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Transition Periods Between Sea Ice Concentration and Sea Surface Air Temperature in the Arctic Revealed by an Abnormal Running Correlation 被引量:2
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作者 JI Xupeng ZHAO Jinping 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第3期633-642,共10页
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
关键词 ARCTIC SEA ice CONCENTRATION SEA surface air temperature synthetic running CORRELATION coefficient transition period
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Repeated inoculation with rumen fluid accelerates the rumen bacterial transition with no benefit on production performance in postpartum Holstein dairy cows
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作者 Fanlin Kong Feiran Wang +3 位作者 Yijia Zhang Shuo Wang Wei Wang Shengli Li 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期795-811,共17页
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
关键词 Dairy cow LIPIDOMICS Liver Rumen microbiota transplantation transition period
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Lost Women in Social Transitional Period——A Comparative Study of the Tragic Fate of Sister Carrie and Guo Haizao
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作者 陈晶晶 《海外英语》 2014年第14期172-173,176,共3页
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
关键词 SISTER CARRIE DWELLING SOCIAL transitional period
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Empirical Research on the Factors of Chinese City Growth in the Transitional Period
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作者 LI Yingjie YANG Yongchun 《Asian Agricultural Research》 2010年第7期1-5,共5页
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
关键词 transitional period City growth Chinese cities FACTORS China
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Topological phase transition in cavity optomechanical system with periodical modulation
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作者 Zhi-Xu Zhang Lu Qi +2 位作者 Wen-Xue Cui Shou Zhang Hong-Fu Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第7期104-111,共8页
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
关键词 topological phase transition periodical modulation enhanced topological effect
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Floquet dynamical quantum phase transitions in transverse XY spin chains under periodic kickings
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作者 栾丽娜 张镁玉 王林成 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期144-152,共9页
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
关键词 Floquet dynamical quantum phase transitions periodic kick XY spin chains
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Chinese Thoughts on domain on the value of standard during the period of social transition
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作者 Ping-JingQiu 《International Journal of Technology Management》 2014年第5期19-21,共3页
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
关键词 transition period VALUE DOMAIN
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A model of local labor market regulation of China in the transition period
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作者 VeQi 《Ecological Economy》 2009年第1期50-61,共12页
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
关键词 Local labor market REGULATION transition period
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Optimized segmented regression models for the transition period of intervention effects
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作者 Xiangliang Zhang Kunpeng Wu +5 位作者 Yan Pan Rong Yin Yi Zhang Di Kong Qi Wang Wen Chen 《Global Health Research and Policy》 2023年第1期240-252,共13页
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
关键词 Segmented regression transition period Intervention evaluation Cumulative distribution functions Distribution patterns
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Effects of far-off and close-up transition cow feeding on uterine health,postpartum anestrous interval,and reproductive outcomes in pasture-based dairy cows 被引量:3
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作者 S.Meier J.K.Kay +6 位作者 B.Kuhn-Sherlock A.Heiser M.D.Mitchell M.A.Crookenden M.Vailati Riboni J.J.Loor J.R.Roche 《Journal of Animal Science and Biotechnology》 CAS CSCD 2020年第2期493-503,共11页
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
关键词 Close-up Dairy cows Far-off Reproduction transition period
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Precessing Ball Solitons as Self-Organizing Systems during a Phase Transition in a Ferromagnet
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作者 V. V. Nietz 《Applied Mathematics》 2013年第10期78-83,共6页
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
关键词 FERROMAGNET MAGNETIC FIELD periodic MAGNETIC FIELD First-Order Phase transition Precessing BALL Soliton DISSIPATIVE MAGNETIC Structures SELF-ORGANIZING Systems
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Tuning Second Chern Number in a Four-Dimensional Topological Insulator by High-Frequency Time-Periodic Driving
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作者 刘峥嵘 陈锐 周斌 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第4期77-89,共13页
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
关键词 TOPOLOGICAL transitionS periodIC
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Multifaceted role of one-carbon metabolism on immunometabolic control and growth during pregnancy, lactation and the neonatal period in dairy cattle 被引量:6
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作者 Danielle N.Coleman Abdulrahman S.Alharthi +4 位作者 Yusheng Liang Matheus Gomes Lopes Vincenzo Lopreiato Mario Vailati-Riboni Juan J.Loor 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第1期82-109,共28页
Dairy cattle undergo dramatic metabolic, endocrine, physiologic and immune changes during the peripartal period largely due to combined increases in energy requirements for fetal growth and development, milk productio... Dairy cattle undergo dramatic metabolic, endocrine, physiologic and immune changes during the peripartal period largely due to combined increases in energy requirements for fetal growth and development, milk production, and decreased dry matter intake. The negative nutrient balance that develops results in body fat mobilization,subsequently leading to triacylglycerol(TAG) accumulation in the liver along with reductions in liver function,immune dysfunction and a state of inflammation and oxidative stress. Mobilization of muscle and gluconeogenesis are also enhanced, while intake of vitamins and minerals is decreased, contributing to metabolic and immune dysfunction and oxidative stress. Enhancing post-ruminal supply of methyl donors is one approach that may improve immunometabolism and production synergistically in peripartal cows. At the cellular level, methyl donors(e.g. methionine, choline, betaine and folic acid) interact through one-carbon metabolism to modulate metabolism,immune responses and epigenetic events. By modulating those pathways, methyl donors may help increase the export of very low-density lipoproteins to reduce liver TAG and contribute to antioxidant synthesis to alleviate oxidative stress. Thus, altering one-carbon metabolism through methyl donor supplementation is a viable option to modulate immunometabolism during the peripartal period. This review explores available data on the regulation of one-carbon metabolism pathways in dairy cows in the context of enzyme regulation, cellular sensors and signaling mechanisms that might respond to increased dietary supply of specific methyl donors. Effects of methyl donors beyond the one-carbon metabolism pathways, including production performance, immune cell function,mechanistic target or rapamycin signaling, and fatty acid oxidation will also be highlighted. Furthermore, the effects of body condition and feeding system(total mixed ration vs. pasture) on one-carbon metabolism pathways are explored. Potential effects of methyl donor supply during the pepartum period on dairy calf growth and development also are discussed. Lastly, practical nutritional recommendations related to methyl donor metabolism during the peripartal period are presented. Nutritional management during the peripartal period is a fertile area of research, hence, underscoring the importance for developing a systems understanding of the potential immunometabolic role that dietary methyl donors play during this period to promote health and performance. 展开更多
关键词 EPIGENETICS Immune system METABOLISM Methyl donor transition period
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Supplemental Smartamine M in higher-energy diets during the prepartal period improves hepatic biomarkers of health and oxidative status in Holstein cows 被引量:3
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作者 Mario Vailati-Riboni Johan S.Osorio +2 位作者 Erminio Trevisi Daniel Luchini Juan J.Loor 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第3期624-635,共12页
Background: Feeding higher-energy prepartum is a common practice in the dairy industry. However, recent data underscore how it could reduce performance, deepen negative energy balance, and augment inflammation and ox... Background: Feeding higher-energy prepartum is a common practice in the dairy industry. However, recent data underscore how it could reduce performance, deepen negative energy balance, and augment inflammation and oxidative stress in fresh cows. We tested the effectiveness of rumen-protected methionine in preventing the negative effect of feeding a higher-energy prepartum. Multiparous Holstein cows were fed a control lower-energy diet(CON, 1.24 Mcal/kg DM; high-straw) during the whole dry period(-50 d), or were switched to a higher-energy(OVE, 1.54 Mcal/kg DM), or OVE plus Smartamine M(OVE + SM; Adisseo NA) during the last 21 d before calving.Afterwards cows received the same lactation diet(1.75 Mcal/kg DM). Smartamine M was top-dressed on the OVE diet(0.07% of DM) from -21 through 30 d in milk(DIM). Liver samples were obtained via percutaneous biopsy at -10, 7 and 21 DIM. Expression of genes associated with energy and lipid metabolism, hepatokines, methionine cycle, antioxidant capacity and inflammation was measured.Results: Postpartal dry matter intake, milk yield, and energy-corrected milk were higher in CON and OVE + SM compared with OVE. Furthermore, milk protein and fat percentages were greater in OVE + SM compared with CON and OVE. Expression of the gluconeogenic gene PCK1 and the lipid-metabolism transcription regulator PPARA was again greater with CON and OVE + SM compared with OVE. Expression of the lipoprotein synthesis enzyme MTTP was lower in OVE + SM than CON or OVE. Similarly, the hepatokine FGF21, which correlates with severity of negative energy balance, was increased postpartum only in OVE compared to the other two groups. These results indicate greater liver metabolism and functions to support a greater production in OVE + SM. At 7 DIM, the enzyme GSR involved in the synthesis of glutathione tended to be upregulated in OVE than CON-fed cows, suggesting a greater antioxidant demand in overfed cows. Feeding OVE + SM resulted in lower similar expression of GSR compared with CON. Expression of the methionine cycle enzymes SAHH and MTR, both of which help synthesize methionine endogenously, was greater prepartum in OVE + SM compared with both CON and OVE, and at 7 DIM for CON and OVE + SM compared with OVE, suggesting greater Met availability. It is noteworthy that DNMT3A, which utilizes S-adenosylmethionine generated in the methionine cycle, was greater in OVE and OVE + SM indicating higher-energy diets might enhance DNA methylation, thus, Met utilization.Conclusions: Data indicate that supplemental Smartamine M was able to compensate for the negative effect of prepartal energy-overfeeding by alleviating the demand for intracellular antioxidants, thus, contributing to the increase in production. Moreover Smartamine M improved hepatic lipid and glucose metabolism, leading to greater liver function and better overall health. 展开更多
关键词 Energy Methionine Nutrigenomics transition period
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Stability of Nonlinear Feedback Shift Registers with Periodic Input 被引量:2
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作者 Bo Gao Xuan Liu +5 位作者 Xiaobo Wu Shudong Li Zhongzhou Lan Hui Lu Boyan Liu 《Computers, Materials & Continua》 SCIE EI 2020年第2期833-847,共15页
The stability of Non-Linear Feedback Shift Registers(NFSRs)plays an important role in the cryptographic security.Due to the complexity of nonlinear systems and the lack of efficient algebraic tools,the theorems relate... The stability of Non-Linear Feedback Shift Registers(NFSRs)plays an important role in the cryptographic security.Due to the complexity of nonlinear systems and the lack of efficient algebraic tools,the theorems related to the stability of NFSRs are still not well-developed.In this paper,we view the NFSR with periodic inputs as a Boolean control network.Based on the mathematical tool of semi-tensor product(STP),the Boolean network can be mapped into an algebraic form.Through these basic theories,we analyze the state space of non-autonomous NFSRs,and discuss the stability of an NFSR with periodic inputs of limited length or unlimited length.The simulation results are provided to prove the efficiency of the model.Based on these works,we can provide a method to analyze the stability of the NFSR with periodic input,including limited length and unlimited length.By this,we can efficiently reduce the computational complexity,and its efficiency is demonstrated by applying the theorem in simulations dealing with the stability of a non-autonomous NFSR. 展开更多
关键词 Non-Linear Feedback Shift Register(NFSR) Boolean Network(BN) Semi-Tensor Product(STP) transition matrix STABILITY periodic input
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Sedimentology and sequence stratigraphy of the mixed clastic-carbonate deposits in the Late Paleozoic icehouse period:A case study from the northern Qaidam Basin 被引量:2
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作者 Xiao-jie Wei Zong-xing Li +4 位作者 Yin-sheng Ma Yi-fan Li Jun-jie Hu Kui Liu Xin-xin Fang 《China Geology》 2021年第4期673-685,共13页
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
关键词 Late Paleozoic icehouse period Mixed clastic-carbonate succession Marine-continental transition Sedimentation-climate response Geological survey engineering Qinghai-Tibetan Plateau
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Last train timetable optimization for metro network to maximize the passenger accessibility over the end-of-service period 被引量:1
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作者 Fang Wen Yun Bai +2 位作者 Xin Zhang Yao Chen Ninghai Li 《Railway Sciences》 2023年第2期273-288,共16页
Purpose-This study aims to improve the passenger accessibility of passenger demands in the end-ofoperation period.Design/methodology/approach-A mixed integer nonlinear programming model for last train timetable optim... Purpose-This study aims to improve the passenger accessibility of passenger demands in the end-ofoperation period.Design/methodology/approach-A mixed integer nonlinear programming model for last train timetable optimization of the metro was proposed considering the constraints such as the maximum headway,the minimum headway and the latest end-of-operation time.The objective of the model is to maximize the number of reachable passengers in the end-of-operation period.A solution method based on a preset train service is proposed,which significantly reduces the variables of deciding train services in the original model and reformulates it into a mixed integer linear programming model.Findings-The results of the case study of Wuhan Metro show that the solution method can obtain highquality solutions in a shorter time;and the shorter the time interval of passenger flow data,the more obvious the advantage of solution speed;after optimization,the number of passengers reaching the destination among the passengers who need to take the last train during the end-of-operation period can be increased by 10%.Originality/value-Existing research results only consider the passengers who take the last train.Compared with previous research,considering the overall passenger demand during the end-of-operation period can make more passengers arrive at their destination.Appropriately delaying the end-of-operation time can increase the proportion of passengers who can reach the destination in the metro network,but due to the decrease in passenger demand,postponing the end-of-operation time has a bottleneck in increasing the proportion of passengers who can reach the destination. 展开更多
关键词 Urban rail transit Last train of metro Timetable optimization End-of-operation period Passenger demand OD reachability
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THE EXISTENCE OF PERIODIC SOLUTIONS TO DISCRETE—TIME NONLINEAR STOCHASTIC SYSTEMS
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作者 胡良剑 《Journal of China Textile University(English Edition)》 EI CAS 1996年第1期80-88,共9页
In this paper, we have presented some general necessary and sufficient conditions for the existence of periodic solutions to nonlinear stochastic difference equations on semi-compact topological space. Effective suffi... In this paper, we have presented some general necessary and sufficient conditions for the existence of periodic solutions to nonlinear stochastic difference equations on semi-compact topological space. Effective sufficient conditions in terms of Lyapunov functions are derived for the systems linear in noise. 展开更多
关键词 semi-compact periodIC STOCHASTIC process STOCHASTIC DIFFERENCE equation TIGHTNESS transition PROBABILITY
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THE PERIODICITY OF FLARE OCCURRENCE IN EVOLUTION OF AR5395 (ABSTRACT)
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作者 Lin Huaan Wang ShijinCenter For Space Science and applied research Chinese Academy of Sciences, Beijing 《天文研究与技术》 CSCD 1990年第4期81-81,共1页
Since the beganning of the routine measurement of solar X-ray flares in 1974, activeregion 5395 was the most prolific X-ray flare producer. During the disk transit ofAR5395 about 12-13 days, a total of 11 class X and ... Since the beganning of the routine measurement of solar X-ray flares in 1974, activeregion 5395 was the most prolific X-ray flare producer. During the disk transit ofAR5395 about 12-13 days, a total of 11 class X and 48 class M flares was observed.Taken an average, about one class X flare per day was produced. The data of 展开更多
关键词 PRODUCER routine RELEASED transit integer periodICAL
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新入职护士过渡期不同阶段职场适应的真实体验 被引量:1
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作者 韩娟 张蜜 +5 位作者 高雅 李洁琼 马佳佳 汤逸蘋 游宁 刘婷 《护士进修杂志》 2024年第20期2145-2150,共6页
目的探索新入职护士在过渡期不同阶段职场适应的工作体验,了解其在护理岗位适应过程中面临的各种压力、情感体验及行为形成,进一步探索并优化新入职护士培训方案的相关内容。方法本研究采用现象学研究方法,于2023年3-6月在西安交通大学... 目的探索新入职护士在过渡期不同阶段职场适应的工作体验,了解其在护理岗位适应过程中面临的各种压力、情感体验及行为形成,进一步探索并优化新入职护士培训方案的相关内容。方法本研究采用现象学研究方法,于2023年3-6月在西安交通大学第一附属医院对20名新入职护士进行半结构式深入访谈,并使用Colaizzi 7步分析法对访谈内容进行整理分析。结果提炼得出4个主题和9个亚主题,分别为职业认知(入职1个月)(工作环境不熟悉、角色转化困难、职业认同困扰)、学习适应(2~3个月)(岗位能力不足、自我否定、)、融入环境(4~6个月)(缺乏专科知识、缺乏组织归属感、)、职业胜任(7~12个月)(预警和应对突发事件能力不足、岗位不确定性所致的焦虑)。结论新入职护士过渡期的规范化培训对其职业适应及职业发展至关重要,护理管理者可通过了解新护士过渡期不同阶段职场适应的工作体验,优化培训方案,增加新护士职业认同、心理健康的相关培训,帮助新护士尽早适应临床工作。 展开更多
关键词 新入职护士 过渡期 职场适应 真实体验 质性研究
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