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Impact of deforestation on habitat connectivity thresholds for large carnivores in tropical forests

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Ecological processes 2017年第1期6卷 214-224页

作者： Miriam A.Zemanova Humberto L.perotto-Baldivieso Emily L.Dickins Andrew B.Gill John p.leonard David B.Wester School of Energy Environment and AgrifoodCranfield UniversityCranfield MK430ALUK Institute of Ecology and Evolution University of BernBaltzerstrasse 63012 BernSwitzerland Caesar Kleberg Wildlife Research Institute Texas A&M University-Kingsville700 University Blvd.MSC 218KingsvilleTX 78363USA Museo de Historia Natural Noel Kempff Mercado Universidad Autónoma Gabriel Rene MorenoAvenida Irala 565Santa Cruz de la SierraBolivia Hensmans Farm Nearton EndSwanbourne MK170SLUK Cape Eleuthera Institute EleutheraBahamas

Introduction:Deforestation significantly impacts large carnivores that depend on large tracts of interconnected forest habitat and that are sensitive to human *** the relationship between habitat use and spatial distribution of such species across human modified landscapes is critical when planning effective conservation *** study assessed the presence of potential landscape connectivity thresholds resulting from habitat fragmentation associated with different deforestation patterns using a scale-based approach that links species-specific home ranges with the extent of anthropogenic *** objectives were(1)to quantify the spatial and temporal distribution of natural vegetation for five common deforestation patterns and(2)to evaluate the connectivity associated with these patterns and the existence of potential thresholds affecting jaguar *** Bolivian lowlands,located within jaguar conservation units,were analysed with landscape metrics to capture the spatial and temporal changes within deforested areas and to determine potential impact on jaguar connectivity and connectivity thresholds for ***:Over the period of 1976–2005,the amount of natural vegetation has decreased by more than 40%in all locations with the biggest changes occurring between 1991 and *** spatial structure around jaguar locations showed that jaguars used areas with mean proportion of natural areas=83.14%(SE=3.72%),mean patch density=1.16 patches/100 ha(SE=0.28 patches/100 ha),mean patch area=616.95 ha(SE=172.89 ha)and mean edge density=705.27 m/ha(SE=182.19 m/ha).We observed strong fragmentation processes in all study locations,which has resulted in the connectivity of jaguar habitat decreasing toproportion of natural vegetation was less than 58.4%(SE=1.3).Conclusions:Assessing fragmentation and connectivity for carnivores within the extent of human-modified la

关键词： Bolivian lowlands Habitat fragmentation Landscape metrics panthera onca Threshold

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DSp应用指南

电子设计技术 1995年第11期 28+30-32页

作者： Markus Levy James p leonard

欢迎阅读1995年DSp指南。本文的目的是向你提供有关通用DSp 芯片的简要而有用的、并且是最新的信息,以便用于你的下一个项目的设计。虽然你的研究可能会超过本指南的范围之外,但它的应用却可用作一个起点:你将从指南的技术分析资料中得... 详细信息

欢迎阅读1995年DSp指南。本文的目的是向你提供有关通用DSp 芯片的简要而有用的、并且是最新的信息,以便用于你的下一个项目的设计。虽然你的研究可能会超过本指南的范围之外,但它的应用却可用作一个起点:你将从指南的技术分析资料中得到益处,并对DSp芯片的件能和标准(技术规范)有一个全面的了解。

关键词： DSp 芯片开发工具

重新设计半主动末制导寻的导弹俯仰稳定控制系统用的计算机辅助法

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系统工程与电子技术 1981年第12期 7-21页

作者： L.S.Shieh ,M.Datta-Barua ,R.E.Yates ,J.p.leonard ,宗有德

过去末制导寻的导弹的不稳定俯仰控制系统是用高阶稳定滤波器来稳定的。这种滤波器采用有源部件。本文提出一种新的主要数据匹配法来重新设计高阶稳定滤波器,以求得一种降阶滤波器。结果降低了器件的成本,提高了可靠性。本文还用一种代... 详细信息

过去末制导寻的导弹的不稳定俯仰控制系统是用高阶稳定滤波器来稳定的。这种滤波器采用有源部件。本文提出一种新的主要数据匹配法来重新设计高阶稳定滤波器,以求得一种降阶滤波器。结果降低了器件的成本,提高了可靠性。本文还用一种代数法来改进重新设计的俯仰控制系统性能。此外,所提出的主要数据匹配法还能用来确定高阶系统的降阶模型。与大多数现有模型简化法不同的是,降阶模型具有原系统精确指定的频率域指标。计算机辅助设计法还可用于设计一般类型的控制系统。

关键词：稳定滤波器重新设计匹配法摄动法传递函数转移函数方程降阶模型末端制导末制导寻的导弹

partial protection by Lipoic Acid Against Carboplantin-induced Ototoxicity in Rats

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Biomedical and Environmental Sciences 2005年第3期18卷 198-206页

作者： KAZIM HUSAIN CRAIG WHITWORTH SATU M. SOMANI leonard p. RYBAK Departments of Surgery Southern Illinois University School of Medicine Springfield IL 62794 USADepartments of Surgery Southern Illinois University School of Medicine Springfield IL 62794 USADepartments of Pharmacology Southern Illinois University School of Medicine Springfield IL 62794 USADepartments of Surgery Southern Illinois University School of Medicine Springfield IL 62794 USA

Objective To investigate the alterations in auditory brainstem evoked responses (ABRs) and the changes of carboplatin-induced ototoxicity in the cochlear oxidant/antioxidant systems and otoprotection by an antioxidant lipoate. Methods Male wistar rats were divided into four groups and treated as follows: 1) vehicle (saline) control, 2) carboplatin (256 mg/kg, i.p.), 3) lipoate (100 mg/kg, i.p.), 4) lipoate + carboplatin. post-treatment ABRs were performed after four days and rats were sacrificed with their cochleae harvested and analyzed. Results Carboplatin significantly elevated ABR threshold above the pretreatment thresholds. Lipoate+carboplatin treated rats showed decreased elevation of hearing threshold. Carboplatin significantly depleted cochlear reduced to oxizized glutathione (GSH/GSSG) ratio, whereas lipoate+carboplatin treatment increased GSH/GSSG ratio. Carboplatin significantly decreased cochlear copper zinc-superoxide dismutase (CuZn-SOD), catalase (CAT), glutathione peroxidase (GSH-px), glutathione reductase (GR) and glutathione-S-transferase (GST) activities and enzyme protein expressions and a significant increase in Mn-SOD activity, protein expression and malondialdehyde (MDA) level. Cochlear antioxidant enzyme activities, enzyme protein expressions and MDA level were partially restored in lipoate+carboplatin treated rats, compared to carboplatin alone. Conclusion Carboplatin-induced ototoxicity is related to impairment of cochlear antioxidant system and otoprotection conferred by lipoate is associated with partial sparing of the cochlear antioxidant defense system.

关键词： Carboplatin Alpha-lipoic acid Ototoxicity Antioxidants Rats

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Study of galvanic corrosion and mechanical joint properties of AZ31B and carbon-fiber–reinforced polymer joined by friction self-piercing riveting

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Journal of Magnesium and Alloys 2022年第2期10卷 434-445页

作者： Yong Chae Lim Jiheon Jun Donovan N.leonard Yuan Li Jian Chen Michael p.Brady Zhili Feng Materials Science and Technology Division Oak Ridge National LaboratoryOne Bethel Valley RoadOak RidgeTN 37831USA

A new testing methodology was developed to quantitively study galvanic corrosion of AZ31B and thermoset carbon-fiber–reinforced polymer spot-joined by a friction self-piercing riveting ***-defined areas of AZ31B in the joint were exposed in 0.1 M NaCl solution over *** galvanic corrosion of AZ31B was observed as exposure time *** measured volume loss was converted into corrosion current that was at least 48 times greater than the corrosion current of AZ31B without galvanic *** percent of the mechanical joint integrity was retained for corroded F-SpR joints to 200 h and then decreased because of the massive volume loss of AZ31B。

关键词： Multi-material joining Carbon fiber–reinforced polymer AZ31B Friction self-piercing riveting Galvanic corrosion Mechanical joint strength

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Susceptibility of field populations of sugarcane borer from non-Bt and Bt maize plants to five individual Cry toxins

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Insect Science 2012年第5期19卷 570-578页

作者： Fangneng Huang Mukti N. Ghimire B. Rogers leonard Yu-Cheng Zhu Graham p. Head Department of Entomology Louisiana State University Agricultural Center Baton Rouge Macon Ridge Research Station Louisiana State University Agricultural Center Winnsboro Louisiana Jamie Whitten Delta States Research Center USDA-ARS Stoneville Mississippi Monsanto Company St. Louis Missouri USA

Sugarcane borer, Diatraea saccharalis （E）, is a major target of transgenic maize expressing Bacillus thuringiensis （Bt） proteins in South America and the US mid- south region. Resistance development in target pest populations is a major threat to the sustainable use of Bt crops. In our field trials in 2009, a significant number of live borers and plant injury fi＇om D. saccharalis were observed in an experimental SmartStaxTM maize line. The objective of this study was to assess the relative susceptibility of two field popula- tions ofD. saccharalis collected from non-Bt and Bt maize plants containing SmartStaxTM traits to five individual Cry proteins. The five Bt proteins included two proteins （Cry 1A. 105 and Cry2Ab2） that were expressed in SmartStaxTM maize plants and three other common Bt proteins （Cry 1Aa, Cry 1Ab and Cry l Ac） that were not produced in SmartStaxTM. Larval mortality and growth inhibition on Bt diet of the fourth generation after field collections were evaluated 7 days after release of neonates on the diet surface. The laboratory bioassays showed that 50% lethal concentration （LCs0） values for CrylA. 105 and Cry2Ab2 for the population originated from Bt plants were 3.55- and 1.34-fold greater, respectively, than those of the population collected from non-Bt plants. In contrast, relative to the popula- tion from non-Bt plants, the LCs0 of the population sampled from Bt plants were 3.85-, 2.5- and 1.64-fold more sensitive to CrylAa, CrylAb and CrylAc, respectively. The re- sults did not provide clear evidence to conclude that the observed field survival of D. saccharalis on Bt plants was associated with increased levels of resistance.

关键词： Bacillus thuringiensis maize stalk borer susceptibility transgenic crops

Targeted prostate biopsy using magnetic resonance imaging-ultrasound fusion

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Asian Journal of Andrology 2015年第6期17卷 870-873,I0006页

作者： Nathan Bockholt leonard S Marks Department of Urology David Geflen School of Medicine at UCLA Los Angeles CA USA.

prostate cancer is the second most common cancer among men worldwide, with an estimated 1.1 million new diagnoses and over 300,000 deaths reported in 2012 by the World Health Organization. A recent 5-year prevalence of the disease was nearly four million, far exceeding all other malignancies in men. Because of these numbers, efforts to improve early detection, accurate assessment of disease burden, and appropriate treatment options are important public-health priorities. However, the basic tool for diagnosis, transrectal ultrasound （TRUS） guided biopsy, is flawed by failure to detect many serious cancers （〉30% false negative rate） and over-detection of nonserious cancers. Multiparametric magnetic resonance imaging （mpMRI） of the prostate empowers the clinician to identify tumors that would otherwise be missed by conventional techniques and to record the precise locations of positive cores through targeted biopsy using MRI-ultrasound （MRI-US） fusion. As mpMRI advances and the level of experience for the user grows, the correlation between the level of suspicion for a prostate lesion and the MRI-US fusion targeted biopsy revealing malignancy improves. Consequently, the concordance among the targeted biopsy and surgical pathology rises. This in turn, allows the patient and provider to be confident that the therapeutic plan decided upon is representative of the true disease state.

关键词： Targeted biopsy fusion

Regulatory T cells in skin regeneration and wound healing

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Military Medical Research 2024年第5期11卷 663-685页

作者： Samuel Knoedler leonard Knoedler Martin Kauke-Navarro Yuval Rinkevich Gabriel Hundeshagen Leila Harhaus Ulrich Kneser Bohdan pomahac Dennis p.Orgill Adriana C.panayi Division of plastic Surgery Department of SurgeryBrigham and Women’s HospitalHarvard Medical SchoolBostonMA02115USA Division of plastic Surgery Department of SurgeryYale New Haven HospitalYale School of MedicineNew HavenCT06510USA Institute of Regenerative Biology and Medicine Helmholtz Zentrum MünchenMunich85764Germany Department of Hand Plastic and Reconstructive SurgeryMicrosurgeryBurn Trauma CenterBG Trauma Center LudwigshafenUniversity of HeidelbergLudwigshafen67071Germany

As the body’s integumentary system,the skin is vulnerable to *** subsequent wound healing processes aim to restore dermal and epidermal integrity and *** this end,multiple tissue-resident cells and recruited immune cells cooperate to efficiently repair the injured *** temporally-and spatially-coordinated interplay necessitates tight regulation to prevent collateral damage such as overshooting immune responses and excessive *** this context,regulatory T cells(Tregs)hold a key role in balancing immune homeostasis and mediating cutaneous wound healing.A comprehensive understanding of Tregs’multifaceted field of activity may help decipher wound pathologies and,ultimately,establish new treatment ***,we review the role of Tregs in orchestrating the regeneration of skin adnexa and catalyzing healthy wound ***,we discuss how Tregs operate during fibrosis,keloidosis,and scarring.

关键词： Regulatory T cells(Tregs) Wound healing Wound repair Skin injury Skin regeneration

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Sustained-release drug delivery systems for the treatment of glaucoma

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International Journal of Ophthalmology(English edition) 2021年第1期14卷 148-159页

作者： Natasha p.Kesav Cara E.Capitena Young Monica K.Ertel leonard K.Seibold Malik Y.Kahook Department of Ophthalmology University Hospitals Cleveland Medical CenterClevelandOH 44106USA Department of Ophthalmology University of Colorado School of MedicineCO 80045USA

Glaucoma,a leading cause of irreversible blindness,affects more than 64 million people worldwide and is expected to grow in number due to the aging global population and enhanced methods of *** topical therapies are often effective when used as prescribed,the drawbacks of current medical management methods include poor patient adherence,local and systemic side effects,and in some cases,limited therapeutic *** ocular drug delivery platforms promise to deliver differentiated drug formulations with targeted delivery leveraging patient-independent *** platforms are in various stages of development with promising pre-clinical and clinical *** Bimatoprost Sustained Release (SR) intracameral implant was approved in the United States in March of 2020,making it the first long-term injectable therapy available for the treatment of *** review aims to provide an update on novel sustained release drug delivery systems that are available today as well as those that might be commercialized in coming years.

关键词： glaucoma drug delivery sustained release