Personal Research Sets the Stage for Change

Starting in 2011, implementation of Personal Research Sessions, or PRS, not only showed librarians at College of the Holy Cross the success of one-on-one research appointments, but also led the reference program on a path of service-centered changes. This path includes fewer hours on the physical desk, a system of on-call reference shifts, an increase in reference student worker training, a semester-to-semester increase in PRS, and new goals for assessment. We discuss the state of student research at Holy Cross and our approach to reference servic

Hypothermia Due to an Ascending Impairment of Shivering in Hyperacute Experimental Allergic Encephalomyelitis in the Lewis Rat

Severe hypothermia and an ascending impairment of shivering are previously undescribed clinical signs in hyperacute experimental allergic encephalomyelitis (EAE) in the Lewis rat. These occurred in hyperacute EAE induced by inoculation with guinea pig spinal cord homogenate and heat-killed Bordetella pertussis. Hypothermia was first detected on day 6-7 post-inoculation, within 12-24 h of the onset of neurological signs, and became more severe as the disease progressed. Rectal temperatures less than or equal to 30 degrees C were common at ambient temperatures of 19-22 degrees C. Shivering was assessed by palpation and by cold tremor electromyography. Shivering was absent in the tail by day 6-7 post-inoculation. The impairment then progressed to affect the hindlimbs, thorax and occasionally the forelimbs. Shivering was absent in hindlimbs with only mild or moderate weakness. Histological studies revealed perivascular inflammation with polymorphonuclear and mononuclear cells, oedema, fibrin deposition, haemorrhage, primary demyelination and axonal degeneration in the spinal cord, dorsal root ganglia and spinal roots. The brainstem was also involved but the cerebral hemispheres, including the hypothalamus, were spared. The close relationship between the severity of hypothermia and the extent of shivering impairment indicates that reduced shivering is an important cause of hypothermia in hyperacute EAE. It is concluded that this impairment of shivering is due not to hypothalamic damage but to lesions elsewhere in the central and peripheral nervous systems

Risk of hepatocellular carcinoma in chronic hepatitis B: Assessment and modification with current antiviral therapy

SummaryIn the treatment of chronic hepatitis B (CHB), the ultimate goal is preventing hepatitis B virus (HBV)-associated liver disease, including hepatocellular carcinoma (HCC). Recently published studies show that in CHB patients treated with the currently recommended first-line nucleos(t)ide analogs (NAs) entecavir or tenofovir, annual HCC incidences range from 0.01% to 1.4% in non-cirrhotic patients, and from 0.9% to 5.4% in those with cirrhosis. In Asian studies including matched untreated controls, current NA therapy consistently resulted in a significantly lower HCC incidence in patients with cirrhosis, amounting to an overall HCC risk reduction of ∼30%; in non-cirrhotic patients, HCC risk reduction was overall ∼80%, but this was only observed in some studies. For patients of Caucasian origin, no appropriate comparative studies are available to date to evaluate the impact of NA treatment on HCC. Achievement of a virologic response under current NA therapy was associated with a lower HCC risk in Asian, but not Caucasian studies. Studies comparing entecavir or tenofovir with older NAs generally found no difference in HCC risk reduction between agents, except for one study which used no rescue therapy in patients developing lamivudine resistance. Overall, these data indicate that with the current, potent NAs, HCC risk can be reduced but not eliminated, probably due to risk factors that are not amenable to change by antiviral therapy, or events that may have taken place before treatment initiation. Validated pre- and on-therapy HCC risk calculators that inform the best practice for HCC surveillance and facilitate patient counseling would be of great practical value

Faraday rotation spectra of bismuth-substituted ferrite garnet films with in-plane magnetization

Single crystalline films of bismuth-substituted ferrite garnets have been synthesized by the liquid phase epitaxy method where GGG substrates are dipped into the flux. The growth parameters are controlled to obtain films with in-plane magnetization and virtually no domain activity, which makes them excellently suited for magnetooptic imaging. The Faraday rotation spectra were measured across the visible range of wavelengths. To interprete the spectra we present a simple model based on the existence of two optical transitions of diamagnetic character, one tetrahedral and one octahedral. We find excellent agreement between the model and our experimental results for photon energies between 1.77 and 2.53 eV, corresponding to wavelengths between 700 and 490 nm. It is shown that the Faraday rotation changes significantly with the amount of substituted gallium and bismuth. Furthermore, the experimental results suggest that the magnetooptic response changes linearly with the bismuth substitution.Comment: 15 pages, 6 figures, published in Phys. Rev.

Peculiarities in the behavior of the entropy diameter for molecular liquids as the reflection of molecular rotations and the excluded volume effects

The behavior of the diameter of the coexistence curve in terms of the entropy and the corresponding diameter are investigated. It is shown that the diameter of the coexistence curve in term of the entropy is sensitive to the change in the character of the rotational motion of the molecule in liquid phase which is governed by the short range correlations. The model of the compressible effective volume is proposed to describe the phase coexistence both in terms of the density and the entropy.Comment: 22 pages, 8 figures, 3 Table

Flux of atmospheric muons: Comparison between AIRES simulations and CAPRICE98 data

We report on a comparison between the flux of muons in the atmosphere measured by the CAPRICE98 experiment and simulations performed with the air shower simulation program AIRES. To reduce systematic uncertainties we have used as input the primary fluxes of protons and helium nuclei also measured by the CAPRICE98 experiment. Heavy nuclei are also taken into account in the primary flux, and their contribution to the muon flux is discussed. The results of the simulations show a very good agreement with the experimental data, at all altitudes and for all muon momenta. With the exception of a few isolated points, the relative differences between measured data and simulations are smaller than 20 %; and in all cases compatible with zero within two standard deviations. The influence of the input cosmic ray flux on the results of the simulations is also discussed. This report includes also an extensive analysis of the characteristics of the simulated fluxes.Comment: Accepted for publication in Physical Review

Saturn's icy satellites and rings investigated by Cassini - VIMS. III. Radial compositional variability

In the last few years Cassini-VIMS, the Visible and Infared Mapping Spectrometer, returned to us a comprehensive view of the Saturn's icy satellites and rings. After having analyzed the satellites' spectral properties (Filacchione et al. (2007a)) and their distribution across the satellites' hemispheres (Filacchione et al. (2010)), we proceed in this paper to investigate the radial variability of icy satellites (principal and minor) and main rings average spectral properties. This analysis is done by using 2,264 disk-integrated observations of the satellites and a 12x700 pixels-wide rings radial mosaic acquired with a spatial resolution of about 125 km/pixel. The comparative analysis of these data allows us to retrieve the amount of both water ice and red contaminant materials distributed across Saturn's system and the typical surface regolith grain sizes. These measurements highlight very striking differences in the population here analyzed, which vary from the almost uncontaminated and water ice-rich surfaces of Enceladus and Calypso to the metal/organic-rich and red surfaces of Iapetus' leading hemisphere and Phoebe. Rings spectra appear more red than the icy satellites in the visible range but show more intense 1.5-2.0 micron band depths. The correlations among spectral slopes, band depths, visual albedo and phase permit us to cluster the saturnian population in different spectral classes which are detected not only among the principal satellites and rings but among co-orbital minor moons as well. Finally, we have applied Hapke's theory to retrieve the best spectral fits to Saturn's inner regular satellites using the same methodology applied previously for Rhea data discussed in Ciarniello et al. (2011).Comment: 44 pages, 27 figures, 7 tables. Submitted to Icaru