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Light(Science & Applications) 2016年第1期5卷 737-743页

作者： Peter P Vasil’ev richard V Penty Ian H White Centre for Photonic Systems Department of EngineeringUniversity of CambridgeCambridge CB30FAUK Quantum Electronics Division PN Lebedev Physical InstituteMoscow 119991Russia

This paper reports the observation of ultra-superluminal pulse propagation in multiple-contact semiconductor heterostructures in a superradiant emission regime,and shows definitively that it is a different class of emission from conventional spontaneous or stimulated *** population gratings induced in the semiconductor medium under strong electrical pumping have been shown to cause a major decrease of the group refractive index,in the range of 5–40%.This decrease is much greater than that caused by conventional carrier depletion or chirp *** decrease in refractive index in turn causes faster-than-c propagation of femtosecond *** measurement also proves the existence of coherent amplification of electromagnetic pulses in semiconductors at room temperature,the coherence being strongly enhanced by interactions of the light with coherent transient gratings locked to carrier *** pulse-generation technique is anticipated to have great potential in applications where highly coherent femtosecond optical pulses must be generated on demand.

关键词： phase transition population grating superradiance superluminal propagation

MicroRNAs:new players in the DNA damage response

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Journal of Molecular Cell Biology 2011年第3期3卷 151-158页

作者： Hailiang Hu richard A.Gatti Department of Pathology and Laboratory Medicine David Geffen School of Medicine at UCLALos AngelesCA 90095-1732USA Department of Human Genetics David Geffen School of Medicine at UCLALos AngelesCA 90095-1732USA

The DNA damage response(DDR)is a signal transduction pathway that decides the cell’s fate either to repair DNA damage or to undergo apoptosis if there is too much ***-translational modifications modulate the assembly and activity of protein complexes during the DDR ***(miRNAs)are emerging as a class of endogenous gene modulators that control protein levels,thereby adding a new layer of regulation to the *** this review,we describe a new role for miRNAs in regulating the cellular response to DNA damage with a focus on DNA double-strand break *** also discuss the implications of miRNA’s role in the DDR to stem cells,including embryonic stem cells and cancer stem cells,stressing the potential applications for miRNAs to be used as sensitizers for cancer radiotherapy and chemotherapy.

关键词： microRNA DNA damage response radiosensitivity stem cells

Emerging therapeutic options for the management of hepatitis C infection

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World Journal of Gastroenterology 2014年第23期20卷 7079-7088页

作者： J richard Thompson Department of Pharmacy Practice One University Park DriveLipscomb University College of PharmacyNashvilleTN 37204United States

Until recently the traditional treatment for hepatitis C infection included pegylated interferon and ribavirin combination *** sustained virological response(SVR)seen with this combination is poor and requires lengthy treatment to ***,significant side effects and numerous contraindications prevented many patients from being successfully treated with this *** 2011,two new protease inhibitors,telaprevir and boceprevir,were approved for use with pegylated interferon and ribavirin in the United States by the United States Food and Drug *** agents have significantly improved SVR rates;however significant problems with toxicity remain including severe skin rash and *** are a wide range of compounds in late stage development for the future treatment of hepatitis C that exploit many different mechanisms of viral *** of these compounds include additional protease inhibitors,like telaprevir and boceprevir,as well as inhibitors of other nonstructural proteins in the viral genome such as ns5A and ns5B,and compounds that target host proteins within the *** of these agents are being developed for oral administration once daily and various combinations are being assessed for use without the need for pegylated interferon and *** paper reviews agents in late phase development that may be commercially available within 1-2 years.

关键词： Hepatitis C Pharmacotherapy Interferon Ribavirin Protease inhibitors Polymerase inhibitors Cyclophilin inhibitors

Electro-oxidation of hydrazine shows marcusian electron transfer kinetics

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Science China Chemistry 2021年第2期64卷 322-329页

作者： Ruiyang Miao Lifu Chen richard G Compton Department of Chemistry Physical and Theoretical Chemistry LaboratoryUniversity of OxfordSouth Parks RoadOxfordOX13QZUK

Although hydrazine(N2 H4) oxidation in an electrochemical environment has been of great interest for years,its intrinsic electron transfer kinetics remain *** report that the phenomenological Butler-Volmer(BV) theory is not appropriate for interpreting the process of hydrazine oxidation for which an astonishingly wide range of transfer coefficients,Tafel slopes and diffusion coefficient have been previously *** Tafel analysis for voltammetry recorded at Glassy Carbon(GC)electrodes reveals a strong potential dependence of the anodic transfer coefficient,consistent with the symmetric Marcus-Hush(sMH) *** to the relationship β=λ+FEf^0/2λ-F/2λ E,the reorganization energy(0.35±0.07 ev) and an approximate formal potential of the rate-determining first electron transfer were successfully extracted from the voltammetric responses.

关键词： hydrazine electrode kinetics transfer coefficient Butler-Volmer theory Marcus-Hush theory

The importance of laminin at the blood-brain barrier

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Neural Regeneration Research 2023年第12期18卷 2557-2563页

作者： Sebok K.Halder Arjun Sapkota richard Milner San Diego Biomedical Research Institute San DiegoCAUSA

The blood-brain barrier is a unique property of central nervous system blood vessels that protects sensitive central nervous system cells from potentially harmful blood *** mechanistic basis of this barrier is found at multiple levels,including the adherens and tight junction proteins that tightly bind adjacent endothelial cells and the influence of neighboring pericytes,microglia,and astrocyte *** addition,extracellular matrix components of the vascular basement membrane play a critical role in establishing and maintaining blood-brain barrier integrity,not only by providing an adhesive substrate for blood-brain barrier cells to adhere to,but also by providing guidance cues that strongly influence vascular cell *** extracellular matrix protein laminin is one of the most abundant components of the basement membrane,and several lines of evidence suggest that it plays a key role in directing blood-brain barrier *** this review,we describe the basic structure of laminin and its receptors,the expression patterns of these molecules in central nervous system blood vessels and how they are altered in disease states,and most importantly,how genetic deletion of different laminin isoforms or their receptors reveals the contribution of these molecules to blood-brain barrier function and ***,we discuss some of the important unanswered questions in the field and provide a“to-do”list of some of the critical outstanding experiments.

关键词： astrocytes basement membrane blood vessels blood-brain barrier integrity dystroglycan endothelial cells inflammation integrins laminin pericytes

AC Impedance Behaviour of Black Diamond Films

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Journal of Materials Science & Technology 2005年第6期21卷 879-882页

作者： Olivier GAUDIN richard B.JACKMAN Electronic and Electrical Engineering University College London Torrington Place London WC1E 7JE UK

The first measurement of impedance on free-standing diamond films from 0.1 Hz to 10 MHz up to 300℃ were reported. A wide range of chemical vapour deposition （CVD） materials were investigated, but here we concentrate on ‘black＇ diamond grown by microwave plasma enhanced CVD （MWPECVD）. The Cole-Cole （Z′ via Z″） plots are well fitted to a RC parallel circuit model and the equivalent resistance and capacitance for the diamond films have been estimated using the Zview curve fitting. The results show only one single semicircle response at each temperature measured. It was found that the resistance decreases from 62 MΩ at room temperature to 4 kΩ at 300℃, with an activation energy around 0.51 ev. The equivalent capacitance is maintained at the level of 100 pF up to 300℃ suggesting that the diamond grain boundaries are dominating the conduction. At 400℃, the impedance at low frequencies shows a linear tail, which can be explained that the AC polarization of diamond/Au interface occurs.

关键词： Black diamond Impedance spectroscopy Activation energy

From Neurons to Cognition:Technologies for Precise Recording of Neural Activity Underlying Behavior

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Biomedical Engineering Frontiers 2020年第1期1卷 64-83页

作者： richard H.Roth Jun B.Ding Department of Neurosurgery Stanford UniversityStanfordCA 94305USA Department of Neurology and Neurological Sciences Stanford UniversityStanfordCA 94305USA

Understanding how brain activity encodes information and controls behavior is a long-standing question in *** complex problem requires converging efforts from neuroscience and engineering,including technological solutions to perform high-precision and large-scale recordings of neuronal activity in vivo as well as unbiased methods to reliably measure and quantify *** to advances in genetics,molecular biology,engineering,and neuroscience,in recent decades,a variety of optical imaging and electrophysiological approaches for recording neuronal activity in awake animals have been developed and widely applied in the ***,sophisticated computer vision and machine learning algorithms have been developed to analyze animal *** this review,we provide an overview of the current state of technology for neuronal recordings with a focus on optical and electrophysiological methods in *** addition,we discuss areas that future technological development will need to cover in order to further our understanding of the neural activity underlying behavior.

关键词： recording lying technological

Brain iron overload following intracranial haemorrhage

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Stroke & Vascular Neurology 2016年第4期1卷 172-184页

作者： Thomas Garton richard F Keep Ya Hua Guohua Xi Department of Neurosurgery University of MichiganAnn ArborMichiganUSA

Intracranial haemorrhages,including intracerebral haemorrhage(ICH),intraventricular haemorrhage(IVH)and subarachnoid haemorrhage(SAH),are leading causes of morbidity and mortality *** addition,haemorrhage contributes to tissue damage in traumatic brain injury(TBI).To date,efforts to treat the long-term consequences of cerebral haemorrhage have been *** rates and mortality have not showed significant improvement in recent *** terms of secondary damage following haemorrhage,it is becoming increasingly apparent that blood components are of integral importance,with haemoglobin-derived iron playing a major ***,the damage caused by iron is complex and varied,and therefore,increased investigation into the mechanisms by which iron causes brain injury is *** ICH,IVH,SAH and TBI are related,this review will discuss the role of iron in each,so that similarities in injury pathologies can be more easily *** summarises important components of normal brain iron homeostasis and analyses the existing evidence on iron-related brain injury *** further discusses treatment options of particular promise.

关键词： mortality damage homeostasis

Multi-Agent System for Electric Vehicle Charging Scheduling in Parking Lots

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Complex System Modeling and Simulation 2023年第2期3卷 129-142页

作者： Mao Tan Zhonglin Zhang Yuling Ren Irampaye richard Yuzhou Zhang School of Automation and Electronic Information Xiangtan UniversityXiangtan 411105China School of Computer Science&School of Cyberspace Science Xiangtan UniversityXiangtan 411105China Hunan National Center for Applied Mathematics Xiangtan UniversityXiangtan 411105China Hunan Hi-Tech New Energy Co.Ltd. Changsha 410006China.

As the number of electric vehicles(evs)increases,massive numbers of evs have started to gather in commercial parking lots to charge and discharge,which may significantly impact the operation of the *** may also be a deviation in the departure time of charged and discharged evs in commercial parking *** deviation can lead to insufficient battery energy when the evs leave the parking *** study uses the simulation software AnyLogic to build a commercial parking lot multi-agent simulation model,and the agent-based model can fully reflect the autonomy of individual *** on this simulation model,we propose an ev scheduling *** algorithm contains two main *** first is the power distribution center agent(PDCA),which is used to coordinate the energy output of photovoltaic(PV),energy storage system(ESS),and distribution station(DS)to solve the problem of grid *** second is the scheduling center agent(SCA),which is used to solve the insufficient battery energy problem due to evs’random *** SCA includes two *** the first stage,a priority scheduling algorithm is proposed to emphasize the fairness of ev *** the second stage,a genetic algorithm is used to accurately determine the time interval between charging and discharging to ensure the maximum benefit of ev ***,simulation experiments are conducted in AnyLogic,and the results demonstrate the superiority of the algorithm over the classical algorithm.

关键词： electric vehicle charging scheduling multi-agent system simultation optimization

Through-needle all-optical ultrasound imaging in vivo: a preclinical swine study

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Light(Science & Applications) 2017年第1期6卷 70-76页

作者： Malcolm C Finlay Charles A Mosse richard J Colchester Sacha Noimark Edward Z Zhang Sebastien Ourselin Paul C Beard richard J Schilling Ivan P Parkin Ioannis Papakonstantinou Adrien E Desjardins William Harvey Cardiovascular Research Institute Queen Mary University of London and Barts Heart CentreLondon EC1A 7BEUK Wellcome/EPSRC Centre for Interventional and Surgical Sciences University College LondonCharles Bell House67-73 Riding House StreetLondon W1W 7EJUK UCL Centre for Materials Research Department of ChemistryUniversity College LondonLondon WC1H 0AJUK Department of Electronic and Electrical Engineering University College LondonLondon WC1E 7JEUK

High-frequency ultrasound imaging can provide exquisite visualizations of tissue to guide minimally invasive ***,we demonstrate that an all-optical ultrasound transducer,through which light guided by optical fibers is used to generate and receive ultrasound,is suitable for real-time invasive medical imaging in ***-bandwidth ultrasound generation was achieved through the photoacoustic excitation of a multiwalled carbon nanotube-polydimethylsiloxane composite coating on the distal end of a 300-μm multi-mode optical fiber by a pulsed *** interrogation of a high-finesse Fabry–Pérot cavity on a single-mode optical fiber by a wavelength-tunable continuous-wave laser was applied for ultrasound *** transducer was integrated within a custom inner transseptal needle(diameter 1.08 mm;length 78 cm)that included a metallic septum to acoustically isolate the two optical *** use of this needle within the beating heart of a pig provided unprecedented realtime views(50 Hz scan rate)of cardiac tissue(depth:2.5 cm;axial resolution:64μm)and revealed the critical anatomical structures required to safely perform a transseptal crossing:the right and left atrial walls,the right atrial appendage,and the limbus fossae *** new paradigm will allow ultrasound imaging to be integrated into a broad range of minimally invasive devices in different clinical contexts.

关键词： cardiac medical devices optoacoustic photoacoustic ultrasound