This study used the synthetic running correlation coefficient calculation method to calculate the running correlation coefficients between the daily sea ice concentration(SIC) and sea surface air temperature(SSAT) in ...This study used the synthetic running correlation coefficient calculation method to calculate the running correlation coefficients between the daily sea ice concentration(SIC) and sea surface air temperature(SSAT) in the Beaufort-Chukchi-East Siberian-Laptev Sea(BCEL Sea), Kara Sea and southern Chukchi Sea, with an aim to understand and measure the seasonally occurring changes in the Arctic climate system. The similarities and differences among these three regions were also discussed. There are periods in spring and autumn when the changes in SIC and SSAT are not synchronized, which is a result of the seasonally occurring variation in the climate system. These periods are referred to as transition periods. Spring transition periods can be found in all three regions, and the start and end dates of these periods have advancing trends. The multiyear average duration of the spring transition periods in the BCEL Sea, Kara Sea and southern Chukchi Sea is 74 days, 57 days and 34 days, respectively. In autumn, transition periods exist in only the southern Chukchi Sea, with a multiyear average duration of only 16 days. Moreover, in the Kara Sea, positive correlation events can be found in some years, which are caused by weather time scale processes.展开更多
Background The dairy cow’s postpartum period is characterized by dramatic physiological changes,therefore imposing severe challenges on the animal for maintaining health and milk output.The dynamics of the ruminal mi...Background The dairy cow’s postpartum period is characterized by dramatic physiological changes,therefore imposing severe challenges on the animal for maintaining health and milk output.The dynamics of the ruminal microbiota are also tremendous and may play a crucial role in lactation launch.We aim to investigate the potential benefits of early microbial intervention by fresh rumen microbiota transplantation(RMT)and sterile RMT in postpartum dairy cows.Twelve fistulated peak-lactation dairy cows were selected to be the donors for rumen fluid collection.Thirty postpartum cows were divided into 3 groups as the transplantation receptors respectively receiving 10 L fresh rumen fluid(FR),10 L sterile rumen fluid(SR),or 10 L saline(CON)during 3 d after calving.Results Production performance,plasma indices,plasma lipidome,ruminal microbiome,and liver transcriptome were recorded.After fresh and sterile RMT,we found that the molar proportion of propionic acid was increased on d 7 in the FR and SR groups and the bacterial composition was also significantly changed when compared with the CON group.A similarity analysis showed that the similarities between the CON group and FR or SR group on d 7 were 48.40%or 47.85%,whereas the similarities between microbiota on d 7 and 21 in the FR and SR groups were 68.34%or 66.85%.Dry matter intake and feed efficiency were not affected by treatments.Plasmaβ-hydroxybutyrate concentration in the FR group was decreased and significantly different lipids mainly included phosphatidylcholine and lysophosphatidylcholine containing polyunsaturated fatty acids.Hepatic transcriptomics analysis indicated acutephase response pathways were upregulated in the SR group.Conclusions Our study suggests that RMT can shorten the transition process of the ruminal microbiota of postpartum dairy cows with no benefit on dry matter intake or feed efficiency.Inoculation with rumen fluid may not be a useful approach to promote the recovery of postpartum dairy cows.展开更多
The concentration of 39 trace elements in coal from the late Permian taken from the eastern Yunnan-western Guizhou region was determined using inductively coupled plasma mass spectrometry. It was found that the mean c...The concentration of 39 trace elements in coal from the late Permian taken from the eastern Yunnan-western Guizhou region was determined using inductively coupled plasma mass spectrometry. It was found that the mean content of Ti, V, Cr, Mo, Co, Ni, Y, and Zr is higher than the national average. The occurrence of Mn, Ni, and Co in the different coalfields is distinctly different. Most of the enriched transition metal elements exist mainly as inorganic minerals. In the Zhina coalfield, Co, Ni, and Nb are primarily associated with sulfur. Mn, Cs, and Mo are mostly sulfides. Almost all Co was organic and a significant part of the Ni is also organic in the Liupanshui coalfield. Cs, Co, and Ni are related to sulfur in the coal taken from eastern Yunnan. Carbonate is the main form of Mn in the coal from eastern Yunnan and the Liupanshui coalfield. Ti is the oxide in the coal samples where Ti is enriched. Zr is in the form of zircon in the samples where Zr is enriched. The situation for most of the transition metal elements is consistent with terrestrial genesis. Coal seams are universally influenced by the sea. The strongly seawater effected peat bog with a reductive and alkaline environment favors the relative enrichment of Mn. A reducing environment is conducive to transition metal element enrichment.展开更多
Sister Carrie and Dwelling depict two heroines who share similarities in many aspects. They all live in the social transitional period and suffer a lot. This paper will make a comparison about the two ladies' trag...Sister Carrie and Dwelling depict two heroines who share similarities in many aspects. They all live in the social transitional period and suffer a lot. This paper will make a comparison about the two ladies' tragic fates and aims to investigate the impact on females brought about by the social transition.展开更多
Based on the definition of the concept of city growth, the paper mainly discussed the factors which impact the growth of Chinese cities in the transitional period by selecting the proportion of city construction land ...Based on the definition of the concept of city growth, the paper mainly discussed the factors which impact the growth of Chinese cities in the transitional period by selecting the proportion of city construction land area to the area of the city X1(%), green coverage ratio of the built up area X2(%), the ratio of personnel involved in the secondary industry X3(%), the GDP per capita X4(×104)and other 43 indicators, by relying on the relevant data from China Urban Statistical Yearbook(2008), applying SPSS statistical software and by applying the Factor Analysis and Regression Analysis. The results show that the factors which affect the city growth have four major groups, namely economic and institutional factors, location factors, environmental factors and social cultural services and functions. Among the factors which affect Chinese city growth, the general budgetary expenditures and the general budgetary revenues of local public finance are the most important factors. The general budgetary expenditures of local finance, the general budgetary revenues, the lands of urban construction and other 12 factors obtained by gradually excluding method can be used to present the coefficient of city growth.展开更多
We investigate the topological phase transition and the enhanced topological effect in a cavity optomechanical system with periodical modulation.By calculating the steady-state equations of the system,the steady-state...We investigate the topological phase transition and the enhanced topological effect in a cavity optomechanical system with periodical modulation.By calculating the steady-state equations of the system,the steady-state conditions of cavity fields and the restricted conditions of effective optomechanical couplings are demonstrated.It is found that the cavity optomechanical system can be modulated to different topological Su–Schrieffer–Heeger(SSH)phases via designing the optomechanical couplings legitimately.Meanwhile,combining the effective optomechanical couplings and the probability distributions of gap states,we reveal the topological phase transition between trivial SSH phase and nontrivial SSH phase via adjusting the decay rates of cavity fields.Moreover,we find that the enhanced topological effect of gap states can be achieved by enlarging the size of system and adjusting the decay rates of cavity fields.展开更多
Floquet dynamical quantum phase transitions(DQPTs),which are nonanalytic phenomena recuring periodically in time-periodic driven quantum many-body systems,have been widely studied in recent years.In this article,the F...Floquet dynamical quantum phase transitions(DQPTs),which are nonanalytic phenomena recuring periodically in time-periodic driven quantum many-body systems,have been widely studied in recent years.In this article,the Floquet DQPTs in transverse XY spin chains under the modulation ofδ-function periodic kickings are investigated.We analytically solve the system,and by considering the eigenstate as well as the ground state as the initial state of the Floquet dynamics,we study the corresponding multiple Floquet DQPTs emerged in the micromotion with different kicking moments.The rate function of return amplitude,the Pancharatnam geometric phase and the dynamical topological order parameter are calculated,which consistently verify the emergence of Floquet DQPTs in the system.展开更多
values occupy an important position in the lives of the people, almost all the joy, happiness, sadness, unfortunately are related with the values. It pervades all aspects of social life, reflects the contradictions an...values occupy an important position in the lives of the people, almost all the joy, happiness, sadness, unfortunately are related with the values. It pervades all aspects of social life, reflects the contradictions and conflicts of the various aspects. While Chinese society is undergoing a transformation of the special period, Social value orientation of instability makes further thought and exploration,in order to get a judgement conform to social development and human interests of social value standard.展开更多
With the establishment of labor market of China, market is playing a more and mare important role in allocation of human resources. However, with the transition of economy in China and industrial upgrading in recent y...With the establishment of labor market of China, market is playing a more and mare important role in allocation of human resources. However, with the transition of economy in China and industrial upgrading in recent years, many labor problems have occurred which do harm to the sustainable development of local economy. The paper researches on the labor market issues of China from the perspective of local labor market regulation. Firstly, it reviews the theories of local labor market regulation. And then the main components of local labor market regulation of China are identified and the evaluation index system is established. The results of analysis of the calculated output show that (1) the local labor market regulation of China has an obvious character of gradient distribution geographically and decreases gradually from east to west; (2) of all the regulations, the regulation of the development of human capital has the most significant impact on local economy currently which is followed by the regulation of labor relation and the regulation of market participation. As to the regulation of social security, it has no Significant impact on the development of local economy.展开更多
Background The interrupted time series(ITS)design is a widely used approach to examine the effects of interventions.However,the classic segmented regression(CSR)method,the most popular statistical technique for analyz...Background The interrupted time series(ITS)design is a widely used approach to examine the effects of interventions.However,the classic segmented regression(CSR)method,the most popular statistical technique for analyzing ITS data,may not be adequate when there is a transitional period between the pre-and post-intervention phases.Methods To address this issue and better capture the distribution patterns of intervention effects during the transition period,we propose using different cumulative distribution functions in the CSR model and developing corresponding optimized segmented regression(OSR)models.This study illustrates the application of OSR models to estimate the long-term impact of a national free delivery service policy intervention in Ethiopia.Results Regardless of the choice of transition length(L)and distribution patterns of intervention effects,the OSR models outperformed the CSR model in terms of mean square error(MSE),indicating the existence of a transition period and the validity of our model’s assumptions.However,the estimates of long-term impacts using OSR models are sensitive to the selection of L,highlighting the importance of reasonable parameter specification.We propose a data-driven approach to select the transition period length to address this issue.Conclusions Overall,our OSR models provide a powerful tool for modeling intervention effects during the transition period,with a superior model fit and more accurate estimates of long-term impacts.Our study highlights the importance of appropriate statistical methods for analyzing ITS data and provides a useful framework for future research.展开更多
Background:In seasonal,pasture-based,dairy production systems,cows must recover from calving and become pregnant within two to 3 months.To achieve this,the uterus must involute and ovulation must occur and continue at...Background:In seasonal,pasture-based,dairy production systems,cows must recover from calving and become pregnant within two to 3 months.To achieve this,the uterus must involute and ovulation must occur and continue at regular intervals.As these processes are affected by the cows’nutritional or metabolic status post-calving,the objective of this study was to evaluate the effect of cow feeding strategies on uterine health,the length of postpartum anestrous interval,and reproductive outcomes.The treatments consisted of two feeding strategies during late-lactation and early dry period(far-off period;starting 4-month pre-calving)and three close-up dry period feeding regimes(1-month pre-calving)in a 2×3 factorial arrangement.We randomly assigned 150 cows to one of two far-off treatments.During late lactation,the herds(n=75 cows per herd)were either control-fed(Controlfed)or over-fed(Overfed)to achieve a low or high body condition score(4-month pre-calving;BCS;~4.25 and^4.75;10-point scale)at cessation of lactation.Within each of these treatments,three feeding levels were applied during the close-up period(1-month pre-calving):~65%(Feed65),~90%(Feed90),or^120%(Feed120)of metabolizable energy(ME)intakes relative to pre-calving requirements.Results:Uterine health improved(i.e.polymorphonucleated(PMN)cells declined)with increased feeding during the close-up period for cows in the Overfed group.The reverse was evident for the Controlfed group with the greatest PMN at the highest intakes during the close-up period.The postpartum anoestrous interval(PPAI)was shorter in cows from the Overfed group when moderately fed(Feed90)during the close-up period;in comparison,the PPAI was shorter in the Controlfed group,when those cows were overfed in the close-up period(Feed120).The cows in the Overfed treatment had greater conception and pregnancy rates if cows had moderate dry matter intakes(Feed90)during the close-up period;these reproductive variables were less under excessive feed intakes(Feed120);yet,close-up dry matter intake had little effect on conception and pregnancy rates for the Controlfed group.Conclusions:The far-off feeding strategies increased early reproductive outcomes at 3 weeks of mating.Additionally,the interaction between far-off and close-up feeding strategies resulted in high six-week pregnancy rate with a slight restriction during the close-up period but only in the far-off Overfed group.Thus,our hypothesis is supported under these conditions.展开更多
The widely-developed,mixed clastic-carbonate succession in the northern Qaidam Basin records the paleo-environment changes under the glacial activity during the Late Paleozoic icehouse period in the context of regiona...The widely-developed,mixed clastic-carbonate succession in the northern Qaidam Basin records the paleo-environment changes under the glacial activity during the Late Paleozoic icehouse period in the context of regional tectonic stability,however,the depositional environment and sequence stratigraphy characteristics of the mixed deposits is rarely reported and still not clear.Combined the latest drilling wells data,we analyzed the sedimentary and stratigraphic characterization of the mixed strata via detailed field outcrops and core observations and thin section microscopic observations and recognized three depositional systems,including progradational coastal system,incised valley system,and carbonate-dominated marine shelf system,and identified four third-order sequences,SQ1,SQ2,SQ3 and SQ4,consisting of LST,TST,and HST.The depositional environment is overall belonged to marine-continental transition context and shifted from marine to continental environment frequently,showing an evolutionary pattern from marine towards terrestrial-marine transition and then back into the marine environment again in the long-term,which was controlled by the regional tectonic subsidence and the high-frequency and large-amplitude sea-level changes due to the Late Paleozoic glacial activity.The result is of significance in understanding the evolution of the Qinghai-Tibet Plateau and the sedimentation-climate response.展开更多
[Objective]The paper was to investigate the mechanism of Bacillus coagulans preparation in improving production performance of laying hens in late period of laying.[Method]A total of 648 individuals of"Jingfen 1&...[Objective]The paper was to investigate the mechanism of Bacillus coagulans preparation in improving production performance of laying hens in late period of laying.[Method]A total of 648 individuals of"Jingfen 1"laying hens(66 weeks of age)in late period of laying were randomly divided into four groups,six replicates each group,and each group had 27 individuals of laying hens.The laying hens in control group were fed with basal diet,and those in experimental groupsⅠ,Ⅱ and Ⅲ were fed with the basal diets added with 3.33×10^6,1×10^7,3.33×10^7 CFU/g B.coagulans,respectively.The pretrial lasted one week,and the formal test lasted eight weeks.[Result]Compared with the control group,the laying rate in group Ⅰ increased significantly,and the feed-gain ratio in experimental group Ⅱ decreased noticeably while the spleen index increased remarkably;the alkaline phosphatase activities and blood calcium content in experimental groups Ⅰ,Ⅱ and Ⅲ increased significantly(P<0.05),while the triglyceride content decreased remarkably(P<0.05);the urea content in experimental groups Ⅰ and Ⅱ decreased obviously(P<0.05).Adding B.coagulans significantly increased the specific activity of amylase,lipase and protease in various intestinal mucosa of small intestine(P<0.05);adding B.coagulans significantly increased the content of follicle-stimulating hormone(FSH)and estradiol(E2),and significantly increased the mRNA expression of follicle stimulating hormone receptor gene(FSHR).[Conclusion]B.coagulans preparation could significantly improve the production performance of laying hens in late period of laying;appropriately enhance the immune capacity of laying hens;improve the serum biochemical indicators;increase the activity of digestive enzymes in the small intestine;and promote the release of gonadal hormone and the mRNA expression of FSHR gene in the ovary.展开更多
[Objective]The paper was to study the effects of xylooligosaccharide(XOS)and probiotics(PRO)and their interaction on the production performance,egg quality and intestinal short-chain fatty acids of laying hens in late...[Objective]The paper was to study the effects of xylooligosaccharide(XOS)and probiotics(PRO)and their interaction on the production performance,egg quality and intestinal short-chain fatty acids of laying hens in late laying period.[Method]A total of 36074-week-old Romain brown laying hens were randomly divided into four groups,six replicates each group and 15 chickens each replicate.The trial lasted 63 d.The laying hens in control group(CON)were fed with basal diet,and those in experimental groups were fed with the basal diets adding with 150 mg/kg XOS(XOS group),100 mg/kg probiotics(PRO group),150 mg/kg XOS+100 mg/kg probiotics(XOS-PRO group).[Result]Compared with the control group,the laying rate,daily egg production,yolk ratio,colonic acetic acid and caecal propionic acid in XOS group increased significantly(P<0.05),and the feed gain ratio decreased remarkably(P<0.05).PRO had no significant effect on the production performance and egg quality of laying hens in late laying period(P>0.05),but significantly increased colonic acetic acid(P<0.05).XOS and PRO had no interaction effect on the production performance,egg quality and intestinal short-chain fatty acids of laying hens in late laying period(P<0.05).[Conclusion]Adding XOS to the diet of laying hens in late laying period could increase the content of short-chain fatty acids in the hindgut of laying hens,and effectively improve the production performance and egg quality of laying hens in late laying period.Adding PRO to the diet did not significantly improve the production performance and egg quality of laying hens,and there was no interaction effect between XOS and PRO.展开更多
The relationship between the evolution of human societies and their living environments has been discussed intensively in recent decades.It is important to understand the patterns and mechanisms of human–environment ...The relationship between the evolution of human societies and their living environments has been discussed intensively in recent decades.It is important to understand the patterns and mechanisms of human–environment interaction and evolution in order to cope with rapidly changing environments in the modern world.We reviewed the results of dating,archaeobotanical,and zooarchaeological studies from 139 prehistoric sites in the Northeast Tibetan Plateau(NETP)and contiguous regions(NETP-CR:i.e.,the Hexi Corridor and western margin of the Chinese Loess Plateau)and compared them with paleoenvironmental records to study variations in spatiotemporal patterns of social development in the area and their relationships with climate and vegetation changes.Our results show that hunter-gatherer groups occupied vast areas of the NETP at low intensities during^15,000–5500 BP(years before present).This was directly related to forest cover and climate change.An increase in temperature and precipitation turnover of vegetation from desert steppe to alpine meadow/subalpine shrub,and recovery of animal population on the Tibetan Plateau created more food resources and space for hunter-gatherers.Millet farmers settled extensively below 2500 m a.s.l.(meters above sea level)in the NETP-CR between^5500 and 3600 BP,and might have coexisted with hunting groups above 2500 m a.s.l.via subsistence exchange.The distribution of human settlements during that period was affected by climate change,with the relatively warm and wet climate promoting the expansion of millet agriculture to the NETP-CR during 5500–4500 BP,while climate deterioration caused humans to retreat to lower altitudes.During 3600–2200 BP,a range of livelihoods emerged in different regions of the NETPCR.This was promoted by early trans-Eurasian exchange and the development of an agro-pastoral economy that utilized cold-tolerant crops and livestock.This eventually promoted the expansion of permanent human settlements to high-altitude areas in the NETP.This study found that human societies adopted various strategies to adapt to the changing living environment throughout late prehistoric times in the NETP-CR.The results provide a long-term perspective on the trajectory of regional socio-environmental co-evolution.展开更多
The goal of this research is to describe and analyze women’s wear in the late Qing Dynasty andearly Republic Period(late 19th c.—early 20th c.),with an emphasis on the daily informal orsemi-formal wear,though some f...The goal of this research is to describe and analyze women’s wear in the late Qing Dynasty andearly Republic Period(late 19th c.—early 20th c.),with an emphasis on the daily informal orsemi-formal wear,though some formal or ceremonial costumes such as wedding dress will also beincluded.This study will use Chinese costumes and textiles from many museums to fill in theblanks left by previous research and to give a more detailed and accurate description.It will alsouse historical documents to find the original names of these items and to illustrate a general conceptof their usage on different occasions.The different categories of women’s wear will be described in the following order:①robes orcoats;②jackets;③waistcoats or vests;④skirts;⑤pants and leggings;⑥shoes and socks;⑦headdresses;and⑧others.Of every category,the textiles,decoration,cut,form,style,colourand motif will be discussed.The way in which these items were combined will also be discussed.The comparison between women’s wear and men’s wear,women’s and children’s informal andformal dress will be given.Here are some tentative conclusions.First,the Manchu and Han style coexisted and mixedwith each other and were worn by both Manchu and Han women.Second,the basic silhouettesand cuts were relatively stable and conventional,while the decorations and details(openings,fasten-ings,pleats,vents,collars and hemlines)were different.The former represented accepted socialstandards while the latter could be a matter of personal taste.Third,women’s wear in that periodwere highly stylized,miscellaneous,elaborate,detailed,multicolored and multi-thematic.展开更多
Precessing ball solitons (PBS) in a ferromagnet during the first order phase transition is induced by a magnetic field directed along the axis of anisotropy, while the action of the periodic field perpendicular to the...Precessing ball solitons (PBS) in a ferromagnet during the first order phase transition is induced by a magnetic field directed along the axis of anisotropy, while the action of the periodic field perpendicular to the main magnetic field has been analyzed. Under these conditions, the characteristics of arising equilibrium PBS are uniquely determined by the frequency of the periodic field, but the solitons with other frequencies are impossible. For such structure, the entropy increase connected with dissipation is compensated by the decrease of the entropy due to the external periodic field. It is shown that the equilibrium PBS are essentially the “self-organizing systems” that can arise spotaneously in a metastable state of ferromagnet.展开更多
Floquet engineering has attracted considerable attention as a promising approach for tuning topological phase transitions.We investigate the effects of high-frequency time-periodic driving in a four-dimensional(4D)top...Floquet engineering has attracted considerable attention as a promising approach for tuning topological phase transitions.We investigate the effects of high-frequency time-periodic driving in a four-dimensional(4D)topological insulator,focusing on topological phase transitions at the off-resonant quasienergy gap.The 4D topological insulator hosts gapless three-dimensional boundary states,characterized by the second Chern number C_(2).We demonstrate that the second Chern number of 4D topological insulators can be modulated by tuning the amplitude of time-periodic driving.This includes transitions from a topological phase with C_(2)=±3 to another topological phase with C_(2)=±1,or to a topological phase with an even second Chern number C_(2)=±2,which is absent in the 4D static system.Finally,the approximation theory in the high-frequency limit further confirms the numerical conclusions.展开更多
Objective To investigate the therapeutic efficacy of castration with 125 I brachtherapy in middle and late stage prostate cancer. Methods Sixty-six patients with prostate cancer from 2004 to 2009 were analyzed,40 were...Objective To investigate the therapeutic efficacy of castration with 125 I brachtherapy in middle and late stage prostate cancer. Methods Sixty-six patients with prostate cancer from 2004 to 2009 were analyzed,40 were at clinical stage C and 26 were at clinical stage D,展开更多
The study aims to solve the problems of late transplanting rice with differ- ent seedling ages at the lower reaches of Yangtze River. We selected six varieties of different thermal and photo-response characteristics a...The study aims to solve the problems of late transplanting rice with differ- ent seedling ages at the lower reaches of Yangtze River. We selected six varieties of different thermal and photo-response characteristics as the test material to study the effect of different seedling ages on growth and yield of rice. The results showed that growing period of thermal-response rice was delayed by long seedling age, but less affected by the impact of photo-response rice; the yield of later thermal-re- sponse varieties with 25 days and 30 days seedling ages was significantly reduced. In contrast, the yield of early thermal-response varieties and later photo-response varieties were significantly reduced with 30 days seedling age. The optimal trans- planting seedling age was 15 days of thermal-response rice, while photo-response rice was 20 days. The thermal-response rice should be selected as early maturing varieties, while the photo-response rice could be selected as late maturing varieties for high yield.展开更多
基金supported by the National Major Science Project of China for Global Change Research (No. 2015CB953900)the National Natural Science Foundation of China (No. 41330960)
文摘This study used the synthetic running correlation coefficient calculation method to calculate the running correlation coefficients between the daily sea ice concentration(SIC) and sea surface air temperature(SSAT) in the Beaufort-Chukchi-East Siberian-Laptev Sea(BCEL Sea), Kara Sea and southern Chukchi Sea, with an aim to understand and measure the seasonally occurring changes in the Arctic climate system. The similarities and differences among these three regions were also discussed. There are periods in spring and autumn when the changes in SIC and SSAT are not synchronized, which is a result of the seasonally occurring variation in the climate system. These periods are referred to as transition periods. Spring transition periods can be found in all three regions, and the start and end dates of these periods have advancing trends. The multiyear average duration of the spring transition periods in the BCEL Sea, Kara Sea and southern Chukchi Sea is 74 days, 57 days and 34 days, respectively. In autumn, transition periods exist in only the southern Chukchi Sea, with a multiyear average duration of only 16 days. Moreover, in the Kara Sea, positive correlation events can be found in some years, which are caused by weather time scale processes.
基金supported by the National Natural Science Foundation of China(32130100).
文摘Background The dairy cow’s postpartum period is characterized by dramatic physiological changes,therefore imposing severe challenges on the animal for maintaining health and milk output.The dynamics of the ruminal microbiota are also tremendous and may play a crucial role in lactation launch.We aim to investigate the potential benefits of early microbial intervention by fresh rumen microbiota transplantation(RMT)and sterile RMT in postpartum dairy cows.Twelve fistulated peak-lactation dairy cows were selected to be the donors for rumen fluid collection.Thirty postpartum cows were divided into 3 groups as the transplantation receptors respectively receiving 10 L fresh rumen fluid(FR),10 L sterile rumen fluid(SR),or 10 L saline(CON)during 3 d after calving.Results Production performance,plasma indices,plasma lipidome,ruminal microbiome,and liver transcriptome were recorded.After fresh and sterile RMT,we found that the molar proportion of propionic acid was increased on d 7 in the FR and SR groups and the bacterial composition was also significantly changed when compared with the CON group.A similarity analysis showed that the similarities between the CON group and FR or SR group on d 7 were 48.40%or 47.85%,whereas the similarities between microbiota on d 7 and 21 in the FR and SR groups were 68.34%or 66.85%.Dry matter intake and feed efficiency were not affected by treatments.Plasmaβ-hydroxybutyrate concentration in the FR group was decreased and significantly different lipids mainly included phosphatidylcholine and lysophosphatidylcholine containing polyunsaturated fatty acids.Hepatic transcriptomics analysis indicated acutephase response pathways were upregulated in the SR group.Conclusions Our study suggests that RMT can shorten the transition process of the ruminal microbiota of postpartum dairy cows with no benefit on dry matter intake or feed efficiency.Inoculation with rumen fluid may not be a useful approach to promote the recovery of postpartum dairy cows.
基金financially supported by the National Natural Science Foundation of China (No. 40730422)
文摘The concentration of 39 trace elements in coal from the late Permian taken from the eastern Yunnan-western Guizhou region was determined using inductively coupled plasma mass spectrometry. It was found that the mean content of Ti, V, Cr, Mo, Co, Ni, Y, and Zr is higher than the national average. The occurrence of Mn, Ni, and Co in the different coalfields is distinctly different. Most of the enriched transition metal elements exist mainly as inorganic minerals. In the Zhina coalfield, Co, Ni, and Nb are primarily associated with sulfur. Mn, Cs, and Mo are mostly sulfides. Almost all Co was organic and a significant part of the Ni is also organic in the Liupanshui coalfield. Cs, Co, and Ni are related to sulfur in the coal taken from eastern Yunnan. Carbonate is the main form of Mn in the coal from eastern Yunnan and the Liupanshui coalfield. Ti is the oxide in the coal samples where Ti is enriched. Zr is in the form of zircon in the samples where Zr is enriched. The situation for most of the transition metal elements is consistent with terrestrial genesis. Coal seams are universally influenced by the sea. The strongly seawater effected peat bog with a reductive and alkaline environment favors the relative enrichment of Mn. A reducing environment is conducive to transition metal element enrichment.
文摘Sister Carrie and Dwelling depict two heroines who share similarities in many aspects. They all live in the social transitional period and suffer a lot. This paper will make a comparison about the two ladies' tragic fates and aims to investigate the impact on females brought about by the social transition.
基金Supported by National Natural Science Foundation of China(40771064)Plan for Person with ability of Chinese Ministry of Education in 21 Century& Lanzhou University Foundation for Personwith Ability
文摘Based on the definition of the concept of city growth, the paper mainly discussed the factors which impact the growth of Chinese cities in the transitional period by selecting the proportion of city construction land area to the area of the city X1(%), green coverage ratio of the built up area X2(%), the ratio of personnel involved in the secondary industry X3(%), the GDP per capita X4(×104)and other 43 indicators, by relying on the relevant data from China Urban Statistical Yearbook(2008), applying SPSS statistical software and by applying the Factor Analysis and Regression Analysis. The results show that the factors which affect the city growth have four major groups, namely economic and institutional factors, location factors, environmental factors and social cultural services and functions. Among the factors which affect Chinese city growth, the general budgetary expenditures and the general budgetary revenues of local public finance are the most important factors. The general budgetary expenditures of local finance, the general budgetary revenues, the lands of urban construction and other 12 factors obtained by gradually excluding method can be used to present the coefficient of city growth.
基金the National Natural Science Foundation of China(Grant Nos.61822114,12074330,and 62071412)。
文摘We investigate the topological phase transition and the enhanced topological effect in a cavity optomechanical system with periodical modulation.By calculating the steady-state equations of the system,the steady-state conditions of cavity fields and the restricted conditions of effective optomechanical couplings are demonstrated.It is found that the cavity optomechanical system can be modulated to different topological Su–Schrieffer–Heeger(SSH)phases via designing the optomechanical couplings legitimately.Meanwhile,combining the effective optomechanical couplings and the probability distributions of gap states,we reveal the topological phase transition between trivial SSH phase and nontrivial SSH phase via adjusting the decay rates of cavity fields.Moreover,we find that the enhanced topological effect of gap states can be achieved by enlarging the size of system and adjusting the decay rates of cavity fields.
基金supported by the National Natural Science Foundation of China(Grant No.11475037)the Fundamental Research Funds for the Central Universities(Grant No.DUT19LK38)。
文摘Floquet dynamical quantum phase transitions(DQPTs),which are nonanalytic phenomena recuring periodically in time-periodic driven quantum many-body systems,have been widely studied in recent years.In this article,the Floquet DQPTs in transverse XY spin chains under the modulation ofδ-function periodic kickings are investigated.We analytically solve the system,and by considering the eigenstate as well as the ground state as the initial state of the Floquet dynamics,we study the corresponding multiple Floquet DQPTs emerged in the micromotion with different kicking moments.The rate function of return amplitude,the Pancharatnam geometric phase and the dynamical topological order parameter are calculated,which consistently verify the emergence of Floquet DQPTs in the system.
文摘values occupy an important position in the lives of the people, almost all the joy, happiness, sadness, unfortunately are related with the values. It pervades all aspects of social life, reflects the contradictions and conflicts of the various aspects. While Chinese society is undergoing a transformation of the special period, Social value orientation of instability makes further thought and exploration,in order to get a judgement conform to social development and human interests of social value standard.
基金supported by Knowledge Innovation Program of The Chinese Academy of Sciences (Grant No. O7Q70100AD).
文摘With the establishment of labor market of China, market is playing a more and mare important role in allocation of human resources. However, with the transition of economy in China and industrial upgrading in recent years, many labor problems have occurred which do harm to the sustainable development of local economy. The paper researches on the labor market issues of China from the perspective of local labor market regulation. Firstly, it reviews the theories of local labor market regulation. And then the main components of local labor market regulation of China are identified and the evaluation index system is established. The results of analysis of the calculated output show that (1) the local labor market regulation of China has an obvious character of gradient distribution geographically and decreases gradually from east to west; (2) of all the regulations, the regulation of the development of human capital has the most significant impact on local economy currently which is followed by the regulation of labor relation and the regulation of market participation. As to the regulation of social security, it has no Significant impact on the development of local economy.
基金supported by the National Natural Science Foundation of China(72074229)。
文摘Background The interrupted time series(ITS)design is a widely used approach to examine the effects of interventions.However,the classic segmented regression(CSR)method,the most popular statistical technique for analyzing ITS data,may not be adequate when there is a transitional period between the pre-and post-intervention phases.Methods To address this issue and better capture the distribution patterns of intervention effects during the transition period,we propose using different cumulative distribution functions in the CSR model and developing corresponding optimized segmented regression(OSR)models.This study illustrates the application of OSR models to estimate the long-term impact of a national free delivery service policy intervention in Ethiopia.Results Regardless of the choice of transition length(L)and distribution patterns of intervention effects,the OSR models outperformed the CSR model in terms of mean square error(MSE),indicating the existence of a transition period and the validity of our model’s assumptions.However,the estimates of long-term impacts using OSR models are sensitive to the selection of L,highlighting the importance of reasonable parameter specification.We propose a data-driven approach to select the transition period length to address this issue.Conclusions Overall,our OSR models provide a powerful tool for modeling intervention effects during the transition period,with a superior model fit and more accurate estimates of long-term impacts.Our study highlights the importance of appropriate statistical methods for analyzing ITS data and provides a useful framework for future research.
基金supported by New Zealand dairy farmers through DairyNZ Inc.(RD1403)the Ministry of Business,Innovation,and Employment(DRCX1201).
文摘Background:In seasonal,pasture-based,dairy production systems,cows must recover from calving and become pregnant within two to 3 months.To achieve this,the uterus must involute and ovulation must occur and continue at regular intervals.As these processes are affected by the cows’nutritional or metabolic status post-calving,the objective of this study was to evaluate the effect of cow feeding strategies on uterine health,the length of postpartum anestrous interval,and reproductive outcomes.The treatments consisted of two feeding strategies during late-lactation and early dry period(far-off period;starting 4-month pre-calving)and three close-up dry period feeding regimes(1-month pre-calving)in a 2×3 factorial arrangement.We randomly assigned 150 cows to one of two far-off treatments.During late lactation,the herds(n=75 cows per herd)were either control-fed(Controlfed)or over-fed(Overfed)to achieve a low or high body condition score(4-month pre-calving;BCS;~4.25 and^4.75;10-point scale)at cessation of lactation.Within each of these treatments,three feeding levels were applied during the close-up period(1-month pre-calving):~65%(Feed65),~90%(Feed90),or^120%(Feed120)of metabolizable energy(ME)intakes relative to pre-calving requirements.Results:Uterine health improved(i.e.polymorphonucleated(PMN)cells declined)with increased feeding during the close-up period for cows in the Overfed group.The reverse was evident for the Controlfed group with the greatest PMN at the highest intakes during the close-up period.The postpartum anoestrous interval(PPAI)was shorter in cows from the Overfed group when moderately fed(Feed90)during the close-up period;in comparison,the PPAI was shorter in the Controlfed group,when those cows were overfed in the close-up period(Feed120).The cows in the Overfed treatment had greater conception and pregnancy rates if cows had moderate dry matter intakes(Feed90)during the close-up period;these reproductive variables were less under excessive feed intakes(Feed120);yet,close-up dry matter intake had little effect on conception and pregnancy rates for the Controlfed group.Conclusions:The far-off feeding strategies increased early reproductive outcomes at 3 weeks of mating.Additionally,the interaction between far-off and close-up feeding strategies resulted in high six-week pregnancy rate with a slight restriction during the close-up period but only in the far-off Overfed group.Thus,our hypothesis is supported under these conditions.
基金This work was supported by the National Natural Science Foundation of China(41702124,41772272)the China Geological Survey Program(DD20190094).
文摘The widely-developed,mixed clastic-carbonate succession in the northern Qaidam Basin records the paleo-environment changes under the glacial activity during the Late Paleozoic icehouse period in the context of regional tectonic stability,however,the depositional environment and sequence stratigraphy characteristics of the mixed deposits is rarely reported and still not clear.Combined the latest drilling wells data,we analyzed the sedimentary and stratigraphic characterization of the mixed strata via detailed field outcrops and core observations and thin section microscopic observations and recognized three depositional systems,including progradational coastal system,incised valley system,and carbonate-dominated marine shelf system,and identified four third-order sequences,SQ1,SQ2,SQ3 and SQ4,consisting of LST,TST,and HST.The depositional environment is overall belonged to marine-continental transition context and shifted from marine to continental environment frequently,showing an evolutionary pattern from marine towards terrestrial-marine transition and then back into the marine environment again in the long-term,which was controlled by the regional tectonic subsidence and the high-frequency and large-amplitude sea-level changes due to the Late Paleozoic glacial activity.The result is of significance in understanding the evolution of the Qinghai-Tibet Plateau and the sedimentation-climate response.
文摘[Objective]The paper was to investigate the mechanism of Bacillus coagulans preparation in improving production performance of laying hens in late period of laying.[Method]A total of 648 individuals of"Jingfen 1"laying hens(66 weeks of age)in late period of laying were randomly divided into four groups,six replicates each group,and each group had 27 individuals of laying hens.The laying hens in control group were fed with basal diet,and those in experimental groupsⅠ,Ⅱ and Ⅲ were fed with the basal diets added with 3.33×10^6,1×10^7,3.33×10^7 CFU/g B.coagulans,respectively.The pretrial lasted one week,and the formal test lasted eight weeks.[Result]Compared with the control group,the laying rate in group Ⅰ increased significantly,and the feed-gain ratio in experimental group Ⅱ decreased noticeably while the spleen index increased remarkably;the alkaline phosphatase activities and blood calcium content in experimental groups Ⅰ,Ⅱ and Ⅲ increased significantly(P<0.05),while the triglyceride content decreased remarkably(P<0.05);the urea content in experimental groups Ⅰ and Ⅱ decreased obviously(P<0.05).Adding B.coagulans significantly increased the specific activity of amylase,lipase and protease in various intestinal mucosa of small intestine(P<0.05);adding B.coagulans significantly increased the content of follicle-stimulating hormone(FSH)and estradiol(E2),and significantly increased the mRNA expression of follicle stimulating hormone receptor gene(FSHR).[Conclusion]B.coagulans preparation could significantly improve the production performance of laying hens in late period of laying;appropriately enhance the immune capacity of laying hens;improve the serum biochemical indicators;increase the activity of digestive enzymes in the small intestine;and promote the release of gonadal hormone and the mRNA expression of FSHR gene in the ovary.
文摘[Objective]The paper was to study the effects of xylooligosaccharide(XOS)and probiotics(PRO)and their interaction on the production performance,egg quality and intestinal short-chain fatty acids of laying hens in late laying period.[Method]A total of 36074-week-old Romain brown laying hens were randomly divided into four groups,six replicates each group and 15 chickens each replicate.The trial lasted 63 d.The laying hens in control group(CON)were fed with basal diet,and those in experimental groups were fed with the basal diets adding with 150 mg/kg XOS(XOS group),100 mg/kg probiotics(PRO group),150 mg/kg XOS+100 mg/kg probiotics(XOS-PRO group).[Result]Compared with the control group,the laying rate,daily egg production,yolk ratio,colonic acetic acid and caecal propionic acid in XOS group increased significantly(P<0.05),and the feed gain ratio decreased remarkably(P<0.05).PRO had no significant effect on the production performance and egg quality of laying hens in late laying period(P>0.05),but significantly increased colonic acetic acid(P<0.05).XOS and PRO had no interaction effect on the production performance,egg quality and intestinal short-chain fatty acids of laying hens in late laying period(P<0.05).[Conclusion]Adding XOS to the diet of laying hens in late laying period could increase the content of short-chain fatty acids in the hindgut of laying hens,and effectively improve the production performance and egg quality of laying hens in late laying period.Adding PRO to the diet did not significantly improve the production performance and egg quality of laying hens,and there was no interaction effect between XOS and PRO.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDA20040101)the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(2019QZKK0601)the National Natural Science Foundation of China(41825001,41671077).
文摘The relationship between the evolution of human societies and their living environments has been discussed intensively in recent decades.It is important to understand the patterns and mechanisms of human–environment interaction and evolution in order to cope with rapidly changing environments in the modern world.We reviewed the results of dating,archaeobotanical,and zooarchaeological studies from 139 prehistoric sites in the Northeast Tibetan Plateau(NETP)and contiguous regions(NETP-CR:i.e.,the Hexi Corridor and western margin of the Chinese Loess Plateau)and compared them with paleoenvironmental records to study variations in spatiotemporal patterns of social development in the area and their relationships with climate and vegetation changes.Our results show that hunter-gatherer groups occupied vast areas of the NETP at low intensities during^15,000–5500 BP(years before present).This was directly related to forest cover and climate change.An increase in temperature and precipitation turnover of vegetation from desert steppe to alpine meadow/subalpine shrub,and recovery of animal population on the Tibetan Plateau created more food resources and space for hunter-gatherers.Millet farmers settled extensively below 2500 m a.s.l.(meters above sea level)in the NETP-CR between^5500 and 3600 BP,and might have coexisted with hunting groups above 2500 m a.s.l.via subsistence exchange.The distribution of human settlements during that period was affected by climate change,with the relatively warm and wet climate promoting the expansion of millet agriculture to the NETP-CR during 5500–4500 BP,while climate deterioration caused humans to retreat to lower altitudes.During 3600–2200 BP,a range of livelihoods emerged in different regions of the NETPCR.This was promoted by early trans-Eurasian exchange and the development of an agro-pastoral economy that utilized cold-tolerant crops and livestock.This eventually promoted the expansion of permanent human settlements to high-altitude areas in the NETP.This study found that human societies adopted various strategies to adapt to the changing living environment throughout late prehistoric times in the NETP-CR.The results provide a long-term perspective on the trajectory of regional socio-environmental co-evolution.
文摘The goal of this research is to describe and analyze women’s wear in the late Qing Dynasty andearly Republic Period(late 19th c.—early 20th c.),with an emphasis on the daily informal orsemi-formal wear,though some formal or ceremonial costumes such as wedding dress will also beincluded.This study will use Chinese costumes and textiles from many museums to fill in theblanks left by previous research and to give a more detailed and accurate description.It will alsouse historical documents to find the original names of these items and to illustrate a general conceptof their usage on different occasions.The different categories of women’s wear will be described in the following order:①robes orcoats;②jackets;③waistcoats or vests;④skirts;⑤pants and leggings;⑥shoes and socks;⑦headdresses;and⑧others.Of every category,the textiles,decoration,cut,form,style,colourand motif will be discussed.The way in which these items were combined will also be discussed.The comparison between women’s wear and men’s wear,women’s and children’s informal andformal dress will be given.Here are some tentative conclusions.First,the Manchu and Han style coexisted and mixedwith each other and were worn by both Manchu and Han women.Second,the basic silhouettesand cuts were relatively stable and conventional,while the decorations and details(openings,fasten-ings,pleats,vents,collars and hemlines)were different.The former represented accepted socialstandards while the latter could be a matter of personal taste.Third,women’s wear in that periodwere highly stylized,miscellaneous,elaborate,detailed,multicolored and multi-thematic.
文摘Precessing ball solitons (PBS) in a ferromagnet during the first order phase transition is induced by a magnetic field directed along the axis of anisotropy, while the action of the periodic field perpendicular to the main magnetic field has been analyzed. Under these conditions, the characteristics of arising equilibrium PBS are uniquely determined by the frequency of the periodic field, but the solitons with other frequencies are impossible. For such structure, the entropy increase connected with dissipation is compensated by the decrease of the entropy due to the external periodic field. It is shown that the equilibrium PBS are essentially the “self-organizing systems” that can arise spotaneously in a metastable state of ferromagnet.
基金supported by the National Natural Science Foundation of China(Grant Nos.12074107 and 12304195)the Program of Outstanding Young and Middle-Aged Scientific and Technological Innovation Team of Colleges and Universities in Hubei Province(Grant No.T2020001)+2 种基金the Innovation Group Project of the Natural Science Foundation of Hubei Province of China(Grant No.2022CFA012)the Chutian Scholars Program in Hubei Province,the Postdoctoral Fellowship Program of CPSF(Grant No.GZC20230751)the Postdoctoral Innovation Research Program in Hubei Province(Grant No.351342)。
文摘Floquet engineering has attracted considerable attention as a promising approach for tuning topological phase transitions.We investigate the effects of high-frequency time-periodic driving in a four-dimensional(4D)topological insulator,focusing on topological phase transitions at the off-resonant quasienergy gap.The 4D topological insulator hosts gapless three-dimensional boundary states,characterized by the second Chern number C_(2).We demonstrate that the second Chern number of 4D topological insulators can be modulated by tuning the amplitude of time-periodic driving.This includes transitions from a topological phase with C_(2)=±3 to another topological phase with C_(2)=±1,or to a topological phase with an even second Chern number C_(2)=±2,which is absent in the 4D static system.Finally,the approximation theory in the high-frequency limit further confirms the numerical conclusions.
文摘Objective To investigate the therapeutic efficacy of castration with 125 I brachtherapy in middle and late stage prostate cancer. Methods Sixty-six patients with prostate cancer from 2004 to 2009 were analyzed,40 were at clinical stage C and 26 were at clinical stage D,
基金Supported by State Science and Technology Supporting Program(2012BAD07B02)Special Program for Technological Development of Scientific Research Institute of Science and Technology Department(2013EG134237)"Three Rural and Six Party"Science and Technology Cooperation Projects of Zhejiang Province(SN201206)~~
文摘The study aims to solve the problems of late transplanting rice with differ- ent seedling ages at the lower reaches of Yangtze River. We selected six varieties of different thermal and photo-response characteristics as the test material to study the effect of different seedling ages on growth and yield of rice. The results showed that growing period of thermal-response rice was delayed by long seedling age, but less affected by the impact of photo-response rice; the yield of later thermal-re- sponse varieties with 25 days and 30 days seedling ages was significantly reduced. In contrast, the yield of early thermal-response varieties and later photo-response varieties were significantly reduced with 30 days seedling age. The optimal trans- planting seedling age was 15 days of thermal-response rice, while photo-response rice was 20 days. The thermal-response rice should be selected as early maturing varieties, while the photo-response rice could be selected as late maturing varieties for high yield.