sided ADC,only the evolution of CHSH inequality with the initial parameter is proportional to that of the initial nonlocality.That means the initial state with maximally nonlocality will retain its role in the evolution.It implies that the evolution of nonlocality may reveal the characteristics of quantum state better.Furthermore,we discuss the evolutions of the three different quantum measurements with the initial parameter under generalized amplitude damping channel(GADC)and find that they are all proportional to that of the initial state.展开更多
文摘Background: The aim of the research was to evaluate the association between CRP (C-reactive protein), troponin I, d-dimer, creatinine, glucose, GFR (glomerular filtration rate) and LDL-C (low-density lipoprotein cholesterol) levels at the admission and the results of thrombolytic therapy. Materials and methods: 113 patients who underwent thrombolytic therapy for acute ischemic stroke in Pauls Stradins Clinical University Hospital from 01.01.2015 to 01.01.2016 were studied retrospectively. Blood samples were collected in the emergency department. The neurological status was estimated using the NIHSS (National Institute of Health Stroke Scale). The efficacy of thrombolytic therapy was assessed by comparing NIHSS score at the admission and after treatment. Afterward all patients were divided into three groups-the major improvement (NIHSS 〉 4), minor improvement (NIHSS ≤ 4) and without any clinical effect. Results: Only the median levels of GFR were significantly (p = 0.015) lower in patients who did not have any clinical improvements after thrombolytic therapy as compared to patients with the major or minor improvements (60.0, IQR (interquartile range) 42.4-72.3 mL/min/1.73m2; 83.2, IQR 65.3-98.3 mL/min/1.73m2 and 75.9, IQR 59.2-94.6 mL/min/1.73m2). Based on the ROC (receiver operating characteristic) curve, the optimal cut-off value of GFR level as an indicator for prediction of worsen clinical outcome after thrombolytic therapy was projected to be 61.65 mL/min/1.73m2, which yielded a sensitivity of 71.4% and a specificity of 24.5%, the area under the curve was 0.788 (95% CI (confidence interval), 0.648-0.928). According Spearman rank correlation test was founded statistically significant indirect correlation between GFR level and NIHSS score after treatment (r = -0.410, p = 0.020) in patients with severe stroke (NIHSS 〉 14). Conclusions: GFR level lower than 61.65 mL/min/1.73m2 at the admission could predict as a worse outcome, especially in patients with severe stroke.
基金Sino-Italian Cooperation Project "An Integrated System for the Planning, Monitoring and Real-time Forecasting of Floods Risks"
文摘The precision of atmospheric dry delay model is closely correlated with the accuracy of GPS water vapor in the process of GPS (Global Position System) remote sensing. Radiosonde data (from 1996 to 2001) at Qingyuan are used to calculate the exact values of the atmospheric dry delay. Base on these calculations and the surface meteorological parameters, the local year and month correction models of dry delay at the zenith angle of 0° are established by statistical methods. The analysis result shows that the local model works better and is slight more sensitive to altitude angle than universal models and that it is not necessary to build models for each month due to the slight difference between year model and month model. Furthermore, when the altitude angle is less than 75°, the difference between curve path and straight path increases rapidly with altitude angle’s decrease.
基金supported by the National Basic Research Program of China (Grant No. 2010CB950400)the National Natural Science Foundation of China (Grant No. 41030961)the State Oceanic Administration of the People’s Republic of China
文摘Based on a linear model, the present study provides analytical solutions for ideal triple forcing sources similar to sea surface temperature anomaly (SSTA) pat- terns associated with El Nino-Southern Oscillation (ENSO) Modoki in winter. The ideal triple pattern is composed of an equatorially symmetric heat source in the middle and equatoriaUy asymmetric cold forcing in the southeast and northwest. The equatorially symmetric heat source excites low-level cyclonic circulation anomalies associated with Rossby waves in both hemispheres, while the northwest- ern and southeastern equatorially asymmetric cold sources induce low-level anomalous anticyclones associated with Rossby waves in the hemisphere where the forcing source is located. Low-level zonal winds converge toward the heat sources associated with Kelvin and Rossby waves. Due to unequal forcing intensity in the northwest and southeast, atmospheric responses around the equatorially symmetric forcing become asymmetric, and low-level cyclonic circulation anomalies in the Southern Hemisphere become greater than those in the Northern Hemisphere. Ascending (descending) flows coincide with heat (cold) sources, resulting in a double-cell structure over the regions of forcing sources. Ideal triple patterns similar to SSTA patterns associated with La Nina Modoki produce opposite atmospheric responses. The theoretical atmospheric responses are consistent with observed circulation anomalies associated with ENSO Modoki. Therefore, the theoretical solutions can explain the dynamics responsible for atmospheric circulation anomalies associated with ENSO Modoki events.
基金Supported by the National Natural Science Foundation of China (30700685)the Medical Science and Technology Research Project of Chongqing Municipal Health Bureau (2009-1-06)
文摘The vitamin D receptor (VDR) gene is a primary candidate gene for tuberculosis susceptibility, but results of previous studies are somewhat contradictory and underpowered. Thus, it is essential to further explore the association between VDR gene polymorphisms and risk of pulmonary tuberculosis (PTB). Methods: A systematic review and meta-analysis about the association between Fok[, TaqI, Apal and Bsm[ polymorphisms and PTB susceptibility was conducted. Statistical Package for Social Science (Version 13.0) and Review Manager (Version 4.2, The Cochrane Collaboration) were used to analyze the data reported in studies. Results: A total of 13 studies with 2 262 cases and 2 833 controls were involved in the FokI polymorphism, and the results showed FokI polymorphism was associated with PTB susceptibility (allele f vs F: OR=1.12, 95% CI=[1.02, 1.23]; the additive effect model ff vs FF: OR=1.40, 95%CI=[1.10, 1.77]; the recessive genetic model firs Ff+FF: OR=1.39, 95%CI=[1.12, 1.71]). No significant associations were observed between TaqI (15 studies with 3 031 cases and 3 132 controls), ApaI (7 studies with 1 495 cases and 1 922 controls), BsmI (6 studies with 919 cases and 1 250 controls) variants and PTB susceptibility. Conclusion: We found variant Fokl polymorphism of VDR gene may play a risky role in PTB development, and the genetic model was presumed to be recessive.
文摘A 2.4GHz 0.18μm CMOS gain-switched single-end Low Noise Amplifier (LNA) and a passive mixer with no external balun for near-zero-IF (Intermediate Frequency)/RF (Radio Frequency) applications are described. The LNA, fabricated in the 0.18μm 1P6M CMOS technology, adopts a gain-switched technique to increase the linearity and enlarge the dynamic range. The mixer is an IQ-based passive topology. Measurements of the CMOS chip are performed on the FR-4 PCB and the input is matched to 50Ω. Combining LNA and mixer, the front-end measured performances in high gain state are: -15dB of Sll, 18.5dB of voltage gain, 4.6dB of noise figure, 15dBm of IIP3, 85dBm to -10dBm dynamic range. The full circuit drains 6mA from a 1.8V supply.
基金Supported by National Natural Science Foundation of China (No. 40601096)
文摘The Mekong supports one of the richest inland fisheries in the world, with many of the fish migrating long distance to spawn. Little is known about the fisheries and migration strategies of the Upper Mekong whilst it is supposed that many fish species move between the Lower and Upper Mekong. Most likely, natural fish migration in the river has been altered by dam construction across the mainstream of the Upper Mekong. In this paper, the interconnectivity of fish species between different sections of the Mekong and negative impacts of dams on migratory fish are studied. Of the 162 fish species in the Upper Mekong and the 869 species in the Lower Mekong, 61 species are common. Results show that there is no significant difference at order level between the UM and LM. Similarity coefficients are used to evaluate interconnectivity at species, genus and family levels among four different sections of the Upper Mekong with each other and with the Lower Mekong as a whole. The highest similarity is found between the middle and lower reach of the Upper Mekong at species and genus levels and the middle and upper reach at family level. Of the eight cascade dams, Mengsong Dam in planning is considered as the biggest threat to migratory fish from the Lower Mekong and should be particularly concerned.
基金Project(Y2012035)supported by the Natural Science Foundation of Hebei Provincial Education Department,ChinaProject(12211014)supported by the Natural Science Foundation of Hebei Provincial Technology Department,China+2 种基金Project(NJZY14006)supported by the Inner Mongolia Higher School Science and Technology Research Program,ChinaProject(2014BS0502)supported by the Natural Science Foundation of Inner Mongolia,ChinaProject(135143)supported by the Program of Higher-level Talents Fund of Inner Mongolia University,China
文摘Crimping is widely adopted in the production of large-diameter submerged-arc welding pipes. Traditionally, designers obtain the technical parameters for crimping from experience or by trial and error through experiments and the finite element(FE) method. However, it is difficult to achieve ideal crimping quality by these approaches. To resolve this issue, crimping parameter design was investigated by multi-objective optimization. Crimping was simulated using the FE code ABAQUS and the FE model was validated experimentally. A welding pipe made of X80 high-strength pipeline steel was considered as a target object and the optimization problem for its crimping was formulated as a mathematical model and crimping was optimized. A response surface method based on the radial basis function was used to construct a surrogate model; the genetic algorithm NSGA-II was adopted to search for Pareto solutions; grey relational analysis was used to determine the most satisfactory solution from the Pareto solutions. The obtained optimal design of parameters shows good agreement with the initial design and remarkably improves the crimping quality. Thus, the results provide an effective approach for improving crimping quality and reducing design times.
文摘Related party transactions (RPTs) can be used by corporate insiders (e.g., managers, controlling shareholders) to expropriate corporate outsiders (e.g., minority shareholders). We argue that effective disclosure of RPTs can eliminate or at least reduce expropriation phenomena by letting corporate outsiders assess the fairness of the transactions and identify the underlying conflicts of interest. We consider a sample of large RPTs carried out by listed corporations in Italy, a country that has been affected by significant corporate scandals in recent years. In particular, we analyse the content of several compulsory informative documents, required by CONSOB (the Italian Securities and Exchange Commission), concerning large RPTs. The focus of our content analysis is on the "warnings" sections of these documents that should convey clear and comprehensive information on potential risks and conflicts of interest. Our empirical results show that, while the "warnings" sections of the studied documents generally contain all the information required by existing rules, the depth of the information provided is often unlikely to be sufficient to communicate the implications of the RPTs. Thus, readers may not find the disclosed information adequate to evaluate the fairness of the transactions. Moreover, visual representations are rarely used in the informative documents. The use of such representations could allow companies to convey the structures and features of complex RPTs in a simpler and more direct way.
基金jointly supported by the Ministry of Ecology and Environment of the People’s Republic of China[grant number DQGG202121]the Dongying Ecological and Environmental Bureau[grant number 2021DFKY-0779]。
文摘Meteorological conditions are vital to PM_(2.5)and ozone(O_(3))complex pollution.Herein,the T-mode principal com-ponent analysis method was employed to objectively classify the 925-hPa geopotential height field of Dongying from 2017 to 2022.Synoptic patterns associated with four pollution types-namely,PM_(2.5)-only pollution,O_(3)-only pollution,Co-occurring of PM_(2.5)and O_(3)pollution,Non-occurring of PM_(2.5)and O_(3)pollution-were characterized at different time scales.The results indicated that synoptic classes conducive to PM_(2.5)-only pollution were“high-pressure top front”,“offshore high-pressure rear”,and“high-pressure inside”,while those conducive to O_(3)-only pollution were“offshore high-pressure rear”,“subtropical high”,and“high and low systems”.The Co-occurring of PM_(2.5)and O_(3)pollution were influenced by high pressure,and the Non-occurring of PM_(2.5)and O_(3)pollution were linked to precipitation and strong northerly winds.The variation in dominant synoptic patterns is crucial in the frequency changes of the four pollution types,which was further validated through the analysis of typical cases.Under the favorable meteorological conditions of high-pressure control with strong northerly winds or a subtropical high and inverted trough both with strong precipitation,there is potential to achieve coordinated control of PM_(2.5)and O_(3)in Dongying.Additionally,measures like artificially manipulating local humidity could be adopted to alleviate pollution levels.This study reveals the importance of comprehending the meteorological factors contributing to the formation of PM_(2.5)and O_(3)complex pollution for the improvement of urban air quality in the Bohai Rim region of China when emissions are high and the concentration of air pollutants exhibits high meteorological sensitivity.
文摘Genome-wide association study(GWAS) can be used to identify genes that increase the risk of psychiatric diseases.However,much of the disease heritability is still unexplained,suggesting that there are genes to be discovered.Functional annotation of the genetic variants may increase the power of GWAS to identify disease genes,by providing prior information that can be used in Bayesian analysis or in reducing the number of tests.Expression quantitative trait loci(eQTLs) are genomic loci that regulate gene expression.Genetic mapping of eQTLs can help reveal novel functional effects of thousands of single nucleotide polymorphisms(SNPs).The present review mainly focused on the current knowledge on brain eQTL mapping,and discussed some major methodological issues and their possible solutions.The frequently ignored problems of batch effects,covariates,and multiple testing were emphasized,since they can lead to false positives and false negatives.The future application of eQTL data in GWAS analysis was also discussed.
文摘Animal behavior is remarkably variable at all taxonomic levels. Over the last decades, research on animal behavior has focused on understanding ultimate processes. Yet, it has progressively become more evident that to fully understand beha- vioral variation, ultimate explanations need to be complemented with proximate ones. In particular, the mechanisms generating variation in sexual behavior remain an open question. Variation in aspects of brain morphology has been suggested as a plausible mechanism underlying this variation. However, our knowledge of this potential association is based almost exclusively on com- parative analyses. Experimental studies are needed to establish causality and bridge the gap between micro- and macroevolutio- nary mechanisms concerning the link between brain and sexual behavior. We used male guppies that had been artificially selected for large or small relative brain size to study this association. We paired males with females and scored the full known set of male and female sexual behaviors described in guppies. We found several previously demonstrated associations between male traits, male behavior and female behavior. Females responded more strongly towards males that courted more and males with more orange coloration. Also, larger males and males with less conspicuous coloration attempted more coerced copulations. However, courting, frequency of coerced copulation attempts, total intensity of sexual behavior, and female response did not differ between large- and small-brained males. Our data suggest that relative brain size is an unlikely mechanism underlying variation in sexual behavior of the male guppy. We discuss these findings in the context of the conditions under which relative brain size might affect male sexual behavior .
基金supported by the National Natural Science Foundation of China (Grant Nos. 61108052 and 61108073)the Technology Program of the Educational Office of Hei Longjiang Province in China (Grant No.11553016)
文摘To evaluate measurement uncertainty for small sample size and measurement data from an unknown distribution, we propose a grey evaluation method of measurement uncertainty based on the grey relation coefficient. The uncertainty of measurement is analyzed using grey system theory, and the defects of the grey evaluation model of measurement uncertainty (GEMU) are studied. We then establish an improved grey evaluation model of measurement uncertainty (IGEMU). Simulations show that the precision of IGEMU is greater than that of GEMU, and that sample size has only a small effect on the precision of IGEVU. In particular, IGEMU is applied to evaluating measurement uncertainty for small sample size and measurement data from an unknown distribution. The measurement uncertainty of total profile deviation, which is measured by the CNC gear measuring center, can be evaluated by a combination of IGEMU and the Monte Carlo method.
文摘The effect of China's rapid development on Sino-US relations and the existing international order is an important theoretical issue in current international relations research. We use empirical research methods to explore whether and how China has influenced the results of US "vote-buying" in the United Nations General Assembly (UNGA) through foreign aid. We find that through the mechanisms of foreign policy preferences, vulnerability and credibility, Chinese foreign aid has decreased US manipulation of UNGA voting. However, this is not a subjective strategic choice on China's part but the objective result of Chinese economic development. Taking the game of Sino-US foreign aid in international politics as the entry point and squarely facing the structural contradictions and competition that exist between China and the US will help us understand not only the problems and obstacles China will encounter on its future developmental path, but also the necessity and difficulty of risk control in Sino-US relations.
基金supported by the National Natural Science Foundation of China under Grant Nos.71371023,71371024,71373017,71171146,and 71771008
文摘This paper estimates the information-based trading using spatially selective noise filtration (SSNF) method. The SSNF method is a kind of filtration technique based on the different spatial correlation of the wavelet transform at several adjacent scales. Using SSNF method, the information shock caused by the informed traders could be extracted from the prices effectively, then the PINs at different scales could be calculated. The measure of informed trading can capture some asymmetric information properties, which is consistent with some empirical consensuses. Furthermore, compared with the MLE method in EKOP model, the method has computational facilities in avoiding the overflow or underflow problem, the boundary solutions problem and the initial values problem. And the method could be applied to the high-frequency world in both order-driven and quote-driven market.
基金Supported by National Natural Science Foundation of China under Grant Nos.11204002,11274010,61073048,11005029the Specialized Research Fund for the Doctoral Program of Higher Education(20123401120003,20113401110002)+2 种基金the Key Project of Chinese Ministry of Education(Nos.211080,210092)the Key Program of the Education Department of Anhui Province under Grant No.KJ2012A020the"211"Project of Anhui University,the Talent Foundation of Anhui University,the personnel department of Anhui province
文摘It is known that the inevitable interaction of the entangled qubits with their environments may result in the degradation of quantum correlation.We study the decoherence of two remote qubits under general local single-and two-sided amplitude-damping channel(ADC).By using concurrence,quantum discord and Clauser-Horne-ShimonyHolt(CHSH)inequality,we find that the relation between the residual quantum correlations and the initial ones are different.Recently,Wang et al.[Int.J.Theor.Phys.54(2015)5]showed that there exist a set of partially entangled states that are more robust than maximally entangled states in terms of the residual quantum correlation measured by concurrence,fully entangled fraction and quantum discord,respectively.Here we find that both in single-and two-sided ADC,only the evolution of CHSH inequality with the initial parameter is proportional to that of the initial nonlocality.That means the initial state with maximally nonlocality will retain its role in the evolution.It implies that the evolution of nonlocality may reveal the characteristics of quantum state better.Furthermore,we discuss the evolutions of the three different quantum measurements with the initial parameter under generalized amplitude damping channel(GADC)and find that they are all proportional to that of the initial state.