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Comparison of the Birds Point-New Madrid Floodway, Mississippi River and the Yolo Bypass, Sacramento River

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Journal of Earth Science 2016年第1期27卷 47-54页

作者： brad Walker Missouri Coalition for the Environment St. Louis MO 63118 USA

The Birds Point-New Madrid Floodway（BP-NMF） and the Yolo Bypass, located on the Mississippi and Sacramento rivers, respectively, are agriculture areas that were once each part of vast wetlands but are now intermittently used for flood control. Here the similarity stops, the BP-NMF has been used to convey floodwaters only twice in nearly 80 years, while the Yolo Bypass is used for this purpose on average every other year. The consequences are greatly different. In 2011, the BP-NMF was activated through the explosive detonation of the ＇fuse plug＂ portion of its levees, resulting in elevated property and economic damages, crop losses, and litigation. High-energy flows following the opening of the BP-NMF scour coarse sediment in the vicinity of the opening of the BP-NMF and deposit this material within the floodway, including on agricultural fields. In general the environment of much of the BP-NMF provides poor wildlife habitat. In contrast, the routine operation of Yolo Bypass is expected, avoids damage and litigation, supplies organic-rich sediment to fields, and provides good wildlife habitat. The difference between the two systems is attributed to a better approximation of natural conditions on the Yolo Bypass.

关键词： New Madrid Floodway Yolo Bypass flood control

SHOULD YOU PUT YOUR ENERGY INTO GREEN ROOFS TO REDUCE ENERGY CONSUMPTION IN YOUR BUILDING

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Journal of Green Building 2008年第2期3卷 26-40页

作者： brad Bass North American Green Roof Research Committee Network Adaptation&Impacts Research Division Environment Canada at the University of Toronto

INTRODUCTION Green roofs are touted as an environmental technology for urban areas due to their many benefi ts(Lundholm et al.2008).Although the design and the benefi ts have been reported in many reports and articles,they are reviewed here for those who are unfamiliar with this *** roofs,or more formally,green roof infrastructure,is a technology that allows for the growth of vegetation on a roof while protecting the building envelope from leakage and root penetration.A green roof is more than a layer of soil piled on the roof,planted in the way that you might plant a *** technology consists of multiple layers that include the plants and growing medium or substrate,but also a drainage layer for storing water that was not used by the plants and a waterproof,root-repellent membrane(Figure 1).

关键词： Figure planted formally

From filaments to function: The role of the plant actin cytoskeleton in pathogen perception,signaling and immunity

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Journal of Integrative Plant Biology 2016年第4期58卷 299-311页

作者： Katie Porter brad Day Graduate Program in Cell and Molecular Biology Michigan State University Department of Plant Soil and Microbial Sciences Michigan State University Graduate Program in Genetics Michigan State University

The eukaryotic actin cytoskeleton is required for numerous cellular processes, including cell shape, development and movement, gene expression and signal transduction, and response to biotic and abiotic stress. In recent years,research in both plants and animal systems have described a function for actin as the ideal surveillance platform, linking the function and activity of primary physiological processes to the immune system. In this review, we will highlight recent advances that have defined the regulation and breadth of function of the actin cytoskeleton as a network required for defense signaling following pathogen infection. Coupled with an overview of recent work demonstrating specific targeting of the plant actin cytoskeleton by a diversity of pathogens,including bacteria, fungi and viruses, we will highlight the importance of actin as a key signaling hub in plants, one that mediates surveillance of cellular homeostasis and the activation of specific signaling responses following pathogen perception. B4 ased on the studies highlighted herein, we propose a working model that posits changes in actin filament organization is in and of itself a highly specific signal, which induces, regulates and physically directs stimulus-specific signaling processes, most importantly, those associated with response to pathogens.

关键词： Actin cytoskeleton immunity pathogen plant Pseudomonas syringae surveillance

The BK channel:a vital link between cellular calcium and electrical signaling

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Protein & Cell 2012年第12期3卷 883-892页

作者： brad S.Rothberg Department of Biochemistry Temple University School of MedicinePhiladelphiaPA 19140USA

Large-conductance Ca^(2+)-activated K+channels(BK channels)constitute an key physiological link between cellular Ca^(2+) signaling and electrical signaling at the plasma *** these channels are critical to the control of action potential firing and neurotrans-mitter release in several types of neurons,as well as the dynamic control of smooth muscle tone in resis-tance arteries,airway,and *** advances in our understanding of K^(+) channel structure and function have led to new insight toward the molecular mecha-nisms of opening and closing(gating)of these *** we will focus on mechanisms of BK channel gating by Ca^(2+),transmembrane voltage,and auxiliary subunit proteins.

关键词： RCK domain voltage sensor blood pressure leucine-rich repeat-containing(LRRC)protein

Development of a PWM Precision Spraying Controller for Unmanned Aerial Vehicles

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Journal of Bionic Engineering 2010年第3期7卷 276-283页

作者： W.Clint Hoffmann brad Fritz USDA-ARS College Station

This paper presents a new Pulse Width Modulation (PWM) controller for Unmanned Aerial Vehicle (UAV) precisionsprayer for agriculture using a TL494 fixed-frequency pulse width modulator together with a data acquisition board and developedsoftware. An UAV can be remotely controlled or flown autonomously by pre-programmed flight plans. The PWMcontroller was implemented through the guidance system on the UAV with control commands sent between the UAV helicopterand the ground control station via a wireless telemetry system. The PWM controller was tested and validated using LabVIEW8.2. Several analyses were performed in a laboratory to test different control signals. The results show that the PWM controllerhas promise as a higher precision technique for spray applications, which will improve efficiency of pesticide application,especially in crop production areas.

关键词： PWM controller TL494 precision spraying UAV

Discovery of nigral dopaminergic neurogenesis in adult mice

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Neural Regeneration Research 2016年第6期11卷 878-881页

作者： brad E.Morrison Department of Biological Sciences Boise State University Biomolecular Ph.D.Program Boise State University

Parkinson＇s disease is characterized by the loss of dopaminergic neurons in the substantia nigra. As a result, intensive efforts have focused upon mechanisms that facilitate the death of mature dopaminergic neurons. Unfortunately, these efforts have been unsuccessful in providing an effective treatment to address neurodegeneration in this disease. Therefore, alternative theories of pathogenesis are being explored. Adult neurogenesis of dopaminergic neurons is an attractive concept that would provide a possible mechanism of neurodegeneration as well as offer an endogenous means to replenish affected neurons. To determine whether dopaminergic neurons experience neurogenesis in adult mice we developed a novel cell lineage tracing model that permitted detection of neurogenesis without many of the issues associated with popular techniques. Remarkably, we discovered that dopaminergic neurons are replenished in adult mice by Nestin＋/Sox2- progenitor cells. What＇s more, the rate of neurogenesis is similar to the rate of dopaminergic neuron loss reported using a chronic, systemic inflammatory response mouse model. This observation may indicate that neuron loss in Parkinson＇s disease results from inhibition of neurogenesis.

关键词： substantia nigra progenitor tamoxifen pathogenesis endogenous mature attractive hydroxylase providing

Acute and long-term changes in blood flow after ischemic stroke:challenges and opportunities

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Neural Regeneration Research 2023年第4期18卷 799-800页

作者： Dino Premilovac brad A.Sutherland Tasmanian School of Medicine College of Health and MedicineUniversity of TasmaniaHobartTASAustralia

The brain has a high metabolic rate and consumes approximately 20% of the total energy in the body at any given time. Although it requires a large amount of energy to function, the brain cannot store significant amounts of energy making it exquisitely dependent on constant nutrient supply via blood flow. When blood flow to the brain is impaired, such as during stroke, there are rapid and severe consequences for the neurons that depend on this constant energy supply.

关键词： impaired flow Acute

Uncover the Peer Distribution in BitTorrent

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Tsinghua Science and Technology 2012年第1期17卷 17-28页

作者： brad Rougeau Mea Wang Mea Wang Department of Computer Science University of Calgary Calgary AB T2N 1N4 Canada

Peer-to-peer traffic constitutes more than 60% of today＇s Internet traffic, resulting in high band- width cost for ISPs. Recent efforts have been made to modify BitTorrent clients to reduce inter-ISP traffic. Although the results have been encouraging, recent research also reveals that global adaptation of such an approach may harm the download time as there is no clear evidence of persistent clustering in all ISPs. To this end, many large scale measurements on BitTorrent topology have been conducted by analyzing differ- ent snapshots of the BitTorrent network. However, the analysis overlooked the download time, the actual contributions of peers, and the distribution of peers throughout the file download period since the snapshots were obtained by querying the tracker for tP addresses of peers at a certain time. In this paper, we seek to understand to what extent the distribution of peers in BitTorrent relates to their contributions in data swarm- ing and transmission rates by studying real BitTorrent download traces. In order to present an unbiased view, we collected the traces from over 100 different files, including books （in different languages）, music （in different languages）, movies, and software （for different operating systems）. The file size ranges from 4 MB to 4 GB. We also compared traces from a regular BitTorrent client with an ISP-friendly BitTorrent client to examine the actual impact of an ISP-friendly algorithm on download time and peer contributions. Our major findings include that distance has no effect on the download rate in general, seeds or lechers cannot always be found within the same ISP, and a torrent can only benefit from an ISP-friendly approach in certain situa- tions. Suggestions are given on how BitTorrent clients can be more ISP-friendly without sacrificing download rate.

关键词： peer-to-peer BitTorrent measurement ISP traffic localization

Harnessing the stem cell properties of pericytes to repair the brain

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Neural Regeneration Research 2020年第6期15卷 1021-1022页

作者： Jo-Maree Courtney brad A.Sutherland School of Medicine College of Health and Medicine University of Tasmania

Over the last ten years or so,it has become apparent that pericytes have the potential to differentiate into other cell types which may help in the repair and regeneration of tissue after *** fact,pericytes have been described as a precursor to mesenchymal stem *** location at the interface between the microvasculature and the brain parenchyma means they are ideally positioned to initiate repair and regeneration in response to various *** this perspective,we will highlight how pericytes have stem cell potential alongside their role in regulating processes,such as angiogenesis and inflammation,and discuss how pericytes could be harnessed to promote tissue repair in the brain(Figure 1).

关键词： pericyte inflammation Figure