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Contribution of national bioassessment approaches for assessing ecological water security: an AUSRIVAS case study 被引量:10
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作者 Susan J. nichols Fiona J. DYER 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2013年第5期669-687,共19页
River managers in Australia are managing in the face of extremes to provide security of water supply for people, production and the environment. Balancing the water requirements of people, environments and econo- mies... River managers in Australia are managing in the face of extremes to provide security of water supply for people, production and the environment. Balancing the water requirements of people, environments and econo- mies requires that water security is viewed holistically, not just in terms of the water available for human consump- tion. Common definitions of water security focus on the needs of both humans and ecosystems for purposes such as drinking, agriculture and industrial use, and to maintain ecological values. Information about achieving water security for the environment or ecological purposes can be a challenge to interpret because the watering require- ments of key ecological processes or assets are not well understood, and the links between ecological and human values are often not obvious to water users. Yet the concepts surrounding river health are inherently linked to holistic concepts of water security. The measurement of aquatic biota provides a valuable tool for managers to understand progress toward achieving ecological water security objectives. This paper provides a comprehensive review of the reference condition approach to river health assessment, using the development of the Australian River Assessment System (AUSRIVAS) as a case study. We make the link between the biological assessment of river health and assessment of ecological water security, and suggest that such an approach provides a way of reporting that is relevant to the contribution made by ecosystems to water security. The reference condition approach, which is the condition representative of minimally disturbed sites organized by selected physical, chemical, and biological characteristics, is most important for assessing ecological water security objectives. 展开更多
关键词 ecological water security biological assessment river health
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Urban and river flooding:Comparison of flood risk management approaches in the UK and China and an assessment of future knowledge needs 被引量:7
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作者 Matteo Rubinato Andrew nichols +5 位作者 Yong Peng Jian-min Zhang Craig Lashford Yan-peng Cai Peng-zhi Lin Simon Tait 《Water Science and Engineering》 EI CAS CSCD 2019年第4期274-283,共10页
Increased urbanisation,economic growth,and long-term climate variability have made both the UK and China more susceptible to urban and river flooding,putting people and property at increased risk.This paper presents a... Increased urbanisation,economic growth,and long-term climate variability have made both the UK and China more susceptible to urban and river flooding,putting people and property at increased risk.This paper presents a review of the current flooding challenges that are affecting the UK and China and the actions that each country is undertaking to tackle these problems.Particular emphases in this paper are laid on(1)learning from previous flooding events in the UK and China,and(2)which management methodologies are commonly used to reduce flood risk.The paper concludes with a strategic research plan suggested by the authors,together with proposed ways to overcome identified knowledge gaps in flood management.Recommendations briefly comprise the engagement of all stakeholders to ensure a proactive approach to land use planning,early warning systems,and water-sensitive urban design or redesign through more effective policy,multi-level flood models,and data driven models of water quantity and quality. 展开更多
关键词 Urban flooding River flooding Water management Review Strategic research plans Sponge cities
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Utility of MtCOI polymerase chain reaction-restriction fragment length polymorphism in differentiating between Q and B whitefly Bemisia tabaci biotypes 被引量:5
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作者 Wei-Hua Ma Xian-Chun Li +4 位作者 Timothy J. Dennehy Chao-Liang Lei Mo Wang Benjamin A. Degain Robert L. nichols 《Insect Science》 SCIE CAS CSCD 2009年第2期107-114,共8页
The invasive, insecticide-resistant, Q whitefly biotype, has gradually spread to other countries including the US via human-mediated movement of plant materials. We assessed the utility of the VspI-based mtCOI (mitoc... The invasive, insecticide-resistant, Q whitefly biotype, has gradually spread to other countries including the US via human-mediated movement of plant materials. We assessed the utility of the VspI-based mtCOI (mitochondrion cytochrome oxidase I) polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique as a rapid, cost-effective, and reliable alternative for differentiating the Q from the dominant B biotype in Arizona. Using the standard mtCOI gene sequencing and mtCOI PCR-RFLP techniques, we biotyped eight whitefly strains of five individuals each collected from poinsettia and cotton at different locations in Arizona. Complete concordance was observed between the two methods, with three strains being identified as the Q biotype and five samples as the B biotype. We also scanned the mtCOI gene sequences for VspI polymorphisms in the B and Q biotype whiteflies currently available in the GenBank database. This global screening revealed the existence of three and four VspI polymorphic types for the Q and B biotypes, respectively. Nevertheless, all three VspI polymorphic Q biotype whiteflies shared a common and unique VspI site that can be used to differentiate Q biotype from the four VspI polymorphic B biotype whiteflies identified. These results demonstrate that the VspI-based mtCOI gene PCR-RFLP provides a reliable diagnostic tool for differentiating the Q and B biotype whiteflies in the US and elsewhere. 展开更多
关键词 Bemisia tabaci BIOTYPE diagnosis tool mtCOI gene PCR-RFLP Vspl enzyme
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Effect of external and internal cues on core muscle activation during the Sahrmann five-level core stability test
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作者 Skyla Stifter Jessie McCaffrey +2 位作者 Tyler nichols Ayse Ozcan Edeer Justine Ward 《World Journal of Methodology》 2025年第1期95-104,共10页
BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of cor... BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of core muscle activation and a person's ability to stabilize the lumbopelvic complex.Preparatory cues and images can be used to increase the activation of these muscles.To attain optimal movement patterns,it will be necessary to determine what cueing will give the most effective results for core stability.AIM To investigate the effects of external and internal cues on core muscle activation during the Sahrmann five-level core stability test.METHODS Total 68 participants(21.83±3.47 years)were randomly allocated to an external(n=35)or internal cue group(n=33).Participants performed the Sahrmann fivelevel core stability test without a cue as baseline and the five-level stability exercises with an internal or external cue.External cue group received a pressure biofeedback unit(PBU),and the internal cue group received an audio cue.A Delsys Trigno^(TM)surface electromyography unit was used for muscle activation from the rectus abdominis,external oblique,and transverse abdominis/internal oblique muscles.RESULTS Linear mixed effects model analysis showed that cueing had a significant effect on core muscle activation(P=0.001);however,there was no significant difference between cue types(internal or external)(P=0.130).CONCLUSION Both external and internal cueing have significant effects on core muscle activation during the Sahrmann five-level core stability test and the PBU does not create higher muscle activation than internal cueing. 展开更多
关键词 External cue Internal cue Muscle activation Core muscles Lumbopelvic stability Pressure biofeedback unit
邓恩桉生长特性与生长应变研究 被引量:5
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作者 叶露 J.Doland nichols +1 位作者 Carolyn A.Raymond Kevin Glencross 《安徽农业科学》 CAS 2013年第10期4409-4410,4418,共3页
[目的]通过研究邓恩桉的生长特性和生长应变,为邓恩桉木材利用提供科学数据。[方法]以9.5年生人工林邓恩桉为研究对象,测定和评估树高(Ht)、胸径(DBH)、胸高比(DBH/Ht)、生长应变,并分析生长应变与生长性状的相关性。[结果]邓恩桉树高... [目的]通过研究邓恩桉的生长特性和生长应变,为邓恩桉木材利用提供科学数据。[方法]以9.5年生人工林邓恩桉为研究对象,测定和评估树高(Ht)、胸径(DBH)、胸高比(DBH/Ht)、生长应变,并分析生长应变与生长性状的相关性。[结果]邓恩桉树高、胸径和生长应变的小区间差异显著。胸径和生长应变的变化幅度分别为10.2~24.5 cm,-0.227~-0.064 mm。生长应变水平在上坡方向显著高于下坡方向。邓恩桉生长应变与树高、胸径、胸高比无显著相关性。[结论]邓恩桉可作为速生材培育,邓恩桉木材的生长应力不受生长性状的影响。实现高生长和选择低应力水平的速生邓恩桉作为实木加工是可行的。 展开更多
关键词 邓恩桉 生长应变 生长性状
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Elite,transformable haploid inducers in maize
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作者 Brent Delzer Dawei Liang +22 位作者 David Szwerdszarf Isadora Rodriguez Gonzalo Mardones Sivamani Elumalai Francine Johnson Samson Nalapalli Rachel Egger Erin Burch Kerry Meier Juan Wei Xiujuan Zhang Huaping Gui Huaibing Jin Huan Guo Kun Yu Yubo Liu Becky Breitinger Ana Poets Jason nichols Wan Shi David Skibbe Qiudeng Que Timothy Kelliher 《The Crop Journal》 SCIE CSCD 2024年第1期314-319,共6页
The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome edit... The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome editing(GE).Recently,these techniques were combined into a GE trait delivery system called HI-Edit(Haploid Inducer-Edit).In HI-Edit,the pollen of a haploid inducer line is reprogrammed to deliver GE traits to any variety,obviating recurrent selection.For HI-Edit to operate at scale,an efficient transformable HI line is needed,but most maize varieties are recalcitrant to transformation,and haploid inducers are especially difficult to transform given their aberrant reproductive behaviors.Leveraging marker assisted selection and a three-tiered testing scheme,we report the development of new Iodent and Stiff Stalk maize germplasm that are transformable,have high haploid induction rates,and exhibit a robust,genetically-dominant anthocyanin native trait that may be used for rapid haploid identification.We show that transformation of these elite‘‘HI-Edit”lines is enhanced using the BABYBOOM and WUSCHEL morphogenetic factors.Finally,we evaluate the HI-Edit performance of one of the lines against both Stiff Stalk and non-Stiff Stalk testers.The strategy and results of this study should facilitate the development of commercially scalable HI-Edit systems in diverse crops. 展开更多
关键词 Zea mays L Doubled haploids TRANSFORMATION Genome editing QTL
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Raman Spectroscopy for Forensic Identification of Body Fluid Traces: Method Validation for Potential False Negatives Caused by Blood-Affecting Diseases 被引量:1
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作者 Niara A. nichols Igor K. Lednev 《American Journal of Analytical Chemistry》 2022年第1期1-8,共8页
Two critical issues in forensic science are identifying body fluid traces found at crime scenes and preserving them for DNA analysis. However, the majority of current biochemical tests for body fluid identification, w... Two critical issues in forensic science are identifying body fluid traces found at crime scenes and preserving them for DNA analysis. However, the majority of current biochemical tests for body fluid identification, which are applicable at the crime scene, are presumptive and destructive to the sample. Raman Spectroscopy provides a suitable alternative to current methods as a nondestructive, confirmatory, and potentially in field method. Our laboratory has developed a chemometric model for the identification of five main body fluids using Raman spectroscopy. This model was developed using samples obtained from healthy donors. Thus, it is of most importance for the forensic application of the method to validate its performance for donors with diseases that might affect the biochemical composition of body fluids. In this study, the developed method was validated using peripheral blood samples acquired from donors with Celiac Disease, Sickle Cell Anemia, and Type 2 Diabetes. It was shown that the method correctly identified all samples as peripheral blood indicating that no false positives could occur because the blood traces were originated from donors suffering from the diseases. 展开更多
关键词 Raman Spectroscopy CHEMOMETRIC BLOODSTAIN False Negatives Body Fluids
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Electrocatalytic generation of reactive species and implications in microbial inactivation
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作者 Forrest nichols Kenneth I.Ozoemena Shaowei Chen 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第6期1399-1416,共18页
Controlling microbial proliferation in water systems,including wastewater,recreational water,and drinking water,is essential to societal health.Microbial inactivation through electrochemically generated reactive speci... Controlling microbial proliferation in water systems,including wastewater,recreational water,and drinking water,is essential to societal health.Microbial inactivation through electrochemically generated reactive species(RS)mediated pathways provides an effective route toward this microbial control.Herein we provide an overview of recent progress toward electrocatalytic generation of RS and their application in water disinfection,with a focus on the selective production of RS,the microorganism interactions with RS(including both RS mechanisms of action and innate microorganism responses to RS),and practical implementation of electrochemically generated RS for microbial inactivation.The article is concluded with a perspective where the challenges and opportunities of RS‐based electrochemical disinfection of water are highlighted,along with possible future research directions. 展开更多
关键词 ELECTROCATALYSIS Reactive species MICROORGANISM INACTIVATION Water electrodisinfection
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干眼的流行病学研究中评估患者自述的疾病分类
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作者 nichols J.J. Mitchell G.L. +1 位作者 nichols K.K 齐翔云 《世界核心医学期刊文摘(眼科学分册)》 2005年第2期32-33,共2页
PURPOSE. To evaluate the reliability of self-reported dry eye disease status and patient-related predictors of misclassification in contact lens wearers. ME THODS. Patients completed the Contact Lens Dry Eye Questionn... PURPOSE. To evaluate the reliability of self-reported dry eye disease status and patient-related predictors of misclassification in contact lens wearers. ME THODS. Patients completed the Contact Lens Dry Eye Questionnaire (CLDEQ) short form on two occ asions. Test-retest reliability of the CLDEQ composite score was determined usi ng the 95%limits of agreement (LoA) and an intraclass correlation coefficient ( ICC). The κstatistic was used to determine reliability of disease-classificati on-based CLDEQ composite score cutoff points. Predictors of misclassification w ere determined by multivariate logistic regression. RESULTS. The sample included 274 patients. The range of CLDEQ composite scores from both visits was -1.83 t o 4.50 and the mean difference between administrations was -0.05±0.75 (P=0.30) . The 95%LoA of the CLDEQ composite score were -1.51 to 1.42 and the ICC was 0 .61 (95%confidence interval CI: 0.53-0.68). Calculations using the lower lim it of the 95%CI showed that three administrations of the survey would be requir ed to obtain a more desirable ICC (0.70). The κstatistic for reliability of dry eye disease classification was 0.58 (95%CI: 0.48-0.67). Logistic regression s howed a significant interaction between gender (females) and younger age (P=0.02 ) in relation to misclassification of self-reported dry eye disease status. CON CLUSIONS. The reliability of selfreported dry eye disease classification in cont act lens wearers is moderate. In epidemiologic studies of factors associated wit h self-reported disease status, investigators may be well advised to consider u sing multiple administers of such outcome instruments and controlling for sociod emographic characteristics to maintain internal validity. 展开更多
关键词 疾病分类 患者自述 中评估 流行病学研究 接触镜 分类误差 可信限 组内相关系数 社会人口学特征 统计量
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Differential Cross Sections and Collision-Induced Rotational Alignment in Inelastic Scattering of NO(X)by Xe
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作者 Mark Brouard Helen Chadwick +6 位作者 Sean DSGordon Cornelia GHeid Balazs Hornung Bethan nichols Jacek Klos Pablo GJambrina FJavier Aoiz 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第2期217-233,I0003,J0001-J0017,共35页
Fully A-doublet resolved differential cross sections and collision-induced rotational alignment moments have been measured for the NO(X)-Xe collision system at a collision energy of 519 cm^-1.The experiments combine i... Fully A-doublet resolved differential cross sections and collision-induced rotational alignment moments have been measured for the NO(X)-Xe collision system at a collision energy of 519 cm^-1.The experiments combine initial quantum state selection,employing a hexapole inhomogeneous electric field,with quantum state resolved detection,using(1+1')resonantly enhanced multiphoton ionization and velocity map ion imaging.The differential cross sections and polarization dependent differential cross sections are shown to agree well with quantum mechanical scattering calculations performed on ab initio potential energy surfaces[J.Klos et al.J.Chem.Phys.137,014312(2012)].By comparison with quasi-classical trajectory calculations,quantum mechanical scattering calculations on a hard-shell potential,and kinematic apse model calculations,the effects of the attractive part of the potential on the measured differential cross sections and collision-induced rotational alignment moments are assessed. 展开更多
关键词 Chemical Physics Reaction dynamics Inelastic scattering
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Estimating above-ground biomass by fusion of LiDAR and multispectral data in subtropical woody plant communities in topographically complex terrain in North-eastern Australia 被引量:2
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作者 Sisira Ediriweera Sumith Pathirana +1 位作者 Tim Danaher Doland nichols 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第4期761-771,共11页
We investigated a strategy to improve predicting capacity of plot-scale above-ground biomass (AGB) by fusion of LiDAR and Land- sat5 TM derived biophysical variables for subtropical rainforest and eucalypts dominate... We investigated a strategy to improve predicting capacity of plot-scale above-ground biomass (AGB) by fusion of LiDAR and Land- sat5 TM derived biophysical variables for subtropical rainforest and eucalypts dominated forest in topographically complex landscapes in North-eastern Australia. Investigation was carried out in two study areas separately and in combination. From each plot of both study areas, LiDAR derived structural parameters of vegetation and reflectance of all Landsat bands, vegetation indices were employed. The regression analysis was carded out separately for LiDAR and Landsat derived variables indi- vidually and in combination. Strong relationships were found with LiDAR alone for eucalypts dominated forest and combined sites compared to the accuracy of AGB estimates by Landsat data. Fusing LiDAR with Landsat5 TM derived variables increased overall performance for the eucalypt forest and combined sites data by describing extra variation (3% for eucalypt forest and 2% combined sites) of field estimated plot-scale above-ground biomass. In contrast, separate LiDAR and imagery data, andfusion of LiDAR and Landsat data performed poorly across structurally complex closed canopy subtropical minforest. These findings reinforced that obtaining accurate estimates of above ground biomass using remotely sensed data is a function of the complexity of horizontal and vertical structural diversity of vegetation. 展开更多
关键词 FUSION above-ground biomass LiDAR multispectral data subtropical plant communities
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可控源大地电磁法探测地下水 被引量:2
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作者 Edward A.nichols H.Frank Morrison +1 位作者 Sounghee Lee 贺宁波 《国外地质勘探技术》 1996年第3期7-9,共3页
张量音频大地电磁法(AMT)和张量可控源音频大地电磁法(CSAMT)近来在浅层高分辨率电导率填图方面有了很大发展,为使频率连续且范围从1—100kHz,采用了便携式直立回线发射器以补充频率高于1kHz的天然场讯号的不足,在加利福尼亚沙林那斯谷... 张量音频大地电磁法(AMT)和张量可控源音频大地电磁法(CSAMT)近来在浅层高分辨率电导率填图方面有了很大发展,为使频率连续且范围从1—100kHz,采用了便携式直立回线发射器以补充频率高于1kHz的天然场讯号的不足,在加利福尼亚沙林那斯谷地咸水侵入研究中采集的野外数据推断出的水文地质特征与监视井测井资料相吻合。 展开更多
关键词 地下水 探测 大地电磁法 可控源
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Rapid preparation of carbon-supported ruthenium nanoparticles by magnetic induction heating for efficient hydrogen evolution reaction in both acidic and alkalinemedia 被引量:2
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作者 Qiming Liu Bingzhang Lu +4 位作者 Forrest nichols Jeffrey Ko Rene Mercado Frank Bridges Shaowei Chen 《SusMat》 2022年第3期335-346,共12页
Ruthenium has been hailed as a competitive alternative for platinum toward hydrogen evolution reaction(HER),a critical process in electrochemical water splitting.In this study,we successfully prepare metallic Ru nanop... Ruthenium has been hailed as a competitive alternative for platinum toward hydrogen evolution reaction(HER),a critical process in electrochemical water splitting.In this study,we successfully prepare metallic Ru nanoparticles supported on carbon paper by utilizing a novel magnetic induction heating(MIH)method.The samples are obtained within seconds,featuring a Cl-enriched surface that is unattainable via conventional thermal annealing.The best sample within the series shows a remarkable HER activity in both acidic and alkaline media with an overpotential of only-23 and-12 mV to reach the current density of 10 mA/cm^(2),highly comparable to that of the Pt/C benchmark.Theoretical studies based on density functional theory show that the excellent electrocatalytic activity is accounted by the surface metal-Cl species that facilitate charge transfer and downshift the d-band center.Results from this study highlight the unique advantages of MIH in rapid sample preparation,where residual anion ligands play a critical role in manipulating the electronic properties of the metal surfaces and the eventual electrocatalytic activity. 展开更多
关键词 Cl-enriched surface density functional theory hydrogen evolution reaction magnetic induction heating RUTHENIUM
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Endothelin-1 activation in pediatric patients undergoing surgical coarctation of the aorta repair 被引量:2
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作者 Benjamin Steven Frank Tracy T Urban +4 位作者 Suhong Tong Courtney Cassidy Max B Mitchell Christopher S nichols Jesse A Davidson 《World Journal of Cardiology》 CAS 2017年第12期822-829,共8页
AIM To determine endothelin-1(ET-1)concentration before and after surgical coarctectomy and evaluate its association with left ventricular geometric change.METHODSA prospective,cohort study of 24 patients aged 2 d to ... AIM To determine endothelin-1(ET-1)concentration before and after surgical coarctectomy and evaluate its association with left ventricular geometric change.METHODSA prospective,cohort study of 24 patients aged 2 d to 10years with coarctation of the aorta undergoing surgical repair.A sub-cohort of patients with age<1 mo was classified as"neonates".Echocardiograms were performed just prior to surgery and in the immediate post-op period to assess left ventricle mass index and relative wall thickness(RWT).Plasma ET-1 levels were assessed at both time points.Association between ET-1 levels and ventricular remodeling was assessed.RESULTSPatients<1 year demonstrated higher pre-op ET-1 than post-op(2.8 pg/m L vs 1.9 pg/m L,P=0.02).Conversely,patients>1 year had no change in ET-1 concentration before and after surgery(1.1 vs 1.4,NS).Pre-op,patients<1 year demonstrated significantly higher ET-1 than older children(2.8 vs 1.1,P=0.001).Post-op there was no difference between the age groups(1.9 vs 1.4,NS).Neither RWT nor left ventricle mass index(LVMI)varied from pre-op to post-op.The subset of neonates showed a strong positive correlation between pre-op ET-1 and RWT(r=0.92,P=0.001).Patients with ET-1>2 pg/m L preop demonstrated higher LVMI(65.7 g/m^(2.7) vs 38.5 g/m^(2.7),P=0.004)and a trend towards higher RWT(45%vs39%,P=0.07)prior to repair than those with lower ET-1concentration.CONCLUSIONET-1 concentration is significantly variable in the perioperative period surrounding coarctectomy.Older children and infants have different responses to surgical repair suggesting different mechanisms of activation. 展开更多
关键词 Biomarkers Cardiac REMODELING PEDIATRIC NEONATE Left VENTRICULAR HYPERTROPHY
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Performances of Concrete under Elevated Curing Temperature 被引量:2
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作者 谭克锋 John M nichols 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第3期65-67,共3页
The behaviors of concrete at elevated curing temperature were studied. The test results show that when concrete is cured at elevated temperature, a harmful consequence occurs.The later strength decreases significantly... The behaviors of concrete at elevated curing temperature were studied. The test results show that when concrete is cured at elevated temperature, a harmful consequence occurs.The later strength decreases significantly compared to that under normal curing condition. Incorporating silica fume, fly ash and slag or lowering w/c ratio can effectively alleviate this harmful consequence. Comparatively, incorporation of silica fume is the most efficient means to decrease the later strength reduction. The harmful consequence is not caused by the difference in degree of hydration since the degree of hydration is similar between elevated curing temperature and normal curing condition. The SEM analysis shows that it is the uneven distribution of hydration products caused by elevated curing temperature that leads to the later strength reduction of concrete. 展开更多
关键词 curing temperature STRENGTH mineral admixture
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Proton therapy for pancreatic cancer 被引量:2
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作者 Romaine C nichols Soon Huh +1 位作者 Zuofeng Li Michael Rutenberg 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2015年第9期141-147,共7页
Radiotherapy is commonly offered to patients with pancreatic malignancies although its ultimate utility is compromised since the pancreas is surrounded by exquisitely radiosensitive normal tissues, such as the duodenu... Radiotherapy is commonly offered to patients with pancreatic malignancies although its ultimate utility is compromised since the pancreas is surrounded by exquisitely radiosensitive normal tissues, such as the duodenum, stomach, jejunum, liver, and kidneys. Proton radiotherapy can be used to create dose distributions that conform to tumor targets with significant normal tissue sparing. Because of this, protons appear to represent a superior modality for radiotherapy delivery to patients with unresectable tumors and those receiving postoperative radiotherapy. A particularly exciting opportunity for protons also exists for patients with resectable and marginally resectable disease. In this paper, we review the current literature on proton therapy for pancreatic cancer and discuss scenarios wherein the improvement in the therapeutic index with protons may have the potential to change the management paradigm for this malignancy. 展开更多
关键词 PROTON THERAPY PANCREATIC CANCER REVIEW
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Optimizing neoadjuvant radiotherapy for resectable and borderline resectable pancreatic cancer using protons 被引量:2
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作者 Romaine Charles nichols Michael Rutenberg 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2019年第7期303-307,共5页
Approximately 25%of patients diagnosed with pancreatic cancer present with non-metastatic resectable or borderline resectable disease.Unfortunately,the cure rate for these“curable”patients is only in the range of 20... Approximately 25%of patients diagnosed with pancreatic cancer present with non-metastatic resectable or borderline resectable disease.Unfortunately,the cure rate for these“curable”patients is only in the range of 20%.Local-regional failure rates may exceed 50%after margin-negative,node-negative pancreatectomy,but up to 80%of resections are associated with regional lymph node or margin positivity.While systemic drug therapy and chemotherapy may prevent or delay the appearance of distant metastases,it is unlikely to have a significant impact on local-regional disease control.Preoperative radiotherapy would represent a rational intervention to improve local-regional control.The barrier to preoperative radiotherapy is the concern that it could potentially complicate what is already a long and complicated operation.When the radiotherapy is delivered with X-rays(photons),the entire cylinder of the abdomen is irradiated;therefore,an operating surgeon may be reluctant to accept the associated risk of increased toxicity.When preoperative radiotherapy is delivered with protons,however,significant bowel and gastric tissue-sparing is achieved and clinical outcomes indicate that proton therapy does not increase the risk of operative complications nor extend the length of the procedure. 展开更多
关键词 Radiation ONCOLOGY PANCREATIC cancer PROTON therapy
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Use of a saline-coupled bipolar sealer open liver resection for hepatic malignancy: Medical resource use and costs 被引量:1
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作者 Christine I nichols Joshua G Vose 《World Journal of Gastroenterology》 SCIE CAS 2016年第46期10189-10197,共9页
AIM To evaluate outcomes associated with use of a saline coupled bipolar sealer during open partial liver resection.METHODS This retrospective analysis utilized the United States Premier? insurance claims database(201... AIM To evaluate outcomes associated with use of a saline coupled bipolar sealer during open partial liver resection.METHODS This retrospective analysis utilized the United States Premier? insurance claims database(2010-2014). Patients were selected with codes for liver malignancy and partial hepatectomy or lobectomy. Cases were defined by use the saline-coupled bipolar sealer; controls had no use. A Propensity Score algorithm was used to match one case to five controls. A deviationbased cost modeling(DBCM) approach provided an estimate of cost-effectiveness.RESULTS One hundred and forty-four cases and 720 controls were available for analysis. Patients in the case cohort received fewer transfusions vs controls(18.1% vs 29.4%, P = 0.007). In DBCM, more patients in the case cohort experienced "on-course" hospitalizations(53.5% vs 41.9%, P = 0.009). The cost calculation showed an average savings in total hospitalization costs of $1027 for cases vs controls. In multivariate analysis, cases had lower odds of receiving a transfusion(OR = 0.44, 95%CI: 0.27-0.71, P = 0.0008).CONCLUSION Use of a saline-coupled bipolar sealer was associated with a greater proportion of patients with an "on course" hospitalization. 展开更多
关键词 Liver resection hepatocellular carcinoma COSTS
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Advances in lower extremity peripheral nerve surgery
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作者 Anna Garbuzov Ramin Shekouhi +1 位作者 D.Spencer nichols Harvey Chim 《Plastic and Aesthetic Research》 2023年第1期513-528,共16页
Peripheral nerve injury(PNI)is a common source of pain and disability in patients.While many patients are affected by PNI,peripheral nerve surgery advancements in the lower extremity have lagged behind the upper extre... Peripheral nerve injury(PNI)is a common source of pain and disability in patients.While many patients are affected by PNI,peripheral nerve surgery advancements in the lower extremity have lagged behind the upper extremity.Subsequently,principles that have demonstrated success in the upper extremity have been implemented in the lower extremity.Interventions with recent advances include the advent of novel nerve transfers in the lower extremity and using stem cells and electrical stimulation(ES)for nerve regeneration.This article focuses on advances in nerve transfers for lower extremity PNI and provides details on the basic science and clinical applications of newer interventions. 展开更多
关键词 Stem cells peripheral nerve SURGERY nerve transfer electrical stimulation nerve repair nerve regeneration
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了解、优化和测试水在汽车外饰件涂层氙灯加速老化测试中的作用 被引量:1
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作者 M.nichols T.Misovski +6 位作者 K.Henderson D.Smith J.Boisseau L.Pattison J.Quill 张恒 孙杏蕾 《汽车工艺与材料》 2010年第9期62-70,共9页
目前测试涂层老化的最佳加速方法是SAEJ2527。该方法规定在氙灯箱内进行老化试验,经滤光片过滤后,氙灯光源产生与太阳光相似的光谱功率分布(SPD);而且氙灯试验箱内的温度、湿度和在油漆样品上喷淋的液态水都能得到控制,希望能在短时间... 目前测试涂层老化的最佳加速方法是SAEJ2527。该方法规定在氙灯箱内进行老化试验,经滤光片过滤后,氙灯光源产生与太阳光相似的光谱功率分布(SPD);而且氙灯试验箱内的温度、湿度和在油漆样品上喷淋的液态水都能得到控制,希望能在短时间内模拟与佛罗里达户外曝晒相当的涂层失效状况。为了探究水在加速老化测试中的作用,保证水的类型(湿度或液态水)和水侵蚀时间必须与户外规定地点的水的类型和水侵蚀时间相一致,本文介绍了油漆样品在佛罗里达及其他地区户外曝晒条件中的水的量和类型的细节分析,还介绍了油漆样品在执行SAEJ2527测试标准的老化设备中曝晒时的水喷淋量,并将这些结果进行相互比较,得出不同油漆体系的最大理论用水量,从数据可以分析出使用不同老化设备对油漆样品进行测试时的用水量是不同的。我们得出的带有建议性的结论是,通过改进加速老化的测试条件,可以在较短时间内提供更精确的结果。 展开更多
关键词 氙灯光源 老化测试 涂层老化 试水 外饰件 汽车 优化 光谱功率分布
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