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Neuromelanin,one of the most overlooked molecules in modern medicine,is not a spectator

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Neural Regeneration Research 2017年第3期12卷 372-375页

作者： robert l.Haining Cindy Achat-Mendes Georgia Gwinnett College 1000 University Center LnSchool of Science and TechnologyLawrencevilleGAUSA

The loss of pigmented neurons from the human brain has long been the hallmark of Parkinson＇s disease（PD）.Neuromelanin（NM） in the pre-synaptic terminal of dopamine neurons is emerging as a primary player in the etiology of neurodegenerative disorders including *** mini-review discusses the interactions between neuromelanin and different molecules in the synaptic terminal and describes how these interactions might affect neurodegenerative disorders including *** can reversibly bind and interact with amine containing neurotoxins,e.g.,MPTP,to augment their actions in the terminal,eventually leading to the instability and degeneration of melanin-containing neurons due to oxidative stress and mitochondrial *** particular,neuromelanin appears to confer susceptibility to chemical toxicity by providing a large sink of iron-bound,heme-like structures in a pi-conjugated system,a system seemingly purposed to allow for stabilizing interactions including pi-stacking as well as ligand binding to *** the progressive accumulation of NM with age corresponding with an apparent decrease in dopamine synthetic pathways,the immediate question of whether NM is also capable of binding dopamine,the primary functional monoamine utilized in this cell,should be *** the rather glaring implications of this finding,this idea appears not to have been adequately *** such,we postulate on potential mechanisms by which dopamine might dissociate from neuromelanin and the implications of such a reversible ***,if neuromelanin is able to sequester and release dopamine in membrane bound vesicles,this intracellular pre-synaptic mechanism could be the basis for a form of chemical memory in dopamine neurons.

关键词： dopamine dopamine storage Parkinson's disease neurodegeneration neuromelanin neurotoxicity

landform type mediates compositional change in a hurricane-disturbed subtropical forest

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Ecological Processes 2020年第1期9卷 292-304页

作者： robert l.Spicer Ariel Elugo Nathan Ruhl Department of Biological Science Rowan UniversityGlassboroNJ 08028USA International Institute of Tropical Forestry United States Department of Agriculture Forest ServiceJardín Botánico SurRío PiedrasPRUSA

Background:Categorization of topographical features into landform type is a long-standing method for understanding physiographic patterns in the *** in forest composition between landform types are driven primarily by concurrent differences in soil composition and moisture,but also disturbance *** studies have focused on the interaction between fire disturbance,succession,and landforms,but the effects of hurricane disturbance on compositional differences between landforms are poorly *** the study presented here,we assess compositional and structural differences between landform types in the tree community of a young sub-tropical forest that is frequently subjected to ***,we ask whether the tree community(1)changed structurally over the study period,(2)experienced compositional change over the study period,(3)is compositionally different between landform types,and(4)exhibits compositional change mediated by landform ***:The tree community experienced significant structural change over the course of our study,but compositional change was only significant for some ***:Despite large-scale,intense,and frequent hurricane disturbance to our study system,compositional change in the tree community was localized and only significant for some landform types.

关键词： Hurricane Forest Community Composition Change Succession landform

Update on obesity surgery

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World Journal of Gastroenterology 2006年第20期12卷 3196-3203页

作者： Dan Eisenberg Andrew J Duffy robert l Bell Department of Surgery Yale University School of Medicine 40 Temple St. Suite 3A New HavenCT 06510United States

The prevalence of obesity in the United States has reached epidemic proportions. With more than 30 million Americans clinically obese, the younger population has also been affected. Surgical therapy should be offered to the severely obese patient who is refractory to nonsurgical therapy, as established by the 1991 NIH Consensus Conference on Gastrointestinal Surgery for Severe Obesity. Surgery is currently the most effective therapy for weight loss. It is far more effective than any other treatment modality, both in terms of the amount of weight loss and in terms of durability in maintaining weight loss.

关键词： Obesity Gastrointestinal surgery Roux-Y gastric bypass

Different characteristics of chronic dibutyltin dichloride-induced pancreatitis and cholangitis in mouse and rat

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Hepatobiliary & Pancreatic Diseases International 2020年第2期19卷 169-174页

作者： Friederike lütt luise Ehlers Horst Nizze robert Jaster Department of Medicine II Division of GastroenterologyRostock University Medical CenterE.-Heydemann-Str.618057 RostockGermany Institute of Pathology Rostock University Medical CenterStrempelstraβ1418057 RostockGermany

Background:Current animal models of chronic pancreatitis(CP)often provide only limited pathophysio-logical insights since they incompletely reflect the human *** induced by injection of dibutyltin dichloride(DBTC-pancreatitis)shares with human CP the important feature of extended fibrosis and would be an even more attractive model if it could be transferred from rats to mice,as recently sug-gested in the context of combined ethanol and DBTC *** study aimed to evaluate the effects of DBTC in pancreas and liver of C57Bl/6 mice,a strain commonly used to engineer genetic mouse ***:C57Bl/6 mice and lewis rats were exposed to variable doses of *** an investigation period of up to 4 weeks,laboratory findings and histopathological changes of pancreas and liver were ***:Chronic DBTC-pancreatitis in rats was characterized by acinar cell damage,ductal changes,fi-brosis,and inflammatory cell *** treated with DBTC at 6–8 mg/kg body weight,the standard doses in rats,showed transient increases of lipase activities but no morphological signs of chronic DBTC-pancreatitis 4 weeks after injection of the *** doses of 10–12 mg/kg DBTC were intolerable due to their high *** contrast,mice and rats presented with a similar histopathology of the liver that can be characterized as a chronic-proliferative DBTC-cholangitis with predominating damage and proliferation of the small bile ducts as well as secondary portal inflammatory cell infiltrates and a begin-ning portal ***:The DBTC-model cannot be transferred from rats to C57Bl/6 mice with respect to chronic DBTC-pancreatitis,but might be of interest to study DBTC-cholangitis in both species.

关键词： Animal models Cholangitis Pancreatitis

Evolution of surgical skills training

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World Journal of Gastroenterology 2006年第20期12卷 3219-3224页

作者： Kurt E roberts robert l Bell Andrew J Duffy Department of Surgery Yale University School of Medicine 40 Temple StreetSuite 3ANew HavenCT 06510United Staets

Surgical training is changing： one hundred years of tradition is being challenged by legal and ethical concerns for patient safety, work hours restrictions, the cost of operating room time, and complications. Surgical simulation and skills training offers an opportunity to teach and practice advanced skills outside of the operating room environment before attempting them on living patients. Simulation training can be as straight forward as using real instruments and video equipment to manipulate simulated ＂tissue＂ in a box trainer. More advanced, virtual reality simulators are now available and ready for widespread use. Early systems have demonstrated their effectiveness and discriminative ability. Newer systems enable the development of comprehensive curricula and full procedural simulations. The Accreditation Council of Graduate Medical Education＇s （ACGME） has mandated the development of novel methods of training and evaluation. Surgical organizations are calling for methods to ensure the maintenance of skills, advance surgical training, and to credential surgeons as technically competent. Simulators in their current form have been demonstrated to improve the operating room performance of surgical residents. Development of standardized training curricula remains an urgent and important agenda, particularly for minimal invasive surgery. An innovative and progressive approach, borrowing experiences from the field of aviation, can provide the foundation for the next century of surgical training, ensuring the quality of the product. As the technology develops, the way we practice will continue to evolve, to the benefit of physicians and patients.

关键词： Surgery Training Certification Skills Simulation Curriculum

Controversies in the treatment of gastroesophageal reflux and achalasia

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World Journal of Gastroenterology 2006年第20期12卷 3155-3161页

作者： Kurt E roberts Andrew J Duffy robert l Bell Department of Surgery Yale University School of Medicine 40 Temple St. Suite 3 ANew HavenCT 06510United States

The immense success of laparoscopic surgery as an effective treatment of gastroesophageal reflux disease （GERD） and achalasia has established minimal invasive surgery as the gold standard for these two conditions with lower morbidity and mortality, shorter hospital stay, faster convalescence, and less postoperative pain. One controversy in the treatment of GERD evolves around laparoscopic antireflux surgery （lAP, S） as the preferred treatmerit for Barrett＇s esophagus and the procedure＇s potential to reduce the risk of adenocarcinoma of the esophagus. GERD has also been associated with respiratory symptoms, asthma and laryngeal injury, and a second controversy prompts discussions about whether total or partial fundoplication is the more appropriate treatment for GERD. A new and promising alternative in the treatment of GERD is endoluminal therapy. Three types of this new treatment option will be discussed： radiofrequency energy delivered to the lower esophageal sphincter, the creation of a mechanical barrier at the gastroesophageal junction, and the direct endoscopic tightening of the lower esophageal sphincter. laparoscopic surgery is discussed not only as a very effective treatment for GERD but also as permanent cure for achalasia. This review analyzes the three most important treatment options for achalasia： medications, pneumatic dilatation, and surgical therapy. Medications as the only true non-invasive option in the treatment of achalasia are not as effective as lAPS because of their short half-life and variable absorption due to the poor esophageal emptying. The second treatment option, pneumatic dilatation, involves the stretching of the lower esophagus and is still considered the most effective nonsurgical treatment for achalasia. Finally, surgical therapy for achalasia and the two major controversies concerning this laparoscopic treatment are discussed. The first involves the extent to which the myotomy is extended onto the stomach, and the second concer

关键词： Gastroesophageal reflux disease Nissen Toupet Fundoplication Achalasia Heller myotomy

Developmental ecology of the American horseshoe crab limulus polyphemus

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Current Zoology 2010年第5期56卷 550-562页

作者： Mark l.BOTTON Richard A.TANKERSlEY robert E.lOVElAND Department of Natural Sciences Fordham University Department of Biological Sciences Florida Institute of Technology Department of Ecology Evolution and Natural Resources Rutgers University

During spawning events, horseshoe crab eggs are released from the female＇s oviducts, and fertilized by one or more males. Eggs are shaped by the female into discrete clutches deposited in nests at depths of 10-20 cm on intertidal estuarine beaches. Distinguishing between fxesh eggs and the early developmental stages is obfuscated by the large amount of dense, opaque yolk. The first unambiguous confirmation of development is the formation of the rudimentary prosomatie appendages at the ＂limb bud＂ stage. Several days thereafter, the outer chorion is shed and the developing embryo expands and undergoes a series of molts within the clear inner egg membrane. The trilobite （first iustar） stage thus attained may remain within the beach sedi- ments for several more weeks, until hatching is facilitated by environmental factors such as hydration, agitation, and osmotic shock that accompany the infiltration of seawater into the nests. Trilobites exhibit endogenous eirgatidal swimming rhythms that are entrained by mechanical agitation, suggesting that peaks in larval swimming are timed to coincide with periods of high water and the inundation of the nests. larval swimming is limited and does not appear to result in long-distance dispersal. The limited dispersal of the larvae has important implications for the population dynamics of relatively isolated populations. The rate of larval development is highly plastic and is influenced by temperature, salinity, dissolved oxygen, and the presence of pollutants. The broad environmental tolerances of horseshoe crab embryos and larvae are important in understanding their current geographic distribution and their evolutionary persistence

关键词： Horseshoe crab limulus Development Embryo larval dispersal

GREEN INFRASTRUCTURE PlANNING ON CAMPUS CASE STUDIES FROM UNIVERSITY OF MASSACHUSETTS-AMHERST

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Journal of Green Building 2018年第3期13卷 147-157页

作者： robert l.Ryan Department of landscape Architecture and Regional Planning University of MassachusettsAmherstMA 01003

College campuses pride themselves in being leaders in promoting innovation in both technical and theoretical aspects of all fields of study, including sustainability. The drive for sustainability in higher education has become institutionalized in many college campuses in the form of offices of sustainability, as well as membership in the American Association for Sustainability in Higher Education (AASHE). In parallel, but not always in concert, are more grass-roots efforts by students to promote sustainability through recycling programs, urban agriculture, and similar initiatives. Students are often frustrated between the classroom lessons they learn about sustainability and the slow adoption of sustainable practices in the “real-world,” including on campus. In order to address this issue, faculty have begun to engage students in the sustainability challenges facing their own campuses. The Journal of Green Building showcases these projects in the New Directions in Teaching and Research section of the journal. As part of this series, this article will highlight a course at the University of Massachusetts-Amherst in which students engage in green infrastructure planning projects for the campus.

关键词： green infrastructure sustainable campus planning curriculum design student projects

Positive- and Zero-Sequence Impedance Estimation of YNyn0+d-Connected Main Power Transformers in Wind Power Applications

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CSEE Journal of Power and Energy Systems 2021年第1期7卷 57-65页

作者： Franklin l.Quilumba robert E.Jimerson Ken Swift Rafael Garc´ıa with Oncor Electric Delivery Fort WorthTX 76102 USA

With the increased penetration of non-conventionalrenewable energy resources, such as wind power plants (WPPs),into the power system, a lot of interest has been placed on studyingtheir impact for system protection, planning and operationsto ensure continued reliability of the electric grid. The impactof WPPs on the grid is typically identified during generationinterconnection studies. One of the challenges faced by protectionand planning engineers, at an early stage in this process, isthat many of the studies involving these power plants must beperformed without specific data available because the equipmentis not built yet. Among all the needed data, a particular interest inthis study is placed on the positive- and zero-sequence impedancesof the main power transformer (MPT) that interconnects a windpower plant to the transmission system due to its contribution toshort-circuit current during ground faults. The most commonlyfound in practice MPT winding configurations is a high-voltagewinding in wye with neutral bushing;a low-voltage windingin wye with neutral bushing without phase shift between thesewindings, and a stabilizing tertiary winding connected in deltathat is not designed for external loading designated as YNyn0+***, this paper proposes a methodology to estimate the sequenceimpedances of YNyn0+d transformers from a statistical point ofview applying clustering and regression analyses on existing MPTtest report data.

关键词： Positive-and zero-sequence impedance estimation power transformers short-circuit analysis threewinding transformer with buried tertiary wind power integration