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Impact of device resistances in the performance of graphene‑based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期17卷 87-97页

作者： O.Castelló Sofía M.López Baptista K.Watanabe T.Taniguchi E.Diez j.E.velázquez-Pérez Y.M.Meziani j.M.Caridad j.A.Delgado-Notario Department of Applied Physics University of Salamanca37008 SalamancaSpain Unidad de Excelencia en Luz y Materia Estructurada(LUMES) University of Salamanca37008 SalamancaSpain Research Center for Electronic and Optical Materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for Materials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Nanotechnology Group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(GFETs)have demonstrated an outstanding potential for terahertz(THz)photodetection due to their fast response and *** features are essential to enable emerging THz applications,including 6G wireless communications,quantum information,bioimaging and ***,the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device,so-called access or parasitic *** this work,we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFET *** dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector,*** results can be well understood by a series resistance model,as shown by the excellent agreement found between the experimental data and theoretical *** findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

关键词： Graphene THz Photodetector Field-effect transistor Plasmonic

Clinical and Demographic Profile of Women with Uterine Fibroids Living in Puerto Rico

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Open j.urnal of Obstetrics and Gynecology 2024年第9期14卷 1347-1362页

作者： Edwin Y. Soto-velázquez Alexander j. j.ramillo-Cañas Shania N. Aponte-Paris Gabriela V. Martínez-Marrero Irazu S. Guinan Gabrielle A. Rivera-Maldonado Alexandra Novas Pedro L. Cruz-Rosa Idhaliz Flores-Caldera Maricarmen Colón-Diaz Department of Physiology and Pathology San Juan Bautista School of Medicine Caguas Puerto Rico United States Ponce Research Institute Ponce Health Sciences University Ponce Puerto Rico United States

Introduction: Uterine leiomyomas, or fibroids, are prevalent benign tumors affecting up to 70% of reproductive-age women in the United States, significantly impacting productivity and quality of life. Despite their commonality, the epidemiology and clinical patterns of leiomyomas in Puerto Rico remain inadequately researched. Methods: This study conducted a secondary data analysis using clinical, menstrual cycle characteristics, and demographic data from self-administered questionnaires of women undergoing diagnostic laparoscopy for endometriosis in Puerto Rico. Chi-square tests and t-tests analyzed categorical and continuous variables, respectively (p Results: Among 1,610 endometriosis cases, 312 included uterine fibroids. Prevalence estimates were 10.3% (40 years). Primiparous women averaged 22.14 years, with 40.71% having 2 - 3 pregnancies and 26.28% experiencing miscarriages. Symptoms included infertility (29.5%), dyspareunia (40.7%), severe pain (50%), and dysmenorrhea (75.6%). Comorbidities included ovarian cysts (52.2%) and abnormal uterine bleeding (37.8%). Conclusions: Advanced age, parity, and comorbidities like diabetes and hypertension were prevalent in our cohort. Understanding the epidemiological profile of women living in Puerto Rico with uterine fibroids is crucial for improving diagnostic awareness and enhancing patient care.

关键词： Uterine Fibroids Puerto Rico Epidemiology Dysmenorrhea Abnormal Uterine Bleeding

Contribution of national bioassessment approaches for assessing ecological water security： an AUSRIVAS case study

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Frontiers of Environmental Science & Engineering 2013年第5期7卷 669-687页

作者： susan j. NICHOLS Fiona j. DYER Institute for Applied Ecology and MDBfutures CRN University of Canberra Canberra ACT 2601 Australia

River managers in Australia are managing in the face of extremes to provide security of water supply for people, production and the environment. Balancing the water requirements of people, environments and econo- mies requires that water security is viewed holistically, not j.st in terms of the water available for human consump- tion. Common definitions of water security focus on the needs of both humans and ecosystems for purposes such as drinking, agriculture and industrial use, and to maintain ecological values. Information about achieving water security for the environment or ecological purposes can be a challenge to interpret because the watering require- ments of key ecological processes or assets are not well understood, and the links between ecological and human values are often not obvious to water users. Yet the concepts surrounding river health are inherently linked to holistic concepts of water security. The measurement of aquatic biota provides a valuable tool for managers to understand progress toward achieving ecological water security obj.ctives. This paper provides a comprehensive review of the reference condition approach to river health assessment, using the development of the Australian River Assessment System （AUSRIVAS） as a case study. We make the link between the biological assessment of river health and assessment of ecological water security, and suggest that such an approach provides a way of reporting that is relevant to the contribution made by ecosystems to water security. The reference condition approach, which is the condition representative of minimally disturbed sites organized by selected physical, chemical, and biological characteristics, is most important for assessing ecological water security obj.ctives.

关键词： ecological water security biological assessment river health

Pre-operative visceral adipose tissue radiodensity is a potentially novel prognostic biomarker for early endoscopic post-operative recurrence in Crohn’s disease

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World j.urnal of Gastrointestinal Surgery 2024年第3期16卷 740-750页

作者： Phillip Gu Shishir Dube Norman Gellada So Yung Choi susan Win Yoo j.n Lee Shaohong Yang Talin Haritunians Gil Y Melmed Eric A Vasiliauskas Niru Bonthala Gaurav Syal Andres j.Yarur David Ziring Shervin Rabizadeh Phillip Fleshner Cindy Kallman Suzanne Devkota Stephan R Targan Dalin Li Dermot PB McGovern Department of Medicine Cedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Imaging Cedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Biostatistics Shared Resource Cedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Internal Medicine Keimyung University School of MedicineDaegu 42601South Korea Department of Medicine University of California at Los AngelesLos AngelesCA 90095United States Department of Medicine University of California at San DiegoSan DiegoCA 92093United States Department of Pediatrics Cedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Surgery Cedars-Sinai Medical CenterLos AngelesCA 90048United States

BACKGROUND Evidence suggests inflammatory mesenteric fat is involved in post-operative recurrence(POR)of Crohn’s disease(CD).However,its prognostic value is INTRODUCTION Crohn’s disease(CD)is a debilitating chronic immune-mediated inflammatory disease(IMID)of the gastrointestinal tract that is increasing in incidence and prevalence globally[1].CD patients often undergo surgery for disease-related complic-ations and/or medically refractory ***,surgery is not curative,and many patients develop post-operative recurrence(POR)of CD with a significant proportion eventually requiring additional *** advances in early detection and therapeutics,the contemporary 10-year risk of surgery has improved from 50%to 26%,but the risk of recurrent surgery has remained unchanged at 30%,suggesting a need to improve post-operative management strategies[2].Presently,there are two accepted strategies to mitigate POR,but each have potential ***,patients start early post-operative pharmacologic prophylaxis within 4-6 wk after *** strategy can potentially overtreat a subset of patient who may not develop long-term disease recurrence off ***,these patients are at risk of medication-related adverse events and the direct and indirect costs associated with therapy with little or no benefit[3].The second strategy is performing early colonoscopy within 6-12 months after surgery and escalating therapy based on FOOTNOTES Author contributions:Gu P is the guarantor of the article and was involved in concept and design,data collection,statistical analysis,drafting of manuscript,and final approval of manuscript;Dube S and Choi SY were involved in statistical analysis,drafting of the manuscript,and final approval of manuscript;Gellada N,Win S,Lee Yj.and Yang S were involved in the data collection,drafting of the manuscript,and final approval of manuscript;Haritunians T and Li D were involved in data analysis and interpretation,drafting

关键词： Crohn’s disease Surgery Visceral adipose tissue Mesenteric adipose tissue Creeping fat Computed tomography

Cell Wall Microstructure Analysis Implicates Hemicellulose Polysaccharides in Cell Adhesion in Tomato Fruit Pericarp Parenchyma

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Molecular Plant 2009年第5期2卷 910-921页

作者： j.se j. Ordaz-Ortiz susan E. Marcus j. Paul Knox Centre for Plant Sciences Faculty of Biological Sciences University of Leeds Leeds LS2 9JT United Kingdom

Methods developed to isolate intact cells from both unripe and ripe tomato fruit pericarp parenchyma have allowed the cell biological analysis of polysaccharide epitopes at the surface of separated cells. The LM7 pectic homogalacturonan epitope is a marker of the j.nctions of adhesion planes and intercellular spaces in parenchyma systems. The LM7 epitope persistently marked the former edge of adhesion planes at the surface of cells separated from unripe and ripened tomato fruit and also from fruits with the Cnr mutation. The LM 11 xylan epitope was associated, in sections, with cell walls lining intercellular space but the epitope was not detected at the surface of isolated cells, being lost during cell isolation. The LM15 xyloglucan epitope was present at the surface of cells isolated from unripe fruit in a pattern reflecting the former edge of cell adhesion planes/intercellular space but with gaps and apparent breaks. An equivalent pattern of LM15 epitope occurrence was revealed at the surface of cells isolated by pectate lyase action but was not present in cells isolated from ripe fruit or from Cnr fruit. In contrast to wild-type cells, the LM5 galactan and LM21 mannan epitopes occurred predominantly in positions reflecting intercellular space in Cnr, suggesting a concerted alteration in cell wall microstructure in response to this mutation. Galactanase and mannanase, along with pectic homogalacturonan-degrading enzymes, were capable of releasing cells from unripe fruit parenchyma. These observations indicate that hemicellulose polymers are present in architectural contexts reflecting cell adhesion and that several cell wall polysaccharide classes are likely to contribute to cell adhesion/cell separation in tomato fruit pericarp parenchyma.

关键词： Cell walls fruit development tomato cell adhesion cell separation polysaccharide.

Improved Interleaved Single-Ended Primary Inductor-Converter forSingle-Phase Grid-Connected System

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Intelligent Automation & Soft Computing 2023年第3期35卷 3459-3478页

作者： T.j.Thomas Thangam K.Muthu vel Noorul Islam Centre for Higher Education Nagarkovil629180TamilnaduIndia

The generation of electricity based on renewable energy sources,parti-cularly Photovoltaic(PV)system has been greatly increased and it is simply insti-gated for both domestic and commercial *** power generated from the PV system is erratic and hence there is a need for an efﬁcient converter to perform the extraction of maximum *** improved interleaved Single-ended Primary Inductor-Converter(SEPIC)converter is employed in proposed work to extricate most of power from renewable *** proposed converter minimizes ripples,reduces electromagnetic interference due toﬁlter elements and the contin-uous input current improves the power output of PV panel.A Crow Search Algo-rithm(CSA)based Proportional Integral(PI)controller is utilized for controlling the converter switches effectively by optimizing the parameters of PI *** optimized PI controller reduces ripples present in Direct Current(DC)vol-tage,maintains constant voltage at proposed converter output and reduces over-shoots with minimum settling and rise *** voltage is given to single phase grid via 1�Voltage Source Inverter(VSI).The command pulses of 1�VSI are produced by simple PI *** response of the proposed converter is thus improved with less input *** implementing CSA based PI the efﬁciency of proposed converter obtained is 96%and the Total Harmonic Distor-tion(THD)is found to be 2:4%.The dynamics and closed loop operation is designed and modeled using MATLAB Simulink tool and its behavior is performed.

关键词： Improved interleaved DC-DC SEPIC converter crow search algorithm PI controller voltage source inverter PV array single phase grid

Using classification assignment rules to assess land-use change impacts on forest biodiversity at local-to-national scales

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Forest Ecosystems 2018年第2期5卷 162-176页

作者： Kathrin Affeld susan K. Wiser Ian j. Payton Miquel DeCaceres Manaaki Whenua - Landcare Research PO Box 69040 Lincoln 7640 New Zealand Lincoln University PO Box 85084 Lincoln 7647 New Zealand Forest Science Centre of Catalonia Ctra. Sant Llorenc km.2 E-25280 Solsona Spain

Background： Ecosystem representation is one key component in assessing the biodiversity impacts of land-use changes that will irrevocably alter natural ecosystems. We show how detailed vegetation plot data can be used to assess the potential impact of inundation by a proposed hydroelectricity dam in the Mokihinui gorge, New Zealand, on representation of natural forests. Specifically we ask： 1） How well are the types of forest represented Locally, regionally, and nationally; and 2） How does the number of distinct communities （i.e. beta diversity） in the target catchment compare with other catchments nationally？ Methods： For local and regional comparisons plant species composition was recorded on 45 obj.ctively located 400 m2 vegetation plots established in each of three gorges, with one being the proposed inundation area of the Mokihinui lower gorge. The fuzzy classification framework of noise clustering was used to assign these plots to a specific alliance and association of a pre-existing national-scale classification. NationaLly, we examined the relationship between the number of alliances and associations in a catchment and either catchment size or the number of plots per catchment by fitting Generalised Additive Models. Results： The four alliances and five associations that were observed in the Mokihinui lower gorge arepresent in the region but limited locally. One association was narrowly distributed nationally, but is the mostfrequent association in the Mokihinui lower gorge; inundation may have consequences of national importance to its long-term persistence. That the Mokihinui lower gorge area had nearly twice as many plots that could not be assigned to pre- existing alliances and associations than either the Mokihinui upper or the Karamea lower gorges and proportionally more than the national dataset emphasises the compositional distinctiveness of this gorge. These outlier plots in the Mokihinui lower gorge may be unsorted assemblages of species or reflect

关键词： Beta-diversity Biodiversity conservation Environmental impacts Ecosystem representation Hydroelectricity dams Land-use change National vegetation classification Noise clustering New Zealand NVS databank Plant community composition

The effect of temperature on ionic liquid modified Fe-N-C catalysts for alkaline oxygen reduction reaction

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j.urnal of Energy Chemistry 2022年第5期31卷 324-329页

作者： Thomas Wolker Kai Brunnengräber Ioanna Martinaiou Nick Lorenz Gui-Rong Zhang Ulrike I.Kramm Bastian j.M.Etzold Department of Chemistry Ernst-Berl-Institut für Technische und Makromolekulare ChemieTechnical University of Darmstadt64287 DarmstadtGermany Department of Chemistry Catalysts and Electrocatalysts GroupTechnical University of Darmstadt64287 DarmstadtGermany Graduate School of Excellence Energy Science and Engineering Technical University of Darmstadt64287 DarmstadtGermany Department of Materials and Earth Sciences Technical University of Darmstadt64287 DarmstadtGermany School of Chemical Engineering and Technology Tiangong UniversityTianjin 300387China

Modifying solid catalysts with an ionic liquid layer is an effective approach for boosting the performance of both Pt-based and non-precious metal catalysts toward the oxygen reduction reaction. While most studies operated at room temperature it remains unclear whether the IL-associated boosting effect can be maintained at elevated temperature, which is of high relevance for practical applications in low temperature fuel cells. Herein, Fe-N-C catalysts were modified by introducing small amounts of hydrophobic ionic liquid, resulting in boosted electrocatalytic activity towards the alkaline oxygen reduction reaction at room temperature. It is demonstrated that the boosting effect can be maintained and even strengthened when increasing the electrolyte temperature up to 70℃. These findings show for the first time that the incorporation of ionic liquid is a suited method to obtain advanced noble metal-free electrocatalysts that can be applied at operating temperature condition.

关键词： Oxygen reduction reaction Non-precious metal catalyst Ionic liquid Fe-N-C catalyst Temperature effect

Double Fertilization in Arabidopsis thaliana Involves a Polyspermy Block on the Egg but Not the Central Cell

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Molecular Plant 2008年第4期1卷 611-619页

作者： Rod j. Scott susan j. Armstrong j.mes Doughty Melissa Spielman Department of Biology and Biochemistry University of Bath Claverton Down Bath BA2 7AY United Kingdom School of Biosciences The University of Birmingham Edgbaston Birmingham B15 2TT United Kingdom

In animal reproduction, thousands of sperm may compete to fertilize a single egg, but polyspermy blocks prevent multiple fertilization that would otherwise lead to death of the embryo. In flowering plants, successful seed development requires that only two sperm are delivered to the embryo sac, where each must fertilize a female gamete （egg or central cell） to produce the embryo and endosperm. Therefore, polyspermy must be avoided, not only to prevent abnormalities in offspring, but to ensure double fertilization. It is not understood how each sperm fertilizes only one female gamete, nor has the existence of polyspermy barriers been directly tested in vivo. Here, we sought evidence for poly- spermy blocks in angiosperms using the polyspermic tetraspore （tes） mutant of Arabidopsis, which allows in-vivo challenge of egg and central cell with multiple male gametes. We show that tes mutant pollen tubes can transmit more than one sperm pair to an embryo sac, and that sperm from more than one pair can participate in fertilization. We detected endosperms but not embryos with ploidies that could only result from multiple fertilization. Our results therefore demonstrate an in-vivo polyspermy block on the egg, but not the central cell of a flowering plant.

关键词： Ovum Embryo Ploidies Endosperm Arabidopsis thaliana embryo sac Spermatozoa fertilizer application polyspermy flowering plant Eggs Fertilization