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Tumour response following preoperative chemotherapy is affected by body mass index in patients with colorectal liver metastases
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作者 Hua-Chuan Song Hang-Cheng Zhou +10 位作者 Ping Gu Bing Bao Quan Sun Tian-Ming Mei Wei Cui Kang Yao Huan-Zhang Yao Shen-Yu Zhang Yong-Shuai Wang Rui-Peng Song Ji-Zhou Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第2期331-342,共12页
BACKGROUND Colorectal cancer is the third most prevalent malignancy globally and ranks second in cancer-related mortality,with the liver being the primary organ of metastasis.Preoperative chemotherapy is widely recomm... BACKGROUND Colorectal cancer is the third most prevalent malignancy globally and ranks second in cancer-related mortality,with the liver being the primary organ of metastasis.Preoperative chemotherapy is widely recommended for initially or potentially resectable colorectal liver metastases(CRLMs).Tumour pathological response serves as the most important and intuitive indicator for assessing the efficacy of chemotherapy.However,the postoperative pathological results reveal that a considerable number of patients exhibit a poor response to preoperative chemotherapy.Body mass index(BMI)is one of the factors affecting the tumori-genesis and progression of colorectal cancer as well as prognosis after various antitumour therapies.Several studies have indicated that overweight and obese patients with metastatic colorectal cancer experience worse prognoses than those with normal weight,particularly when receiving first-line chemotherapy regimens in combination with bevacizumab.AIM To explore the predictive value of BMI regarding the pathologic response following preoperative chemotherapy for CRLMs.METHODS A retrospective analysis was performed in 126 consecutive patients with CRLM who underwent hepatectomy following preoperative chemotherapy at four different hospitals from October 2019 to July 2023.Univariate and multivariate logistic regression models were applied to analyse potential predictors of tumour pathological response.The Kaplan-Meier method with log rank test was used to compare progression-free survival(PFS)between patients with high and low BMI.BMI<24.0 kg/m^(2) was defined as low BMI,and tumour regression grade 1-2 was defined as complete tumour response.RESULTS Low BMI was observed in 74(58.7%)patients and complete tumour response was found in 27(21.4%)patients.The rate of complete tumour response was significantly higher in patients with low BMI(29.7%vs 9.6%,P=0.007).Multivariate analysis revealed that low BMI[odds ratio(OR)=4.56,95%confidence interval(CI):1.42-14.63,P=0.011],targeted therapy with bevacizumab(OR=3.02,95%CI:1.10-8.33,P=0.033),preoperative carcinoembryonic antigen level<10 ng/mL(OR=3.84,95%CI:1.19-12.44,P=0.025)and severe sinusoidal dilatation(OR=0.17,95%CI:0.03-0.90,P=0.037)were independent predictive factors for complete tumour response.The low BMI group exhibited a significantly longer median PFS than the high BMI group(10.7 mo vs 4.7 mo,P=0.011).CONCLUSION In CRLM patients receiving preoperative chemotherapy,a low BMI may be associated with better tumour response and longer PFS. 展开更多
关键词 Colorectal liver metastases body mass index Tumour regression grade Preoperative chemotherapy HEPATECTOMY
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Wings-FDY一步法生产ITY的工艺研究
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作者 周龙 余锡攀 +2 位作者 李振宇 孙建杰 杜杨洋 《聚酯工业》 CAS 2024年第3期26-28,共3页
通过设备改造及工艺优化,成功实现了ITY在Wings-FDY设备上一步法生产。研究结果表明:风压设定为30 Pa,调整纺丝/卷绕上油比例为6:4,预热辊温度51℃,定型辊温度124℃,拉伸倍数3.2,卷绕速度3550 m/min时,ITY 148dtex/108f纺况稳定,物理指... 通过设备改造及工艺优化,成功实现了ITY在Wings-FDY设备上一步法生产。研究结果表明:风压设定为30 Pa,调整纺丝/卷绕上油比例为6:4,预热辊温度51℃,定型辊温度124℃,拉伸倍数3.2,卷绕速度3550 m/min时,ITY 148dtex/108f纺况稳定,物理指标均匀,满足客户定制化的产品需求。 展开更多
关键词 ITY wings-FDY 设备改造
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WingsFDY设备生产22dtex/24f细旦涤纶的工艺探讨
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作者 翟佳羽 袁礼栋 +2 位作者 李婧楠 苏宏新 赵毛毛 《合成纤维》 CAS 2024年第8期18-22,共5页
对22dtex/24f细旦涤纶全拉伸丝(FDY)生产中的熔体输送工艺、纺丝工艺、冷却工艺和牵伸定形等工艺进行了详细的分析与探讨。生产实践表明,该产品生产中采用的巴马格8辊WingsFDY设备具有高效节能、流程短的优势,能够有效降低FDY的生产成本... 对22dtex/24f细旦涤纶全拉伸丝(FDY)生产中的熔体输送工艺、纺丝工艺、冷却工艺和牵伸定形等工艺进行了详细的分析与探讨。生产实践表明,该产品生产中采用的巴马格8辊WingsFDY设备具有高效节能、流程短的优势,能够有效降低FDY的生产成本,对设备应用及新品种的开发具有一定的实践指导意义。 展开更多
关键词 细旦涤纶DTY 巴马格wingsFDY设备 工艺
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交互式数字叙事:加拿大Writing New Body Worlds阅读治疗新探索
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作者 牟晓青 于志涛 《图书馆论坛》 北大核心 2024年第4期222-230,F0003,共10页
文章基于相关研究文献与语料,对加拿大WNB阅读治疗实践进行梳理与归纳。WNB首次使用交互式数字叙事技术,构建面向公众的阅读治疗平台,以其交互式特征,融合了阅读和治疗引导两个过程,提供可访问的非临床方式,可面向大规模人群实现预防性... 文章基于相关研究文献与语料,对加拿大WNB阅读治疗实践进行梳理与归纳。WNB首次使用交互式数字叙事技术,构建面向公众的阅读治疗平台,以其交互式特征,融合了阅读和治疗引导两个过程,提供可访问的非临床方式,可面向大规模人群实现预防性健康干预。基于数据与计算的精准化阅读治疗是数字人文视角下的新变革,更具推广应用价值;以在线阅读平台建设为依托,推进实施平台化的阅读和治疗应成为未来发展方向之一;基于阅读形态与体验因技术赋能而改变的现状,图书馆应发挥引领作用,积极收集、创建或协助创建数字故事,推进阅读推广、服务与治疗的融合性发展,成为社区建设促进者、历史欣赏者和社区参与倡导者,也使阅读借助交互式数字叙事这一新载体,更好地发挥变革的力量,促进健康与幸福。 展开更多
关键词 交互式数字叙事 阅读治疗 Writing New body Worlds 加拿大
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3D body解剖软件联合PACS系统在骨科临床实践教学中的应用
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作者 王建乐 徐文斌 +3 位作者 马彦 马建军 范顺武 沈舒滢 《全科医学临床与教育》 2024年第6期530-532,共3页
目的探讨3D body解剖软件结合医学影像存档与通信系统(PACS)在骨科临床实践教学中的应用效果。方法选择2023年1月至2023年12月在浙江大学医学院附属邵逸夫医院骨科轮转的60名实习生,按照随机数字表法分成实验组和对照组,每组30名。对照... 目的探讨3D body解剖软件结合医学影像存档与通信系统(PACS)在骨科临床实践教学中的应用效果。方法选择2023年1月至2023年12月在浙江大学医学院附属邵逸夫医院骨科轮转的60名实习生,按照随机数字表法分成实验组和对照组,每组30名。对照组采用传统线上结合线下的混合式教学方法,实验组采用3D body解剖软件联合PACS系统带教模式。在实习期结束时,对两组实习生进行闭卷理论考试与临床实践操作考核,并采用问卷调查方式评估实习生对课程的满意度。结果实验组实习生的理论考试与临床实践操作成绩均高于对照组,差异均有统计学意义(t分别=6.59、4.22,P均<0.05)。实验组实习生在学习兴趣、教学难度、专业能力以及医患沟通能力提升方面的满意度均高于对照组,差异均有统计学意义(χ^(2)分别=9.93、3.77、6.94、8.52,P均<0.05)。结论3D body解剖软件联合PACS系统带教模式运用到骨科实习生的临床教学中,能帮助实习生提高学习兴趣以及医患沟通能力,加强对骨科知识的掌握,降低知识的理解难度,对于提升临床医学教学质量具有重要意义。 展开更多
关键词 3D body解剖软件 PACS系统 骨科实践 临床教学
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Soft,body conformable electronics for thermoregulation enabled by kirigami 被引量:1
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作者 Lung Chow Guangyao Zhao +17 位作者 Pengcheng Wu Xingcan Huang Jiyu Li Jian Li Wanying Wang Guihuan Guo Zhiyuan Li Jiachen Wang Jingkun Zhou Yawen Yang Yuyu Gao Binbin Zhang Qiang Zhang Dengfeng Li Ya Huang Kuanming Yao Jian Lu Xinge Yu 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期453-462,共10页
The application of thermoelectric devices(TEDs)for personalized thermoregulation is attractive for saving energy while balancing the quality of life.TEDs that directly attach to human skin remarkably minimized the ene... The application of thermoelectric devices(TEDs)for personalized thermoregulation is attractive for saving energy while balancing the quality of life.TEDs that directly attach to human skin remarkably minimized the energy wasted for cooling the entire environment.However,facing the extreme dynamic geometry change and strain of human skin,conventional TEDs cannot align with the contour of our bodies for the best thermoregulation effect.Hence,we designed a kirigami-based wearable TED with excellent water vapor permeability,flexibility,and conformability.Numerical analysis and experimental results reveal that our product can withstand various types of large mechanical deformation without circuit rupture.The stated outcome and proposed facile approach not only reinforce the development of wearable TEDs but also offer an innovative opportunity for different electronics that require high conformability. 展开更多
关键词 THERMOREGULATION THERMOELECTRIC Kirigami body conformable WEARABLE
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Association of daily sitting time and leisure-time physical activity with body fat among U.S.adults 被引量:1
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作者 Jingwen Liao Min Hu +4 位作者 Kellie Imm Clifton J.Holmes Jie Zhu Chao Cao Lin Yang 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期195-203,共9页
Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investi... Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investigated the independent and joint associations of daily sitting time and physical activity with body fat among adults.Methods:This was a cross-sectional analysis of U.S.nationally representative data from the National Health and Nutrition Examination Survey2011-2018 among adults aged 20 years or older.Daily sitting time and leisure-time physical activity(LTPA)were self-reported using the Global Physical Activity Questionnaire.Body fat(total and trunk fat percentage)was determined via dual X-ray absorptiometry.Results:Among 10,808 adults,about 54.6%spent 6 h/day or more sitting;more than one-half reported no LTPA(inactive)or less than 150 min/week LTPA(insufficiently active)with only 43.3%reported 150 min/week or more LTPA(active)in the past week.After fully adjusting for sociodemographic data,lifestyle behaviors,and chronic conditions,prolonged sitting time and low levels of LTPA were associated with higher total and trunk fat percentages in both sexes.When stratifying by LTPA,the association between daily sitting time and body fat appeared to be stronger in those who were inactive/insuufficiently active.In the joint analyses,inactive/insuufficiently active adults who reported sitting more than 8 h/day had the highest total(female:3.99%(95%confidence interval(95%CI):3.09%-4.88%);male:3.79%(95%CI:2.75%-4.82%))and trunk body fat percentages(female:4.21%(95%CI:3.09%-5.32%);male:4.07%(95%CI:2.95%-5.19%))when compared with those who were active and sitting less than 4 h/day.Conclusion:Prolonged daily sitting time was associated with increased body fat among U.S.adults.The higher body fat associated with 6 h/day sitting may not be offset by achieving recommended levels of physical activity. 展开更多
关键词 ADULTS body fat distribution Physical activity Sitting time
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Stereotactic body radiotherapy in pancreatic adenocarcinoma 被引量:1
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作者 Carolina de la Pinta 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第1期14-19,共6页
Background:Stereotactic body radiotherapy(SBRT)in pancreatic cancer allows high delivery of radiation doses on tumors without affecting surrounding tissue.This review aimed at the SBRT application in the treatment of ... Background:Stereotactic body radiotherapy(SBRT)in pancreatic cancer allows high delivery of radiation doses on tumors without affecting surrounding tissue.This review aimed at the SBRT application in the treatment of pancreatic cancer.Data sources:We retrieved articles published in MEDLINE/PubMed from January 2017 to December 2022.Keywords used in the search included:“pancreatic adenocarcinoma”OR“pancreatic cancer”AND“stereotactic ablative radiotherapy(SABR)”OR“stereotactic body radiotherapy(SBRT)”OR“chemoradiotherapy(CRT)”.English language articles with information on technical characteristics,doses and fractionation,indications,recurrence patterns,local control and toxicities of SBRT in pancreatic tumors were included.All articles were assessed for validity and relevant content.Results:Optimal doses and fractionation have not yet been defined.However,SBRT could be the standard treatment in patients with pancreatic adenocarcinoma in addition to CRT.Furthermore,the combination of SBRT with chemotherapy may have additive or synergic effect on pancreatic adenocarcinoma.Conclusions:SBRT is an effective modality for patients with pancreatic cancer,supported by clinical practice guidelines as it has demonstrated good tolerance and good disease control.SBRT opens a possibility of improving outcomes for these patients,both in neoadjuvant treatment and with radical intent. 展开更多
关键词 CHEMORADIOTHERAPY Pancreatic adenocarcinoma RADIOTHERAPY Stereotactic body radiotherapy Stereotactic ablative radiotherapy
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Body composition and metabolic syndrome in patients with type 1 diabetes 被引量:2
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作者 Qiong Zeng Xiao-Jing Chen +3 位作者 Yi-Ting He Ze-Ming Ma Yi-Xi Wu Kun Lin 《World Journal of Diabetes》 SCIE 2024年第1期81-91,共11页
BACKGROUND In recent years,the prevalence of obesity and metabolic syndrome in type 1 diabetes(T1DM)patients has gradually increased.Insulin resistance in T1DM deserves attention.It is necessary to clarify the relatio... BACKGROUND In recent years,the prevalence of obesity and metabolic syndrome in type 1 diabetes(T1DM)patients has gradually increased.Insulin resistance in T1DM deserves attention.It is necessary to clarify the relationship between body composition,metabolic syndrome and insulin resistance in T1DM to guide clinical treatment and intervention.AIM To assess body composition(BC)in T1DM patients and evaluate the relationship between BC,metabolic syndrome(MS),and insulin resistance in these indi-viduals.METHODS A total of 101 subjects with T1DM,aged 10 years or older,and with a disease duration of over 1 year were included.Bioelectrical impedance analysis using the Tsinghua-Tongfang BC Analyzer BCA-1B was employed to measure various BC parameters.Clinical and laboratory data were collected,and insulin resistance was calculated using the estimated glucose disposal rate(eGDR).RESULTS MS was diagnosed in 16/101 patients(15.84%),overweight in 16/101 patients(15.84%),obesity in 4/101(3.96%),hypertension in 34/101(33.66%%)and dyslip-idemia in 16/101 patients(15.84%).Visceral fat index(VFI)and trunk fat mass were significantly and negatively correlated with eGDR(both P<0.001).Female patients exhibited higher body fat percentage and visceral fat ratio compared to male patients.Binary logistic regression analysis revealed that significant factors for MS included eGDR[P=0.017,odds ratio(OR)=0.109],VFI(P=0.030,OR=3.529),and a family history of diabetes(P=0.004,OR=0.228).Significant factors for hypertension included eGDR(P<0.001,OR=0.488)and skeletal muscle mass(P=0.003,OR=1.111).Significant factors for dyslipidemia included trunk fat mass(P=0.033,OR=1.202)and eGDR(P=0.037,OR=0.708).CONCLUSION Visceral fat was found to be a superior predictor of MS compared to conventional measures such as body mass index and waist-to-hip ratio in Chinese individuals with T1DM.BC analysis,specifically identifying visceral fat(trunk fat),may play an important role in identifying the increased risk of MS in non-obese patients with T1DM. 展开更多
关键词 body composition Metabolic syndrome Insulin resistance Visceral fat Estimated glucose disposal rate
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Wings-plus设备生产全消光FDY工艺探讨 被引量:1
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作者 冯斌 朱昌波 +3 位作者 褚冬生 郑伟 唐晓凯 崔利 《聚酯工业》 CAS 2023年第4期45-47,共3页
在大容量聚酯熔体直纺生产线上进行设备技术改造,在熔体输送管道上通过在线添加注射设备将全消光母粒注射进入熔体,并在动态混合器中混合均匀,得到全消光聚酯熔体,采用巴马格的Wings-plus FDY生产设备的一步拉伸工艺生产全消光FDY纤维... 在大容量聚酯熔体直纺生产线上进行设备技术改造,在熔体输送管道上通过在线添加注射设备将全消光母粒注射进入熔体,并在动态混合器中混合均匀,得到全消光聚酯熔体,采用巴马格的Wings-plus FDY生产设备的一步拉伸工艺生产全消光FDY纤维。该方法成本投入小,得到的全消光纤维物理指标可以满足中高端客户需求。 展开更多
关键词 全消光FDY wings-plus设备 生产技术改造
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3D Body解剖软件结合CBL教学法在骨科实习生临床带教中的应用
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作者 张树文 地力木拉提·艾克热木 王浩 《教育进展》 2024年第6期1489-1493,共5页
目的:探讨3D body解剖软件结合CBL教学法在骨科实习生临床带教中的应用效果。方法:随机选取2022年1月~2023年12月在我科室实习的36名骨科实习生为研究对象,随机分为观察组和对照组,对照组采用CBL教学模式,观察组在对照组的教学模式上运... 目的:探讨3D body解剖软件结合CBL教学法在骨科实习生临床带教中的应用效果。方法:随机选取2022年1月~2023年12月在我科室实习的36名骨科实习生为研究对象,随机分为观察组和对照组,对照组采用CBL教学模式,观察组在对照组的教学模式上运用3D body解剖软件。教学结束后,比较两组学生的理论知识考试成绩,PPT汇报成绩以及教学满意度。结果:观察组学生理论知识考核成绩、PPT汇报成绩、教学满意度明显高于对照组,差异具有显著性(P < 0.05)。结论:3D body解剖软件结合CBL教学法应用于骨科实习生临床带教,可以有效提高学生成绩,调动学生积极性及自主学习能力,提升教学满意度。 展开更多
关键词 3D body解剖软件 CBL教学法 实习生 骨科
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Development and formation of wing cuticle based on transcriptomic analysis in Locusta migratoria during metamorphosis
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作者 Jing Zhang Zhaochen Wu +5 位作者 Shuo Li He Huang Suning Liu Weimin Liu Xiaoming Zhao Jianzhen Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1285-1299,共15页
Wings are an important flight organ of insects.Wing development is a complex process controlled by a series of genes.The flightless wing pad transforms into a mature wing with the function of migratory flight during t... Wings are an important flight organ of insects.Wing development is a complex process controlled by a series of genes.The flightless wing pad transforms into a mature wing with the function of migratory flight during the nymphto-adult metamorphosis.However,the mechanism of wing morphogenesis in locusts is still unclear.This study analyzed the microstructures of the locust wing pads at pre-eclosion and the wings after eclosion and performed the comparative transcriptome analysis.RNA-seq identified 25,334 unigenesand 3,430 differentially expressed genes(DEGs)(1,907 up-regulated and 1,523 down-regulated).The DEGs mainly included cuticle development(LmACPs),chitin metabolism(Lm Idgf4),lipid metabolism-related genes,cell adhesion(Integrin),zinc finger transcription factors(LmSalm,LmZF593 andLmZF521),and others.Functional analysis based on RNA interference and hematoxylin and eosin(H&E)staining showed that the three genes encoded zinc finger transcription factors are essential for forming wing cuticle and maintaining morphology in Locusta migratoria.Finally,the study found that the LmSalm regulates the expression of LmACPs in the wing pads at pre-eclosion,and LmZF593 and LmZF521 regulate the expression of LmIntegrin/LmIdgf4/LmHMT420 in the wings after eclosion.This study revealed that the molecular regulatory axis controls wing morphology in nymphal and adult stages of locusts,offering a theoretical basis for the study of wing development mechanisms in hemimetabolous insects. 展开更多
关键词 Locusta migratoria wing development METAMORPHOSIS RNA-SEQ
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0.05 T MRI for whole body
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作者 Ya Wang Shihao Tang +3 位作者 Jinyu Yang Bowen Peng Yajie Xu Xiaodong Yang 《Magnetic Resonance Letters》 2024年第3期60-61,共2页
Recently,a study on a 0.05 T,low-cost,low-power,and computing-driven shielding-free ultra-low-field(ULF)magnetic resonance imaging(MRI)scannerwas published.This work enhances the image quality of MRI and reduces the s... Recently,a study on a 0.05 T,low-cost,low-power,and computing-driven shielding-free ultra-low-field(ULF)magnetic resonance imaging(MRI)scannerwas published.This work enhances the image quality of MRI and reduces the scanning time based on deep learning methods,which is of great significance to enhancing the popularization and availability of MRI[1](https://www.science.org/doi/abs/10.1126/science.adm7168). 展开更多
关键词 SCANNER body SHIELDING
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Longitudinal changes in body weight of breastfeeding mothers in the first year after delivery and its relationship with human milk composition:a combined longitudinal and cross-sectional cohort study
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作者 Huijuan Ruan Yajie Zhang +6 位作者 Qingya Tang Xuan Zhao Xuelin Zhao Yi Xiang Wei Geng Yi Feng Wei Cai 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期254-264,共11页
Objective:Postpartum weight retention(PPWR)is a common problem among women after childbirth.The main objectives of this study are to understand the changes in body weight of breastfeeding mothers during long-term foll... Objective:Postpartum weight retention(PPWR)is a common problem among women after childbirth.The main objectives of this study are to understand the changes in body weight of breastfeeding mothers during long-term follow-up and preliminarily explore the relationship between maternal body weight and human milk composition,including macronutrients,leptin,and adiponectin.Methods:The study included a longitudinal cohort(122 mothers),and a cross-sectional cohort(37 mothers).The human milk,maternal weight,and dietary surveys were collected in the longitudinal cohort at different follow-up time points(1-14 days postpartum,2-4 months postpartum,5-7 months postpartum,and 12-17 months postpartum).The maternal body weight was analyzed using the responses in the survey questionnaires.A milk analyzer based on the mid-infrared spectroscopy(MIRS)was used to determine milk composition,and nutrition analysis software evaluated dietary intakes.In the cross-sectional cohort,participating mothers were asked to provide blood and human milk samples and pertinent information related to maternal body composition.Maternal body composition was measured by bioelectrical impedance analysis(BIA),while ELISA analyzed leptin and adiponectin in milk and serum.Results:At 5-7 months postpartum,the PPWR of breastfeeding mothers was(2.46±3.59)kg.At 12-17 months postpartum,the PPWR was(0.98±4.06)kg.PPWR was found to be negatively correlated with milk fat content within 14 days postpartum and positively correlated at 2-4 months postpartum.In addition,the maternal weight and body muscle mass were positively correlated with leptin and adiponectin in milk.Plasma leptin was positively correlated with the mother’s body weight,body mass index(BMI),FAT percentage,and body fat mass,while plasma adiponectin did not correlate with any parameter.The results also indicate that the PPWR did not correlate with leptin and adiponectin in plasma or milk.Conclusions:Breastfeeding mothers may retain considerable weight gain one year after delivery.Human milk composition may be related to changes in maternal body weight.Leptin and adiponectin in breast milk and leptin in plasma are associated with the maternal body composition.This study supports the notion that maternal nutritional status may affect offspring health through lactation,and future research should focus on exploring weight management of postpartum mothers. 展开更多
关键词 Human milk Milk composition body weight body mass index(BMI) Weight gain Postpartum weight retention
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Numerical Investigations on Dynamic Stall Characteristics of a Finite Wing
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作者 JING Simeng CAO Chenkai +2 位作者 GAO Yuan ZHAO Qijun ZHAO Guoqing 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第4期444-457,共14页
The paper examines the dynamic stall characteristics of a finite wing with an aspect ratio of eight in order to explore the 3D effects on flow topology,aerodynamic characteristics,and pitching damping.Firstly,CFD meth... The paper examines the dynamic stall characteristics of a finite wing with an aspect ratio of eight in order to explore the 3D effects on flow topology,aerodynamic characteristics,and pitching damping.Firstly,CFD methods are developed to calculate the aerodynamic characteristics of wings.The URANS equations are solved using a finite volume method,and the two-equation k-ωshear stress transport(SST)turbulence model is employed to account for viscosity effects.Secondly,the CFD methods are used to simulate the aerodynamic characteristics of both a static,rectangular wing and a pitching,tapered wing to verify their effectiveness and accuracy.The numerical results show good agreement with experimental data.Subsequently,the static and dynamic characteristics of the finite wing are computed and discussed.The results reveal significant 3D flow structures during both static and dynamic stalls,including wing tip vortices,arch vortices,Ω-type vortices,and ring vortices.These phenomena lead to differences in the aerodynamic characteristics of the finite wing compared with a 2D airfoil.Specifically,the finite wing has a smaller lift slope during attached-flow stages,higher stall angles,and more gradual stall behavior.Flow separation initially occurs in the middle spanwise section and gradually spreads to both ends.Regarding aerodynamic damping,the inboard sections mainly generate unstable loading.Furthermore,sections experiencing light stall have a higher tendency to produce negative damping compared with sections experiencing deep dynamic stall. 展开更多
关键词 finite wing dynamic stall aerodynamic damping 3D effects
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The Impact of Social Media on Dietary Behaviors and Body Image of College Students: A Qualitative Approach
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作者 Basem Azmy Saad Boutros Tabbetha D. Lopez Valencia Browning-Keen 《Food and Nutrition Sciences》 CAS 2024年第8期711-726,共16页
Background: The use of social media platforms for health and nutrition information has become popular among college students. Although social media made information readily accessible in different formats, nutritional... Background: The use of social media platforms for health and nutrition information has become popular among college students. Although social media made information readily accessible in different formats, nutritional misinformation promoted by influencers and non-experts caused negative impact on diet behavior and perception of body image. Previous research indicated that extensive use of social media was positively linked to disordered eating behaviors. Social media platforms like Facebook and Instagram that allow users to follow celebrities intensified exposure to influencers’ messages and images and resulted in negative moods and body dissatisfaction. Objective: This paper aims to explore the impact of social media on college students’ dietary behaviors and body image. Participants: 18 undergraduate students from a public university in the Southern United States were recruited through a mass email. Methods: A cross-sectional qualitative study of three focus groups was conducted. The focus groups were based on guiding open-ended questions. Atlas.ti was used to code and analyze the data using inductive and deductive codes. Results: Three main themes were identified. The conditions theme included elements that explain why and how social media influences the participants’ actions. The actions theme included eating behavior, physical activity, and dietary supplement intake. The consequences theme describes anticipated or actual outcomes of actions such as body image and ideal weight. Conclusions: Social media has had a negative influence on diet behaviors and a positive influence on physical activity. Evidence-based nutrition and weight management information is needed to thwart potential misinformation. 展开更多
关键词 Social Media Nutrition Information Dietary Behavior body Image College Students
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Growth Performance of Crocodile Fed with Chicken Intestine and Trash Fish at Smallholder Farm in Siem Reap Province,Cambodia
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作者 Sourloing Hor Kanan Dim +3 位作者 Sungchang Kang Kroesna Kang Kouch Theng Manay Ith 《Journal of Environmental Science and Engineering(B)》 CAS 2024年第2期86-91,共6页
The experiment was conducted at the smallholder crocodile farm at Pouk district,Siem reap province,and lasted 12 months,commenced from January 1st to December 31st,2023.The CRBD(Completely Randomized Block Design),was... The experiment was conducted at the smallholder crocodile farm at Pouk district,Siem reap province,and lasted 12 months,commenced from January 1st to December 31st,2023.The CRBD(Completely Randomized Block Design),was used in 3 treatments,such as T1(fed chicken intestine only),T2(fed chicken intestine+trash fish)and T3(fed trash fish only),with 4 replications in each treatment.The block was set by gender of crocodile,male and female.The 36 of local breed crocodiles 4 months old were allocated into each replication randomly.The result found that the length of crocodile gradually increased in the first semester,then it greatly increased from or for second semester for all treatments.In addition,the final body length of crocodile was significant different among treatments(p<0.001),the treatment of T2(fed chicken intestine+trash fish)had the longest one.Body length was also affected by gender,and male crocodile had longer body length(p<0.001).However,there were no significant differences for the interaction between types of feed with gender(p>0.05)(Table 1).The body weight of crocodile had gradually increased in the first semester,then it greatly increased from or for second semester for all treatments,while the final body weight of crocodile was also significant different among treatments(p<0.001)and the gender of crocodile(p<0.001).The average ADG(Daily Weight Gain)was significant different among treatments(p<0.001).Treatment of T2(fed chicken intestine+trash fish)had highest ADG,11.05 g,followed by T3(fed trash fish only),while the T1 had the lowest one.The gender of crocodile affected the ADG of crocodile,and male crocodile had higher ADG than female crocodile(p<0.001).However,there were no significant differences for the interaction between type of feed with gender(p>0.05).Feed intake was calculated based on amount of feed offer and measured in fresh basis.The amount of intake feed in all treatments was the same.FCR(Feed Conversion Ratio)was significant different among treatments(p<0.001)and also gender of crocodile(p<0.001).However,there were no significant differences for the interaction between types of feed with gender(p>0.05).In conclusion,the uses of trash fish and chicken intestine are an alternative feed source for crocodile to result in higher growth performance of crocodile. 展开更多
关键词 Local breed body length body weight ADG FCR
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Energy Harvesting in the Wake of An Inverted C-Shaped Bluff Body
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作者 WANG Jun-lei LI Shen-fang +2 位作者 Md.Mahbub ALAM ZHU Hong-jun HU Guo-biao 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期68-80,共13页
This paper proposes a novel wake-induced vibration(WIV)-based energy harvesting system consisting of two bluff bodies.An inverted C-shaped bluff body is stationary installed at the upstream position to generate an int... This paper proposes a novel wake-induced vibration(WIV)-based energy harvesting system consisting of two bluff bodies.An inverted C-shaped bluff body is stationary installed at the upstream position to generate an interference wake street,and a cylinder bluff body equipped with a transducer is elastically suspended at the downstream position to harness WIV energy.The hydrodynamics and energy harvesting(EH)performance of the proposed system are investigated via experimental studies.The reduced velocity(U*)ranging from 2 to 14(the corresponding Reynolds number ranging from 15100 to 106200)is considered in the present study.It is found that the wake generated by the inverted C-shaped bluff body significantly affects the EH performance.Enlarging the opening angle(α)of the C-shaped bluff body increases the vibration amplitude of the downstream cylinder,thereby increasing the harvested power.When the spacing(L)between two bluff bodies is two times the cylinder diameter(D),the wake-induced vibration(WIV)mode is observed,while the combined WIV and wake galloping(WG)mode occurs whenαis 150°,and L equals 3D or 4D.The average drag coefficient becomes negative when L is 2D,3D,or 4D.By carefully configuring a C-shaped bluff body,the wake generated by it can bring an augmenting effect on the vibration of the downstream EH cylinder.For example,the RMS power output of the proposed EH system reaches a maximum of 0.31 W at U*=8 and L=4D,which is 300%greater than that of its traditional counterpart.Furthermore,after a number of case stud-ies,it is identified that the proposed EH system can achieve the best performance whenαis 150°and L=2D. 展开更多
关键词 wake-induced vibration vortex-induced vibration GALLOPING energy harvesting bluff body
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An adaptive machine learning-based optimization method in the aerodynamic analysis of a finite wing under various cruise conditions
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作者 Zilan Zhang Yu Ao +1 位作者 Shaofan Li Grace X.Gu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第1期27-34,共8页
Conventional wing aerodynamic optimization processes can be time-consuming and imprecise due to the complexity of versatile flight missions.Plenty of existing literature has considered two-dimensional infinite airfoil... Conventional wing aerodynamic optimization processes can be time-consuming and imprecise due to the complexity of versatile flight missions.Plenty of existing literature has considered two-dimensional infinite airfoil optimization,while three-dimensional finite wing optimizations are subject to limited study because of high computational costs.Here we create an adaptive optimization methodology built upon digitized wing shape deformation and deep learning algorithms,which enable the rapid formulation of finite wing designs for specific aerodynamic performance demands under different cruise conditions.This methodology unfolds in three stages:radial basis function interpolated wing generation,collection of inputs from computational fluid dynamics simulations,and deep neural network that constructs the surrogate model for the optimal wing configuration.It has been demonstrated that the proposed methodology can significantly reduce the computational cost of numerical simulations.It also has the potential to optimize various aerial vehicles undergoing different mission environments,loading conditions,and safety requirements. 展开更多
关键词 Aerodynamic optimization Computational fluid dynamics Radial basis function Finite wing Deep learning neural network
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Ecological Remediation Technology of Urban Landscape Water Body
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作者 SUN Xiangxuan XIONG Qingqing XIAO Shizhen 《Journal of Landscape Research》 2024年第1期55-58,共4页
Urban landscape water body is not only an important part of urban landscape construction,but also an important way to maintain landscape diversity and biodiversity,carrying the beautiful yearning of urban residents fo... Urban landscape water body is not only an important part of urban landscape construction,but also an important way to maintain landscape diversity and biodiversity,carrying the beautiful yearning of urban residents for natural life.A good state of urban landscape water body is crucial to the ecological environment of the city.However,due to the poor kinetic energy of urban landscape water body and the influence of various human factors,the quality of urban landscape water body often declines,and urban population is threatened by water security problems.Through the study of several water body ecological remediation technologies,relevant suggestions are put forward,in order to provide a reference for water pollution restoration and treatment in urban human settlement environment. 展开更多
关键词 Urban landscape water body Water body treatment Ecological remediation
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