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Chemical Research in Chinese Universities 2004年第4期20卷 411-416页

作者： LAI X. MA C. K. j. robert M. C. Miller Institute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsCCLRC Daresbury Laboratory Daresbury Leeds LS2 9JT UKLeeds LS2 9JT UKLeeds LS2 9JT UKWarrington Cheshire WA4 4AD UK

A novel crystal characterization instrument has been built up in which a combination of X-ray multiple diffraction and X-ray topography is applied to enabling the cross-correlation between micro-crystallographic symmetry and its spatial dependence in relation to lattice defects. This facility is used to examine, in a self-consistent manner, growth sector-dependant changes to both the crystallographic structure and the lattice defects associated with the action of habit-modifying additives in a number of representative crystal growth systems. In addition, the new instrument can be used to probe micro-crystallographic aspects(such as distortion to crystal symmetry) and relate these in a spatially resolved manner to the crystal defect structure in crystals doped with known habit modifiers.

关键词： X-ray diffraction X-ray multiple diffraction X-ray topography Habit modification Crystal growth Growth defects

Polarization-independent multimode interference coupler with anisotropy-engineered bricked metamaterial

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Photonics Research 2022年第4期10卷 I0001-I0009页

作者： Carlos Perez-Armenta Alej.ndro Ortega-Monux j.se Manuel Luque-Gonzalez robert Halir Pedro j.Reyes-Iglesias j.ns Schmid Pavel Cheben Inigo Molina-Fernandez j.Gonzalo Wanguemert-Perez Telecommunication Research Institute(TELMA) Universidad de MalagaCEI Andalucia TECHE.T.S.I.Telecomunicacion29010 MalagaSpain Bionand Center for Nanomedicine and Biotechnology Parque Tecnologico de AndaluciaMalaga 29590Spain National Research Council Canada OttawaOntario K1A 0R6Canada

Many applications, including optical multiplexing, switching, and detection, call for low-cost and broadband photonic devices with polarization-independent operation. While the silicon-on-insulator platform is well positioned to fulfill most of these requirements, its strong birefringence hinders the development of polarizationagnostic devices. Here we leverage the recently proposed bricked metamaterial topology to design, for the first time, to our knowledge, a polarization-independent 2 × 2 multimode interference coupler using standard 220 nm silicon thickness. Our device can be fabricated with a single etch step and is optimized for the O-band,covering a wavelength range of 160 nm with excess loss, polarization-dependent loss, and imbalance below 1 dB and phase errors of less than 5°, as demonstrated with full three-dimensional finite-difference time-domain simulations.

关键词： polarization multimode multiplexing

Development of a multivariate empirical model for predicting weak rock mass modulus

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International j.urnal of Mining Science and Technology 2015年第4期25卷 545-552页

作者： Kallu Raj.R. Keffeler Evan R. Watters robert j. Agharazi Alireza Department of Mining Engineering University of Nevada RESPEC Consulting and Services University of Nevada Itasca Houston Inc.

Estimating weak rock mass modulus has historically proven difficult although this mechanical property is an important input to many types of geotechnical analyses. An empirical database of weak rock mass modulus with associated detailed geotechnical parameters was assembled from plate loading tests performed at underground mines in Nevada, the Bakhtiary Dam proj.ct, and Portugues Dam proj.ct. The database was used to assess the accuracy of published single-variate models and to develop a multivariate model for predicting in-situ weak rock mass modulus when limited geotechnical data are *** two of the published models were adequate for predicting modulus of weak rock masses over limited ranges of alteration intensities, and none of the models provided good estimates of modulus over a range of geotechnical properties. In light of this shortcoming, a multivariate model was developed from the weak rock mass modulus dataset, and the new model is exponential in form and has the following independent variables:(1) average block size or j.int spacing,(2) field estimated rock strength,(3) discontinuity roughness, and(4) discontinuity infilling hardness. The multivariate model provided better estimates of modulus for both hard-blocky rock masses and intensely-altered rock masses.

关键词：多变量预测经验模型体模量软弱岩体弹性模量岩土工程特性经验数据库多变量模型

Plant Carbonic Anhydrases： Structures, Locations, Evolution, and Physiological Roles

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Molecular Plant 2017年第1期10卷 30-46页

作者： robert j. DiMario Harmony Clayton Ananya Mukhedee Martha Ludwig j.mes V. Moroney Department of Biological Sciences Louisiana State University Baton Rouge LA 70803 USA School of Chemistry and Biochemistry University of Western Australia Perth WA 6009 Australia

Carbonic anhydrases （CAs） are zinc metalloenzymes that catalyze the interconversion of CO2 and HCO3- and are ubiquitous in nature. Higher plants contain three evolutionarily distinct CA families, αCAs, 13CAs, and γCAs, where each family is represented by multiple isoforms in all species. Alternative splicing of CA transcripts appears common; consequently, the number of functional CA isoforms in a species may exceed the number of genes. CAs are expressed in numerous plant tissues and in different cellular locations. The most prevalent CAs are those in the chloroplast, cytosol, and mitochondria. This diversity in location is paralleled in the many physiological and biochemical roles that CAs play in plants. In this review, the number and types of CAs in C3, C4, and crassulacean acid metabolism （CAM） plants are considered, and the roles of the α and yCAs are briefly discussed. The remainder of the review focuses on plant βCAs and includes the identification of homologs between species using phylogenetic approaches, a consideration of the inter- and intracellular localization of the proteins, along with the evidence for alternative splice forms. Current understanding of βCA tissue-specific expression patterns and what controls them are reviewed, and the physiological roles for which βCAs have been implicated are presented.

关键词： carbonic anhydrase regulation alternative splicing physiological role

DC/AC circuits and electronics : principles & applications /

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Taste receptors in the upper airway

丛书名： Herrick & j.cob series

2003年

作者： Herrick robert j.

来源：畅想之星图书光盘版（南... 评论

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World j.urnal of Otorhinolaryngology-Head and Neck Surgery 2018年第1期4卷 67-76页

作者： j.nna R. Freund robert j. Lee Department of Otorhinolaryngology-Head and Neck Surgery Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA Department of Physiology Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA

Taste receptors were named for their originally-identified expression on the tongue and role in the sensation of taste (gustation). They are now known to be involved in many che-mosensory processes outside the tongue. Expression of the receptors for bitter, sweet, and umami was recently identified in many organs, including the brain, airway, gastrointestinal tract, and reproductive systems. We do not yet know the full roles of these receptors in all of these tissues, nor do we know all of the endogenous ligands that activate them. However, taste receptors are emerging as potentially important therapeutic targets. Moreover, they may mediate some off target effects of drugs, as many medications in common clinical use are known to be bitter. The focus of this review is on recent basic and clinical data describing the expression of bitter (T2R) and sweet (T1R) receptors in the airway and their activation by secreted bacterial compounds. These receptors play important roles in innate immune ni-tric oxide production and antimicrobial peptide secretion, and may be useful targets for stim-ulating immune responses in the upper respiratory tract via topical therapies. Moreover, genetic variation in these receptors may play a role in the differential susceptibility of patients to certain types of respiratory infections as well as to differential outcomes in patients with chronic rhinosinusitis (CRS). CRS is a syndrome of chronic upper respiratory infection and inflammation and has a significant detrimental impact on patient quality of life. CRS treatment accounts for approximately 20% of adult antibiotic prescriptions and is thus a large driver of the public health crisis of antibiotic resistance. Taste receptors represent a novel class of ther-apeutic target to potentially stimulate endogenous immune responses and treat CRS patients without conventional antibiotics.

关键词： Chronic rhinosinusitis Gustation Nasal disease Respiratory infection Nitric oxide Antimicrobial peptide Innate immunity Cilia

Weight measurement using image-based pose analysis

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Progress in Natural Science:Materials International 2008年第12期18卷 1507-1512页

作者： robert j.Sclabassi Laboratory for Computational Neuroseience Departments of NeurosurgeryElectrical & Computer Engineeringand BioengineeringUniversity of PittsburghPittsburgh 15213USA

Image-based gait analysis as a means of biometric identification has attracted much research *** of the existing methods focus on human identification,posture analysis and movement *** have been few investigations on measuring the carried load based on the carrier’s gait characteristics by automatic image ***,this measurement is very useful in a number of applications,such as the study of the carried load on the postural development of children and *** this paper,we inves- tigate how to automatically estimate the carried weight from a sequence of *** present a method to extract human gait silhouette based on an observation that humans tend to minimize the energy during *** compute several angles of body leaning and deter- mine the relationship of the carried weight,the leaning angles and the centroid location according to a human kinetic *** weight determination method has been verified successfully by experiments.

关键词： Image-based pose analysis Energy minimization Pattern recognition Load carrying measurement

Is plate tectonics needed to evolve technological species on exoplanets?

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Geoscience Frontiers 2016年第4期7卷 573-580页

作者： robert j.Stern Geoscience Department University of Texas at Dallas

As we continue searching for exoplanets, we wonder if life and technological species capable of communicating with us exists on any of them. As geoscientists, we can also wonder how important is the presence or absence of plate tectonics for the evolution of technological species. This essay considers this question, focusing on tectonically active roclw （silicate） planets, like Earth, Venus, and Mars. The development of technological species on Earth provides key insights for understanding evolution on exoplanets, including the likely role that plate tectonics may play. An Earth-sized silicate planet is likely to experience several tectonic styles over its lifetime, as it cools and its lithosphere thickens, strengthens, and becomes denser. These include magma ocean, various styles of stagnant lid, and perhaps plate tectonics. Abundant liquid water favors both life and plate tectonics. Ocean is required for early evolution of diverse single-celled organisms, then colonies of cells which specialized further to form guts, ap- pendages, and sensory organisms up to the complexity of fish （central nervous system, appendages, eyes）. Large expanses of dry land also begin in the ocean, today produced above subduction zones in j.venile arcs and by their coalescence to form continents, although it is not clear that plate tectonics was required to create continental crust on Earth. Dry land of continents is required for further evolution of technological species, where modification of appendages for grasping and manipulating, and improve- ment of eyes and central nervous system could be perfected. These bioassets allowed intelligent crea- tures to examine the night sky and wonder, the beginning of abstract thinking, including religion and science. Technology arises from the exigencies of daily living such as tool-making, agriculture, clothing, and weapons, but the pace of innovation accelerates once it is allied with science. Finally, the importance of plate tectonics for devel

关键词： Plate tectonics Exoplanets Planetary science Intelligent life

Origin and evolution of palaeokarst within the Lower Ordovician (Ibexian) Goodwin Formation (Pogonip Group)

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j.urnal of Palaeogeography 2012年第1期1卷 57-69页

作者： robert j. Kervin Adam D. Woods Department of Geological Sciences California State University Fullerton P.O. Box 6850 Fullerton CA 92834-6850 USA Wapiti Energy 800 Gessner Rd. Suite 700 Houston TX 77024 USA

Palaeokarst within the Lower to Middle Ordovician Goodwin Formation, Pogonip Group (upper Ibexian-lower Whiterockian) was examined in detail at Meiklej.hn Peak, Nevada USA in order to determine its origin, evolution, and relationship to sea level change. Detailed outcrop and petrographic examination of dolostone breccias and host rock reveals that palaeokarst was formed and affected by two distinct cycles of sea level change. A relative transgression resulted in deposition of lagoonal, ooid shoal, and shallow subtidal facies as sea level rose. Exposure of the carbonate platform led to the formation of multiple phreatic caves below the water table, as well as the development of numerous vadose conduits from the downward percolation of meteoric waters. Vadose water flow through early cave-wall and cave-roof collapse breccias resulted in rounding of smaller breccias clasts via physical transport and corrosion, while subsidence of subsurface karst led to the formation of a palaeodoline at the exposure surface. A second relative transgression deposited lagoonal sediments over the older karst; subsequent re-exposure of the carbonate platform resulted in the development of small breccia pockets as well as grikes within the youngest lagoonal sediments, and may have led to further corrosion of the older, deeper subsurface karst. The distal location of the study area within the carbonate platform suggests karst formation was the result of a substantial drop in relative sea level; the presence of multiple generations of palaeokarst imply that at least two higher-frequency cycles of sea-level change overprint the larger regression.

关键词： palaeokarst Ordovician carbonates breccia Great Basin

Psychology(4E) / 4th ed.

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