Case Western Reserve University

About: Case Western Reserve University is a education organization based out in Cleveland, Ohio, United States. It is known for research contribution in the topics: Population & Cancer. The organization has 54617 authors who have published 106568 publications receiving 5071613 citations. The organization is also known as: Case & Case Western.

Observation of the suppression of the flux of cosmic rays above 4x10(19) eV

Abstract: The energy spectrum of cosmic rays above 2.5 x 10;{18} eV, derived from 20,000 events recorded at the Pierre Auger Observatory, is described. The spectral index gamma of the particle flux, J proportional, variantE;{-gamma}, at energies between 4 x 10;{18} eV and 4 x 10;{19} eV is 2.69+/-0.02(stat)+/-0.06(syst), steepening to 4.2+/-0.4(stat)+/-0.06(syst) at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz'min.

A neural interface provides long-term stable natural touch perception.

Abstract: Touch perception on the fingers and hand is essential for fine motor control, contributes to our sense of self, allows for effective communication, and aids in our fundamental perception of the world. Despite increasingly sophisticated mechatronics, prosthetic devices still do not directly convey sensation back to their wearers. We show that implanted peripheral nerve interfaces in two human subjects with upper limb amputation provided stable, natural touch sensation in their hands for more than 1 year. Electrical stimulation using implanted peripheral nerve cuff electrodes that did not penetrate the nerve produced touch perceptions at many locations on the phantom hand with repeatable, stable responses in the two subjects for 16 and 24 months. Patterned stimulation intensity produced a sensation that the subjects described as natural and without “tingling,” or paresthesia. Different patterns produced different types of sensory perception at the same location on the phantom hand. The two subjects reported tactile perceptions they described as natural tapping, constant pressure, light moving touch, and vibration. Changing average stimulation intensity controlled the size of the percept area; changing stimulation frequency controlled sensation strength. Artificial touch sensation improved the subjects’ ability to control grasping strength of the prosthesis and enabled them to better manipulate delicate objects. Thus, electrical stimulation through peripheral nerve electrodes produced long-term sensory restoration after limb loss.

Measuring Trauma and Health Status in Refugees: A Critical Review

Abstract: ContextRefugees experience multiple traumatic events and have significant associated health problems, but data about refugee trauma and health status are often conflicting and difficult to interpret.ObjectivesTo assess the characteristics of the literature on refugee trauma and health, to identify and evaluate instruments used to measure refugee trauma and health status, and to recommend improvements.Data SourcesMEDLINE, PsychInfo, Health and PsychoSocial Instruments, CINAHL, and Cochrane Systematic Reviews (searched through OVID from the inception of each database to October 2001), and the New Mexico Refugee Project database.Study SelectionKey terms and combination operators were applied to identify English-language publications evaluating measurement of refugee trauma and/or health status.Data ExtractionInformation extracted for each article included author; year of publication; primary focus; type (empirical, review, or descriptive); and type/name and properties of instrument(s) included. Articles were excluded from further analyses if they were review or descriptive, were not primarily about refugee health status or trauma, or were only about infectious diseases. Instruments were then evaluated according to 5 criteria (purpose, construct definition, design, developmental process, reliability and validity) as described in the published literature.Data SynthesisOf 394 publications identified, 183 were included for further analyses of their characteristics; 91 (49.7%) included quantitative data but did not evaluate measurement properties of instruments used in refugee research, 78 (42.6%) reported on statistical relationships between measures (presuming validity), and 14 (7.7%) were only about statistical properties of instruments. In these 183 publications, 125 different instruments were used; of these, 12 were developed in refugee research. None of these instruments fully met all 5 evaluation criteria, 3 met 4 criteria, and 5 met only 1 of the criteria. Another 8 standard instruments were designed and developed in nonrefugee populations but adapted for use in refugee research; of these, 2 met all 5 criteria and 6 met 4 criteria.ConclusionsThe majority of articles about refugee trauma or health are either descriptive or include quantitative data from instruments that have limited or untested validity and reliability in refugees. Primary limitations to accurate measurement in refugee research are the lack of theoretical bases to instruments and inattention to using and reporting sound measurement principles.

Salmonella mutagenicity tests: II. Results from the testing of 270 chemicals.

Abstract: This publication includes data of Salmonella mutagenicity results on 270 coded chemicals, encompassing 329 tests performed by three laboratories under contract to the National Toxicology Program (NTP). The preincubation modification of the Salmonella/mammalian microsome assay was used to test chemicals in up to five Salmonella strains in the presence and absence of rat and hamster liver S-9. With a few exceptions, inter- and intralaboratory reproducibility was good.