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纳米纤维素抗菌复合材料的研究进展
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作者 孙波 何志斌 倪永浩 《中国造纸》 北大核心 2026年第2期176-188,共13页
纳米纤维素作为一种来源于木质纤维且具有纳米尺寸的纤维素衍生物或降解产物,因其优异的生物相容性、丰富的极性羟基、出色的力学性能和高比表面积,成为近年来备受关注的绿色载体材料。将纳米纤维素用于负载抗菌剂,制得纳米纤维素抗菌... 纳米纤维素作为一种来源于木质纤维且具有纳米尺寸的纤维素衍生物或降解产物,因其优异的生物相容性、丰富的极性羟基、出色的力学性能和高比表面积,成为近年来备受关注的绿色载体材料。将纳米纤维素用于负载抗菌剂,制得纳米纤维素抗菌复合材料,可广泛应用在食品行业、日用化工、医用敷料和水处理等领域。本文系统综述了纳米纤维素的结构特征及其改性手段,并重点探讨了其负载的各类抗菌剂(包括金属离子/金属氧化物类、微生物抗生素类、化学合成类及天然提取物类)。在此基础上,进一步总结了纳米纤维素抗菌复合材料在食品与日化用品行业的典型应用及市场化进展。最后,提出了该领域当前面临的主要挑战和机遇,对纳米纤维素抗菌复合材料的未来发展趋势进行了展望。 展开更多
关键词 纳米纤维素 抗菌剂 负载机制 抗菌复合材料
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Are emerging electroconductive biomaterials for spinal cord injury repair the future?
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作者 Aleksandra Serafin Maurice N.Collins 《Neural Regeneration Research》 2026年第3期1140-1141,共2页
Spinal cord injury(SCI)is a debilitating ailment that leads to the loss of motor and sensory functions,often leaving the patient paralyzed below the injury site(Chen et al.,2013).Globally around 250,000-300,000 people... Spinal cord injury(SCI)is a debilitating ailment that leads to the loss of motor and sensory functions,often leaving the patient paralyzed below the injury site(Chen et al.,2013).Globally around 250,000-300,000 people are diagnosed with SCI annually(Singh et al.,2014),and while this number appears quite low,the effect that an SCI has on the patient’s quality of life is drastic,due to the current difficulties to comprehensively treat this illness.The cost of patient care can also be quite costly,amounting to an estimated$1.69 billion in healthcare costs in the USA alone(Mahabaleshwarkar and Khanna,2014). 展开更多
关键词 spinal cord injury PARALYSIS electroconductive biomaterials healthcare costs sensory functions motor functions repair spinal cord injury sci
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Short bouts of accumulated exercise:Review and consensus statement on definition,efficacy,feasibility,practical applications,and future directions 被引量:1
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作者 Mingyue Yin Yongming Li +43 位作者 Abdul Rashid Aziz Aidan Buffey David J.Bishop Dapeng Bao George P.Nassis Hashim Islam Hongying Wang Jackson J.Fyfe Jianfang Xu Jianxiu Liu Jiexiu Zhao Jingwei Cao Jonathan P.Little Junqiang Qiu Keith M.Diaz Lijuan Wang Liye Zou Max J.Western Meynard L.Toledo Min Hu Minghui Quan Neville Owen Niels B.J.Vollaard Olivier Girard Qingde Shi Richard S.Metcalfe Rodrigo Ramirez-Campillo Ru Wang Waris Wongpipit Weimo Zhu Wenfei Zhu Weigang Xu Xiaochun Wang Xiaoping Chen Xiong Wang Xu Wen Yang Liu Ying Gao Yue Fu Zhaowei Kong Zhenbo Cao Zhengzhen Wang Peijie Chen Lijuan Mao 《Journal of Sport and Health Science》 2026年第2期1-30,共30页
Background:Insufficient physical activity and prolonged sedentary behavior have emerged as major global public health challenges.Short bouts(≤10 min)of accumulated exercise(SBAE)throughout the day may be a promising ... Background:Insufficient physical activity and prolonged sedentary behavior have emerged as major global public health challenges.Short bouts(≤10 min)of accumulated exercise(SBAE)throughout the day may be a promising strategy to mitigate the adverse effects of prolonged sitting and promote physical activity,ultimately promoting overall health.However,previous ambiguity in defining this concept has resulted in a fragmented and inconsistent evidence base,impeding practical applications,the development of guidelines,and policymaking.The purpose of this study is to establish an operational definition of SBAE by synthesizing systematic reviews and research trials alongside an expert consensus.Additionally,it seeks to evaluate acute and long-term efficacy and feasibility,providing evidence-based recommendations for practice and future research directions.Methods:A literature search was performed across PubMed and Web of Science,followed by systematic screening and summarization of eligible studies based on predefined inclusion criteria.Inclusion criteria encompassed various modes/types of SBAE(bouts lasting≤10 min,performed multiple times daily with≥30 min intervals);both aerobic and resistance exercise were considered.Relevant systematic reviews and research trials were included.Methodological quality,risk of bias,and evidence certainty were assessed.Expert consensus was obtained through a survey to evaluate recommendations and agreement levels on findings.Results:After analyzing 27 systematic reviews,135 research studies,and an expert consensus involving 48 researchers from 11 countries,SBAE is defined as any exercise mode of activity,regardless of intensity,that is accumulated in either continuous or intermittent bouts lasting≤10 min per session(including multiple intermittent sets)that are performed multiple times(≥2 sessions/day)per day,with intervals of≥30 min between bouts or otherwise sufficient time for recovery.When used to interrupt prolonged periods of sedentary time,SBAE mitigates the acute adverse effects of sedentary behavior on more than 10 clinical biomarkers of endocrine,cardiovascular,and brain health/function among adults of diverse ages and conditions.Moreover,SBAE was superior for improving acute glycemic control compared to a single continuous exercise session.As a long-term intervention(average of 11 weeks),SBAE can improve over 20 health outcomes,including peak oxygen uptake,resting blood pressure,and metabolic health.Additionally,SBAE might be more effective than continuous exercise for improving longer-term glycemic control and body composition.Long-term completion rates for SBAE interventions are generally high(95%),with low dropout rates(12%)and high adherence rates even without supervision(85%),and its safety has been preliminarily validated.Conclusion:An operational definition of SBAE is provided along with its classification and acute and long-term efficacy.Practical exercise prescription recommendations and evidence-based strategies for various populations and contexts are provided.Future research should focus on generating high-quality evidence for SBAE in 5 key areas:quantification and monitoring,population-specific responses,optimization of exercise prescriptions,intervention efficacy,and practical implementation.Additionally,addressing policy,environmental,and promotional barriers is crucial for transitioning from expert consensus to public consensus,and for facilitating the application of this strategy in real-world environments. 展开更多
关键词 Short bouts of accumulated exercise Exercise snacks Consensus statement Sedentary breaks
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Ultrasound-Guided Hydro Dissection: A Novel Treatment Approach for Intersection Syndrome
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作者 Yvonne Maura Murphy Dominic Frances O’Shea +1 位作者 Maura Gerardine O’Dea Dominic Colman Harmon 《Pain Studies and Treatment》 2025年第1期8-13,共6页
Background: Wrist pain is prevalent. Activities such as dexterous sports, prolonged use of personal handheld devices, and extensive desktop keyboard usage are common contributors to wrist pain. Intersection syndrome, ... Background: Wrist pain is prevalent. Activities such as dexterous sports, prolonged use of personal handheld devices, and extensive desktop keyboard usage are common contributors to wrist pain. Intersection syndrome, a form of inflammatory tenosynovitis, occurs at the intersection of the first and second dorsal compartments of the wrist. The first dorsal compartment is comprised of the tendons of abductor pollicis longus and extensor pollicis brevis, while the second dorsal compartment contains the tendons of extensor carpi radialis longus and extensor carpi radialis brevis. Intersection syndrome is diagnosed by pain localized to the dorsoradial forearm, approximately five cm proximal to the wrist joint, which worsens with resisted wrist and thumb extension. To date, the use of hydro dissection with 5% dextrose under ultrasound guidance as a treatment for Intersection syndrome has not been reported. This case report presents the first report on ultrasound-guided hydro dissection as a therapeutic approach for intersection syndrome. Methods: A case report, with informed consent, involving a 32-year-old male athlete. The patient, a hurling player, presented with chronic right wrist pain diagnosed as intersection syndrome. The condition significantly affected his work, sporting activities, and daily living activities. Previous conservative management and physiotherapy had failed to alleviate his symptoms. To confirm the diagnosis, relevant imaging was performed, supplemented by dynamic ultrasound assessment. The procedure was performed aseptically. Continuous ultrasound guidance was employed to ensure accurate needle placement. Once the needle tip position was confirmed, an initial injection of 5 mL of 0.25% chirocaine was administered. 10 mL of 5% dextrose was injected under ultrasound guidance for hydro dissection, with good visualization of the solution’s distribution. Conclusion: Ultrasound-guided hydro dissection has not previously been documented as a treatment option for intersection syndrome. In this case, it proved to be an effective pain-relieving therapy with sustained effect at three-month clinical follow-up. Further studies are required. 展开更多
关键词 Wrist Pain Intersection Syndrome Sports Injury Hydro Dissection ULTRASOUND
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Improving gastrointestinal scoring systems for predicting short-term mortality in critically ill patients
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作者 Shane Moore Noel E Donlon 《World Journal of Gastroenterology》 2025年第5期137-139,共3页
Shen et al’s retrospective study aims to compare the utility of two separate scoring systems for predicting mortality attributable to gastrointestinal(GI)injury in critically ill patients[the GI Dysfunction Score(GID... Shen et al’s retrospective study aims to compare the utility of two separate scoring systems for predicting mortality attributable to gastrointestinal(GI)injury in critically ill patients[the GI Dysfunction Score(GIDS)and the Acute Gastroin-testinal Injury(AGI)grade].The authors note that this study is the first proposal that suggests an equivalence between the ability of both scores to predict mor-tality at 28 days from intensive care unit(ICU)admission.Shen et al retrospec-tively analysed an ICU cohort of patients utilising two physicians administering both the AGI grade and GIDS score,using electronic healthcare records and ICU flowsheets.Where these physicians disagreed about the scores,the final decision as to the scores was made by an associate chief physician,or chief physician.We note that the primary reason for the development of GIDS was to create a clear score for GI dysfunction,with minimal subjectivity or inter-operator variability.The subjectivity inherent to the older AGI grading system is what ultimately led to the development of GIDS in 2021.By ensuring consensus between physicians administering the AGI,Shen et al have controlled for one of this grading systems biggest issues.We have concerns,however,that this does not represent the real-world challenges associated with applying the AGI compared to the newer GIDS,and wonder if this arbitration process had not been instituted,would the two scoring systems remain equivalent in terms of predicted mortality? 展开更多
关键词 Gastrointestinal injury Critical care Patient mortality prediction Gastrointe-stinal Dysfunction Score Acute Gastrointestinal Injury grade Intensive care unit scoring systems
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Engineered Lysozyme:An Eco-Friendly Bio-Mechanical Energy Harvester
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作者 Krittish Roy Zinnia Mallick +8 位作者 Charlie O’Mahony Laura Coffey Hema Dinesh Barnana Sarah Markham Utsa Sarkar Tewfik Solumane Ehtsham Ul Haque Dipankar Mandal Syed A.M.Tofail 《Energy & Environmental Materials》 2025年第1期113-120,共8页
Eco-friendly and antimicrobial globular protein lysozyme is widely produced for several commercial applications.Interestingly,it can also be able to convert mechanical and thermal energy into electricity due to its pi... Eco-friendly and antimicrobial globular protein lysozyme is widely produced for several commercial applications.Interestingly,it can also be able to convert mechanical and thermal energy into electricity due to its piezo-and pyroelectric nature.Here,we demonstrate engineering of lysozyme into piezoelectric devices that can exploit the potential of lysozyme as environmentally friendly,biocompatible material for mechanical energy harvesting and sensorics,especially in micropowered electronic applications.Noteworthy that this flexible,shape adaptive devices made of crystalline lysozyme obtained from hen egg white exhibited a longitudinal piezoelectric charge coefficient(d-2.7 pC N^(-1))and piezoelectric voltage coefficient(g-76.24 mVmN^(-1))which are comparable to those of quartz(-2.3 pC N^(-1) and 50 mVmN^(-1)).Simple finger tapping on bio-organic energy harvester(BEH)made of lysozyme produced up to 350 mV peak-to-peak voltage,and a maximum instantaneous power output of 2.2 nW cm^(-2).We also demonstrated that the BEH could be used for self-powered motion sensing for real-time monitoring of different body functions.These results pave the way toward self-powered,autonomous,environmental-friendly bio-organic devices for flexible energy harvesting,storage,and in wearable healthcare monitoring. 展开更多
关键词 energy harvester LYSOZYME piezoelectric material self-powered motion sensing
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Ultrafast Joule heating technology for functional nanomaterials synthesis:Recent progress,challenges,and perspectives
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作者 Yuyu Liu Ruting Lin +6 位作者 Baoyi Guo Chen Chen Qiujin Wu Xiaofeng Zhang Qiufeng Huang Ibrahim Saana Amiinu Tingting Liu 《Materials Reports(Energy)》 2025年第4期11-34,共24页
Ultrafast Joule heating(JH)has emerged as a powerful and scalable platform for rapid thermal processing of advanced nanomaterials.By delivering transient,high-intensity electrical pulses,JH induces ultrafast heating a... Ultrafast Joule heating(JH)has emerged as a powerful and scalable platform for rapid thermal processing of advanced nanomaterials.By delivering transient,high-intensity electrical pulses,JH induces ultrafast heating and cooling rates on the order of milliseconds,facilitating nonequilibrium phase transitions,defect modulation,and tailored nanostructural evolution.This technique offers unprecedented control over material synthesis and has been successfully applied to a broad spectrum of functional property-driven materials,including graphene,single-atom catalysts,transition metal carbides,oxides,nitrides,phosphides,and chalcogenides,as well as complex multicomponent frameworks such as high-entropy alloys.This review systematically explores the principles governing JH,highlights recent advances in its application to diverse materials systems,and critically assesses current limitations related to process uniformity,scalability,and mechanistic understanding.Particular attention is given to its intrinsic advantages,including energy efficiency,fast rate,environmental sustainability,and compatibility with sustainable manufacturing.Finally,we propose guidance for expanding the utility of JH for new materials discovery,including integration with in-situ diagnostics,theoretical compatibility and data-driven optimization of synthesis to effectively correlate structure-property relationships. 展开更多
关键词 ELECTROCATALYSIS Energy storage and conversion Joule heating Materials synthesis Nanomaterials and ultrafast synthesis
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In situ loading of a pore network model for quantitative characterization and visualization of gas seepage in coal rocks
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作者 Huazhe Jiao Xi Chen +4 位作者 Tiegang Zhang Quilligan Michael Yixuan Yang Xiaolin Yang Tongyi Yang 《Deep Underground Science and Engineering》 2025年第3期437-451,共15页
The flow characteristics of coalbed methane(CBM)are influenced by the coal rock fracture network,which serves as the primary gas transport channel.This has a significant effect on the permeability performance of coal ... The flow characteristics of coalbed methane(CBM)are influenced by the coal rock fracture network,which serves as the primary gas transport channel.This has a significant effect on the permeability performance of coal reservoirs.In any case,the traditional techniques of coal rock fracture observation are unable to precisely define the flow of CBM.In this study,coal samples were subjected to an in situ loading scanning test in order to create a pore network model(PNM)and determine the pore and fracture dynamic evolution law of the samples in the loading path.On this basis,the structural characteristic parameters of the samples were extracted from the PNM and the impact on the permeability performance of CBM was assessed.The findings demonstrate that the coal samples'internal porosity increases by 2.039%under uniaxial loading,the average throat pore radius increases by 205.5 to 36.1μm,and the loading has an impact on the distribution and morphology of the pores in the coal rock.The PNM was loaded into the finite element program COMSOL for seepage modeling,and the M3 stage showed isolated pore connectivity to produce microscopic fissures,which could serve as seepage channels.In order to confirm the viability of the PNM and COMSOL docking technology,the streamline distribution law of pressure and velocity fields during the coal sample loading process was examined.The absolute permeability of the coal samples was also obtained in order for comparison with the measured results.The macroscopic CBM flow mechanism in complex lowpermeability coal rocks can be revealed through three-dimensional reconstruction of the microscopic fracture structure and seepage simulation.This study lays the groundwork for the fine description and evaluation of coal reservoirs as well as the precise prediction of gas production in CBM wells. 展开更多
关键词 coalbed methane fractal dimension FRACTURE pore network model SEEPAGE
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Keemun black tea stems and leaves:comparison of chemical characterization and anti-inflammatory activities
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作者 Mengting Zhu Xiaoqing Rong +5 位作者 Mingchun Wen Piaopiao Long Zongde Jiang Wen Xu Daniel Granato Liang Zhang 《Food Science and Human Wellness》 2025年第4期1546-1556,共11页
This work aims to compare the chemical composition and anti-inflammatory effects on RAW264.7 macrophages of Keemun black tea stems and leaves.A total of 50 volatile compounds were identified in tea stems and leaves,an... This work aims to compare the chemical composition and anti-inflammatory effects on RAW264.7 macrophages of Keemun black tea stems and leaves.A total of 50 volatile compounds were identified in tea stems and leaves,and aldehydes,alcohols,and esters were the main volatile compound categories.There were 11 key volatile compounds,including geraniol,benzeneacetaldehyde,methyl salicylate,linalool,etc.contributed to distinguishing the tea stems from the tea leaves.In the quantitative and liquid chromatography-mass spectrometry(LC-MS)-based metabolomics analysis,higher contents of amino acids,monosaccharides,and quinic acids were found in stems than those in leaves.Inversely,higher contents of tea pigments,flavan-3-ols,gallic acid,purine alkaloids,and flavonol glycosides were present in tea leaves than in stems.LC-MS-based metabolomics also revealed that organic acids were the most critical non-volatile compounds responsible for the differences between tea stems and leaves.Furthermore,tea stems had better inhibiting effects of pro-inflammatory cytokines(interleukin(IL)-1βand IL-6)in lipopolysaccharide-challenged RAW264.7 macrophages than tea leaves,while no significant differences exist between leaves and stems for inhibiting the secretion of tumor necrosis factorα(TNF-α)and NO.In conclusion,our results support using Keemun black tea stems as a novel source of anti-inflammatory compounds. 展开更多
关键词 Black tea stems Volatile compounds Non-volatile compounds Anti-inflammatory activities CYTOKINES
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Recent advances in multidimensional(1D,2D,and 3D)Joule heating devices based on cellulose:Design,structure,application,and perspective
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作者 Chuanyin Xiong Mengjie Zhao +6 位作者 Tianxu Wang Jing Han Yongkang Zhang Zhao Zhang Xianglin Ji Qing Xiong Yonghao Ni 《Journal of Materials Science & Technology》 2025年第2期53-78,共26页
The demand for flexible electric heating devices has increased due to technology advancement and improved living standards.These devices have various applications including personal thermal management,hyperthermia,def... The demand for flexible electric heating devices has increased due to technology advancement and improved living standards.These devices have various applications including personal thermal management,hyperthermia,defrosting,agricultural heating film,and oil-water separation.Joule heat,generated by electric currents,is commonly used in electrical appliances.To incorporate Joule heating into flexible electronics,new materials with excellent mechanical properties are necessary.Traditional polymers,used as reinforcements,limit the continuity of conductive networks in composites.Therefore,there is a need to develop flexible Joule thermal composite materials with enhanced mechanical strength and conductivity.Cellulose,a widely available renewable resource,is attracting attention for its excellent mechanical properties.It can be used as a dispersant and reinforcing agent for conductive fillers in cellulose-based composites,creating highly conductive networks.Various forms of cellulose,such as wood,nanocellulose,pulp fiber,bacterial cellulose,cellulose paper,textile clothing,and aramid fiber,have been utilized to achieve high-performance Joule thermal composites.Researchers have achieved excellent mechanical properties and developed efficient electric heating devices by designing cellulose-based composites with different structures.The scalable production methods enable large-scale application of cellulose-based devices,each with unique advantages in 1D,2D,and 3D structures.This review summarizes recent advancements in cellulose-based Joule thermal composites,providing insights into different structural devices,and discussing prospects and challenges in the field. 展开更多
关键词 CELLULOSE MULTIDIMENSIONAL Joule heating DESIGN PREPARATION
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Promoting men's health through sports clubs:A systematic rapid realist review
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作者 Anne Timm Aurelie van Hoye +8 位作者 Paul Sharp Tue Helms Andersen Louise Hansen Jane NautrupØstergaard Peter Krustrup Kenneth Cortsen Peter Bindslev Iversen Morten Hulvej Rod Charlotte Demant Klinker 《Journal of Sport and Health Science》 2025年第1期84-96,共13页
Background Health promotion(HP)interventions delivered through sports clubs have demonstrated promising outcomes among men,but less is known about which aspects of the interventions work,for whom,and under what circum... Background Health promotion(HP)interventions delivered through sports clubs have demonstrated promising outcomes among men,but less is known about which aspects of the interventions work,for whom,and under what circumstances.This rapid realist review aimed to understand the contexts,mechanisms,and outcomes of HP interventions for men delivered through sports clubs.Methods A systematic literature search was conducted in February 2023 for studies published after 2013 in MEDLINE,Embase,and SPORTDiscus databases.Included studies:(a)were delivered by or in collaboration with sports clubs,(b)targeted men aged 18+years,and(c)reported 1 or more HP outcomes.A grey literature search was also performed.Studies were included in a realist synthesis based on richness and rigor.Hereafter,context-mechanism-outcome(CMO)configurations were developed.Results We identified and screened 3358 studies,finally including 59 studies describing 22 interventions.Most HP interventions were delivered in high income countries,included Caucasian men aged 35-65 years with overweight/obesity,and used professional sports clubs(mostly football)for recruitment and facilities.Quantitative HP outcomes were reported across 19 interventions.Of these 19 interventions,the majority reported on weight(n=18),physical activity(n=12),mental health(n=10),and diet(n=9).We identified 13 CMOs related to how HP interventions affected men's recruitment,engagement,and health behavior maintenance.Conclusion Our findings show that using sports clubs for HP interventions is effective for engaging men.Recruitment was facilitated by leveraging sports clubs’identity,addressing masculinity-related barriers,improving accessibility,and building trust.Engagement was enhanced through shared identity experiences,safe spaces,inclusive competition,and self-efficacy.However,there's limited evidence on behavior maintenance post-intervention,though involving community stakeholders seemed vital.In general,considerations should be made to avoid perpetuating traditional masculine norms,which may exclude some men and reinforce unhealthy behaviors.These findings can guide intervention development,emphasizing the need to harness men's perspectives in the process. 展开更多
关键词 Community engagement Health promotion MASCULINITY Physical activity Sports clubs
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The Youth Fitness International Test(YFIT)battery for monitoring and surveillance among children and adolescents:A modified Delphi consensus project with 169 experts from 50 countries and territories
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作者 Francisco B.Ortega Kai Zhang +23 位作者 Cristina Cadenas-Sanchez Mark S.Tremblay Gregor Jurak Grant R,Tomkinson Jonatan R.Ruiz Katja Keller Christine Delisle Nystrom Jennifer MSacheck Russell Pate Kathryn LWeston Tetsuhiro Kidokoro Eric TPoon Lucy-Joy M.Wachira Ronald Ssenyonga Thayse Natacha Q.F.Gomes Carlos Cristi-Montero Brooklyn J.Fraser Claudia Niessner Vincent O.Onywera Yang Liu Li-Lin Liang Stephanie A.Prince Justin J.Lang the Delphi Fitness Expert Group 《Journal of Sport and Health Science》 2025年第4期48-63,共16页
Background:Physicalfitness in childhood and adolescence is associated with a variety of health outcomes and is a powerful marker of current and future health.However,inconsistencies in tests and protocols limit interna... Background:Physicalfitness in childhood and adolescence is associated with a variety of health outcomes and is a powerful marker of current and future health.However,inconsistencies in tests and protocols limit international monitoring and surveillance.The objective of the study was to seek international consensus on a proposed,evidence-informed,Youth Fitness International Test(YFIT)battery and protocols for health monitoring and surveillance in children and adolescents aged 618 years.Methods:We conducted an international modified Delphi study to evaluate the level of agreement with a proposed,evidence-based,YFIT of core health-relatedfitness tests and protocols to be used worldwide in 6-to 18-year-olds.This proposal was based on previous European and North American projects that systematically reviewed the existing evidence to identify the most valid,reliable,health-related,safe,and feasiblefitness tests to be used in children and adolescents aged 618 years.We designed a single-panel modified Delphi study and invited 216 experts from all around the world to answer this Delphi survey,of whom one-third are from low-to-middle income countries and one-third are women.Four experts were involved in the piloting of the survey and did not participate in the main Delphi study to avoid bias.We pre-defined an agreement of 80%among the expert participants to achieve consensus.Results:We obtained a high response rate(78%)with a total of 169fitness experts from 50 countries and territories,including 63 women and 61 experts from low-or middle-income countries/territories.Consensus(>85%agreement)was achieved for all proposed tests and protocols,supporting the YFIT battery,which includes weight and height(to compute body mass index as a proxy of body size/composition),the 20-m shuttle run(cardiorespiratoryfitness),handgrip strength,and standing long jump(muscularfitness).Conclusion:This study contributes to standardizingfitness tests and protocols used for research,monitoring,and surveillance across the world,which will allow for future data pooling and the development of international and regional sex-and age-specific reference values,health-related cut-points,and a global picture offitness among children and adolescents. 展开更多
关键词 FITNESS Experts DELPHI Protocols Youth Fitness International Test
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桉木化学-热磨机械浆纤维的生物改性研究 被引量:7
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作者 杨崎峰 詹怀宇 +2 位作者 王双飞 李可成 付时雨 《现代化工》 EI CAS CSCD 北大核心 2007年第1期32-35,37,共5页
采用白腐菌19-6对桉木化学-热磨机械浆(CTMP浆)进行了静置培养改性研究,探讨了附加营养物、pH、温度、培养时间和通氧方式等因素对处理效果的影响。结果表明,经白腐菌处理后的浆料二次磨浆能耗低于CTMP原浆,纸页的物理强度明显提高,在... 采用白腐菌19-6对桉木化学-热磨机械浆(CTMP浆)进行了静置培养改性研究,探讨了附加营养物、pH、温度、培养时间和通氧方式等因素对处理效果的影响。结果表明,经白腐菌处理后的浆料二次磨浆能耗低于CTMP原浆,纸页的物理强度明显提高,在游离度约为330 mL时,抗张指数提高21.3%,撕裂指数提高27.4%,内结合强度提高33.1%。同时白腐菌处理使纸浆白度和光散射系数分别下降了25%和21%,而不透明度基本没有变化,通过Na2S2O4+H2O2两段漂后可以使白度达到70.3%ISO,接近相同漂白工艺下CTMP原浆的白度。 展开更多
关键词 桉木CTMP浆 白腐菌19-6 生物改性
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溶解浆的质量要求及其生产技术 被引量:15
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作者 刘一山 陈春霞 +3 位作者 李建国 段超 郑林强 倪永浩 《中国造纸》 CAS 北大核心 2016年第2期56-61,共6页
溶解浆是一种高纯度的化学浆,是生产再生纤维素及纤维素衍生物的重要原料。本文在介绍溶解浆主要用途的基础上,对其质量要求进行详细分析,并介绍了溶解浆生产上一些特殊的处理方法。
关键词 溶解浆 质量要求 冷碱处理 热碱处理 酶处理
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采用冷碱抽提工艺改善溶解浆纤维素纯度的研究 被引量:15
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作者 田超 郑林强 +1 位作者 苗庆显 倪永浩 《中国造纸》 CAS 北大核心 2015年第4期1-6,共6页
纤维素纯度是溶解浆质量的首要要求。本研究采用冷碱抽提工艺,对溶解浆进行纯化处理,探讨了冷碱抽提主要工艺条件对抽提效果的影响;并与聚木糖酶处理工艺进行对比。结果表明,碱浓是影响抽提效果的最主要因素,在碱浓22%、浆浓20%、温度3... 纤维素纯度是溶解浆质量的首要要求。本研究采用冷碱抽提工艺,对溶解浆进行纯化处理,探讨了冷碱抽提主要工艺条件对抽提效果的影响;并与聚木糖酶处理工艺进行对比。结果表明,碱浓是影响抽提效果的最主要因素,在碱浓22%、浆浓20%、温度35℃、时间1 h抽提条件下,某预水解硫酸盐阔叶木溶解浆的α-纤维素含量由94.84%提高至98.51%;冷碱抽提对聚木糖类半纤维素具有很高的选择性,聚葡萄糖甘露糖类半纤维素需要冷碱抽提碱浓达到10%以上开始溶出;冷碱抽提在提高溶解浆纤维素纯度方面的作用明显优于聚木糖酶处理。 展开更多
关键词 溶解浆 Α-纤维素 冷碱抽提 半纤维素 聚木糖酶
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纤维的表面性能及表面分析技术 被引量:11
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作者 杨崎峰 詹怀宇 +1 位作者 王双飞 李可成 《中国造纸学报》 EI CAS CSCD 2005年第2期189-193,共5页
阐述了纤维表面性能的重要性,并主要介绍了扫描电镜(SEM)、透射电镜(TEM)、原子力显微镜(AFM)、激光共聚焦扫描显微镜(CLSM)、X射线光电子能谱(XPS)、二次离子质谱(SIMS)等现代表面分析技术及其在制浆造纸研究中的应用。
关键词 纤维 表面性能 表面分析技术
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临坡条形基础下地基极限承载力多因素影响规律的数值分析 被引量:3
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作者 李震 默杨 +2 位作者 任连伟 刘尚各 PHILLIPS Declan 《水利水电技术》 CSCD 北大核心 2018年第7期37-44,共8页
为了系统分析边坡对临坡基础极限承载力的影响,采用控制变量法和FLAC3D有限差分软件,分别针对不同坡顶距、坡角、相对密实度、基底宽度的荷载-位移曲线,研究了极限承载力、极限承载力弱化系数、极限承载力系数的多因素演化规律。结果表... 为了系统分析边坡对临坡基础极限承载力的影响,采用控制变量法和FLAC3D有限差分软件,分别针对不同坡顶距、坡角、相对密实度、基底宽度的荷载-位移曲线,研究了极限承载力、极限承载力弱化系数、极限承载力系数的多因素演化规律。结果表明:极限承载力、极限承载力弱化系数、极限承载力系数随坡顶距增加而增大,当坡顶距b与基底宽度B之比大于5时增长趋于停滞,但未达到平地地基数值;地基极限承载力、弱化系数随坡角增加近似线性减小,变化速率基本不受坡顶距的影响;地基极限承载力、极限承载力系数随砂土相对密实度增加而增大,同时受到坡顶距的影响,大坡顶距下随相对密实度的变化速率高于小坡顶距;地基极限承载力受基底宽度的影响程度小于坡顶距,随基底宽度增加小幅度增大,极限承载力系数随基底宽度的增大而减小;地基极限承载力弱化系数对相对密实度、基底宽度不敏感;减小坡角、提高相对密实度与增大坡顶距对极限承载力的提高有类似的效果,单纯通过增大坡顶距仍不能达到接近平地极限承载力的水平,适当地减小坡角、增加相对密实度可增大接近平地地基极限承载力的可能性。研究结果可为临坡工程施工方案选择提供借鉴,对推动临坡地基的工程定量计算具有重要作用。 展开更多
关键词 临坡基础 条形基础 极限承载力 多因素 数值分析 极限平衡法 滑移线场法
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白腐菌Trametes hirsuta 19-6预处理竹子化机浆的研究 被引量:5
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作者 熊建华 王双飞 李可成 《造纸科学与技术》 北大核心 2009年第3期19-23,共5页
研究了白腐菌对竹片进行生物预处理再进行化学机械法制浆的工艺和机理。生物预处理使竹子化机浆具有较好的物理强度。通过纤维特性分析,化机浆的纤维长度在生物预处理后增加,细小纤维含量降低。电子显微镜观测用来鉴定白腐菌预处理前后... 研究了白腐菌对竹片进行生物预处理再进行化学机械法制浆的工艺和机理。生物预处理使竹子化机浆具有较好的物理强度。通过纤维特性分析,化机浆的纤维长度在生物预处理后增加,细小纤维含量降低。电子显微镜观测用来鉴定白腐菌预处理前后竹浆纤维表面形态和内部结构的变化,纤维表面和内部细胞壁结构的变化有助于纸张强度的提高。 展开更多
关键词 CTMP竹浆 生物机械制浆 电子显微镜 纤维特性 白腐菌
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阳离子有机蒙脱石的制备与特征 被引量:3
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作者 刘温霞 倪永浩 肖惠宁 《中国造纸学报》 EI CAS CSCD 2005年第1期169-173,共5页
在树脂障碍控制中,阳离子疏水性树脂固着剂要比普通亲水性阳离子固着剂更有效,因此,阳离子疏水性的有机蒙脱石有望成为有效的树脂障碍控制剂。本实验阳离子有机蒙脱石由聚酰胺多胺环氧氯丙烷树脂对蒙脱石改性制备,并通过X射线衍射、傅... 在树脂障碍控制中,阳离子疏水性树脂固着剂要比普通亲水性阳离子固着剂更有效,因此,阳离子疏水性的有机蒙脱石有望成为有效的树脂障碍控制剂。本实验阳离子有机蒙脱石由聚酰胺多胺环氧氯丙烷树脂对蒙脱石改性制备,并通过X射线衍射、傅立叶变换红外光谱、热重分析、Zeta电位、电荷密度和粒度来表征。改性蒙脱石的Zeta电位、电荷密度和粒度随聚酰胺多胺分子质量的增加而增加,但高和低电荷密度的改性蒙脱石均对胶体状的分散松香酸表现出强烈的吸附作用。 展开更多
关键词 有机蒙脱石 阳离子 制备 傅立叶变换红外光谱 Zeta电位 树脂障碍控制剂 改性蒙脱石 特征 电荷密度 环氧氯丙烷 X射线衍射 水性树脂 热重分析 分子质量 吸附作用 固着剂 聚酰胺 亲水性 疏水性 松香酸 多胺 粒度
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制浆造纸工业中的染料 被引量:3
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作者 刘洪斌 杨淑慧 倪永浩 《染料与染色》 CAS 2008年第2期10-12,62,共4页
介绍了制浆造纸工业中常用的几种染料,即碱性染料、直接染料和颜料,介绍了这些染料的基本特性以及它们的染色理论。
关键词 染料 染色 调色 染色理论
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