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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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紧锣密鼓的比特币装备竞赛

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

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

Recent advances in room temperature phosphorescence of crystalline boron containing organic compounds

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Aggregate

Aggregate 2022年第4期3卷 15-22页

作者： hannah e.Hackney Dmitrii F.Perepichka Department of Chemistry McGill UniversityMontrealQCCanada

In organic compounds,room temperature phosphorescence(RTP)is a rare,yet highly desirable,property that is important for a wide variety of applications,including tissue imaging,anticounterfeiting technologies,photodynamic therapy,and organic light-emitting *** most organic RTP molecules rely on heavy atoms or carbonyl functional groups to accelerate singlet-to-triplet intersystem crossing,in the past few years there have been several reports of RTP induced by boroncontaining functional *** minireview covers the recent literature on RTP of crystalline boroorganic compounds and analyzes the connections between molecular structure,intermolecular interactions,and the resulting phosphorescence.

关键词： luminescence organic crystals organoboron chemistry room temperature phosphorescence

Impact of mechanical bowel preparation in elective colorectal surgery:A meta-analysis

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World Journal of Gastroenterology 2018年第4期24卷 519-536页

作者： Katie e Rollins hannah Javanmard-emamghissi Dileep N Lobo Gastrointestinal Surgery Nottingham Digestive Diseases Centre National Institute of Health Research (NIHR) Nottingham Biomedical Research Centre Nottingham University Hospitals NHS Trust and University of Nottingham Queen’s Medical Centre

AIM To analyse the effect of mechanical bowel preparation vs no mechanical bowel preparation on outcome in patients undergoing elective colorectal *** Meta-analysis of randomised controlled trials and observational studies comparing adult patients receiving mechanical bowel preparation with those receiving no mechanical bowel preparation, subdivided into those receiving a single rectal enema and those who received no preparation at all prior to elective colorectal surgery. ReSULTS A total of 36 studies(23 randomised controlled trials and 13 observational studies) including 21568 patients undergoing elective colorectal surgery were included. When all studies were considered, mechanical bowel preparation was not associated with any significant difference in anastomotic leak rates(OR = 0.90, 95%CI: 0.74 to 1.10, P = 0.32), surgical site infection(OR = 0.99, 95%CI: 0.80 to 1.24, P = 0.96), intraabdominal collection(OR = 0.86, 95%CI: 0.63 to 1.17, P = 0.34), mortality(OR = 0.85, 95%CI: 0.57 to 1.27, P = 0.43), reoperation(OR = 0.91, 95%CI: 0.75 to 1.12, P = 0.38) or hospital length of stay(overall mean difference 0.11 d, 95%CI:-0.51 to 0.73, P = 0.72), when compared with no mechanical bowel preparation, nor when evidence from just randomized controlledtrials was analysed. A sub-analysis of mechanical bowel preparation vs absolutely no preparation or a single rectal enema similarly revealed no differences in clinical outcome measures. CONCLUSION In the most comprehensive meta-analysis of mechanical bowel preparation in elective colorectal surgery to date, this study has suggested that the use of mechanical bowel preparation does not affect the incidence of postoperative complications when compared with no preparation. Hence, mechanical bowel preparation should not be administered routinely prior to elective colorectal surgery.

关键词： bowel preparation Mechanical antibiotics morbidity mortality surgery outcome complications meta-analysis

Paleoecological Response of Corals to the end-Triassic Mass extinction： An Integrational Analysis

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Journal of earth Science 2018年第4期29卷 879-885页

作者： George D Stanley Jr hannah M e Shepherd Autumn J Robinson University of Montana Paleontology Center Missoula MT 59812 USA

The end-Triassic （also Triassic-Jurassic） mass extinction severely affected life on planet earth 200 million years ago. Paleoclimate change triggered by the volcanic eruptions of the Central Atlantic Magmatic Province （CAMP） caused a great loss of marine biodiversity, among which 96% coral genera were get lost. However, there is precious little detail on the paleoecology and growth forms lost between the latest Triassic extinction and the early Jurassic recovery. Here a new pilot study was conducted by analyzing corallite integration levels among corals from the latest Triassic and early Jurassic times. Integration levels in corals from the Late Triassic and early Jurassic were determined through both the Paleobiology Database as well as from a comprehensive museum collection of fossil corals. Results suggest that in addition to a major loss of diversity following the end-Triassic mass extinction, there also was a significant loss of highly integrated corals as clearly evidenced by the coral data from the early Jurassic. This confirms our hypothesis of paleoecological selectivity for corals following the end-Triassic mass extinction. This study highlights the importance of assigning sim- ple to advanced paleoecological characters with integration levels, which opens a useful approach to understanding of mass extinction and the dynamics of the recovery.

关键词： coral loss integration level end-Triassic mass extinction paleoecology

Psychophysics of the hoverfly: categorical or continuous color discrimination?

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Current Zoology 2019年第4期65卷 483-492页

作者： Lea hannah Adrian G. Dyer Jair e. Garcia Alan Dorin Martin Burd School of Biological Sciences Monash University Clayton Victoria 3800 Australia Hawkesbury Institute for the environment Western Sydney University Richmond New South Wales 2753 Australia School of Media and Communication RMIT University Melbourne Victoria 3001 Australia Department of Physiology Monash University Clayton Victoria 3800 Australia Faculty of Information Technology Monash University Clayton Victoria 3800 Australia

There is increasing interest in flies as potentially important pollinators. Flies are known to have a complex visual system, in eluding 4 spectral classes of photoreceptors that con tribute to the perception of color. Our current understanding of how color signals are perceived by flies is based on data for the blowfly Lucilia sp., which after being conditi oned to rewarded mono chromatic light stimuli, showed evidenee of a categorical color visual system. The resulting opponent fly color space has 4 distinct categories, and has been used to interpret how some fly pollinators may perceive flower colors. However, formal proof that flower flies (Syrphidae) only use a simple, categorical color process remains outstanding. In free-flying experiments, we tested the hoverfly eristalis tenax, a Batesian mimic of the honeybee, that receives its nutrition by visiting flowers. Using a range of broadband similar-dissimilar color stimuli previously used to test color perception in pollinating hymenopteran species, we evaluated if there are steep changes in behavioral choices with continuously increasing color differences as might be expected by categorical color processing. Our data revealed that color choices by the hoverfly are mediated by a continuous monotonic function. Thus, these flies did not use a categorical processing, but showed evidenee of a color discrimination function similar to that observed in several bee species. We therefore empirically provide data for the minimum color distanee that can be discriminated by hoverflies in fly color space, enabling an improved un derstandi ng of plant-poll in ator interactions with a non-model insect species.

关键词： chromatic signal color model floral color fly pollination plant-pollinator vision

The CUL4A ubiquitin ligase is a potential therapeutic target in skin cancer and other malignancies

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Chinese Journal of Cancer 2013年第9期32卷 478-482页

作者： Jeffrey hannah Peng-Bo Zhou Department of Pathology and Laboratory Medicine Weill Cornell Medical College and Weill Cornell Graduate School of Medical Sciences Department of Pathology and Laboratory Medicine Weill Cornell Medical College

Cullin 4A(CUL4A)is an e3 ubiquitin ligase that directly affects DNA repair and cell cycle progression by targeting substrates including damage-specific DNA-binding protein 2(DDB2),xeroderma pigmentosum complementation group C(XPC),chromatin licensing and DNA replication factor 1(Cdt1),and *** work from our laboratory has shown that Cul4a-deficient mice have greatly reduced rates of ultraviolet-induced skin *** a cellular level,Cul4a-deficient cells have great capacity for DNA repair and demonstrate a slow rate of proliferation due primarily to increased expression of DDB2 and p21,*** suggests that CUL4A promotes tumorigenesis(as well as accumulation of skin damage and subsequent premature aging)by limiting DNA repair activity and expediting S phase *** addition,CUL4A has been found to be up-regulated via gene amplification or overexpression in breast cancers,hepatocellular carcinomas,squamous cell carcinomas,adrenocortical carcinomas,childhood medulloblastomas,and malignant pleural *** of its oncogenic activity in skin cancer and up-regulation in other malignancies,CUL4A has arisen as a potential candidate for targeted therapeutic *** this review,we outline the established functions of CUL4A and discuss the e3ligase’s emergence as a potential driver of tumorigenesis.

关键词：泛素连接酶恶性肿瘤皮肤癌治疗 DNA修复 DNA结合蛋白靶点细胞水平

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