This study investigates the multifield vibration behavior of a porosity-dependent bidirectional functionally graded piezoelectric nano-plate(FGPN)subjected to hygrothermal and thermoelectric loading.The material compo...This study investigates the multifield vibration behavior of a porosity-dependent bidirectional functionally graded piezoelectric nano-plate(FGPN)subjected to hygrothermal and thermoelectric loading.The material composition is defined by sigmoid and power-law distributions along both transverse and axial directions,accommodating even,uneven,and symmetrically centered porosity patterns.The model incorporates nonclassical elasticity theory and von Kármán nonlinear strains,with the governing equations formulated using a modified first-order shear deformation theory and derived through the energy principle.A higher-order finite element formulation,coupled with a modified Newton-Raphson procedure,ensures robust computational accuracy,validated through convergence tests.The analysis delves into the influence of porosity distribution,bidirectional material variations,non-uniform thickness,thickness ratios,variable elastic foundations,and boundary conditions on vibrational behavior.Additionally,the study explores the interplay of hygrothermal and electrical loading conditions in diverse configurations.The findings highlight the pivotal role of bidirectional material gradation in shaping the vibrational response of porous FGPN structures,offering valuable insights for the design of nano-plates in hygrothermal and thermoelectric applications.展开更多
Objective:To detect extended spectrumβ-lactamase(ESBL)and determine its prevalence in various clinical samples collected from Dehradun City Hospital.Methods:The samples were first cultured in MacConkey’s agar plates...Objective:To detect extended spectrumβ-lactamase(ESBL)and determine its prevalence in various clinical samples collected from Dehradun City Hospital.Methods:The samples were first cultured in MacConkey’s agar plates by streak plate method,then identified by Gram staining and biochemical tests.The isolated bacterial strains were then tested for antibiotic susceptibility by Kirby-Bauer method.The ESBL detection is then carried out by double disc diffusion method.Results:Off the 56 samples cultured,21 strains were identified which were six Escherichia coli(E.coli),six Klebsiella,four Proteus,four Pseudomonas aeruginosa(P.aeruginosa)and only one Acinetobacter.Eight out of 21(38.1%)strains including three of E.coli,three of Klebsiella and two of P.aeruginosa,were found to be resistance to all five antibiotics(piperacillin,amikacin,ampicillin,gentamicin,and ciprofloxacin).Initial screening using four antibiotics(cefotaxime,ceftazidime,aztreonam and ceftriaxone)and the final confirmatory test using ceftazidime/clavulanic acid and ceftazidime alone showed that 19.05%of all strains isolated were ESBL producers.Individually,16.67%E.coli,16.67%Klebsiella pneumoniae,25%P.aeruginosa and 100%Acinetobacter were found to be ESBL producers.Conclusions:Antibiotic resistance by ESBL has become a major risk factor worldwide,therefore routine checkup and accordingly prescription are suggested.展开更多
Objective:To study chemical constituents of essential oil of the roots of Nardostachys jatamansi found in different regions of Nepal and also to investigate phytochemical as well as antimicrobial activity of the sampl...Objective:To study chemical constituents of essential oil of the roots of Nardostachys jatamansi found in different regions of Nepal and also to investigate phytochemical as well as antimicrobial activity of the sample with high yield of essential oil.Methods:The essential oils of roots of plant from five different regions were extracted by hydro-distillation and analyzed by gas chromatography-mass spectroscopy for their chemical constituents.The root samples were also subjected to hydro-alcoholic extraction and then fractionated with hexane,chloroform,n-butanol and water so as to perform phytochemical screening and antimicrobial activity.Results:The essential oil yield of sample from Jumla was found to be the highest followed by a sample from Nepalgunj,Surkhet and Kathmandu whereas that of sample from Dharan was found to be the lowest.Gas chromatography-mass spectrometer analysis of essential oil of five samples showed that“2-beta pinene”appeared dominated in three samples,namely,6VJ Nepalgunj,9VJA Jumla and 10VJ Surkhet.Similarly“alkohol aus neoclovenoxid”in 8VJ Dharan and“methoxy phenyloxime”in 13VJA Kathmandu was found to be present in the highest amount.Phytochemical screening of different fractions of sample 9VJA Jumla showed the presence of alkaloids,terpenoids,glycosides,proteins and amino acids,and carbohydrates etc.Antimicrobial susceptibility test of same fractions showed the n-butanol fraction potent against all pathogens and most affected one was Escherichia coli.Conclusions:Our study suggests that the essential oil of Nardostachys jatamansi found in Nepal contains more than 80 compounds with their quality and quantity differing from place to place.展开更多
文摘This study investigates the multifield vibration behavior of a porosity-dependent bidirectional functionally graded piezoelectric nano-plate(FGPN)subjected to hygrothermal and thermoelectric loading.The material composition is defined by sigmoid and power-law distributions along both transverse and axial directions,accommodating even,uneven,and symmetrically centered porosity patterns.The model incorporates nonclassical elasticity theory and von Kármán nonlinear strains,with the governing equations formulated using a modified first-order shear deformation theory and derived through the energy principle.A higher-order finite element formulation,coupled with a modified Newton-Raphson procedure,ensures robust computational accuracy,validated through convergence tests.The analysis delves into the influence of porosity distribution,bidirectional material variations,non-uniform thickness,thickness ratios,variable elastic foundations,and boundary conditions on vibrational behavior.Additionally,the study explores the interplay of hygrothermal and electrical loading conditions in diverse configurations.The findings highlight the pivotal role of bidirectional material gradation in shaping the vibrational response of porous FGPN structures,offering valuable insights for the design of nano-plates in hygrothermal and thermoelectric applications.
文摘Objective:To detect extended spectrumβ-lactamase(ESBL)and determine its prevalence in various clinical samples collected from Dehradun City Hospital.Methods:The samples were first cultured in MacConkey’s agar plates by streak plate method,then identified by Gram staining and biochemical tests.The isolated bacterial strains were then tested for antibiotic susceptibility by Kirby-Bauer method.The ESBL detection is then carried out by double disc diffusion method.Results:Off the 56 samples cultured,21 strains were identified which were six Escherichia coli(E.coli),six Klebsiella,four Proteus,four Pseudomonas aeruginosa(P.aeruginosa)and only one Acinetobacter.Eight out of 21(38.1%)strains including three of E.coli,three of Klebsiella and two of P.aeruginosa,were found to be resistance to all five antibiotics(piperacillin,amikacin,ampicillin,gentamicin,and ciprofloxacin).Initial screening using four antibiotics(cefotaxime,ceftazidime,aztreonam and ceftriaxone)and the final confirmatory test using ceftazidime/clavulanic acid and ceftazidime alone showed that 19.05%of all strains isolated were ESBL producers.Individually,16.67%E.coli,16.67%Klebsiella pneumoniae,25%P.aeruginosa and 100%Acinetobacter were found to be ESBL producers.Conclusions:Antibiotic resistance by ESBL has become a major risk factor worldwide,therefore routine checkup and accordingly prescription are suggested.
文摘Objective:To study chemical constituents of essential oil of the roots of Nardostachys jatamansi found in different regions of Nepal and also to investigate phytochemical as well as antimicrobial activity of the sample with high yield of essential oil.Methods:The essential oils of roots of plant from five different regions were extracted by hydro-distillation and analyzed by gas chromatography-mass spectroscopy for their chemical constituents.The root samples were also subjected to hydro-alcoholic extraction and then fractionated with hexane,chloroform,n-butanol and water so as to perform phytochemical screening and antimicrobial activity.Results:The essential oil yield of sample from Jumla was found to be the highest followed by a sample from Nepalgunj,Surkhet and Kathmandu whereas that of sample from Dharan was found to be the lowest.Gas chromatography-mass spectrometer analysis of essential oil of five samples showed that“2-beta pinene”appeared dominated in three samples,namely,6VJ Nepalgunj,9VJA Jumla and 10VJ Surkhet.Similarly“alkohol aus neoclovenoxid”in 8VJ Dharan and“methoxy phenyloxime”in 13VJA Kathmandu was found to be present in the highest amount.Phytochemical screening of different fractions of sample 9VJA Jumla showed the presence of alkaloids,terpenoids,glycosides,proteins and amino acids,and carbohydrates etc.Antimicrobial susceptibility test of same fractions showed the n-butanol fraction potent against all pathogens and most affected one was Escherichia coli.Conclusions:Our study suggests that the essential oil of Nardostachys jatamansi found in Nepal contains more than 80 compounds with their quality and quantity differing from place to place.
