Based on the charge storage mode,it is important to investigate the scaling dependence of memory performance in silicon nanocrystal(Si-NC) nonvolatile memory(NVM) devices for its scaling down limit.In this work,we...Based on the charge storage mode,it is important to investigate the scaling dependence of memory performance in silicon nanocrystal(Si-NC) nonvolatile memory(NVM) devices for its scaling down limit.In this work,we made eight kinds of test key cells with different gate widths and lengths by 0.13-μm node complementary metal oxide semiconductor(CMOS) technology.It is found that the memory windows of eight kinds of test key cells are almost the same of about1.64 V @ ±7 V/1 ms,which are independent of the gate area,but mainly determined by the average size(12 nm) and areal density(1.8×10^(11)/cm^2) of Si-NCs.The program/erase(P/E) speed characteristics are almost independent of gate widths and lengths.However,the erase speed is faster than the program speed of test key cells,which is due to the different charging behaviors between electrons and holes during the operation processes.Furthermore,the data retention characteristic is also independent of the gate area.Our findings are useful for further scaling down of Si-NC NVM devices to improve the performance and on-chip integration.展开更多
Pulsed microwaves are widely used inradar,navigation, and communication. The average power density is low at narrow pulse widths or large pulse intervals,but pulsed microwaves at certain peak densities exert numerous ...Pulsed microwaves are widely used inradar,navigation, and communication. The average power density is low at narrow pulse widths or large pulse intervals,but pulsed microwaves at certain peak densities exert numerous biological effects, including展开更多
One of the most intriguing questions in eusocial insects is to understand how the overt reproductive conflict in the colony appears limited when queens or kings are senescent or lost because the morphologically simila...One of the most intriguing questions in eusocial insects is to understand how the overt reproductive conflict in the colony appears limited when queens or kings are senescent or lost because the morphologically similar individuals in the colony are reproductively totipotent.Whether there are some individuals who preferentially differentiate into replacement reproductives or not has received little attention.The consistent individual behavioral differences(also termed“animal personality”)of individuals from the colony can shape cunningly their task and consequently affect the colony fitness but have been rarely investigated in eusocial insects.Here,we used the termite Reticulitermes labralis to investigate if variations in individual personalities(elusiveness and aggressiveness)may predict which individuals will perform reproductive differentiation within colonies.We observed that when we separately reared elusive and aggressive workers,elusive workers differentiate into reproductives significantly earlier than aggressive workers.When we reared them together in the proportions 12:3,10:5,and 8:7(aggressive workers:elusive workers),the first reproductives mostly differentiated from the elusive workers,and the reproductives differentiated from the elusive workers significantly earlier than from aggressive workers.Furthermore,we found that the number of workers participating in reproductive differentiation was significantly lower in the groups of both types of workers than in groups containing only elusive workers.Our results demonstrate that the elusiveness trait was a strong predictor of workers’differentiation into replacement reproductives in R.labralis.Moreover,our results suggest that individual personalities within the insect society could play a key role in resolving the overt reproductive conflict.展开更多
Background:China has achieved universal health insurance coverage.This study examined how patients and hospitals react to the different designs of the plans and to monitoring of patients by the local authority in the...Background:China has achieved universal health insurance coverage.This study examined how patients and hospitals react to the different designs of the plans and to monitoring of patients by the local authority in the Chinese multiple health security schemes.Methods:The sample for analysis consisted of 1006 orthopedic inpatients who were admitted between January and December 2011 at a tertiary teaching hospital located in Beijing.We conducted general linear regression analyses to investigate whether medical expenditure and length of stay differed according to the different incentives.Results:Patients under plans with lower copayment rates consumed significantly more medication compared with those under plans with higher copayment rates.Under plans with an annual ceiling for insurance coverage,patients spent significantly more in the second half of the year than in the first half of the year.The length of stay was shorter among patients when there were government monitoring and a penalty to the hospital service provider.Conclusions:Our results indicate that the different designs and monitoring of the health security systems in China cause opportunistic behavior by patients and providers.Reformation is necessary to reduce those incentives,and improve equity and efficiency in healthcare use.展开更多
基金Project supported by the State Key Development Program for Basic Research of China(Grant No.2010CB934402)the National Natural Science Foundation of China(Grant Nos.11374153,61571221,and 61071008)
文摘Based on the charge storage mode,it is important to investigate the scaling dependence of memory performance in silicon nanocrystal(Si-NC) nonvolatile memory(NVM) devices for its scaling down limit.In this work,we made eight kinds of test key cells with different gate widths and lengths by 0.13-μm node complementary metal oxide semiconductor(CMOS) technology.It is found that the memory windows of eight kinds of test key cells are almost the same of about1.64 V @ ±7 V/1 ms,which are independent of the gate area,but mainly determined by the average size(12 nm) and areal density(1.8×10^(11)/cm^2) of Si-NCs.The program/erase(P/E) speed characteristics are almost independent of gate widths and lengths.However,the erase speed is faster than the program speed of test key cells,which is due to the different charging behaviors between electrons and holes during the operation processes.Furthermore,the data retention characteristic is also independent of the gate area.Our findings are useful for further scaling down of Si-NC NVM devices to improve the performance and on-chip integration.
基金supported by the Foundation of Astronaut Research and Training Center of China [No.SMFA14B06 and No.14ZS017]
文摘Pulsed microwaves are widely used inradar,navigation, and communication. The average power density is low at narrow pulse widths or large pulse intervals,but pulsed microwaves at certain peak densities exert numerous biological effects, including
基金This work was supported by the NSFC-Yunnan United fund(U2102221)National Natural Science Foundation of China(31360104)by the Project for Graduate Innovation Team of Northwestern Polytechnical University(02020-19GH010208),Xi'an,China。
文摘One of the most intriguing questions in eusocial insects is to understand how the overt reproductive conflict in the colony appears limited when queens or kings are senescent or lost because the morphologically similar individuals in the colony are reproductively totipotent.Whether there are some individuals who preferentially differentiate into replacement reproductives or not has received little attention.The consistent individual behavioral differences(also termed“animal personality”)of individuals from the colony can shape cunningly their task and consequently affect the colony fitness but have been rarely investigated in eusocial insects.Here,we used the termite Reticulitermes labralis to investigate if variations in individual personalities(elusiveness and aggressiveness)may predict which individuals will perform reproductive differentiation within colonies.We observed that when we separately reared elusive and aggressive workers,elusive workers differentiate into reproductives significantly earlier than aggressive workers.When we reared them together in the proportions 12:3,10:5,and 8:7(aggressive workers:elusive workers),the first reproductives mostly differentiated from the elusive workers,and the reproductives differentiated from the elusive workers significantly earlier than from aggressive workers.Furthermore,we found that the number of workers participating in reproductive differentiation was significantly lower in the groups of both types of workers than in groups containing only elusive workers.Our results demonstrate that the elusiveness trait was a strong predictor of workers’differentiation into replacement reproductives in R.labralis.Moreover,our results suggest that individual personalities within the insect society could play a key role in resolving the overt reproductive conflict.
文摘Background:China has achieved universal health insurance coverage.This study examined how patients and hospitals react to the different designs of the plans and to monitoring of patients by the local authority in the Chinese multiple health security schemes.Methods:The sample for analysis consisted of 1006 orthopedic inpatients who were admitted between January and December 2011 at a tertiary teaching hospital located in Beijing.We conducted general linear regression analyses to investigate whether medical expenditure and length of stay differed according to the different incentives.Results:Patients under plans with lower copayment rates consumed significantly more medication compared with those under plans with higher copayment rates.Under plans with an annual ceiling for insurance coverage,patients spent significantly more in the second half of the year than in the first half of the year.The length of stay was shorter among patients when there were government monitoring and a penalty to the hospital service provider.Conclusions:Our results indicate that the different designs and monitoring of the health security systems in China cause opportunistic behavior by patients and providers.Reformation is necessary to reduce those incentives,and improve equity and efficiency in healthcare use.