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Application of 2-D and 3-D Geo-electrical Resistivity Tomography and Geotechnical Soil Evaluation for Engineering Site Investigation:A Case Study of Okerenkoko Primary School,Warri-Southwest,Delta State,Nigeria
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作者 U.Stanley Eze M.Edirin Okiotor +3 位作者 J.E.Ighodalo B.Jennifer Owonaro A.Saleh Saleh A.Sikiru Jamiu 《Advances in Geological and Geotechnical Engineering Research》 2023年第2期1-23,共23页
In the design of building structures,joint efforts must be decided to resolve the depth of competent layers across the intended site to safeguard the durability of civil engineering structures and to avert the disastr... In the design of building structures,joint efforts must be decided to resolve the depth of competent layers across the intended site to safeguard the durability of civil engineering structures and to avert the disastrous consequences of structural failure and collapse.In this study,an integrated methodology that employed DC resistivity tomography involving 2-D and 3-D techniques and geotechnical-soil analysis was used to evaluate subsoil conditions for engineering site investigation at Okerenkoko primary school,in the Warri-southwest area of Delta State,to adduce the phenomena responsible for the visible cracks/structural failure observed in the buildings.The results obtained brought to light the geological structure beneath the subsurface,which consists of four geoelectric layers identified as topsoil,dry/lithified upper sandy layer,wet sand(water-saturated)and peat/clay/sandy clayey soil(highly water-saturated).The deeply-seated peat/clay materials(ρ≤20Ωm)were delineated in the study area to the depths of 17.1 m and 19.8 m from 2-D and 3-D tomography respectively.3-D images presented as horizontal depth slices revealed the dominance of very low resistivity materials i.e.peat/clay/sandy clay within the fourth,fifth and sixth layers at depths ranging from 8.68-12.5 m,12.5-16.9 m and 16.9-21.9 m respectively.The dominance of mechanically unstable peat/clay/sandy clay layers beneath the subsurface,which are highly mobile in response to volumetric changes,is responsible for the noticeable cracks/failure detected on structures within the study site.These observations were validated by a geotechnical test of soil samples in the study area.Atterberg’s limits of the samples revealed plasticity indices of zero.Thus,the soil samples within the depth analyzed were representatives of sandy soil that does not possess any plasticity.The methods justifiably provided relevant information on the subsurface geology beneath the study site and should be appropriated as major tools for engineering site assessment/geotechnical projects. 展开更多
关键词 2D and 3D resistivity tomography Engineering site/structure atterberg limits Orthogonal lines Radar sounding
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Performance Analysis of Cross⁃Site Scripting Based on Natural Language Processing
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作者 Mengda Xu Luqun Li 《Journal of Harbin Institute of Technology(New Series)》 CAS 2022年第4期19-25,共7页
With the acceleration of network communication in the 5G era,the volume of data communication in cyberspace has increased unprecedentedly.The speed of data transmission will accelerate.Subsequently,the security of net... With the acceleration of network communication in the 5G era,the volume of data communication in cyberspace has increased unprecedentedly.The speed of data transmission will accelerate.Subsequently,the security of network communication data becomes more and more serious.Among them,malicious cross⁃site scripting leading to the leakage of user information is very serious.This article uses URL attribute analysis method and YARA rule to process data for cross⁃site scripting based on the long short⁃term memory(LSTM)characteristics of LSTM model.The results show that the LSTM classification model adopted in this paper has higher recall rate and F1⁃score than other machine learning methods,which proves that the method adopted in this paper is feasible. 展开更多
关键词 cross⁃site scripting network communication web security natural language processing
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Analysis of the Variability of Canopy Resistance over a Desert Steppe Site in Inner Mongolia, China 被引量:3
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作者 ZHANG Guo ZHOU Guangsheng +1 位作者 CHEN Fei WANG Yu 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第3期681-692,共12页
ABSTRACT Canopy resistance substantially affects the partitioning of available energy over vegetated surfaces. This study analyzed the variability of canopy resistance and associated driving environmental factors ove... ABSTRACT Canopy resistance substantially affects the partitioning of available energy over vegetated surfaces. This study analyzed the variability of canopy resistance and associated driving environmental factors over a desert steppe site in Inner Mongolia, China, through the use of eddy-flux and meteorological data collected from 2008 to 2010. Distinct seasonal and interannual variabilities in canopy resistance were identified within those three years, and these variabilities were controlled primarily by precipitation. Strong interannual variability was found in vapor pressure deficit (VPD), similar to that of air temperature. Based on the principal component regression method, the analysis of the relative contribution of five major environmental factors [soil-water content (SWC), leaf-area index (LAI), photosynthetically active radiation (Kp), VPD, and air temperature] to canopy resistance showed that the canopy-resistance variation was most responsive to SWC (with 〉 35% contribution), followed by LAI, especially for water-stressed soil conditions (〉 20% influence), and VPD (consistently with an influence of approximately 20%). Canopy-resistance variations did not respond to Kp due to the small interannual variability in Kp during the three years. These analyses were used to develop a new exponential function of water stress for the widely used Jarvis scheme, which substantially improved the calculation of canopy resistance and latent heat fluxes, especially for moist and wet soils, and effectively reduced the high bias in evaporation estimated by the original Jarvis scheme. This study highlighted the important control of canopy resistance on plant evaporation and growth for the investigated desert steppe site with a relatively low LA1. 展开更多
关键词 VaRIaBILITY canopy resistance desert steppe site principal component regression
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Occurrence of Highly Resistant Microorganisms in Ruai Wastewater Treatment Plant and Dandora Dumpsite in Nairobi County, Kenya 被引量:1
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作者 Edinah Song’oro Andrew Nyerere +1 位作者 Gabriel Magoma Revathi Gunturu 《Advances in Microbiology》 2019年第5期479-494,共16页
Wastewater treatment plants and solid dump sites act as potential reservoirs of highly resistant bacterial strains. This study presents information on the patterns of antimicrobial resistance among pathogenic bacteria... Wastewater treatment plants and solid dump sites act as potential reservoirs of highly resistant bacterial strains. This study presents information on the patterns of antimicrobial resistance among pathogenic bacteria in the sewage treatment plants and solid dump site in Nairobi County, Kenya. We employed standard microbiological methods to isolate and identify bacteria from these selected sites. Members of Escherichia, Klebsiella, Serratia, Shigella, Pseudomonas, Citrobacter spp, Enterobacter, Salmonella, Staphylococcus, Bacillus, Yersinia, Vibro cholera, Providencia, Morganella and Proteus spp were isolated. Escherichia and Klebsiella recorded the highest occurrence at 13.9% and 10.3% in wastewater. Shigella, Serratia Citrobacterfreundii, Pseudomonas, Staphylococcus, Escherichia and Klebsiella recorded the highest level of occurrence at 15.1%, 14.1%, 12%, 11%, 10.4%, 10.3%, and 8.3% in dumpsite respectively. Drug sensitivity using the Disc diffusion method showed that Ampicillin, Ceftazidime, Cefotaxime, Amoxicillin, and Cefepime had the highest levels of inactivity at (68.5%, 89.5%), (64.2%, 87%), (54.5%, 80.2%), (52%, 74%) and (49.1%, 72.4%) respectively while Levofloxacin and Gentamicin showed the smallest level of antibiotic resistance at (4.8%, 4.7%) and (4.2%, 2.6%) in both sites. Members of Escherichia, Klebsiella, Proteus vulgaris, Salmonella, Pseudomonas, Shigella and Serratia showed the highest level of ESBLs production at 28.9%, 18.4%, 15.8%, 10.5%, 7.9%, 7.9%, 7.9% and 7.9% in the wastewater whereas Shigella, Escherichia, Serratia, Pseudomonas, Klebsiella, and Proteus vulgaris showed the highest level ESBLs production at 45.5%, 10.9%, 9.1%, 9.1%, 7.3% and 7.3% from the dump site. All the antibiotics tested except for Gentamicin, Chloramphenicol and Ciprofloxacin differed significantly in terms of resistance levels (p < 0.05). The study concluded that, wastewater treatment plant and dump sites bear heavy burdens of potentially virulent resistant bacterial strains which may constitute major public health hazards to scavengers and those living near these sites. There is need therefore to educate people on the use of appropriate protective materials and the settlement patterns of individuals and communities near these sites. 展开更多
关键词 aNTIBIOTICS resistance Wastewater and Solid DUMP site
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Non-target-site and target-site resistance to AHAS inhibitors in American sloughgrass(Beckmannia syzigachne) 被引量:1
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作者 WANG Jing-jing LI Xiang-ju +4 位作者 LI Dan HAN Yu-jiao LI Zheng YU Hui-lin CUI Hai-lan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第12期2714-2723,共10页
American sloughgrass(Beckmannia syzigachne(Steud.) Fernald) is one of the most competitive and malignant weeds in rice-wheat rotation fields in China. American sloughgrass populations in the Jiangsu Province of China ... American sloughgrass(Beckmannia syzigachne(Steud.) Fernald) is one of the most competitive and malignant weeds in rice-wheat rotation fields in China. American sloughgrass populations in the Jiangsu Province of China became less sensitive to acetohydroxyacid synthase(AHAS) inhibitors after repeated application for many years in these areas. Two suspected resistant American sloughgrass populations(R1 and R2) collected in the field were detected the resistance to inhibitors of AHAS in whole-plant dose-response assays, compared to the susceptible(S) population. These assays indicated that R1 showed low resistance to mesosulfuron-methyl(3.32-fold), imazapic(2.84-fold) and pyroxsulam(1.55-fold), moderate resistance to flazasulfuron(4.67-fold) and pyribenzoxim(7.41-fold), and high resistance to flucarbazone(11.73-fold). However, using a combination of the cytochrome P450 inhibitor, malathion, with mesosulfuron-methyl resulted in a reduction in R1 resistance relative to mesosulfuron-methyl alone. Furthermore, R2 was highly resistant to flazasulfuron(34.90-fold), imazapic(11.30-fold), flucarbazone(49.20-fold), pyribenzoxim(12.94-fold), moderately resistant to mesosulfuron-methyl(9.77-fold) and pyroxsulam(6.26-fold), and malathion had no effect on R2 resistance to mesosulfuron-methyl. The fulllength of AHAS genes was sequenced and the AHAS enzymes were assayed in vitro in order to clarify the mechanism of resistance to AHAS inhibitors in R1 and R2 populations. The results demonstrated that R2 had a Pro-197-Ser mutation in the AHAS gene, and the sensitivity of R2 to the five AHAS inhibitors was decreased, which may result in R2 resistance to AHAS inhibitors. There was no mutation in the AHAS gene of R1, and there were no significant differences in enzyme sensitivity between susceptible(S) and resistant(R1) populations. An enhanced metabolism may be the main mechanism of R1 resistance to AHAS inhibitors. 展开更多
关键词 american sloughgrass CROSS-resistance gene mutation non-target-site resistance
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Nondestructive testing and assessment of consolidation effects of earthen sites
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作者 Xudong Wang Qinglin Guo +2 位作者 Shanlong Yang Dexuan Zhang Yanwu Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2016年第5期726-733,共8页
Earthen sites are widely distributed throughout China, and most of them belong to archaeological sites with significant values, which not only directly witness the origin, formation and development of Chinese civiliza... Earthen sites are widely distributed throughout China, and most of them belong to archaeological sites with significant values, which not only directly witness the origin, formation and development of Chinese civilization, but also possess important values for conservation and exhibition. Many researches and practices on their conservation and consolidation have been carried out; however, the consolidation effect is mainly judged by visual observation and expert evaluation. Scientific assessment of conservation and consolidation effects is a challenging issue. Many instruments in other fields cannot be directly applied to the conservation of cultural relics due to their peculiarity. In order to assess the effects of field conservation experiments, this paper tries to understand the consolidation effects at Liangzhu site using nondestructive or micro-damage methods, including thermo-physical parameters testing, infrared thermal imaging, high-density microelectrode resistivity testing, portable microscope observation, and hydrophilic and hydrophobic testing, and thereby explores the practicable methods for evaluating the properties of consolidation materials for earthen sites treatment. 展开更多
关键词 Earthen sites Nondestructive methods Infrared thermal imaging High-density microelectrode resistivity Portable microscope Hydrophilic and hydrophobic testing
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Cloning and Sequence Analysis of Disease Resistance Gene Analogues from Three Wild Rice Species in Yunnan 被引量:1
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作者 LIUJ-i-mei YANGMing-zhi 《Agricultural Sciences in China》 CAS CSCD 2003年第3期265-272,共8页
Two sets of degenerate oligonucleotide primers were designed according to amino acid conserved regions of reported plant disease resistance genes which encode proteins that contain nucleotide-binding site and leucine-... Two sets of degenerate oligonucleotide primers were designed according to amino acid conserved regions of reported plant disease resistance genes which encode proteins that contain nucleotide-binding site and leucine-rich repeats(NBS-LRR), and the plant disease resistance genes which encode serine/threonine protein kinase(STK). By polymerase chain reaction(PCR), disease resistance gene analogues have been amplified from three wild rice species in Yunnan Province, China. The DIN A fragments from amplification have been cloned into the pGEM-T vector respectively. Sequencing of the DNA fragments indicated that 7 classes, 2 classes and 6 classes NBS-LRR disease resistance gene analogues from Oryza rufipogon Griff. , Oryza officinalis Wall. , and Oryza meyeriana Baill. were obtained respectively. The two representative fragments of TO12 from Oryza officinalis Wall, and TR19 from Oryza rufipogon Griff, belong to the same class and homology of their sequences are 100%. The result shows that the sequences of the same class disease resistance gene analogues have no difference among different species of wild rice. 5 classes STK disease resistance gene analogues were also obtained among which 4 classes from Oryza rufipogon Griff. , 1 class from Oryza officinalis Wall. By comparison analysis of amino acid sequences. we found that the obtained disease resistance gene analogues have very low identity(low to 25%) with the reported disease resistance gene L6, N, Bs2, Prf, Pto, Lr10 and Xa21 etc. The finding suggests that the obtained disease resistance gene analogues are analogues of putative disease resistance genes that have not been isolated so far. 展开更多
关键词 Wild rice Disease-resistance gene Nucleotide-binding site ( NBS) Leucine-rich repeat (LRR) Serine/threonine protein kinase(STK) aNaLOGUES
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Development and Validation of a Laboratory Aging Method for the Accelerated Simulation of Reclaimed Asphalt 被引量:4
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作者 MOLLENHAUER K PIERARD N +2 位作者 TUSAR M MOUILLET V GABET T 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第4期631-636,共6页
The paper presented first results elaborated during the European Research Project Re-road which aims at the development of techniques for increasing the recycling rates of reclaimed asphalt. During service life surfac... The paper presented first results elaborated during the European Research Project Re-road which aims at the development of techniques for increasing the recycling rates of reclaimed asphalt. During service life surface asphalt courses are subjected to aging due to oxidation effects which causes the hardening of the binder and thereby a change in the chemical, physical and mechanical properties of the material. Surface courses often contain highly modified binders as well as special additives for improving the performance characteristics. As these layers inhibit the shortest service lives compared to other road construction layers every year high amounts of reclaimed surface asphalt are available for recycling. The question is raised how the reclaimed asphalt consisting of high quality and costly material components can be recycled for optimal added value. To analyze the asphalt mix service life performance and its recyclability during mix design a laboratory method was developed to simulate the real in-situ aging. First the effects of site aging on the binder and asphalt characteristics were presented. Three laboratory aging methods were discussed which aimed the accelerated aging which meets similar property changes as site aging. At last the effects of two different laboratory aging methods on the same SMA mixture were compared. 展开更多
关键词 asphalt recycling laboratory aging site aging long-term aging validation tests chemical characteristics cracking resistance
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Cloning and Characterization of Full Length cDNA of a CC-NBS-LRR Resistance Gene in Sweetpotato 被引量:2
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作者 CHEN Guan-shui ZHOU Yi-fei +1 位作者 HOU Li-li PAN Da-ren 《Agricultural Sciences in China》 CAS CSCD 2009年第5期538-545,共8页
Conserved domain such as nucleotide binding site (NBS) was found in several cloned plant disease resistance genes. Based on the NBS domain, resistance gene analogues (RGAs) have been isolated. A full-length cDNA, ... Conserved domain such as nucleotide binding site (NBS) was found in several cloned plant disease resistance genes. Based on the NBS domain, resistance gene analogues (RGAs) have been isolated. A full-length cDNA, SPR1 was obtained by rapid amplification of cDNA ends (RACE) method. Sequence analysis indicated that the length of SPR1 was 3 066 bp, including a complete open reading frame of 2 667 bp encoding SPR1 protein of 888 amino acids. Compared with known NBS-LRR genes, it presented relatively high amino acid sequence identity. The polypeptide has a typical structure of nonT1R-NBS-LRR genes, with NB-ARC, CC, and LRR domains. The SPR1-related sequences belonged to multicopy gene family in sweetpotato genome according to the result of Southern blotting. Semi-quantitative RT-PCR analysis showed SPR1 expressed in all tested tissues. The cloning of putative resistance gene from sweetpotato provides a basis for studying the structure and function of sweetpotato disease-resistance relating genes and disease resistant genetic breeding in sweetpotato. The gene has been submitted to the GenBank database, and the accession number is EF428453. 展开更多
关键词 SWEETPOTaTO NBS (nucleotide binding site LRR (leucine-rich repeat) R gene resistance gene)
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Antimicrobial approach of abdominal post-surgical infections
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作者 Marco Fiore Antonio Corrente +6 位作者 Sveva Di Franco Aniello Alfieri Maria Caterina Pace Francesca Martora Stephen Petrou Claudio Mauriello Sebastiano Leone 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第12期2674-2692,共19页
Abdominal surgical site infections(SSIs)are infections that occur after abdominal surgery.They can be superficial,involving the skin tissue only,or more profound,involving deeper skin tissues including organs and impl... Abdominal surgical site infections(SSIs)are infections that occur after abdominal surgery.They can be superficial,involving the skin tissue only,or more profound,involving deeper skin tissues including organs and implanted materials.Currently,SSIs are large global health problem with an incidence that varies significantly depending on the United Nations’Human Development Index.The purpose of this review is to provide a practical update on the latest available literature on SSIs,focusing on causative pathogens and treatment with an overview of the ongoing studies of new therapeutic strategies. 展开更多
关键词 Surgical site infections Multidrug resistance Carbapenem-resistant Enterobacterales Carbapenem-resistant Klebsiella abdominal post-operative complications Post-surgical infections
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Development and mapping of SSR markers linked to resistance-gene homologue clusters in common bean
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作者 Luz Nayibe Garzon Matthew Wohlgemuth Blair 《The Crop Journal》 SCIE CAS 2014年第4期183-194,共12页
Common bean is an important but often a disease-susceptible legume crop of temperate,subtropical and tropical regions worldwide. The crop is affected by bacterial, fungal and viral pathogens. The strategy of resistanc... Common bean is an important but often a disease-susceptible legume crop of temperate,subtropical and tropical regions worldwide. The crop is affected by bacterial, fungal and viral pathogens. The strategy of resistance-gene homologue(RGH) cloning has proven to be an efficient tool for identifying markers and R(resistance) genes associated with resistances to diseases. Microsatellite or SSR markers can be identified by physical association with RGH clones on large-insert DNA clones such as bacterial artificial chromosomes(BACs). Our objectives in this work were to identify RGH-SSR in a BAC library from the Andean genotype G19833 and to test and map any polymorphic markers to identify associations with known positions of disease resistance genes. We developed a set of specific probes designed for clades of common bean RGH genes and then identified positive BAC clones and developed microsatellites from BACs having SSR loci in their end sequences. A total of 629 new RGH-SSRs were identified and named BMr(bean microsatellite RGH-associated markers). A subset of these markers was screened for detecting polymorphism in the genetic mapping population DOR364 × G19833. A genetic map was constructed with a total of 264 markers,among which were 80 RGH loci anchored to single-copy RFLP and SSR markers. Clusters of RGH-SSRs were observed on most of the linkage groups of common bean and in positions associated with R-genes and QTL. The use of these new markers to select for disease resistance is discussed. 展开更多
关键词 Bacterial artificial chromosome(BaC) clone end sequences(BES) Simple sequence repeats(SSRs) Plant disease resistance(R) genes Nucleotide binding site targeted sequencing resistance GENE analogs
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The EPSPS Pro106Ser substitution solely accounts for glyphosate resistance in a goosegrass(Eleusine indica) population from Tennessee, United States 被引量:1
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作者 Janel L Huffman Chance W Riggins +1 位作者 Lawrence E Steckel Patrick J Tranel 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第6期1304-1312,共9页
Previous studies have documented the occurrence of glyphosate-resistant (GR) goosegrass (Eleusine indica (L.) Gaertn.) and, in at least some cases, resistance is due to an altered target site. Research was perfo... Previous studies have documented the occurrence of glyphosate-resistant (GR) goosegrass (Eleusine indica (L.) Gaertn.) and, in at least some cases, resistance is due to an altered target site. Research was performed to determine if an altered target site was responsible for GR in a Tennessee, United States goosegrass population (TennGR). DNA sequencing revealed a mutation in TennGR plants conferring the Prol06Ser 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) substitution previously identified in other GR populations. F2 populations were derived from TennGR plants crossed with plants from a glyphosate-susceptible population (TennGS) and analyzed for their response to glyphosate and genotyped at the EPSPS locus. Plants from the F2 populations segregated 1:2:1 sensitive:intermediate:resistant in response to a selec- tive dose of glyphosate, and these responses co-segregated with the EPSPS genotypes (PP106, PS106, and SS106). To separately investigate the effect of the Prol06Ser substitution on GR, glyphosate dose-response curves and 50% effective dose (EDso) values were compared among the three genotypes and the two parental populations. The SS106 genotype was 3.4-fold resistant relative to the PP106 genotype, identical to the resistance level obtained when comparing the resistant and susceptible parental populations. We conclude that the mutation conferring a Prol06Ser EPSPS mutation is solely responsible for GR in the TennGR goosegrass population. 展开更多
关键词 herbicide resistance monogenic trait GLYPHOSaTE PCR amplification of specific alleles (Pasa EPSPS target-site mutation
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基于地球物理方法的典型DNAPLs污染场地精细化调查
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作者 尹芝华 王水 +2 位作者 冯亚松 吕良华 王海鑫 《环境监测管理与技术》 CSCD 北大核心 2024年第2期44-48,52,共6页
采用高密度电阻率(ERT)和探地雷达(GPR)两种地球物理方法,结合膜界面探测(MIP)和钻孔采样分析手段,综合研究某典型有机污染场地地下水中DNAPLs污染分布情况。结果表明,ERT法和GPR法圈定的场地污染范围基本吻合,DNAPLs污染物主要分布在... 采用高密度电阻率(ERT)和探地雷达(GPR)两种地球物理方法,结合膜界面探测(MIP)和钻孔采样分析手段,综合研究某典型有机污染场地地下水中DNAPLs污染分布情况。结果表明,ERT法和GPR法圈定的场地污染范围基本吻合,DNAPLs污染物主要分布在研究区东北和西南区域,污染深度分别达到4 m和9 m,视电阻率为0.3Ω·m~5Ω·m,呈带状低阻分布,MIP和钻孔采样分析结果也验证了地球物理方法的准确性。 展开更多
关键词 重质非水相液体 高密度电阻率法 探地雷达法 污染场地调查
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The Increased Frequency of Carbapenem Resistant Non Fermenting Gram Negative Pathogens as Causes of Health Care Associated Infections in Adult Cancer Patients
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作者 Hadir A. El-Mahallawy Rasha M. Abdel Hamid +2 位作者 Safaa Shawky Hassan Samah Radwan Magdy Saber 《Journal of Cancer Therapy》 2015年第10期881-888,共8页
Background and Aim: Multi drug resistant Non fermenting gram negative bacilli (NFGNB) have emerged as a major cause of health-care associated infections especially in immunocompromised hosts. The aim of the study was ... Background and Aim: Multi drug resistant Non fermenting gram negative bacilli (NFGNB) have emerged as a major cause of health-care associated infections especially in immunocompromised hosts. The aim of the study was to investigate the prevalence of NFGNB as a cause of health-care associated infections (HAI) in cancer patients and determine their resistance pattern. Patients and Methods: During the study period, 158 NFGNB isolates were collected. Microscan Walk Away 9 was used for identification and testing for the metallo-β-lactamases (MBLs) was done by Imipenem-EDTA combined disk synergy test (CDST-IPM). Results: NFGNB represented 29.0% of infections caused by gram negative organisms. Carbapenem resistance, the multi-drug resistant (MDR) phenotype, and MBL production were documented in 70%, 63%, and 59% of NFGNB isolates, respectively. MDR-NFGNB rates were significantly higher among hospitalized patients, medical department and those with longer duration of hospital stay (p = 0.034, 0.026, 0.019;respectively) than non MDR-NFGNB. Conclusion: A high level of carbapenem and multi-drug resistance were detected among the non-fermenter pathogens isolated from hospitalized cases and were more frequently encountered in high risk adult cancer patients requiring longer duration of hospitalization. The MDR-NFGNB are constituting important causes of health-care associated infections in cancer patients. 展开更多
关键词 Multi Drug RESISTaNT ORGaNISMS (MDRO) Non-Fermenting Gram Negative BaCILLI (NF-GNB) Metallo-β-Lactamases (MBL) Surgical site INFECTIONS (SSI)
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Overview of the seismic input at dam sites in China
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作者 Houqun Chen 《Earthquake Science》 2022年第5期410-425,共16页
The current Chinese national standard,the Standard for Seismic Design of Hydraulic Structures(GB51247),released in 2018,is strictly based on China’s national conditions and dam engineering features.A comprehensive an... The current Chinese national standard,the Standard for Seismic Design of Hydraulic Structures(GB51247),released in 2018,is strictly based on China’s national conditions and dam engineering features.A comprehensive and systematic overview of the basis of the seismic fortification requirements,the framework of the fortification criteria,and the mechanisms of seismic input related to the seismic design of dams are presented herein.We first analyzed and clarified several conceptual aspects in traditional seismic design of dams.Then,for the seismic input at the dam site described in the first national standard for hydraulic structures,we expounded innovative concepts,ideas,and methods to make relevant provisions more realistic and practical and discussed whether reservoir earthquakes must be included in the seismic fortification framework of dams.This study seeks to incorporate seismic input at the dam site into traditional seismic design practice to promote its improvement from the quasi-static method to the dynamic method and from the closed vibration system to an open wave propagation system,to ensure that the seismic design of dams becomes more reasonable,reliable,scientific,and economic. 展开更多
关键词 seismic resistance of dams seismic input at the dam site dynamic dam-foundation interaction closed vibration system open wave propagation system
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Application of high-density resistivity method in archaeological investigation of Sumicheng ancient city site
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作者 XIN Zhonghua HAN Jiangtao +2 位作者 WANG Zhigang LIU Lijia LI Zhuoyang 《Global Geology》 2021年第1期58-63,共6页
The authors employ the high-density resistivity method during an archaeological investigation of Sumicheng site,an ancient city of the Tang Dynasty,to find evidence of human activities and locate a favorable target fo... The authors employ the high-density resistivity method during an archaeological investigation of Sumicheng site,an ancient city of the Tang Dynasty,to find evidence of human activities and locate a favorable target for archaeological excavation in the southern part of the outer city.There are two obvious high-resistivity structures,the south wall of the inner city and an ancient building near the south gate along the outer city wall,of which the resistivities are indicative of rammed soil foundations.The south wall of the inner city is continuous but is cut off abruptly to the east,which we suggest it is due to either wall damage or destruction.The resistivity signature of the target area is verified by archaeological excavation,proving the feasibility and effectiveness of implementing the high-density resistivity method for archaeological exploration. 展开更多
关键词 Sumicheng ancient city site high-density resistivity method archaeological exploration electrical resistivity structure
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Language-Segmented Study Based on TripAdvisor Reviews Related to Memorable Tourist Experiences
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作者 Fernando Toro Sánchez 《Journal of Tourism and Hospitality Management》 2021年第4期204-220,共17页
The Memorable Tourist Experience(MTE)is a scientific concept within the studies on tourism that is developed based on several related constructions:Perceived Confidence,Sincerity,Authenticity,and Satisfaction.This wor... The Memorable Tourist Experience(MTE)is a scientific concept within the studies on tourism that is developed based on several related constructions:Perceived Confidence,Sincerity,Authenticity,and Satisfaction.This work takes this model established by the work of Dr.Babak Taheri in 2018 on Monuments World Heritage of UNESCO,adopting an alternative data collection method to the face-to-face survey.Therefore,this work takes as a source of data the reviews collected in the recommendation platform TripAdvisor,working the same constructions of the MTE,with the collection of similar terms and the relationships between them.In order to highlight the terms,a first step is established with the use of Natural Language Processing(NLP),followed by the use of Machine Learning(ML)techniques to generate the relationships between the constructors defined in the models.The study makes a comparison using the method,in immaterial nature such as a flamenco show in the city of Seville;Flamenco has been declared by UNESCO an intangible World Heritage Site since 2010.The results of the study go in two directions:on the one hand to find similarities in the study of the specific MTE of both monuments with the hypotheses worked in the original model of Taheri.In addition to highlighting possible distinctive elements of each case and,and furthermore within the value contribution of the visit when it is led by an official tour guide,on the other hand,give presence to the model of obtaining data by reviews as a complementary data source of any tourist study.The data collection and analysis from both NLP and ML techniques permit the scientific study and the tourist operators to develop better value propositions to users and understanding of heterogeneous behaviors in the tourism industry.The study of reviews within the MTE allows identifying the stimulus that leads the user to choose an activity and hire it.These studies are extendable to other industries and business models,given the importance that references acquire within the consumer willing to buy.For the scientific community,the use of ML is a solid way to initiate studies on behavioral models,supplement them,and accept or reject hypotheses.When the source of the data is taken from free expressions,such as reviews,the appearance of bias in the behavior is attenuated. 展开更多
关键词 Memorable Tourist Experience(MTE) Tripadvisor World Heritage site Machine Learning(ML) Natural language Processing(NLP)
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SHEA/IDSA/APIC实践建议:预防医院感染策略纲要(2022年更新版)
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作者 肖园园 谭彩霞(译) +3 位作者 吴安华(审校) Yokoe DA Advani SD Anderson DJ 《中国感染控制杂志》 CAS CSCD 北大核心 2024年第5期652-660,共9页
美国医疗保健流行病学学会/美国感染病协会/感染控制和流行病学专业人员协会(SHEA/IDSA/APIC)2022年更新了“急诊医院医疗保健相关感染的预防策略纲要”,内容包括“导尿管相关尿路感染(CAUTI)的预防策略”“中央导管相关血流感染(CLABSI... 美国医疗保健流行病学学会/美国感染病协会/感染控制和流行病学专业人员协会(SHEA/IDSA/APIC)2022年更新了“急诊医院医疗保健相关感染的预防策略纲要”,内容包括“导尿管相关尿路感染(CAUTI)的预防策略”“中央导管相关血流感染(CLABSI)的预防策略”“艰难梭菌感染(CDI)的预防策略”“预防耐甲氧西林金黄色葡萄球菌(MRSA)传播和感染的策略”“手术部位感染(SSI)的预防策略”“呼吸机相关肺炎(VAP)和呼吸机相关事件(VAE)的预防策略”“预防非呼吸机医院获得性肺炎(NV-HAP)的策略”“通过手卫生预防医疗保健相关感染的策略”“实施预防医疗保健相关感染的策略”九部分。 展开更多
关键词 医院感染 导尿管相关尿路感染 中央导管相关血流感染 艰难梭菌感染 耐甲氧西林金黄色葡萄球菌 手术部位感染 呼吸机相关肺炎 呼吸机相关事件 非呼吸机医院获得性肺炎 手卫生 医疗保健相关感染 预防策略
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大肠杆菌ATCase抗反馈抑制突变体的构建及其对胞苷积累的影响 被引量:3
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作者 方海田 周运佼 +1 位作者 谢希贤 陈宁 《天津科技大学学报》 CAS 2012年第4期12-16,共5页
为解决胞苷生物合成途径中天冬氨酸氨甲酰转移酶受胞苷三磷酸反馈抑制调节的问题,通过对其碱基序列和蛋白质结构分析,利用基因定点突变的方法构建了大肠杆菌的ATCase突变酶,得到三个突变体:M1(H20L)、M2(K60E)、M3(K94E),并在E.coli DH... 为解决胞苷生物合成途径中天冬氨酸氨甲酰转移酶受胞苷三磷酸反馈抑制调节的问题,通过对其碱基序列和蛋白质结构分析,利用基因定点突变的方法构建了大肠杆菌的ATCase突变酶,得到三个突变体:M1(H20L)、M2(K60E)、M3(K94E),并在E.coli DH5α中对融合蛋白进行了表达.酶活测定表明,M1、M2、M3的ATCase酶相对活性都比野生型M0的高,分别为野生型M0的1.10、1.22和1.37倍,且比活力都有不同程度提高.与含野生型pyrBI基因的M0相比,含突变型基因的M1、M2和M3均对15,mmol/L的CTP具有强的抗反馈抑制作用,且M1、M2和M3的抗CTP反馈抑制作用分别是M0的5.4、6.0和8.5倍.最后将各突变质粒转入到E.coli Cyt10(Δcdd)中进行发酵培养,结果表明,与未含突变基因菌株相比,各含突变基因菌株的胞苷积累量均有不同程度的提高,说明ATCase定点突变使胞苷的合成积累途径得到了不同程度的强化. 展开更多
关键词 大肠杆菌 胞苷 天冬氨酸转氨甲酰酶 定点突变 抗反馈抑制
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安徽省部分地区冬小麦田日本看麦娘Alopecurus japonicus对精鰁唑禾草灵的抗性发生现状及ACCase基因突变研究 被引量:5
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作者 赵宁 王豪 +2 位作者 张乐乐 刘伟堂 王金信 《农药学学报》 CAS CSCD 北大核心 2019年第1期35-42,共8页
日本看麦娘Alopecurus japonicus是中国冬小麦田和油菜田主要恶性禾本科杂草之一。为了明确安徽省部分地区日本看麦娘对精齅唑禾草灵抗性发生情况及可能存在的抗性机制,本研究在安徽省天长市日本看麦娘发生严重区域冬小麦田共采集10个种... 日本看麦娘Alopecurus japonicus是中国冬小麦田和油菜田主要恶性禾本科杂草之一。为了明确安徽省部分地区日本看麦娘对精齅唑禾草灵抗性发生情况及可能存在的抗性机制,本研究在安徽省天长市日本看麦娘发生严重区域冬小麦田共采集10个种群,采用温室盆栽法在整株水平上测定了不同种群对精齅唑禾草灵的抗性水平,扩增并比对了抗性和敏感种群之间靶标酶乙酰辅酶A羧化酶(Acetyl-CoA carboxylase,ACCase)基因部分序列的差异。结果显示,与敏感种群相比, 1 0个抗性种群对精齅唑禾草灵均产生了高水平抗性,抗性指数在30.50~58.55之间。不同抗性种群均发生了ACCase基因突变,其中8个种群发生了第1 781位异亮氨酸(Ile)到亮氨酸(Leu)突变,2个种群发生了第2 027位色氨酸(Trp)到半胱氨酸(Cys)突变。此外,各种群均具有较高的ACCase基因突变频率(≥80%)。研究表明,抗性日本看麦娘在安徽省部分地区发生较为严重,ACCase基因突变是导致不同日本看麦娘种群对精齅唑禾草灵产生抗性的重要原因之一。相对于第2 027位,日本看麦娘ACCase基因更倾向于在第1 781位产生突变以表现靶标抗性。 展开更多
关键词 日本看麦娘 精齅唑禾草灵 乙酰辅酶a羧化酶 靶标抗性 基因突变
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