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Core and variable antimicrobial resistance genes in the gut microbiomes of Chinese and European pigs
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作者 Cui-Hong Tong Zhi-Peng Huo +4 位作者 Lu Diao Dan-Yu Xiao Ruo-Nan Zhao Zhen-Ling Zeng Wen-Guang Xiong 《Zoological Research》 SCIE CSCD 2024年第1期189-200,共12页
Monitoring the prevalence of antimicrobial resistance genes(ARGs)is vital for addressing the global crisis of antibiotic-resistant bacterial infections.Despite its importance,the characterization of ARGs and microbiom... Monitoring the prevalence of antimicrobial resistance genes(ARGs)is vital for addressing the global crisis of antibiotic-resistant bacterial infections.Despite its importance,the characterization of ARGs and microbiome structures,as well as the identification of indicators for routine ARG monitoring in pig farms,are still lacking,particularly concerning variations in antimicrobial exposure in different countries or regions.Here,metagenomics and random forest machine learning were used to elucidate the ARG profiles,microbiome structures,and ARG contamination indicators in pig manure under different antimicrobial pressures between China and Europe.Results showed that Chinese pigs exposed to high-level antimicrobials exhibited higher total and plasmid-mediated ARG abundances compared to those in European pigs(P<0.05).ANT(6)-Ib,APH(3')-IIIa,and tet(40)were identified as shared core ARGs between the two pig populations.Furthermore,the core ARGs identified in pig populations were correlated with those found in human populations within the same geographical regions.Lactobacillus and Prevotella were identified as the dominant genera in the core microbiomes of Chinese and European pigs,respectively.Forty ARG markers and 43 biomarkers were able to differentiate between the Chinese and European pig manure samples with accuracies of 100%and 98.7%,respectively.Indicators for assessing ARG contamination in Chinese and European pigs also achieved high accuracy(r=0.72-0.88).Escherichia flexneri in both Chinese and European pig populations carried between 21 and 37 ARGs.The results of this study emphasize the importance of global collaboration in reducing antimicrobial resistance risk and provide validated indicators for evaluating the risk of ARG contamination in pig farms. 展开更多
关键词 METAGENOMIC Pig manure Antimicrobial pressure Antimicrobial resistance genes MICROBIOME
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Effect of Radial Resistance Gap on the Pressure Drop of a Compact Annular-Radial-Orifice Flow Magnetorheological Valve 被引量:4
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作者 Guoliang Hu Jiawei Zhang +1 位作者 Mingke Liao Ruqi Ding 《Journal of Beijing Institute of Technology》 EI CAS 2018年第4期535-546,共12页
A compact annular-radial-orifice flow magnetorheological(MR)valve was developed to investigate the effects of radial resistance gap on pressure drop.The fluid flow paths of this proposed MR valve consist of a single a... A compact annular-radial-orifice flow magnetorheological(MR)valve was developed to investigate the effects of radial resistance gap on pressure drop.The fluid flow paths of this proposed MR valve consist of a single annular flow channel,a single radial flow channel and an orifice flow channel through structure design.The finite element modelling and simulation analysis of the MR valve was carried out using ANSYS/Emag software to investigate the changes of the magnetic flux density and yield stress along the fluid flow paths under the four different radial resistance gaps.Moreover,the experimental tests were also conducted to evaluate the pressure drop,showing that the proposed MR valve has significantly improved its pressure drop at 0.5 mm width of the radial resistance gap when the annular resistance gap is fixed at 1 mm. 展开更多
关键词 magnetorheological(MR)valve annular-radial-orifice flow pressure drop radial resistance gap finite element analysis
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Finite element analysis of stiffness and static dent resistance of aluminum alloy double-curved panel in viscous pressure forming 被引量:10
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作者 LI Yi WANG Zhong-Jin 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2009年第S02期312-317,共6页
The static dent resistance performance of the aluminum alloy double-curved panel formed using viscous pressure forming (VPF)was studied by finite element analysis,which mainly considers the forming process conditions.... The static dent resistance performance of the aluminum alloy double-curved panel formed using viscous pressure forming (VPF)was studied by finite element analysis,which mainly considers the forming process conditions.The whole simulation consisting of three stages,i.e.,forming,spring-back and static dent resistance,was carried out continuously using the finite element code ANSYS.The influence of blank holder pressure(BHP)and the drawbead on the stiffness and the static dent resistance of the panels formed using VPF was analyzed.The results show that the adequate setting of the drawbead can increase the plastic deformation of the double-curved panel,which is beneficial to the initial stiffness and the static dent resistance.There is an optimum BHP range for the stiffness and the static dent resistance. 展开更多
关键词 aluminum alloy double-curved panel viscous pressure forming panel stiffness static dent resistance finite element analysis
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Pneumatic resistance network analysis and dimension optimization of high pressure electronic pneumatic pressure reducing valve 被引量:2
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作者 徐志鹏 王宣银 《Journal of Central South University》 SCIE EI CAS 2011年第3期666-671,共6页
The structure and working principle of a self-deigned high pressure electronic pneumatic pressure reducing valve (EPPRV) with slide pilot are introduced.The resistance value formulas and the relationship between the r... The structure and working principle of a self-deigned high pressure electronic pneumatic pressure reducing valve (EPPRV) with slide pilot are introduced.The resistance value formulas and the relationship between the resistance and pressure of three typical pneumatic resistances are obtained.Then,the method of static characteristics analysis only considering pneumatic resistances is proposed,the resistance network from gas supply to load is built up,and the mathematical model is derived from the flow rate formulas and flow conservation equations,with the compressibility of high pressure gas and temperature drop during the expansion considered in the model.Finally,the pilot spool displacement of 1.5 mm at an output pressure of 15MPa and the enlarging operating stroke of the pilot spool are taken as optimization targets,and the optimization is carried out based on genetic algorithm and the model mentioned above.The results show that the static characteristics of the EPPRV are significantly improved.The idea of static characteristics analysis and optimization based on pneumatic resistance network is valuable for the design of pneumatic components or system. 展开更多
关键词 high pressure pressure reducing valve pneumatic resistance dimension optimization genetic algorithm
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Improving the Corrosion Resistance of ZEK100 Magnesium Alloy by Combining High-Pressure Torsion Technology with Hydroxyapatite Coating 被引量:5
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作者 Qite Li Wenbo Ye +1 位作者 Hong Gao Lilan Gao 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期170-170,共1页
Recently,magnesium and its alloys have attracted more and more attention as promising implant materials due to their excellent properties such as good biocompatibility,biodegradation,non-toxicity and comparable mechan... Recently,magnesium and its alloys have attracted more and more attention as promising implant materials due to their excellent properties such as good biocompatibility,biodegradation,non-toxicity and comparable mechanical properties with natural bone.They can be gradually degraded and absorbed so as to avoid the second surgery for implants removal after the tissues are healed completely.In addition,they are also able to prevent the stress shielding effect in human body environment because of the density,elastic modulus and yield strength of magnesium closer to the bone.Unfortunately,the high corrosion rate which causes early mechanical failure of the implants in physiological environment limits the widespread use of magnesium alloys for clinical application in biology.And the high corrosion process usually causes huge hydrogen evolution and alkalinization,resulting in problems against the implants as well as the surrounding tissues.In order to enhance the corrosion resistance of magnesium alloys,in this study,the ZEK100 magnesium alloy was pre-deformed with a highpressure torsion(HPT)process and then fabricated hydroxyapatite(HA)coatings with different contents of Mg(OH)2 nanopowder via hydrothermal method.The specimens were characterized by scanning electron microscope(SEM)and X-ray diffraction(XRD).At the same time,prior and after the HPT procedure,the metallography,microhardness and tensile tests of specimens were characterized.Meanwhile,the corrosion behavior of the specimens was evaluated by electrochemical impedance spectroscopy(EIS)and hydrogen evolution tests.And the interface bonding strength of the HA coating on the magnesium alloy substrate was evaluated by a tape adhesion test/scratch test.Results showed that HPT processing refined the grain size and introduced a great number of twins,resulting in the enhancement of microhardness and Young’s modulus of ZEK100 magnesium alloy,but hardness values at the edge were higher than those at the center due to the uneven shear strain.At the same conditions,the HA coating on HPT-ZEK was denser,thicker than that on ZEK sample and the crystal sizes of HA were smaller on HPT-ZEK.These were attributed to fine,uniform distributed secondary phases and lots of fine grains,twins,grain boundaries in HPT-ZEK substrates which can provide more nucleation sites for the HA crystal.In terms of the amount of Mg(OH)2 nanopowder,Mg(OH)2 nanopowder significantly influenced the microstructure and thickness of the HA coating.And at a 0.3 mg/mL content of Mg(OH)2 nanopowder,there was the densest,thickest HA coating on magnesium alloys,and the crystal size of HA was minimum.Specifically,the HA coating thickness on ZEK-03(0.3 mg/mL Mg(OH)2 nanopowder)was 1.8 times of that on ZEK-00(0 mg/mL Mg(OH)2 nanopowder),while the HA coating thickness on HPT-03 was 2.6 times of that on ZEK-00.And the adhesion strength of HA coating on HPT-03 substrate was better than that on ZEK-03.In addition,HPT technology and surface modification by HA coating simultaneously increased the corrosion resistance of ZEK100 magnesium alloy and the corrosion of HPT-ZEK samples occurred in a more uniform manner,while it was pitting on the surface of ZEK100 magnesium alloy.Therefore,there was the best corrosion resistance on HPT-03 sample,which could promote the application of magnesium alloys in biomedical fields. 展开更多
关键词 high-pressure TORSION surface modification hydroxyapatite(HA) MG(OH)2 corrosion resistance
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Relationship between Plasma Ghrelin Levels and Insulin Resistance and Blood Pressure in Octogenarians
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作者 赵荫涛 邵莉 +2 位作者 滕丽莉 张代富 张华 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第3期307-311,共5页
The association between fasting plasma ghrelin levels and insulin resistance and blood pressure(BP) in octogenarians was investigated in this study.A total of 487 unrelated octogenarians(including 203 men and 284 wome... The association between fasting plasma ghrelin levels and insulin resistance and blood pressure(BP) in octogenarians was investigated in this study.A total of 487 unrelated octogenarians(including 203 men and 284 women) were enrolled in this cross-sectional study at the Healthy Care Center of Shanghai East Hospital,Tongji University,China,from October 2008 to April 2009.Plasma ghrelin was determined by using the enzyme linked immunosorbent assay(ELISA).Insulin sensitivity was assessed using the homeostasis model of assessment-insulin resistance(HOMA-IR).The age of the participants ranged from 80 to 89 years(mean=83.9±4.8 years) with a body mass index(BMI) of 25.3±4.9 kg/m2.Plasma ghrelin level[w1]s were 20.94±5.34 μg/L,being 20.89±5.53 μg/L in men and 21.38±3.73 μg/L in women respectively.Plasma ghrelin was not associated with systolic(P=0.981) or diastolic(P=0.724) BP,waist circumference(P=0.278),fasting insulin(P=0.246),fasting blood glucose(FBG)(P=0.693) and HOMA-IR(P=0.232).In the control cohort,no significant differences in plasma ghrelin were found between genders(P=0.489),and among subjects with hypertension(BP>140/90 mmHg)(P=0.284) and type 2 diabetes(P=0.776).In conclusion,fasting plasma ghrelin levels are not directly correlated with insulin resistance and BP among octogenarians. 展开更多
关键词 GHRELIN insulin resistance blood pressure ELDERLY
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In situ electrical resistance and activation energy of solid C_(60) under high pressure
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作者 杨洁 刘才龙 高春晓 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期516-519,共4页
The in situ electrical resistance and transport activation energies of solid C60 fullerene have been measured under high pressure up to 25 GPa in the temperature range of 300-423 K by using a designed diamond anvil ce... The in situ electrical resistance and transport activation energies of solid C60 fullerene have been measured under high pressure up to 25 GPa in the temperature range of 300-423 K by using a designed diamond anvil cell. In the experiment, four parts of boron-doped diamond films fabricated on one anvil were used as electrical measurement probes and a W-Ta thin film thermocouple which was integrated on the other diamond anvil was used to measure the temperature. The current results indicate that the measured high-pressure resistances are bigger than those reported before at the same pressure and there is no pressure-independent resistance increase before 8 GPa. From the temperature dependence of the resistivity, the C60 behaviors as a semiconductor and the activation energies of the cubic C60 fullerene are 0,49, 0.43, and 0.36 eV at 13, 15, and 19 GPa, respectively. 展开更多
关键词 high pressure electrical resistance activation energy C60 fullerene
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Effects of High Pressure Treatment on Microstructure and Corrosion Resistance of Brass
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作者 Guangying Sun Yu Feng Huan He 《材料科学与工程(中英文版)》 2011年第5期546-549,共4页
关键词 高压处理 微观组织 黄铜 耐蚀性 耐腐蚀性 电化学方法 X射线衍射 微观结构
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Ocular manifestations of central insulin resistance 被引量:2
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作者 Muneeb A.Faiq Trina Sengupta +5 位作者 Madhu Nath Thirumurthy Velpandian Daman Saluja Rima Dada Tanuj Dada Kevin C.Chan 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第5期1139-1146,共8页
Central insulin resistance, the diminished cellular sensitivity to insulin in the brain, has been implicated in diabetes mellitus, Alzheimer’s disease and other neurological disorders. However, whether and how centra... Central insulin resistance, the diminished cellular sensitivity to insulin in the brain, has been implicated in diabetes mellitus, Alzheimer’s disease and other neurological disorders. However, whether and how central insulin resistance plays a role in the eye remains unclear. Here, we performed intracerebroventricular injection of S961, a potent and specific blocker of insulin receptor in adult Wistar rats to test if central insulin resistance leads to pathological changes in ocular structures. 80 mg of S961 was stereotaxically injected into the lateral ventricle of the experimental group twice at 7 days apart, whereas buffer solution was injected to the sham control group. Blood samples, intraocular pressure, trabecular meshwork morphology, ciliary body markers, retinal and optic nerve integrity, and whole genome expression patterns were then evaluated. While neither blood glucose nor serum insulin level was significantly altered in the experimental or control group, we found that injection of S961 but not buffer solution significantly increased intraocular pressure at 14 and 24 days after first injection, along with reduced porosity and aquaporin 4 expression in the trabecular meshwork, and increased tumor necrosis factor α and aquaporin 4 expression in the ciliary body. In the retina, cell density and insulin receptor expression decreased in the retinal ganglion cell layer upon S961 injection. Fundus photography revealed peripapillary atrophy with vascular dysregulation in the experimental group. These retinal changes were accompanied by upregulation of pro-inflammatory and pro-apoptotic genes, downregulation of anti-inflammatory, anti-apoptotic, and neurotrophic genes, as well as dysregulation of genes involved in insulin signaling. Optic nerve histology indicated microglial activation and changes in the expression of glial fibrillary acidic protein, tumor necrosis factor α, and aquaporin 4. Molecular pathway architecture of the retina revealed the three most significant pathways involved being inflammation/cell stress, insulin signaling, and extracellular matrix regulation relevant to neurodegeneration. There was also a multimodal crosstalk between insulin signaling derangement and inflammation-related genes. Taken together, our results indicate that blocking insulin receptor signaling in the central nervous system can lead to trabecular meshwork and ciliary body dysfunction, intraocular pressure elevation, as well as inflammation, glial activation, and apoptosis in the retina and optic nerve. Given that central insulin resistance my lead to neurodegenerative phenotype in the visual system, targeting insulin signaling may hold promise for vision disorders involving the retina and optic nerve. 展开更多
关键词 brain ciliary bodies gene expression inflammation insulin receptor insulin resistance intraocular pressure NEURODEGENERATION optic nerve RETINA retinal ganglion cells trabecular meshwork
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Hemodynamic Profiling Using a Cardiac Index–Systemic Vascular Resistance Plot in Patients with Fontan Circulation
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作者 Yuki Kawasaki Takeshi Sasaki Daisuke Kobayashi 《Congenital Heart Disease》 SCIE 2023年第4期431-445,共15页
Background: Elevated Fontan pressure (FP) alone cannot fully predict clinical outcomes. We hypothesized thathemodynamic profiling using a cardiac index (CI)-systemic vascular resistance (SVR) plot could characterize c... Background: Elevated Fontan pressure (FP) alone cannot fully predict clinical outcomes. We hypothesized thathemodynamic profiling using a cardiac index (CI)-systemic vascular resistance (SVR) plot could characterize clinicalfeatures and predict the prognosis of post-Fontan patients. Methods: We included post-Fontan patients whounderwent cardiac catheterization at age < 10 years. Patients were classified into four categories: A, CI ≥ 3, SVRindex (SVRI) ≥ 20;B, CI < 3, SVRI ≥ 20;C, CI ≥ 3, SVRI < 20;and D, CI < 3, SVRI < 20. The primary outcome wasfreedom from the combined endpoint: new onset of protein-losing enteropathy or plastic bronchitis, heart transplant,and death. Clinical and hemodynamic variables and freedom from the endpoint were compared betweenthe hemodynamic categories and outcome predictors were evaluated. Results: Eighty-three patients wereincluded. Median follow-up was 5.3 years. Category A/B/C/D consisted of 4/15/53/11 patients, respectively. Allthe patients in category A were New York Heart Association I/II and had a significantly lower pulmonary vascularresistance index (PVRI). Patients in category C had lower pulmonary/systemic blood flow. Patients in category Dhad a higher PVRI and had the poorest freedom from the endpoint (44% at 5 years). Elevated FP and category Dwere outcome predictors. Conclusions: CI-SVR plots was a novel adjunctive method for Fontan hemodynamicprofiling. 展开更多
关键词 Cardiac index systemic vascular resistance perfusion pressure hemodynamic category fontan circulation PROGNOSIS
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Effect of N_(2) partial pressure on comprehensive properties of antibacterial TiN/Cu nanocomposite coating
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作者 Hui Liu Yanhui Zhao +10 位作者 Chuanshi Sui Yi Li Muhammad Ali Siddiqui Susu Li Tong Li Shuyuan Zhang Hai Wang Tao Jin Ling Ren Ke Yang Ning Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第1期131-143,共13页
Foreign body reactions to the wear debris and corrosion products from the implants,and bacterial infections are the main factors leading to the implant failures.In order to resolve these problems,the antibacterial TiN... Foreign body reactions to the wear debris and corrosion products from the implants,and bacterial infections are the main factors leading to the implant failures.In order to resolve these problems,the antibacterial TiN/Cu nanocomposite coatings with various N_(2) partial pressures were deposited on 304 stainless steels(SS)using an arc ion plating(AIP)system,named TiN/Cu-x(x=0.5,1.0,1.5 Pa).The results of X-ray diffraction analysis,energy-dispersive X-ray spectroscopy,and scanning electron microscopy showed that the N_(2) partial pressures determined the Cu contents,surface defects,and crystallite sizes of TiN/Cu nanocomposite coatings,which further influenced the comprehensive abilities.And the hardness and wear resistances of TiN/Cu coatings were enhanced with increase of the crystallite sizes.Under the co-actions of surface defects,crystallite sizes,and Cu content,TiN/Cu-1.0 and TiN/Cu-1.5 coatings possessed excellent corrosion resistance.Besides,the biological tests proved that all the TiN/Cu coatings showed no cytotoxicity with strong antibacterial ability.Among them,TiN/Cu-1.5 coating significantly promoted the cell proliferation,which is expected to be a novel antibacterial,corrosion-resistant,and wear-resistant coating on the surfaces of medical implants. 展开更多
关键词 N_(2)partial pressure TiN/Cu coating wear resistance corrosion behavior antibacterial ability CYTOCOMPATIBILITY
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Local resistance characteristics of elbows for supercritical pressure RP-3 flowing in serpentine micro-tubes
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作者 Yanchen Fu Yinlong Liu +3 位作者 Juan Wang Yu Wang Guoqiang Xu Jie Wen 《Propulsion and Power Research》 SCIE 2024年第2期245-256,共12页
Based on the demands of compact heat exchangers and micro cooling channels applied for aviation thermal protection on aero-engines,the elbow localflow resistance charac-teristics for supercritical pressure aviation fu... Based on the demands of compact heat exchangers and micro cooling channels applied for aviation thermal protection on aero-engines,the elbow localflow resistance charac-teristics for supercritical pressure aviation fuel RP-3flowing in adiabatic horizontal serpentine tubes with the inner diameter of 1.8 mm and the massflux of 1179 kg/(m^(2)·s)were experimen-tally studied.The long-short-tube method was used to obtain the elbow pressure drop from the total serpentine tube pressure drop,and the effects of system pressures(P/Pc=1.72-2.58)and geometry parameters including bend numbers(n=5-11),bend diameters(D/d=16.7-27.8),and bend distances(L/d=20-60)on elbow pressure drops and local resistance co-efficients are analyzed on the basis of the thermal physical property variation.The results show that both the increase in the elbow pressure drop and the decrease in the local resistance coef-ficient with temperatures speed up at the near pseudo-critical temperature region of T>0.85Tpc.And the growth of the elbow local pressure drop could be inhibited by the increase of system pressures,while the local resistance coefficient is slightly affected by pressures.The influence of bend diameters on the local resistance coefficient is mild when D/d is larger than 22.2 in the premise of fully developedflow in straight tubes.Furthermore,a piecewise empir-ical correlation considering the bend diameter and physical property ratio is developed to pre-dict the elbow pressure drop of the serpentine tube and optimize the layout of the cooling tube system on aero-engines. 展开更多
关键词 Supercritical pressure Aviation fuel Local resistance coefficient ELBOW Serpentine tube Empirical correlation
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Clinical characteristics, target organ damage and associate risk factors ofresistant hypertension determined by ambulatory blood pressure monitoringin patients aged ≥80 years
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作者 Zhi-Ru LIANG Ling-Gen GAO +3 位作者 Jian CAO Hua CUI Li FAN De-Wei GAO 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2017年第5期308-314,共7页
Objectives To investigate clinical characteristics, target organ damage, and the associated risk factors of the patients aged ≥ 80 yearswith true resistant hypertension (RH). Methods Patients aged ≥ 80 years with ... Objectives To investigate clinical characteristics, target organ damage, and the associated risk factors of the patients aged ≥ 80 yearswith true resistant hypertension (RH). Methods Patients aged ≥ 80 years with hypertension (n = 1163) were included in this study. Theincluded participants attended a structured clinical examination and an evaluation of RH was carried out. The prevalence, clinical characteristicsand target organ damage of patients with RH were assessed. The associated clinical risk factors were analyzed by using logistic regression.Results The prevalence of RH diagnosis by 24-h ambulatory blood pressure monitoring assessment was 21.15%. End-diastolic left ven-tricular internal dimension, left ventricular mass index as well as prevalence of left ventricular hypertrophy were significantly greater in pa-tients with RH than in control group. The common carotid artery intimal media thickness, carotid walls thickness, common carotid arterydiameter and relative wall thickness were significant greater in RH group than in control. A relatively higher level of creatinine, estimatedglomerular filtration rate, microalbuminuria and retinal changes was found in RIt group than in control. A multivariate analysis showed thatpatients with a history of diabetes, higher body mass index (BMI) and lipid profiles were independent risk factors of RH. Conclusions Theprevalence of RH in patients aged ≥ 80 years was within the range of reported rates of the general population. Subjects with RH diagnosisshowed a higher occurrence of target organ damage than patients with well controlled blood pressure. Patients with diabetes, higher BMI andserum lipid profiles were independent risk factors for RH in patients aged ≥ 80 years. 展开更多
关键词 BLOOD pressure ORGAN damage resistANT HYPERTENSION
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The Analysis of the Line Pattern of Nonlinear Winding Filament on FRP Composite Air Vessel Resisting High Pressure
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作者 WANG Zhihui ZHANG Jifa WANG Bingshan School of Mechatronic Engineering,Wuhan University of Technology,Wuhan 430070,China, 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S3期899-902,共4页
The FW process is a prefect method of manufacturing FRP composite air vessel resisting high pressure and aerial press vessel.In this paper FW pattern of FRP composite air vessel resisting high pressure was analyzed in... The FW process is a prefect method of manufacturing FRP composite air vessel resisting high pressure and aerial press vessel.In this paper FW pattern of FRP composite air vessel resisting high pressure was analyzed in a nutshell.The stability of FW patterns on end head is very sensitive to changing of pattern parameter.Consequently,its FW pattern was based on geodesic track.The FW angles and on equators depend on the dimension of end part and the condition of geodesic FW.Generally speaking, the polar holes of rocket engine shell are disproportional.Therefore,the FW angles of the shell column are changeable.The feasi- bility of nongeodesic FW of the shell column was discussed in this paper.Furthermore,it expounded the indispensable condition be- tween the length of shell column and the FW friction coefficient.At the same time,the general mathematic models of the movement control of nongeodesic FW were deduced. 展开更多
关键词 COMPOSITE air VESSEL resisting high pressure FILAMENT WINDING LINE PATTERN
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Nonlinear uniaxial pressure dependence of the resistivity in Sr_(1-x)Ba_xFe_(1.97)Ni_(0.03)As_2
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作者 Hui-Can Mao Dong-Liang Gong +4 位作者 Xiao-Yan Ma Hui-Qian Luo Yi-Feng Yang Lei Shan and Shi-Liang Li 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期511-516,共6页
Nematic order and its fluctuations have been widely found in iron-based superconductors. Above the nematic order transition temperature, the resistivity shows a linear relationship with the uniaxial pressure or strain... Nematic order and its fluctuations have been widely found in iron-based superconductors. Above the nematic order transition temperature, the resistivity shows a linear relationship with the uniaxial pressure or strain along the nematic direction and the normalized slope is thought to be associated with nematic susceptibility. Here we systematically studied the uniaxial pressure dependence of the resistivity in Sr1 _xBaxFel.97Nio.03As2, where nonlinear behaviors are observed near the nematic transition temperature. We show that it can be well explained by the Landau theory for the second-order phase transitions considering that the external field is not zero. The effect of the coupling between the isotropic and nematic channels is shown to be negligible. Moreover, our results suggest that the nature of the magnetic and nematic transitions in Srl xBaxFe2As2 is determined by the strength of the magnetic-elastic coupling. 展开更多
关键词 iron-based superconductors nematic order uniaxial pressure resistIVITY
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DESIGN OF NOVEL HIGH PRESSURE-RESISTANT HYDROTHERMAL FLUID SAMPLE VALVE 被引量:2
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作者 LIU Wei YANG Canjun WU Shijun XIE Yingjun CHEN Ying 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第1期72-76,共5页
Sampling study is an effective exploration method, but the most extreme environments of hydrothermal vents pose considerable engineering challenges for sampling hydrothermal fluids. Moreover, traditional sampler syste... Sampling study is an effective exploration method, but the most extreme environments of hydrothermal vents pose considerable engineering challenges for sampling hydrothermal fluids. Moreover, traditional sampler systems with sample valves have difficulty in maintaining samples in situ pressure. However, decompression changes have effect on microorganisms sensitive to such stresses. To address the technical difficulty of collecting samples from hydrothermal vents, a new bidirectional high pressure-resistant sample valve with balanced poppet was designed. The sample valve utilizes a soft high performance plastic "PEEK" as poppet. The poppet with inapposite dimension is prone to occur to plastic deformation or rupture for high working pressure in experiments. To address this issue, based on the fmite element model, simulated results on stress distribution of the poppet with different structure parameters and preload spring force were obtained. The static axial deformations on top of the poppet were experimented. The simulated results agree with the experimental results. The new sample valve seals well and it can withstand high working pressure. 展开更多
关键词 Hydrothermal vents High pressure-resistant Sample valve Finite element analysis Balanced poppet Bidirectional seal
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Enhancing Accuracy of Flexible Piezoresistive Pressure Sensors by Suppressing Seebeck Effect
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作者 SUI Jingliang DU Minzhi +4 位作者 JING Yuanyuan YANG Xiaona WAN Xuefen YANG Yi ZHANG Kun 《Journal of Donghua University(English Edition)》 CAS 2021年第6期498-503,共6页
Flexible piezoresistive pressure sensors can offer convenient detection of mechanical deformations for wearable electronics.Previous studies of flexible piezoresistive pressure sensors focus on the sensitivity but the... Flexible piezoresistive pressure sensors can offer convenient detection of mechanical deformations for wearable electronics.Previous studies of flexible piezoresistive pressure sensors focus on the sensitivity but the low-cost and self-powered sensors remain a challenge due to the deviation of resistance signal acquisition caused by thermoelectric voltage.Here,piezoresistive pressure sensors with ultralow Seebeck coefficient of-0.72μV/K based on carbon nanotubes(CNTs)/polyethyleneimine(PEI)/melamine(CPM)sponge are reported.Due to the diminished Seebeck effect,the CPM sponge pressure sensors successfully reduce the deviation to 18.75%and can keep stable sensitivity and resistance change under a very low working voltage and change temperature environment.The stable properties of the sensors make them successful to work for real-time sensing in self-powered wearable electronics. 展开更多
关键词 piezoresistive pressure sensor carbon nanotube(CNT) Seebeck effect deviation in resistance measurement thermoelectric voltage
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Control of multidrug-resistant planktonic Acinetobacter baumannii:biocidal efficacy study by atmospheric-pressure air plasma
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作者 Zhe RUAN Yajun GUO +9 位作者 Jing GAO Chunjun YANG Yan LAN Jie SHEN Zimu XU Cheng CHENG Xinghao LIU Shumei ZHANG Wenhui DU Paul K CHU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第6期172-179,共8页
In this research,an atmospheric-pressure air plasma is used to inactivate the multidrug-resistant Acinetobacter baumannii in liquid.The efficacy of the air plasma on bacterial deactivation and the cytobiological varia... In this research,an atmospheric-pressure air plasma is used to inactivate the multidrug-resistant Acinetobacter baumannii in liquid.The efficacy of the air plasma on bacterial deactivation and the cytobiological variations after the plasma treatment are investigated.According to colony forming units,nearly all the bacteria(6-log) are inactivated after 10 min of air plasma treatment.However,7% of the bacteria enter a viable but non-culturable state detected by the resazurin based assay during the same period of plasma exposure.Meanwhile,86% of the bacteria lose their membrane integrity in the light of SYTO 9/PI staining assay.The morphological changes in the cells are examined by scanning electron microscopy and bacteria with morphological changes are rare after plasma exposure in the liquid.The concentrations of the long-living RS,such as H2O2,NO3^- and O3,in liquid induced by plasma treatment are measured,and they increase with plasma treatment time.The changes of the intracellular ROS may be related to cell death,which may be attributed to oxidative stress and other damage effects induced by RS plasma generated in liquid.The rapid and effective bacteria inactivation may stem from the RS in the liquid generated by plasma and air plasmas may become a valuable therapy in the treatment of infected wounds. 展开更多
关键词 ATMOSPHERIC-pressure air plasma multidrug-resistant bacteria Acinetobacter baumannii inactivation reactive species
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A static resistance model and the discontinuous pattern of hydrocarbon accumulation in tight oil reservoirs 被引量:5
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作者 Sun Liang Zou Caineng +2 位作者 Liu Xiaoli Zhu Rukai Wang Xiaoqi 《Petroleum Science》 SCIE CAS CSCD 2014年第4期469-480,共12页
In exploration for tight oil, the content and saturation of hydrocarbon in the tight reservoir is a key factor for evaluating the reserve. Therefore, it is necessary to study the geological history of hydrocarbon accu... In exploration for tight oil, the content and saturation of hydrocarbon in the tight reservoir is a key factor for evaluating the reserve. Therefore, it is necessary to study the geological history of hydrocarbon accumulation and the tight oil charging process. However, kinetic models used for petroleum development are not applicable for petroleum exploration. In this study, a static resistance model[ is proposed after analyzing resistances in ultra-slow flow in porous media. Using this model, the disco^atinuous pattern of oil charging is reproduced through incompressible Navier-Stokes equations, the phase field method and the finite element method. This study also explains macroscopic percolation behavior with microscopic flow mechanisms and discusses some issues in ultra-slow flow in a micro/nano pore-throat network. The resistance analysis reveals that capillary resistance and dissipation resistance are dominant factors in the mechanism of oil accumulation in tight reservoirs. Numerical simulations show that pressure thresholds exist and result in discontinuous oil charging. Generally, it is proven that the static model is more applicable than kinetic models in describing oil accumulation in tight reservoirs. 展开更多
关键词 Tight oil oil charging WETTABILITY capillary pressure static resistance pressure threshold
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Experimental and analytical investigation on friction resistance force between buried coated pressurized steel pipes and soil
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作者 Shaurav ALAM Tanvir MANZUR +4 位作者 John MATTHEWS Chris BARTLETT Erez ALLOUCHE Brent KEIL John KRAFT 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2024年第4期615-629,共15页
This paper presents an analytical approach for estimating frictional resistance to pipe movement at soil and external pipe surface of buried coated pressurized steel pipes relative to the internal thrust force.The pro... This paper presents an analytical approach for estimating frictional resistance to pipe movement at soil and external pipe surface of buried coated pressurized steel pipes relative to the internal thrust force.The proposed analytical method was developed based on 36 experiments,which involved three coating types(cement mortar(CM),polyurethane type-I(PT-I),prefabricated plastic tape(PPT))on pipes’surfaces,three different soils(pea-gravel(PG),sand(S),silty-clay(SC)),and four simulated over burden depths above the pipe’s crown.Investigation showed frictional resistance decreased with increasing over burden depth above the pipe’s crown.The degree of frictional resistance at the pipe-soil interface was found to be in the order of PG>SC>S for all coating variations and overburden depths.CM coated pipe buried in all three types of soil produced significantly higher frictional resistance as compared to other coating types.Based on experimental data,the developed analytical introduced a dimensionless factor“Z”,which included effects of types of coatings,soil,and overburden depths for simplified rapid calculation.Analysis showed that the method provided a better prediction of frictional resistance forces,in comparison to previous analytical methods,which were barely close in predicting friction resistance for different coating variations,soil types,and overburden depths.Friction resistance force values reported herein could be considered conservative. 展开更多
关键词 friction resistance force thrust force coated pressurized steel pipe soil type overburden depth
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