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Free-electron crystals for enhanced X-ray radiation

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Light(Science & Applications) 2024年第7期13卷 1299-1309页

作者： Lee Wei wesley Wong Xihang Shi Aviv Karnieli Jeremy Lim Suraj Kumar Sergio Carbajo Ido Kaminer Liang Jie Wong School of Electrical and Electronic Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore. Solid State Institute and Faculty of Electrical and Computer Engineering Technion–Israel Institute of TechnologyHaifa 3200003Israel. School of Electrical Engineering Fleischman Faculty of EngineeringTel Aviv UniversityTel Aviv 69978Israel Department of Applied Physics Stanford UniversityStanfordCA 94305USA. Science Mathematics and TechnologySingapore University of Technology and Design8 Somapah RoadSingapore 487372Singapore. Electrical and Computer Engineering Department UCLA420 WestwoodLos AngelesCA 90095USA. Physics and Astronomy Department UCLA475 Portola PlazaLos AngelesCA 90095USA. SLAC National Accelerator Laboratory Stanford University2575 Sand Hill RoadMenlo ParkCA 94025USA

Bremsstrahlung—the spontaneous emission of broadband radiation from free electrons that are deflected by atomic nuclei—contributes to the majority of X-rays emitted from X-ray tubes and used in applications ranging from medical imaging to semiconductor chip ***,we show that the bremsstrahlung intensity can be enhanced significantly—by more than three orders of magnitude—through shaping the electron wavefunction to periodically overlap with atoms in crystalline ***,we show how to shape the bremsstrahlung X-ray emission pattern into arbitrary angular emission profiles for purposes such as unidirectionality and ***,we find that these enhancements and shaped emission profiles cannot be attributed solely to the spatial overlap between the electron probability distribution and the atomic centers,as predicted by the paraxial and nonrecoil theory for free electron light *** work highlights an unprecedented regime of free electron light emission where electron waveshaping provides multi-dimensional control over practical radiation processes like *** results pave the way towards greater versatility in table-top X-ray sources and improved fundamental understanding of quantum electron-light interactions.

关键词： overlap attributed arbitrary

Localized-states quantum confinement induced by roughness in CdMnTe/CdTe heterostructures grown on Si(111) substrates

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Journal of Semiconductors 2024年第9期45卷 28-35页

作者： Leonarde N.Rodrigues wesley F.Inoch Marcos L.F.Gomes Odilon D.D.Couto Jr. Bráulio S.Archanjo Sukarno O.Ferreira Physics Department Federal University of ViçosaViçosa36570-900Minas GeraisBrazil Instituto de Física Gleb Wataghin Universidade Estadual de CampinasCampinas13083-859São PauloBrazil National Institute of Metrology Quality and Technology(Inmetro) Materials Metrology Division(DIMAT)Xerém2525-020Rio de JaneiroBrazil

This work shows that despite a lattice mismatch of almost 20%, CdMnTe/CdTe/CdMnTe heterostructures grown directly on Si(111) have surprisingly good optical emission properties. The investigated structures were grown by molecular beam epitaxy and characterized by scanning transmission electron microscopy, macro-and micro-photoluminescence. Low temperature macro-photoluminescence experiments indicate three emission bands which depend on the CdTe layer thickness and have different confinement characteristics. Temperature measurements reveal that the lower energy emission band (at 1.48 eV)is associated to defects and bound exciton states, while the main emission at 1.61 eV has a weak 2D character and the higher energy one at 1.71 eV has a well-defined (zero-dimensional, 0D) 0D nature. Micro-photoluminescence measurements show the existence of sharp and strongly circularly polarized (up to 40%) emission lines which can be related to the presence of Mn in the heterostructure. This result opens the possibility of producing photon sources with the typical spin control of the diluted magnetic semiconductors using the low-cost silicon technology.

关键词： CdMnTe/CdTe/CdMnTe heterostructure CdTe/CdMnTe quantum emitters quantum dot-like emission silicon(111)substrate

Rescue from complications after pancreaticoduodenectomies at a low-volume Caribbean center:Value of tailored peri-pancreatectomy protocols

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 681-688页

作者： Shamir O Cawich Elijah Dixon Parul J Shukla Shailesh V Shrikhande Rahul R Deshpande Fawwaz Mohammed Neil W Pearce wesley Francis Shaneeta Johnson Johann Bujhawan Department of Surgery University of the West IndiesSt Augustine 000000Trinidad and Tobago Department of Surgery Faculty of MedicineUniversity of CalgaryCalgaryAlberta T2N2T9Canada Department of Surgery Weill Cornell Medical CollegeNew YorkNY 10065United States Department of Surgical Oncology Tata Memorial CenterHomi Bhabha National UniversityMumbai 400012India Department of Surgery Manchester Royal InfirmaryManchester M139WLUnited Kingdom University Surgical Unit Southampton General HospitalSouthampton SO166YDUnited Kingdom Department of Surgery University of the West IndiesNassau N-1184Bahamas Department of Surgery Morehouse School of MedicineAtlantaGA 30310United States Department of Surgery General Hospital in Port of SpainPort of Spain 000000Trinidad and Tobago

BACKGROUND Pancreaticoduodenectomy(PD)is a technically complex operation,with a re-latively high risk for *** ability to rescue patients from post-PD complications is as a recognized quality *** protocols were instituted at our low volume facility in the year *** To document the rate of rescue from post-PD complications with tailored protocols in place as a measure of *** A retrospective audit was performed to collect data from patients who experienced major post-PD complications at a low volume pancreatic surgery unit in Trinidad and Tobago between January 1,2013 and June 30,***-dardized definitions from the International Study Group of Pancreatic Surgery were used to define post-PD complications,and the modified Clavien-Dindo classification was used to classify post-PD *** Over the study period,113 patients at a mean age of 57.5 years(standard deviation[SD]±9.23;range:30-90;median:56)underwent PDs at this *** complications were recorded in 33(29.2%)patients at a mean age of 53.8 years(SD:±7.9).Twenty-nine(87.9%)patients who experienced major morbidity were salvaged after aggre-ssive treatment of their ***(3.5%)died from bleeding pseudoaneurysm(1),septic shock secondary to a bile leak(1),anastomotic leak(1),and myocardial infarction(1).There was a significantly greater salvage rate in patients with American Society of Anesthesiologists scores≤2(93.3%vs 25%;P=0.0024).CONCLUSION This paper adds to the growing body of evidence that volume alone should not be used as a marker of quality for patients requiring *** low volumes at our facility,we demonstrated that 87.9%of patients were rescued from major *** attributed this to several factors including development of rescue protocols,the competence of the pancreatic surgery teams and continuous,and adaptive learning by the entire institution,cul-minating in the development of tailored peri-pancreatectomy protoc

关键词： Pancreas Complication Rescue Failure Morbidity Mortality Pancreaticoduodenectomy

Measuring Resilience in the Assumed City

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International Journal of Disaster Risk Science 2022年第3期13卷 317-329页

作者： wesley Cheek Ksenia Chmutina Department of Geography and Geology Edge Hill UniversityOrmskirkL394QPUK School of Architecture Building and Civil EngineeringLoughborough UniversityLoughboroughLE113TUUK

The malleable nature of both the idea of a city and the idea of resilience raises an important question—why measure?Resilience is assumed to be located in the physical infrastructure of specific places or as a quality of the people located *** disasters,we are often trying to conceptualize,measure,or render legible resilience in physical *** what is it that we are trying to measure,and is the idea of a city reflected in these measurements?If cities are organized around something other than resilience,is resilience their natural by-product?What is necessitating the need for increased—and measured—resilience?Using interpretive policy analysis,we explored five well known disaster resilience frameworks(UNDRR's Making Cities Resilient Campaign,UN-Habitat's City Resilience Profiling Programme,The World Bank and GFDRR's Resilient Cities Program,Arup and The Rockefeller Foundation's City Resilience Index,and The Rockefeller Foundation's 100 Resilient Cities)to identify the working definition of‘‘city''and of‘‘resilience.''We conclude that if the demand for cities to become more resilient is an acknowledgment of the risk produced by globalized urbanization,then the call itself is an indictment of the current state of our cities.

关键词： City planning and design Disaster governance Resilience frameworks Urban theory

Suppression of Self-Discharge in Aqueous Supercapacitor Devices Incorporating Highly Polar Nanofiber Separators

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Energy & Environmental Materials 2023年第3期6卷 74-86页

作者： wesley G.Buxton Simon G.King Vlad Stolojan Advanced Technology Institute University of SurreyGuildford SurreyGU27XHUK

One of the major problems limiting the applications of electric double-layer(EDLC)supercapacitor devices is their inability to maintain their cell voltage over a significant ***-discharge is a spontaneous decay in charged energy,often resulting in fully depleted devices in a matter of ***,a new method for suppressing this self-discharge phenomenon is proposed by using directionally polarized piezoelectric electrospun nanofiber films as separator *** engineering of polyvinylidene fluoride(PVDF)nanofiber films containing a small concentration of sodium dodecyl sulfate(SDS)results in a high proportion of polarβphases,reaching 380.5%of the total *** polarity into the separator material provides a reverse-diode mechanism in the device,such that it drops from an initial voltage of 1.6 down to 1 V after 10 h,as opposed to 0.3 V with a nonpolarized,commercial separator ***,the energy retained for the polarized separator is 37%and 4%for the nonpolarized separator,making supercapacitors a more attractive solution for long-term energy storage.

关键词： piezoelectric polar nanofibers PVDF separators self-discharge supercapacitors

Time's up:mutation rate and lifespan

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Signal Transduction and Targeted Therapy 2022年第9期7卷 3166-3167页

作者： Anjali Cremer wesley T.Abplanalp Michael A.Rieger Department of Medicine Hematology/OncologyGoethe University FrankfurtFrankfurt am MainGermany Frankfurt Cancer Institute Frankfurt am MainGermany German Cancer Consortium(DKTK)and German Cancer Research Center(DKTK) HeidelbergGermany Institute for Cardiovascular Regeneration Centre of Molecular MedicineGoethe University FrankfurtFrankfurt am MainGermany German Center for Cardiovascular Research DZHK Partner site Frankfurt Rhine-MainBerlinGermany Cardiopulmonary Institute Goethe University FrankfurtFrankfurtGermany EnABLE Consortium Goethe University FrankfurtFrankfurtGermany

In a recent study published in Nature,Alex Cagan,Adrian Baez-Ortega and colleagues found that many mammalian species present a similar somatic mutational load at the end of *** mutational burden is independent of lifetime and body mass,only varying by a relatively small fold change among species.1These data may suggest that mutational burden predicts mortality.

关键词： species. life lifetime

Impact of sports participation on cardiovascular health markers of children and adolescents: Systematic review and meta-analysis

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World Journal of Clinical Pediatrics 2022年第4期11卷 375-384页

作者： wesley Torres Santiago Maillane-Vanegas Jacqueline Bexiga Urban Romulo Araujo Fernandes Department of Physical Education Sao Paulo State University-UNESPPresidente Prudente 19060900Sao PauloBrazil

BACKGROUND Cardiovascular diseases have a high prevalence in adults and their development begins in the first decades of *** the other hand,sports participation in childhood and adolescence provides benefits which can delay the onset of these *** To synthesize the available literature on the impact of sports participation on cardiovascular outcomes in children and *** This systematic review was conducted on studies of children and adolescents(aged 8-18 years)who regularly practiced a sport and had reported cardiovascular outcomes(blood pressure and intima-media thickness)*** Medline/PubMed,SciELO,Reference Citation Analysis(https://*** ***/)and Bireme databases were *** In total,3314 publications for blood pressure and 122 publications for intimamedia thickness were identified in the *** exclusions(e.g.,duplicate articles,animal studies and those that did not meet the inclusion criteria),four publications for blood pressure(449 adolescents)and two publications for intimamedia thickness were included(402 adolescents).For blood pressure,all publications were longitudinal in design(follow-up ranging from 12 wk to 12 mo)and involved adolescents aged from 8 years to 18 years of *** intima-media thickness,both publications were longitudinal in design and involved adolescents aged from 11 years to 18 years of *** Sports participation seems to promote benefits to cardiovascular structure and function in ***,studies with adolescents are scarce and further research is needed to understand this phenomenon.

关键词： Pediatrics Adolescents Sports Blood pressure Intima-media thickness

Intestinal inflammation and the microbiota:Beyond diversity

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World Journal of Gastroenterology 2022年第26期28卷 3274-3278页

作者： Gabriela Gama Freire Alberca Naiane Samira Souza Cardoso Rosa Liliana Solis-Castro Viviane Nakano Ricardo wesley Alberca Department of Microbiology Institute of Biomedical SciencesUniversity of São PauloSão Paulo 05508-000Brazil Departamento Académico de Biología Bioquímica Facultad de Ciencias de la SaludUniversidad Nacional de TumbesPampa Grande 24000TumbesPeru Laboratorio de Dermatologia e Imunodeficiencias Departamento de DermatologiaFaculdade de Medicina FMUSPUniversidade de São PauloSão Paulo 01246-903Brazil

The recent manuscript entitled“Relationship between clinical features and intestinal microbiota in Chinese patients with ulcerative colitis”reported a difference in the intestinal microbiota of patients with ulcerative colitis according to the severity of the *** influence of the intestinal microbiota on the development and progress of gastrointestinal disorders is well *** the diversity in the microbiome,the presence of virulence factors and toxins by commensal bacteria may affect an extensive variety of cellular processes,contributing to the induction of a proinflammatory environment.

关键词： Inflammation Microbiota Toxins Intestinal Ulcerative Colitis Cancer

A Longer Siesta?DN1s in Control!

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Neuroscience Bulletin 2017年第1期33卷 113-114页

作者： wesley A.Leigh Yong Zhang Department of Biology University of NevadaReno1664 NVirginia StRenoNV 89557USA

Sleep is an essential behavior that is conserved in most animal species. Two molecular mechanisms regulate sleep： circadian clocks for the timing of sleep, and a homeostatic process for the amount of sleep [1]. The fruit fly, Drosophila melanogaster, exhibits robust sleep behavior and serves as an excellent model in which to study the neuronal and molecular mechanisms of sleep.

关键词： In A Longer Siesta?DN1s in Control DN