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Feasibility study of phase-sensitive imaging based on multiple reference optical coherence tomography

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Chinese Optics Letters 2017年第9期15卷 25-30页

作者： Roshan Dsouza Hrebesh Subhash Kai Neuhaus Paul m.mcNamara josh Hogan Carol wilson martin j.Leahy Tissue Optics and microcirculation Imaging Group School of PhysicsNational University of IrelandGalway H91 CF50Ireland Compact Imaging Ireland Ltd. Galway H91 CF50Ireland Colgate-Palmolive Global Technology Centre Piscataway NJ 08855USA Compact Imaging Inc.Mountain View 94043USA Royal College of Surgeons(RCSI) DublinIreland

multiple reference optical coherence tomography（mR-OCT） is a recently developed, low-cost and compact time-domain OCT solution for primary care and consumer level applications. A combination of a voice coil actuator and a partial mirror（Pm） extends the scan range for imaging depths of approximately 1 mm in biological samples. Our previous research on mR-OCT is based only on intensity information obtained from the depth-resolved interference signal. In this Letter, we extract the phase information from the mR-OCT signal and, hence, provide an additional contrast modality. The phase sensitivity of the system is measured to be approximately 0.2 and 1.5 rad for the first and twelfth orders of reflection when using a mirror as the *** Letter describes first results of phase-sensitive data measured on a phantom obtained with mR-OCT. Data from a chick embryo chorioallantoic membrane（CAm） is used to demonstrate the feasibility of mR-OCT for in vivo phase-sensitive imaging.

关键词： Feasibility study of phase-sensitive imaging based on multiple reference optical coherence tomography VCm Figure CAm

Target blood pressure in diabetes patients with hypertension——What is the accumulated evidence in 2011?

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journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第8期12卷 611-623页

作者： peter m.NILSSON Department of Clinical Sciences Lund UniversityUniversity Hospital

There is overwhelming evidence that hypertension is an important risk factor for both macrovascular and microvascular complications in patients with diabetes,but the problem remains to identify appropriate goals for preventive therapies.A number of guidelines (the European Society of Cardiology (ESC)/European Association for the Study of Diabetes (EASD) 2007,the joint National Committee (jNC)-Ⅶ 2003,the American Diabetes Association (ADA) 2011) have for example advocated a blood pressure goal of less than 130/80 mmHg,but this suggestion has been challenged by findings in recent trials and meta-analyses (2011).The European Society of Hypertension (ESH) therefore recommends a systolic blood pressure goal of "well below" 140 *** on evidence from both randomized controlled trials (hypertension optimal treatment (HOT),action in diabetes and vascular disease:preterax and diamicron mR controlled evaluation (ADVANCE),action to control cardiovascular risk in diabetes (ACCORD)) and observational studies (ongoing telmisartan alone and in combination with ramipril global endpoint trial (ONTARGET),international verapamil-trandolapril study (INVEST),treat to new targets (TNT),and the National Diabetes Register (NDR)),it has been shown that the benefit for stroke reduction remains even at lower achieved blood pressure levels,but the risk of coronary events may be uninfluenced or even increased at lower systolic blood pressure *** a recent meta-analysis,it was therefore concluded that the new recommended goal should be 130-135 mmHg systolic blood pressure for most patients with type 2 *** risk factors should also be controlled with a more ambitious strategy applied in the younger patients with shorter diabetes duration,but a more cautious approach in the elderly and frail patients with a number of vascular or non-vascular *** patients from East Asia,such as China,the stroke risk is relatively higher than the risk of coronary *** must al

关键词： Blood pressure Cardiovascular Diabetes Goal Hypertension Treatment

Quantum corrections for Boltzmann equation

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Science China(Physics,mechanics & Astronomy) 2008年第9期51卷 1229-1239页

作者： m. Levy peter Department of Physics New York University

We present the lowest order quantum correction to the semiclassical Boltzmann distribution function,and the equation satisfied by this correction is given. Our equation for the quantum correction is obtained from the conventional quantum Boltzmann equation by explicitly expressing the Planck constant in the gradient approximation,and the quantum Wigner distribution function is expanded in pow-ers of Planck constant,too. The negative quantum correlation in the Wigner dis-tribution function which is just the quantum correction terms is naturally singled out,thus obviating the need for the Husimi’s coarse grain averaging that is usually done to remove the negative quantum part of the Wigner distribution function. We also discuss the classical limit of quantum thermodynamic entropy in the above framework.

关键词： quantum Boltzmann equation Wigner distribution function quantum correction

Testing flexible polymer solar cells in near-space

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National Science Review 2023年第5期10卷 105-106页

作者： peter müller-Buschbaum Department of Physics TUM School of Natural Sciencesand Heinz Maier-Leibnitz-Zentrum(MLZ)Technical University of Munich

Since the big success of the Vanguard1 mission,being the first solar-powered satellite,the use of solar cells in space developed very ***,conventional solar cell technologies for space are based on silicon and GaAs **...

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Fluid and Osmotic Pressure Balance and Volume Stabilization in Cells Dedicated to Professor Karl Stark Pister for his 95th birthday

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Computer modeling in Engineering & Sciences 2021年第12期129卷 1329-1350页

作者： peter m.Pinsky Department of mechanical Engineering Stanford UniversityStanford94305CAUSA

A fundamental problem for cells with their fragile membranes is the control of their *** primordial solution to this problem is the active transport of ions across the cell membrane to modulate the intracellular osmotic *** this work,a theoretical model of the cellular pump-leak mechanism is proposed within the general framework of linear nonequilibrium *** model is expressed with phenomenological equations that describe passive and active ionic transport across cell membranes,supplemented by an equation for the membrane potential that accounts for the electrogenicity of the ionic *** active ionic transport,the model predicts that the intracellular fluid pressure will be balanced by the osmotic pressure and a new pressure component that arises from the active ionic fluxes.A model for the pump-leak mechanism in an idealized human cell is introduced to demonstrate the applicability of the proposed theory.

关键词： Pump-leak mechanism cell volume regulation active ion transport ion pump membrane transport cell mechanics modified Kedem-Katchalsky equations nonequilibrium thermodynamics phenomenological equations

mass Transport in Nanowire Synthesis:An Overview of Scalable Nanomanufacturing

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journal of materials Science & Technology 2015年第6期31卷 523-532页

作者： matthew j.Crane peter j.Pauzauskie Department of Chemical Engineering University of WashingtonSeattleWA 98195-1750.USA Department of materials Science & Engineering Seattle.WA 98195-2120USA Fundamental Computational Science Directorate Pacific Northwest National LaboratoryRichland.WAUSA

The ability to rationally engineer the growth and nanomanufacturing of one-dimensional nanowires in high volumes has the potential to enable applications of nanoscale materials in a diverse range of fields including energy conversion and storage,catalysis,sensing,medicine,and information *** review provides a roadmap for the development of large-scale nanowire *** myriad techniques exist for bench-scale nanowire synthesis,these growth strategies typically fall within two major categories:1) anisotropically-catalyzed growth and 2) confined,template-based ***,comparisons between growth methods with different mass transport pathways have led to confusion in interpreting observations,in particular Gibbs-Thomson *** review mass transport in nanowire synthesis techniques to unify growth models and to allow for direct comparison of observations across different *** addition,we discuss the applicability of nanoscale,Gibbs-Thomson effects on mass transport and provide guidelines for the development of new growth *** explore the scalability of these complex processes with dimensionless numbers and consider the effects of pressure,temperature,and precursor material on nanowire growth.

关键词： Nanowire mass transport modeling Scalable growth

Effect of oxygen and nitrogen functionalization on the physical and electronic structure of graphene

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Nano Research 2015年第8期8卷 2620-2635页

作者： Alexander j. marsden peter Brommer james j. mudd m. Adam Dyson Robert Cook maria Asensio jose Avila Ana Levy jeremy Sloan David Quigley Gavin R. Bell Neil R. wilson Department of Physics University of Warwick Coventry UK Centre for Scientific Computing University of Warwick Coventry UK Synchrotron SOLEIL L'Orme des Merisiers Saint Aubin-BP 48 91192 Gifsur Yvette Cedex France

Covalent functionalization of graphene offers opportunities for tailoring its properties and is an unavoidable consequence of some graphene synthesis techniques. However, the changes induced by the functionalization are not well understood. By using atomic sources to control the extent of the oxygen and nitrogen functionalization, we studied the evolution in the structure and properties at the atomic scale. Atomic oxygen reversibly introduces epoxide groups whilst, under similar conditions, atomic nitrogen irreversibly creates diverse functionalities including substitutional, pyridinic, and pyrrolic nitrogen. Atomic oxygen leaves the Fermi energy at the Dirac point （i.e., undoped）, whilst atomic nitrogen results in a net n-doping; however, the experimental results are consistent with the dominant electronic effect for both being a transition from delocalized to localized states, and hence the loss of the signature electronic structure of graphene.

关键词： graphene functionalization chemical vapor deposition density functional theory

Characterization of colonic dendritic cells in normal and colitic mice

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World journal of Gastroenterology 2005年第40期11卷 6338-6347页

作者： Sheena m Cruickshank Nicholas R English peter j Felsburg Simon R Carding Institute of molecular and Cellular Biology Antigen Presentation Research Group Department of Clinical Science

AIm： Recent studies demonstrating the direct involvement of dendritic cells （DC） in the activation of pathogenic T cells in animal models of inflammatory bowel disease identify DC as important antigen presenting cells in the colon. However, very little is known about the properties of colonic DC. mETHODS： Using immunohistochemistry, electron microscopy and flow cytometry we have characterized and compared colonic DC in the colon of healthy animals and interleukin-2-deficient （IL2-/-） mice that develop colitis. RESULTS： In the healthy colon, DC resided within the lamina propria and in close association with the basement membrane of colonic villi. Type i myeloid （CD11c^＋, CD11b^＋, B220, CD8） DC made up the largest （40-45%） population and all DC expressed low levels of CD80, CD86, and CD40, and had high endooltic activity consistent with an immature phenotype. In colitic IL2-/- mice, colonic DC numbers increased four- to five-fold and were localized within the epithelial layer and within aggregates of T and B cells. They were also many more DC in mesenteric lymph nodes （mLN）. The majority （〉85%） of DC in the colon and mLN of IL2./ mice were type 1 myeloid, and expressed high levels of mHC class II, CD80, CD86, CD40, DEC 205, and CCR5 molecules and were of low endocytic activity consistent with mature DC. CONCLUSION： These findings demonstrate striking changes in the number, distribution and phenotype of DC in the inflamed colon. Their intimate association with lymphocytes in the colon and draining lymph nodes suggest that they may contribute directly to the ongoing inflammation in the colon.

关键词： Colonic dendritic cells Interleukin 2 Colitis

management of ejaculatory disorders in infertile men

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Asian journal of Andrology 2012年第4期14卷 525-529页

作者： Yagil Barazani peter j Stahl Harris m Nagler Doron S Stember Beth Israel medical Center and the Albert Einstein College of medicine of Yeshiva University New YorkNew York 10003USA Department of Urology Columbia University Medical CenterNew YorkNY 10003USA

Ejaculatory dysfunction is a highly prevalent clinical condition that may be classified along a continuum that ranges from premature ejaculation （PE）, through retarded or delayed ejaculation （DE）, to complete anejaculation （AE）. Retrograde ejaculation （RE） represents a distinct entity in which ejaculate is expelled either partially or completely into the bladder. While DE and PE are significant sources of sexual dissatisfaction among men and their partners, patients with these disorders retain normal fertility in most cases. Conversely, men with AE and RE are unable to deliver sperm into the female genital tract and are therefore rendered subfertile. Therefore, in reviewing ejaculatory disorders as they relate to fertility, this paper will primarily focus on the diagnosis and management of AE and RE. Physiology, diagnostic strategies, pharmacological treatments, and procedural interventions relevant to AE and RE are discussed.

关键词： anejaculation delayed ejaculation ejaculatory dysfunction electroejaculation penile vibratory stimulation prematureejaculation retrograde ejaculation