Characterization and Scaling of MOS Flip Flop Performance in Synchronizer Applications

The measured and calculated values of t he Flip Flop parameters needed to specify synchronizer reliability are presented for 3 different depletion-load, silicon gate, NMOS, R-S Flip Flop circuits with gate lengths ranging from 6μm to 4.2μm. Estimates of the probability of synchronizer failure to resolve within allowed or desired times can be determined from these parameters

Using Exploratory Focus Groups to Inform the Development of Targeted COPD Self-Management Education DVDs for Rural Patients

This exploratory study assessed the self-management learning needs, experiences, and perspectives of COPD patients treated at a Certified Federal Rural Health Clinic to inform the development of a COPD self-management DVD. A purposive, homogeneous sample of COPD patients participated in focus group interviews. Data from these interviews were referenced to edit a library of Rvision COPD self-management DVDs into a single condensed DVD containing only the most pertinent self-management topics. Patients reported a lack of knowledge and skill development related to purse lipped breathing, controlled coughing, and stress management; while medication management skills were found to be quite adequate. Engaging rural communities in formal qualitative inquiries to describe COPD specific needs for self-management may lead to future use of educational technologies aimed at improving quality of life for these rural, hard to reach populations

The development of flash tube detectors for high energy physics

The work reported in this thesis describes the development of a new flash tubs detector particularly suited to nuclear accelerator experimentation, and specifically considers its application to the detection of high energy photons. A flash tube detector has been developed with characteristics which permit efficient operation in a background radiation flux of about 10 (^5) particles/tube/second and at repetition rates of the order 1 KH (_z). The viability of its application to accelerator physics was investigated and verified using the DNPL e (^+) accelerator beam with a chamber containing digitized flash tubes linked to a computerized data acquisition system. Application of the device to the detection of high energy photons has also been made with the chamber, by simulating photon induced electromagnetic showers with positrons, in the energy range 0.5 - 4.0 GeV. Results from this series of experiments have shown that both energy and spatial information may be obtained from a chamber constructed with large diameter tubas and of small overall size. The energy and spatial resolution of the device has been measured as a function of energy and shown to compare favourably with more complex and expensive techniques. Analysis of the shower data has also demonstrated that several improvements are possible. These improvements have been incorporated in the design of a new chamber capable of operating at repetition rates up to lKHz and which should measure the energy and trajectory of incident photons with a greater precision than is possible with many conventional instruments

Developing high-quality meteorological data for East and West Africa from merged sources

Assessments of agricultural productivity and food security require process-based crop models to provide predictions of yields and diagnose past variations in the context of anthropogenic and climate factors. These models need detailed meteorological data as input, including precipitation, temperature, humidity, solar radiation and windspeed. This project aimed to apply existing methods to merge in situ, remotely sensed and modeled data sources in East and West Africa to produce high-quality daily meteorological data over at least 30 years. Specific objectives included: evaluation of the error structure of the dataset, its temporal and spatial characteristics and consistency and its suitability for forcing crop models, and to provide a framework for merging new data, in particular from the local stations of regional African partners, ensuring consistency across time and space and among variables, as well as the best use of information. The work successfully created a 10 kilometre, daily meteorological dataset for East and West Africa for the period 1979–2008, based on the National Centers for Environmental Prediction-National Center for Atmospheric Research (NCEP–NCAR) reanalysis (NNR), merged with observational datasets, including the monthly gridded precipitation and temperature product of the University of East Anglia’s Climate Research Unit (CRU), the NASA Langley Surface Radiation Budget (SRB) product, and station data from the Global Summary of the Day (GSOD) database

Application of shock tubes to transonic airfoil testing at high Reynolds numbers

Performance analysis of a gas-driven shock tube shows that transonic airfoil flows with chord Reynolds numbers of the order of 100 million can be produced, with limitations being imposed by the structural integrity of the facility or the model. A study of flow development over a simple circular arc airfoil at zero angle of attack was carried out in a shock tube at low and intermediate Reynolds numbers to assess the testing technique. Results obtained from schlieren photography and airfoil pressure measurements show that steady transonic flows similar to those produced for the same airfoil in a wind tunnel can be generated within the available testing time in a shock tube with properly contoured test section walls

An Interview with Dr. Ed Stehno, Education Professor: 1988 Cunningham Award Recipient

Transcribed interview with Dr. Ed Stehno, Education Professor and 1988 Cunningham Award Recipienthttps://scholars.fhsu.edu/ors/1230/thumbnail.jp

Orexin 2 Receptor Antagonists from Prefrontal Cortical Circuitry to Rodent Behavioral Screens

Orexin is a neuropeptide contained in neurons from several hypothalamic nuclei that project throughout the forebrain analogously to monoamines synthesized by brainstem nuclei. Orexin, like 5-hydroxytryptamine (5-HT), norepinephrine (NE), dopamine (DA), histamine and acetylcholine (ACh) exerts prominent effects on the sleep-wake cycle of all mammals. Activation of the orexin2 receptor appears to induce spontaneous excitatory synaptic currents (EPSCs) on layer V pyramidal neurons due to release of glutamate from thalamocortical terminals similar to activation of 5-HT2A and α1-adrenergic receptors. Layer V pyramidal cells are the major descending output cell in the prefrontal cortex with projections to the thalamus, striatum, amygdala, brainstem and spinal cord. In keeping with salient modulation of prefrontal cortical physiology, orexin2 receptor antagonists exert similar effects to 5-HT2A receptor antagonists in suppressing hallucinogen (e.g., DOI)-induced head twitches and producing antidepressant-like effects on the differential-reinforcement-of-low-rate 72-s (DRL 72-s) schedule of reinforcement. Currently, there is both negative and some preliminary positive evidence that blocking orexin2 receptors may result in antidepressant efficacy in patients with major depressive disorder. Overall, the treatment of mood disorders is an additional potential indication for orexin receptor antagonists beyond simply improving sleep

Une offre de services adaptée aux chercheurs

Ayant l'un des groupes de lecteurs les plus exigeants dans le monde scientifique et des ressources comparables à celles d'une collection de moyenne bibliothèque universitaire, le Service de l'Information Scientifique du CERN utilise toute sa créativité pour ne pas disparaître entre l'offre et la demande. Le CERN a pour but d'être un centre d'excellence dans le domaine de la physique des hautes energies et des technologies connexes. Le Service d'Information Scientifique réalise cet objectif en préservant la mémoire des développements de la physique et en appliquant les technologies avancées des sciences de l'information et du commerce électronique

The soil microbial community alters patterns of selection on flowering time and fitness‐related traits in Ipomoea purpurea

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154384/1/ajb21426.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154384/2/ajb21426_am.pd

Discovery of new Al-Cu-Fe minerals in the Khatyrka CV3 meteorite

Introduction: During a nanomineralogy investigation of the Khatyrka CV3 carbonaceous chondrite, we have identified two new alloy minerals (AlCu with a Pm-3m CsCl structure and Al_3Fe with a C2/m structure) and associated icosahedrite (quasicrystal Al_(63)Cu_(26)Fe_(11) with a five-fold symmetry) at micron scales in section 126A of USNM 7908. The section belongs to the larger Grain 126, which is one of the fragments recovered from an expedition to the Koryak Mountains in far eastern Russia in 2011 [1] as a result of a search for samples that would provide information on the origin of the quasicrystal mineral icosahedrite [2,3,4]. The recovered fragments have meteoritic (CV3-like) oxygen isotopic compositions and are identified collectively as coming from the Khatyrka meteorite [5], which formed 4.5 billion years ago during the earliest stages of the solar system. Khatyrka is unique, so far being the only meteorite to host metallic Al component