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Evolutionary ecology of chemosensation and its role in sensory drive

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Current Zoology 2018年第4期64卷 525-533页

作者： Laurel R. YOHE Philipp BRAND department of Ecology and Evolution Stony Brook University Stony Brook NY 11790 USA department of Geology & Geophysics Yale University New Haven CT 06511 USA department of Evolution and Ecology Center for Population Biology University of California Davis CA 95616 USA

All behaviors of an organism are rooted in sensory processing of signals from its environment, and nat ural selection shapes sensory adaptations to ensure successful detection of cues that maximize fitness. Sensory drive, or divergent selection for efficient signal transmission among heterogeneous environ ments, has been a useful hypothesis for describing sensory adaptations, but its current scope has pri marily focused on visual and acoustic sensory modalities. Chemosensation, the most widespread sensory modality in animals that includes the senses of smell and taste, is characterized by rapid evolu tion and has been linked to sensory adaptations to new environments in numerous lineages. Yet, olfac tion and gustation have been largely underappreciated in light of the sensory drive hypothesis. Here, we examine why chemosensory systems have been overlooked and discuss the potential of chemo sensation to shed new insight on the sensory drive hypothesis and vice versa. We provide suggestions for developing a framework to better incorporate studies of chemosensory adaptation that have the po tential to shape a more complete, coherent, and holistic interpretation of the sensory drive.

关键词： chemical signaling chemoreceptor chemosensation sensory drive olfaction

Breast-to-brain metastasis: a focus on the premetastatic niche

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Journal of Cancer Metastasis and Treatment 2021年第1期7卷 551-568页

作者： Kathryn Malone Stella E.Tsirka department of Pharmacological Sciences Renaissance School of Medicine at Stony Brook UniversityStony BrookNY 11794-8651USA.

Metastatic disease is the cause for 90%of breast cancer *** those 10%-20%of patients whose breast cancer metastasizes to the central nervous system,the one-year survival rate is just 20%.Both histology and molecular subtype have a correlation with the site of tumor metastasis,indicating an inherent preferential aspect to metastatic colony *** molecular differences between breast cancers may determine the site of metastasis through priming of the premetastatic niche in that site:cell surface molecules,exosomes released from the primary tumor,and soluble factors secreted from both the primary tumor and resident cells within the premetastatic niche all contribute to altering the premetastatic niche to be more favorable for the circulating tumor cells,allowing for cell invasion and ***,we review breast to brain metastasis with a focus on the premetastatic *** discuss the secreted factors and exosomes that prime the premetastatic niche within the brain by instigating crosstalk between the resident cells of the brain *** report on the individual roles that microglia,astrocytes,pericytes,neurons,and endothelial cells may have in the formation and maintenance of the premetastatic niche.

关键词： Niche metastasis breast cancer brain

Ambient synthesis, characterization, and electrochemical activity of LiFePO4 nanomaterials derived from iron phosphate intermediates

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Nano Research 2015年第8期8卷 2573-2594页

作者： Jonathan M. Patete Megan E. Scofield Vyacheslav Volkov Christopher Koenigsmann Yiman Zhang Amy C. Marschilok Xiaoya Wang Jianming Bai Jinkyu Han Lei Wang Feng Wang Yimei Zhu Jason A. Graetz Stanislaus S. Wong department of chemistry State University of New York at Stony Brook Stony Brook NY 77794-3400 USA Condensed Matter Physics and Materials Sciences department Building 480 Brookhaven National Laboratory Upton NY 11973 USA department of Materials Science and Engineering State University of New York at Stony Brook Stony Brook NY 11794-2275 USA Sustainable Energy Technologies department Building 815 Brookhaven National Laboratory Upton NY 11973 USA National Synchrotron Light Source II Building 741 Brookhaven National Laboratory Upton NY 11973 USA

LiFePO4 materials have become increasingly popular as a cathode material due to the many benefits they possess including thermal stability, durability, low cost, and long life span. Nevertheless, to broaden the general appeal of this material for practical electrochemical applications, it would be useful to develop a relatively mild, reasonably simple synthesis method of this cathode material. Herein, we describe a generalizable, 2-step methodology of sustainably synthesizing LiFePO4 by incorporating a template-based, ambient, surfactantless, seedless, U-tube protocol in order to generate size and morphologically tailored, crystalline, phase-pure nanowires. The purity, composition, crystallinity, and intrinsic quality of these wires were systematically assessed using transmission electron microscopy （TEM）, high-resolution TEM （HRTEM）, scanning electron microscopy （SEM）, X-ray diffraction （XRD）, selected area electron diffraction （SAED）, energy dispersive analysis of X-rays （EDAX）, and high-resolution synchrotron XRD. From these techniques, we were able to determine that there is an absence of any obvious defects present in our wires, supporting the viability of our synthetic approach. Electrochemical analysis was also employed to assess their electrochemical activity. Although our nanowires do not contain any noticeable impurities, we attribute their less than optimal electrochemical rigor to differences in the chemical bonding between our LiFePO4 nanowires and their bulk-like counterparts. Specifically, we demonstrate for the first time experimentally that the Fe-O3 chemical bond plays an important role in determining the overall conductivity of the material, an assertion which is further supported by recent ＂first-principles＂ calculations. Nonetheless, our ambient, solution-based synthesis technique is capable of generating highly crystalline and phase-pure energy-storage-relevant nanowires that can be tailored so as to fabricate different sized materials of repro

关键词： ambient synthesis template synthesis cathode material lithium iron phosphate nanostructures

Centrosome positioning and primary cilia assembly orchestrate neuronal development

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Frontiers of physics 2012年第5期7卷 412-427页

作者： Sneha RAO Shaoyu GE Maya SHELLY Program in Neuroscience State University of New York at Stony Brook Stony Brook NY 11794-5230 USA department of Neurobiology and Behavior State University of New York at Stony Brook Stony Brook NY 11794-5230 USA

Establishment of axon and dendrite polarity, migration to a desired location in the developing brain, and establishment of proper synaptic connections are essential processes during neuronal development. The cellular and molecular mechanisms that govern these processes are under intensive investigation. The function of the centrosome in neuronal development has been examined and discussed in few recent studies that underscore the fundamental role of the centrosome in brain development. Clusters of emerging studies have shown that centrosome positioning tightly regulates neuronal development, leading to the segregation of cell factors, directed neurite differentiation, neuronal migration, and synaptic integration. Furthermore, cilia, that arise from the axoneme, a modified centriole, are emerging as new regulatory modules in neuronal development in conjunction with the centrosome. In this review, we focus on summarizing and discussing recent studies on centrosome positioning during neuronal development and also highlight recent findings on the role of cilia in brain development. We further discuss shared molecular signaling pathways that might regulate both centrosome and cilia associated signaling in neuronal development. Furthermore, molecular determinants such as DISC1 and LKB1 have been recently demonstrated to be crucial regulators of various aspects of neuronal development. Strikingly, these determinants might exert their function, at least in part, via the regulation of centrosome and cilia associated signaling and serve as a link between these two signaling centers. We thus include an overview of these molecular determinants.

关键词： centrosome positioning neuronal polarization/migration primary cilia

Fourier Descriptors with Different Shape Signatures:a Comparative Study for Shape Based Retrieval of Kinematic Constraints

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Chinese Journal of Mechanical Engineering 2011年第5期24卷 723-730页

作者： WU Jun GE Qiaode Jeffrey GAO Feng SU Haijun Computational Design Kinematics Lab Department of Mechanical Engineering Stony Brook University Stony Brook NY 11794-2300 USA State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China department of Mechanical Engineering University of Maryland Baltimore Maryland 21250 USA

Fourier Descriptors（FD） has been widely used in image analysis and computer vision for shape recognition as they can be made independent of translation,rotation,as well as *** have also been used for developing methods for the analysis and synthesis of four-bar linkages for path *** paper focuses on a comparative study of Fourier descriptors derived from various shape signatures of planar closed *** includes representations based on Cartesian coordinates,centroid distance,cumulative angle,and *** comparison is conducted not only using commonly used criteria for shape representation and identification but also in the context of shape based retrieval of kinematic constraints for task centered mechanism *** are provided to seek to extract geometric constraints such as circle,circular arc,ellipse and line-segment from a given motion.

关键词： Fourier descriptors kinematic constraints shape recognition and retrieval

Missing data and the accuracy of Bayesian phylogenetics

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植物分类学报 2008年第3期46卷 307-314页

作者： John J. WIENS Daniel S. MOEN department of Ecology and Evolution Stony Brook University Stony Brook NY 11794-5245 USA

The effect of missing data on phylogenetic methods is a potentially important issue in our attempts to reconstruct the Tree of Life. If missing data are truly problematic, then it may be unwise to include species in an analysis that lack data for some characters (incomplete taxa) or to include characters that lack data for some species. Given the difficulty of obtaining data from all characters for all taxa (e.g., fossils), missing data might seriously impede efforts to reconstruct a comprehensive phylogeny that includes all species. Fortunately, recent simulations and empirical analyses suggest that missing data cells are not themselves problematic, and that in-complete taxa can be accurately placed as long as the overall number of characters in the analysis is large. How-ever, these studies have so far only been conducted on parsimony, likelihood, and neighbor-joining methods. Although Bayesian phylogenetic methods have become widely used in recent years, the effects of missing data on Bayesian analysis have not been adequately studied. Here, we conduct simulations to test whether Bayesian analyses can accurately place incomplete taxa despite extensive missing data. In agreement with previous studies of other methods, we find that Bayesian analyses can accurately reconstruct the position of highly incomplete taxa (i.e., 95% missing data), as long as the overall number of characters in the analysis is large. These results suggest that highly incomplete taxa can be safely included in many Bayesian phylogenetic analyses.

关键词：贝叶斯定理系统发生学数据缺失准确度

Excited-State Palladium-Catalyzed α-Selective C1-Ketonylation

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CCS chemistry 2023年第1期5卷 106-116页

作者： Gaoyuan Zhao Upasana Mukherjee Lin Zhou Jaclyn NMauro Yue Wu Peng Liu Ming-Yu Ngai department of chemistry Institute of Chemical Biology and Drug DiscoveryState University of New York at Stony BrookStony BrookNew York 11794 department of chemistry University of PittsburghPittsburghPennsylvania 15260 department of Chemical and Petroleum Engineering University of PittsburghPittsburghPennsylvania 15260

C-Glycosides are important carbohydrate mimetics found in natural products,bioactive compounds,and marketed ***,stereoselective preparation of this class of glycomimetics remains a significant challenge in organic ***,we report an excited-state palladium-catalyzedα-selective C-ketonylation synthetic strategy using readily available 1-bromosugars to access a range of *** reaction featured excellentα-selectivity and mild conditions that tolerated a wide range of functional groups and complex molecular *** resultingα-ketonylsugars could serve as versatile precursors for theirβ-isomers and other *** experimental and computational studies of the mechanism suggested a radical pathway involving the formation of palladoradical and glycosyl radical that undergoes polarity-mismatched coupling with silyl enol ether,affording the desiredα-*** into the reactivity and mechanism will inspire a new reaction development and provide straightforward access to bothα-andβ-C-glycosides,thereby greatly expanding the chemical and patent spaces of glycomimetics.

关键词： excited-state catalysis palladium glycosyl radical ketonylation silyl enol ethers

Hydrothermal fabrication of selectively doped organic assisted advanced ZnO nanomaterial for solar driven photocatalysis

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Journal of Environmental Sciences 2015年第8期27卷 248-255页

作者： K.Namratha K.Byrappa S.Byrappa P.Venkateswarlu D.Rajasekhar B.K.Deepthi Center for Material Science and Technology Vijnan Bhavan Manasagangotri P.B.No 21 University of Mysore department of Materials Science and Engineering Stony Brook University department of chemistry Sri Venkateswara University

Hydrothermal fabrication of selectively doped（Ag＋＋ Pd3＋） advanced ZnO nanomaterial has been carried out under mild pressure temperature conditions（autogeneous; 150°C）.Gluconic acid has been used as a surface modifier to effectively control the particle size and morphology of these ZnO nanoparticles. The experimental parameters were tuned to achieve optimum conditions for the synthesis of selectively doped ZnO nanomaterials with an experimental duration of 4 hr. These selectively doped ZnO nanoparticles were characterized using powder X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FT-IR）, UV–Vis spectroscopy and scanning electron microscopy（SEM）. The solar driven photocatalytic studies have been carried out for organic dyes, i.e., Procion MX-5B dye,Cibacron Brilliant Yellow dye, Indigo Carmine dye, separately and all three mixed, by using gluconic acid modified selectively doped advanced ZnO nanomaterial. The influence of catalyst, its concentration and initial dye concentration resulted in the photocatalytic efficiency of 89% under daylight.

关键词： Hydrothermal technique Gluconic acid surface modification Selectively doped ZnO Photocatalytic degradation

WEAKLY COMPRESSIBLE TWO-PRESSURE TWO-PHASE FLOW

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Acta Mathematica Scientia 2009年第6期29卷 1497-1540页

作者： Hyeonseong Jin James Glimm department of Mathematics Jeju National University Jeju 690-756 Republic of Korea department of Applied Mathematics and Statistics Stony Brook University Stony Brook NY 11794-3600 Computational Science Center Brookhaven National Laboratory Upton NY 11793-6000 USA

We analyze the limiting behavior of a compressible two-pressure two-phase flow model as the Mach number tends to zero. Formal asymptotic expansions are derived for the solutions of compressible two-phase equations. Expansion coefficients through sec- ond order are evaluated in closed form. Underdetermination of incompressible pressures is resolved by information supplied from the weakly compressible theory. The incompressible pressures are uniquely specified by certain details of the compressible fluids from which they are derived as a limit. This aspect of two phase flow in the incompressible limit appears to be new, and results basically from closures which satisfy single phase boundary conditions at the edges of the mixing zone.

关键词： multiphase flow asymptotic analysis turbulence perturbation