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空中英语教室（高级版．彭蒙惠英语） 2013年第5期 26-26,45页

作者： by peter frost and melissa harris

Management of ejaculatory disorders in infertile men

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Asian Journal of Andrology 2012年第4期14卷 525-529页

作者： Yagil Barazani peter J Stahl harris M Nagler Doron S Stember Beth Israel Medical Center and the Albert Einstein College of Medicine of Yeshiva University New YorkNew York 10003USA Department of Urology Columbia University Medical CenterNew YorkNY 10003USA

Ejaculatory dysfunction is a highly prevalent clinical condition that may be classified along a continuum that ranges from premature ejaculation （PE）, through retarded or delayed ejaculation （DE）, to complete anejaculation （AE）. Retrograde ejaculation （RE） represents a distinct entity in which ejaculate is expelled either partially or completely into the bladder. While DE and PE are significant sources of sexual dissatisfaction among men and their partners, patients with these disorders retain normal fertility in most cases. Conversely, men with AE and RE are unable to deliver sperm into the female genital tract and are therefore rendered subfertile. Therefore, in reviewing ejaculatory disorders as they relate to fertility, this paper will primarily focus on the diagnosis and management of AE and RE. Physiology, diagnostic strategies, pharmacological treatments, and procedural interventions relevant to AE and RE are discussed.

关键词： anejaculation delayed ejaculation ejaculatory dysfunction electroejaculation penile vibratory stimulation prematureejaculation retrograde ejaculation

Role of Raman spectroscopy and surface enhanced Raman spectroscopy in colorectal cancer

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World Journal of Gastrointestinal Oncology 2016年第5期8卷 427-438页

作者： Cerys A Jenkins Paul D Lewis peter R Dunstan Dean A harris Swansea University Medical School Swansea University Department of Physics College of ScienceCenter for NanohealthSwansea University Department of Colorectal Surgery Singleton Hospital

Colorectal cancer(CRC) is the fourth most commoncancer in the United Kingdom and is the second largest cause of cancer related death in the United Kingdom after lung *** in the United Kingdom there is not a diagnostic test that has sufficient differentiation between patients with cancer and those without cancer so the current referral system relies on symptomatic presentation in a primary care *** spectroscopy and surface enhanced Raman spectroscopy(SERS) are forms of vibrational spectroscopy that offer a nondestructive method to gain molecular information about biological *** techniques offer a wide range of applications from in vivo or in vitro diagnostics using endoscopic probes,to the use of micro-spectrometers for analysis of *** techniques have the potential to detect molecular changes prior to any morphological changes occurring in the tissue and therefore could offer many possibilities to aid the detection of *** purpose of this review is to look at the current state of diagnostic technology in the United *** development of Raman spectroscopy and SERS in clinical applications relation for CRC will then be ***,future areas of research of Raman/SERS as a clinical tool for the diagnosis of CRC are also discussed.

关键词： Detection Colorectal cancer Spectroscopy Raman Surface enhanced Raman Spectroscopy

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矿物资源的价值

轻金属 1991年第8期 4-10页

作者： peter harris 冯秀纯

矿物资源真的有价值么?这正是关于矿藏价值的一次讨论会上,所收到的一份稿件的题目。关于矿藏的价值,自从前民主德国有迹象将其拥有的矿藏看成是新建公司的资产以来,现在已是一个热门话题。

关键词：矿床价值

Advancing proteomics and machine learning in the clinic:an editorial on“Noninvasive proteomic biomarkers for alcohol-related liver disease”

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Hepatobiliary Surgery and Nutrition 2022年第5期11卷 762-765页

作者： Courtney D.McGinnis Brenton I.M.Graham peter S.harris Kristofer S.Fritz Skaggs School of Pharmacy and Pharmaceutical Sciences University of Colorado Anschutz Medical CampusAuroraCOUSA

Alcohol-associated liver disease(ALD)is increasingly prevalent throughout the world(1).It remains the leading cause of liver-related morbidity and mortality worldwide and contributes to approximately 6%of global deaths(2).ALD encompasses a wide range of hepatic pathologies,including steatosis,steatohepatitis,fibrosis,and cirrhosis(3).Given the severe lack of therapeutic interventions available to reverse the progression of ALD,it is currently the leading indication for liver transplantation(4).Advancements within the field are needed to identify diagnostic biomarkers for early detection and to develop therapeutics to ameliorate hepatic dysfunction and pathologies associated with ALD.

关键词： hepatic liver mortality

On (t, r) Broadcast Domination of Directed Graphs

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Open Journal of Discrete Mathematics 2022年第3期12卷 78-100页

作者： Pamela E. harris peter Hollander Erik Insko Department of Mathematics and Statistics Williams College Williamstown MA USA Department of Mathematics Florida Gulf Coast University Fort Myers FL USA

A dominating set of a graph G is a set of vertices that contains at least one endpoint of every edge on the graph. The domination number of G is the order of a minimum dominating set of G. The (t, r) broadcast domination is a generalization of domination in which a set of broadcasting vertices emits signals of strength t that decrease by 1 as they traverse each edge, and we require that every vertex in the graph receives a cumulative signal of at least r from its set of broadcasting neighbors. In this paper, we extend the study of (t, r) broadcast domination to directed graphs. Our main result explores the interval of values obtained by considering the directed (t, r) broadcast domination numbers of all orientations of a graph G. In particular, we prove that in the cases r = 1 and (t, r) = (2, 2), for every integer value in this interval, there exists an orientation of G which has directed (t, r) broadcast domination number equal to that value. We also investigate directed (t, r) broadcast domination on the finite grid graph, the star graph, the infinite grid graph, and the infinite triangular lattice graph. We conclude with some directions for future study.

关键词： Directed Domination Directed Broadcasts Finite and Infinite Directed Grid Graphs

Hardware Architecture of Polyphase Filter Banks Performing Embedded Resampling for Software-Defined Radio Front-Ends

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ZTE Communications 2012年第1期10卷 54-62,70页

作者： Mehmood Awan Yannick Le Moullec peter Koch Fred harris Technology Platforms Section Dept. of Electronic Systems Aalborg University Dept. of Electrical & Computer Engineering San Diego State University

In this paper, we describe resourceefficient hardware architectures for softwaredefined radio （SDR） frontends. These architectures are made efficient by using a polyphase channelizer that performs arbitrary sample rate changes, frequency selection, and bandwidth control. We discuss area, time, and power optimization for field programmable gate array （FPGA） based architectures in an Mpath polyphase filter bank with modified Npath polyphase filter. Such systems allow resampling by arbitrary ratios while simultaneously performing baseband aliasing from center frequencies at Nyquist zones that are not multiples of the output sample rate. A nonmaximally decimated polyphase filter bank, where the number of data loads is not equal to the number of M subfilters, processes M subfilters in a time period that is either less than or greater than the Mdataload ＇ s time period. We present a loadprocess architecture （LPA） and a runtime architecture （RA）（based on serial polyphase structure） which have different scheduling. In LPA, Nsubfilters are loaded, and then M subfilters are processed at a clock rate that is a multiple of the input data rate. This is necessary to meet the output time constraint of the down-sampled data. In RA, Msubfilters processes are efficiently scheduled within Ndataload time while simultaneously loading N subfilters. This requires reduced clock rates compared with LPA, and potentially less power is consumed. A polyphase filter bank that uses different resampling factors for maximally decimated, underdecimated, overdecimated, and combined upand downsampled scenarios is used as a case study, and an analysis of area, time, and power for their FPGA architectures is given. For resourceoptimized SDR frontends, RA is superior for reducing operating clock rates and dynamic power consumption. RA is also superior for reducing area resources, except when indices are prestored in LUTs.

关键词： SDR FPGA Digital Frontends Polyphase Filter Bank Embedded Resampling

Polyphase Filter Banks for Embedded Sample Rate Changes in Digital Radio Front-Ends

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ZTE Communications 2011年第4期9卷 3-9页

作者： Mehmood Awan Yannick Le Moullec peter Koch Fred harris Technology Platforms Section Dept. of Electronic Systems Aalborg University Denmark Dept. of Electrical & Computer Engineering San Diego State UniversityCA USA

This paper presents efficient processing engines for software-defined radio （SDR） front-ends. These engines, based on a polyphase channelizer, perform arbitrary sample-rate changes, frequency selection, and bandwidth control. This paper presents an M-path polyphase filter bank based on a modified N-path polyphase filter. Such a system allows resampling by arbitrary ratios while performing baseband aliasing from center frequencies at Nyquist zones that are not multiples of the output sample rate. This resampling technique is based on sliding cyclic data load interacting with cyclic-shifted coefficients. A non-maximally-decimated polyphase filterbank （where the number of data loads is not equal to the number of M subfilters） processes M subfilters in a time period that is less than or greater than the M data loads. A polyphase filter bank with five different resampling modes is used as a case study for embedded resamp/ing in SDR front-ends. These modes are （i） maximally decimated, （ii） Under-decimated, （iii） over-decimated, and combined up- and down-sampling with （iv） single stride length, and （v） multiple stride lengths. These modes can be used to obtain any required rational sampling rate change in an SDR front-end based on a polyphase channelizer. They can also be used for translation to and from arbitrary center frequencies that are unrelated to the output sample rates.

关键词： SDR digital front-ends polyphase filter bank embedded resampling

Biochemical and Molecular Epidemiology of Cancer

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Biomedical and Environmental Sciences 1991年第1期4卷 73-92页

作者： HARUHIKO SUGIMURA AINSLEY WESTON NEIL E.CAPORASO peter G.SHIELDS ELISE D.BOWMAN ROBERT A.METCALF CURTIS C.harris Laboratory of Human Carcinogenesis Laboratory of Human CarcinogenesisEnvironmental Epidemiology Branch National Cancer Institute National Institutes of HealthLaboratory of Human CarcinogenesisLaboratory of Human CarcinogenesisLaboratory of Human CarcinogenesisLaboratory of Human Carcinogenesis Rockville Maryland 20892

Examples of practical approaches to molecular epidemiology of human cancer are described. Biomarkers of carcinogen exposure or inherited host factors for cancer susceptibility are discussed. Major advances have been made in the detection of carcinogen-macromolecular adducts through the use of high performance liquid chromatography, immunoaffinity chromatography, the 32P-postlabeling assay, enzyme immunoassays, gas chromatography/mass spectroscopy and synchronous spectrophotofluorimetry. The polycyclic aromatic hydrocarbon- DNA adducts are the most extensively studied in this field and together with antibodies to these adducts found in human serum, they have become useful indicators of exposure to carcinogens. Assays for various kinds of alky 1-DNA adducts have also been developed and the presence of these adducts have been documented in human tissues. Carcinogen-protein adducts have proven to be useful molecular dosimeters of carcinogen exposure. For example, 4-aminobiphenyl hemoglobin adducts are highly correlated with exposure to tobacco smoke. The study of the molecular aspects of interindividual differences in the metabolism and activation of xenobiotics and other genetic markers [DNA-restriction fragment length polymorphisms (RFLPs), mutations, and functional loss of specific genes in carcinogenesis] is an emerging new field that is discussed in the context of genetic susceptibility to cancer. The cytochrome P450 phenotypes and acetylation phenotype are examples of genetic markers that indicate an individual's potential for metabolism of exogenous substances. Further, inherited genetic polymorphic markers, e.g., DNA-RFLPs at protooncogene loci (HRAS-1 and L-myc) have been examined in a case-control study of lung cancer. Data concerning mutations of protooncogenes (H-, K-, and N-RAS) and tumor suppressor genes (retinoblastoma and p53 genes) in various common cancers are providing evidence of multiple genetic lesions that occur during the multistage process of ca

关键词： gene DNA Biochemical and Molecular Epidemiology of Cancer

The tropical-subtropical evergreen forest transition in East Asia:An exploration

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Plant Diversity 2020年第4期42卷 255-280页

作者： peter Ashton Hua Zhu Arnold Arboretum Harvard UniversityRoyal Botanic GardensKewUK Center for Integrative Biology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYunnanPR China

The transition from tropical to subtropical(warm temperate)evergreen forests is more clearly apparent in East Asia,fromNepal to the western Pacific coast,than elsewhere in the *** review the nature of this transition and hypothesize the physical,ultimately climatic,factors thatmay maintain it,with a special focus on how the increasing instability and warming of climates will affect these forests.A primary climatic mediator of the transition is proposed,thereby offering a testable hypothesis for the climateeforest transition *** is known of this transition is summarized in context of the primary climatic mediators of elevational zonation of forest formations in equatorial Asia to the tree line,in the Himalaya at the India-Indo-Burma northern tropical margin,and as both elevational and latitudinal zonation in southern *** secondary edaphic and other physical changes are described for the Himalaya,and hypothesized for southern *** forest ecotones are seen to be primarily defined by tree floristic change,on which account changes in structure and physiognomy are *** montane tropical-subtropical transition in the Himalaya is narrowand observed to correlate with an as yet ill-defined frost line.A distinct tropical-subtropical transition forest is recognized in the southwest *** is a total change in canopy species at the Himalayan ecotone,but subcanopy tropical species persist along an elevational decline of c.400 *** latitudinal transition in South China is analogous,but here the tropical subcanopy component extends north over ten degrees latitude,albeit in *** tropical-subtropical transition is uniquely clear in East Asia because here alone a tropical wet summer-dry winter monsoon extends to 35north latitude,encompassing the subtropical evergreen forest,whereas subtropical evergreen forests elsewhere exist under drier temperate summer climate regimes.

关键词： Tropical Subtropical Forest transition Ecotone East Asia