Baffin Island Expedition, 1950: A Preliminary Report

Brief resume by the leader, of the personnel, itinerary, camps, transportation and program of an expedition sponsored by Arctic Institute of North America, Royal Canadian Air Force, Geological Survey of Canada, Swiss Foundation for Alpine Research and the Canadian Geographical Society, to the east coast of Baffin Island at Clyde settlement, May-Aug. 1950; with short "initial reports on progress" of the scientific studies..

Identifying the mechanisms underpinning recognition of structured sequences of action

© 2012 The Experimental Psychology SocietyWe present three experiments to identify the specific information sources that skilled participants use to make recognition judgements when presented with dynamic, structured stimuli. A group of less skilled participants acted as controls. In all experiments, participants were presented with filmed stimuli containing structured action sequences. In a subsequent recognition phase, participants were presented with new and previously seen stimuli and were required to make judgements as to whether or not each sequence had been presented earlier (or were edited versions of earlier sequences). In Experiment 1, skilled participants demonstrated superior sensitivity in recognition when viewing dynamic clips compared with static images and clips where the frames were presented in a nonsequential, randomized manner, implicating the importance of motion information when identifying familiar or unfamiliar sequences. In Experiment 2, we presented normal and mirror-reversed sequences in order to distort access to absolute motion information. Skilled participants demonstrated superior recognition sensitivity, but no significant differences were observed across viewing conditions, leading to the suggestion that skilled participants are more likely to extract relative rather than absolute motion when making such judgements. In Experiment 3, we manipulated relative motion information by occluding several display features for the duration of each film sequence. A significant decrement in performance was reported when centrally located features were occluded compared to those located in more peripheral positions. Findings indicate that skilled participants are particularly sensitive to relative motion information when attempting to identify familiarity in dynamic, visual displays involving interaction between numerous features

User-Centered Evaluation of a Discovery Layer System with Google Scholar

Discovery layer systems allow library users to obtain search results from multiple library resources and view results in a consistent format. The implementation of a discovery layer is expected to simplify users’ workflow of searching for scholarly information. Previous studies on discovery layer systems focused on functionality and content, but not quality of search results from the user’s perspective. The objective of this study was to obtain users’ assessment of search results of a discovery layer system (Ex Libris Primo®) and compare that with a widely used scholarly search tool (Google Scholar). Results showed that Primo’s search results relevancy is comparable to Google Scholar, but it received significantly lower usability and preference ratings. A number of usability issues of Primo were also identified from the study. Results of the study are used to improve the interface of Primo and adjust relevancy ranking options. The empirical method of search results assessment and feedback collection used in this study can be extended to similar user-centered system implementation and evaluation efforts

Baffin Island Expedition, 1953: A Preliminary Field Report

Contains description and brief summaries of results of the second Baffin Island Expedition of the Arctic Institute of North America, May-Sept. 1953. The 13-man party carried out a program in the Penny Highland region of Cumberland Peninsula, centering on Pangnirtung Pass. Glaciological work on the Penny Icecap and Highway Glacier included studies of glacier physics, seismic work, and meteorological observations on bedrock geology and structure are given. Corrie formation and the geomorphology of Pangnirtung Pass were studied. Specimens of local fauna were collected and biological studies of some species were made. Comparisons of the vegetation of Penny Highland and East and North Greenland were made through extensive plant collections. Eight peaks were climbed and their altitudes determined. A list of 17 new names approved by the Canadian Board on Geographical Names is appended

Lynch Syndrome Associated with Two MLH1 Promoter Variants and Allelic Imbalance of MLH1 Expression

© 2015 The Authors. **Human Mutation published by Wiley Periodicals, Inc. Lynch syndrome is a hereditary cancer syndrome caused by a constitutional mutation in one of the mismatch repair genes. The implementation of predictive testing and targeted preventative surveillance is hindered by the frequent finding of sequence variants of uncertain significance in these genes. We aimed to determine the pathogenicity of previously reported variants (c.-28A > G and c.-7C > T) within the MLH1 5â²untranslated region (UTR) in two individuals from unrelated suspected Lynch syndrome families. We investigated whether these variants were associated with other pathogenic alterations using targeted high-throughput sequencing of the MLH1 locus. We also determined their relationship to gene expr ession and epigenetic alterations at the promoter. Sequencing revealed that the c.-28A > G and c.-7C > T variants were the only potentially pathogenic alterations within the MLH1 gene. In both individuals, the levels of transcription from the variant allele were reduced to 50% compared with the wild-type allele. Partial loss of expression occurred in the absence of constitutional epigenetic alterations within the MLH1 promoter. We propose that these variants may be pathogenic due to constitutional partial loss of MLH1 expression, and that this may be associated with intermediate penetrance of a Lynch syndrome phenotype. Our findings provide further evidence of the potential importance of noncoding variants in the MLH1 5â²UTR in the pathogenesis of Lynch syndrome.Link_to_subscribed_fulltex

Formation of extended topological defects during symmetry breaking phase transitions in O(2) and O(3) models

The density of extended topological defects created during symmetry-breaking phase transitions depends on the ratio between the correlation length in the symmetric phase near $T_c$ and the winding length of the defects as determined by the momentaneous effective action after a typical relaxation time. Conservation of winding number in numerical simulations requires a suitable embedding of the field variables and the appropriate geometrical implementation of the winding density on the discrete lattice. We define a modified Kibble limit for the square lattice and obtain defect densities as functions of winding lengths in O(2) and O(3) models. The latter allows to observe formation of disoriented aligned domains within the easy plane. Their extent is severely limited by the momentaneous defect density during the course of the quench.Comment: 16 pages, 9 figure

Measurement of the scintillation time spectra and pulse-shape discrimination of low-energy beta and nuclear recoils in liquid argon with DEAP-1

The DEAP-1 low-background liquid argon detector was used to measure scintillation pulse shapes of electron and nuclear recoil events and to demonstrate the feasibility of pulse-shape discrimination (PSD) down to an electron-equivalent energy of 20 keV. In the surface dataset using a triple-coincidence tag we found the fraction of beta events that are misidentified as nuclear recoils to be $<1.4\times 10^{-7}$ (90% C.L.) for energies between 43-86 keVee and for a nuclear recoil acceptance of at least 90%, with 4% systematic uncertainty on the absolute energy scale. The discrimination measurement on surface was limited by nuclear recoils induced by cosmic-ray generated neutrons. This was improved by moving the detector to the SNOLAB underground laboratory, where the reduced background rate allowed the same measurement with only a double-coincidence tag. The combined data set contains $1.23\times10^8$ events. One of those, in the underground data set, is in the nuclear-recoil region of interest. Taking into account the expected background of 0.48 events coming from random pileup, the resulting upper limit on the electronic recoil contamination is $<2.7\times10^{-8}$ (90% C.L.) between 44-89 keVee and for a nuclear recoil acceptance of at least 90%, with 6% systematic uncertainty on the absolute energy scale. We developed a general mathematical framework to describe PSD parameter distributions and used it to build an analytical model of the distributions observed in DEAP-1. Using this model, we project a misidentification fraction of approx. $10^{-10}$ for an electron-equivalent energy threshold of 15 keV for a detector with 8 PE/keVee light yield. This reduction enables a search for spin-independent scattering of WIMPs from 1000 kg of liquid argon with a WIMP-nucleon cross-section sensitivity of $10^{-46}$ cm$^2$, assuming negligible contribution from nuclear recoil backgrounds.Comment: Accepted for publication in Astroparticle Physic

Brevi spunti sul d.lgs. n. 150/2009 e sulla sua applicabilità agli Enti locali

© 2014 Taylor & Francis Group, LLC. Gene silencing in cancer frequently involves hypermethylation and dense nucleosome occupancy across promoter regions. How a promoter transitions to this silent state is unclear. Using colorectal adenomas, we investigated nucleosome positioning, DNA methylation, and gene expression in the early stages of gene silencing. Genome-wide gene expression correlated with highly positioned nucleosomes upstream and downstream of a nucleosome-depleted transcription start site (TSS). Hypermethylated promoters displayed increased nucleosome occupancy, specifically at the TSS. We investigated 2 genes, CDH1 and CDKN2B, which were silenced in adenomas but lacked promoter hypermethylation. Instead, silencing correlated with loss of nucleosomes from the -2 position upstream of the TSS relative to normal mucosa. In contrast, permanent CDH1 silencing in carcinoma cells was characterized by promoter hypermethylation and dense nucleosome occupancy. Our findings suggest that silenced genes transition through an intermediary stage involving altered promoter nucleosome positioning, before permanent silencing by hypermethylation and dense nucleosome occupancy.Link_to_subscribed_fulltex

Relativistic Continuum Hartree Bogoliubov Theory for Ground State Properties of Exotic Nuclei

The Relativistic Continuum Hartree-Bogoliubov (RCHB) theory, which properly takes into account the pairing correlation and the coupling to (discretized) continuum via Bogoliubov transformation in a microscopic and self-consistent way, has been reviewed together with its new interpretation of the halo phenomena observed in light nuclei as the scattering of particle pairs into the continuum, the prediction of the exotic phenomena -- giant halos in nuclei near neutron drip line, the reproduction of interaction cross sections and charge-changing cross sections in light exotic nuclei in combination with the Glauber theory, better restoration of pseudospin symmetry in exotic nuclei, predictions of exotic phenomena in hyper nuclei, and new magic numbers in superheavy nuclei, etc. Recent investigations on new effective interactions, the density dependence of the interaction strengthes, the RMF theory on the Woods-Saxon basis, the single particle resonant states, and the resonant BCS (rBCS) method for the pairing correlation, etc. are also presented in some details.Comment: 79 pages. Prog. Part. Nucl. Phys. (2005) in pres