MIBS算法是由Izadi等人在CANS 2009上提出的一个轻量级分组密码算法,整体采用Feistel结构,轮函数使用SP结构,分组长度为64 b,包含MIBS-64和MIBS-80这2个版本,适用于资源受限的环境,例如RFID(radio frequency identification)标签.研究M...MIBS算法是由Izadi等人在CANS 2009上提出的一个轻量级分组密码算法,整体采用Feistel结构,轮函数使用SP结构,分组长度为64 b,包含MIBS-64和MIBS-80这2个版本,适用于资源受限的环境,例如RFID(radio frequency identification)标签.研究MIBS算法针对积分攻击的安全性.首先,针对该算法的密钥编排算法,利用密钥搭桥技术,分别得到了MIBS-64和MIBS-80的轮密钥的相关性质.其次,利用基于MILP(mixed integer linear programming)的比特可分性的自动化建模搜索方法,构造了MIBS的8轮和9轮积分区分器.然后,基于8轮积分区分器,给出了12轮MIBS-64的密钥恢复攻击,数据复杂度为2^(60),时间复杂度为2^(63.42);最后,基于9轮积分区分器,给出了14轮MIBS-64的密钥恢复攻击,数据复杂度为2^(63),时间复杂度为2^(66).这是目前对MIBS-64和MIBS-80轮数最长的积分攻击.展开更多
Sluggish kinetics of Mg^2+intercalation and low working potential seriously hinder the development of highenergy-density magnesium-ion batteries(MIBs).Hence developing cathode materials with fast Mg^2+diffusion and hi...Sluggish kinetics of Mg^2+intercalation and low working potential seriously hinder the development of highenergy-density magnesium-ion batteries(MIBs).Hence developing cathode materials with fast Mg^2+diffusion and high working voltage is a key to overcome the obstacles in MIBs.Herein,a tetragonal NaV2O2(PO4)2 F/reduced graphene oxide(r GO)is proposed as an effective Mg^2+host for the first time.It exhibits the highest average discharge voltage(3.3 V vs.Mg^2+/Mg),fast diffusion kinetics of Mg^2+with the average diffusivity of 2.99×10^-10 cm^2s^-1,and ultralong cycling stability(up to 9500 cycles).The Mg^2+storage mechanism of NaV2O2(PO4)2 F/r GO is demonstrated as a single-phase(de)intercalation reaction by in situ X-ray diffraction(XRD)technology.Density functional theory(DFT)computations further reveal that Mg^2+ions tend to migrate along the a direction.X-ray absorption near edge structure(XANES)demonstrates a decrease in the average valence of vanadium,and the local coordination environment around vanadium site is highly conserved after magnesiation.Moreover,the assembled NaV2O2(PO4)2 F//Mg0.79NaTi2(PO4)3 Mg-ion full cell exhibits high power and energy densities,which indicates that NaV2O2(PO4)2 F/r GO owns potential for practical applications.This work achieves a breakthrough in the working voltage of cathode materials for MIBs and provides a new opportunity for high-energy-density MIBs.展开更多
Aim: The aim of the present study was to examine associations among maternal stress level, general health, mother to infant bonding, maternal depression level, and mode of delivery. Methods: Mothers who delivered a si...Aim: The aim of the present study was to examine associations among maternal stress level, general health, mother to infant bonding, maternal depression level, and mode of delivery. Methods: Mothers who delivered a single baby at term were recruited with a total 435 mothers participating in the study. Outcome measures: Data were collected 6 months after delivery using General Health Questionnaire (GHQ-28), Mother-to-Infant Bonding Scale (MIBS), Edinburgh Postnatal Depression Scale (EPDS) as well as socio-demographic and medical information at 6 months. Additionally, salivary cortisol and chromogranin levels were determined. Results: The proportion of breast-feeding mothers in the vaginal delivery group (51.4%) was significantly higher than that of the cesarean section group (24%). GHQ-28 scores were significantly related to EPDS scores and MIBS scores (P Conclusion: Maternal general health is associated with maternal psychological health. These results suggest that the support of maternal health is important to maintain maternal psychological status and bonding to infants. Because EPDS scores were significantly worse in the planned cesarean section group (4.2 ± 3.3), careful management is needed of mothers who deliver by planned cesarean section.展开更多
文摘MIBS算法是由Izadi等人在CANS 2009上提出的一个轻量级分组密码算法,整体采用Feistel结构,轮函数使用SP结构,分组长度为64 b,包含MIBS-64和MIBS-80这2个版本,适用于资源受限的环境,例如RFID(radio frequency identification)标签.研究MIBS算法针对积分攻击的安全性.首先,针对该算法的密钥编排算法,利用密钥搭桥技术,分别得到了MIBS-64和MIBS-80的轮密钥的相关性质.其次,利用基于MILP(mixed integer linear programming)的比特可分性的自动化建模搜索方法,构造了MIBS的8轮和9轮积分区分器.然后,基于8轮积分区分器,给出了12轮MIBS-64的密钥恢复攻击,数据复杂度为2^(60),时间复杂度为2^(63.42);最后,基于9轮积分区分器,给出了14轮MIBS-64的密钥恢复攻击,数据复杂度为2^(63),时间复杂度为2^(66).这是目前对MIBS-64和MIBS-80轮数最长的积分攻击.
基金supported by the National Key Research and Development Program of China(2016YFA0202603 and 2016YFA0202601)the National Natural Science Fund for Distinguished Young Scholars(51425204)+1 种基金the National Natural Science Foundation of China(51832004,51602239 and 51672307)the International Science&Technology Cooperation Program of China(2013DFA50840)。
文摘Sluggish kinetics of Mg^2+intercalation and low working potential seriously hinder the development of highenergy-density magnesium-ion batteries(MIBs).Hence developing cathode materials with fast Mg^2+diffusion and high working voltage is a key to overcome the obstacles in MIBs.Herein,a tetragonal NaV2O2(PO4)2 F/reduced graphene oxide(r GO)is proposed as an effective Mg^2+host for the first time.It exhibits the highest average discharge voltage(3.3 V vs.Mg^2+/Mg),fast diffusion kinetics of Mg^2+with the average diffusivity of 2.99×10^-10 cm^2s^-1,and ultralong cycling stability(up to 9500 cycles).The Mg^2+storage mechanism of NaV2O2(PO4)2 F/r GO is demonstrated as a single-phase(de)intercalation reaction by in situ X-ray diffraction(XRD)technology.Density functional theory(DFT)computations further reveal that Mg^2+ions tend to migrate along the a direction.X-ray absorption near edge structure(XANES)demonstrates a decrease in the average valence of vanadium,and the local coordination environment around vanadium site is highly conserved after magnesiation.Moreover,the assembled NaV2O2(PO4)2 F//Mg0.79NaTi2(PO4)3 Mg-ion full cell exhibits high power and energy densities,which indicates that NaV2O2(PO4)2 F/r GO owns potential for practical applications.This work achieves a breakthrough in the working voltage of cathode materials for MIBs and provides a new opportunity for high-energy-density MIBs.
文摘Aim: The aim of the present study was to examine associations among maternal stress level, general health, mother to infant bonding, maternal depression level, and mode of delivery. Methods: Mothers who delivered a single baby at term were recruited with a total 435 mothers participating in the study. Outcome measures: Data were collected 6 months after delivery using General Health Questionnaire (GHQ-28), Mother-to-Infant Bonding Scale (MIBS), Edinburgh Postnatal Depression Scale (EPDS) as well as socio-demographic and medical information at 6 months. Additionally, salivary cortisol and chromogranin levels were determined. Results: The proportion of breast-feeding mothers in the vaginal delivery group (51.4%) was significantly higher than that of the cesarean section group (24%). GHQ-28 scores were significantly related to EPDS scores and MIBS scores (P Conclusion: Maternal general health is associated with maternal psychological health. These results suggest that the support of maternal health is important to maintain maternal psychological status and bonding to infants. Because EPDS scores were significantly worse in the planned cesarean section group (4.2 ± 3.3), careful management is needed of mothers who deliver by planned cesarean section.