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Aerodynamic Features of High-Speed Maglev Trains with Different Marshaling Lengths Running on a Viaduct under Crosswinds
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作者 Zun-Di Huang Zhen-Bin Zhou +2 位作者 Ning Chang Zheng-Wei Chen Su-Mei Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期975-996,共22页
The safety and stability of high-speed maglev trains traveling on viaducts in crosswinds critically depend on their aerodynamic characteristics.Therefore,this paper uses an improved delayed detached eddy simulation(ID... The safety and stability of high-speed maglev trains traveling on viaducts in crosswinds critically depend on their aerodynamic characteristics.Therefore,this paper uses an improved delayed detached eddy simulation(IDDES)method to investigate the aerodynamic features of high-speed maglev trains with different marshaling lengths under crosswinds.The effects of marshaling lengths(varying from 3-car to 8-car groups)on the train’s aerodynamic performance,surface pressure,and the flow field surrounding the train were investigated using the three-dimensional unsteady compressible Navier-Stokes(N-S)equations.The results showed that the marshaling lengths had minimal influence on the aerodynamic performance of the head and middle cars.Conversely,the marshaling lengths are negatively correlated with the time-average side force coefficient(CS)and time-average lift force coefficient(Cl)of the tail car.Compared to the tail car of the 3-car groups,the CS and Cl fell by 27.77%and 18.29%,respectively,for the tail car of the 8-car groups.It is essential to pay more attention to the operational safety of the head car,as it exhibits the highest time average CS.Additionally,the mean pressure difference between the two sides of the tail car body increased with the marshaling lengths,and the side force direction on the tail car was opposite to that of the head and middle cars.Furthermore,the turbulent kinetic energy of the wake structure on the windward side quickly decreased as marshaling lengths increased. 展开更多
关键词 High-speed maglev train marshaling lengths crosswinds aerodynamic features
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Impact of multifocal gas-permeable lens designs on short-term choroidal response, axial length, and retinal defocus profile
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作者 Muteb Alanazi Patrick Caroline +1 位作者 Amane Alshamrani Maria Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期247-256,共10页
AIM:To investigate the impact of multifocal gas permeable contact lens(MFGPCL)in various add power and distance/near area allocation on short-term changes of choroidal thickness(ChT),axial length(AL),and retinal defoc... AIM:To investigate the impact of multifocal gas permeable contact lens(MFGPCL)in various add power and distance/near area allocation on short-term changes of choroidal thickness(ChT),axial length(AL),and retinal defocus profile in young adults.METHODS:Seventeen young adults(2 males and 15 females;age 23.17±4.48y)were randomly assigned to wear two designs binocularly with a one-week washout period in between.Total of four MFGPCL designs were assessed.All designs were distance-center that varied in two add power(+1.50 and 3.00 D)and/or two distance zone(DZ)diameters(1.50 and 3.00 mm;design A:DZ 1.5/add 3.0,B:DZ 1.5/add 1.5,C:DZ 3.0/add 3.0,D:DZ 3.0/add 1.5).ChT,AL,and peripheral refraction data were collected on each subject at baseline,on days 1 and 7 of MFGPCL daily wear.ChT was assessed in four quadrants using a spectraldomain optical coherence tomography.RESULTS:AL was shortened by-26±44μm with lens C,-18±27μm with lens D,-13±29μm with lens A,and-8±30μm with lens B(all P<0.05).A significant overall increase in ChT was observed with all 4 designs(lens A:+6±6μm,B:+3±7μm,C:+8±7μm,and D:+8±7μm).Temporal and superior choroid exhibited more choroidal thickening associated with MFGPCL.All designs induced significant relative peripheral myopia(RPM)beyond the central 20o across the horizontal meridian in both nasal and temporal fields(P<0.05).CONCLUSION:MFGPCLs show a significant influence on ChT and AL,which are associated with significant increase in RPM after short-term wear.The reliability and feasibility of quantifying short-term changes in ChT support its use as a promising marker for the long-term efficacy of myopia-controlling treatments. 展开更多
关键词 CHOROID gas-permeable contact lens retinal defocus axial length MYOPIA
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Exploring the Implications of the Deformation Parameter and Minimal Length in the Generalized Uncertainty Principle
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作者 Mahgoub A. Salih Taysir M. Elmahdi 《Journal of Quantum Information Science》 CAS 2024年第1期1-14,共14页
The breakdown of the Heisenberg Uncertainty Principle occurs when energies approach the Planck scale, and the corresponding Schwarzschild radius becomes similar to the Compton wavelength. Both of these quantities are ... The breakdown of the Heisenberg Uncertainty Principle occurs when energies approach the Planck scale, and the corresponding Schwarzschild radius becomes similar to the Compton wavelength. Both of these quantities are approximately equal to the Planck length. In this context, we have introduced a model that utilizes a combination of Schwarzschild’s radius and Compton length to quantify the gravitational length of an object. This model has provided a novel perspective in generalizing the uncertainty principle. Furthermore, it has elucidated the significance of the deforming linear parameter β and its range of variation from unity to its maximum value. 展开更多
关键词 Generalized Uncertainty Principle Deformed Heisenberg Algebra Minimal length
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Simple bone cysts of the proximal humerus presented with limb length discrepancy:A case report
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作者 Cing Syue Lin Shang Ming Lin +2 位作者 Syang-Peng Rwei Chin-Wen Chen Tsung-Yu Lan 《World Journal of Clinical Cases》 SCIE 2024年第6期1130-1137,共8页
BACKGROUND Simple bone cysts(SBC)are benign tumor-like bone lesions typically identified in children.While SBC may lead to growth disturbances or growth arrest,such cases are uncommon.The mechanisms behind these obser... BACKGROUND Simple bone cysts(SBC)are benign tumor-like bone lesions typically identified in children.While SBC may lead to growth disturbances or growth arrest,such cases are uncommon.The mechanisms behind these observations remain unclear.Additionally,research on the etiology of SBC remains inconclusive,and there has been no consensus on the appropriate timing and methodology for treatment.CASE SUMMARY Here,we present our experience in the successful surgical management of a 10-year-old girl with SBC,who presented with a pathological fracture complicated by malunion of the displaced fracture,varus deformity,and limb length discrepancy.We hypothesized two possible etiologies for the patient’s growth arrest and subsequent humerus varus deformity:(1)Direct disruption of the physis by fluid from the cyst itself;and(2)damage to the epiphysis due to repetitive pathological fractures associated with SBC.In addressing this case,surgical intervention was undertaken to correct the proximal humerus varus deformity.This approach offered the advantages of simultaneously correcting angular abnormalities,achieving mild limb lengthening,providing definitive SBC treatment,and reducing the overall treatment duration.CONCLUSION As per current literature,acute correction of acute angular deformity in proximal humeral SBC is not well comprehended.However,in this specific case,acute correction was considered an optimal solution. 展开更多
关键词 Bone cyst Solitary cysts BENIGN HUMERUS Growth arrest Limb length discrepancy Case report
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Nonlinear Relationship and Its Evolutionary Trace between Node Degree and Average Path Length of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Zhang Xiaoxuan Li Yangqi 《Journal of Traffic and Transportation Engineering》 2024年第1期11-22,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the node degree and the average path length of China aviation network in 1988,1994,2001... In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the node degree and the average path length of China aviation network in 1988,1994,2001,2008 and 2015 was studied.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network.On the basis of the statistical data,the node average path length of China aviation network in 1988,1994,2001,2008 and 2015 was calculated.Through regression analysis,it was found that the node degree had a logarithmic relationship with the average length of node path,and the two parameters of the logarithmic relationship had linear evolutionary trace.Key word:China aviation network,complex network,node degree,average length of node path,logarithmic relationship,evolutionary trace. 展开更多
关键词 China aviation network complex network node degree average length of node path logarithmic relationship evolutionary trace.
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E-Cervix弹性成像评估不同分娩史孕妇妊娠期宫颈组织差异的研究
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作者 杜柳 古裕均 +2 位作者 吴利红 张立鹤 谢红宁 《影像诊断与介入放射学》 2024年第1期63-70,共8页
目的探讨不同分娩方式生育史孕妇宫颈E-Cervix参数随孕周的变化规律,以及不同分娩方式对再次妊娠时的宫颈软硬度和长度的影响。方法前瞻性收集2022年6月—2023年6月在我院定期产检的单胎妊娠孕妇,分别于11~14周、20~24周、28~32周经阴... 目的探讨不同分娩方式生育史孕妇宫颈E-Cervix参数随孕周的变化规律,以及不同分娩方式对再次妊娠时的宫颈软硬度和长度的影响。方法前瞻性收集2022年6月—2023年6月在我院定期产检的单胎妊娠孕妇,分别于11~14周、20~24周、28~32周经阴道超声测量孕妇宫颈的E-Cervix弹性参数。根据既往有无生育史及分娩方式,将研究对象分为初产妇组(A组)、经产妇无剖宫产史组(B组)和经产妇合并剖宫产史组(C组)。采用Friedman检验比较各组孕妇3个孕周段各宫颈参数值的差异,Mann-Whitney U检验比较初产妇与经产妇无剖宫产史及经产妇合并剖宫产史的宫颈各参数值差异。结果共纳入191例孕妇,其中A组101例,B组49例,C组41例。A组宫颈弹性值3个孕周段的差异均具有统计学意义(P<0.05);B组除应变比值(Ratio)外,余宫颈弹性值在3个孕周段的差异均具有统计学意义(P<0.05);C组除弹性对比指数(ECI)及Ratio外,余宫颈弹性值在3个孕周段的差异均具有统计学意义(P<0.05)。随着孕周段的增加,3组硬度比值(HR)逐渐减小,宫颈内口平均应变值(IOS)、宫颈外口平均应变值(EOS)逐渐增大。A组3个孕周段宫颈长度(CL)值中位数分别为3.36、3.51、3.49(P<0.05);B组3个孕周段CL值中位数分别为3.27、3.58、3.50(P<0.05);C组3个孕周段CL值中位数分别为3.38、3.73、3.63(P=0.057)。3组孕妇宫颈长度呈现出先增长再缩短的发展趋势。中孕期A组ECI值中位数小于B组(2.34比2.63),HR值中位数大于B组(89.81%比87.20%),CL值中位数小于C组(3.51比3.73),且差异均有统计学意义(P=0.008、P=0.024、P=0.034)。早孕期及晚孕期各项宫颈参数值在A组与B组及A组与C组间的差异均无明显统计学意义(P>0.05)。结论E-Cervix技术客观地反映出不同分娩方式生育史孕妇妊娠期宫颈组织随孕周增加均产生一系列生理变化。不同分娩方式会影响再次妊娠时的宫颈弹性和宫颈长度的变化,中孕期经产妇无剖宫产史孕妇宫颈组织较初产妇软且均质性差,经产妇合并剖宫产史孕妇宫颈长度明显长于初产妇。 展开更多
关键词 宫颈 弹性超声成像 宫颈长度 分娩方式
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Fine mapping and candidate gene analysis of qGL10 affecting rice grain length 被引量:1
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作者 Tengkui Chen Lixin Luo +6 位作者 Zhe Zhao Hui Wang Chun Chen Yongzhu Liu Xinchang Li Tao Guo Wuming Xiao 《The Crop Journal》 SCIE CSCD 2023年第2期540-548,共9页
Grain size influences the yield and quality of rice(Oryza sativa L.),and grain length is one of the component traits of grain size.In this study,a near-isogenic line LB3 with long grain size was constructed using japo... Grain size influences the yield and quality of rice(Oryza sativa L.),and grain length is one of the component traits of grain size.In this study,a near-isogenic line LB3 with long grain size was constructed using japonica rice cultivar 02428,with short grain size,as the recipient parent and indica rice cultivar ZYX,with long grain size,as the donor parent,by multi-generation backcrossing and selfing.BSA-seq was used for preliminary QTL mapping and InDel markers were developed to fine map the locus.The major QTL,tentatively named qGL10,for grain length was located in a 128.45 kb region of chromosome 10.Combined with haplotype analysis of rice varieties,expression pattern analysis of candidate genes suggested LOC_Os10g39130(OsMADS56)as a candidate gene.Sequence alignment of OsMADS56 in 02428 and LB3 revealed that there were 15 SNPs in the promoter region and four in the coding region.Further haplotype analysis suggested that SNP9(G/A)located in the TGTCACA motif might account for the different expression levels of OsMADS56 in 02428 and LB3.These results lay a foundation for the application of qGL10 in molecular breeding of new rice varieties. 展开更多
关键词 RICE Grain length QTL mapping Haplotype analysis
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The impact of emergency department length of stay on the outcomes of trauma patients requiring hospitalization: a retrospective observational study 被引量:1
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作者 Ahmed Faidh Ramzee Ayman El-Menyar +7 位作者 Mohammad Asim Ahad Kanbar Khalid Ahmed Bahaa Daoud Saji Mathradikkal Ahmad Kloub Hassan Al-Thani Sandro Rizoli 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第2期96-105,共10页
BACKGROUND: We aimed to explore the impact of the emergency department length of stay(EDLOS) on the outcome of trauma patients.METHODS: A retrospective study was conducted on all trauma patients requiring hospitalizat... BACKGROUND: We aimed to explore the impact of the emergency department length of stay(EDLOS) on the outcome of trauma patients.METHODS: A retrospective study was conducted on all trauma patients requiring hospitalization between 2015 and 2019. Patients were categorized into 4 groups based on the EDLOS(<4 h, 4–12 h,12–24 h, and >24 h). Data were analyzed using Chi-square test(categorical variables), Student’s t-test(continuous variables), correlation coefficient, analysis of variance and multivariate logistic regression analysis for identifying predictors of short EDLOS and hospital mortality.RESULTS: The study involved 7,026 patients with a mean age of 32.1±15.6 years. Onefifth of patients had a short EDLOS(<4 h) and had higher level trauma team T1 activation(TTA-1), higher Injury Severity Score(ISS), higher shock index(SI), and more head injuries than the other groups(P=0.001). Patients with an EDLOS >24 h were older(P=0.001) and had more comorbidities(P=0.001) and fewer deaths(P=0.001). Multivariate regression analysis showed that the predictors of short EDLOS were female gender, GCS, SI, hemoglobin level, ISS, and blood transfusion. The predictors of mortality were TTA-1(odds ratio [OR]=4.081, 95%CI: 2.364–7.045), head injury(OR=3.920, 95%CI: 2.413–6.368), blood transfusion(OR=2.773, 95%CI: 1.668–4.609), SI(OR=2.132, 95%CI: 1.364–3.332), ISS(OR=1.077, 95%CI: 1.057–1.096), and age(OR=1.040, 95%CI: 1.026–1.054). CONCLUSIONS: Patients with shorter EDLOS had different baseline characteristics and hospital outcomes compared with patients with longer EDLOS. Patients with prolonged EDLOS had better outcomes;however, the burden of prolonged boarding in the ED needs further elaboration. 展开更多
关键词 Emergency department length of stay TRAUMA Management OUTCOMES Trauma activation criteria
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Correlation of serum albumin level on postoperative day 2 with hospital length of stay in patients undergoing emergency surgery for perforated peptic ulcer 被引量:1
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作者 Dan Xie Ping-Lan Lu +3 位作者 Wen Xu Jing-Ya You Xiao-Gang Bi Ying Xian 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第7期1434-1441,共8页
BACKGROUND Perforated peptic ulcer(PPU)is a common emergency surgical condition and a significant cause of morbidity and mortality worldwide.While advances in surgical techniques have improved outcomes for patients wi... BACKGROUND Perforated peptic ulcer(PPU)is a common emergency surgical condition and a significant cause of morbidity and mortality worldwide.While advances in surgical techniques have improved outcomes for patients with PPU,many factors still affect postoperative hospital stay and overall prognosis.One potential factor is the serum albumin(SA)level,a widely utilized marker of nutritional status that has been associated with length of stay and complications in various surgical procedures.AIM To clarify the correlation of SA level on postoperative day 2 with hospital length of stay(HLOS)in patients undergoing emergency surgery for perforated peptic ulcer(PPU).METHODS We retrospectively collected and analyzed clinical baseline data,including blood routine and SA levels,of patients who underwent emergency PPU surgery and postoperative treatment at the Lingnan Hospital,the Third Affiliated Hospital of Sun Yat-sen University between December 2012 and September 2021.Patients were grouped according to HLOS with 7 d as the cut-off value,and relevant indicators were analyzed using SPSS 26.0.RESULTS Of the 37 patients undergoing emergency surgery for PPU referred to our department,33 had gastric and 4 had duodenal ulcer perforation.The median HLOS was 10 d.There were 8 patients in the≤7-d group(median HLOS:7 d)and 29 patients in the>7-d group(median HLOS:10 d).The≤7-d group had markedly higher SA on postoperative day 2 than the>7-d group(37.7 g/L vs 32.6g/L;P<0.05).The SA level on postoperative day 2 was a protective factor for patients with HLOS>7 d(Odds ratio=0.629,P=0.015).The cut-off of SA on postoperative day 2 was 30.6g/L,with an area under the curve of 0.86 and a negative predictive value of 100%for the prediction of HLOS≤7 d.CONCLUSION The SA level on postoperative day 2 was associated with the HLOS in patients undergoing emergency surgery for PPU.The pre-and post-operative albumin levels should be monitored,and infusion of human SA should be considered in a timely manner. 展开更多
关键词 Perforated peptic ulcer Emergency surgery Serum albumin Hospital length of stay
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Equalisation of Lower Limb Length in Young Adults Using Internal Osteosynthesis: A Case Report of 22 Patients
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作者 Mohamed Idrissa Seidou Issa Soumana Yahaya +3 位作者 Ali Moussa Niandou Abassa Seyni Zirbine Adoul Aziz Seini Badio Seyni Souna Badio 《Open Journal of Orthopedics》 2023年第8期335-342,共8页
Introduction: Inequality in the length of the lower limbs has an impact on the stability and function of the musculoskeletal system because of the imbalance it causes in our bodies. Several treatment modalities were u... Introduction: Inequality in the length of the lower limbs has an impact on the stability and function of the musculoskeletal system because of the imbalance it causes in our bodies. Several treatment modalities were used by practitioners. The aim of this study was to evaluate the anatomical and functional results of length equalisation of the lower limbs using internal osteosynthesis in the Orthopaedic and Traumatological Surgery Department of the Amirou Boubacar Diallo National Hospital in Niamey. Patients and method: This was a retrospective, prospective study of 22 patients from January 2010 to November 2015, a period of 5 years. The patients concerned were aged at least 18 years and had undergone a femoral shortening osteotomy not exceeding 5 cm on the contralateral healthy limb with a screw plate as the internal osteosynthesis device. Results: The average age of our patients was 24.18 years (18 to 48 years). The etiologies of these length inequalities were: vascular 54.55% (n = 12), post-traumatic 27.27% (n = 6), post-infectious 13.64% (n = 3) and neuromuscular 4.54% (n = 1). The mean length inequality of our patients was 4.93 cm, with extremes ranging from 4 to 8 cm. At an average follow-up of 6.5 months (6 to 24 months), our functional results were satisfactory overall. Discussion: Despite the significant nature of our initial inequalities, which were moderate and severe, we ended up with slight inequalities or even total correction for some of our patients. Conclusion: Inequality in the length of the lower limbs is a handicap that requires appropriate management. 展开更多
关键词 EQUALISATION length Lower Limb Internal Osteosynthesis
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Dynamic Analysis of A Deep-Water Compliant Vertical Access Riser with A Variable Length During Installation
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作者 LIANG Wei-xing LOU Min +1 位作者 WANG Yu ZHANG Rui 《China Ocean Engineering》 SCIE EI CSCD 2023年第4期568-579,共12页
Compliant vertical access risers(CVAR)have broad application prospects in deep-water oil and gas transportation.However,the mechanical behaviors of the CVAR with a variable length during installation remains unclear.T... Compliant vertical access risers(CVAR)have broad application prospects in deep-water oil and gas transportation.However,the mechanical behaviors of the CVAR with a variable length during installation remains unclear.To address this issue,based on the flexible segment method,a model of CVAR with a variable length during installation is established in this study,which is verified by the comparison with commercial software.Then,the mechanical behaviors of CVAR during installation are investigated.The results reveal that the CVAR configuration is significantly affected by the buoyancy blocks.The streamwise displacement of CVAR increases with the increase of current velocity.When the BOP weight is insuffcient,obvious upbending is observed in the lower region and transition region,leading to local compression.When the platform moves in the opposite direction to the current,the maximum stress is larger than that of the scenario when the platform moves in the same direction as the current. 展开更多
关键词 compliant vertical access riser installation analysis dynamic performance variable length
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Comparison of Mortality, Length of Stay, and Hospitalization Costs of Hospitalized COVID-19 Patients with Cardiac and Non-Cardiac Disease
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作者 Babak Heidari Aghdam Zahra Kamali Seyedbaglou Amin Shams Akhtari 《Open Journal of Emergency Medicine》 2023年第3期57-67,共11页
Background: The COVID-19 pandemic has presented unprecedented challenges to global healthcare systems. As the pandemic unfolded, it became evident that certain groups of individuals were at an elevated risk of experie... Background: The COVID-19 pandemic has presented unprecedented challenges to global healthcare systems. As the pandemic unfolded, it became evident that certain groups of individuals were at an elevated risk of experiencing severe disease outcomes. Among these high-risk groups, individuals with pre-existing cardiac conditions emerged as particularly vulnerable. Objective: This study aimed to investigate the relationship between the length of stay, mortality, and costs of COVID-19 patients with and without a history of cardiac disease. Design: This retrospective study was conducted in Jam Hospital in Tehran, Iran, from March 21, 2021, to March 21, 2022. All patients with laboratory-confirmed COVID-19 who were hospitalized during this period were included. Results: A total of 500 COVID-19 patients were hospitalized, with 31.6% having a history of cardiac disease and 68.4% without any cardiac disease. Patients with cardiac disease were significantly older (median [range] age, 69.35 [37 - 94] years) compared to non-cardiac patients (54.95 [13 - 97] years) (p Conclusion: Patients with cardiac disease who are hospitalized with COVID-19 have a higher mortality rate, longer hospital stays, greater disease severity, ICU admission, and higher costs. Therefore, improved prevention and management strategies are crucial for these patients. 展开更多
关键词 COVID-19 Cardiac Disease length of Hospital Stay COSTS MORTALITY
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Concept Analysis: Emergency Department Crowding and Length of Stay before and after an Increase in Catchment Area
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作者 Ali M. Al Yasin 《Open Journal of Nursing》 2023年第8期500-511,共12页
Several notable issues arise from overcrowding in an emergency department (ED) for both patients and staff. Longer wait times, higher ambulance diversion rates, longer stays, higher incidence of medical errors, higher... Several notable issues arise from overcrowding in an emergency department (ED) for both patients and staff. Longer wait times, higher ambulance diversion rates, longer stays, higher incidence of medical errors, higher rates of patient mortality, and greater harm to hospitals due to financial losses are some of these problems. Collaboration is crucial in the healthcare industry since it determines the team’s hourly performance in managing patient care. By using Walker and Avant’s (2011) concept analysis method, the author reviewed the literature to better understand ED crowding, to ensure that patients receive safe treatment in a timely manner, and to highlight best practices that can be identified through concept analysis and practice evaluations. In conducting this concept analysis, Walker and Avant’s framework was applied to examine the nature of the findings selected for the advancement of the concept. Everyone working in the ED, from those who determine policy to those on the front lines continually encounter new obstacles, but has little or no time to formulate fresh concepts or reconsider how ED treatment is provided. Overcrowding occurs when the number of patients requiring attention, awaiting transfer, or undergoing diagnosis and treatment exceeds the physical capacity of ED staff. If a clear plan is not in place to increase and improve services in proportion to a growing population, this situation will persist. 展开更多
关键词 OVERCROWDING Increasing Population Emergency Room length of Stay Input THROUGHPUT Output
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Degree of style coiling is associated with corolla-tube length in the nectarless flowers of Roscoea schneideriana
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作者 Bo Wang Ze-Yu Tong +3 位作者 Ying-Ze Xiong Xiao-Fan Wang W.Scott Armbruster Shuang-Quan Huang 《Plant Diversity》 SCIE CAS CSCD 2023年第6期748-751,共4页
The plant-pollinator‘arms race’model posits that a major driver of the evolution of elongated corollas in flowers is reciprocal selection for‘morphological fit’between pollinator-tongue length and access distance ... The plant-pollinator‘arms race’model posits that a major driver of the evolution of elongated corollas in flowers is reciprocal selection for‘morphological fit’between pollinator-tongue length and access distance to nectar(usually corolla-tube length).Evidence for the pollinator-mediated selection on tube length and evolution of multiple,correlated floral traits remains inconclusive.To gain possible insights into the strength of stabilizing selection by assessing standing phenotypic variation,we measured a series of functionally important floral traits,including corolla tube length and‘effective’tube depth and degree of style coiling.We then calculated coefficients of variation(CV)for these traits in three field populations of R.schneideriana.Unlike in most long-tubed flowers,the bottom part of the corolla tube is completely occupied by the style,with no room for nectar.The length of this portion of the corolla tube was more variable(higher CV)than the upper part of the corolla tube,suggesting that functional tube depth was under stronger stabilizing selection.The degree of style coiling was negatively related to the corolla-tube length in all three populations of R.schneideriana,suggesting that there may be conflicting selection acting on style length and corolla-tube length,which are otherwise usually tightly correlated.Given the lack of nectar in the flowers of this species,the long corolla tubes and long styles may represent morphological holdovers from ancestors that were pollinated by long-tongued pollinators,as is still seen in related species in the western Himalayas. 展开更多
关键词 Coefficient of variation Coiled style Corolla-tube length Nectar depth Pollinator shift Trait covariation
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A Method of Integrating Length Constraints into Encoder-Decoder Transformer for Abstractive Text Summarization
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作者 Ngoc-Khuong Nguyen Dac-Nhuong Le +1 位作者 Viet-Ha Nguyen Anh-Cuong Le 《Intelligent Automation & Soft Computing》 2023年第10期1-18,共18页
Text summarization aims to generate a concise version of the original text.The longer the summary text is,themore detailed it will be fromthe original text,and this depends on the intended use.Therefore,the problem of... Text summarization aims to generate a concise version of the original text.The longer the summary text is,themore detailed it will be fromthe original text,and this depends on the intended use.Therefore,the problem of generating summary texts with desired lengths is a vital task to put the research into practice.To solve this problem,in this paper,we propose a new method to integrate the desired length of the summarized text into the encoder-decoder model for the abstractive text summarization problem.This length parameter is integrated into the encoding phase at each self-attention step and the decoding process by preserving the remaining length for calculating headattention in the generation process and using it as length embeddings added to theword embeddings.We conducted experiments for the proposed model on the two data sets,Cable News Network(CNN)Daily and NEWSROOM,with different desired output lengths.The obtained results show the proposed model’s effectiveness compared with related studies. 展开更多
关键词 length controllable abstractive text summarization length embedding
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经阴道超声E-cervix技术对中孕期妇女自发性早产的预测价值
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作者 吴瑶 朱剑芳 +1 位作者 肖菊花 韩小羽 《实用临床医学(江西)》 CAS 2024年第1期70-73,共4页
目的探讨应用经阴道超声宫颈弹性成像(E-Cervix)技术预测中孕期妇女自发性早产的价值。方法选取2022年1月至2023年3月在江西省妇幼保健院进行产检的225例孕产妇为研究对象。根据是否孕足月将其划分为早产组(n=105)和足月产组(n=120),回... 目的探讨应用经阴道超声宫颈弹性成像(E-Cervix)技术预测中孕期妇女自发性早产的价值。方法选取2022年1月至2023年3月在江西省妇幼保健院进行产检的225例孕产妇为研究对象。根据是否孕足月将其划分为早产组(n=105)和足月产组(n=120),回顾性分析2组临床资料和超声检查参数[宫颈长度(CL)、宫颈弹性成像]。运用多元逻辑回归分析影响自发性早产发生的相关因素,应用受试者工作特征曲线(ROC)评估妊娠中期CL及宫颈弹性值预测自发性早产的效能。结果双胎(Z=9.909,P=0.002)和宫颈机能不全(Z=14.189,P<0.001)是早产的危险因素。妊娠中期CL越短(t=2.312,P=0.022),硬度比值(t=6.189,P<0.001)越小,弹性对比指数(t=-3.002,P=0.003)、宫颈内口(t=-4.890,P<0.001)应变值、宫颈外口应变值(t=-5.787,P<0.001)越大,早产发生的风险越高。ROC分析结果显示,宫颈内口应变值(AUC=0.689)、宫颈外口应变值(AUC=0.612)、弹性对比指数(AUC=0.718),各指标联合诊断较单一指标具有更高的预测早产的价值(AUC=0.764)。结论应用E-Cervix技术能够有效地预测中孕期孕妇自发性早产的可能性。 展开更多
关键词 自发性早产 超声E-cervix技术 预测效能 中孕期
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Planck Scale Fluid Mechanics: Measuring the Planck Length from Fluid Mechanics Independent of G
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作者 Espen Gaarder Haug 《Open Journal of Fluid Dynamics》 2023年第S1期250-261,共12页
We demonstrate how to extract the Planck length from hydrostatic pressure without relying on any knowledge of Newton’s gravitational constant, G. By measuring the pressure from a water column, we can determine the Pl... We demonstrate how to extract the Planck length from hydrostatic pressure without relying on any knowledge of Newton’s gravitational constant, G. By measuring the pressure from a water column, we can determine the Planck length without requiring knowledge of either G or the Planck constant. This experiment is simple to perform and cost-effective, making it not only of interest to researchers studying gravity but also suitable for low-budget educational settings. Despite its simplicity, this has never been demonstrated to be possible before, and it is achievable due to new theoretical insights into gravity and its connection to quantum gravity and the Planck scale. This provides new insights into fluid mechanics and the Planck scale. We are also exploring initial concepts related to what we are calling “Planck fluid”, which could potentially play a central role in quantum gravity and quantum fluid mechanics. 展开更多
关键词 Planck length Hydrostatic Pressure Pascal’s Law GRAVITY Planck Fluid
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Hematopoietic stem cell transplantation of aplastic anemia by relative with mutations and normal telomere length: A case report
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作者 Jin Yan Ting Jin Li Wang 《World Journal of Clinical Cases》 SCIE 2023年第29期7200-7206,共7页
BACKGROUND Immunosuppressive therapy and matched sibling donor hematopoietic stem cell transplantation(MSD-HSCT)are the preferred treatments for aplastic anemia(AA).CASE SUMMARY In this report,we describe a 43-year-ol... BACKGROUND Immunosuppressive therapy and matched sibling donor hematopoietic stem cell transplantation(MSD-HSCT)are the preferred treatments for aplastic anemia(AA).CASE SUMMARY In this report,we describe a 43-year-old male patient with severe AA who carried BRIP1(also known as FANCJ),TINF2,and TCIRG1 mutations.Screening of the family pedigree revealed the same TINF2 mutation in his mother and older brother,with his older brother also carrying the BRIP1 variant and demonstrating normal telomere length and hematopoietic function.The patient was successfully treated with oral cyclosporine A,eltrombopag,and acetylcysteine,achieving remission 4 years after receiving MSD-HSCT from his older brother.CONCLUSION This case provides a valuable clinical reference for individuals with suspected pathogenic gene mutations,normal telomere length,and hematopoietic function,highlighting them as potential donors for patients with AA. 展开更多
关键词 Aplastic anemia Hematopoietic stem cell transplantation BRIP1 gene TINF2 gene Telomere length Case report
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Machine learning applications for the prediction of extended length of stay in geriatric hip fracture patients
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作者 Chu-Wei Tian Xiang-Xu Chen +4 位作者 Liu Shi Huan-Yi Zhu Guang-Chun Dai Hui Chen Yun-Feng Rui 《World Journal of Orthopedics》 2023年第10期741-754,共14页
BACKGROUND Geriatric hip fractures are one of the most common fractures in elderly individuals,and prolonged hospital stays increase the risk of death and complications.Machine learning(ML)has become prevalent in clin... BACKGROUND Geriatric hip fractures are one of the most common fractures in elderly individuals,and prolonged hospital stays increase the risk of death and complications.Machine learning(ML)has become prevalent in clinical data processing and predictive models.This study aims to develop ML models for predicting extended length of stay(eLOS)among geriatric patients with hip fractures and to identify the associated risk factors.AIM To develop ML models for predicting the eLOS among geriatric patients with hip fractures,identify associated risk factors,and compare the performance of each model.METHODS A retrospective study was conducted at a single orthopaedic trauma centre,enrolling all patients who underwent hip fracture surgery between January 2018 and December 2022.The study collected various patient characteristics,encompassing demographic data,general health status,injury-related data,laboratory examinations,surgery-related data,and length of stay.Features that exhibited significant differences in univariate analysis were integrated into the ML model establishment and subsequently cross-verified.The study compared the performance of the ML models and determined the risk factors for eLOS.RESULTS The study included 763 patients,with 380 experiencing eLOS.Among the models,the decision tree,random forest,and extreme Gradient Boosting models demonstrated the most robust performance.Notably,the artificial neural network model also exhibited impressive results.After cross-validation,the support vector machine and logistic regression models demonstrated superior performance.Predictors for eLOS included delayed surgery,D-dimer level,American Society of Anaesthesiologists(ASA)classification,type of surgery,and sex.CONCLUSION ML proved to be highly accurate in predicting the eLOS for geriatric patients with hip fractures.The identified key risk factors were delayed surgery,D-dimer level,ASA classification,type of surgery,and sex.This valuable information can aid clinicians in allocating resources more efficiently to meet patient demand effectively. 展开更多
关键词 Machine learning Extended length of stay Hip fracture Enhanced recovery after surgery Risk factors
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Health Vigilance and Risk Factors for Cervical Cancer: A Study in the State of Maranhão, Brazil
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作者 José Márcio Soares Leite Carlos Tomaz 《Open Journal of Epidemiology》 2024年第1期75-89,共15页
The purpose of this cross-sectional study was to investigate the importance of health vigilance in the prevention of cervical cancer. The sample consisted of 536 women. To identify which risk factors were associated w... The purpose of this cross-sectional study was to investigate the importance of health vigilance in the prevention of cervical cancer. The sample consisted of 536 women. To identify which risk factors were associated with cervical cancer or with an increase in the mortality rate of this kind of cancer, a logistic regression model was used. The Odds Ratios (OR) and their respective 95% confidence intervals were also calculated. Most of them were at the age of highest incidence of cervical cancer (21 - 59 years old), had an unstable conjugal situation, minimal educational level (78.7%), low income (58.3%), consumed alcoholic beverages (56.4%), had a history of smoking (57.0%) and possessed limited knowledge about the prevention. These results are discussed in terms of a predictive model for cervical cancer that considers the importance of public health vigilance in the screening and precocious diagnosis. 展开更多
关键词 CANCER cervix Uteri Public Health Surveillance EPIDEMIOLOGY
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