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Women in visual neural regeneration research

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Neural Regeneration Research 2025年第2期20卷 489-490页

作者： Tonia S.Rex david J.Calkins Vanderbilt Eye Institute Vanderbilt University Medical CenterNashvilleTNUSA

The year 2024 marks the 60^(th)anniversary of Title IX and 25 years since the New York Times revealed bias against female faculty members at the Massachusetts Institute of *** take an opportunity here to examine the state of gender bias in a relatively new yet already prominent field,neural regeneration in the visual system,for which there is a well-defined context useful for this *** National Eye Institute(NEI)provided the first round of research funding for its Audacious Goals Initiative(AGI)on visual neural regeneration in 2013 and the last round in ***,we focus on this *** sources included pubMed,the National Science Foundation(NSF),the NEI,the Blue Ridge Institute for Medical Research and data from the major professional organization for eye and vision research,the Association for Research in Vision and Ophthalmology(ARVO).

关键词： neural visual Times

potential physiological and pathological roles for axonal ryanodine receptors

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Neural Regeneration Research 2023年第4期18卷 756-759页

作者： david p.Stirling Kentucky Spinal Cord Injury Research Center and Departments of Neurological Surgery Anatomical Sciences and NeurobiologyMicrobiology and ImmunologyUniversity of LouisvilleSchool of MedicineLouisvilleKYUSA

Clinical disability following trauma or disease to the spinal cord often involves the loss of vital white matter elements including axons and *** excessive Cais an established driver of axonal degeneration,therapeutically targeting externally sourced Cato date has had limited success in both basic and clinical *** factors that may underlie this limited success include the complexity of the many potential sources of Caentry and the discovery that axons also contain substantial amounts of stored Cathat if inappropriately released could contribute to axonal *** Castorage is largely accomplished by the axoplasmic reticulum that is part of a continuous network of the endoplasmic reticulum that provides a major sink and source of intracellular Cafrom the tips of dendrites to axonal ***“neuron-within-a-neuron”is positioned to rapidly respond to diverse external and internal stimuli by amplifying cytosolic Calevels and generating short and long distance regenerative Cawaves through Cainduced *** review provides a glimpse into the molecular machinery that has been implicated in regulating ryanodine receptor mediated Carelease in axons and how dysregulation and/or overstimulation of these internodal axonal signaling nanocomplexes may directly contribute to Ca-dependent axonal *** ryanodine receptors expressed in dendrites,soma,and axonal terminals have been implicated in synaptic transmission and synaptic plasticity,but a physiological role for internodal localized ryanodine receptors remains largely *** physiological roles for internodal ryanodine receptors and such an elaborate internodal binary membrane signaling network in axons will also be discussed.

关键词： axomyelinic synapse axon axoplasmic reticulum calcium ryanodine receptor secondary axonal degeneration spinal cord injury voltage-gated calcium channel white matter injury

Gradient microstructure and enhanced mechanical performance of magnesium alloy by severe impact loading

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Journal of Materials Science & Technology 2020年第1期36卷 45-49页

作者： Maryam Jamalian david p.Field School of Mechanical and Materials Engineering.Washington State University PullmanUSA

Subjecting a workpiece to a surface treatment with severe impact loading is a novel severe plastic deformation procedure to fabricate gradient microstructures through the thickness and longitudinal *** performance is a function of twin density and the newly-formed grain size gradients.{1012}tensile twins created from processing without excessive grain refinement lead to strength enhancement with retained *** of residual strain by a single impact results in a significant reduction in time and cost of the *** paper investigates the effect of applying severe impact loading on mechanical and microstructural properties of magnesium for various impact velocities.

关键词： Surface modification Twinning Magnesium alloys Mechanical properties Severe impact loading(SIL)

Contemporary coronary artery bypass grafting

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Frontiers of Medicine 2014年第4期8卷 395-398页

作者： david p. Taggart Nuffield Department of Surgery University of Oxford John Radcliffe Hospital Oxford OX3 9DU UK

Current evidence clearly demonstrates that coronary artery bypass grafting （CABG） remains the ＂gold standard＂ treatment for most patients with multivessel and left main stem disease. This article summarizes the relevant evidence basis demonstrating that CABG, in comparison to stenting, reduces mortality and subsequent myocardial infarction and the need for repeat revascularization. The article also describes the evidence basis to support the use of more arterial grafts during CABG and the current role of off-pump CABG.

关键词： coronary artery bypass grafting (CABG) coronary artery disease left main arterial grafts internal mammary artery off-pump CABG

Direct-to-indirect mapping for optimal low-thrust trajectories

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Astrodynamics 2024年第1期8卷 27-46页

作者： david Ottesen Ryan p.Russell Department of Aerospace Engineering and Engineering Mechanics The University of Texas at AustinAustinTexas78712USA

Optimal,many-revolution spacecraft trajectories are challenging to solve.A connection is made for a class of models between optimal direct and indirect *** transfers that minimize thrust-acceleration-squared,primer vector theory maps direct,many-impulsive-maneuver trajectories to the indirect,continuous-thrust-acceleration *** mapping algorithm is independent of how the direct solution is obtained and requires only a solver for a boundary value problem and its partial derivatives.A Lambert solver is used for the two-body problem in this *** mapping is simple because the impulsive maneuvers and co-states share the same linear space around an optimal *** numerical results,the direct coast-impulse solutions are demonstrated to converge to the indirect continuous solutions as the number of impulses and segments *** two-body design space is explored with a set of three many-revolution,many-segment examples changing semimajor axis,eccentricity,and *** first two examples involve a small change to either semimajor axis or eccentricity,and the third example is a transfer to geosynchronous *** a single processor,the optimization runtime is seconds to minutes for revolution counts of 10 to 100,and on the order of one hour for examples with up to 500 *** of these thrust-acceleration-squared solutions are good candidates to start a homotopy to a higher-fidelity minimization problem with practical constraints.

关键词： direct optimization indirect optimization impulsive maneuvers Lambert's problem two-body dynamics primer vectortheory

A Quadratic Lower Bound for Three-Query Linear Locally Decodable Codes over Any Field

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Journal of Computer Science & Technology 2012年第4期27卷 678-686页

作者： david p.Woodruff IBM Almaden Research Center Yorktown HeightsN.Y.10598U.S.A.

A linear （q,δ,ε, m（n））-locally decodable code （LDC） C ： F^n → F^m（n） is a linear transformation from the vector 1 space F^m（n） to the space F^m（n） for which each message symbol xi can be recovered with probability at least 1/｜F｜＋ε from C（x） by a randomized algorithm that queries only q positions of C（x）, even if up to δm（n） positions of C（x） are corrupted. In a recent work of Dvir, the author shows that lower bounds for linear LDCs can imply lower bounds for arithmetic circuits. He suggests that proving lower bounds for LDCs over the complex or real field is a good starting point for approaching one of his conjectures. Our main result is an re（n） =Ω（n^2） lower bound for linear 3-query LDCs over any, possibly infinite, field. The constant in the Ω（·） depends only on ε and δ. This is the first lower bound better than the trivial re（n） = Ω（n） for arbitrary fields and more than two queries.

关键词： error-correcting code complexity theory lower bound

Understanding p53 functions through p53 antibodies

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Journal of Molecular Cell Biology 2019年第4期11卷 317-329页

作者： Kanaga Sabapathy david p.Lane Laboratory of Molecular Carcinogenesis Division of Cellular & Molecular Research Humphrey Oei Institute of Cancer Research National Cancer Centre Singapore Singapore 169610 Singapore Cancer and Stem Cell Biology program Duke-NUS Medical School Singapore 169857 Singapore Department of Biochemistry National University of Singapore (NUS) Singapore 117597 Singapore Institute of Molecular and Cellular Biology Singapore 138673 Singapore p53 Laboratory Singapore 138648

Tp53 is the most frequently mutated gene across all cancer types. Our understanding of its functions has evolved since its discovery four decades ago. Initially thought to be an oncogene, it was later realized to be a critical tumour suppressor. A significant amount of our knowledge about p53 functions have come from the use of antibodies against its various forms. The early anti-p53 antibodies contributed to the recognition of p53 accumulation as a common feature of cancer cells and to our understanding of p53 DNA-binding and transcription activities. They led to the concept that conformational changes can facilitate p53’s activity as a growth inhibitory protein. The ensuing p53 conformational-specific antibodies further underlined p53’s conformational flexibility, collectively forming the basis for current efforts to generate therapeutic molecules capable of altering the conformation of mutant p53. A subsequent barrage of antibodies against post-translational modifications on p53 has clarified p53’s roles further, especially with respect to the mechanistic details and context-dependence of its activity. More recently, the generation of p53 mutation-specific antibodies have highlighted the possibility to go beyond the general framework of our comprehension of mutant p53-and promises to provide insights into the specific properties of individual p53 mutants. This review summarizes our current knowledge of p53 functions derived through the major classes of anti-p53 antibodies, which could be a paradigm for understanding other molecular events in health and disease.

关键词： antibodies conformation mutant p53 post-translational modifications

MICROSCOpIC HETEROGENEITY IN VISCOELASTIC pROpERTIES OF MOLECULAR ASSEMBLED SYSTEMS

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Chinese Journal of polymer Science 2013年第1期31卷 1-1,2-11页

作者： Atsuomi Shundo david p. penaloza Keiji Tanaka Department of Applied Chemistry Kyushu University International Institute for Carbon-Neutral Energy Research (WpI-I2CNER) Kyushu University

An important step in understanding molecular assembled systems is to examine the structure and physical properties at various length scales and clarify the correlation between them. However, while the structures of these systems have been extensively studied from nanoscopic to macroscopic scales, their viscoelastic properties have been often limited to bulk rheological measurements. By using optical tweezers and particle tracking, we here show the local viscoelastic properties and their spatial distributions for the following systems： worm-like micelle solution, supramolecular hydrogel and lyotropic liquid crystal, which are formed by self-assembly of amphiphilic molecules in water. We found that all systems studied possessed a spatial heterogeneity in their viscoelastic properties and this was originated from the heterogeneous structures. It is interesting to note that there is the heterogeneity with the characteristic length scale of sub-micrometer or micrometer scale, thereby structures, although the systems are formed by molecules with nanometer size. The findings of these studies should lead to a better understanding of the dynamics of such systems.

关键词： Optical tweezers Soft materials Heterogeneity Hierarchical structure Rheological properties.

The great catastrophe: causes of the permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： paul B.Wignall david p.G.Bond School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(pid warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern Boreal latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter