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Barriers to Physical Activity among Children and Adolescents with Intellectual Disabilities: A Cross-sectional Study
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作者 WANG Yu JIN Qiu Meng +3 位作者 WANG Chao HE Gang LI Dong Sheng MA Kai Yue 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第12期1177-1182,共6页
Regular physical activity (PA) has numerous advantages in improving the physical and mental health of children and adolescents^([1]).However,the PA status quo for children and adolescents with intellectual disabilitie... Regular physical activity (PA) has numerous advantages in improving the physical and mental health of children and adolescents^([1]).However,the PA status quo for children and adolescents with intellectual disabilities (ID) is dismal.Children and adolescents with ID frequently exhibit sedentary behaviors because their physical,sensory,and/or cognitive impairments make it difficult to participate in sports and games with their peers^([2]).They have higher rates of mental illness,obesity,type 2diabetes,and other health problems than peers with typical development (TD). 展开更多
关键词 IMPAIRMENT OBESITY sectional
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Clinical nursing value of predictive nursing in reducing complications of pregnant women undergoing short-term massive blood transfusion during cesarean section 被引量:1
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作者 Li Cheng Li-Ping Li +2 位作者 Yuan-Yuan Zhang Fang Deng Ting-Ting Lan 《World Journal of Clinical Cases》 SCIE 2024年第1期51-58,共8页
BACKGROUND Cesarean hemorrhage is one of the serious complications,and short-term massive blood transfusion can easily cause postoperative infection and physical stress response.However,predictive nursing intervention... BACKGROUND Cesarean hemorrhage is one of the serious complications,and short-term massive blood transfusion can easily cause postoperative infection and physical stress response.However,predictive nursing intervention has important clinical significance for it.AIM To explore the effect of predictive nursing intervention on the stress response and complications of women undergoing short-term mass blood transfusion during cesarean section(CS).METHODS A clinical medical record of 100 pregnant women undergoing rapid mass blood transfusion during sections from June 2019 to June 2021.According to the different nursing methods,patients divided into control group(n=50)and observation group(n=50).Among them,the control group implemented routine nursing,and the observation group implemented predictive nursing intervention based on the control group.Moreover,compared the differences in stress res-ponse,complications,and pain scores before and after the nursing of pregnant women undergoing rapid mass blood transfusion during CS.RESULTS The anxiety and depression scores of pregnant women in the two groups were significantly improved after nursing,and the psychological stress response of the observation group was significantly lower than that of the control group(P<0.05).The heart rate and mean arterial pressure(MAP)of the observation group during delivery were lower than those of the control group,and the MAP at the end of delivery was lower than that of the control group(P<0.05).Moreover,different pain scores improved significantly in both groups,with the observation group considerably less than the control group(P<0.05).After nursing,complications such as skin rash,urinary retention,chills,diarrhea,and anaphylactic shock in the observation group were 18%,which significantly higher than in the control group(4%)(P<0.05).CONCLUSION Predictive nursing intervention can effectively relieve the pain,reduce the incidence of complications,improve mood and stress response,and serve as a reference value for the nursing of women undergoing rapid mass transfusion during CS. 展开更多
关键词 Predictive care Rapid mass blood transfusion Cesarean section Stress response COMPLICATIONS
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Proper interpretation of sectional analysis results 被引量:1
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作者 Juyuan Zheng Yuli Huang Zhe Qu 《Earthquake Research Advances》 CSCD 2024年第2期65-71,共7页
Displacement control algorithms commonly used to evaluate axial force-bending moment(PM)diagrams may lead to incorrect interpretations of the strength envelopes for asymmetric sections.This paper aims to offer valuabl... Displacement control algorithms commonly used to evaluate axial force-bending moment(PM)diagrams may lead to incorrect interpretations of the strength envelopes for asymmetric sections.This paper aims to offer valuable insights by comparing existing displacement control algorithms with a newly proposed force control algorithm.The main focus is on the PM diagrams of three example sections that exhibit varying degrees of asymmetry.The comparative study indicates that conventional displacement control algorithms inevitably introduce non-zero out-of-plane bending moments.The reported PM diagram in such cases erroneously neglects the out-of-plane moment and fails to represent the strength envelope accurately.This oversight results in significant and unconservative errors when verifying the strength of asymmetric sections. 展开更多
关键词 Fiber section model Axial force-moment interaction diagram Limit state Failure surface
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Effect of Height Adjusted Dose of Intrathecal Hyperbaric Bupivacine for Elective Cesarean Section: A Study of 2 Different Concentrations
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作者 Mohamed Fouad Mohamed Elmeliegy Mohamed Said Mostafa Elmeligy 《Open Journal of Anesthesiology》 2023年第12期241-253,共13页
Introduction: Study compare spinal anesthesia using hyperbaric bupivacine (0.5% - 0.75%) between fixed dose and height adjusted dose during elective cesarean section. Methods: Hundred parturients who had given their c... Introduction: Study compare spinal anesthesia using hyperbaric bupivacine (0.5% - 0.75%) between fixed dose and height adjusted dose during elective cesarean section. Methods: Hundred parturients who had given their consent and were scheduled for elective cesarean section under spinal anesthesia, were divided into four groups—first group received 0.5% hyperbaric bupivacine fixed dose, the second group received 0.5% hyperbaric bupivacine in a dose adjusted to the height, the third received 0.75% hyperbaric bupivacine fixed dose, the fourth group received 0.75% hyperbaric bupivacine in a dose adjusted to height. The anesthesia onset time, haemodynamic changes, side effects and fetal outcome observed. Results: Spinal block provide excellent surgical anesthesia in all patients. Anesthesia onset time is longer in adjusted than fixed groups, in 0.5% (5 ± 0.816 vs. 3.84 ± 0.746) (P Conclusion: Adjusting dose of hyperbaric bupivacine (0.5% - 0.75%) to patient’s height, decreases the dose of bupivacine in use, it also provide adequate anesthesia for elective cesarean section with decrease the use of vasopressors, the incidence and severity of maternal hypotention also markedly reduced. 展开更多
关键词 Cesarean section HEIGHT Spinal Anesthesia Local Anesthesia
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Growth, Mortality and Stock Assessment of Squaliobarbus curriculus (Actinopterygii: Cypriniformes: Xenocyprididae) from Lanxi Section of Qiantang River, China
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作者 Aiju Zhang Wei Luo +4 位作者 Zhiming Zhou Aihuan Guo Qinping Lian Pengcheng Sheng Julin Yuan 《Open Journal of Animal Sciences》 2023年第3期298-309,共12页
Population dynamics parameters and stock status of Squaliobarbus curriculus (Richardson, 1846) were analyzed from May to September 2021 in the Lanxi section of Qiantang River. FiSAT II software program was used. The g... Population dynamics parameters and stock status of Squaliobarbus curriculus (Richardson, 1846) were analyzed from May to September 2021 in the Lanxi section of Qiantang River. FiSAT II software program was used. The growth coefficient K = 0.21 year<sup>–1</sup>, asymptomatic length L<sub>∞</sub> = 39.48 cm, and age at theoretical zero-length t<sub>0</sub> = –0.74 years were estimated. The von Bertalanffy growth function was calculated as L<sub>t</sub> = 39.48[1 – e<sup>–</sup><sup>0.21(t + 0.74)</sup>]. The growth curve for weight had an inflection at 5.86 years, corresponding to 29.61 cm in standard length and 372.29 g in weight. The natural mortality rate (M), the fishing mortality rate (F), and the total mortality rate (Z) were calculated as 0.51, 0.61, and 1.12 year<sup>–1</sup>, respectively. The exploitation ratio (E) was 0.54, which is greater than the value of 0.5 suggested by Gull (1971), indicating a probable state of overdevelopment. The annual average stock number and biomass of S. curriculus in the Lanxi section of Qiantang River were 31.86 × 10<sup>6</sup> individuals and 3656.82 t, respectively. 展开更多
关键词 Lanxi section of Qiantang River Population Dynamics Parameters Squaliobarbus curriculus Stock Assessment
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Associations of Perchlorate,Nitrate,and Thiocyanate with Sex Hormones among Children:A Nationally Representative Cross-sectional Study in U.S.
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作者 Yiwen Wang Guodong Ding +1 位作者 Peipei Hu Yongjun Zhang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第6期666-671,共6页
Nitrates,thiocyanates,and perchlorates are ubiquitous in the environment and can be introduced to the public through various dietary and environmental sources.Nitrates,thiocyanates,and perchlorates mainly affect healt... Nitrates,thiocyanates,and perchlorates are ubiquitous in the environment and can be introduced to the public through various dietary and environmental sources.Nitrates,thiocyanates,and perchlorates mainly affect health via the same mechanism.These toxins may act as endocrine disrupters and can result in decreased levels of thyroid hormones^([1]). 展开更多
关键词 mechanism sectional PERCHLORATE
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Three-dimensional crystal defect imaging by STEM depth sectioning
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作者 Ryo Ishikawa Naoya Shibata Yuichi Ikuhara 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期2-7,共6页
One of the major innovations awaiting in electron microscopy is full three-dimensional imaging at atomic resolution.Despite the success of aberration correction to deep sub-angstrom lateral resolution,spatial resoluti... One of the major innovations awaiting in electron microscopy is full three-dimensional imaging at atomic resolution.Despite the success of aberration correction to deep sub-angstrom lateral resolution,spatial resolution in depth is still far from atomic resolution.In scanning transmission electron microscopy(STEM),this poor depth resolution is due to the limitation of the illumination angle.To overcome this physical limitation,it is essential to implement a next-generation aberration corrector in STEM that can significantly improve the depth resolution.This review discusses the capability of depth sectioning for three-dimensional imaging combined with large-angle illumination STEM.Furthermore,the statistical analysis approach remarkably improves the depth resolution,making it possible to achieve three-dimensional atomic resolution imaging at oxide surfaces.We will also discuss the future prospects of three-dimensional imaging at atomic resolution by STEM depth sectioning. 展开更多
关键词 atomic-resolution STEM STEM depth sectioning depth resolution DOPANTS surface topography
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Numerical simulation of flow field deposition and erosion characteristics around bridge-road transition section
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作者 ZHANG Kai WANG Zhenghui +3 位作者 WANG Tao TIAN Jianjin ZHANG Hailong LIU Yonghe 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1491-1508,共18页
Wind-sand flow generates erosion and deposition around obstacles such as bridges and roadbeds, resulting in sand damage and endangering railway systems in sandy regions. Previous studies have mainly focused on the flo... Wind-sand flow generates erosion and deposition around obstacles such as bridges and roadbeds, resulting in sand damage and endangering railway systems in sandy regions. Previous studies have mainly focused on the flow field around roadbeds, overlooking detailed examinations of sand particle erosion and deposition patterns near bridges and roadbeds. This study employs numerical simulations to analyze the influence of varying heights and wind speeds on sand deposition and erosion characteristics at different locations: the bridge-road transition section(side piers), middle piers, and roadbeds. The results show that the side piers, experience greater accumulation than the middle piers. Similarly, the leeward side of the roadbed witnesses more deposition compared to the windward side. Another finding reveals a reduced sand deposition length as the vertical profile, in alignment with the wind direction, moves further from the bridge abutments at the same clearance height. As wind speeds rise, there’s a decline in sand deposition and a marked increase in erosion around the side piers, middle piers and roadbeds. In conclusion, a bridge clearance that’s too low can cause intense sand damage near the side piers, while an extremely high roadbed may lead to extensive surface sand deposition. Hence, railway bridges in areas prone to sandy winds should strike a balance in clearance height. This research provides valuable guidelines for determining the most suitable bridge and roadbed heights in regions affected by wind and sand. 展开更多
关键词 SANDSTORM Flow field Bridge-road transition section Sedimentation erosion Numerical simulation
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State-selective charge exchange cross sections in collisions of highly-charged sulfur ions with helium and molecular hydrogen
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作者 朱小龙 崔述成 +9 位作者 邢大地 徐佳伟 B.Najjari 赵冬梅 郭大龙 高永 张瑞田 苏茂根 张少锋 马新文 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期29-33,共5页
The state-selective cross section data are useful for understanding and modeling the x-ray emission in celestial observations.In the present work,using the cold target recoil ion momentum spectroscopy,for the first ti... The state-selective cross section data are useful for understanding and modeling the x-ray emission in celestial observations.In the present work,using the cold target recoil ion momentum spectroscopy,for the first time we investigated the state-selective single electron capture processes for S^(q+)–He and H_(2)(q=11–15)collision systems at an impact energy of q×20 keV and obtained the relative state-selective cross sections.The results indicate that only a few principal quantum states of the projectile energy level are populated in a single electron capture process.In particular,the increase of the projectile charge state leads to the population of the states with higher principal quantum numbers.It is also shown that the experimental averaged n-shell populations are reproduced well by the over-barrier model.The database is openly available in Science Data Bank at 10.57760/sciencedb.j00113.00091. 展开更多
关键词 highly charged sulfur ion charge exchange state-selective cross sections COLTRIMS
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Absolute partial and total ionization cross sections of carbon monoxide with electron collision from 350 eV to 8000 eV
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作者 Taj Wali Khan 黄伟哲 +2 位作者 王恩亮 单旭 陈向军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期459-464,共6页
The absolute partial and total cross sections for electron impact ionization of carbon monoxide are reported for electron energies from 350 eV to 8000 eV.The product ions(CO^(+),C^(+),O^(+),CO^(2+),C^(2+),and O^(2+))a... The absolute partial and total cross sections for electron impact ionization of carbon monoxide are reported for electron energies from 350 eV to 8000 eV.The product ions(CO^(+),C^(+),O^(+),CO^(2+),C^(2+),and O^(2+))are measured by employing an ion imaging mass spectrometer and two ion-pair dissociation channels(C^(+)+O^(+)and C^(2+)+O^(+))are identified.The absolute cross sections for producing individual ions and their total,as well as for the ion-pair dissociation channels are obtained by normalizing the data of CO^(+)to that of Ar^(+)from CO-Ar mixture target with a fixed 1:1 ratio.The overall errors are evaluated by considering various kinds of uncertainties.A comprehensive comparison is made with the available data,which shows a good agreement with each other over the energy ranges that are overlapped.This work presents new cross-section data with electron energies above 1000 eV. 展开更多
关键词 electron impact ionization cross sections carbon monoxide ion imaging mass spectrometer
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Measurement of the neutron-induced total cross sections of ^(nat)Pb from 0.3 eV to 20 MeV on the Back-n at CSNS
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作者 Jie-Ming Xue Song Feng +14 位作者 Yong-Hao Chen Han Yi Min Xiao Pin-Jing Cheng Xin-Xiang Li Rong Liu Yi-Wei Yang Zi-Jie Han Da-Jun Zhao Hao-Qiang Wang Bao-Qian Li Ji-Rong Zhao Lei-Xun Tang Wen Luo Bo Zheng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期85-93,共9页
The neutron-induced total cross sections of natural lead have been measured in a wide energy range(0.3 eV-20 MeV)on the back-streaming white neutron beamline(Back-n)at the China Spallation Neutron Source.Neutron energ... The neutron-induced total cross sections of natural lead have been measured in a wide energy range(0.3 eV-20 MeV)on the back-streaming white neutron beamline(Back-n)at the China Spallation Neutron Source.Neutron energy was determined by the neutron total cross-section spectrometer using the time-of-flight technique.A fast multi-cell fission chamber was used as the neutron detector,and a 10-mm-thick high-purity natural lead sample was employed for the neutron transmission measurements.The on-beam background was determined using Co,In,Ag,and Cd filters.The excitation function of ^(nat)Pb(n,tot)reaction below 20 MeV was calculated using the TALYS-1.96 nuclear-reaction modeling program.The present results were compared with previous results,the evaluated data available in the five major evaluated nuclear data libraries(i.e.,ENDF/B-VIII.0,JEFF-3.3,JENDL-5,CENDL-3.2,and BROND-3.1),and the theoretical calculation curve.Good agreement was found between the new results and those of previous experiments and with the theoretical curves in the corresponding region.This measurement obtained the neutron total cross section of natural lead with good accuracy over a wide energy range and added experimental data in the resonance energy range.This provides more reliable experimental data for nuclear engineering design and nuclear data evaluation of lead. 展开更多
关键词 Neutron-induced total cross section Natural lead TIME-OF-FLIGHT TALYS-1.96 CSNS Back-n white neutron beamline
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THE LOGARITHMIC SOBOLEV INEQUALITY FOR A SUBMANIFOLD IN MANIFOLDS WITH ASYMPTOTICALLY NONNEGATIVE SECTIONAL CURVATURE
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作者 东瑜昕 林和子 陆琳根 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期189-194,共6页
In this note,we prove a logarithmic Sobolev inequality which holds for compact submanifolds without a boundary in manifolds with asymptotically nonnegative sectional curvature.Like the Michale-Simon Sobolev inequality... In this note,we prove a logarithmic Sobolev inequality which holds for compact submanifolds without a boundary in manifolds with asymptotically nonnegative sectional curvature.Like the Michale-Simon Sobolev inequality,this inequality contains a term involving the mean curvature. 展开更多
关键词 asymptotically nonnegative sectional curvature logarithmic Sobolev inequality ABP method
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Taxonomy and phylogeny of the section Chaetoceros(Chaetocerotaceae,Bacillariophyta),with description of two new species
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作者 Xudan LU Mengyi ZHAI +1 位作者 Nina LUNDHOLM Yang LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1286-1311,共26页
Chaetoceros Ehrenberg is one of the most diverse genera of planktonic diatoms.The species in section Chaetoceros are characterized by cells and setae having numerous chloroplasts and being widely distributed.However,t... Chaetoceros Ehrenberg is one of the most diverse genera of planktonic diatoms.The species in section Chaetoceros are characterized by cells and setae having numerous chloroplasts and being widely distributed.However,the delimitations of some species are problematic because of limited morphological information in the classical descriptions.Monoclonal strains of the section Chaetoceros were established,morphological features were studied using light and electron microscopy,and the hypervariable D 1-D 3 region of the nuclear ribosomal large subunit gene was sequenced to address phylogenetic relationships.Fifteen species belonging to the section Chaetoceros were recorded,including two new species,C.hainanensis sp.nov.and C.tridiscus sp.nov.Chaetoceros hainanensis was characterized by straight chains,narrowly lanceolate to hexagonal apertures,sibling setae diverging in nearly right angles,stipule-shaped spines on terminal setae and arrowhead-shaped spines on intercalary setae.C.tridiscus had short straight chains,narrowly lanceolate apertures,arrowhead-shaped spines and circular poroids arranged in a grid pattern on terminal and intercalary setae.The phylogenetic analyses revealed six groups formed by 19 species within the section Chaetoceros,which was found to be monophyletic.The subdivision of the section is still not well understood.The morphological characters within each group varied considerably and molecular information on more species are needed to enrich the phylogenetic profiling. 展开更多
关键词 morphology large subunit ribosomal RNA encoding gene(LSU) section Chaetoceros Chaetoceros hainanensis Chaetoceros tridiscus
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Oscillatory Dynamics of a Spherical Solid in a Liquid in an Axisymmetric Variable Cross Section Channel
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作者 Ivan Karpunin 《Fluid Dynamics & Materials Processing》 EI 2024年第6期1219-1232,共14页
The dynamics of a solid spherical body in an oscillating liquid flow in a vertical axisymmetric channel of variable cross section is experimentally studied.It is shown that the oscillating liquid leads to the generati... The dynamics of a solid spherical body in an oscillating liquid flow in a vertical axisymmetric channel of variable cross section is experimentally studied.It is shown that the oscillating liquid leads to the generation of intense averaged flows in each of the channel segments.The intensity and direction of these flows depend on the dimensionless oscillating frequency.In the region of studied frequencies,the dynamics of the considered body is examined when the primary vortices emerging in the flow occupy the whole region in each segment.For a fixed frequency,an increase in the oscillation amplitude leads to a phase-inclusion holding effect,i.e.,the body occupies a quasi-stationary position in one of the cells of the vertical channel,while oscillating around its average position.It is also shown that the oscillating motion of a liquid column generates an averaged force acting on the body,the magnitude of which depends on the properties of the body and its position in the channel.The quasi-stationary position is determined by the relative density and size of the body,as well as the dimensionless frequency.The behavior of the body as a function of the amplitude and frequency of fluid oscillation and relative size is discussed in detail.Such findings may be used in the future to control the position of a phase inclusion and/or to strengthen mass transfer effects in a channel of variable cross section by means of fluid oscillations. 展开更多
关键词 Phase inclusion axisymmetric channel variable cross section oscillations dimensionless frequency averaged force viscous boundary layer
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Effect of intraoperative injection of esketamine on postoperative analgesia and postoperative rehabilitation after cesarean section
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作者 Hong-Zhuan Chen Yi Gao +4 位作者 Ke-Ke Li Li An Jing Yan Hong Li Jin Zhang 《World Journal of Clinical Cases》 SCIE 2024年第28期6195-6203,共9页
BACKGROUND Following cesarean section,a significant number of women encounter moderate to severe pain.Inadequate management of acute pain post-cesarean section can have far-reaching implications,adversely impacting ma... BACKGROUND Following cesarean section,a significant number of women encounter moderate to severe pain.Inadequate management of acute pain post-cesarean section can have far-reaching implications,adversely impacting maternal emotional wellbeing,daily activities,breastfeeding,and neonatal care.It may also impede maternal organ function recovery,leading to escalated opioid usage,heightened risk of postpartum depression,and the development of chronic postoperative pain.Both the Chinese Enhanced Recovery After Surgery(ERAS)guidelines and the American ERAS Society guidelines consistently advocate for the adoption of multimodal analgesia protocols in post-cesarean section pain management.Esketamine,functioning as an antagonist of the N-Methyl-D-Aspartate receptor,has been validated for pain management in surgical patients and has exhibited effectiveness in depression treatment.Research has suggested that incorporating esketamine into postoperative pain management via pain pumps can lead to improvements in short-term depression and pain outcomes.This study aims to assess the efficacy and safety of administering a single dose of esketamine during cesarean section.AIM To investigate the effect of intraoperative injection of esketamine on postoperative analgesia and postoperative rehabilitation after cesarean section.METHODS A total of 315 women undergoing elective cesarean section under combined spinal-epidural anesthesia were randomized into three groups:low-dose esketamine(0.15 mg/kg),high-dose esketamine(0.25 mg/kg),and control(saline).Postoperative Visual Analog Scale(VAS)scores were recorded at 6 hours,12 hours,24 hours,and 48 hours.Edinburgh Postnatal Depression Scale(EPDS)scores were noted on 2 days,7 days and 42 days.Ramsay sedation scores were assessed at specified intervals post-injection.Postoperative adverse reactions were also recorded.RESULTS Low-dose group and high-dose group compared to control group,had significantly lower postoperative VAS pain scores at 6 hours 12 hours,and 24 hours(P<0.05),with reduced analgesic usage(P<0.05).EPDS scores and postpartum depression rates were significantly lower on 2 days and 7 days(P<0.05).No significant differences in first exhaust and defecation times were observed(P>0.05),but ambulation times were shorter(P<0.05).Ramsay scores were higher at 5 minutes,15 minutes,and upon room exit(P<0.05).Low-dose group and high-dose group had higher incidences of hallucination,lethargy,and diplopia within 2 hours(P<0.05),and with low-dose group had lower incidences of hallucination,lethargy,and diplopia than high-dose group(P<0.05).CONCLUSION Esketamine enhances analgesia and postpartum recovery;a 0.15 mg/kg dose is optimal for cesarean sections,balancing efficacy with minimized adverse effects. 展开更多
关键词 MATERNITY Cesarean section DEPRESSION Esketamine Postoperative analgesia
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Highly Accurate Golden Section Search Algorithms and Fictitious Time Integration Method for Solving Nonlinear Eigenvalue Problems
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作者 Chein-Shan Liu Jian-Hung Shen +1 位作者 Chung-Lun Kuo Yung-Wei Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1317-1335,共19页
This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solve... This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solved from a nonhomogeneous linear system obtained by reducing the number of eigen-equation one less,where one of the nonzero components of the eigenvector is normalized to the unit and moves the column containing that component to the right-hand side as a nonzero input vector.1D and 2D golden section search algorithms are employed to minimize the merit functions to locate real and complex eigenvalues.Simultaneously,the real and complex eigenvectors can be computed very accurately.A simpler approach to the nonlinear eigenvalue problems is proposed,which implements a normalization condition for the uniqueness of the eigenvector into the eigenequation directly.The real eigenvalues can be computed by the fictitious time integration method(FTIM),which saves computational costs compared to the one-dimensional golden section search algorithm(1D GSSA).The simpler method is also combined with the Newton iterationmethod,which is convergent very fast.All the proposed methods are easily programmed to compute the eigenvalue and eigenvector with high accuracy and efficiency. 展开更多
关键词 Nonlinear eigenvalue problem quadratic eigenvalue problem two new merit functions golden section search algorithm fictitious time integration method
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Effect of psychological nursing intervention combined with acupressure on postoperative recovery of women after cesarean section
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作者 Xing-Ying Liu Xiao-Bo Chen +2 位作者 You-Liang Wen Xiao-Ping Guo Xiao-Bin Zhou 《World Journal of Clinical Cases》 SCIE 2024年第21期4527-4535,共9页
BACKGROUND Psychological intervention nursing(PIN)has been considered to have a curative effect on cesarean section(CS)post-operative recovery.However,the therapeutic mechanisms remain obscure.AIM To explore the effec... BACKGROUND Psychological intervention nursing(PIN)has been considered to have a curative effect on cesarean section(CS)post-operative recovery.However,the therapeutic mechanisms remain obscure.AIM To explore the effects of PIN combined with acupressure massage on CS postoperative recovery.METHODS A retrospective study was conducted on 150 pregnant women admitted to an obstetrics department between January 2020 and January 2023.The control group(CG)received acupressure therapy(n=73),and the intervention group(IG)received acupressure therapy and PIN therapy(n=77).Postoperative recovery time was assessed by anal-exhausting,defecation,bed activity,breastfeeding,and hospital stay times.Adverse effects,including infection,bleeding,limb numbness,intrauterine hematoma,urinary retention,and venous thromboembolism,were recorded.the pain visual analogue scale(VAS)was used to evaluate the degree of pain.Anxiety and depression status were qualitatively assessed using the selfrating anxiety scale(SAS),self-rating depression scale(SDS),and Edinburgh postpartum depression scale(EPDS).The Pittsburgh sleep quality index(PSQI)was used to compare sleep quality between the groups.RESULTS The baseline data and SAS,SDS,EPDS,and PSQI scores did not significantly differ before CS(P>0.05)and neither did complication rates between the two groups after CS(P>0.05).However,anal-exhausting,defecation,waking up,breastfeeding,and hospitalization times were significantly shorter for participants in the IG than those for participants in the CG(P<0.05).The VAS,SAS,SDS,EPDS,and PSQI scores of the IG were significantly lower than those of the CG(P<0.05).CONCLUSION PIN,combined with acupressure massage,effectively promotes maternal recovery,reduces post-CS pain,and improves post-operative negative emotions and sleeping quality. 展开更多
关键词 Psychological intervention nursing Acupressure massage Cesarean section Negative emotions Sleep quality
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Biomechanical effects of posterior lumbar interbody fusion with vertical placement of pedicle screws compared to traditional placement
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作者 Ji-Hong Jiang Chang-Ming Zhao +2 位作者 Jun Zhang Rong-Ming Xu Lei Chen 《World Journal of Clinical Cases》 SCIE 2024年第20期4108-4120,共13页
BACKGROUND The pedicle screw technique is widely employed for vertebral body fixation in the treatment of spinal disorders.However,traditional screw placement methods require the dissection of paraspinal muscles and t... BACKGROUND The pedicle screw technique is widely employed for vertebral body fixation in the treatment of spinal disorders.However,traditional screw placement methods require the dissection of paraspinal muscles and the insertion of pedicle screws at specific transverse section angles(TSA).Larger TSA angles require more force to pull the muscle tissue,which can increase the risk of surgical trauma and ischemic injury to the lumbar muscles.AIM To study the feasibility of zero-degree TSA vertical pedicle screw technique in the lumbosacral segment.METHODS Finite element models of vertebral bodies and pedicle screw-rod systems were established for the L4-S1 spinal segments.A standard axial load of 500 N and a rotational torque of 10 N/m were applied.Simulated screw pull-out experiment was conducted to observe pedicle screw resistance to pull-out,maximum stress,load-displacement ratio,maximum stress in vertebral bodies,load-displacement ratio in vertebral bodies,and the stress distribution in pedicle screws and vertebral bodies.Differences between the 0-degree and 17-degree TSA were compared.RESULTS At 0-degree TSA,the screw pull-out force decreased by 11.35%compared to that at 17-degree TSA(P<0.05).At 0-degree and 17-degree TSA,the stress range in the screw-rod system was 335.1-657.5 MPa and 242.8-648.5 MPa,separately,which were below the fracture threshold for the screw-rod system(924 MPa).At 0-degree and 17-degree TSA,the stress range in the vertebral bodies was 68.45-78.91 MPa and 39.08-72.73 MPa,separately,which were below the typical bone yield stress range for vertebral bodies(110-125 MPa).At 0-degree TSA,the load-displacement ratio for the vertebral bodies and pedicle screws was slightly lower compared to that at 17-degree TSA,indicating slightly lower stability(P<0.05).CONCLUSION The safety and stability of 0-degree TSA are slightly lower,but the risks of screw-rod system fracture,vertebral body fracture,and rupture are within acceptable limits. 展开更多
关键词 Vertical pedicle screw Pedicle screw technique Transverse section angle Lumbosacral segment Finite element analysis
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Research on uninterruptable power supply technology for auxiliary winding of electric locomotive while passing the neutral section
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作者 Yuliang Du 《Railway Sciences》 2024年第2期128-142,共15页
Purpose–Auxiliary power system is an indispensable part of the train;the auxiliary systems of both electric locomotives and EMUs mainly are powered by one of the two ways,which are either from auxiliary windings of t... Purpose–Auxiliary power system is an indispensable part of the train;the auxiliary systems of both electric locomotives and EMUs mainly are powered by one of the two ways,which are either from auxiliary windings of traction transformers or from DC-link voltage of traction converters.Powered by DC-link voltage of traction converters,the auxiliary systems were maintained of uninterruptable power supply with energy from electric braking.Meanwhile,powered by traction transformers,the auxiliary systems were always out of power while passing the neutral section of power supply grid and control system is powered by battery at this time.Design/methodology/approach–Uninterrupted power supply of auxiliary power system powered by auxiliary winding of traction transformer was studied.Failure reasons why previous solutions cannot be realized are analyzed.An uninterruptable power supply scheme for the auxiliary systems powered by auxiliary windings of traction transformers is proposed in this paper.The validity of the proposed scheme is verified by simulation and experimental results and on-site operation of an upgraded HXD3C type locomotive.This scheme is attractive for upgrading practical locomotives with the auxiliary systems powered by auxiliary windings of traction transformers.Findings–This scheme regenerates braking power supplied to auxiliary windings of traction transformers while a locomotive runs in the neutral section of the power supply grid.Control objectives of uninterrupted power supply technology are proposed,which are no overvoltage,no overcurrent and uninterrupted power supply.Originality/value–The control strategies of the scheme ensure both overvoltage free and inrush current free when a locomotive enters or leaves the neutral section.Furthermore,this scheme is cost low by employing updated control strategy of software and add both the two current sensors and two connection wires of hardware. 展开更多
关键词 Electric locomotive Auxiliary system Neutral section Uninterruptable power supply OVERVOLTAGE Inrush current
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Cross section determination of^(27)Al(n,2n)^(26)Al reaction induced by 14-MeV neutrons uniting with D-T neutron activation and AMS techniques
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作者 Xian-Lin Yang Chang-Lin Lan +6 位作者 Yu-Ting Wei Yi Zhang Gong Jiang Bo Xie Yu Liu Hong-Tao Shen Xiao-Jun Sun 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第6期78-89,共12页
Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great significance.To address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al re... Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great significance.To address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al reaction cross section,the activation method and accelerator mass spectrometry(AMS)technique were used to determine the^(27)Al(n,2n)^(26)Al cross section,which could be used as a D-T plasma ion temperature monitor in fusion reactors.At the China Academy of Engineering Physics,neutron activation was performed using a K-400 neutron generator produced by the T(d,n)4He reaction.The^(26)Al∕^(27)Al isotope ratios were measured using the newly installed GYIG 1 MV AMS at the Institute of Geochemistry,Chinese Academy of Sciences.The neutron flux was monitored by measuring the activity of 92mNb produced by the 93Nb(n,2n)92mNb reaction.The measured results were compared with available data in the experimental nuclear reaction database,and the measured values showed a reasonable degree of consistency with partially available literature data.The newly acquired cross-sectional data at 12 neutron energy points through systematic measurements clarified the divergence,which has two different growth trends from the existing experimental values.The obtained results are also compared with the corresponding evaluated database,and the newly calculated excitation functions with TALYS−1.95 and EMPIRE−3.2 codes,the agreement with CENDL−3.2,TENDL-2021 and EMPIRE−3.2 results are generally acceptable.A substantial improvement in the knowledge of the^(27)Al(n,2n)^(26)Al reaction excitation function was obtained in the present work,which will lay the foundation for the diagnosis of the fusion ion temperature,testing of the nuclear physics model,evaluation of nuclear data,etc. 展开更多
关键词 14-MeV neutron ^(27)Al(n 2n)^(26)Al Cross section AMS
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