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Gap formation around Ω_e/2 and generation of low-band whistler waves by Landau-resonant electrons in the magnetosphere: Predictions from dispersion theory

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earth and Planetary Physics 2020年第2期4卷 138-150页

作者： Konrad Sauer Klaus Baumgartel richard Sydora Max-Planck-Institute for Solar System Research GöttingenGermany(up to 2005 Leibnitz-Institut für Astrophysik(AIP) PotsdamGermany(up to 2008 Institute for Geophysical Research University of AlbertaEdmontonCanada

In this paper we show that two significant phenomena of magnetospheric chorus emission can be explained by the participation of beam-like electron structures,created by Landau-resonant interaction with growing oblique whistler *** first concerns the widely observed spectral gap near half the electron cyclotron frequency Ωe;the second is related to the observation of very obliquely propagating lower-band waves that cannot be directly generated by temperature *** the gap,kinetic dispersion theory reveals that interference of the beam-related cyclotron mode ω~Ωe-kVb with the conventional whistler mode leads to mode splitting and the appearance of a ’forbidden’ area in the ω-k *** the beam velocity appears as an essential *** is directly related to the phase velocity of the most unstable whistler wave mode,which is close to VAe/2 for sufficiently hot electrons(VAe is the electron Alfven velocity).To clarify the second point,we show that Landau-resonant beams with Vb Vbe/2,which arise in cold plasmas from unstable upper-band waves,are able to generate lower-band whistler mode waves at very oblique propagation(θ≥60°).Our studies demonstrate the important role of Landau-resonant electrons in nonlinear whistler wave generation in the magnetosphere.

关键词： important role play Landau-resonant electrons modification of the electron distribution function gap formation at half the electron cyclotron frequency

Direct measurement of the break-out ^(19)F(p,γ)^(20)Ne reaction in the China Jinping underground laboratory(CJPL)

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Nuclear Science and Techniques 2024年第8期35卷 142-152页

作者： Yin‑Ji Chen Hao Zhang Li‑Yong Zhang Jian‑Jun He richard James deBoer Michael Wiescher Alexander Heger David Kahl Jun Su Daniel Odell Xin‑Yue Li Jian‑Guo Wang Long Zhang Fu‑Qiang Cao Zhi‑Cheng Zhang Xin‑Zhi Jiang Luo‑Huan Wang Zi‑Ming Li Lu‑Yang Song Liang‑Ting Sun Qi Wu Jia‑Qing Li Bao‑Qun Cui Li‑Hua Chen Rui‑Gang Ma er‑Tao Li Gang Lian Yao‑De Sheng Zhi‑Hong Li Bing Guo Wei‑Ping Liu Key Laboratory of Beam Technology of the Ministry of education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Department of Physics and Astronomy The Joint Institute for Nuclear AstrophysicsUniversity of Notre DameNotre DameIN 46556USA School of Physics and Astronomy Monash UniversityClaytonVIC 3800Australia Facility for Rare Isotope Beams Michigan State UniversityEast LansingMI 48824USA Institute of Nuclear and Particle Physics and Department of Physics and Astronomy Ohio UniversityAthensOH 45701USA Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China China Institute of Atomic energy Beijing 102413China College of Physics and Optoelectronic engineering Shenzhen UniversityShenzhen 518060China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China College of Science Southern University of Science and TechnologyShenzhen 518055China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China Key Laboratory of Nuclear Physics and Ion‑Beam Application(MOe) Institute of Modern PhysicsFudan UniversityShanghai 200433China School of Mathematics and Physics Handan UniversityHandan 056005China

Calcium production and the stellar evolution of first-generation stars remain fascinating mysteries in *** one possible nucleosynthesis scenario,break-out from the hot carbon–nitrogen–oxygen(HCNO)cycle was thought to be the source of the calcium observed in these oldest ***,according to the stellar modeling,a nearly tenfold increase in the thermonuclear rate ratio of the break-out ^(19)F(p,γ)^(20) Ne reaction with respect to the competing ^(19)F(p,α)^(16) O back-processing reaction is required to reproduce the observed calcium *** performed a direct measurement of this break-out reaction at the China Jinping underground *** measurement was performed down to the low-energy limit of e_(c.m.)=186 keV in the center-of-mass *** key resonance was observed at 225.2 keV for the first *** a temperature of approximately 0.1 GK,this new resonance enhanced the thermonuclear ^(19)F(p,γ)^(20) Ne rate by up to a factor of≈7.4,compared with the previously recommended NACRe *** is of particular interest to the study of the evolution of the first stars and implies a stronger breakdown in their“warm”CNO cycle through the ^(19)F(p,γ)^(20) Ne reaction than previously *** break-out resulted in the production of the calcium observed in the oldest stars,enhancing our understanding of the evolution of the first stars.

关键词： Nuclear astrophysics First stars Abundance of calcium Reaction cross section Reaction rate China Jinping underground laboratory(CJPL) JUNA

Segmental arterial mediolysis: A clinical-pathologic review, its role in fibromuscular dysplasia and description and differential diagnosis of the masquerader-muscular artery cystic necrosis

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World Journal of Cardiovascular Diseases 2013年第1期3卷 64-81页

作者： richard e. Slavin Cascade Pathology Group Department of Pathology Emanuel Hospital and Health Center Portland USA

Segmental arterial mediolysis (SAM) is an uncommon non-inflammatory iatrogenic arteriopathy caused by alpha-1 adrenergic agonists or Beta-2 agonists able to release norepinephrine from the peripheral nervous system. Causative agents include adrenergic agonists used to control blood pressure, B-2 tocolytic agonists, and ractopamine used as a repartitioning agent in animal husbandry. The liberated norepinephrine both injures and stimulates a robust reparative response in the muscular arteries in the abdomen, brain base, and coronary arteries. This response may be augmented by endothelin-1 formed in the arterial adventitia. Three types of arterial lesions develop in the injurious stage: 1) apoptotic induced mediolysis, 2) separation of the outer media from the adventitia and 3) the formation of arterial gaps. The latter enlarge, particularly in elderly patients, to form gap-aneurysms complicated by dissections and dissecting an- eurysms that when ruptured cause the calamitous hemorrhages that clinically announce SAM. The other types of injury remain clinically silent but with repair develop sequelae and can metamorphose into fibromuscular dysplasia. The sequelae are mainly asymptomatic but may cause arterial stenosis and ischemic lesions. The definitive diagnosis of SAM re- quires histological conformation but misinterpreta- tion of smooth muscle vacuolar change has caused di- agnostic errors. Muscular artery cystic necrosis a newly named non-inflammatory muscular artery ar- teriopathy may be confused with SAM both clinically and pathologically. This arteriopathy represents the muscular artery equivalent of cystic media necrosis of the elastic arteries since it exhibits similar morphol- ogic features and can occur concomitantly with this entity. Adrenergic agents to counter hemorrhagic shock in SAM are contraindicated since they may intensify injury and create new lesions. The use of norepinehrine antagonists introduces a new, but as yet untested, treatment option for

关键词： Segmental Arterial Mediolysis Norepinephrine Adrenergic Agonists Ractopamine Arterial Apoptosis Aneurysms Dissecting Hematomas Arterial Fibromuscular Dysplasia Muscular Artery Cystic Necrosis

Combining Micro Technologies and Unmanned Systems to Support Public Safety and Homeland Security

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Journal of Civil engineering and Architecture 2012年第10期6卷 1399-1404页

作者： richard e. Baker Center for Unmanned Systems and Human Capital Development Indiana State University Indiana 4 7809 USA

Previously, the military establishment has been the primary developer and user of micro technologies associated with unmanned systems. As these technologies become available commercially, a need exists to integrate the use of the technology into local or regional public safety and homeland security incidents. The purpose of this presentation is to explain several key factors to consider when using micro technologies and unmanned systems in support of public safety and homeland security officials. Real time information is critical to the decision making process for public safety and homeland security officials to make assessments and quickly resolve crisis situations. Unmanned micro-vehicles and micro technologies are well suited to remotely observe, gather essential information, and immediately relay it to incident responders. These technologies can provide extremely important support during responses to hostage situations, hazardous environments, search and rescue, natural disasters, border patrol and many others. The true benefit is having remote resources providing real time support to incident responders. This paper discusses the use of several different types of micro-vehicle platforms in public safety scenarios and their use of associated technologies such as GPS （Global Positioning System） autopilot, communication, and sensor devices.

关键词： Public safety first responders unmanned systems improved incident response

Routine use of thiopurines in maintaining remission in pediatric Crohn's disease

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World Journal of Gastroenterology 2014年第27期20卷 9185-9190页

作者： Brendan M Boyle Michael D Kappelman richard B Colletti Robert N Baldassano David e Milov Wallace V Crandall Nationwide Children’s Hospital Department of Pediatrics University of North Carolina at Chapel Hill University of Vermont Children’s Hospital of Philadelphia Nemours Children’s Clinic

AIM: To evaluate the effectiveness of thiopurines in maintaining steroid-free remission in routine clinical practice.

关键词： Crohn's disease Pediatric Remission Thiopurines Mercaptopurine

Does disruptive camouflage conceal edges and features？

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Current Zoology 2015年第4期61卷 708-717页

作者： richard J. WeBSTeR Department of Biology Carleton University Ottawa K1S 5B6 Canada

Camouflage is ubiquitous in the natural world and benefits both predators and prey. Amongst the range of conceal- ment strategies, disruptive coloration is thought to visually fragment an animal＇s＇ outline, thereby reducing its rate of discovery. Here, I propose two non-mutually exclusive hypotheses for how disruptive camouflage functions, and describe the visual me- chanisms that might underlie them. （1） The local edge disruption hypothesis states that camouflage is achieved by breaking up edge information. （2） The global feature disruption hypothesis states camouflage is achieved by breaking up the characteristic features of an animal （e.g., overall shape or facial features）. Research clearly shows that putatively disruptive edge markings do increase concealment; however, few tests have been undertaken to determine whether this survival advantage is attributable to the distortion of features, so the global feature disruption hypothesis is under studied. In this review the evidence for global feature disruption is evaluated. Further, I address if object recognition processing provides a feasible mechanism for animals＇ features to influence concealment. This review concludes that additional studies are needed to test if disruptive camouflage operates through the global feature disruption and proposes future research directions [Current Zoology 61 （4）： 708-717, 2015].

关键词： Antipredator Background matching Contour Crypsis Camouflage Disruptive coloration edge detection Objectrecognition

Inactivation of Cdc42 in embryonic brain results in hydrocephalus with ependymal cell defects in mice

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Protein & Cell 2013年第3期4卷 231-242页

作者： Xu Peng Qiong Lin Yang Liu Yixin Jin Joseph e.Druso Marc A.Antonyak Jun-Lin Guan richard A.Cerione Department of Systems Biology and Translational Medicine College of MedicineTexas A&M Health Science CenterTempleTX 76504USA Department of Molecular Medicine Cornell UniversityIthacaNY 14853USA Department of Internal Medicine-Division of Molecular Medicine and Genetics and Department of Cell and Developmental Biology University of Michigan Medical SchoolAnn ArborMI 48109USA

The establishment of a polarized cellular morphology is essential for a variety of processes including neural tube morphogenesis and the development of the ***42 is a Ras-related GTPase that plays an essential role in controlling cell polarity through the regulation of the actin and microtubule cytoskeleton *** studies have shown that Cdc42 plays an indispensable role in telencephalon development in earlier embryo developmental stage(before e12.5).However,the functions of Cdc42 in other parts of brain in later embryo developmental stage or in adult brain remain ***,in order to address the role of Cdc42 in the whole brain in later embryo developmental stage or in adulthood,we used Cre/loxP technology to generate two lines of tissue-specific Cdc42-knock-out *** of Cdc42 was achieved in neuroepithelial cells by crossing Cdc42/flox mice with Nestin-Cre mice and resulted in hydrocephalus,causing death to occur within the postnatal *** analyses of the brains from these mice showed that ependymal cell differentiation was disrupted,resulting in aqueductal *** of Cdc42 in the cerebral cortex also induced obvious defects in interki-netic nuclear migration and *** further explore the role of Cdc42 in adult mice brain,we examined the effects of knocking-out Cdc42 in radial glial cells by crossing Cdc42/flox mice with human glial fi brillary acidic protein(GFAP)-Cre *** of Cdc42 in radial glial cells resulted in hydrocephalus and ependymal cell *** together,these results highlight the importance of Cdc42 for ependymal cell differentiation and maintaining,and suggest that these functions likely contribute to the essential roles played by Cdc42 in the development of the brain.

关键词： Cdc42 small GTPase neuron glial cell polarity development

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effect of drug therapies on self-reported chemosensory outcomes after COVID-19

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 88-96页

作者： Marco A.Fornazieri Bruno M.Cunha Samuel P.Nicácio Lucas K.Anzolin JoséL.B.da Silva Aristides Fernandes Neto Deusdedit Brandão Neto richard L.Voegels Fábio D.R.Pinna Department of Surgery Londrina State UniversityLondrinaBrazil Department of Medicine Pontifical Catholic University of ParanáLondrinaBrazil Department of Otorhinolaryngology University of São PauloSao PauloBrazil Department of Otorhinolaryngology:Head and Neck Surgery Perelman School of MedicineSmell and Taste CenterUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA

Objective:The aim of this study was to assess the relative efficacy of medications used following severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection on self-reported alterations in taste and/or smell ***:Seven hundred and fourteen persons with self-reported postcoronavirus disease 2019(post-COVID-19)chemosensory disorders were personally interviewed regarding specific medications they were administered following the acute phase of the *** dependent measure—self-reported total recovery of chemosensory symptoms—was subjected to stepwise logistic *** predictors included demographic and clinical variables,in addition to specific medications used to mitigate disease symptoms(i.e.,systemic corticosteroids,oseltamivir,vitamin C,ibuprofen,hydroxychloroquine,azithromycin,ivermectin,nitazoxanide,anticoagulants,and zinc).Results:The median time between COVID-19 symptom onset and the interviews was 81 days(interquartile range:60-104).Of the 714 subjects,249(34.9%)reported total recovery of their chemosensory function;437(61.2%)had at least one treatment since the beginning of the *** and those with more comorbidities had undergone more *** recovery rates of the treated and nontreated groups did not differ ***,respondents who had used nitazoxanide tended to have a higher rate of self-reported taste or smell *** who took oral zinc were less likely to ***:No medication employed during the first months after SARS-CoV-2 infection had a clear positive effect on returning self-reported smell or taste function to normal,although nitrazoxide trended in a positive *** zinc had a negative effect on the reported recovery of these senses.

关键词： chemosensory disorder coronavirus infections COVID-19 drug therapy SARS-CoV-2 smell loss taste loss

Nelson Textbook of Pediatrics

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