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Trace elements migrating from tailings to rock varnish laminated sediments in an old mining region from Nelson,Nevada,USA

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International Journal of Sediment Research 2022年第2期37卷 202-213页

作者： Douglas B.Sims Amanda C.Hudson John E.Keller michael Strange Andressa Cristhy Buch David Ferrari Giavanna m.Fernandez Juan Garcia-Hernandez Bailey D.Kesl sean Torres Department of Physical Sciences College of Southern Nevada University of Nevada Fluminense Federal University

The dispersion and influence of soluble and particulate trace elements(TEs) present in the materials from abandoned mines is an imminent problem on terrestrial and aquatic *** goal of this research is to provide a broader view of such transport,assessing particle size distribution and TE interactions(e.g.,scavenging) with mine tailings and locally derived sediments transported by water in arid *** grains from wash sediment were collected from a dry ephemeral wash in Nelson,Nevada where the Techatticup mine and mill worked between 1850 and *** were evaluated to determine the association and behavior of certain metals and metalloids including aluminum,arsenic,barium,cadmium,copper,chromium,iron,manganese,lead,selenium,vanadium,and zinc to rock varnish laminated *** show that some metals and metalloids were more concentrated on larger particles whereas others indicated the opposite *** example,As was greatest on silt fractions and least on coarse fractions,while Se was detected only on ***,Cu,Fe,mn,Pb,and Zn concentrations all increased with decreasing particle size(silt> sand> coarse),whereas Al,Ba,and V showed the opposite trend(silt ment factor(EF) of Cu,Zn,Pb,As,and Se were lower in mine tailing sediment treated with wash than those obtained for source *** in treated wash sediment samples,the high EFs of Ba,Cr,V,and mn suggested a possible greater affinity of these metals to the Al,Fe,and mn oxides from the RV *** data found in this study show that transport of contaminated sediments in arid regions could lead to the enrichment of some TEs in downgradient areas from source materials.

关键词： Adsorption metals metalloids mine tailings Particle size Transport

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Engineering Nannochloropsis oceanica for the production of diterpenoid compounds

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mLife 2023年第4期2卷 428-437页

作者： Zhi-Yan Du Wajid W.Bhat Eric Poliner sean Johnson Conor Bertucci Eva Farre Bjoern Hamberger Department of molecular Biosciences and Bioengineering University of Hawaii at ManoaHonoluluHawaiiUSA Department of Biochemistry and molecular Biology Michigan State UniversityEast LansingMichiganUSA Department of Plant Biology Michigan State UniversityEast LansingMichiganUSA New England Biolabs Inc. 240 County Roadlpswich01938 MAUSA

Photosynthetic microalgae like Nannochloropsis hold enormous potential as sustainable,light-driven biofactories for the production of high-value natural products such as *** oceanica is distinguished as a particularly robust host with extensive genomic and transgenic resources *** capacity to grow in wastewater,brackish,and sea waters,coupled with advances in microalgal metabolic engineering,genome editing,and synthetic biology,provides an excellent *** the present work,we demonstrate how *** can be engineered to produce the diterpene casbene—an important intermediate in the biosynthesis of pharmacologically relevant macrocyclic *** accumulated after stably expressing and targeting the casbene synthase from Daphne genkwa(DgTPS1)to the algal *** engineered strains yielded production titers of up to 0.12 mg g^(−1) total dry cell weight(DCW)*** overexpression and chloroplast targeting of two upstream rate-limiting enzymes in the 2-C-methyl-d-erythritol 4-phosphate pathway,Coleus forskohlii 1-deoxy-d-xylulose-5-phosphate synthase and geranylgeranyl diphosphate synthase genes,further enhanced the yield of casbene to a titer up to 1.80 mg g^(−1) *** results presented here form a basis for further development and production of complex plant diterpenoids in microalgae.

关键词： casbene microalgae plastid targeting synthetic biology terpene synthase

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Inflatable rock bolt bond strength versus rock mass rating (RmR)： A comparative analysis of pull-out testing data from underground mines in Nevada

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International Journal of mining Science and Technology 2016年第1期26卷 19-22页

作者： Barnard Chase Kallu Raj R. Warren sean Thareja Rahul Department of mining Engineering University of Nevada Reno 89557 USA

The purpose of this paper is to establish confidence in anticipated minimum bond strength for inflatable rock bolts by comparing the bond strength to variable geotechnical conditions using the rock mass rating （RmR） system. To investigate a correlation between these parameters, the minimum bond strength of pull-out tested inflatable rock bolts was compared to the RmR of the rock in which these bolts were placed. Bond strength vs. RmR plots indicate that expected minimum bond strength is positively corre- lated with RmR; however, the correlation is not strong. Cumulative percent graphs indicate that 97~; of pull-out tests result in a minimum bond strength of 3.3 and 1.7 ton/m in RmR/〉 45 and 〈45, respectively. Although lower bond strengths are more commonly encountered in low RmR ground, high bond strengths are possible as well, yielding higher variability in bond strengths in low RmR ground. Bond strength of friction bolts relies on contact between the rock bolt and drill hole. Experience in Nevada indicates that RmR is known to affect both the quality and consistency of drill holes which likely affects bond strength. Drilling and bolting in low RmR ground is more sensitive to drilling and bolting practices, and strategies for maximizing bond strength in these conditions are discussed.

关键词： Rock mass ratingRmRRock boltPull-out testBond strength

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Assessment of muscle strength in para-athletes:A systematic review of observational studies

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Sports medicine and Health Science 2022年第4期4卷 225-238页

作者： sean R.O'Connor Kristina Fagher Samuel Williamson Babette m.Pluim Clare L.Ardern Dina C.Janse van Rensburg Neil Heron Centre for Public Health Queen's University BelfastBelfastUK School of Psychology Queen's University BelfastBelfastUK Rehabilitation medicine Research Group Department of Health SciencesLund UniversityLundSweden English Institute of Sport ManchesterUK Royal Netherlands Lawn Tennis Association AmstelveenNetherlands Section Sports medicine Faculty of Health SciencesUniversity of PretoriaPretoriaSouth Africa Amsterdam Collaboration on Health&Safety in Sports(ACHSS) IOC Research Center of ExcellenceAmsterdam UMCAmsterdamNetherlands Department of Family Practice University of British ColumbiaVancouverCanada medical Board member World NetballManchesterUK School of medicine Keele UniversityStaffordshireUK

Accurate and reliable evaluation of muscle strength in para-athletes is essential for monitoring the effectiveness of strength training and/or rehabilitation programmes,and sport *** aim is to synthesise evidence related to assessing muscle strength in *** databases were searched from January 1990 to July 2021 for observational studies focusing on strength *** screening,data extraction,and quality assessment were performed in duplicate.A total of 1764 potential studies were *** met the inclusion criteria and were included in the *** mean age of participants was 30.7 years(standard deviation[SD]:2.4).The majority were men(88%)participating in wheelchair sports,including basketball,rugby,and tennis(23/30:76%).Overall quality varied,with more than half of the studies failing to identify strategies for dealing with confounding *** manual muscle testing being a standard component of para-sport classification systems,evidence examining strength characteristics in para-athletes is derived primarily from isometric and isokinetic *** studies that included comparative strength data,findings were *** studies found strength values were similar to or lower than able-bodied athletic ***,an important observation was that others reported higher shoulder strength in para-athletes taking part in wheelchair sports than both able-bodied and disabled *** need to develop accessible,standardised strength testing methods that account for training influence and establish normative strength values in *** is also a need for additional studies that include female para-athletes and para-athletes with greater functional impairments.

关键词： Systematic review Para-athletes Disabled sport muscle strength Assessment

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Controversies in fluid therapy: Type, dose and toxicity

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World Journal of Critical Care medicine 2014年第1期3卷 24-33页

作者： Robert C mcDermid Karthik Raghunathan Adam Romanovsky Andrew D Shaw sean m Bagshaw Division of Critical Care medicine Faculty of Medicine and Dentistry University of Alberta Edmonton AB T6G2B7 Canada Department of Anesthesiology Duke University Medical Center/Durham VAMC Durham NC 90484 United States Department of Critical Care medicine Duke University Medical Center/Durham VAMC Durham NC 90484 United States

Fluid therapy is perhaps the most common intervention received by acutely ill hospitalized patients; however, a number of critical questions on the efficacy and safety of the type and dose remain. In this review, recent insights derived from randomized trials in terms of fluid type, dose and toxicity are discussed. We contend that the prescription of fluid therapy is context-specific and that any fluid can be harmful if administered inappropriately. When contrasting ‘‘crystalloid vs colloid'', differences in efficacy are modest but differences in safety are significant. Differences in chloride load and strong ion difference across solutions appear to be clinically important. Phases of fluid therapy in acutely ill patients are recognized, including acute resuscitation, maintaining homeostasis, and recovery phases. Quantitative toxicity(fluid overload) is associated with adverse outcomes and can be mitigated when fluid therapy basedon functional hemodynamic parameters that predict volume responsiveness and minimization of non-essential fluid. Qualitative toxicity(fluid type), in particular for iatrogenic acute kidney injury and metabolic acidosis, remain a concern for synthetic colloids and isotonic saline, respectively. Physiologically balanced crystalloids may be the ‘‘default'' fluid for acutely ill patients and the role for colloids, in particular hydroxyethyl starch, is increasingly unclear. We contend the prescription of fluid therapy is analogous to the prescription of any drug used in critically ill patients.

关键词： Fluid therapy Resuscitation Critical illness Peri-operative Toxicity Saline Crystalloid Colloid

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Review of health risks of low testosterone and testosterone administration

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World Journal of Clinical Cases 2015年第4期3卷 338-344页

作者： Huanguang Jia Charles T Sullivan sean C mcCoy Joshua F Yarrow matthew morrow Stephen E Borst Center of Innovation on Disability and Rehabilitation Research North Florida/South Georgia Veterans Health System (151b) Pharmacy Services Malcom Randall VA Medical Center Geriatric Research Education and Clinical Center Malcom Randall VA Medical Center

Hypogonadism is prevalent in older men and testosteronereplacement therapy(TRT) for older hypogonadal men is a promising therapy. However, a number of important clinical concerns over TRT safety remain unsolved due to a lack of large-scale randomized clinical trials directly comparing the health risks of untreated hypogonadism vs long-term use of TRT. meta-analyses of clinical trials of TRT as of 2010 have identified three major adverse events resulting from TRT: polycythemia, an increase in prostate-related events, and a slight reduction in serum high-density lipoprotein cholesterol. There are other purported health risks but their incidence can be neither confirmed nor denied based on the small number of subjects that have been studied to date. Furthermore, subsequent literature is equivocal with regard to the safety and utility of TRT and this topic has been subject to contentious debate. Since January 2014, the United States Food and Drug Administration has released two official announcements regarding the safety of TRT and clinical monitoring the risks in TRT users. Additionally, the health risks related to the clinical presentation of low or declining testosterone levels not been resolved in the current literature. Because TRT is prescribed in the context of putative risks resulting from reduced testosterone levels, we reviewed the epidemiology and reported risks of low testosterone levels. We also highlight the current information about TRT utilization, the risks most often claimed to be associated with TRT, and current or emerging alternatives to TRT.

关键词： Hypogonadism Epidemiology Aging Low testosterone Testosterone replacement therapy

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Opposite effects of nitrogen fertilization and plastic film mulching on crop N and P stoichiometry in a temperate agroecosystem

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Journal of Plant Ecology 2019年第4期12卷 682-692页

作者： Fan Ding Shuangyi Li Xiao-Tao Lü Feike A.Dijkstra sean Schaeffer Tingting An Jiubo Pei Liangjie Sun Jingkuan Wang College of Land and Environment Shenyang Agricultural UniversityShenyang 110086China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China Sydney Institute of Agriculture School of Life and Environmental SciencesThe University of SydneyEveleighNSW 2015Australia Department of Biosystems Engineering and Soil Science University of TennesseeKnoxvilleTN 37996USA

Aims Crop nitrogen(N)and phosphorus(P)stoichiometry can influence food nutritive quality and many ecosystem ***,how and why N and P stoichiometry respond to long-term agricul-tural management practices(e.g.N fertilization and film mulching)are not clearly *** We collected maize tissues(leaf,stem,root and seed)and soil sam-ples from a temperate cropland under 30-year continuous N fer-tilization and plastic film mulching treatments,measured their C,N and P concentrations(the proportion(%)relative to the sample mass),and used structural equation models to uncover the re-sponding mechanisms for crop N and P contents(the total amount(g/m2)in crop biomass).Important Findings Long-term N fertilization increased N concentrations in all crop tissues but sharply decreased P concentrations in vegetative tis-sues(leaf,stem and root),thereby reducing their C/N ratio and increasing C/P and N/P *** drop in P concentration in vegetative tissues was due to the dilution effect by biomass in-crement and the priority of P supply for seed *** con-trast,film mulching decreased N concentration but increased P concentrations in most crop tissues,thereby increasing C/N ratio and reducing C/P and N/P *** mulching increased crop P content by increasing soil temperature and moisture;whereas,mulching showed little effect on crop N content,because a posi-tive effects of soil temperature may have canceled out a negative effect by soil *** indicated a decoupling of P and N uptake by crops under film *** conclusion,N fertiliza-tion and plastic film mulching showed opposite effects of on crop N and P stoichiometry.

关键词： long-term soil stoichiometry soil moisture dilution effect maize tissues

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Atrophy and Fibrosis of Extra-Ocular muscles in Anti-Acetylcholine Receptor Antibody myasthenia Gravis

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Open Journal of Ophthalmology 2014年第4期4卷 117-119页

作者： sean m. Gratton Angela Herro Jose Antonio Bermudez-magner John Guy Truman medical Center Department of Neurology and Cognitive Neuroscience University of Missouri—Kansas City School of Medicine Kansas City USA Bascom Palmer Eye Institute University of Miami Miller School of Medicine Miami USA

myasthenia gravis (mG) is an autoimmune disorder involving the neuromuscular junction that frequently affects the extra-ocular muscles (EOms). It has been described as a very rare cause of bilateral EOm atrophy, but histological analysis of such cases is lacking. A 66-year-old man presented with two months of right eyelid drooping and vertical diplopia. Examination showed bilateral ophthalmoparesis and complete right ptosis. The remainder of his exam was normal, and an mRI showed small EOms. Acetylcholine receptor antibodies were elevated, establishing the diagnosis of mG. Oral corticosteroids and pyridostigmine followed by azathioprine improved his ptosis, but not his ophthalmoparesis. One year later he had surgical correction of his diplopia, and the resected superior rectus muscle showed complete replacement of EOm by connective tissue. mG can rarely cause bilateral EOm atrophy, which is characterized histologically by fibrosis in the muscle itself. Atrophy in the EOms of a myasthenic patient may indicate a poor response to medical management alone.

关键词： myasthenia Gravis Oculomotor muscles muscular Atrophy

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Power Output and Electromyography Activity of the Back Squat Exercise with Cluster Sets

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Journal of Sports Science 2013年第1期1卷 37-45页

作者： Jordan m. Joy Jonathan m. Oliver sean A. mcCleary Ryan P. Lowery Jacob m. Wilson Department of Health Sciences and Human Performance The University of Tampa Tampa 33606 FL USA musclePharm Sports Science Institute MusclePharm Corp. Denver 80239 CO USA Department of Kinesiology Texas Christian University Fort Worth 76129 TX USA

Recently, it has been demonstrated that hypertrophic training with CLU （cluster） sets produces greater strength and power following a 12-week periodized program. The results suggest possible differences in neuromuscular adaptations. Therefore, we sought to compare the acute effect of TRD （traditional） and CLU set configurations during the parallel back squat on mean power output and integrated EmG （electromyography） activity of the VL （vastus lateralis） and BF （biceps femoris）. Ten males （23 ~ 2.4 years; height 182.9 ~ 6.1 cm; weight 86.2 ~ 4.2 kg; 5 ~ 2 years training） performed the parallel back squat using TRD and CLU with 75% 1Rm （one-repetition maximum） in a randomized crossover design. Data was analyzed by a repeated measures--ANOVA （analysis of variance）. A significant effect of set （P = 0.006） was observed in mean power output. mean power output decreased over each successive set when collapsed for condition. Clusters resulted in greater mean power output during latter repetitions of each set （repetition 4, 6-10; P 〈 0.05）. A significant effect of set （P = 0.049） was observed in VL EmG. VL EmG increased over each successive set when collapsed for condition. TRD training produced significantly greater VL EmG during latter repetitions of each set （repetition 6-8; P 〈 0.05）. An interaction was observed in BF EmG. No significant differences were observed in post-hoc. Thus, cluster sets can be used to achieve greater power output, but greater neuromuscular activity should not be expected relative to traditional training.

关键词： Cluster interset rest electromyography power squat intraset rest.

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双金属注射成形的刚性/耐耐磨零件

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粉末冶金技术 2015年第5期33卷 382-387页

作者： John L.Johnson Lye King Tan Ravi Bollina Pavan Suri randall m.German 韩凤麟 AmTellect Inc. State College PA 16801 Advanced materials Technologies Pte Ltd Singapore 609602 The Pennsylvania State University University Park PA 16802 不详

用mIm工艺,利用双色注射成形与共同烧结可制造双金属零件,但是,为了使收缩失配最小化,同时形成所期望的性能,必须使组成与烧结周期最佳化。烧结温度影响研究的m2工具钢与含硼316L不锈钢的烧结件的密度、硬度及力学性能。根据烧结时零件... 详细信息

用mIm工艺,利用双色注射成形与共同烧结可制造双金属零件,但是,为了使收缩失配最小化,同时形成所期望的性能,必须使组成与烧结周期最佳化。烧结温度影响研究的m2工具钢与含硼316L不锈钢的烧结件的密度、硬度及力学性能。根据烧结时零件的原位强度与热应力计算,预测了这些材料共同烧结的相容性。对于应用所需要的兼具刚性与耐磨性的316L-0.5B不锈钢/m2工具钢零件的成功生产,证明了这项预测。

关键词：注射成形双金属共同烧结

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