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Ab initio theory of the negatively charged boron vacancy qubit in hexagonal boron nitride

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npj Computational Materials 2020年第1期6卷 1332-1337页

作者： Viktor Ivády Gergely Barcza GergőThiering Song Li Hanen Hamdi Jyh-Pin Chou örs legeza Adam Gali Wigner Research Centre for Physics PO Box 49Budapest 1525Hungary Department of Physics Chemistry and BiologyLinköping University58183 LinköpingSweden J.HeyrovskýInstitute of Physical Chemistry Academy of Sciences of the Czech RepublicDolejškova 318223 Prague 8Czech Republic Department of Mechanical Engineering City University of Hong KongKowloon TongHong KongChina Department of Atomic Physics Budapest University of Technology and EconomicsBudafokiút 8.Budapest 1111Hungary

Highly correlated orbitals coupled with phonons in two-dimension are identified for paramagnetic and optically active boron vacancy in hexagonal boron nitride by first principles methods which are responsible for recently observed optically detected magnetic resonance ***,we report ab initio analysis of the correlated electronic structure of this center by density matrix renormalization group and Kohn-Sham density functional theory *** establishing the nature of the bright and dark states as well as the position of the energy levels,we provide a complete description of the magneto-optical properties and corresponding radiative and non-radiative routes which are responsible for the optical spin polarization and spin dependent luminescence of the *** findings pave the way toward advancing the identification and characterization of room temperature quantum bits in two-dimensional solids.

关键词： boron hexagonal vacancy

Diffusion of Hydrogen in Amorphous NiCrFeSiB Alloy

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Journal of Materials Science & Technology 1996年第1期12卷 15-18页

作者： Zuo, Y Yang, B Xu, rs Dept. of Applied Chemistry Beijing University of Chemical Technology Beijing 100029 China

The diffusion of hydrogen in amorphous NiCrFeSiB alloy has been studied by electrochemical method. In the temperature range of 20 similar to 50 degrees C, diffusion coefficient of hydrogen in the alloy follows the equation: D(cm(2)/s) = 9.27x10(-8) exp(-53.4 kJ/RT). At room temperature the diffusion coefficient D and the solubility C-0 are 6.125 x 10(-12) cm(2)/s and 0.007 mol/cm(3), respectively. When As2O3 is added into the cathodic solution or the charging current density is increased, the diffusion coefficient and solubility increase, and the diffusion activation energy decreases. The influence of amorphous structure on diffusion and solution of hydrogen is discussed.

关键词： Nickel alloys

Prevalence,intensity of infection and risk factors of urinary schistosomiasis in preschool and school aged children in Guma Local Government Area,Nigeria

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Asian Pacific Journal of Tropical Medicine 2014年第1期7卷 34-39页

作者： EU Amuta rs Houmsou Department of Biological Sciences University of Agriculture Makurdip.M.B 2373 MakurdiBenue StateNigeria. Department of Biological Sciences Taraba State UniversityJalingoP.M.B 1167 JalingoTaraba StateNigeria

Objective:To determine the prevalence and intensity of infection and the risk factors associated with urinary schistosomiasis in pre—school and school aged children in Cuma Local Government Area of Benue State,***:Urine filtration technique using polycarbonate membrane filters was employed to process urine specimens and to determine presence of Schistosoma haematobium eggs in *** were also administered to children to collect information on socio-demographic data and water-contact ***:An overall prevalence of 55.0%(165/300)was recorded out of the 300 urine samples *** of infection varied between 36.0%-64.0%with a significant difference(X^2=11.59,P=0.041)between the different communities *** were more infected(60.6%,103/170)than females(47.7%,62/130)with a significant difference(X^2=4.95,P=0.026).The age-related prevalence showed higher prevalence(70.5%,36/52)in the 11-15 year old children than that in the 1-5 year old ones(44.9%,53/118).A significant difference was observed in the prevalence between the age groups(X^2=10.56,P=0.014).The prevalence of light intensity of infection(1-49 eggs/10 mL of urine)(86.6%)was significantly higher than that of heavy intensity of infection(5=50 eggs/10 mL of urine)(13.3%)in the area(t=16.48,P=0.000).Water contact activities of the children revealed that children that were involved in irrigation and those that went swimming in water bodies were observed to be at higher risk of becoming infected with urinary schistosomiasis in the area with odd ratios(risk factors)of 2.756(1.334-5.693)and 2.366(1.131-4.948)respectively at P<0.05 ***:The study revealed the hyperendemicily of urinary schistosomiasis in the preschool and school aged children in Guma Local Government *** is therefore recommended that praziquantel should be administered to children in the area and systematic epidemiological studies should be undertaken in the whole Local Government Ar

关键词： Hyperendemic Schistosomiasis Urine Prevalence Intensity Risk factor

Comparison between phylogeny of introns and exons in primates

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Chinese Science Bulletin 1999年第21期44卷 1940-1946页

作者： Wang, N Chen, rs Chinese Acad Sci Prot Engn Lab Inst Biophys Beijing 100101 Peoples R China

Introns and exons of 7 genes ( epsilon globin, gamma-1 globin, gamma-2 globin, delta globin, beta globin, Immunoglobulin and prepro-insulin) in primates have been separated out and used to infer phylogeny respectively. For each gene, results based on these two parts have been compared and showed that: ( i ) the topology of introns is almost

关键词： phylogeny inference intron substitution rate molecular evolution.

Cytoprotective,antihyperglycemic and phytochemical properties of Cocos nucifera(L.) inflorescence

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Asian Pacific Journal of Tropical Medicine 2013年第10期6卷 804-810页

作者： rs Renjith AM Chikku T Rajamohan Department of Biochemistry University of KeralaThiruvananthapuram-695581KeralaIndia

Objective:To analyze the eytoproteetive and antidiabetic activities as well as phytochemical composition of the immature inflorescence of Cocas nucifera belonging to the Arecaceae ***:The phytochemical screening of inflorescence was done to determine the major constituents present in Cocos nucifera *** free radical scavenging potential of inflorescence extracts were evaluated using in vitro radical scavenging assay ***:The phytochemical analyses on inflorescence showed the presence of phenolic compounds,*** and *** macronutrient analyses,on the other hand,showed the presence of carbohydrate,proteins and *** of the methanol extract of coconut inflorescence to the diabetic rats showed dose dependent reduction in *** cytoprotective property of coconut inflorescence was evidenced from the acute toxicological *** levels of serum aspartate aminotransferase,alanine aminotransferase,and alkaline phosphatase were significantly decreased in the diabetic rats treated with inflorescence when compared with the diabetic control ***:The results obtained from the present study apparently proved the non-toxic nature and the eytoproteetive and antihyperglycemic properties of coconut inflorescence.

关键词： Antihyperglycemic Coconut inflorescence Cytoprotective property Phenolic compound Phytochemical Stroptozotocin

Central nervous system activity of Illicium verum fruit extracts

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Asian Pacific Journal of Tropical Medicine 2013年第11期6卷 869-875页

作者： Divya Chouksey Neeraj Upmanyu rs Pawar Phytochemistry and Pharmacognosy Division VNS Institute of PharmacyNeelbudBHOPALM.P.India R.K.D.F.College of Pharmacy Hoshangabad RoadBhopalM.P.-462047.India

Objective:To research the acute toxicity of Illicium verum(***)fruit extracts and its action on central nervous ***:The TLC and HPTLC techniques were used as fingerprints to determine the chemical components present in *** albino rats and mice were utilized for *** powdered material was successively extracted with n-hexane,ethyl acetate and methanol using a Soxhlet *** toxicity studies were performed as per OECD *** CNS activity was evaluated on parameters of general behavior,sleeping pattern,locomotor activity,anxicty and myocoordination *** animals were trained for seven days prior to experiments and the divided into five groups with six animals in *** drug was administered by intraperitoneal route according to body *** dosing was done as prescribed in each ***:Toxicity studies reported 2 000 mg/kg as toxicological dose and 1/10 of the same dose was taken as therapeutic dose Intraperitoneal injection of all extracts at dose of 200 mg prolonged phenobarbitone induced sleeping time,produced alteration in general behavior pattern,reduced locomotor activity and produced anxiolytic effects but the extracts do not significantly alter muscles coordination *** three extracts of *** at the dose of 200 mg,methanol extract was found to produce more prominent effects,then hexane and ethylacetate ***:The observation suggested that the extracts of I. verum possess potent CNS depressant action and anxiolytic effect without interfering with motor coordination.

关键词： Illicium verum TLC HPTLC Anxiolytic CNS depressant

An integrative insight into the synsacral canal of fossil and extant Antarctic penguins

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Integrative Zoology 2023年第2期18卷 237-253页

作者： Piotr JADWISZCZAK Anders SVENSSON-MARCIAL Thomas MÖrs Faculty of Biology University of BialystokBialystokPoland Department of Clinical Science Intervention and Technology at Karolinska InstituteStockholmSweden Department of Palaeobiology Swedish Museum of Natural HistoryStockholmSweden

The lumbosacral-canal system in birds most likely operates as a sense organ involved in the control of balanced walking and perching,but our knowledge of it is superﬁ*** constitute interesting objects for the study of this system due to their upright walking,but only the Humboldt penguin,Spheniscus humboldti,and some incomplete fossil penguin synsacra have been studied in this ***,we give an integrative comparative in-sight into the synsacral canal of extant Emperor penguin,Aptenodytes forsteri,Adelie penguin,Pygoscelis adeliae,and Eocene giant Anthropornis and/or Palaeeudyptes Antarctic penguins,using computed tomography imaging and associated data-extraction methodologies,complemented by analytical approaches ranging from geometric morphometrics to modularity,curvature,and wavelet *** document that the variability in the number of synsacro-lumbar vertebrae is evolutionarily conserved,and all studied synsacra possess osteological correlates of the lumbosacral-canal *** also found that Eocene and extant Antarctic penguins were separable on the basis of the main direction of the shape-related(size-independent)variability within said system,and *** was unique in the entire studied set in terms of the relative cranial shift of this compound ***,we suggest that the evolutionary processes,shaping both the terrestrial posture and gait,were responsible,in extant penguins,for the increased simplicity and stability of the synsacral canal cross-sectional periodic patterns,as well as pave the way for the lumbosacral-canal system modularity characterized by reduced atomization/complexity.

关键词： Antarctica Cenozoic lumbosacral canals Sphenisciformes synsacrum

Research on Characteristics of Density Current Under the Action of Waves

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China Ocean Engineering 1997年第1期12卷 69-78页

作者： Li, DS Shen, Y Ren, rs Chen, Y HOHAI UNIV NANJING 210098PEOPLES R CHINA

In this paper, the characteristics of density current under the action of waves are described with the help of flume experiment and theoretical analysis. The study shows that turbid water under the action of the waves can present three types of motion, i. e. significant stratification, fragile stratification and strong mixing. The motion gf turbid;,ater presents significant stratification when (H/D)/root Delta rho/rho less than or equal to 4.5, generally this state is known as density current. The formulas of motion velocity, thickness, and discharge of density current moving on horizontal bottom are derived by use of basic equations such as momemtum equation, equation of energy conservation and continuity equation of fluid. The time-average velocity and the thickness of density current under the action of waves have a relationship with such parameters as relative density (Delta rho/rho), wave height (H), and water depth (D). When these parameters are determined, the time-average thickness and motion velocity of density current are also determined. The relative thickness of density current (D-t/D) decreases with the increase of Delta rho/rho and increases with the increase of H/D. On the other hand, the motion velocity of density current increases with the increase of Delta rho/rho and decreases with the increase of the relative thickness (D-t/D) of density current. It is shown that the calculated results are in agreement with those of the flume experiment.

关键词： turbid current density current gravity current wave action motion velocity thickness

Salmonella typhi infection in a tertiary institution in Nasarawa State,Nigeria

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Asian Pacific Journal of Tropical Medicine 2011年第2期4卷 137-139页

作者： Ishaleku D Sar TT Houmsou rs Microbiology Unit Department of Biological SciencesNasarawa State University KeffiP.M.B 1022 KeffiNigeria Department of Biological Sciences University of MkarMkarP.M.B 017GbokoBenue StateNigeria Applied Zoology Unit Department of Biological SciencesTaraba State UniversityJalingoP.M.B 1167 JalingoTaraba StateNigeria

Objective:To evaluate the prevalence of Sabmonella typhi(***) among subjects attending College of Education Health Clinic,Akwanga,Nasarawa state from the year.2005 to 2007 and to recommend some preventive measures to the ***:Blood samples were tested for infection using the widal ***:Out of the 793 patients examined,579(73.0%) were positive with 174(30.05%),254(43.86%) and 151(26.07%) for the years 2005,2006 and 2007 respectively. The age range with the highest prevalence of infection for the period was 21-30 with 207(35.75%) followed by 31-40 year group with 133(22.97%).Chi-square analysis showed no significant difference in infection between males and females(P>0.05).Conclusions:The results of this study provide a useful guide in the formulation of *** control measures in tertiary institutions in the State and also help to check the spread of the pathogen in the general population.

关键词： Salmonella typhi Infection Tertiary institution Nasarawa State