variation

摘要： In order to study the electronic structure and the variation of chemical shift of the 181Ta nuclei in ternary A3BC4 semiconductor, the first-principles calculations are used by PBE-GGA, BJ, and TB-mBJ functionals. By comparing these three kinds of functionals, the results of TB-mBJ are more in line with the experimental values. The electronic structure calculated by TB-mBJ functional shows that TaCu3X4 (X = S, Se, Te) are indirect bandgap semiconductors and TaTl3X4 (X = S, Se) are direct bandgap semiconductors. By decomposing the chemical shifts contributed by the different orbitals, we found that the chemical shifts are related to the electronic structure. In this paper, the variation (up to 2500 ppm) of NMR chemical shift of 181Ta nuclei is related to the d orbital of Ta.

摘要： Recently,some severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants represented by B.1.7(Alpha),B.1.351(Beta),P1(Gamma),B.1.617(Delta)and B.1.529(Omicron)have higher transmission and pathogenicity.Especially,Omicron causes global panic because of its high mutation in infectivity and vaccine escape,and their emergence makes the epidemic more difficult to control.The latest research reports indicate that these new corona mutants may first be mutated in the special population of immunosuppressive patients,and long-term infection and artificial immunotherapy may promote the variation of SARS-CoV-2.Not only that,there are a large number of congenital or acquired immunosuppressive patients worldwide,and immunosuppressive patients infected with SARS-CoV-2 will also have different impacts on social public health security.Therefore,we should pay more attention to the immunosuppressive population.This paper will briefly analyze the correlation between immunosuppressive population and SARS-CoV-2 variation in the form of review.

摘要： The higher concentration of PM_(10) and PM_(2.5) in the lower atmosphere is severely harmful for human health and it also makes visibility diminution along with weather and climate modifications.The main objective is to find out the spatiotemporal variation and dispersal of PM_(10) and PM_(2.5) along with COVID-19 infection in the dusty city Kolkata.The consecutive two years PM_(10) and PM_(2.5) data of different stations have been obtained from State Pollution Control Board,Govt.of West Bengal.Forward trajectory analysis has been done through HYSPLIT(Hybrid Single Particle Lagrangian Integrated Trajectory)model to find the path and direction of air particles.The result showed that the various meteorological or environmental factors(such as temperature,relative humidity,wind,wind speed,pressure and gusty wind)and geographical location regulate the spatiotemporal variation of PM_(10) and PM_(2.5).These factors like high temperature with relative humidity and strong wind influence to disperse the particulate matters from north to south direction from city to outside during summer in Kolkata metropolitan city.During summer(both pre and lockdown years),the height of particles is extended up to 1000 m owing to active atmospheric ventilation whereas in winter it is confined within 100 m.The HYSPLIT model clearly specified that the particles dispersed from south,south-west to north and north east direction due to strong wind.The constant magnification of PM_(10) and PM_(2.5) in the lower atmosphere leads to greater frequency of COVID-19 infections and deaths.In Kolkata,the one of the crucial reasons of high infection and deaths(COVID-19)is co-morbidity of people.

摘要： The shape of fruit apex is critical to appearance quality in cucumber(Cucumis sativus L.),of which the genetic basis was poorly understood,and the use of marker-assisted breeding for fruit apex improvement is not available yet.In this study,the variation of fruit apex in different cucumber ecotypes was evaluated by fruit apex angle(variation coefficient from 7.1%to 15.7%)and fruit apex index(variation coefficient from 8.8%to 22.6%).Fruit apex associated QTLs were mapped by using 145 F_(2:3) families and 155 F_(2:6) population that were derived from the cross of different ecotype cucumbers.Phenotyping of the mapping populations were conducted in four experiments in 2 years.Four majoreffect QTLs,Bfal4.1,Bfai4.1,Bfad6.1 and Bfai6.1 were consistently and reliably detected across two environments which could explain 11.6%-33.6%phenotypic variations(R^(2))in the F_(2:3) families.Three major-effect QTLs,Ofai4.1(R^(2)=13.4%-15.5%),Ofal4.1(R^(2)=10.7%-12.8%),and Ofad6.1(R^(2)=11.6%-12.4%)were stably detected in the F_(2:6) population in two experiments.Bfai4.1,Bfal4.1,Ofai4.1 and Ofal4.1 were integrated to be consensus QTL fa4.1,within which 11 candidate genes were predicted.Bfai6.1 and Bfad6.1 were integrated to be consensus QTL fa6.1.QTL interaction analysis showed that Bfai6.1 has epistatic effect with Bfai4.1.This study revealed two reliable major-effect fruit apex related QTLs across multi-genetic backgrounds and environments in cucumber.The possible candidate genes regulating the shape of fruit apex,and the relationship between cell division and fruit apex morphogenesis were discussed.

摘要： In this paper, we analyzed diurnal and annual seasonal variations of solar wind parameters such as interplanetary magnetic field (IMF), proton density (N), solar wind speed (V) and solar wind dynamic pressure (Pdym), during the solar cycles 23 and 24. Our study shows that strong geomagnetic disturbances are observed at the equinoxes during both solar cycles. The highest proton densities are observed at solstices during both solar cycles. The greatest solar wind speeds are observed at the equinoxes of solar cycle 23 and at the solstices of solar cycle 24. The highest solar wind dynamic pressures are observed at the solstices of both solar cycles. We also observed an asymmetrical evolution of the seasonal diurnal values of the solar wind parameters during the two cycles, except for the proton density. Our investigations also highlight the fact that the seasonal diurnal values of the solar wind parameters are significant at solar cycle 23 compared to solar cycle 24 characterized by a global weak in solar plasma conditions since the deep minimum that followed the solar cycle 23 leading to an absence of a persistent polar coronal hole. The drop observed in polar field and solar winds parameters during solar cycle 24 is reproduced on seasons (solstices and equinoxes). The solar cycle 23 and 24 appear to be two magnetically opposite solar cycles regardless the time scales.

摘要： In 1922,“Alice’s Adventures in Wonderland”was translated and introduced by Zhao Yuanren to China.In the 1930s and 1940s,a series of Chinese-style“Alice”stories appeared.Writers borrowed from the plot structure and character images of“Alice’s Adventures in Wonderland”,making it a work rich in Chinese national language and culture.This article uses the documentary method and comparative research to study the Chinese-style“Alice”stories,and believes that these stories consciously convey new literary concepts,shape children in the new era,and become a part of modern Chinese children’s literature.

摘要： To select elite materials,the growth traits of 32 Betula platyphylla clones at three separated northern sites in Northeast China were investigated and analyzed.The results showed that there were significant differences among all variation sources in the different investigated traits(P<0.01).Except for the carbon contents,all the coeffi-cients of phenotypic variation of the other investigated traits were higher than 10%.The repeatability of different traits ranged from 0.760 to 0.998.Correlation analysis showed that tree height were significantly correlated with diameter at breast height,but neither was significantly correlated with leaf traits nor element contents.Additive main effects and multiplicative interaction analysis showed that genotype,environment and genotype×environment interactions were significantly different in diameter at breast height,which indicated that environment had a significant effect on genotype.Comprehensive assessment results showed that three clones with high and stable diameters at breast height were selected,and the genetic gains of diameter at breast height on sites Maoershan,Qingan,and Yongji were 21.24%,20.58%,and 38.65%,respectively.The results could provide a theoretical basis for elite clone selection in B.platyphylla and other broad leaved species.

摘要： Porcine reproductive and respiratory syndrome virus(PRRSV) has been mutating and evolving constantly since its emergence in the1980s, which has brought inestimable economic losses to the global swine industry. The virus has two genotypes, of which genotype 1 PRRSV(PRRSV 1) first broke out in Germany and mainly prevailed in Europe, which can be clustered into four subtypes based on the ORF5 sequence. Al-though few cases of PRRSV 1 have been reported in China, the prevention and control of PRRSV should not be ignored. The origin of PRRSV, ge-netic evolution and pathogenicity of PRRSV 1 were retrospectively analyzed, in order to provide valuable evidences for molecular epidemiology and immune prevention and control of PRRSV 1.

摘要： [Objectives]To study the temporal and spatial variation of SOC content in cultivated land in black soil region in Liaoning Province.[Methods]Through the evaluation and analysis of the research data of this project and the data of the second national soil census,and using GIS technology,this paper studied the temporal and spatial variation characteristics of SOC in the black soil region of Liaoning Province,and provided a basis for improving cultivated land carbon storage and soil organic matter content.[Results]Since 1980,the SOC content in cultivated land in the black soil region in Liaoning Province has generally declined,and the spatial distribution difference has gradually decreased.From 1980 to 2018,the homogeneity of SOC distribution weakened,and the variation in a small range strengthened.The SOC content generally showed the characteristics of increase and decrease,and the changes in the area were scattered.[Conclusions]This study is of great significance to the sustainable utilization of land resources.

摘要： The aim of this paper is to reveal the results of a sociolinguistic investigation in the holy city of Mecca,Saudi Arabia.The researcher examined the variation and change in the speech of Ghamdi migrants who migrated from the South-Western region,Al-Baḥa,of Saudi Arabia to the Western part,Mecca.This migration brought Ghamdis into everyday contact with Meccan.Meccan and Ghamdi dialects are mutually intelligible,however,the linguistic differences between them are enormous.They are different syntactically,morphologically,phonologically,semantically,and lexically.Therefore,it has been expected that sort of variation and change will occur in this contact setting.The study discussed the change in the usage of the interdentals(θ),(■),and(■)in relation to three social variables,namely,education,age,and gender.The researcher attempted to answer the following questions:Is there an age effect on the speech of Ghamdi migrants in Mecca?Does gender play a role in the changes that occur in the speech of Ghamdis?Does the level of education have any impact on the Ghamdi linguistic behaviour?And Is there any relation between language change and level of Ghamdis’education?The results revealed that Ghamdi migrants maintained their heritage variants[θ],[■],and[■]at the expense of the Meccan variants[t],[d],and[■].

摘要： throughout the development of 20th-century art, Eastern and Western art concepts has undergone tremendous change and transition；this era has produced many masters, but also created a lot of genres.Whether the Chinese landscape painting, or the oil rich west, a number of groups have achieved excellence inthe field of artistic talent. This paper focus on the big art concepts in the lead, through the comparison of artconcept between Monet and Binhong Huang, to collect necessary through the intrinsic link between them, thistime paragraph to analysis the relationship between Eastern and Western painting.

摘要： throughout the development of 20th-century art, Eastern and Western art concepts has undergone tremendous change and transition；this era has produced many masters, but also created a lot of genres.Whether the Chinese landscape painting, or the oil rich west, a number of groups have achieved excellence inthe field of artistic talent. This paper focus on the big art concepts in the lead, through the comparison of artconcept between Monet and Binhong Huang, to collect necessary through the intrinsic link between them, thistime paragraph to analysis the relationship between Eastern and Western painting.

摘要： throughout the development of 20th-century art, Eastern and Western art concepts has undergone tremendous change and transition；this era has produced many masters, but also created a lot of genres.Whether the Chinese landscape painting, or the oil rich west, a number of groups have achieved excellence inthe field of artistic talent. This paper focus on the big art concepts in the lead, through the comparison of artconcept between Monet and Binhong Huang, to collect necessary through the intrinsic link between them, thistime paragraph to analysis the relationship between Eastern and Western painting.