Improved pulse shape discriminator for fast neutron-gamma ray detection system

Discriminator in nuclear particle detection system distinguishes nuclear particle type and energy among many different nuclear particles. Discriminator incorporates passive, linear circuit elements so that it will operate over a wide dynamic range

The Achille J. St. Onge Papers

Achille St. Onge (1913-1978) was a publisher of miniature books. Publication of miniatures was a hobby as he worked in Worcester for many years at a forge company, then at an envelope company. He selected the work to be published, poured over the type selection, chose the cover layouts, and decided the color and style of the binding. All of the miniatures, are printed on handwoven rag paper. The books are edged in gold with decorative end papers and are bound in genuine leather. St. Onge\u27s papers include correspondence with authors, printers, and the subjects of some of the books. Special Collections also owns copies of all 48 of St. Onge\u27s books

Phase transition of the susceptible-infected-susceptible dynamics on time-varying configuration model networks

We present a degree-based theoretical framework to study the susceptible-infected-susceptible (SIS) dynamics on time-varying (rewired) configuration model networks. Using this framework, we provide a detailed analysis of the stationary state that covers, for a given structure, every dynamic regimes easily tuned by the rewiring rate. This analysis is suitable for the characterization of the phase transition and leads to three main contributions. (i) We obtain a self-consistent expression for the absorbing-state threshold, able to capture both collective and hub activation. (ii) We recover the predictions of a number of existing approaches as limiting cases of our analysis, providing thereby a unifying point of view for the SIS dynamics on random networks. (iii) We reinterpret the concept of hub-dominated phase transition. Within our framework, it appears as a heterogeneous critical phenomenon : observables for different degree classes have a different scaling with the infection rate. This leads to the successive activation of the degree classes beyond the epidemic threshold.Comment: 14 pages, 11 figure

Basement-cover relations and internal structure of the Cape Smith klippe: A 1.9 Ga greenstone belt in northern Quebec, Canada

The Cape Smith Belt is a 380x60 km tectonic klippe composed of greenschistto amphibolite-grade mafic and komatiitic lava flows and fine-grained quartzose sediment, intruded by minor syn- to post-tectonic granitoids. Previously studied transects in areas of relatively high structural level show that the belt is constructed of seven or more north-dipping thrust sheets which verge toward the Superior Province (Archean) foreland in the south and away from an Archean basement massif (Kovik Antiform) external to the Trans-Hudson Orogen (Early Proterozoic) in the north. A field project (mapping and structural-stratigraphic-metamorphic studies) directed by MRS was begun in 1985 aimed at the structurally deeper levels of the belt and underlying basement, which are superby exposed in oblique cross-section (12 km minimum structural relief) at the west-plunging eastern end of the belt. Mapping now complete of the eastern end of the belt confirms that all of the metavolcanic and most of the metasedimentary rocks are allochthonous with respect to the Archean basement, and that the thrusts must have been rooted north of Kovik Antiform. The main findings follow

Sitagliptin as combination therapy in the treatment of type 2 diabetes mellitus

The American Diabetes Association and The European Association for the Study of Diabetes recommend metformin as the initial agent of choice in the treatment of type 2 diabetes mellitus. Unfortunately, most patients require multiple medications to obtain glycemic control. One of the newest additions to the antidiabetic armamentarium is the class of drugs known as dipeptidyl-peptidase IV (DPP-IV) inhibitors. This novel approach focuses on harnessing the beneficial effects of GLP-1, an incretin hormone released from the gut postprandially. The first DPP-IV inhibitor approved in the United States was sitagliptin. It has been studied in both monotherapy and combination therapy. Combination studies with metformin realize a hemoglobin A1c reduction of 0.65%–1.1%. The combination of the two has a modest positive effect on body weight with the convenience of an oral route of administration. It has also been shown to be highly tolerable, efficacious and with little risk of hypoglycemia. This review will focus on combination therapy with sitagliptin with emphasis on combination with metformin

Localization, epidemic transitions, and unpredictability of multistrain epidemics with an underlying genotype network

Mathematical disease modelling has long operated under the assumption that any one infectious disease is caused by one transmissible pathogen spreading among a population. This paradigm has been useful in simplifying the biological reality of epidemics and has allowed the modelling community to focus on the complexity of other factors such as population structure and interventions. However, there is an increasing amount of evidence that the strain diversity of pathogens, and their interplay with the host immune system, can play a large role in shaping the dynamics of epidemics. Here, we introduce a disease model with an underlying genotype network to account for two important mechanisms. One, the disease can mutate along network pathways as it spreads in a host population. Two, the genotype network allows us to define a genetic distance across strains and therefore to model the transcendence of immunity often observed in real world pathogens. We study the emergence of epidemics in this model, through its epidemic phase transitions, and highlight the role of the genotype network in driving cyclicity of diseases, large scale fluctuations, sequential epidemic transitions, as well as localization around specific strains of the associated pathogen. More generally, our model illustrates the richness of behaviours that are possible even in well-mixed host populations once we consider strain diversity and go beyond the "one disease equals one pathogen" paradigm

Glacial geomorphology of the northern Kivalliq region, Nunavut, Canada, with an emphasis on meltwater drainage systems

This paper presents a glacial geomorphological map of glacial lineations, ribbed terrain, moraines, meltwater channels (subglacial and ice-marginal/proglacial), eskers, glaciofluvial deposits, ice-contact outwash fans and deltas and abandoned shorelines on the bed of the former Laurentide Ice Sheet in northern Canada. Mapping was compiled from satellite imagery and digital elevation data and landforms were digitised directly into a Geographical Information System. The map reveals a complex glacial history characterised by multiple ice-flow events, including fast-flowing ice-streams. Moraines record a series of pauses or re-advances during overall SE retreat towards the Keewatin Ice Divide. The distribution of subglacial meltwater landforms indicates that several distinctive scales and modes of drainage system operated beneath the retreating ice sheet. This includes a large (>100 km) integrated network of meltwater channels, eskers, ice-contact outwash fans and deltas and glaciofluvial deposits that originates at the northern edge of Aberdeen Lake. The map comprises zone 66 of the Canadian National Topographic System, which encompasses an area of 160,000 km2. It is presented at a scale of 1:500,000 and is designed to be printed at A0 size

Multiple tutorial-based assessments: a generalizability study

BACKGROUND: Tutorial-based assessment commonly used in problem-based learning (PBL) is thought to provide information about students which is different from that gathered with traditional assessment strategies such as multiple-choice questions or short-answer questions. Although multiple-observations within units in an undergraduate medical education curriculum foster more reliable scores, that evaluation design is not always practically feasible. Thus, this study investigated the overall reliability of a tutorial-based program of assessment, namely the Tutotest-Lite. METHODS: More specifically, scores from multiple units were used to profile clinical domains for the first two years of a system-based PBL curriculum. RESULTS: G-Study analysis revealed an acceptable level of generalizability, with g-coefficients of 0.84 and 0.83 for Years 1 and 2, respectively. Interestingly, D-Studies suggested that as few as five observations over one year would yield sufficiently reliable scores. CONCLUSIONS: Overall, the results from this study support the use of the Tutotest-Lite to judge clinical domains over different PBL units

Universality of the stochastic block model

Mesoscopic pattern extraction (MPE) is the problem of finding a partition of the nodes of a complex network that maximizes some objective function. Many well-known network inference problems fall in this category, including, for instance, community detection, core-periphery identification, and imperfect graph coloring. In this paper, we show that the most popular algorithms designed to solve MPE problems can in fact be understood as special cases of the maximum likelihood formulation of the stochastic block model (SBM), or one of its direct generalizations. These equivalence relations show that the SBM is nearly universal with respect to MPE problems.Comment: 13 pages, 4 figure