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Carbon storage and net primary productivity in Canadian boreal mixedwood stands

journal of Forestry research 2019年第5期30卷 1667-1678页

作者： nicholas j.Payne D.Allan Cameron jean-Denis Leblanc Ian K.Morrison Canadian Forest Service Great Lakes Forestry Centre

Canadian boreal mixedwood forests are extensive,with large potential for carbon sequestration and storage;thus,knowledge of their carbon stocks at different stand ages is needed to adapt forest management practices to help meet climate-change mitigation *** stocks were quantified at three Ontario boreal mixedwood sites.A harvested stand,a juvenile stand replanted with spruce seedlings and a mature stand had total carbon stocks(±SE)of 133±13 at age 2,130±13 at age 25,and 207±15 Mg C ha^-1 at age 81 *** the clear-cut site,stocks were reduced by about 40%or 90 Mg C ha^-1 at *** held 27,34 and 62%of stocks,while detritus held 34,29 and 13%of stocks at age 2,25 and 81,*** soil carbon stocks averaged 51 Mg C ha^-1,and held 38,37 and 25%of *** net primary productivity(±SE)in the harvested and juvenile stand was 2.1±0.2 and 3.7±0.3 Mg C ha^-1 per annum(p.a.),compared to 2.6±2.5 Mg C ha^-1 *** the mature *** mature canopies studied had typical boreal mixedwood composition and mean carbon densities of 208 Mg C ha^-1,which is above average for managed Canadian boreal forest ecosystems.A comparison of published results from Canadian boreal forest ecosystems showed that carbon stocks in mixedwood stands are typically higher than coniferous stands at all ages,which was also true for stocks in vegetation and ***,aboveground net primary productivity was typically found to be higher in mixedwood than in coniferous boreal forest stands over a range of *** from this study,together with those published from the other boreal forest stands demonstrate the potential for enhanced carbon sequestration through modified forest management practices to take advantage of Canadian boreal mixedwood stand characteristics.

关键词： Aboveground net primary productivity Boreal mixedwood forest Carbon stocks Mixedwood stand management Stand age

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Assessing the academic achievement of United States orthopaedic departments

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World journal of Orthopedics 2022年第2期13卷 201-211页

作者： rishi Trikha Thomas E Olson Ameen Chaudry Chad r Ishmael Cristina Villalpando Clark j Chen Kellyn r Hori nicholas M Bernthal Department of Orthopaedic Surgery University of CaliforniaLos AngelesCA 90404United States Department of Orthopaedic Surgery David Geffen School of Medicine at UCLALos AngelesCA 90095United States

BACKGrOUND Assessing academic productivity allows academic departments to identify the strengths of their scholarly contribution and provides an opportunity to evaluate areas for *** To provide objective benchmarks for departments seeking to enhance academic productivity and identify those with significant improvement in recent *** Our study retrospectively analyzed a cohort of orthopaedic faculty at United States-based academic orthopaedic programs.5502 full-time orthopaedic faculty representing 178 programs were included in *** included for analysis were National Institutes of Health funding(2014-2018),leadership positions in orthopaedic societies(2018),editorial board positions of top orthopaedic journals(2018),total number of publications and Hirsch-index.A weighted algorithm was used to calculate a cumulative score for each academic *** study was performed at a large,United States medical *** All 178 programs included in analysis were evaluated using the comprehensive weighted *** five institutions with the highest cumulative score,in decreasing order,were:Washington University in ***,the Hospital for Special Surgery,Sidney Kimmel Medical College(SKMC)at Thomas jefferson University,the University of California,San Francisco(UCSF)and Massachusetts General Hospital(MGH)/Brigham and Women’s/*** five institutions with the highest score per capita,in decreasing order,were:Mayo Clinic(rochester),Washington University in ***,rush University,Virginia Commonwealth University(VCU)and MGH/Brigham and Women’s/*** five academic programs that had the largest improvement in cumulative score from 2013 to 2018,in decreasing order,were:VCU,SKMC at Thomas jefferson University,UCSF,MGH/Brigham and Women’s/Harvard,and Brown *** This algorithm can provide orthopaedic departments a means to assess academic productivity,monitor progress,and identify areas for improvement as th

关键词： Bibliometrics Academic achievement Number of publications National Institutes of Health funding Hirsch-index

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Vapors in the ambient-A complication in tribological studies or an engineering solution of tribological problems?

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Friction 2015年第2期3卷 85-114页

作者： Ala ALAZIZI Anthony j.BArTHEL nicholas D.SUrDYKA jiawei LUO Seong H.KIM Department of Chemical Engineering and Materials research Institute Pennsylvania State UniversityUniversity ParkPA 16802USA

Tribology involves not only two-body contacts of two solid materials-a substrate and a counter-surface;it often involves three-body contacts whether the third body is intentionally introduced or inevitably added during the sliding or *** intentionally added third body could be lubricant oil or engineered nano-material used to mitigate the friction and wear of the sliding *** inevitably added third body could be wear debris created from the substrate or the counter surface during *** in the absence of any solid third-body between the sliding surfaces,molecular adsorption of water or organic vapors from the surrounding environment can dramatically alter the friction and wear behavior of solid surfaces tested in the absence of lubricant *** review article covers the last case:the effects of molecular adsorption on sliding solid surfaces both inevitably occurring due to the ambient test and intentionally introduced as a solution for engineering *** will review how adsorbed molecules can change the course of wear and friction,as well as the mechanical and chemical behavior,of a wide range of materials under sliding conditions.

关键词： vapor phase lubrication environmental effect

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Feeding the world: impacts of elevated [CO_(2)] on nutrient content of greenhouse grown fruit crops and options for future yield gains

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Horticulture research 2023年第4期10卷 83-100页

作者： nicholas H.Doddrell Tracy Lawson Christine A.raines Carol Wagstaff Andrew j.Simkin NIAB New RoadEast MallingKentME196BJ UK Department of Food and Nutritional Sciences University of ReadingWhiteknightsReadingBerkshire RG66DZUK School of Life Sciences University of EssexColchester CO44SQUK School of Biosciences University of KentCanterburyUnited Kingdom CT27NJUK

Several long-term studies have provided strong support demonstrating that growing crops under elevated[CO_(2)]can increase photosynthesis and result in an increase in yield,flavour and nutritional content(including but not limited to Vitamins C,E and pro-vitamin A).In the case of tomato,increases in yield by as much as 80%are observed when plants are cultivated at 1000 ppm[CO_(2)],which is consistent with current commercial greenhouse productionmethods in the tomato fruit *** results provide a clear demonstration of the potential for elevating[CO_(2)]for improving yield and quality in greenhouse *** major focus of this review is to bring together 50 years of observations evaluating the impact of elevated[CO_(2)]on fruit yield and fruit nutritional *** the final section,we consider the need to engineer improvements to photosynthesis and nitrogen assimilation to allow plants to take greater advantage of elevated CO_(2) growth conditions.

关键词： crops greenhouse content

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Male and female meadow voles Microtus pennsylvanicus respond differently to scent marks from the top- middle-, and bottom-scent donors of an over-mark

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Current Zoology 2011年第4期57卷 441-448页

作者： Michael H. FErKIN nicholas j. HOBBS Benjamin D. FErKIN Adam C.FErKIN Daniel A. FErKIN Department of Biological Sciences The University of Memphis Ellington Hall Memphis TN 38152 USA

Previous studies have shown that individuals responded preferentially to the mark of the top-scent donor relative to that of the bottom-scent donor of an over-mark. However, terrestrial mammals are likely to encounter over-marks consisting of the scent marks of more than two same-sex conspecifics in the intersections of runways, near the nests of sexually receptive female conspecifics, and inside and along the borders of the territories of conspecifics. We determined how meadow voles, Microtus pennsylvanicus, respond to the marks of the top-, middle-, and bottom-scent donors of an over-mark. We tested the hypothesis that voles exposed to an over-mark will respond preferentially to the scent marks that were deposited more recently, the scent marks that were on top or near the top of the over-mark, compared to the scent marks that were deposited earlier or near the bot- tom of the over-mark. Voles spent more time investigating the mark of the top-scent donor than that of the either the middle- or bottom-scent donor. However, males but not female voles spent more time investigating the middle-scent mark than the bot- tom-scent mark. We also tested the hypothesis that voles evaluate and respond to over-marks differently from single scent marks. Voles spent more time investigating the marks of the top-, middle-, and bottom-scent donors compared to scent marks that were not part of the over-mark. Voles can distinguish among the overlapping scent marks of three scent donors and sex differences exist in the values they appear to attach to each of these scent marks [Current Zoology 57 （4）： 441-448, 2011 ].

关键词： Over-marks Voles Scent marks Olfactory communication

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The impact of storage conditions upon gentamicin coated antimicrobial implants

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journal of Pharmaceutical Analysis 2016年第6期6卷 374-381页

作者： nicholas D. Mullins Benjamin j. Deadman Humphrey A. Moynihan Florence O. McCarthy Simon E. Lawrence jonathan Thompson Anita r. Maguirea Department of Chemistry Analytical and Biological Chemistry Research Facility Synthesis and Solid State Pharmaceutical Centre University CollegeCork Ireland DePuy Synthes (Ireland) Loughbeg Ringaskiddy Co. Cork Ireland School of Pharmacy Analytical and Biological Chemistry Research Facility Synthesis and Solid State Pharmaceutical Centre University College CorkIreland

A systematic approach was developed to investigate the stability of gentamicin sulfate(GS) and GS/poly(lacticco-glycolic acid)(PLGA) coatings on hydroxyapatite *** influence of environmental factors(light,humidity,oxidation and heat) upon degradation of the drug in the coatings was investigated using liquid chromatography with evaporative light scattering detection and mass *** coated rods were found to be stable across the range of environments assessed,with only an oxidizing atmosphere resulting in significant changes to the gentamicin *** contrast,rods coated with GS/PLGA were more sensitive to storage conditions with compositional changes being detected after storage at 60 °C,75% relative humidity or exposure to *** effect of γ-irradiation on the coated rods was also investigated and found to have no significant ***,liquid chromatography–mass spectrometry analysis revealed that known gentamines C_1,C_1 aand C_2were the major degradants *** degradation of gentamicin coatings did not produce any unexpected degradants or impurities.

关键词： Gentamicin Coatings Storage stability testing LC–ELSD

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Diagnosis of morbid obesity may not impact healthcare utilization for orthotopic liver transplantation:A propensity matched study

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World journal of Hepatology 2017年第12期9卷 595-602页

作者： joshua r Peck nicholas Latchana Anthony Michaels Adam j Hanje Alice Hinton Elmahdi A Elkhammas Sylvester M Black Khalid Mumtaz Division of Gastroenterology Hepatology and Nutritionthe Ohio State University Wexner Medical Center Department of Surgery the Ohio State University Wexner Medical Center Department of Biostatistics the Ohio State University Wexner Medical Center

AIM To study mortality, length of stay, and total charges in morbidly obese adults during index hospitalization for orthotopic liver *** The Nationwide Inpatient Sample was queried to obtain demographics, healthcare utilization, post orthotopic liver transplantation(OLT) complications, and short term outcomes of OLT performed from 2003 to 2011(n = 46509). We divided patients into those with [body mass index(BMI) ≥ 40] and without(BMI rbid obesity. Multivariable logistic regression analysis was performedto characterize differences in in-hospital mortality, length of stay(LOS), and charges for OLT between patients with and without morbid obesity after adjusting for significant confounders. Additionally, propensity matching was performed to further validate the *** Of the 46509 patients who underwent OLT during the study period, 818(1.8%) were morbidly obese. Morbidly obese recipients were more likely to be female(46.8% vs 33.4%, P = 0.002), Caucasian(75.2% vs 67.8%, P = 0.002), in the low national income quartile(32.3% vs 22.5%, P = 0.04), and have ≥ 3 comorbidities(modified Elixhauser index; 83.9% vs 45.0%, P rbidly obese patient also had an increase in procedure related hemorrhage(P = 0.028) and respiratory complications(P = 0.043). Multivariate and propensity matched analysis showed no difference in mortality(Or: 0.70; 95%CI: 0.27-1.84, P = 0.47), LOS(β:-4.44; 95%CI:-9.93, 1.05, P = 0.11) and charges for transplantation(β: $15693; 95%CI:-51622-83008, P = 0.64) between the two groups. Morbidly obese patients were more likely to have transplants on weekdays(81.7%) as compared to those without morbid obesity(75.4%, P = 0.029).CONCLUSION Morbid obesity may not impact in-hospital mortality and health care utilization in OLT recipients. However, morbidly obese patients may be selected after careful assessment of co-morbidities.

关键词： Deceased donors Outcome Complications Economics Selection criteria

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Additive manufacturing(3D printing)of electrically conductive polymers and polymer nanocomposites and their applications

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eScience 2022年第4期2卷 365-381页

作者： Kirstie r.ryan Michael P.Down nicholas j.Hurst Edmund M.Keefe Craig E.Banks Faculty of Science and Engineering Manchester Metropolitan UniversityChester StreetManchesterM15GDUK

Additive manufacturing,or three-dimensional(3D)printing,offers a unique solution for fabricating complex geometries with high ***,many commercial additive manufacturing machines focus on the printing of polymers with limited ***,conductive polymers(CPs)can be processed to enable the additive manufacturing of conductive,low-density,and low-cost parts for a myriad of *** review summarizes the relevant achievements in the additive manufacturing of conductive polymers(CPs)and conductive polymer nanocomposites,with a discussion of the advantages and limitations of processing and printing these materials compared with alternative traditional manufacturing methods and their ***,the prospective applications of these additive manufacturing printed conductive materials are explored.

关键词： Conducting polymers Additive manufacturing Electrochemcial applications Supercapacitors Batteries

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Helicobacter pylori serology in a birth cohort of New Zealanders from age 11 to 26

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World journal of Gastroenterology 2005年第21期11卷 3273-3276页

作者： j.Paul Fawcett Gill O.Barbezat richie Poulton Barry j.Milne Harry H.X.Xia nicholas j.Talley School of Pharmacy University of Otago DunedinNew Zealand Dunedin School of Medicine University of Otago DunedinNew Zealand Dunedin Multidisciplinary Health and Development research Unit Dunedin School of Medicine University of Otago Dunedin New Zealand Department of Medicine The University of Hong Kong Queen Mary Hospital Hong Kong China Department of Medicine The University of Sydney Nepean HospitalNSW 2751Australia

AIM: To determine seroprevalence of Helicobacter pylori (Hpylori)in the Dunedin Multidisciplinary Health and Development Study (DMHDS) at age 26 in order to investigate seroconversion and seroreversion from age 11 to 26 and the association of seropositivity with risk factors for H pylori infection. METHODS: Participants in the DMHDS at age 26 and retrospectively at age 21 were tested for H pylori antibodies using two commercially available ELISA ***, socioeconomic status (SES), smoking,educational attainment and employment at age 26 were tested for association with H pylori seropositivity. rESULTS: At ages 21 and 26,seroprevalence of H pylori using one or other kit was 4.2% (n=795) and 6.3% (n=871) respectively, Seroreversion rate was lower than seroconversion rate (0.11% vs 0.53% per person-year) in contrast to the period from age 11 to 21 when seroreversion rate exceeded seroconversion rate (0.35% vs 0.11% per person-year). Serology in those tested at ages 11, 21, and 26 remained unchanged in 93.6% of the sample. Seroprevalence at age 26 was lower among those with a secondary school qualification (P=0.042) but was not associated with gender, SES, smoking or employment status. CONCLUSION: H pylori seroprevalence in a New Zealand birth cohort remains low between ages 11 and 26. H pylori infection remains stable from childhood to adulthood although seroreversion seems to be more common in the adolescent years than in young adults.

关键词： H pylori Seroprevalence Cohort

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用IrEFINDEr算法在非翻译区搜索人和小鼠的铁反应元件

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Acta Biochimica et Biophysica Sinica 2002年第6期34卷 743-747页

作者：陈新,王鲁泉,黄弋,邱平,MUrGOLO nicholas j.,GrEENE jonathan r.,吴才宏,姜颖北京大学生命科学学院生物信息中心 Schering Plough研究所北京大学生命科学学院生物信息中心 Schering Plough研究所 Schering Plough研究所 Schering Plough研究所北京大学膜及膜的工程国家重点实验室北京大学生命科学学院生物信息中心北京100871 Nj07033 北京100871 Nj07033 Nj07033 Nj07033 北京100871 北京100871

铁反应元件 (IrE)具有的高度保守的rNA茎环结构 ,是胞质中IrE结合铁调控蛋白 (IrP)的位点。IrP与IrE的结合受细胞内铁含量的调控 ,与铁代谢有着密切的关系。许多与铁代谢有关的基因在 5′UTr或 3′UTr都存在IrE。当铁离子缺乏时 ,IrE与... 详细信息

铁反应元件 (IrE)具有的高度保守的rNA茎环结构 ,是胞质中IrE结合铁调控蛋白 (IrP)的位点。IrP与IrE的结合受细胞内铁含量的调控 ,与铁代谢有着密切的关系。许多与铁代谢有关的基因在 5′UTr或 3′UTr都存在IrE。当铁离子缺乏时 ,IrE与IrP结合 ,使核糖体的翻译进程受阻 ,抑制mrNA的翻译 ;而当铁离子浓度较高时 ,IrP就释放IrE ,促进翻译。因此 ,IrE在 5′UTr调节着翻译的起始[1] 。如果IrE位于 3′UTr ,IrE与IrP的结合可以稳定mrNA并预防其被降解。所有已知的IrE均为C1G5型 ,即环的 1号和 5号碱基位置分别是保守的C和G ;另外还存在一类体外合成的U1A5型IrE ,即环的 1号和 5号碱基位置分别是保守的U和A ,能够在体外有效地结合IrP。由于IrE与铁代谢、氧化性损伤 (oxidativestress)和衰老等过程都有密切的关系 ,因此在临床及新药研制等方面都很受重视。通过改进搜索IrE的算法 ,用计算机程序对人与鼠的mrNA非编码区(UTr)序列数据库进行全面的搜索 ,期望找出可能存在的C1G5或U1A5类型的IrE ,或包含这两种类型IrE的基因。

关键词：铁反应元件铁调控蛋白茎环结构非翻译区

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