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A flexible protruding microelectrode array for neural interfacing in bioelectronic medicine

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Microsystems & Nanoengineering 2022年第6期8卷 165-179页

作者： Helen Steins Michael Mierzejewski Lisa Brauns Angelika Stumpf Alina Kohler Gerhard Heusel Andrea Corna Thoralf Herrmann Peter D.Jones Günther Zeck rene von Metzen Thomas Stieglitz NMI Natural and Medical Sciences Institute at the University of Tübingen ReutlingenGermany Laboratory for Biomedical Microtechnology Department of Microsystems EngineeringUniversity of FreiburgFreiburgGermany Institute of Biomedical Electronics TU WienViennaAustria Bernstein Center Freiburg University of FreiburgFreiburgGermany BrainLinks-BrainTools University of FreiburgFreiburgGermany

Recording neural signals from delicate autonomic nerves is a challenging task that requires the development of a lowinvasive neural interface with highly selective,micrometer-sized *** paper reports on the development of a three-dimensional(3D)protruding thin-film microelectrode array(MEA),which is intended to be used for recording low-amplitude neural signals from pelvic nervous structures by penetrating the nerves transversely to reduce the distance to the *** gold pillars(O 20 or 50μm,~60μm height)were fabricated on a micromachined polyimide substrate in an electroplating *** sidewalls were insulated with parylene C,and their tips were optionally modified by wet etching and/or the application of a titanium nitride(TiN)*** microelectrodes modified by these combined techniques exhibited low impedances(~7 kΩ at 1 kHz for ∅ 50μm microelectrode with the exposed surface area of~5000μm^(2))and low intrinsic noise *** functionalities were evaluated in an ex vivo pilot study with mouse retinae,in which spontaneous neuronal spikes were recorded with amplitudes of up to 66μ*** novel process strategy for fabricating flexible,3D neural interfaces with low-impedance microelectrodes has the potential to selectively record neural signals from not only delicate structures such as retinal cells but also autonomic nerves with improved signal quality to study neural circuits and develop stimulation strategies in bioelectronic medicine,e.g.,for the control of vital digestive functions.

关键词： neural microelectrode electronic

High-voltage direct current fault current interruption:A technology review

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High Voltage 2021年第2期6卷 171-192页

作者： rene P.P.Smeets Nadew A.Belda Innovation KEMA LabsArnhemNetherlands

This review paper describes fault current interruption principles and various high-voltage direct currrent(HVDC)circuit breaker ***,fundamentals of HVDC fault current interruption and a generic set of requirements of HVDC circuit breakers are *** critical parameters during fault current interruption are assessed using a simplified mathematical ***,the state-of-the-art of HVDC circuit breaker technologies and their application in actual HVDC multi-terminal projects is *** sub-components of HVDC circuit breakers are standard components used in a non-standard application and,hence,have to face non-standard *** of today's HVDC circuit breaker technologies consist of mechanical switching devices and metal-oxide surge arresters,which are used in an unconventional way.A critical analysis of these stresses compared to the stresses in a conventional application is ***-mendations on testing supported with examples of actual full-power‘complete’demonstration of HVDC circuit breakers up to 350 kV/20 kA are ***,the actual status of standardisation activities is presented.

关键词： fault critical hence

Low threshold anti-Stokes Raman laser on-chip

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Photonics Research 2019年第8期7卷 926-932页

作者： HYUNGWOO CHOI DONGYU CHEN FAN DU rene ZETO ANDREA ARMANI Mork Family Department of Chemical Engineering and Materials Science University of Southern CaliforniaLos AngelesCalifornia90089USA Ming Hsieh Department of Electrical Engineering-Electrophysics University of Southern CaliforniaLos AngelesCalifornia90089USA

Raman lasers based on integrated silica whispering gallery mode resonant cavities have enabled numerous applications from telecommunications to biodetection. To overcome the intrinsically low Raman gain value of silica, these devices leverage their ultrahigh quality factors(Q), allowing submilliwatt stimulated Raman scattering(SRS) lasing thresholds to be achieved. A closely related nonlinear behavior to SRS is stimulated anti-Stokes Raman scattering(SARS). This nonlinear optical process combines the pump photon with the SRS photon to generate an upconverted photon. Therefore, in order to achieve SARS, the efficiency of the SRS process must be high. As a result, achieving SARS in on-chip resonant cavities has been challenging due to the low lasing efficiencies of these devices. In the present work, metal-doped ultrahigh Q(Q > 10~7) silica microcavity arrays are fabricated on-chip. The metal-dopant plays multiple roles in improving the device performance. It increases the Raman gain of the cavity material, and it decreases the optical mode area, thus increasing the circulating intensity. As a result, these devices have SRS lasing efficiencies that are over 10× larger than conventional silica microcavities while maintaining low lasing thresholds. This combination enables SARS to be generated with submilliwatt input powers and significantly improved anti-Stokes Raman lasing efficiency.

关键词： SRS Raman Low threshold anti-Stokes Raman laser on-chip Stokes

Risk of malignancy in Caroli disease and syndrome: A systematic review

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World Journal of Gastroenterology 2020年第31期26卷 4718-4728页

作者： rene Fahrner Sandra GC Dennler Daniel Inderbitzin Department of Surgery Bürgerspital SolothurnSolothurn 4500Switzerland Department of Surgery University Hospital DresdenDresden 01307Germany

BACKGROUND Congenital intrahepatic bile duct dilatation without fibrosis is called Caroli disease(CD),and is called Caroli syndrome(CS)when it has fibrotic and cirrhotic liver *** development of intrahepatic carcinoma is described in both conditions,but the reported incidence varies *** risk factors for the malignant transformation were not ***,conservative or surgical treatment is performed depending on the extent of cystic malformation,hepatic dysfunction and structural hepatic changes,but little is known about which treatment should be offered to patients with CD or CS and *** To further investigate the malignant transformation in these *** A systematic review of the current literature until January 2019 was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.A search using Medline(PubMed)was performed using a combination of Medical Subject Headings terms“caroli disease”,“caroli syndrome”,“tumor”,“malignant”,and“cholangiocarcinoma”.Only human studies published in English were used for this systematic *** following parameters were extracted from each article:year of publication,type of study,number of patients,incidence of malignant tumor,duration of symptoms,age,sex,diagnostics,identification of tumor,surgical therapy,survival and tumor *** Twelve retrospective studies reporting the courses of 561 patients(53%females)were included in this systematic *** a mean age of 41.6 years old(range 23 to 56 years old),patients were younger than other populations undergoing liver *** on the size of the study population the incidence of cholangiocarcinoma varied from 2.7%to 37.5%with an overall incidence of 6.6%.There were only few detailed reports about preoperative diagnostic work-up,but a multimodal work-up including ultrasound of the liver,computed tomography,magnetic resonance imaging and endoscopic retrograd

关键词： Malignancy Caroli disease Caroli syndrome Tumor Cholangiocarcinoma Review

Competition between Liquid-liquid De-mixing, Crystallization, and Glass Transition in Solutions of PLA of Different Stereochemistry and DEET

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Chinese Journal of Polymer Science 2020年第2期38卷 174-178,I0007页

作者： Chanita Sungkapreecha Walter WFocke rene Androsch Interdisciplinary Center for Transfer-oriented Research in Natural Sciences Martin Luther University Halle-Wittenberg06099 Halle/SaaleGermany University of Pretoria Institute for Sustainable Malaria Control and MRC Collaborating Centre for Malaria Research Department of Chemical EngineeringUniversity of PretoriaPrivate Bag X20Hatfield 0028South Africa

Liquid-liquid(L-L)de-mixing and vitrification of solutions of either crystallizable poly(L-lactic acid)(PLLA)or non-crystallizable poly(D/L-lactic acid)(PDLLA)with 50 m%N,N-diethyl-3-methylbenzamide(DEET)were analyzed by calorimetry and cloud-point measurements,which allows drawing conclusions about the effect of polymer stereochemistry on the phase *** of the PLA stereochemistry,vitrification of the solutions on fast cooling,hindering crystallization of PLLA,occurred below-20℃ and suppressed prior L-L *** experimental results prove that crystallization in samples containing crystallizable PLLA,observed at around 55℃ on slow cooling,is not preceded by L-L de-mixing.

关键词： Crystallization PLA DEET Liquid-liquid phase separation Thermally-induced phase separation(TIPS)

Continuous size fractionation of magnetic nanoparticles by using simulated moving bed chromatography

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Frontiers of Chemical Science and Engineering 2021年第5期15卷 1346-1355页

作者： Carsten-rene Arlt Dominik Brekel Stefan Neumann David Rafaja Matthias Franzreb Institute of Functional Interfaces Karlsruhe Institute of Technology76344Eggenstein-LeopoldshafenKarlsruheGermany Institute of Materials Science TU Bergakademie Freiberg09599FreibergGermany

The size fractionation of magnetic nanoparticles is a technical problem,which until today can only be solved with great ***,there is an important demand for nanoparticles with sharp size distributions,for example for medical technology or sensor *** magnetic chromatography,we show a promising method for fractionation of magnetic nanoparticles with respect to their size and/or magnetic *** was achieved by passing magnetic nanoparticles through a packed bed of fine steel spheres with which they interact magnetically because single domain ferro-/ferrimagnetic nanoparticles show a spontaneous *** the strength of this interaction is related to particle size,the principle is suitable for size *** concept was transferred into a continuous process in this work using a so-called simulated moving bed *** a suspension of magnetic nanoparticles within a size range from 20 to 120 nm,the process showed a separation sharpness of up to 0.52 with recovery rates of 100%.The continuous feed stream of magnetic nanoparticles could be fractionated with a space-time-yield of up to 5 mg/(L∙min).Due to the easy scalability of continuous chromatography,the process is a promising approach for the efficient fractionation of industrially relevant amounts of magnetic nanoparticles.

关键词： magnetic chromatography simulated moving bed chromatography magnetic nanoparticles size fractionation

Appendiceal endometriosis differentially diagnosed from acute appendicitis

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Chinese Medical Journal 2010年第12期123卷 1610-1611页

作者： Gaston Astroza Victor Faundes rene Nanjari Marcelo Fleiderman Carlos Rodriguez Servicio de Urgencia General Hospital Ramon Barros Luco Trudeau Santiago 8900085 Chile Servicio de Anatomfa Patologica Hospital Ramon Barros Luco Trudeau Santiago 8900085 Chile Escuela de Medicina Universidad de Chile Santiago 8380453 Chile Escuela de Medicina Universidad de Santiago de Chile Santiago 9170022 Chile

Endometriosis is a common disease in premenopausal women involving pelvic organs specially. Howeverendometriosis that affects the appendix is rarely seen except appendiceal endometriosis that mimics acute appendicitis. In a patient with acute appendicitis we diagnosed and operated on, histopathological examination of the appendix revealed appendiceal endometriosis which caused symptoms.

关键词： appendiceal endometriosis appendicitis

Epidemiology of co-infections in pregnant women living with human immunodeficiency virus 1 in rural Gabon:a cross-sectional study

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Infectious Diseases of Poverty 2023年第4期12卷 83-92页

作者： Saskia Dede Davi Dearie Glory Okwu Marc Luetgehetmann Frederique Mbang Abba Martin Aepfelbacher Lillian rene Endamne Ayodele Alabi Rella Zoleko-Manego Ghyslain Mombo-Ngoma Saidou Mahmoudou Marylyn Martina Addo Michael Ramharter Johannes Mischlinger Centre of Tropical Medicine Bernhard-Nocht Institute for Tropical Medicine and I.Department of MedicineUniversity Medical Center Hamburg-EppendorfHamburgGermany German Centre for Infection Research Partner Site Hamburg-Lübeck-Borstel-RiemsHamburg-Lübeck-Borstel-RiemsHamburgGermany Centre de Recherches Médicales de Lambaréné LambarénéGabon Saskia Dede DaviDearie Glory OkwuFrederique Mbang AbbaAyodele Center for Diagnostics Institute of Medical MicrobiologyVirology and HygieneUniversity Medical Center Hamburg-Eppendorf(UKE)HamburgGermany Albert-Schweitzer Hospital LambarénéGabon Department of Parasitology Leiden University Medical CenterAlbinusdreefThe Netherlands Department for Clinical Immunology of Infectious Diseases and I.Department of Medicine University Medical Center Hamburg-EppendorfHamburgGermany

Background There is no recent epidemiological data on HIV infection in Gabon,particularly in pregnant *** close this gap,an HIV-prevalence survey was conducted among Gabonese pregnant women,followed by a cross-sectional case-control study in which the prevalence of various co-infections was compared between HIV-positive and HIV-negative pregnant *** Between 2018 and 2019,data for the HIV-prevalence survey were collected retrospectively in 21 Gabonese antenatal care centres(ANCs).Subsequently,for the prospective co-infection study,all HIV-positive pregnant women were recruited who frequented the ANC in Lambarénéand a comparator sub-sample of HIV-negative pregnant women was recruited;these activities were performed from February 2019 to February *** mean number of coinfections was ascertained and compared between HIV-positive and HIV-negative ***,the odds for being co-infected with at least one co-infection was evaluated and compared between HIV-positive and HIV-negative *** HIV-positivity was 3.9%(646/16,417)among pregnant women.183 pregnant women were recruited in the co-infection study.63%of HIV-positive and 75%of HIV-negative pregnant women had at least one *** was a trend indicating that HIV-negative women were more often co-infected with sexually transmitted infections(STIs)than HIV-positive women[mean(standard deviation,SD):2.59(1.04)vs 2.16(1.35),respectively;P=0.056];this was not the case for vector-borne infections[mean(SD):0.47(0.72)vs 0.43(0.63),respectively;P=0.59].Conclusions Counterintuitively,the crude odds for concomitant STIs was lower in HIV-positive than in HIV-negative *** change of magnitude from the crude to adjustedOR is indicative for a differential sexual risk factor profile among HIV-positive and HIV-negative women in this *** might potentially be explained by the availability of sexual health care counselling for HIV-positive women within the framework of the nati

关键词： HIV Cross-sectional study Pregnancy Sexually transmitted infections Gabon

Innovation and Evaluation of Technology Acceptance Model (Tam) in S-Commerce: A Case of Social Media Platforms in Ghana

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Journal of Computer and Communications 2022年第3期10卷 100-124页

作者： Peprah rene Owusu Ennin Peter Asiedu Jiangming Ji Francis Atta Sarpong College of Information Technology Huzhou University Huzhou China School of Economics and Management Anhui University of Science and Technology Huainan China

Electronic commerce is quickly increasing in several countries, most notably in developing countries. A new electronic-commerce segment known as social commerce has evolved due to the popularity of social media. Consumer trust is important to social commerce success and impacts purchase choices. In modern times, majority of businesses have changed how from the traditional businesses and migrated to social commerce. Electronic commerce was the first of its sort, followed by social commerce, which conducted business via social networking platforms. Identifying the factors that influence social commerce use enables businesses to enhance those features and boost revenue. Thus, the purpose of this study was to examine how increased technology usage influences the social commerce activities of Ghanaian businessmen and women. A review of the literature resulted in the development of a conceptual model. Six hundred and twenty-five responses from Ghanaian enterprises and women who use e-commerce platforms were used to assess the conceptual approach. Partial Least Square Structural Equation Modeling (PLS SEM) was used to validate the model. The reliability and validity of the measuring apparatus were determined using measurement model analysis. To examine the model’s fit and assumptions, we used structural model analysis. Five hypotheses were supported by the structural model data. Effort Expectancy, Perceived Ease of Use, Performance Expectancy, Perceived Utility, and Trust were shown to be the most influential criteria affecting behavioral intention to use s-commerce in Ghana. The findings of this research have major significance for academics and practitioners of social trade.

关键词： Technology Acceptance Model (TAM) Smart PLS SEM Social Commerce Electronic Commerce