283 research outputs found
Surrogate and reduced-order modeling: a comparison of approaches for large-scale statistical inverse problems [Chapter 7]
Solution of statistical inverse problems via the frequentist or Bayesian approaches described in earlier chapters can be a computationally intensive endeavor, particularly when faced with large-scale forward models characteristic of many engineering and science applications. High computational cost arises in several ways. First, thousands or millions of forward simulations may be required to evaluate estimators of interest or to characterize a posterior distribution. In the large-scale setting, performing so many forward simulations is often computationally intractable. Second, sampling may be complicated by the large dimensionality of the input space--as when the inputs are fields represented with spatial discretizations of high dimension--and by nonlinear forward dynamics that lead to multimodal, skewed, and/or strongly correlated posteriors. In this chapter, we present an overview of surrogate and reduced order modeling methods that address these computational challenges. For illustration, we consider a Bayesian formulation of the inverse problem. Though some of the methods we review exploit prior information, they largely focus on simplifying or accelerating evaluations of a stochastic model for the data, and thus are also applicable in a frequentist context.Sandia National Laboratories (Laboratory Directed Research and Development (LDRD) program)United States. Dept. of Energy (Contract DE-AC04-94AL85000)Singapore-MIT Alliance Computational Engineering ProgrammeUnited States. Dept. of Energy (Award Number DE-FG02-08ER25858 )United States. Dept. of Energy (Award Number DESC00025217
Design of Optimal Bonus-Malus Systems With a Frequency and a Severity Component On an Individual Basis in Automobile Insurance
Modeling Earthquake Risk via Extreme Value Theory and Pricing the Respective Catastrophe Bonds
Clinical Studies of Nonpharmacological Methods to Minimize Salivary Gland Damage after Radioiodine Therapy of Differentiated Thyroid Carcinoma: Systematic Review
Purpose. To systematically review clinical studies examining the effectiveness of nonpharmacological methods to prevent/minimize salivary gland damage due to radioiodine treatment of differentiated thyroid carcinoma (DTC). Methods. Reports on relevant trials were identified by searching the PubMed, CINHAL, Cochrane, and Scopus electronic databases covering the period 01/2000-10/2015. Inclusion/exclusion criteria were prespecified. Search yielded eight studies that were reviewed by four of the present authors. Results. Nonpharmacological methods used in trials may reduce salivary gland damage induced by radioiodine. Sialogogues such as lemon candy, vitamin E, lemon juice, and lemon slice reduced such damage significantly (p < 0.0001, p < 0.05, p < 0.10, and p < 0.05, resp.). Parotid gland massage also reduced the salivary damage significantly (p < 0.001). Additionally, vitamin C had some limited effect (p = 0.37), whereas no effect was present in the case of chewing gum(p = 0.99). Conclusion. The review showed that, among nonpharmacological interventions, sialogogues and parotid gland massage had the greatest impact on reducing salivary damage induced by radioiodine therapy of DTC. However, the studies retrieved were limited in number, sample size, strength of evidence, and generalizability. More randomized controlled trials of these methods with multicenter scope and larger sample sizes will provide more systematic and reliable results allowing more definitive conclusions
Anais.
Respostas fisiologicas de frangos de corte criados em alta densidade; Aspectos sanitarios de criacao em altas densidades; Fundamentos de ventilacao em galpoes avicolas; Desempenho e viabilidade economica da criacao de frangos de corte em alta densidade; Barreiras sanitarias na comercializacao de carnes de aves; O controle das salmonelas na cadeia produtiva avicola; Tecnicas de biologia molecular no diagnostico de doencas de aves; Falhas de vacinacao: o problema das cepas mutantes; Use of energy and water in processing plants; Commercial implementation of postmortem electrical stimulation; The influence of floock management on broiler carcass quality; Carbon dioxide stunning of poultry; Stress factors of the period prior to slaughter and effect on the microbiological quality of poultry; Poultry inspection systems and implementation of pathogen reduction program in broiler processing plants; Uso de embalagem em atmosfera modificada para carne de aves; A qualidade como instrumento gerencial na industria da carne.bitstream/item/58283/1/doc47.pd
Development of Proficiency Testing for Detection of Irradiated Food: Project E01068. Results of Second Round PSL and TL Trials, September 2006
Concurrent and Predictive Relationships Between Compulsive Internet Use and Substance Use: Findings from Vocational High School Students in China and the USA
Purpose: Compulsive Internet Use (CIU) has increasingly become an area of research among process addictions. Largely based on data from cross-sectional studies, a positive association between CIU and substance use has previously been reported. This study presents gender and country-specific longitudinal findings on the relationships between CIU and substance use. Methods: Data were drawn from youth attending non-conventional high schools, recruited into two similarly implemented trials conducted in China and the USA. The Chinese sample included 1,761 students (49% male); the US sample included 1,182 students (57% male) with over half (65%) of the US youth being of Hispanic ethnicity. Path analyses were applied to detect the concurrent and predictive relationships between baseline and one-year follow-up measures of CIU level, 30-day cigarette smoking, and 30-day binge drinking. Results: (1) CIU was not positively related with substance use at baseline. (2) There was a positive predictive relationship between baseline CIU and change in substance use among female, but not male students. (3) Relationships between concurrent changes in CIU and substance use were also found among female, but not male students. (4) Baseline substance use did not predict an increase in CIU from baseline to 1-year follow-up. Conclusions: While CIU was found to be related to substance use, the relationship was not consistently positive. More longitudinal studies with better measures for Internet Addiction are needed to ascertain the detailed relationship between Internet addiction and substance use
Essential oils as antibacterial agents against food-borne pathogens: are they really as useful as they are claimed to be ?
Original articleMost studies evaluating the use of essential oils
(EO) as antibacterial agents focus mainly on minimal
inhibitory concentrations (MIC) rather than minimal bactericidal
concentrations (MBC). In this work, we compared
MICs and MBCs of EO from condiment plants commonly
used in Mediterranean Europe, namely Origanum vulgare,
Salvia lavandulaefolia, Salvia officinalis, Salvia sclarea
and Rosmarinus officinalis, aiming to evaluate their
application as disinfecting agents in minimally processed
produce. Outbreaks-related pathogens such as Listeria
monocytogenes, Pseudomonas aeruginosa and Yarrowia
lipolytica were used. Results showed that all EO were able
to reduce bacterial growth in all bacterial strains tested,
particularly O. vulgare. However, fewer EO exhibited
bactericidal activities, and were only effective against one
or two bacterial strains, hence eliminating the possibility to
use them as broad range disinfectants. Furthermore, the
necessary concentrations were too high for food application.
Hence, our work suggests the need to evaluate MBC
rather than MIC and questions EO usefulness in controlling
undesired microorganisms. Overall, and despite the large volume of data published on EO, results obtained were not
very encouraging for a realistic application on produce and
question the viability of EOs as disinfecting agents in foodinfo:eu-repo/semantics/publishedVersio
GDF15 promotes weight loss by enhancing energy expenditure in muscle
Funding Information: We thank R. Seeley for sharing GFRAL-null mice; B. Lowell for sharing β-less mice; and J. Wu for shipping β-less mice to us. G.R.S. was supported by a Diabetes Canada Investigator Award (DI-5-17-5302-GS), a Canadian Institutes of Health Research Foundation Grant (201709FDN-CEBA-116200), a Tier 1 Canada Research Chair in Metabolic Diseases and a J. Bruce Duncan Endowed Chair in Metabolic Diseases; D.W. by Fellowship Grants from the McMaster Institute for Research on Aging (MIRA) at McMaster University; S.R. by a postdoctoral fellowship supported by MITACS and Novo Nordisk; L.K.T. by a CIHR Post-Doctoral Fellowship Award and Michael DeGroote Fellowship Award in Basic Biomedical Science; E.M.D. by a Vanier Canada Graduate Scholarship; G.P.H. by the Natural Sciences and Engineering Research Council of Canada (NSERC: 400362); G.J.D. and S.M.F. by NSERC-CGSM scholarships; L.D. by the Fonds de Recherche du Québec-Santé doctoral training award; D.P.B. by the GSK Chair in Diabetes of Université de Sherbrooke and a FRQS J1 salary award. The Genotype-Tissue Expression (GTEx) Project was supported by the Common Fund of the Office of the Director of the National Institutes of Health, and by the NCI, NHGRI, NHLBI, NIDA, NIMH and NINDS. Funding Information: S.B.J. and R.E.K. are employees of Novo Nordisk, a pharmaceutical company producing and selling medicine for the treatment of diabetes and obesity. G.R.S. is a co-founder and shareholder of Espervita Therapeutics. McMaster University has received funding from Espervita Therapeutics, Esperion Therapeutics, Poxel Pharmaceuticals and Nestle for research conducted in the laboratory of G.R.S. S.R. is supported by a MITACS postdoctoral fellowship sponsored by Novo Nordisk. H.C.G. holds the McMaster-Sanofi Population Health Institute Chair in Diabetes Research and Care. G.R.S., G.P. and H.C.G. are inventors listed on a patent for identifying GDF15 as a biomarker for metformin. G.R.S. has received consulting/speaking fees from Astra Zeneca, Eli Lilly, Esperion Therapeutics, Merck, Poxel Pharmaceuticals and Cambrian Biosciences. The other authors declare no competing interests. Publisher Copyright: © 2023, The Author(s).Peer reviewedPublisher PD
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