Resistivity and Hall measurements of thermoelectric materials

Instrumentation setup measures resistivity values between .000003 and 100,000 ohm-cm and Hall values between 0.2 and 10 billion cc/coulomb, with an absolute error of less than 5 percent. Results of measurement are given for 8 electrical brush specimens and pure silver

Determination of resistivity and Hall coefficient of semiconducting materials between 80 deg K and 375 deg K

Determination of resistivity and Hall coefficient of semiconductor material

American Education Through a Chinese Lens

This June, a group of faculty members from Gettysburg College and K-12 teachers from York and Adams Counties travelled to China for four weeks of intensive cultural and educational exchange. This Gettysburg Fulbright Group Project Abroad in China studied the cultural and historical foundations of the Chinese educational system, as well as how this system is changing. Participants studied the larger policy context of the Chinese system and how those policies play out in the classroom. (excerpt

Fulbright Magic: The Alchemy of an Intentional Experience Abroad

The Fulbright program is designed to facilitate cultural exchange and understanding, and Fulbright’s Group Projects Abroad allow small, focused cohorts of American teachers and scholars to travel and to learn together. In June 2017, a number of Gettysburg College faculty and K-12 teachers from South Central PA traveled to China to study points of similarity and disparity between the American and Chinese educational systems. Our program was crafted in a way to help us to understand Chinese culture and the realities of Chinese life; we were given the opportunity to view our experiences from the perspectives of our hosts and resident experts, not simply as tourists. (excerpt

Enhancement of K+ conductance improves in vitro the contraction force of skeletal muscle in hypokalemic periodic paralysis

An abnormal ratio between Na+ and K+ conductances seems to be the cause for the depolarization and paralysis of skeletal muscle in primary hypokalemic periodic paralysis. Recently we have shown that the k+ channel opener cromakalim hyperpolarizes mammalian skeletal muscle fibers. Now we have studied the effects of this drug on the twitch force of muscle biopsies from normal and diseased human skeletal muscle. Cromakalim had little effect on the twitch force of normal muscle whereas it strongly improved the contraction force of fibers from patients suffering from hypokalemic periodic paralysis. Recordings of intracellular K+ and Cl- activities in human muscle and isolated rat soleus muscle support the view that cromakalim enhances the membrane K+ conductance (gK+). These data indicate that K+ channel openers may have a beneficial effect in primary hypokalemic periodic paralysis

Evaluation of AAFE apparatus to measure residual and transient convection in zero-gravity

An evaluation apparatus which photographs convective and diffusive flows in crystal growth experiments is presented. Results in the following catagories are reported: (1) Human factors; (2) Electrical and mechanical; (3) Optical performance; and (4) Thermal performance

The broad emission-line region: the confluence of the outer accretion disc with the inner edge of the dusty torus

(Abridged) We investigate the observational characteristics of BLR geometries in which the BLR clouds bridge the gap, both in distance and scale height, between the outer accretion disc and the hot dust, forming an effective surface of a "bowl". The gas dynamics are dominated by gravity, and we include the effects of transverse Doppler shift, gravitational redshift and scale-height dependent macro-turbulence. Our simple model reproduces many of the phenomena observed in broad emission-line variability studies, including (i) the absence of response in the core of the optical recombination lines on short timescales, (ii) the enhanced red-wing response on short timescales, (iii) differences between the measured delays for the HILs and LILs, and (iv) identifies turbulence as a means of producing Lorentzian profiles (esp. for LILs) in low inclination systems, and for suppressing significant continuum--emission-line delays between the line wings and line core (esp. in LILs). A key motivation of this work was to reveal the physical underpinnings of the reported measurements of SMBH masses and their uncertainties. We find that SMBH masses derived from measurements of the fwhm of the mean and rms profiles show the closest correspondence between the emission lines in a single object, even though the emission line fwhm is a more biased mass indicator with respect to inclination. The predicted large discrepancies in the SMBH mass estimates between emission lines at low inclination, as derived using the line dispersion, we suggest may be used as a means of identifying near face-on systems. Our general results do not depend on specific choices in the simplifying assumptions, but are in fact generic properties of BLR geometries with axial symmetry that span a substantial range in radially-increasing scale height supported by turbulence, which then merge into the inner dusty TOR.Comment: 29 pages, 23 figures and 1 tabl

The cutaneous 'rabbit' illusion affects human primary sensory cortex somatopically

We used functional magnetic resonance imaging (fMRI) to study neural correlates of a robust somatosensory illusion that can dissociate tactile perception from physical stimulation. Repeated rapid stimulation at the wrist, then near the elbow, can create the illusion of touches at intervening locations along the arm, as if a rabbit hopped along it. We examined brain activity in humans using fMRI, with improved spatial resolution, during this version of the classic cutaneous rabbit illusion. As compared with control stimulation at the same skin sites (but in a different order that did not induce the illusion), illusory sequences activated contralateral primary somatosensory cortex, at a somatotopic location corresponding to the filled-in illusory perception on the forearm. Moreover, the amplitude of this somatosensory activation was comparable to that for veridical stimulation including the intervening position on the arm. The illusion additionally activated areas of premotor and prefrontal cortex. These results provide direct evidence that illusory somatosensory percepts can affect primary somatosensory cortex in a manner that corresponds somatotopically to the illusory percept

Using Popular Media and a Collaborative Approach to Teaching Grounded Theory Research Methods

Popular movies were used in a doctoral-level qualitative research methods course as a way to help students learn about how to collect and analyze qualitative observational data in order to develop a grounded theory. The course was designed in such a way that collaboration was central to the generation of knowledge. Using media depictions had the practical advantage of enabling the group to create fieldnotes from a common set of data collected simultaneously in a short period of time. Fictional representations in popular media can provide the basis to learn about both the methods and foundational assumptions for conducting qualitative research, including the challenges of bracketing prior assumptions