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Jae D. Chang,Bryan Falk
E-Preservation Science , 2009,
Abstract: This paper presents the findings of a case study of a rarebooks archive that seeks to balance the environmentalneeds of both the collection and users of the librar y. Withthe aid of physical data collection and computer simulationsusing computational fluid dynamics, the indoor environmentalperformance of the archive was analyzed. Datawas collected on the archive’s air temperature, humidity,light level, volatile organic compounds, particulates, mold,and formaldehyde. In addition, the mechanical system wasinvestigated as was the design and construction of thearchive and its maintenance and operation. Specific areasof investigation were ventilation effectiveness, temperaturedistribution, pollutant concentration, and possibleindoor and outdoor sources of pollutants specific to theenvironment under investigation. Focus was placed onimproving the overall local mean age of air and minimizingpotential sources of pollutants as a result of maintenanceand design. This study provides some insight into howarchitects, preser vationists, conservators, and environmentalengineers can collaborate to design more environmentallysound archive spaces.
Mechanical Weyl Modes in Topological Maxwell Lattices
D. Zeb Rocklin,Bryan Gin-ge Chen,Martin Falk,Vincenzo Vitelli,T. C. Lubensky
Physics , 2015,
Abstract: Topological mechanical structures exhibit robust properties protected by topological invariants. In this letter, we study a family of deformed square lattices that display topologically protected zero-energy bulk modes analogous to the massless fermion modes of Weyl semimetals. Our findings apply to sufficiently complex lattices satisfying the Maxwell criterion of equal numbers of constraints and degrees of freedom. We demonstrate that such systems exhibit pairs of oppositely charged Weyl points, corresponding to zero-frequency bulk modes, that can appear at the origin of the Brillouin zone and move away to the zone edge (or return to the origin) where they annihilate. We prove that the existence of these Weyl points leads to a wavenumber-dependent count of topological mechanical states at free surfaces and domain walls.
Simulating the Common Envelope Phase of a Red Giant Using SPH and Uniform Grid Codes
Jean-Claude Passy,Orsola De Marco,Chris L. Fryer,Falk Herwig,Steven Diehl,Jeffrey S. Oishi,Mordecai-Mark Mac Low,Greg L. Bryan,Gabriel Rockefeller
Physics , 2011, DOI: 10.1088/0004-637X/744/1/52
Abstract: We use three-dimensional hydrodynamical simulations to study the rapid infall phase of the common envelope interaction of a red giant branch star of mass equal to 0.88 \msun and a companion star of mass ranging from 0.9 down to 0.1 \msun. We first compare the results obtained using two different numerical techniques with different resolutions, and find overall very good agreement. We then compare the outcomes of those simulations with observed systems thought to have gone through a common envelope. The simulations fail to reproduce those systems in the sense that most of the envelope of the donor remains bound at the end of the simulations and the final orbital separations between the donor's remnant and the companion, ranging from 26.8 down to 5.9 \rsun, are larger than the ones observed. We suggest that this discrepancy vouches for recombination playing an essential role in the ejection of the envelope and/or significant shrinkage of the orbit happening in the subsequent phase.
Production of MgO-X Refractory Material with Cellular Matrix by Colloidal Processing  [PDF]
Wagner da Silveira, Guido Falk
Low Carbon Economy (LCE) , 2012, DOI: 10.4236/lce.2012.323012
Abstract: The production in the siderurgy and foundry industry has changed considerably in the past years. Despite the new technologies and process, the use of magnesia carbon refractory remains constant. Namely the magnesia carbon refractory is widely used due low-priced cost, high refractivity, excellent corrosion resistance, thermal shock resistance, low thermal expansion, high slag penetration resistance and low wettability. The main disadvantages of use magnesia carbon refractories are the high carbon oxidation susceptibility and the formation CO and CO2 gases. As a result, tonne of CO and CO2 are expelled to the atmosphere. The use of open cell carbon-foam magnesia composite for refractory application can offer a substitute for the traditional refractory material since the high carbon content can be minored and the low mechanical strength and poor oxidation resistance of these materials can be improved.
The Effects of Food Neophobia and Food Neophilia on Diet and Metabolic Processing  [PDF]
August Capiola, Bryan Raudenbush
Food and Nutrition Sciences (FNS) , 2012, DOI: 10.4236/fns.2012.310183
Abstract: Past research shows that food neophobics (those individuals reluctant to try novel foods) and food neophilics (those individuals overtly willing to try novel foods) differ in terms of sensory evaluations, psychophysical ratings, stimulus sampling, physiological responses, and genetic predispositions. The present study assessed whether such factors had an effect on participants’ dietary consumption and subsequent nutritional adequacy. One hundred and sixteen participants, aged 18 - 76 years, completed a food diary for three days as well as several eating-related questionnaires. Nutritional summaries and questionnaire scores were subjected to a multivariate analysis of covariance (MANCOVA) with participants being sorted into three groups depending on their Food Neophobia Score. These three groups consisted of food neophobics, average individuals, and food neophilics. Groups were found to differ significantly on dietary intake of 20 specific nutritional and caloric items, with food-neophobics typically having the lowest intake. Implications support the initial hypothesis of food neophobics having less nutritionally plentiful diets than food neophilics, thus leading food neophobics to have a nutritionally deficient diet. This finding is important since decrease in nutritional intake can result in health related deficiencies.
Early Initial Diagnosis of Gardner Syndrome in a 12-Year-Old Boy  [PDF]
Erich Bryan, Peter Kalina
Advances in Computed Tomography (ACT) , 2013, DOI: 10.4236/act.2013.21001

A 12-year-old boy presented to his primary care physician with a painful lump at the angle of the left mandible after being kicked in the jaw during a soccer game. Over the next 2 months the lesion became progressively firmer and fine needle aspiration was attempted. Results were non-diagnostic. Panorex examination revealed a calcified mass contiguous with the left angle of the mandible. Considerations were bony callus secondary to trauma versus a calcified hematoma. A maxillofacial CT showed multiple diffuse craniofacial osseous lesions including the clinically suspected region at the left angle of the mandible. Imaging findings were consistent with multiple craniofacial osteomas and workup for Gardner Syndrome was initiated. Genetic testing was subsequently positive for Familial Adenomatous Polyposis.

Instanton constituents in the O(3) model at finite temperature
Bruckmann, Falk
High Energy Physics - Phenomenology , 2007, DOI: 10.1103/PhysRevLett.100.051602
Abstract: It is shown that instantons in the O(3) model at finite temperature consist of fractional charge constituents and the (topological) properties of the latter are discussed.
Topological objects in QCD
Bruckmann, Falk
High Energy Physics - Phenomenology , 2007, DOI: 10.1140/epjst/e2007-00377-2
Abstract: Topological excitations are prominent candidates for explaining nonperturbative effects in QCD like confinement. In these lectures, I cover both formal treatments and applications of topological objects. The typical phenomena like BPS bounds, topology, the semiclassical approximation and chiral fermions are introduced by virtue of kinks. Then I proceed in higher dimensions with magnetic monopoles and instantons and special emphasis on calorons. Analytical aspects are discussed and an overview over models based on these objects as well as lattice results is given.
Exploring the QCD vacuum - (some) recent developments in confinement and topology
Bruckmann, Falk
High Energy Physics - Phenomenology , 2007,
Abstract: I start by giving a brief overview over new developments in the area of confinement and topology. As an example for the interrelations between topological objects, instantons at finite temperature are discussed. Then I focus on new insights into the structure of the QCD vacuum obtained through filtering methods, in particular those based on decompositions w.r.t. fermionic eigenmodes.
Benefits and risks of benzodiazepines and Z-drugs: comparison of perceptions of GPs and community pharmacists in Germany [Wie sch tzen deutsche Haus rzte und Apotheker Nutzen und Schaden von Benzodiazepinen und Z-Drugs ein?]
Hoffmann, Falk
GMS German Medical Science , 2013, DOI: 10.3205/000178
Abstract: [english] Objective: Newer non-benzodiazepines zolpidem and zopiclone are often prescribed instead of benzodiazepine hypnotics, although there is no evidence of differences in effectiveness and safety. Aim was to compare perceptions on benefits and harms of benzodiazepines and Z-drugs between general practitioners (GPs) and community pharmacists (CPs).Methods: A questionnaire was mailed to a random sample of 1,350 GPs and 600 CPs in 2012. They were asked to rate perceptions on a five-point Likert scale used for both benzodiazepines and Z-drugs. Wilcoxon signed rank test was performed for the comparison of perceptions between GPs and CPs. Due to multiple testing, only p-values ≤0.01 were considered statistically significant.Results: 458 GPs and 202 CPs returned questionnaires (response 33.9% and 33.7%). Mean age of GPs was 53.3 years (40.6% female) and 48.8 years for CPs (59.2% females). Perceptions on benefits of benzodiazepines (and Z-drugs) between GPs and CPs were not different for 3 (and 2) of 5 items. Concerning side effects of benzodiazepines, there were no statistically significant differences for 3 of 5 comparisons. CPs perceived that 4 of 5 studied side effects of Z-drugs occur significantly more often than GPs (p=0.003 or less). For instance, whereas 45.2% of CPs answered that withdrawal effects on stopping happen often or very often/always on Z-drugs, these were only 28.3% of the GPs. Conclusions: Although it is difficult to draw unambiguous conclusions from these findings, pharmacists might have a somewhat more critical view on Z-drugs, especially concerning side effects. [german] Hintergrund und Fragestellung: Die neueren Benzodiazepinrezeptor-Agonisten Zolpidem und Zopiclon (“Z-Drugs”) werden in letzter Zeit h ufiger als Hypnotika vom Benzodiazepintyp verschrieben, obwohl keine Belege für Unterschiede bezüglich des Nutzens und Schaden existieren. Ziel dieser Studie war es zu vergleichen, wie Haus rzte und Apotheker erwünschte und unerwünschte Wirkungen dieser Mittel einsch tzen.Methoden: Ein schriftlicher Fragebogen wurde 2012 an eine Zufallsauswahl von 1.350 Haus rzten und 600 Apothekenleitern versendet. Die gleichen Items wurden auf einer 5-Punkte-Likert-Skala sowohl für Benzodiazepine wie Z-Drugs abgefragt. Zum Vergleich zwischen Haus rzten und Apothekern wurden Wilcoxon Signed Rank Tests durchgeführt. Aufgrund der zahlreichen Tests wurden nur p-Werte ≤0,01 als statistisch signifikant angesehen.Ergebnisse: Insgesamt antworteten 458 Haus rzte und 202 Apotheker (Rücklauf 33,9% und 33,7%). Haus rzte waren durchschnittlich (40,6% weiblich)
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