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Bandwidth limits of luminescent solar concentrators as detectors in free-space optical communication systems

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Light(science & Applications) 2021年第1期10卷 29-40页

作者： Mark Portnoi Paul Anthony Haigh Thomas JM acdonald Filip Ambroz ivan PParkin Izzat Darwazeh loannis Papakonstantinou Photonic Innovations Lab Department of Electronic and Electrical EngineeringUniversity College LondonLondon WC1E 7JEUK school of Engineering University of NewcastleNewcastle NE17RUUK Department of Chemistry Imperial College LondonLondon W12 OBZUK Department of Chemistry University College LondonLondon WC1H OAJUK Department of Electronic and Electrical Engineering University College LondonLondon WC1E 7JEUK

Luminescent solar concentrators(LsCs)have recently emerged as a promising receiver technology in free-space optical communications due to their inherent ability to collect light from a wide field-of-view and concentrate it into small areas,thus leading to high optical *** high-speed communication systems integrating LsCs in their detector blocks have already been demonstrated,with the majority of efforts so far being devoted to maximising the received optical power and the system's ***,LsCs may pose a severe bottleneck on the bandwidth of such communication channels due to the comparably slow timescale of the fluorescence events involved,a situation further aggravated by the inherent reabsorption in these systems,and yet,an in-depth study into such dynamic effects remains absent in the *** fill this gap,we have developed a comprehensive analytical solution that delineates the fundamental bandwidth limits of LsCs as optical detectors in arbitrary free-space optical links,and establishes their equivalence with simple RC low-pass electrical ***,we demonstrate a time-domain Monte Carlo simulation platform,an indispensable tool in the multiparameter optimisation of LsC-based receiver *** work offers vital insight into LsC system dynamic behaviour and paves the way to evaluate the technology for a wide range of applications,including visible light communications,high-speed video recording,and real-time biological imaging,to name a few.

关键词： communication integrating devoted

How to treat intestinal obstruction due to malignant recurrence after Whipple's resection for pancreatic head cancer: description of 2 new endoscopic techniques

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World Journal of Gastroenterology 2017年第33期23卷 6181-6186页

作者： Christina Mouradides Alaa Taha ivan Borbath Pierre H Deprez Tom G Moreels Cliniques universitaires saint-Luc

The prognosis of pancreatic cancer remains poor,even after initial surgical therapy. Local recurrence after Whipple's pancreatico-duodenectomy may lead to intestinal obstruction at the level of the afferent limb or the alimentary limb. Endoscopic insertion of a selfexpandable metal stent(sEMs) into the intestinal malignant stricture is the preferred method of choice for palliation. We describe two new endoscopic techniques to treat a malignant intestinal obstruction with the insertion of a sEMs into the afferent limb and the alimentary limb. A case of malignant gastric outlet obstruction after a Whipple's resection was treated by the creation of an endoscopic gastrojejunostomy by the insertion of a lumen apposing Hot Axios stent in between the stomach and the alimentary limb under fluoroscopic and endoscopic ultrasound control. Biliary obstruction and jaundice caused by a malignant stricture of the afferent limb after a Roux-en-Y Whipple's resection was treated by the insertion of a sEMs by means of the single-balloon overtube-assisted technique under fluoroscopic control. Feasibility and advantages of both techniques are discussed.

关键词： Intestinal obstruction self-expandable metal stent Whipple’s pancreatico-duodenectomy

Growth of skyrmionic Mnsi nanowires on si： Critical importance of the siO2 layer

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Nano Research 2014年第12期7卷 1788-1796页

作者： siwei Tang ivan Kravchenko Jieyu Yi Guixin cao Jane Howe David Mandrus Zheng Gai Department of Materials science and Engineering University of Tennessee Knoxville TN 37996 USA Center for Nanophase Materials sciences Oak Ridge National Laboratory Oak Ridge TN 37831 USA Hitachi High Technologies Inc. Rexdale ON M9W 6A4 Canada

Mnsi in the B20 structure is a prototypical helimagnet that forms a skyrmion lattice, a vortex-like spin texture under applied magnetic field. We have systematically explored the synthesis of single crystal Mnsi nanowires via controlled oxide-assisted chemical vapor deposition and observed a characteristic signature of skyrmion magnetic ordering in the Mnsi nanowires. The thickness of the siO2 layer on the si substrate plays the key role in obtaining a high yield of B20 Mnsi skyrmion nanowires. A growth mechanism was proposed that is consistent with the existence of an optimum siO2 thickness. A growth phase diagram was constructed based on the extensive studies of various growth conditions for various Mnsi nanostructures. The persistence of both the helicoidal and skyrmion magnetic ordering in the one-dimensional wires was directly revealed by ac and dc magnetic measurements.

关键词： skyrmion spintronics oxide-assisted growth nanowires magnetic materials

Peripheral and mesenteric serum levels of CEA and cytokeratins,staging and histopathological variables in colorectal adenocarcinoma

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World Journal of Gastroenterology 2008年第43期14卷 6699-6703页

作者： ivan Gregório ivankovics Luis César Fernandes sarhan sydeney saad Delcio Matos Coloproctology Group Discipline of Surgical GastroenterologyDepartment of SurgeryFederal University of So Paulo-Escola Paulista de MedicinaSo Paulo-SP04005-004Brazil

AIM： To evaluate the differences that exist bet- ween peripheral and mesenteric serum levels of carcinoembryonic antigen （CEA） and cytokeratins in patients with colorectal adenocarcinoma. METHODs： One hundred and thirty-eight patients with colorectal adenocarcinoma who underwent surgery at Hospital sao Paulo （Discipline of surgical Gastroenterology of UNIFEsP-EPM） between December 1993 and March 2000 were retrospectively analyzed. Differences between CEA and cytokeratin （TPA-M） levels in peripheral blood （P） and in mesenteric blood （M） were studied. Associations were investigated between peripheral and mesenteric levels and the staging and histopathological variables （degree of cell differentiation, macroscopic appearance, tumor dimensions and presence of lymphatic and venous invasion）. REsULTs： Differences were observed in the numerical values of the marker levels： CEA （M）（39.10 mg/1 ± 121.19 mg/L） vs CEA （P）（38.5 mg/L ± 122.55 mg/L）, P 〈 0.05; TPA-M （M）（325.06 U/L ±527.29 U/L） vs TPA-M （P）（279.48 U/L ±455.81 U/L）, P 〈 0.01. The mesenteric CEA levels were higher in more advanced tumors （P 〈 0.01）, in vegetating lesions （34.44 mg/L ± 93.07 mg/L）（P 〈 0.01） and with venous invasion （48.41 mg/L ± 129.86 mg/L）（P 〈 0.05）. Peripheral CEA was higher with more advanced staging （P 〈 0.01）and in lesions with venous invasion （53.23 mg/L ± 258.57 mg/L）（P 〈 0.05）. The patients demonstrated increased mesenteric and peripheral TPA-M levels with more advanced tumors （P 〈 0.01 and P 〈 0.01） and in non-ulcerated lesions [530.45 U/L =1= 997.46 U/L （P 〈 0.05） and 457.95 U/L ± 811.36 U/L （P 〈 0.01）]. CONCLUsION： The mesenteric levels of the tumor markers CEA and cytokeratins were higher than the peripheral levels in these colorectal adenocarcinoma patients, Higher levels of these biologic tumor markers are associated with an advanced state of cancerous dissemination

关键词： Colonic neoplasms Rectal neoplasms Biological tumor markers Carcinoembryonic antigen Cytokeratins

Incidental adenocarcinoma in patients undergoing surgery for stricturing Crohn's disease

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World Journal of Gastroenterology 2017年第3期23卷 472-477页

作者： ivan Kristo stefan Riss stanislaus Argeny svenja Maschke Praminthra Chitsabesan Anton stift Department of surgery Medical University of Vienna1090 WienAustria Department of surgery York Teaching HospitalYork YO31 8HEUnited Kingdom

AIM To evaluate frequency and clinical course of incidental adenocarcinoma in patients with stricturing Crohn's disease(CD).METHODs In this study, consecutive patients, who were operated on for stricturing CD between 1997-2012, were included at an academic tertiary referral center. Demographic data and clinical course were obtained by an institutional database and individual chart review. Besides baseline characteristics, intraoperative findings and CD related history were also recorded. Colorectal cancer was classified and staged according to the Union for International Cancer Control(UICC).REsULTs During the study period 484 patients underwent resections due to stricturing CD. Incidental adenocarcinoma was histologically confirmed in 6(1.2%) patients(4 males, 2 females). Patients diagnosed with colorectal cancer had a median age of 43(27-66)years and a median history of CD of 16(7-36) years. Malignant lesions were found in the rectum(n = 4, 66.7%), descending colon(n = 1, 16.7%) and ileocolon(n = 1, 16.7%). According to the UICC classification two patients were stages as?Ⅰ(33.3%), whereas the other patients were classified as stage ⅡA(16.7%), stage ⅢB(16.7%), stage ⅢC(16.7%) and stage Ⅳ(16.7%), respectively. After a median follow-up of 2(0.03-8) years only 1 patient is still *** The frequency of incidental colorectal cancer in patients, who undergo surgery for stenotic CD, is low but associated with poor prognosis. However, surgeons need to be aware about the possibility of malignancy in stricturing CD, especially if localized in the rectum.

关键词： stenosis Incidental Colorectal Crohn's disease Cancer Gastrointestinal

The use of metal hydrides in fuel cell applications

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Progress in Natural science:Materials International 2017年第1期27卷 3-20页

作者： Mykhaylo V.Lototskyy ivan Tolj Lydia Pickering Cordellia sita Frano Barbir Volodymyr Yartys HysA systems Competence Centre South African Institute for Advanced Materials Chemistry (SAIAMC) University of the Western Cape University of split Faculty of Electrical Engineering Mechanical Engineering and Naval Architecture Department of Thermodynamics and Heat Engines Institute for Energy Technology Kjeller

This paper reviews state-of-the-art developments in hydrogen energy systems which integrate fuel cells with metal hydride-based hydrogen storage. The 187 reference papers included in this review provide an overview of all major publications in the field, as well as recent work by several of the authors of the review. The review contains four parts. The first part gives an overview of the existing types of fuel cells and outlines the potential of using metal hydride stores as a source of hydrogen fuel. The second part of the review considers the suitability and optimisation of different metal hydrides based on their energy efficient thermal integration with fuel *** performances of metal hydrides are considered from the viewpoint of the reversible heat driven interaction of the metal hydrides with gaseous H;. Efficiencies of hydrogen and heat exchange in hydrogen stores to control H;charge/discharge flow rates are the focus of the third section of the review and are considered together with metal hydride – fuel cell system integration issues and the corresponding engineering solutions. Finally, the last section of the review describes specific hydrogen-fuelled systems presented in the available reference data.

关键词： Fuel cells Hydrogen storage Metal hydrides Thermal integration system development

Hypertensive emergency versus preeclampsia in a patient with sickle cell disease:a case report

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World Journal of Emergency Medicine 2023年第4期14卷 329-331页

作者： Jigar Patel Juan A Reyes ivan Berezowski Quincy K Tran sarah E Frasure Ali Pourmand Division of Hospital Medicine Department of Medicinethe George Washington UniversityWashington DC 20037USA Department of Emergency Medicine University of Maryland School of MedicineBaltimore 21201-1544USA Program in Trauma the R Adams Cowley Shock Trauma CenterUniversity of Maryland School of MedicineBaltimore 21201USA Department of Emergency Medicine the George Washington University School of Medicine and Health SciencesWashington DC 20037USA

sickle cell disease(sCD)is strongly associated with severe preeclampsia and has also been linked to poor pregnancy-related ***,sickle cell nephropathy(sCN)is a common complication of sCD and results in chronic *** patients with sCD who present to the emergency department(ED)with pulmonary edema,hypertension,and proteinuria may suffer from a hypertensive emergency with or without *** prior lab work to determine whether a patient’s proteinuria or kidney dysfunction is new or at baseline,it may be impossible for the emergency physician to determine which diagnosis is more ***,amultidisciplinary approach which involves cardiology,nephrology,medicine and obstetrics consultations should be utilized to help direct *** present the case of a 39-yearold patient with sCD,who was also 26 weeks pregnant,and presented to the ED with markedly elevated blood pressure and *** she was initially admitted to the obstetrics ward for blood pressure management given concern for preeclampsia,she was ultimately diagnosed with hypertensive emergency and sickle cell nephropathy.

关键词： hypertensive admitted markedly

Transcatheter Ventricular septal Defect Closure with Nit-Occlud LêVsD Device—Five Years’Experience and Literature Review

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Congenital Heart Disease 2023年第3期18卷 361-371页

作者： ivana B.Cerović Vladislav A.Vukomanović Jovan Lj.Košutić Mila s.stajević sanja s.Ninić saša s.Popović ivan D.Dizdarević staša D.Krasić sergej M.Prijić Cardiology Department Mother and Child Health Institute of Serbia“Dr VukanČupić”Belgrade11070Serbia Faculty of Medicine University of BelgradeBelgrade11070Serbia

Introduction:Transcatheter closure is an alternative to ventricular septal defect(VsD)occlusion ***-Occlud LêVsD coil is a new device yet to be *** study aimed to evaluate immediate and midterm results after transcatheter closure with the Nit-Occlud LêVsD ***:The retrospective analysis included 30 patients with VsD referred for closure during the period from October 2015 to December ***:At the time of intervention,the patients’mean age and body weights were 7.5±5.6 years and 29.3±19.1 *** majority of the defects had perimembranous location(24/30),four defects had muscular and two outlet subaortic *** mean effective right-side diameter of the VsDs was 3.6±1.3 *** ventricular fibrillation,device embolization,and hemolysis developed in different patients and were successfully *** of the patients had a complete atrioventricular *** coil was successfully placed in 25/30(83.3%)*** majority of the devices were 10 mm×6 mm(11/25)and 12 mm×8 mm(8/25)in *** patients required the implantation of a second *** follow-up period was 2.1±1.4 *** VsD closure was achieved in 48%of cases immediately after the intervention,74%during 2.1±1.6 months after the procedure,and 81%over *** remaining patients had a trivial residual *** the follow-up,approximately one-third of patients developed trivial aortic and mitral valve regurgitation,and half of the patients acquired trace/mild tricuspid ***(z-score)left ventricular end-diastolic diameter(0.15±0.37 vs.0.92±0.82,p=0.005)and left atrium dimension(0.47±0.58 vs.1.89±1.11,p=0.005),as well as the left atrium to aortic root ratio(1.2±0.1 vs.1.4±0.2,p=0.005)showed a significant decrease over follow-up related to the period before ***:Intervention with Nit-OccludLêVsD coil showed appropriate results regarding VsD closure rate,complications,and chamber *** introduction of t

关键词： Ventricular septal defect transcatheter device children

Competing magnetic states in silicene and germanene 2D ferromagnets

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Nano Research 2020年第12期13卷 3396-3402页

作者： Dmitry V.Averyanov ivan s.sokolov Mikhail s.Platunov Fabrice Wilhelm Andrei Rogalev Pierluigi Gargiani Manuel Valvidares Nicolas Jaouen Oleg E.Parfenov Alexander N.Taldenkov Igor A.Karateev Andrey M.Tokmachev Vyacheslav G.storchak National Research Center“Kurchatov Institute” Kurchatov Sq.1Moscow123182Russia EsRF-The European synchrotron CS 4022038043Grenoble Cedex 9France ALBA synchrotron Light source Cerdanyola del Vallès08290BarcelonaSpain L’Orme des Merisiers Synchrotron SOLEILGyf-sur-Yvette91192France

Two-dimension(2D)magnets have recently developed into a class of stoichiometric materials with prospective applications in ultra-compact spintronics and quantum *** functionality is particularly rich when different magnetic orders are competing in the same *** REX2(RE=Eu,Gd;X=si,Ge),silicene or germanene—heavy counterparts of graphene—coupled with a layer of rare-earth metals,evolve from three-dimension(3D)antiferromagnets in multilayer structures to 2D ferromagnets in a few *** evolution,however,does not lead to fully saturated 2D ferromagnetism,pointing at a possibility of coexisting/competing magnetic ***,REX2 magnetism is explored with element-selective X-ray magnetic circular dichroism(XMCD).The measurements are carried out for Gdsi2,Eusi2,GdGe2,and EuGe2 of different thicknesses down to 1 monolayer employing K absorption edges of si and Ge as well as M and L edges of the *** access the magnetic state in REX2 and determine the seat of magnetism,orbital,and spin contributions to the magnetic ***-field measurements probe remnants of the bulk antiferromagnetism in 2D *** results provide a new platform for studies of complex magnetic structures in 2D materials.

关键词： silicene germanene 2D ferromagnetism X-ray magnetic circular dichroism(XMCD) monolayer