Density functional theory (DFT) was used to calculate molecular descriptors (properties) for 12 fluoro-quinolone with anti-S.pneumoniae activity. Principal component analysis (PCA) and hierarchical cluster analy...Density functional theory (DFT) was used to calculate molecular descriptors (properties) for 12 fluoro-quinolone with anti-S.pneumoniae activity. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to reduce dimensionality and investigate in which variables should be more effective for classifying fluoroquinolones according to their degree of an-S.pneumoniae activity. The PCA results showed that the variables ELUMO, Q3, Q5, QA, logP, MR, VOL and △EHL of these compounds were responsible for the anti-S.pneumoniae activity. The HCA results were similar to those obtained with PCA.The methodologies of PCA and HCA provide a reliable rule for classifying new fluoroquinolones with antiS.pneumoniae activity. By using the chemometric results, 6 synthetic compounds were analyzed through the PCA and HCA and two of them are proposed as active molecules with anti-S.pneumoniae, which is consistent with the results of clinic experiments.展开更多
In the harsh environment where n ode density is sparse, the slow-moving nodes cannot effectively utilize the encountering opportunities to realize the self-organized identity authentications, and do not have the chanc...In the harsh environment where n ode density is sparse, the slow-moving nodes cannot effectively utilize the encountering opportunities to realize the self-organized identity authentications, and do not have the chance to join the network routing. However, considering m ost of the communications in opportunistic networks are caused by forwarding operations, there is no need to establish the complete mutual authentications for each conversation. Accordingly, a novel trust management scheme is presented based on the information of behavior feedback, in order to complement the insufficiency of identity authentications. By utilizing the certificate chains based on social attributes, the mobile nodes build the local certificate graphs gradually to realize the web of "Identity Trust" relationship. Meanwhile, the successors generate Verified Feedback Packets for each positive behavior, and consequently the "Behavior Trust" relationship is formed for slow-moving nodes. Simulation result shows that, by implementing our trust scheme, the d elivery probability and trust reconstruction ratio can be effectively improved when there are large numbers of compromised nodes, and it means that our trust management scheme can efficiently explore and filter the trust nodes for secure forwarding in opportunistic networks.展开更多
Existing location privacy- preserving methods, without a trusted third party, cannot resist conspiracy attacks and active attacks. This paper proposes a novel solution for location based service (LBS) in vehicular a...Existing location privacy- preserving methods, without a trusted third party, cannot resist conspiracy attacks and active attacks. This paper proposes a novel solution for location based service (LBS) in vehicular ad hoc network (VANET). Firstly, the relationship among anonymity degree, expected company area and vehicle density is discussed. Then, a companion set F is set up by k neighbor vehicles. Based on secure multi-party computation, each vehicle in V can compute the centroid, not revealing its location to each other. The centroid as a cloaking location is sent to LBS provider (P) and P returns a point of interest (POI). Due to a distributed secret sharing structure, P cannot obtain the positions of non-complicity vehicles by colluding with multiple internal vehicles. To detect fake data from dishonest vehicles, zero knowledge proof is adopted. Comparing with other related methods, our solution can resist passive and active attacks from internal and external nodes. It provides strong privacy protection for LBS in VANET.展开更多
AIM: To investigate the effects of sleeve gastrectomy on adipose tissue infiltration and lectin-like oxidized low density lipoprotein receptor-1 (LOX-1) expression in rat aortas. METHODS: Twenty-four rats were randomi...AIM: To investigate the effects of sleeve gastrectomy on adipose tissue infiltration and lectin-like oxidized low density lipoprotein receptor-1 (LOX-1) expression in rat aortas. METHODS: Twenty-four rats were randomized into three groups: normal chow (control), high fat diet (HD) and high fat diet with sleeve gastrectomy (SG). After surgery, the HD and SG groups were fed a high fat diet. Animals were sacrificed and plasma high density lipoprotein (HDL) and low density lipoprotein (LDL) levels were determined. LOX-1 protein and LOX-1 mRNA expression was also measured. Aortas were stained with Nile red to visualize adipose tissue. RESULT: Body weights were higher in the HD group compared to the other groups. HDL levels in control,HD, and SG groups were 32.9 ± 6.2 mg/dL, 43.4 ± 4.0 mg/dL and 37.5 ± 4.3 mg/dL, respectively. LDL levels in control, HD, and SG groups were 31.8 ± 4.5 mg/dL, 53.3 ± 5.1 mg/dL and 40.5 ± 3.7 mg/dL, respectively. LOX-1 protein and LOX-1 mRNA expression was greater in the HD group versus the other groups. Staining for adipose tissue in aortas was greater in the HD group in comparison to the other groups. Thus, a high fat diet elevates LOX-1 protein and mRNA expression in aorta. CONCLUSION: Sleeve gastrectomy decreases plasma LDL levels, and downregulates LOX-1 protein and mRNA expression.展开更多
The results of the three-year researches which had the purpose to establish an optimum depth of seeding at sowing and rational norm of seeding of red beetroot seeds at under-winter sowing in conditions of mid-loamy ty...The results of the three-year researches which had the purpose to establish an optimum depth of seeding at sowing and rational norm of seeding of red beetroot seeds at under-winter sowing in conditions of mid-loamy typical grey soils of the central climatic zone of Uzbekistan are stated in article. The researches were spent at statement of field experiences in quadruple frequency with the area of a registration allotment 10 M^-1. Crops were carried out in the first decade of December against mulching surfaces of ridges by humus and without mulching. Crops were carried out on ridges in width of 70 sm tape-two-lined with distance between tapes of 50 sm, between lines-20 sm and distance between plants in a line of 12-13 sm, at density of standing of 228-230 thousand plants/hectares. Experiences were spent with zoned in Uzbekistan multi-seedling grade of a red beetroot "Bordo 237". Experiences were accompanied by phenological supervision, biometric accounts, the account of field germination of seeds, density of standing of plants and definition of size and quality of a crop. Results of researches were exposed to the statistical analysis by a dispersive method. It has been revealed that at under-winter sowing of a red beetroot the effective way providing acceleration of shoots occurrence, formations of high-grade density of standing and increase of productivity of root crops is mulching the surfaces of ridges by humus. It is defined that optimum depth of seeding at sowing both at application of mulching and without it is the depth of seeding 4 sm. It is established that the most rational norm of seeding of the seeds, providing high-grade density of standing, is at cultivation with application of mulching 8 kg/ha, and at cultivation without mulching 8-10 kg/ha. Application of mulching the surfaces of ridges by humus, depths of seeding of 4 sm and norms of seeding of seeds of 8-10 kg/ha in conditions of under-winter sowing in comparison with cultivation without mulching and depth of seeding 2 sm and norms of seeding of 6 kg/ha provides an acceleration of receipt of fresh production of a red beetroot for 12-14 days and considerably raises root crops productivity. Application of agro receptions improved by us is the important reserve of acceleration of receipt of red beetroot early production and increase of its manufacture.展开更多
In recent years,three-dimensional topological insulators(3DTI) as a novel state of quantum matter have become a hot topic in the fields of condensed matter physics and materials sciences.To fulfill many spectacularly ...In recent years,three-dimensional topological insulators(3DTI) as a novel state of quantum matter have become a hot topic in the fields of condensed matter physics and materials sciences.To fulfill many spectacularly novel quantum phenomena predicted in 3DTI,real host materials are of crucial importance.In this review paper,we first introduce general methods of searching for new 3DTI based on the density-functional theory.Then,we review the recent progress on materials realization of 3DTI including simple elements,binary compounds,ternary compounds,and quaternary compounds.In these potential host materials,some of them have already been confirmed by experiments while the others are not yet.The 3DTI discussed here does not contain the materials with strong electron-electron correlation.Lastly,we give a brief summary and some outlooks in further studies.展开更多
In the present work,the optical properties of a GaAs quantum wire with equilateral triangle cross section are studied.For this purpose,we use analytical expressions for optical properties obtained by the compact-densi...In the present work,the optical properties of a GaAs quantum wire with equilateral triangle cross section are studied.For this purpose,we use analytical expressions for optical properties obtained by the compact-density matrix formalism.Here,we investigate the intersubband optical absorption coefficients and refractive index changes as a function of the triangle side(L) and the incident optical intensity(I).According to the obtained results,it is found that:(i) The total refractive index changes increase and shift towards lower energies when the triangle side increases.(ii) The total absorption coefficient decreases as the triangle side increases.Also,the resonance peak shifts towards lower energies by increasing the triangle side.展开更多
We demonstrate experimentally the population inversion between 7S1/2 and 6P3/2 levels of cesium in thermal cesium cell with a 455.5 nm pumping laser.We calculate the relative population probabilities at each level the...We demonstrate experimentally the population inversion between 7S1/2 and 6P3/2 levels of cesium in thermal cesium cell with a 455.5 nm pumping laser.We calculate the relative population probabilities at each level theoretically with the density matrix method.In a steady state,5.8% atoms are at 7S1/2 level and 2.9% at 6P3/2 level,which builds up the population inversion between the two levels.We obtain the fluorescence spectra produced in thermal cesium cell in our experiment.The measured relative intensity of each available fluorescence spectral line in the experiment agrees very well with the theoretical result.The demonstrated population inversion between 7S1/2 and 6P3/2 levels can be used to construct an active optical clock of four-level system with a wavelength of 1469.9 nm.展开更多
基金This work was supported by National Nature Science Foundation of China and China Academy of Engineering Physics (No. 10376021) Provincial National Science Foundation of He'nan (No. 2004601107).
文摘Density functional theory (DFT) was used to calculate molecular descriptors (properties) for 12 fluoro-quinolone with anti-S.pneumoniae activity. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to reduce dimensionality and investigate in which variables should be more effective for classifying fluoroquinolones according to their degree of an-S.pneumoniae activity. The PCA results showed that the variables ELUMO, Q3, Q5, QA, logP, MR, VOL and △EHL of these compounds were responsible for the anti-S.pneumoniae activity. The HCA results were similar to those obtained with PCA.The methodologies of PCA and HCA provide a reliable rule for classifying new fluoroquinolones with antiS.pneumoniae activity. By using the chemometric results, 6 synthetic compounds were analyzed through the PCA and HCA and two of them are proposed as active molecules with anti-S.pneumoniae, which is consistent with the results of clinic experiments.
基金supported by the Program for Changjiang Scholars and Innovative Research Team in University (IRT1078)the Key Program of NSFC-Guangdong Union Foundation (U1135002)+3 种基金the Major national S&T program(2012ZX03002003)the Fundamental Research Funds for the Central Universities(JY10000903001)the National Natural Sci ence Foundation of China (Grant No. 61363068, 61100233)the Natural Science Foundation of Shaanxi Province (Grant No. 2012JM8030, 2011JQ8003)
文摘In the harsh environment where n ode density is sparse, the slow-moving nodes cannot effectively utilize the encountering opportunities to realize the self-organized identity authentications, and do not have the chance to join the network routing. However, considering m ost of the communications in opportunistic networks are caused by forwarding operations, there is no need to establish the complete mutual authentications for each conversation. Accordingly, a novel trust management scheme is presented based on the information of behavior feedback, in order to complement the insufficiency of identity authentications. By utilizing the certificate chains based on social attributes, the mobile nodes build the local certificate graphs gradually to realize the web of "Identity Trust" relationship. Meanwhile, the successors generate Verified Feedback Packets for each positive behavior, and consequently the "Behavior Trust" relationship is formed for slow-moving nodes. Simulation result shows that, by implementing our trust scheme, the d elivery probability and trust reconstruction ratio can be effectively improved when there are large numbers of compromised nodes, and it means that our trust management scheme can efficiently explore and filter the trust nodes for secure forwarding in opportunistic networks.
基金the National Natural Science Foundation of China,by the Natural Science Foundation of Anhui Province,by the Specialized Research Fund for the Doctoral Program of Higher Education of China,the Fundamental Research Funds for the Central Universities
文摘Existing location privacy- preserving methods, without a trusted third party, cannot resist conspiracy attacks and active attacks. This paper proposes a novel solution for location based service (LBS) in vehicular ad hoc network (VANET). Firstly, the relationship among anonymity degree, expected company area and vehicle density is discussed. Then, a companion set F is set up by k neighbor vehicles. Based on secure multi-party computation, each vehicle in V can compute the centroid, not revealing its location to each other. The centroid as a cloaking location is sent to LBS provider (P) and P returns a point of interest (POI). Due to a distributed secret sharing structure, P cannot obtain the positions of non-complicity vehicles by colluding with multiple internal vehicles. To detect fake data from dishonest vehicles, zero knowledge proof is adopted. Comparing with other related methods, our solution can resist passive and active attacks from internal and external nodes. It provides strong privacy protection for LBS in VANET.
基金Supported by A Grant from the National Natural Science Foundation of China, No. 81000158the Special Fund for Technology of Liaoning Province, No. L2010591
文摘AIM: To investigate the effects of sleeve gastrectomy on adipose tissue infiltration and lectin-like oxidized low density lipoprotein receptor-1 (LOX-1) expression in rat aortas. METHODS: Twenty-four rats were randomized into three groups: normal chow (control), high fat diet (HD) and high fat diet with sleeve gastrectomy (SG). After surgery, the HD and SG groups were fed a high fat diet. Animals were sacrificed and plasma high density lipoprotein (HDL) and low density lipoprotein (LDL) levels were determined. LOX-1 protein and LOX-1 mRNA expression was also measured. Aortas were stained with Nile red to visualize adipose tissue. RESULT: Body weights were higher in the HD group compared to the other groups. HDL levels in control,HD, and SG groups were 32.9 ± 6.2 mg/dL, 43.4 ± 4.0 mg/dL and 37.5 ± 4.3 mg/dL, respectively. LDL levels in control, HD, and SG groups were 31.8 ± 4.5 mg/dL, 53.3 ± 5.1 mg/dL and 40.5 ± 3.7 mg/dL, respectively. LOX-1 protein and LOX-1 mRNA expression was greater in the HD group versus the other groups. Staining for adipose tissue in aortas was greater in the HD group in comparison to the other groups. Thus, a high fat diet elevates LOX-1 protein and mRNA expression in aorta. CONCLUSION: Sleeve gastrectomy decreases plasma LDL levels, and downregulates LOX-1 protein and mRNA expression.
文摘The results of the three-year researches which had the purpose to establish an optimum depth of seeding at sowing and rational norm of seeding of red beetroot seeds at under-winter sowing in conditions of mid-loamy typical grey soils of the central climatic zone of Uzbekistan are stated in article. The researches were spent at statement of field experiences in quadruple frequency with the area of a registration allotment 10 M^-1. Crops were carried out in the first decade of December against mulching surfaces of ridges by humus and without mulching. Crops were carried out on ridges in width of 70 sm tape-two-lined with distance between tapes of 50 sm, between lines-20 sm and distance between plants in a line of 12-13 sm, at density of standing of 228-230 thousand plants/hectares. Experiences were spent with zoned in Uzbekistan multi-seedling grade of a red beetroot "Bordo 237". Experiences were accompanied by phenological supervision, biometric accounts, the account of field germination of seeds, density of standing of plants and definition of size and quality of a crop. Results of researches were exposed to the statistical analysis by a dispersive method. It has been revealed that at under-winter sowing of a red beetroot the effective way providing acceleration of shoots occurrence, formations of high-grade density of standing and increase of productivity of root crops is mulching the surfaces of ridges by humus. It is defined that optimum depth of seeding at sowing both at application of mulching and without it is the depth of seeding 4 sm. It is established that the most rational norm of seeding of the seeds, providing high-grade density of standing, is at cultivation with application of mulching 8 kg/ha, and at cultivation without mulching 8-10 kg/ha. Application of mulching the surfaces of ridges by humus, depths of seeding of 4 sm and norms of seeding of seeds of 8-10 kg/ha in conditions of under-winter sowing in comparison with cultivation without mulching and depth of seeding 2 sm and norms of seeding of 6 kg/ha provides an acceleration of receipt of fresh production of a red beetroot for 12-14 days and considerably raises root crops productivity. Application of agro receptions improved by us is the important reserve of acceleration of receipt of red beetroot early production and increase of its manufacture.
基金supported by the National Basic Research Program of China (Grants No.2011CBA00100)the National Natural Science Foundation of China(Grant Nos.10974231 and 11174337)
文摘In recent years,three-dimensional topological insulators(3DTI) as a novel state of quantum matter have become a hot topic in the fields of condensed matter physics and materials sciences.To fulfill many spectacularly novel quantum phenomena predicted in 3DTI,real host materials are of crucial importance.In this review paper,we first introduce general methods of searching for new 3DTI based on the density-functional theory.Then,we review the recent progress on materials realization of 3DTI including simple elements,binary compounds,ternary compounds,and quaternary compounds.In these potential host materials,some of them have already been confirmed by experiments while the others are not yet.The 3DTI discussed here does not contain the materials with strong electron-electron correlation.Lastly,we give a brief summary and some outlooks in further studies.
文摘In the present work,the optical properties of a GaAs quantum wire with equilateral triangle cross section are studied.For this purpose,we use analytical expressions for optical properties obtained by the compact-density matrix formalism.Here,we investigate the intersubband optical absorption coefficients and refractive index changes as a function of the triangle side(L) and the incident optical intensity(I).According to the obtained results,it is found that:(i) The total refractive index changes increase and shift towards lower energies when the triangle side increases.(ii) The total absorption coefficient decreases as the triangle side increases.Also,the resonance peak shifts towards lower energies by increasing the triangle side.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10874009 and 11074011)
文摘We demonstrate experimentally the population inversion between 7S1/2 and 6P3/2 levels of cesium in thermal cesium cell with a 455.5 nm pumping laser.We calculate the relative population probabilities at each level theoretically with the density matrix method.In a steady state,5.8% atoms are at 7S1/2 level and 2.9% at 6P3/2 level,which builds up the population inversion between the two levels.We obtain the fluorescence spectra produced in thermal cesium cell in our experiment.The measured relative intensity of each available fluorescence spectral line in the experiment agrees very well with the theoretical result.The demonstrated population inversion between 7S1/2 and 6P3/2 levels can be used to construct an active optical clock of four-level system with a wavelength of 1469.9 nm.