[Objective] The paper was to study the dynamic changes of forage nutrient substance fermentation in rumen, and a set of continuous culture system of artificial rumen was designed. [Method] With in vivo as control, the...[Objective] The paper was to study the dynamic changes of forage nutrient substance fermentation in rumen, and a set of continuous culture system of artificial rumen was designed. [Method] With in vivo as control, the simulating rumen fer- mentation effect in vitro culture system was evaluated. [Result] The simulation rumen fermentation test needed adaptive phase of 2-3 d, and the fermentation state was relatively stable within 3-9 d, with good effects. The test showed certain regularity variation with index value of rumen in vivo. [Conclusion] The continuous culture sys- tem of artificial rumen could be used as the ideal model to study the rumen fermen- tation in vivo.展开更多
A scoping review was conducted to report on the nature and extent of the literature addressing the transition through peri and post retirement for people living with chronic disorder(s). The secondary purpose was to...A scoping review was conducted to report on the nature and extent of the literature addressing the transition through peri and post retirement for people living with chronic disorder(s). The secondary purpose was to determine the extent that gender issues and the transition age (50-65) are specifically addressed. Of 3,256 titles identified, 111 articles meet the inclusion criteria. Information was often indirect but addressed varying health domains that significantly influence transitional stages toward retirement and illustrating the burden of chronic comorbid health problems, unequal gender positions with differences in labour force participation, retirement pensions, and changing social dynamics. Few studies directly addressed the complex interaction of chronic health outcomes, psychological well-being, social and financial health as a significant paradigm in determining a successful transition into retirement. Needed are prospective longitudinal studies that measure predictors and outcomes of retirement transitioning along with qualitative studies that define the decision-making process. Given the substantial differential impact in respect to retirement risk factors and opportunities, there must be consideration in design and analysis for future high quality research.展开更多
A multicellular DCX (dc-dc transformer) using unregulated cell converters has been proposed for the environmentally friendly data centers. The high speed cell converter with the switching frequency over MHz behaves ...A multicellular DCX (dc-dc transformer) using unregulated cell converters has been proposed for the environmentally friendly data centers. The high speed cell converter with the switching frequency over MHz behaves as an ideal transformer, and this behavior solves the voltage imbalance issue in the multicellular converter topology. The analysis of the unregulated cell converter is conducted by using the state space averaging method, and the operation condition for the ideal transformer is specified. The behavior of the multicellular DCX using the high speed cell converters has been also analyzed, and the voltage imbalance issue among cell converters is discussed quantitatively. A prototype of a 19.2 kW 384 V-384 V multicellular DCX using sixty-four unregulated cell converters is fabricated and the validity of the analyses is verified.展开更多
Seldom could metals and alloys maintain excellent properties in cryogenic condition, such as the ductility, owing to the restrained dislocation motion.However, a face-centered-cubic(FCC) CoCrFeNi highentropy alloy(HEA...Seldom could metals and alloys maintain excellent properties in cryogenic condition, such as the ductility, owing to the restrained dislocation motion.However, a face-centered-cubic(FCC) CoCrFeNi highentropy alloy(HEA) with great ductility is investigated under the cryogenic environment. The tensile strength of this alloy can reach a maximum at 1,251±10 MPa, and the strain to failure can stay at as large as 62% at the liquid helium temperature. We ascribe the high strength and ductility to the low stacking fault energy at extremely low temperatures,which facilitates the activation of deformation twinning.Moreover, the FCC→HCP(hexagonal close-packed) transition and serration lead to the sudden decline of ductility below 77 K. The dynamical modeling and analysis of serrations at 4.2 and 20 K verify the unstable state due to the FCC→HCP transition. The deformation twinning together with phase transformation at liquid helium temperature produces an adequate strain-hardening rate that sustains the stable plastic flow at high stresses, resulting in the serration feature.展开更多
The T-tubule (TT) system forms the structural basis for excitation-contraction coupling in heart and muscle cells. The morphogenesis of the TT system is a key step in the maturation of heart cells because it does not ...The T-tubule (TT) system forms the structural basis for excitation-contraction coupling in heart and muscle cells. The morphogenesis of the TT system is a key step in the maturation of heart cells because it does not exist in neonatal cardiomyocytes. In the present study, we quantified the morphological changes in TTs during heart cell maturation and investigated the role of junctophilin-2 (JP2), a protein known to anchor the sarcoplasmic reticulum (SR) to TT, in changes to TT morphological parameters. Analysis of confocal images showed that the transverse elements of TTs increased, while longitudinal elements decreased during the maturation of TTs. Fourier transform analysis showed that the power of ~2 m spatial components increased with cardiomyocytes maturation. These changes were preceded by increased expression of JP2, and were reversed by JP2 knockdown. These findings indicate that JP2 is required for the morphogenesis of TTs during heart development.展开更多
Objective: To analyze the heart rate variability in Chinese PLA navy global visiting task group. Methods:We analyzed the heart rate variability in Holter in 77 men and 4 women for 5-15 days before voyage, and 65-75 ...Objective: To analyze the heart rate variability in Chinese PLA navy global visiting task group. Methods:We analyzed the heart rate variability in Holter in 77 men and 4 women for 5-15 days before voyage, and 65-75 and 115-125 days after voyage, and 29 men and 3 women for 5-15 days after having finished voyage. Results:NN50 and VLF were lower in 77 men and 4 women for 65-75 days after voyage than that was 5-15 days before voyage (P<0.01). SDANN was lower in 77 men and 4 women for 115-125 days after voyage than that was 65-75 days after voyage (P<0.01). SDNN, SDANN, SDNN index, RMSSD, NN50, PNN50,Triangular index, VLF, HLF, VAI and VLI were lower in 77 men and 4 women for 65-75 days after voyage than that was 5-15 days before voyage (P<0.01).Conclusion: These findings suggest that voyage may reduce heart rate variability for a long time.展开更多
文摘[Objective] The paper was to study the dynamic changes of forage nutrient substance fermentation in rumen, and a set of continuous culture system of artificial rumen was designed. [Method] With in vivo as control, the simulating rumen fer- mentation effect in vitro culture system was evaluated. [Result] The simulation rumen fermentation test needed adaptive phase of 2-3 d, and the fermentation state was relatively stable within 3-9 d, with good effects. The test showed certain regularity variation with index value of rumen in vivo. [Conclusion] The continuous culture sys- tem of artificial rumen could be used as the ideal model to study the rumen fermen- tation in vivo.
文摘A scoping review was conducted to report on the nature and extent of the literature addressing the transition through peri and post retirement for people living with chronic disorder(s). The secondary purpose was to determine the extent that gender issues and the transition age (50-65) are specifically addressed. Of 3,256 titles identified, 111 articles meet the inclusion criteria. Information was often indirect but addressed varying health domains that significantly influence transitional stages toward retirement and illustrating the burden of chronic comorbid health problems, unequal gender positions with differences in labour force participation, retirement pensions, and changing social dynamics. Few studies directly addressed the complex interaction of chronic health outcomes, psychological well-being, social and financial health as a significant paradigm in determining a successful transition into retirement. Needed are prospective longitudinal studies that measure predictors and outcomes of retirement transitioning along with qualitative studies that define the decision-making process. Given the substantial differential impact in respect to retirement risk factors and opportunities, there must be consideration in design and analysis for future high quality research.
文摘A multicellular DCX (dc-dc transformer) using unregulated cell converters has been proposed for the environmentally friendly data centers. The high speed cell converter with the switching frequency over MHz behaves as an ideal transformer, and this behavior solves the voltage imbalance issue in the multicellular converter topology. The analysis of the unregulated cell converter is conducted by using the state space averaging method, and the operation condition for the ideal transformer is specified. The behavior of the multicellular DCX using the high speed cell converters has been also analyzed, and the voltage imbalance issue among cell converters is discussed quantitatively. A prototype of a 19.2 kW 384 V-384 V multicellular DCX using sixty-four unregulated cell converters is fabricated and the validity of the analyses is verified.
基金supported in part by the Nationa Natural Science Foundation of China (51471025, 51671020, 51471024 and 11771407)the Department of Energy (DOE), Office of Fossil Energy, National Energy Technology Laboratory (DE-FE-0011194)+1 种基金the support from the US Army Research Office project (W911NF-13-1-0438)the support from the National Science Foundation (DMR-1611180 and 1809640)
文摘Seldom could metals and alloys maintain excellent properties in cryogenic condition, such as the ductility, owing to the restrained dislocation motion.However, a face-centered-cubic(FCC) CoCrFeNi highentropy alloy(HEA) with great ductility is investigated under the cryogenic environment. The tensile strength of this alloy can reach a maximum at 1,251±10 MPa, and the strain to failure can stay at as large as 62% at the liquid helium temperature. We ascribe the high strength and ductility to the low stacking fault energy at extremely low temperatures,which facilitates the activation of deformation twinning.Moreover, the FCC→HCP(hexagonal close-packed) transition and serration lead to the sudden decline of ductility below 77 K. The dynamical modeling and analysis of serrations at 4.2 and 20 K verify the unstable state due to the FCC→HCP transition. The deformation twinning together with phase transformation at liquid helium temperature produces an adequate strain-hardening rate that sustains the stable plastic flow at high stresses, resulting in the serration feature.
基金supported by the National Basic Research Program of China (2011CB809101)the National Natural Science Foundation of China (30730013)
文摘The T-tubule (TT) system forms the structural basis for excitation-contraction coupling in heart and muscle cells. The morphogenesis of the TT system is a key step in the maturation of heart cells because it does not exist in neonatal cardiomyocytes. In the present study, we quantified the morphological changes in TTs during heart cell maturation and investigated the role of junctophilin-2 (JP2), a protein known to anchor the sarcoplasmic reticulum (SR) to TT, in changes to TT morphological parameters. Analysis of confocal images showed that the transverse elements of TTs increased, while longitudinal elements decreased during the maturation of TTs. Fourier transform analysis showed that the power of ~2 m spatial components increased with cardiomyocytes maturation. These changes were preceded by increased expression of JP2, and were reversed by JP2 knockdown. These findings indicate that JP2 is required for the morphogenesis of TTs during heart development.
文摘Objective: To analyze the heart rate variability in Chinese PLA navy global visiting task group. Methods:We analyzed the heart rate variability in Holter in 77 men and 4 women for 5-15 days before voyage, and 65-75 and 115-125 days after voyage, and 29 men and 3 women for 5-15 days after having finished voyage. Results:NN50 and VLF were lower in 77 men and 4 women for 65-75 days after voyage than that was 5-15 days before voyage (P<0.01). SDANN was lower in 77 men and 4 women for 115-125 days after voyage than that was 65-75 days after voyage (P<0.01). SDNN, SDANN, SDNN index, RMSSD, NN50, PNN50,Triangular index, VLF, HLF, VAI and VLI were lower in 77 men and 4 women for 65-75 days after voyage than that was 5-15 days before voyage (P<0.01).Conclusion: These findings suggest that voyage may reduce heart rate variability for a long time.