The magnetoresistive properties of discontinuous ferromagnetic Fe and Co thin films deposited by electron-beam sputtering onto glass substrates at room temperature were investigated. Tunnel magnetoresistance(MR) was o...The magnetoresistive properties of discontinuous ferromagnetic Fe and Co thin films deposited by electron-beam sputtering onto glass substrates at room temperature were investigated. Tunnel magnetoresistance(MR) was observed for all of the as-deposited samples. The maximum MR was observed for Fe thin films with an effective thickness of 17 nm. In the case of the Co thin films, the annealing process led to a change of the type of MR to anisotropic at Co film thicknesses(dCo) of 15 ≤ d_(Co) ≤ 25 nm and to positive isotropic at thicknesses of d_(Co) < 15 nm. By contrast, the MR type of Fe thin films did not change.展开更多
Objective:To determine the frequency of risk factors of congestive cardiac failure in a tertiary care hospital of Peshawar.Methods:This retrospective observational study was conducted in department of Cardiology,Postg...Objective:To determine the frequency of risk factors of congestive cardiac failure in a tertiary care hospital of Peshawar.Methods:This retrospective observational study was conducted in department of Cardiology,Postgraduate Medical Institute,Lady Reading Hospital Peshawar,from March 2005 to September 2007.Relevant information regarding the risk factors of congestive cardiac failure were recorded on questionnaire prepared in accordance with the objectives of the study.Results:1 019 patients with established diagnosis of cardiac failure (based on clinical findings and relevant investigations) were included.Out of total sampling 583 (57.12%) were males and 436(42.78%) were females.The age range of the patients was from 6 years to 82 years with mean age of 48.5 years and mode of age was 45 years.The distribution of causative factors of CCF was:ischemic heart disease(IHD) 36.31%,hypertension 26.30%,dilated cardiomyopathy 10.10%,obstructve and restrictive cardiomyopathies 5.39%,valvular heart diseases(VHD) 9.32%,congenital heart disease like ventricular septal defects(VSD) 4.41%,atrial septal defects(ASD) 0.58%,atrial fibrillation (AF) 2.25%,constrictive pericardidtis 1.07%.Pericardial effusion 0.68%,chronic obstructive pulmonary disease and pulmonary hypertension 1.47%,thyrotoxicosis 0.68%,complete heart block 0.29%and paget disease in 0.09%cases.Conclusion:Ischemic heart disease,hypertension,cardiomypathies,valvular heart disease and congenital heart disease are major contributor to CCF in our patients.展开更多
We report two peculiar cases that were observed in two communities of Anambra State,South East Nigeria.The first case was a woman of 44 with a history of blood transfusion from a donor of questionable HIV status.A pin...We report two peculiar cases that were observed in two communities of Anambra State,South East Nigeria.The first case was a woman of 44 with a history of blood transfusion from a donor of questionable HIV status.A pint of blood was transfused in a private Hospital on the 15th January. 2000.She has had no form of antiviral therapy until 22nd April.2008 when she came to the hospital for routine medical check up.Her HIV result came out confirmed positive while that of her husband came out negative.She has had active sexual life with her husband in the previous eight years as they have had some difficulties in getting their desired extra two children having earlier gotten a boy and a girl.The second case involves a family of six.A couple with four children of ages about 6 months,2 years,3 years and 5 years.The youngest,a female presented with fever and multiple lymphadenopathy.She tested HIV positive and so was her mother and her second sibling.But her father and two other siblings remained negative at post three and six months intervals from their very first test date with us.These reported cases appear to go contrary to earher formed opinion on HIV transmission.We support the opinion on a naturally,occurring substance,APOBEC3G which possibly confers permanent immunity against the HIV virus.We recommend clinical trials of the characterized APOBEC3G as a vaccine for non HIV infected persons of all ages and to people living with HIV/AIDS as a therapeutic drug.展开更多
Infantile cerebral palsy is a nonprogressive central motor disturbance of varied etiology.Thespasmodic type is its main form,accounting for 50—60% of the infants afflicted with the dis-ease.The causal factors includ...Infantile cerebral palsy is a nonprogressive central motor disturbance of varied etiology.Thespasmodic type is its main form,accounting for 50—60% of the infants afflicted with the dis-ease.The causal factors include multifarious conditions arising during parturition and in thepre-and postnatal periods.As yet there is no specific treatment for the disease.We haveused a method of applying prompt pressure to peculiar points in treating it and received sat-isfactory results.展开更多
The effect of formed CH_3NH_3 at the heterojunction on properties of CH_3NH_3PbI_3 material is investigated based on experiment and theoretical calculation. Our calculation results show that the giant dielectric const...The effect of formed CH_3NH_3 at the heterojunction on properties of CH_3NH_3PbI_3 material is investigated based on experiment and theoretical calculation. Our calculation results show that the giant dielectric constant, anomalous hysteresis and long-lasting polarization for CH_3NH_3PbI_3 originate from the formed CH_3NH_3 at the heterojunction. It is found that the induced weak EPS by the reorientation of CH_3NH_3 sub-group along the built-in electric field enables us to effectively increase the ordering of entire lead-halide framework. In addition, the heterojunction has an advantage of channel separation between carrier transport and electron diffusion. These properties of the heterojunction are the main origin of the high efficiency of CH_3NH_3PbI_3 solar cells.展开更多
We propose a simple scheme for the generation of a peculiar tripartite entangled state via thermal cavity. The peculiar tripartite entangled state shares features of the GHZ and 14/ state simultaneously. The photon-nu...We propose a simple scheme for the generation of a peculiar tripartite entangled state via thermal cavity. The peculiar tripartite entangled state shares features of the GHZ and 14/ state simultaneously. The photon-numberdependent parts in the effective Hamiltonian are canceled with the assistance of a strong classical field, thus the scheme is insensitive to both the thermal field and the cavity decay. The only thing one needs to do is to modulate the interaction time only once.展开更多
Early-type galaxies (ETGs) are very important for understanding the formation and evolution of galaxies. Recent observations suggest that ETGs are not simply old stellar spheroids as we previously thought. Widesprea...Early-type galaxies (ETGs) are very important for understanding the formation and evolution of galaxies. Recent observations suggest that ETGs are not simply old stellar spheroids as we previously thought. Widespread recent star formation, cool gas and dust have been detected in a substantial fraction of ETGs. We make use of the radial profiles of 9 - r color and the concentration index from the Sloan Digital Sky Survey database to pick out 31 peculiar ETGs with central blue cores. By analyzing the photometric and spectroscopic data, we suggest that the blue cores are caused by star formation activities rather than the central weak active galactic nucleus. From the results of stellar population synthesis, we find that the stellar population of the blue cores is relatively young, spreading from several Myr to less than one Gyr. In 14 galaxies with H I observations, we find that the average gas fraction of these galaxies is about 0.55. The bluer galaxies show a higher gas fraction, and the total star forma- tion rate (SFR) correlates very well with the H I gas mass. The star formation history of these ETGs is affected by the environment, e.g. in the denser environment the H I gas is less and the total SFR is lower. We also discuss the origin of the central star formation of these early-type galaxies.展开更多
The asymptotic solution to the scattering problem on a set of small particles, supplemented into homogeneous material, is used for modeling the materials with the desired refractive index. The consideration concerns t...The asymptotic solution to the scattering problem on a set of small particles, supplemented into homogeneous material, is used for modeling the materials with the desired refractive index. The consideration concerns the case of acoustic scalar scattering and the solution to initial scattering problem is built using an asymptotic approach. The closed form solution is reduced for the scattering problem. This is significant advantage of approach because there is no need to solve the respective system of boundary integral equations. High accuracy of solving the scattering problem is achieved by choosing the optimal parameters of the domain with small particles. The approach allows obtaining an explicit formula for the refractive index of the resulting inhomogeneous material. The numerical calculations show the possibility to get the specific values of refractive index including its negative values.展开更多
BACKGROUND: Translocation or transplantation of nerve stem has good effect; however, nervous function of donator is completely lost. If some nerve stem is damaged, sensory tracts are intercepted from the near nerve s...BACKGROUND: Translocation or transplantation of nerve stem has good effect; however, nervous function of donator is completely lost. If some nerve stem is damaged, sensory tracts are intercepted from the near nerve stem by nutrient vessels to regard as neural graft for transferring and bridging which may repair injured nerve and decrease neural functional loss of donator. OBJECTIVE: To observe anatomical peculiarities on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect, and to investigate its feasibility. DESIGN:Duplicated and measured design.SETTING : Anatomy Department of Medical College affiliated to Nanhua University.MATERIALS: A total of 14 samples of upper limbs were selected from adult unnamed corpse and volunteers.METHODS: The experiment was completed at the Clinical Application Anatomy Laboratory of Medical College affiliated to Nanhua University from September to November 2005. Samples were perfused with red emulsion through artery to observe length, fibrous bands and blood supply of median nerve and ulnar nerve at wrist. Boundary of median nerve at wrist ranged from superficial site between flexor carpi radialis and palmaris Iongus to branch of common palmar digital nerves. Ulnar nerve at wrist ranged from branch of back of the hand to site of common palmar digital nerves. Proximal boundary of the two nerves was crossed from 1/8 to 2/8 region of forearm. Samples of upper limbs from 1 case were selected to simulate operation on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve. MAIN OUTCOME MEASURES: Anatomical peculiarities on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect. RESULTS: ① The length of wrist median nerves was 7.8 (7.5-8.1) cm. There were 19 to 27 nerve tracts in it and the majority belonged to sensory tracts on the ulnar side, in which non-damaged separated length was about 10.0 cm to 14.0 cm. The third, second and first tracts of cutaneous branches at digital interspace and radialis of thumb arrayed from ulnaris to radialis by turns, and numbers of bands were 6.9, 7.4 and 7.2, respectively. The bands in total were 21.6. Cutaneous branches of palm entered from lateral margin of radialis and were completely separated at wrist. Two-thirds of ulnaris at nerve stem, i.e. the third, second and first tracts of cutaneous branches at digital interspace, were separated, which had little effect on sensation in distribution of median nerve. ② Its nutrient vessels originated from radial arteries about 6.2 (6.1-6.6) cm above radial styloid process were 1.2 (1.1-1.4) mm in outer diameter. The length was 5.7 (5.1-6.1) cm.③ The length of wrist ulnar nerve were 9.4 (8.9-9.7) cm and the number of nervous tract were 14 to 19, in which sensory tracts on the anterior external side were approximately equal to motor and mixed tracts on the posterior internal side in quantity. Sensory tracts were located at radialis of palm and motor tracts were located at ulnaris of back. CONCLUSION :① Character and position of median nerve fibre bundle are clear, and length of non-damage separation of sensory tracts is coincidence with the request of transferring to bridge. ② Summation of the third, second and first tracts of cutaneous branches at digital interspace may be satisfactory to bridge of ulnar nerve at wrist (14-19 bands). ③ This technique has little effect on sensation in distribution of median nerve. Nutrient artery of median nerve locates constantly; journey table is superficial and is easily to find out; caliber of arterial canal is thick; blood supply is plentiful; length of pedicel is suitable for translocation. The sensery tracts of wrist median nerve pedicled with nutrient vessels can be applied as nervous grafts to join injured gap in wrist ulnar nerve.展开更多
1 Introduction The observational data of peculiar velocity field of galaxies are important for testing cosmological scenarios. After the pioneer work of Rubin and Ford in 1976, severnl observational results were given...1 Introduction The observational data of peculiar velocity field of galaxies are important for testing cosmological scenarios. After the pioneer work of Rubin and Ford in 1976, severnl observational results were given by different groups, and many theoretical models were presented. Unfortunately, the theoretical results are inconsistent with observational ones. Recently, Ostriker et al. have presented the new concept (cosmic Mach number) and given calculated results. In this note, we will detail calculations of peculiar velocities and cosmic Mach numbers by using some acceptable assumptions.展开更多
The peculiar velocity of quasars is among the data needing extremely to be sought out inthe observational cosmology. Thos paper proposes a method for determining an upper limitto the peculiar velocity of quasars by me...The peculiar velocity of quasars is among the data needing extremely to be sought out inthe observational cosmology. Thos paper proposes a method for determining an upper limitto the peculiar velocity of quasars by means of a statistical analysis of quasar pairs. A pre-liminary conclusion is that the peculiar velocity in the direction along the line joining thetwo quasars in a pair does not exceed, on average, 1000 km/s.展开更多
To the Editor: With interest we read the article by Yu et al[1] about a retrospective study of 13 pediatric patients with Leigh syndrome from a single center in China collected over a period of 17 years. The authors c...To the Editor: With interest we read the article by Yu et al[1] about a retrospective study of 13 pediatric patients with Leigh syndrome from a single center in China collected over a period of 17 years. The authors concluded that patients with ophthalmoplegia, muscle weakness, ataxia, and respiratory insufficiency should be screened for mutations in genes located on the mtDNA.[1] Patients with suspected Leigh syndrome are recommended to undergo determination of cerebrospinal fluid (CSF) lactate and cerebral imaging.[1] We have the following comment and concerns.展开更多
Gas distribution function plays a crucial role in the description of gas flows at the mesoscopic scale.In the presence of non-equilibrium flow,the distribution function loses its rotational symmetricity,making the mat...Gas distribution function plays a crucial role in the description of gas flows at the mesoscopic scale.In the presence of non-equilibrium flow,the distribution function loses its rotational symmetricity,making the mathematical derivation difficult.From both the Chapman-Enskog expansion and the Hermite polynomial expansion(Grad’s method),we observe that the non-equilibrium effect is closely related to the peculiar velocity space(C).Based on this recognition,we propose a new methodology to construct the non-equilibrium distribution function from the perspective of polynomial expansion in the peculiar velocity space of molecules.The coefficients involved in the non-equilibrium distribution function can be exactly determined by the compatibility conditions and the moment relationships.This new framework allows constructing non-equilibrium distribution functions at any order of truncation,and the ones at the third and the fourth order have been presented in this paper for illustration purposes.Numerical validations demonstrate that the new method is more accurate than the Grad’s method at the same truncation error for describing non-equilibrium effects.Two-dimensional benchmark tests are performed to shed light on the applicability of the new method to practical engineering problems.展开更多
基金funded by the State Program of the Ministry of Education and Science of Ukraine (0116U002623)
文摘The magnetoresistive properties of discontinuous ferromagnetic Fe and Co thin films deposited by electron-beam sputtering onto glass substrates at room temperature were investigated. Tunnel magnetoresistance(MR) was observed for all of the as-deposited samples. The maximum MR was observed for Fe thin films with an effective thickness of 17 nm. In the case of the Co thin films, the annealing process led to a change of the type of MR to anisotropic at Co film thicknesses(dCo) of 15 ≤ d_(Co) ≤ 25 nm and to positive isotropic at thicknesses of d_(Co) < 15 nm. By contrast, the MR type of Fe thin films did not change.
文摘Objective:To determine the frequency of risk factors of congestive cardiac failure in a tertiary care hospital of Peshawar.Methods:This retrospective observational study was conducted in department of Cardiology,Postgraduate Medical Institute,Lady Reading Hospital Peshawar,from March 2005 to September 2007.Relevant information regarding the risk factors of congestive cardiac failure were recorded on questionnaire prepared in accordance with the objectives of the study.Results:1 019 patients with established diagnosis of cardiac failure (based on clinical findings and relevant investigations) were included.Out of total sampling 583 (57.12%) were males and 436(42.78%) were females.The age range of the patients was from 6 years to 82 years with mean age of 48.5 years and mode of age was 45 years.The distribution of causative factors of CCF was:ischemic heart disease(IHD) 36.31%,hypertension 26.30%,dilated cardiomyopathy 10.10%,obstructve and restrictive cardiomyopathies 5.39%,valvular heart diseases(VHD) 9.32%,congenital heart disease like ventricular septal defects(VSD) 4.41%,atrial septal defects(ASD) 0.58%,atrial fibrillation (AF) 2.25%,constrictive pericardidtis 1.07%.Pericardial effusion 0.68%,chronic obstructive pulmonary disease and pulmonary hypertension 1.47%,thyrotoxicosis 0.68%,complete heart block 0.29%and paget disease in 0.09%cases.Conclusion:Ischemic heart disease,hypertension,cardiomypathies,valvular heart disease and congenital heart disease are major contributor to CCF in our patients.
文摘We report two peculiar cases that were observed in two communities of Anambra State,South East Nigeria.The first case was a woman of 44 with a history of blood transfusion from a donor of questionable HIV status.A pint of blood was transfused in a private Hospital on the 15th January. 2000.She has had no form of antiviral therapy until 22nd April.2008 when she came to the hospital for routine medical check up.Her HIV result came out confirmed positive while that of her husband came out negative.She has had active sexual life with her husband in the previous eight years as they have had some difficulties in getting their desired extra two children having earlier gotten a boy and a girl.The second case involves a family of six.A couple with four children of ages about 6 months,2 years,3 years and 5 years.The youngest,a female presented with fever and multiple lymphadenopathy.She tested HIV positive and so was her mother and her second sibling.But her father and two other siblings remained negative at post three and six months intervals from their very first test date with us.These reported cases appear to go contrary to earher formed opinion on HIV transmission.We support the opinion on a naturally,occurring substance,APOBEC3G which possibly confers permanent immunity against the HIV virus.We recommend clinical trials of the characterized APOBEC3G as a vaccine for non HIV infected persons of all ages and to people living with HIV/AIDS as a therapeutic drug.
文摘Infantile cerebral palsy is a nonprogressive central motor disturbance of varied etiology.Thespasmodic type is its main form,accounting for 50—60% of the infants afflicted with the dis-ease.The causal factors include multifarious conditions arising during parturition and in thepre-and postnatal periods.As yet there is no specific treatment for the disease.We haveused a method of applying prompt pressure to peculiar points in treating it and received sat-isfactory results.
基金Supported by the National Natural Science Foundation of China under Grant No 61875235the Ph.D. Programs Foundation of Ministry of Education of China under Grant No 20130009110008the Beijing Municipal Education Commission Project under Grant No KM201210015008
文摘The effect of formed CH_3NH_3 at the heterojunction on properties of CH_3NH_3PbI_3 material is investigated based on experiment and theoretical calculation. Our calculation results show that the giant dielectric constant, anomalous hysteresis and long-lasting polarization for CH_3NH_3PbI_3 originate from the formed CH_3NH_3 at the heterojunction. It is found that the induced weak EPS by the reorientation of CH_3NH_3 sub-group along the built-in electric field enables us to effectively increase the ordering of entire lead-halide framework. In addition, the heterojunction has an advantage of channel separation between carrier transport and electron diffusion. These properties of the heterojunction are the main origin of the high efficiency of CH_3NH_3PbI_3 solar cells.
基金The project supported by National Natural Science Foundation of China under Grant No.60678022the Doctoral Fund of the Ministry of Education of China under Grant No.20060357008+1 种基金the Key Program of the Education Department of Anhui Province under Grant Nos.2006KJ070A,KJ2007B082the Youth Foundation of West Anhui University under Grant No.WXCQ0601
文摘We propose a simple scheme for the generation of a peculiar tripartite entangled state via thermal cavity. The peculiar tripartite entangled state shares features of the GHZ and 14/ state simultaneously. The photon-numberdependent parts in the effective Hamiltonian are canceled with the assistance of a strong classical field, thus the scheme is insensitive to both the thermal field and the cavity decay. The only thing one needs to do is to modulate the interaction time only once.
基金supported by the Doctoral Fund of the Ministry of Education of China (20100091110009)the National Natural Science Foundation of China (Grant Nos. 10878010, 10221001 and 10633040)the National Basic Research Program (973 Program, No. 2007CB815405)
文摘Early-type galaxies (ETGs) are very important for understanding the formation and evolution of galaxies. Recent observations suggest that ETGs are not simply old stellar spheroids as we previously thought. Widespread recent star formation, cool gas and dust have been detected in a substantial fraction of ETGs. We make use of the radial profiles of 9 - r color and the concentration index from the Sloan Digital Sky Survey database to pick out 31 peculiar ETGs with central blue cores. By analyzing the photometric and spectroscopic data, we suggest that the blue cores are caused by star formation activities rather than the central weak active galactic nucleus. From the results of stellar population synthesis, we find that the stellar population of the blue cores is relatively young, spreading from several Myr to less than one Gyr. In 14 galaxies with H I observations, we find that the average gas fraction of these galaxies is about 0.55. The bluer galaxies show a higher gas fraction, and the total star forma- tion rate (SFR) correlates very well with the H I gas mass. The star formation history of these ETGs is affected by the environment, e.g. in the denser environment the H I gas is less and the total SFR is lower. We also discuss the origin of the central star formation of these early-type galaxies.
文摘The asymptotic solution to the scattering problem on a set of small particles, supplemented into homogeneous material, is used for modeling the materials with the desired refractive index. The consideration concerns the case of acoustic scalar scattering and the solution to initial scattering problem is built using an asymptotic approach. The closed form solution is reduced for the scattering problem. This is significant advantage of approach because there is no need to solve the respective system of boundary integral equations. High accuracy of solving the scattering problem is achieved by choosing the optimal parameters of the domain with small particles. The approach allows obtaining an explicit formula for the refractive index of the resulting inhomogeneous material. The numerical calculations show the possibility to get the specific values of refractive index including its negative values.
文摘BACKGROUND: Translocation or transplantation of nerve stem has good effect; however, nervous function of donator is completely lost. If some nerve stem is damaged, sensory tracts are intercepted from the near nerve stem by nutrient vessels to regard as neural graft for transferring and bridging which may repair injured nerve and decrease neural functional loss of donator. OBJECTIVE: To observe anatomical peculiarities on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect, and to investigate its feasibility. DESIGN:Duplicated and measured design.SETTING : Anatomy Department of Medical College affiliated to Nanhua University.MATERIALS: A total of 14 samples of upper limbs were selected from adult unnamed corpse and volunteers.METHODS: The experiment was completed at the Clinical Application Anatomy Laboratory of Medical College affiliated to Nanhua University from September to November 2005. Samples were perfused with red emulsion through artery to observe length, fibrous bands and blood supply of median nerve and ulnar nerve at wrist. Boundary of median nerve at wrist ranged from superficial site between flexor carpi radialis and palmaris Iongus to branch of common palmar digital nerves. Ulnar nerve at wrist ranged from branch of back of the hand to site of common palmar digital nerves. Proximal boundary of the two nerves was crossed from 1/8 to 2/8 region of forearm. Samples of upper limbs from 1 case were selected to simulate operation on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve. MAIN OUTCOME MEASURES: Anatomical peculiarities on sensory tracts of wrist median nerve pedicled with nutrient vessels transferring to bridge wrist ulnar nerve defect. RESULTS: ① The length of wrist median nerves was 7.8 (7.5-8.1) cm. There were 19 to 27 nerve tracts in it and the majority belonged to sensory tracts on the ulnar side, in which non-damaged separated length was about 10.0 cm to 14.0 cm. The third, second and first tracts of cutaneous branches at digital interspace and radialis of thumb arrayed from ulnaris to radialis by turns, and numbers of bands were 6.9, 7.4 and 7.2, respectively. The bands in total were 21.6. Cutaneous branches of palm entered from lateral margin of radialis and were completely separated at wrist. Two-thirds of ulnaris at nerve stem, i.e. the third, second and first tracts of cutaneous branches at digital interspace, were separated, which had little effect on sensation in distribution of median nerve. ② Its nutrient vessels originated from radial arteries about 6.2 (6.1-6.6) cm above radial styloid process were 1.2 (1.1-1.4) mm in outer diameter. The length was 5.7 (5.1-6.1) cm.③ The length of wrist ulnar nerve were 9.4 (8.9-9.7) cm and the number of nervous tract were 14 to 19, in which sensory tracts on the anterior external side were approximately equal to motor and mixed tracts on the posterior internal side in quantity. Sensory tracts were located at radialis of palm and motor tracts were located at ulnaris of back. CONCLUSION :① Character and position of median nerve fibre bundle are clear, and length of non-damage separation of sensory tracts is coincidence with the request of transferring to bridge. ② Summation of the third, second and first tracts of cutaneous branches at digital interspace may be satisfactory to bridge of ulnar nerve at wrist (14-19 bands). ③ This technique has little effect on sensation in distribution of median nerve. Nutrient artery of median nerve locates constantly; journey table is superficial and is easily to find out; caliber of arterial canal is thick; blood supply is plentiful; length of pedicel is suitable for translocation. The sensery tracts of wrist median nerve pedicled with nutrient vessels can be applied as nervous grafts to join injured gap in wrist ulnar nerve.
文摘1 Introduction The observational data of peculiar velocity field of galaxies are important for testing cosmological scenarios. After the pioneer work of Rubin and Ford in 1976, severnl observational results were given by different groups, and many theoretical models were presented. Unfortunately, the theoretical results are inconsistent with observational ones. Recently, Ostriker et al. have presented the new concept (cosmic Mach number) and given calculated results. In this note, we will detail calculations of peculiar velocities and cosmic Mach numbers by using some acceptable assumptions.
基金Project supported by the National Natural Science Foundation of China.
文摘The peculiar velocity of quasars is among the data needing extremely to be sought out inthe observational cosmology. Thos paper proposes a method for determining an upper limitto the peculiar velocity of quasars by means of a statistical analysis of quasar pairs. A pre-liminary conclusion is that the peculiar velocity in the direction along the line joining thetwo quasars in a pair does not exceed, on average, 1000 km/s.
文摘To the Editor: With interest we read the article by Yu et al[1] about a retrospective study of 13 pediatric patients with Leigh syndrome from a single center in China collected over a period of 17 years. The authors concluded that patients with ophthalmoplegia, muscle weakness, ataxia, and respiratory insufficiency should be screened for mutations in genes located on the mtDNA.[1] Patients with suspected Leigh syndrome are recommended to undergo determination of cerebrospinal fluid (CSF) lactate and cerebral imaging.[1] We have the following comment and concerns.
基金supported by MOE Tier 1 project at National University of Singapore(No.A-0005235-01-00).
文摘Gas distribution function plays a crucial role in the description of gas flows at the mesoscopic scale.In the presence of non-equilibrium flow,the distribution function loses its rotational symmetricity,making the mathematical derivation difficult.From both the Chapman-Enskog expansion and the Hermite polynomial expansion(Grad’s method),we observe that the non-equilibrium effect is closely related to the peculiar velocity space(C).Based on this recognition,we propose a new methodology to construct the non-equilibrium distribution function from the perspective of polynomial expansion in the peculiar velocity space of molecules.The coefficients involved in the non-equilibrium distribution function can be exactly determined by the compatibility conditions and the moment relationships.This new framework allows constructing non-equilibrium distribution functions at any order of truncation,and the ones at the third and the fourth order have been presented in this paper for illustration purposes.Numerical validations demonstrate that the new method is more accurate than the Grad’s method at the same truncation error for describing non-equilibrium effects.Two-dimensional benchmark tests are performed to shed light on the applicability of the new method to practical engineering problems.