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Sub-stand diameter distribution types vary along an old-growth Douglas-fir chronosequence into the horizontal diversification development stage

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Journal of Forestry Research 2023年第2期34卷 415-424页

作者： jerilynn e.peck eric K.Zenner Department of ecosystem Science and Management The Pennsylvania State UniversityUniversity ParkPA 16802USA

Managing mature Douglas-fir[Pseudotsuga menziesii(Mirb.)Franco]stands to emulate the structural complexity of natural old-growth forest requires identifying structural targets at the sub-stand level at which neighborhood dynamics and patchy disturbance shape *** therefore sought to describe the archetypal shapes of predominant sub-stand diameter distribution types(DDTs)observed in natural tree neighborhoods in stands comprising a chronosequence(ca.120-450+yrs)encompassing mature,vertical diversification,and horizontal diversification development *** ten 1.0 ha stands are located in the southcentral Oregon Cascades,*** on the known spatial position of each tree,natural tree neighborhoods were identified using the floating neighborhood approach based on spatial tessellation connecting neighboring trees at the first-(mean 61 m2)through fifth-(mean 2058 m2)order *** analysis was then used to objectively identify the most predominant DDTs among the relative tree size distributions observed in the trans-scale neighborhoods within each *** measures regression was used to classify each DDT to one of six observed archetypal shapes:negative exponential,unimodal,rotated sigmoid,bimodal,concave,or *** three of the 81 observed DDTs deviated bye stand average,while every stand had at least one DDT that deviated by>50%(maximum 83%).Within each stand,five to ten predominant DDTs were observed,which deviated from the stand average by 30-48%and were characterized by two to five different archetypal ***,in some stands the majority of tree neighborhoods were best characterized by a different shape from that assigned at the stand *** from the stand average increased from the youngest stand in the mature development stage through the middle stands in the vertical diversification stage to the oldest stands in the horizontal diversification *** complexity of DDT shapes tended to increas

关键词： Diameter distribution type Floating neighborhood Restoration silviculture Small-scale Structural complexity

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Lipid nanoparticles deliver mRNA to the blood-brain barrier

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Nano Research 2024年第10期17卷 9126-9134页

作者： Yanina Kuzminich Avraham Shakked Randi Calkins Sebastian Rudden Camille Jones Jessie Doan Bora Jang elisa Schrader echeverri Ryan Zenhausern Liming Lian David Loughrey Hannah e.peck Rachelle Wiese Dorothy Koveal Philip J.Santangelo James e.Dahlman George C.Woodruff School of Mechanical engineering Georgia Institute of TechnologyAtlantaGA 30332USA Parker H.Petit Institute for Bioengineering and Biosciences Georgia Institute of TechnologyAtlantaGA 30332USA Wallace H.Coulter Department of Biomedical engineering Emory University School of Medicine and Georgia Institute of TechnologyAtlantaGA 30332USA

Lipid nanoparticles(LNPs)have delivered RNA to hepatocytes in patients after intravenous *** clinical data support efforts to design LNPs that transfect cells in the central nervous system(CNS).However,delivery to the CNS has been difficult,in large part because quantifying on-target delivery alongside common off-target cell types in adult mice remains *** we report methods to isolate different cell types from the CNS,and subsequently present mRNA delivery readouts using a liver-detargeted *** data suggest that LNPs without targeting ligands can transfect cerebral endothelial cells in mice after intravenous *** the difficulty of crossing the blood-brain barrier,they also underscore the value of quantifying delivery in the CNS with cell-type resolution instead of whole-tissue resolution.

关键词： lipid nanoparticle mRNA nanomedicine central nervous system blood-brain barrier

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紧锣密鼓的比特币装备竞赛

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科技纵览 2013年第6期 9-11页

作者： Morgen e.peck

强大的货币挖矿机正在改变流行的加密货币的属性。

关键词：竞赛装备比特货币加密

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区块链有黑暗的一面

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科技纵览 2016年第6期 12-13页

作者： Morgen e.peck

弗拉德-赞菲尔正在帮助以太坊打造一个世界，其中任何程序都可以使用比特币启发的技术。而且他真的对此很担忧。

关键词：区块链以太坊比特币黑暗

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Burn injury prevention in low-and middleincome countries:scoping systematic review

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Burns & Trauma 2021年第1期9卷 123-144页

作者： Kate Price Kwang Chear Lee Katherine e.Woolley Henry Falk Michael peck Richard Lilford Naiem Moiemen College of Medical and Dental Sciences University of BirminghamEdgbastonBirminghamB152TTUK University Hospital Birmingham NHS Foundation Trust Queen Elizabeth Hospital BirminghamMindelsohn WayEdgbastonBirminghamB152WBUK Institute of Applied Health Research University of BirminghamEdgbastonBirminghamB152TTUK Adjunct Professor of environmental Health Emory UniversityRollins School of Public HealthAtlantaGA 30322US Clinical Professor of Surgery University of Arizona College of MedicinePhoenixAZ 85004US

Background:Burn injuries are a leading cause of morbidity and disability,with the burden of disease being disproportionately higher in low-and middle-income countries(LMIC).Burn prevention programmes have led to significant reductions in the incidence of burns in high-income ***,a previous systematic review published in 2015 highlighted that implementation and evaluation of similar programmes has been limited in *** objective of this scoping review and narrative synthesis was to summarise and understand the initiatives that have been carried out to reduce burn injuries in LMIC and their ***:We aimed to identify publications that described studies of effectiveness of burn prevention interventions applied to any population within a LMIC and measured burn incidence or burns-related *** publications were identified from three ***,data was extracted from manuscripts identified in the systematic review published by Rybarczyk et *** then performed a search for manuscripts on burn prevention interventions published between January 2015 and September ***,we extracted data from two systematic reviews where burn evidence was not the primary outcome,which were identified by senior authors.A quality assessment and narrative synthesis of included manuscripts were ***:In total,24 manuscripts were identified and categorized according to intervention *** majority of manuscripts(n=16)described education-based *** manuscripts focused on environmental modification interventions and four adopted a mixedmethods *** of the education-based initiatives demonstrated improvements in knowledge relating to burn safety or first aid,however few measured the impact of their intervention on burn *** manuscripts described population-based educational interventions and noted reductions in burn *** one of the four manuscripts describing environmental modification i

关键词： Burns Prevention Low-and-middle income countries Systematic review

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Perioperative Use of Methotrexate and Tumor Necrosis Factor α Inhibitors Combination Therapy Is Not Likely to Increase Post-Operative Infection Rate in the National Veterans Health Administration Administrative Databases

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Open Journal of Rheumatology and Autoimmune Diseases 2019年第1期9卷 1-13页

作者： Hsin-Hsuan Juo Anders peck Sarah e. Monsell Bernard Ng Department of Medicine Division of Rheumatology University of Washington VA Puget Sound Healthcare System Seattle USA The Seattle Arthritis Clinic University of Washington Medicine Northwest Hospital Seattle USA Department of Biostatistics University of Washington Seattle USA

Objective: The aim of the study is to assess the risk of post-operative outcome in rheumatoid arthritis (RA) patients continuing versus stopping combination therapy of methotrexate (MTX) and hydroxychloroquine (HCQ) or tumor necrosis factor α inhibitors (TNF) prior to surgery. Methods: Using the United States Veterans Affairs (VA) databases, we identified surgical procedures in a 17-year cohort of RA patients. Among those patients, those on MTX + HCQ or MTX + TNF were identified. Post-operative outcome variables include infection, length of post-operative hospital stay and death. Results: We identified a total of 29,708 surgeries in RA patients. Among them, we identified the most recent elective surgeries without pre-operative infection in 16,174 patients. There were 783 and 550 patients on MTX + HCQ and MTX + TNF, respectively. The rates of post-op infection were 5% and 4% for the MTX + HCQ and MTX + TNF continuing medication groups, respectively, similar to the general RA population (5%). Sensitivity analyses at various time points of discontinuation combination therapies prior to surgery did not show significant change in terms of infection. Conclusions: The prevalence of adverse outcome is low. The proportion of post-operative infection in continuing and discontinuing medicine groups is similar for both MTX + HCQ and MTX + TNF. While we were unable to formally compare proportions of post-operative infection among the two groups, these preliminary findings do not support the hypothesis that continuing either MTX + TNF or MTX + HCQ combination during perioperative period increases post-operative infection compared with discontinuation prior to therapy.

关键词： Rheumatoid Arthritis Perioperative Management Outcome Methotrexate and Tumor Necrosis Factor Combination Therapy

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Multiyear Discrete Stochastic Programming with a Fuzzy Semi-Markov Process

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Applied Mathematics 2016年第6期7卷 482-495页

作者： C. S. Kim Richard M. Adams Dannele e. peck economic Research Service U.S. Department of Agriculture Washington DC USA Department of Applied economics Oregon State University Corvallis OR USA Department of Agricultural and Applied economics University of Wyoming Laramie WY USA

Drought conditions at a given location evolve randomly through time and are typically characterized by severity and duration. Researchers interested in modeling the economic effects of drought on agriculture or other water users often capture the stochastic nature of drought and its conditions via multiyear, stochastic economic models. Three major sources of uncertainty in application of a multiyear discrete stochastic model to evaluate user preparedness and response to drought are: (1) the assumption of independence of yearly weather conditions, (2) linguistic vagueness in the definition of drought itself, and (3) the duration of drought. One means of addressing these uncertainties is to re-cast drought as a stochastic, multiyear process using a “fuzzy” semi-Markov process. In this paper, we review “crisp” versus “fuzzy” representations of drought and show how fuzzy semi-Markov processes can aid researchers in developing more robust multiyear, discrete stochastic models.