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External Electric Field Effect on Electrons Transport in Carbon Nanotubes

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World Journal of Condensed Matter Physics 2013年第4期3卷 169-172页

作者： Sulemana S. Abukari Samuel Y. Mensah Musah Rabiu Kofi W. Adu Natalia G. Mensah Kwadwo A. Dompreh Anthony Twum matthew amekpewu Department of Applied Physics University for Development Studies Navorongo Ghana Department of Mathematics University of Cape Coast Cape Coast Ghana Department of Physics Laser and Fibre Optics Centre University of Cape Coast Cape Coast Ghana Department of Physics The Pennsylvania State University Altoona USA Materials Research Institute The Pennsylvania State University University Park USA

We consider a simple model of carbon nanotubes (CNTs) subject to external electric field E(t). Using a tight-binding approximation for the description of energy bands of CNTs, together with the standard Boltzmann transport equation and constant relaxation time, we predict the effect of self-induced transparency and absolute negative conductivity. The predicted effects may be useful in diagnostics of carbon nanotubes as well as in the amplification and efficiency conversion of electromagnetic signals.

关键词： Carbon Nanotubes Electric Field Electric Current Density Negative Differential Conductivity

High-Frequency Electric Field Induced Nonlinear Electron Transport in Chiral Carbon Nanotubes

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World Journal of Condensed Matter Physics 2015年第4期5卷 294-300页

作者： Sulemana S. Abukari Samuel Y. Mensah Musah Rabiu Kofi W. Adu Natalia G. Mensah Anthony Twum Alfred Owusu Kwadwo A. Dompreh Patrick Mensah-Amoah matthew amekpewu Department of Physics Laser and Fibre Optics Centre University of Cape Coast Cape Coast Ghana Department of Applied Physics University for Development Studies Navorongo Ghana Department of Physics The Pennsylvania State University-Altoona Altoona USA Materials Research Institute The Pennsylvania State University University Park USA Department of Mathematics University of Cape Coast Cape Coast Ghana

We investigate theoretically the high frequency complex conductivity in carbon nanotubes that are stimulated axially by a strong inhomogeneous electric field of the form E(t)=E0+E1cos(ωt). Using the kinetic approach based on Boltzmann’s transport equation with constant relaxation time approximation and the energy spectrum of the electron in the tight-binding approximation, together with Bhatnagar-Gross-Krook collision integral, we predict high-frequency nonlinear effects along the axial and the circumferential directions of the carbon nanotubes that may be useful for the generation of high frequency radiation in the carbon nanotubes.

关键词： Carbon Nanotubes High Frequency Electric Field Electric Current Density Complex Conductivity

Domain Suppression in the Negative Differential Conductivity Region of Carbon Nanotubes by Applied AC Electric Field

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World Journal of Condensed Matter Physics 2012年第4期2卷 274-277页

作者： Sulemana S. Abukari Samuel Y. Mensah Kofi W. Adu Natalia G. Mensah Kwadwo A. Dompreh Anthony Twum Chales L. Y. Amuah matthew amekpewu Musah Rabiu Department of Applied Physics University for Development Studies Navorongo Ghana Department of Physics Laser and Fibre Optics Centre University of Cape Coast Cape Coast Ghana Department of Physics The Pennsylvania State University Altoona USA Materials Research Institute The Pennsylvania State University University Park USA National Centre for Mathematical Sciences Ghana Atomic Energy Commission Accra Ghana Department of Mathematics University of Cape Coast Cape Coast Ghana

We study theoretically the electron transport properties in achiral carbon nanotubes under the influence of an external electric field E(t) using Boltzmann’s transport equation to derive the current-density. A negative differential conductivity (NDC) is predicted in quasi-static approximation i.e., ωτ 0 is equal to the amplitude of the AC electric field E1. The peak of the NDC intensity occurs at very weaker fields than that of superlattice under the same conditions. The peak intensity decreases and shifts to right with the increase in the amplitude of the ac field. This mechanism suppresses the domain formation and therefore could be used in terahertz frequency generation.

关键词： Carbon Nanotubes Negative Differential Conductivity and Generation of Terahertz Radiation

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： Christopher J.O’Connell matthew J.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA James L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain injury(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

Machine learning in solid organ transplantation:Charting the evolving landscape

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World Journal of Transplantation 2025年第1期15卷 165-177页

作者： Badi Rawashdeh Haneen Al-abdallat Emre Arpali Beje Thomas Ty B Dunn matthew Cooper Division of Transplant Surgery Medical College of WisconsinMilwaukeeWI 53202United States Department of Medicine Jordan University HospitalAmman 11263Jordan Department of Nephrology Medical College of WisconsinMilwaukeeWI 53226United States

BACKGROUND Machine learning(ML),a major branch of artificial intelligence,has not only demonstrated the potential to significantly improve numerous sectors of healthcare but has also made significant contributions to the field of solid organ *** provides revolutionary opportunities in areas such as donorrecipient matching,post-transplant monitoring,and patient care by automatically analyzing large amounts of data,identifying patterns,and forecasting *** To conduct a comprehensive bibliometric analysis of publications on the use of ML in transplantation to understand current research trends and their *** On July 18,a thorough search strategy was used with the Web of Science *** and transplantation-related keywords were *** the aid of the VOS viewer application,the identified articles were subjected to bibliometric variable analysis in order to determine publication counts,citation counts,contributing countries,and institutions,among other *** Of the 529 articles that were first identified,427 were deemed relevant for bibliometric analysis.A surge in publications was observed over the last four years,especially after 2018,signifying growing interest in this *** 209 publications,the United States emerged as the top ***,the"Journal of Heart and Lung Transplantation"and the"American Journal of Transplantation"emerged as the leading journals,publishing the highest number of relevant *** keyword searches revealed that patient survival,mortality,outcomes,allocation,and risk assessment were significant themes of *** The growing body of pertinent publications highlights ML's growing presence in the field of solid organ *** bibliometric analysis highlights the growing importance of ML in transplant research and highlights its exciting potential to change medical practices and enhance patient *** collaboration between signific

关键词： Machine learning Artificial Intelligence Solid organ transplantation Bibliometric analysis

Complement-dependent neuroinflammation in spinal cord injury:from pathology to therapeutic implications

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Neural Regeneration Research 2025年第5期20卷 1324-1335页

作者： Hassan Saad Bachar El Baba Ali Tfaily Firas Kobeissy Juanmarco Gutierrez Gonzalez Daniel Refai Gerald R.Rodts Christian Mustroph David Gimbel Jonathan Grossberg Daniel L.Barrow matthew F.Gary Ali M.Alawieh Department of Neurosurgery Emory University School of MedicineAtlantaGAUSA Department of Neurology Yale UniversityNew HavenCTUSA Center for Neurotrauma Multiomics&Biomarkers(CNMB)Morehouse School of MedicineAtlantaGAUSA

Spinal cord injury remains a major cause of disability in young adults,and beyond acute decompression and rehabilitation,there are no pharmacological treatments to limit the progression of injury and optimize recovery in this *** the thorough investigation of the complement system in triggering and propagating cerebral neuroinflammation,a similar role for complement in spinal neuroinflammation is a focus of ongoing *** this work,we survey the current literature investigating the role of complement in spinal cord injury including the sources of complement proteins,triggers of complement activation,and role of effector functions in the *** study relevant data demonstrating the different triggers of complement activation after spinal cord injury including direct binding to cellular debris,and or activation via antibody binding to damage-associated molecular *** effector functions of complement have been implicated in spinal cord injury,and we critically evaluate recent studies on the dual role of complement anaphylatoxins in spinal cord injury while emphasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord *** this pathophysiological review,we systematically review the different translational approaches used in preclinical models of spinal cord injury and discuss the challenges for future translation into human *** review emphasizes the need for future studies to dissect the roles of different complement pathways in the pathology of spinal cord injury,to evaluate the phases of involvement of opsonins and anaphylatoxins,and to study the role of complement in white matter degeneration and regeneration using translational strategies to supplement genetic models.

关键词： complement neuroinflammation neuroplasticity regeneration spinal cord injury targeted therapy

A MONOTONE DOMAIN DECOMPOSITION ALGORITHM FOR SOLVING WEIGHTED AVERAGE APPROXIMATIONS TO NONLINEAR SINGULARLY PERTURBED PARABOLIC PROBLEMS

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Journal of Computational Mathematics 2008年第1期26卷 76-97页

作者： Igor Boglaev matthew Hardy Institute of Fundamental Sciences Massey UniversityPrivate Bag 11-222Palmerston NorthNew Zealand Mathematical Sciences Institute Australian National UniversityCanberraAustralia 0200

This paper presents and analyzes a monotone domain decomposition algorithm for solving nonlinear singularly perturbed reaction-diffusion problems of parabolic type. To solve the nonlinear weighted average finite difference scheme for the partial differential equation, we construct a monotone domain decomposition algorithm based on a Schwarz alternating method and a box-domain decomposition. This algorithm needs only to solve linear discrete systems at each iterative step and converges monotonically to the exact solution of the nonlinear discrete problem. domain decomposition algorithm is estimated The rate of convergence of the monotone Numerical experiments are presented.

关键词： Parabolic reaction-diffusion problem Boundary layers O-method Monotone domain decomposition algorithm Uniform convergence

Hepatocellular carcinoma recurrence after liver transplant:An Australian single-centre study

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World Journal of Transplantation 2025年第1期15卷 105-114页

作者： matthew G Garas Luis Calzadilla-Bertot Briohny W Smith Luc Delriviere Byron Jaques Lingjun Mou Leon A Adams Gerry C MacQuillan George Garas Gary P Jeffrey Michael C Wallace Medical School University of Western AustraliaNedlands 6009Western AustraliaAustralia Department of Hepatology Sir Charles Gairdner HospitalNedlands 6009Western AustraliaAustralia Department of Surgery Sir Charles Gairdner HospitalNedlands 6009Western AustraliaAustralia

BACKGROUND Hepatocellular carcinoma(HCC)is a leading cause of cancer-related deaths *** transplantation(LT)offers the most effective *** recurrence is the strongest risk factor that decreases post-LT survival in patients transplanted for *** rate of HCC recurrence is generally reported as 8%-20%in the *** predictors of HCC have already been researched,however,to our knowledge there are no published studies on this topic using Australian *** To determine the rate and identify predictors of HCC recurrence in a contemporary Western Australian LT *** We performed a retrospective cohort study of all liver transplants in patients with HCC at Sir Charles Gairdner Hospital between 2006 and *** was collected from various health record databases and included recipient demographics,serum biochemistry,radiology,operation notes,explant histopathology and details of *** survival of HCC patients post-LT,stratified for recurrence,was calculated by Kaplan Meier *** and multivariate Cox regression was used to determine predictors of HCC recurrence *** Between 1/1/2006 and 12/31/2021,119 patients were transplanted with HCC.8.4%of subjects developed recurrent HCC after LT with median follow-up time of 5.4 *** median time to recurrence was 2.9 years±0.75 *** comparing baseline characteristics,a greater proportion of subjects with recurrence had common characteristics on explant histopathology,including>3 viable nodules(P=0.001),vascular invasion(P=0.003)and poorly differentiated HCC(P=0.03).Unadjusted survival curves showed lower 1-year,3-year,5-year and 10-year survival rates in subjects with HCC recurrence compared to those without HCC recurrence(90%vs 92%,70%vs 88%,42%vs 80%,14%vs 76%,respectively;log rank P<0.001).CONCLUSION HCC recurrence was low at 8.4%in this contemporary Australian cohort,however it significantly impacted post-LT *** studies are requir

关键词： Liver cancer Recurrence Liver transplantation Hepatocellular carcinoma Predictors Post-transplant survival Australian data

Schreibersite on the early Earth:Scenarios for prebiotic phosphorylation

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Geoscience Frontiers 2017年第2期8卷 329-335页

作者： matthew A.Pasek School of Ceoscience University of South FloridaTampaFL 33620USA

The mineral schreibersite,（Fe,Ni）_3P,provides a reactive source of phosphorus capable of forming phosphorylated *** molecules may have been an important component of prebiotic chemistry,allowing their build-up and eventual commencement of *** here are potential geochemical routes to providing schreibersite,as a potentially important prebiotic mineral,to the Hadean *** routes are identified：delivery of phosphides by meteoritic material and the reduction of phosphates to phosphides by high-temperature,low-redox *** 1-10% of all crustal phosphorus is estimated to have been in schreibersite during the Hadean,making the long-term reaction of this mineral with organic-laden water plausible for many ***,such conditions would have been conducive to the formation of life as we know it today.

关键词： Phosphorus Hadean Meteorites Thermodynamics Origin of life Prebiotic chemistry