11,717 research outputs found

    Assessing student perceptions of the Pharm.D. degree at a private tertiary medical university in India

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    Background: Pharmacy education in India has expanded to include the Doctorate of Pharmacy degree (Pharm.D.). With clinical practice in early development, job opportunities in India are limited. Graduates often consider pharmacy opportunities abroad. Aims: This study compares Indian students’ career aspirations related to the Pharm.D. degree before and after beginning their programmes. Methods: A 5-point Likert scale paper survey with open ended questions was distributed to all Pharm.D. students (Year 1- 6) at a medical university in India. Results: With a response rate of 83% (144/173), over half of the students’ primary goal was to pursue careers abroad post-graduation (54.2% before, 51.4% after). Data from the last three graduating classes indicated that 28.3% travelled abroad for future studies while 62.3% secured positions in India. Conclusions: Opportunities abroad remain challenging for Indian trained Pharm.D.s’; graduates may consider the expanding clinical opportunities in India

    The Effect of Zonally Asymmetric Ozone Heating on the Northern Hemisphere Winter Polar Stratosphere

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    [1] Previous modeling studies have found significant differences in winter extratropical stratospheric temperatures depending on the presence or absence of zonally asymmetric ozone heating (ZAOH), yet the physical mechanism causing these differences has not been fully explained. The present study describes the effect of ZAOH on the dynamics of the Northern Hemisphere extratropical stratosphere using an ensemble of free-running atmospheric general circulation model simulations over the 1 December - 31 March period. We find that the simulations including ZAOH produce a significantly warmer and weaker stratospheric polar vortex in mid-February due to more frequent major stratospheric sudden warmings compared to the simulations using only zonal mean ozone heating. This is due to regions of enhanced Eliassen-Palm flux convergence found in the region between 40°N–70°N latitude and 10–0.05 hPa. These results are consistent with changes in the propagation of planetary waves in the presence of ZAOH predicted by an ozone-modified refractive index

    Hook-Shape Immanant Characters from Stanley-Stembridge Characters

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    We consider the Schur-positivity of monomial immanants of Jacobi-Trudi matrices, in particular whether a non-negative coefficient of the trivial Schur function implies non-negative coefficients for other Schur functions in said immanants. We prove that this true for hook-shape Schur functions using combinatorial methods in a representation theory setting. Our main theorem proves that hook-shape immanant characters can be written as finite non-negative integer sums of Stanley-Stembridge characters, and provides an explicit combinatorial formula for these sums. This resolves a special case of a longstanding conjecture of Stanley and Stembridge that posits such a sum exists for all immanant characters. We also provide several simplifications for computing immanant characters, and several corollaries applying the main result to cases where the coefficient of the trivial Schur function in monomial immanants of Jacobi-Trudi matrices is known to be non-negative.Comment: 22 page

    MEMS-Based Terahertz Photoacoustic Chemical Sensing System

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    Advancements in microelectromechanical system (MEMS) technology over the last several decades has been a driving force behind miniaturizing and improving sensor designs. In this work, a specialized cantilever pressure sensor was designed, modeled, and fabricated to investigate the photoacoustic (PA) response of gases to terahertz (THz) radiation under low-vacuum conditions associated with high-resolution spectroscopy. Microfabricated cantilever devices made using silicon-on-insulator (SOI) wafers were tested in a custom-built test chamber in this first ever demonstration of a cantilever-based PA chemical sensor and spectroscopy system in the THz frequency regime. The THz radiation source was amplitude modulated to excite acoustic waves in the chamber, and PA molecular spectroscopy of a gas species was performed. An optical measurement technique was used to evaluate the PA effect on the cantilever sensor; a laser beam was reflected off the cantilever tip and through an iris to a photodiode. As the cantilever movement deflected the laser beam, the beam was clipped by an iris and generated the PA signal. Experimental data indicated a predominantly linear response in signal amplitude from the photodiode measurement technique, which directly correlated to measured cantilever deflections. Using the custom-designed PA chamber and MEMS cantilever sensor, excellent low-pressure PA spectral data of methyl cyanide (CH3CN) at 2 to 40 mTorr range has been obtained. At low chamber pressures, the sensitivity of our system was 1.97 × 10−5 cm−1 and had an excellent normalized noise equivalent absorption (NNEA) coefficient of 1.39 × 10−9 cm−1 W Hz-½ using a 0.5 s signal averaging time

    VICAR-DIGITAL image processing system

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    Computer program corrects various photometic, geometric and frequency response distortions in pictures. The program converts pictures to a number of elements, with each elements optical density quantized to a numerical value. The translated picture is recorded on magnetic tape in digital form for subsequent processing and enhancement by computer

    Terahertz Photoacoustic Spectroscopy Using an MEMS Cantilever Sensor

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    In this paper, a microelectromechanical systems cantilever sensor was designed, modeled, and fabricated to measure the photoacoustic (PA) response of gases under very low vacuum conditions. The micromachined devices were fabricated using silicon-on-insulator wafers and then tested in a custom-built, miniature, vacuum chamber during this first-ever demonstration. Terahertz radiation was amplitude modulated to excite the gas under test and perform PA molecular spectroscopy. Experimental data show a predominantly linear response that directly correlates measured cantilever deflection to PA signals. Excellent low pressure (i.e., 2-40 mTorr) methyl cyanide PA spectral data were collected resulting in a system sensitivity of 1.97 × 10 -5 cm -1 and a normalized noise equivalent absorption coefficient of 1.39 × 10 -9 cm -1 W Hz -1/2

    A Solvable Model for Decoupling of Interacting Clusters

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    We consider M clusters of interacting particles, whose in-group interactions are arbitrary, and inter-group interactions are approximated by oscillator potentials. We show that there are masses and frequencies that decouple the in-group and inter-group degrees of freedom, which reduces the initial problem to M independent problems that describe each of the relative in-group systems. The dynamics of the M center-of-mass coordinates is described by the analytically solvable problem of M coupled harmonic oscillators. This paper derives and discusses these decoupling conditions. Furthermore, to illustrate our findings, we consider a charged impurity interacting with a ring of ions. We argue that the impurity can be used to probe the center-of-mass dynamics of the ions.Comment: Version accepted for publication in EP
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