Identifying patterns of motor performance, executive functioning, and verbal ability in preschool children: A latent profile analysis.

Science.gov (United States)

Houwen, Suzanne; Kamphorst, Erica; van der Veer, Gerda; Cantell, Marja

2018-04-30

A relationship between motor performance and cognitive functioning is increasingly being recognized. Yet, little is known about the precise nature of the relationship between both domains, especially in early childhood. To identify distinct constellations of motor performance, executive functioning (EF), and verbal ability in preschool aged children; and to explore how individual and contextual variables are related to profile membership. The sample consisted of 119 3- to 4-year old children (62 boys; 52%). The home based assessments consisted of a standardized motor test (Movement Assessment Battery for Children - 2), five performance-based EF tasks measuring inhibition and working memory, and the Receptive Vocabulary subtest from the Wechsler Preschool and Primary Scale of Intelligence Third Edition. Parents filled out the Behavior Rating Inventory of Executive Function - Preschool version. Latent profile analysis (LPA) was used to delineate profiles of motor performance, EF, and verbal ability. Chi-square statistics and multinomial logistic regression analysis were used to examine whether profile membership was predicted by age, gender, risk of motor coordination difficulties, ADHD symptomatology, language problems, and socioeconomic status (SES). LPA yielded three profiles with qualitatively distinct response patterns of motor performance, EF, and verbal ability. Quantitatively, the profiles showed most pronounced differences with regard to parent ratings and performance-based tests of EF, as well as verbal ability. Risk of motor coordination difficulties and ADHD symptomatology were associated with profile membership, whereas age, gender, language problems, and SES were not. Our results indicate that there are distinct subpopulations of children who show differential relations with regard to motor performance, EF, and verbal ability. The fact that we found both quantitative as well as qualitative differences between the three patterns of profiles underscores

Brownfields/IGD: EF_ACRES

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U.S. Environmental Protection Agency — EF_ACRES is a subset of facilities from FRS_INTEREST and FRS_FACILITY_SITE which are updated on a monthly basis as part of the Locational Reference Tables (LRT)...

Superfund/IGD: EF_NPL

Data.gov (United States)

U.S. Environmental Protection Agency — EF_NPL is a subset of facilities from FRS_INTEREST and FRS_FACILITY_SITE which are updated on a monthly basis as part of the Locational Reference Tables (LRT)...

A developmental study of latent absolute pitch memory.

Science.gov (United States)

Jakubowski, Kelly; Müllensiefen, Daniel; Stewart, Lauren

2017-03-01

The ability to recall the absolute pitch level of familiar music (latent absolute pitch memory) is widespread in adults, in contrast to the rare ability to label single pitches without a reference tone (overt absolute pitch memory). The present research investigated the developmental profile of latent absolute pitch (AP) memory and explored individual differences related to this ability. In two experiments, 288 children from 4 to12 years of age performed significantly above chance at recognizing the absolute pitch level of familiar melodies. No age-related improvement or decline, nor effects of musical training, gender, or familiarity with the stimuli were found in regard to latent AP task performance. These findings suggest that latent AP memory is a stable ability that is developed from as early as age 4 and persists into adulthood.

75 FR 27986 - Electronic Filing System-Web (EFS-Web) Contingency Option

Science.gov (United States)

2010-05-19

...] Electronic Filing System--Web (EFS-Web) Contingency Option AGENCY: United States Patent and Trademark Office... contingency option when the primary portal to EFS-Web has an unscheduled outage. Previously, the entire EFS-Web system is not available to the users during such an outage. The contingency option in EFS-Web will...

poLCA: An R Package for Polytomous Variable Latent Class Analysis

Directory of Open Access Journals (Sweden)

Drew A. Linzer

2011-08-01

Full Text Available poLCA is a software package for the estimation of latent class and latent class regression models for polytomous outcome variables, implemented in the R statistical computing environment. Both models can be called using a single simple command line. The basic latent class model is a finite mixture model in which the component distributions are assumed to be multi-way cross-classification tables with all variables mutually independent. The latent class regression model further enables the researcher to estimate the effects of covariates on predicting latent class membership. poLCA uses expectation-maximization and Newton-Raphson algorithms to find maximum likelihood estimates of the model parameters.

Simultaneous Binding of Multiple EF-Tu Copies to Translating Ribosomes in Live Escherichia coli.

Science.gov (United States)

Mustafi, Mainak; Weisshaar, James C

2018-01-16

In bacteria, elongation factor Tu is a translational cofactor that forms ternary complexes with aminoacyl-tRNA (aa-tRNA) and GTP. Binding of a ternary complex to one of four flexible L7/L12 units on the ribosome tethers a charged tRNA in close proximity to the ribosomal A site. Two sequential tests for a match between the aa-tRNA anticodon and the current mRNA codon then follow. Because one elongation cycle can occur in as little as 50 ms and the vast majority of aa-tRNA copies are not cognate with the current mRNA codon, this testing must occur rapidly. We present a single-molecule localization and tracking study of fluorescently labeled EF-Tu in live Escherichia coli Imaging at 2 ms/frame distinguishes 60% slowly diffusing EF-Tu copies (assigned as transiently bound to translating ribosome) from 40% rapidly diffusing copies (assigned as a mixture of free ternary complexes and free EF-Tu). Combining these percentages with copy number estimates, we infer that the four L7/L12 sites are essentially saturated with ternary complexes in vivo. The results corroborate an earlier inference that all four sites can simultaneously tether ternary complexes near the A site, creating a high local concentration that may greatly enhance the rate of testing of aa-tRNAs. Our data and a combinatorial argument both suggest that the initial recognition test for a codon-anticodon match occurs in less than 1 to 2 ms per aa-tRNA copy. The results refute a recent study (A. Plochowietz, I. Farrell, Z. Smilansky, B. S. Cooperman, and A. N. Kapanidis, Nucleic Acids Res 45:926-937, 2016, https://doi.org/10.1093/nar/gkw787) of tRNA diffusion in E. coli that inferred that aa-tRNAs arrive at the ribosomal A site as bare monomers, not as ternary complexes. IMPORTANCE Ribosomes catalyze translation of the mRNA codon sequence into the corresponding sequence of amino acids within the nascent polypeptide chain. Polypeptide elongation can be as fast as 50 ms per added amino acid. Each amino acid

Predictors and Prognostic Value of Worsening Renal Function During Admission in HFpEF Versus HFrEF: Data From the KorAHF (Korean Acute Heart Failure) Registry.

Science.gov (United States)

Kang, Jeehoon; Park, Jin Joo; Cho, Young-Jin; Oh, Il-Young; Park, Hyun-Ah; Lee, Sang Eun; Kim, Min-Seok; Cho, Hyun-Jai; Lee, Hae-Young; Choi, Jin Oh; Hwang, Kyung-Kuk; Kim, Kye Hun; Yoo, Byung-Su; Kang, Seok-Min; Baek, Sang Hong; Jeon, Eun-Seok; Kim, Jae-Joong; Cho, Myeong-Chan; Chae, Shung Chull; Oh, Byung-Hee; Choi, Dong-Ju

2018-03-13

Worsening renal function (WRF) is associated with adverse outcomes in patients with heart failure. We investigated the predictors and prognostic value of WRF during admission, in patients with preserved ejection fraction (HFpEF) versus those with reduced ejection fraction (HFrEF). A total of 5625 patients were enrolled in the KorAHF (Korean Acute Heart Failure) registry. WRF was defined as an absolute increase in creatinine of ≥0.3 mg/dL. Transient WRF was defined as recovery of creatinine at discharge, whereas persistent WRF was indicated by a nonrecovered creatinine level. HFpEF and HFrEF were defined as a left ventricle ejection fraction ≥50% and ≤40%, respectively. Among the total population, WRF occurred in 3101 patients (55.1%). By heart failure subgroup, WRF occurred more frequently in HFrEF (57.0% versus 51.3%; P failure subgroups. Among various predictors of WRF, chronic renal failure was the strongest predictor. WRF was an independent predictor of adverse in-hospital outcomes (HFrEF: odds ratio; 2.75; 95% confidence interval, 1.50-5.02; P =0.001; HFpEF: odds ratio, 9.48; 95% confidence interval, 1.19-75.89; P =0.034) and 1-year mortality (HFrEF: hazard ratio, 1.41; 95% confidence interval, 1.12-1.78; P =0.004 versus HFpEF: hazard ratio, 1.72; 95% confidence interval, 1.23-2.42; P =0.002). Transient WRF was a risk factor for 1-year mortality, whereas persistent WRF had no additive risk compared to transient WRF. In patients with acute heart failure patients, WRF is an independent predictor of adverse in-hospital and follow-up outcomes in both HFrEF and HFpEF, though with a different effect size. URL: https://www.clinicaltrials.gov. Unique identifier: NCT01389843. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Pathophysiological understanding of HFpEF: microRNAs as part of the puzzle.

Science.gov (United States)

Rech, Monika; Barandiarán Aizpurua, Arantxa; van Empel, Vanessa; van Bilsen, Marc; Schroen, Blanche

2018-05-01

Half of all heart failure patients have preserved ejection fraction (HFpEF). Comorbidities associated with and contributing to HFpEF include obesity, diabetes and hypertension. Still, the underlying pathophysiological mechanisms of HFpEF are unknown. A preliminary consensus proposes that the multi-morbidity triggers a state of systemic, chronic low-grade inflammation, and microvascular dysfunction, causing reduced nitric oxide bioavailability to adjacent cardiomyocytes. As a result, the cardiomyocyte remodels its contractile elements and fails to relax properly, causing diastolic dysfunction, and eventually HFpEF. HFpEF is a complex syndrome for which currently no efficient therapies exist. This is notably due to the current one-size-fits-all therapy approach that ignores individual patient differences. MicroRNAs have been studied in relation to pathophysiological mechanisms and comorbidities underlying and contributing to HFpEF. As regulators of gene expression, microRNAs may contribute to the pathophysiology of HFpEF. In addition, secreted circulating microRNAs are potential biomarkers and as such, they could help stratify the HFpEF population and open new ways for individualized therapies. In this review, we provide an overview of the ever-expanding world of non-coding RNAs and their contribution to the molecular mechanisms underlying HFpEF. We propose prospects for microRNAs in stratifying the HFpEF population. MicroRNAs add a new level of complexity to the regulatory network controlling cardiac function and hence the understanding of gene regulation becomes a fundamental piece in solving the HFpEF puzzle.

A Review of the Latent and Manifest Benefits (LAMB) Scale

Science.gov (United States)

Muller, Juanita; Waters, Lea

2012-01-01

The latent and manifest benefits (LAMB) scale (Muller, Creed, Waters & Machin, 2005) was designed to measure the latent and manifest benefits of employment and provide a single scale to test Jahoda's (1981) and Fryer's (1986) theories of unemployment. Since its publication in 2005 there have been 13 studies that have used the scale with 5692…

Contrast in atomically resolved EF-SCEM imaging

Energy Technology Data Exchange (ETDEWEB)

Wang, Peng [National Laboratory of Solid State Microstructures and Department of Materials Science and Engineering, Nanjing University, Nanjing 210093 (China); D’Alfonso, Adrian J. [School of Physics, University of Melbourne, Parkville, Victoria 3010 (Australia); Hashimoto, Ayako [Surface Physics and Structure Unit, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047 (Japan); Global Research Center for Environment and Energy based on Nanomaterials Science, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, 305-0047 (Japan); Electron Microscopy Station, National Institute for Materials Science, 3-13 Sakura, Tsukuba 305-0003 (Japan); Morgan, Andrew J. [School of Physics, University of Melbourne, Parkville, Victoria 3010 (Australia); Takeguchi, Masaki [Surface Physics and Structure Unit, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047 (Japan); Electron Microscopy Station, National Institute for Materials Science, 3-13 Sakura, Tsukuba 305-0003 (Japan); Mitsuishi, Kazutaka [Surface Physics and Structure Unit, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047 (Japan); Global Research Center for Environment and Energy based on Nanomaterials Science, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, 305-0047 (Japan); Electron Microscopy Station, National Institute for Materials Science, 3-13 Sakura, Tsukuba 305-0003 (Japan); Shimojo, Masayuki [Department of Materials Science and Engineering, Shibaura Institute of Technology, 3-7-5, Toyosu, Koto-ku, Tokyo, 135-8548 (Japan); Kirkland, Angus I. [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Allen, Leslie J. [School of Physics, University of Melbourne, Parkville, Victoria 3010 (Australia); Nellist, Peter D., E-mail: peter.nellist@materials.ox.ac.uk [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom)

2013-11-15

Energy-filtered scanning confocal electron microscopy (EF-SCEM) is a technique that uses the reduced depth of field of an aberration-corrected transmission electron microscope to provide three-dimensional (3D) compositional information. Using a silicon sample in the <110> orientation, we show that EF-SCEM image data can be recorded that shows lattice resolution in the plane perpendicular to the incident beam direction. The confocal effect is demonstrated through the reduction of the mean intensity as the confocal plane is displaced from the sample mid-plane, unlike optical sectioning in high-angle annular dark-field scanning transmission electron microscopy (STEM). Simulations of the EF-SCEM data show agreement with the experimental data, and allow the interpretability of the data to be explored. The effects of channelling, absorption and delocalisation complicate the quantitative and qualitative interpretation of the data, highlighting the need for matching to simulations. Finally the effects of the finite detector pin-hole aperture size are explored, and we show that the EF-SCEM contrast in the plane perpendicular to the beam direction starts to resemble that of a STEM spectrum imaging experiment as the aperture size increases. - Highlights: • Atomically resolved energy-filtered scanning confocal electron microscopy (EF-SCEM) is demonstrated. • The confocal effect is demonstrated through the reduction of the mean intensity as the confocal plane is displaced from the sample mid-plane. • Simulations show agreement with the experimental data. • The effects of channelling, absorption and delocalisation complicate the quantitative and qualitative interpretation of the data. • The effects of the finite detector pin-hole aperture size are explored.

Contrast in atomically resolved EF-SCEM imaging

International Nuclear Information System (INIS)

Wang, Peng; D’Alfonso, Adrian J.; Hashimoto, Ayako; Morgan, Andrew J.; Takeguchi, Masaki; Mitsuishi, Kazutaka; Shimojo, Masayuki; Kirkland, Angus I.; Allen, Leslie J.; Nellist, Peter D.

2013-01-01

Energy-filtered scanning confocal electron microscopy (EF-SCEM) is a technique that uses the reduced depth of field of an aberration-corrected transmission electron microscope to provide three-dimensional (3D) compositional information. Using a silicon sample in the orientation, we show that EF-SCEM image data can be recorded that shows lattice resolution in the plane perpendicular to the incident beam direction. The confocal effect is demonstrated through the reduction of the mean intensity as the confocal plane is displaced from the sample mid-plane, unlike optical sectioning in high-angle annular dark-field scanning transmission electron microscopy (STEM). Simulations of the EF-SCEM data show agreement with the experimental data, and allow the interpretability of the data to be explored. The effects of channelling, absorption and delocalisation complicate the quantitative and qualitative interpretation of the data, highlighting the need for matching to simulations. Finally the effects of the finite detector pin-hole aperture size are explored, and we show that the EF-SCEM contrast in the plane perpendicular to the beam direction starts to resemble that of a STEM spectrum imaging experiment as the aperture size increases. - Highlights: • Atomically resolved energy-filtered scanning confocal electron microscopy (EF-SCEM) is demonstrated. • The confocal effect is demonstrated through the reduction of the mean intensity as the confocal plane is displaced from the sample mid-plane. • Simulations show agreement with the experimental data. • The effects of channelling, absorption and delocalisation complicate the quantitative and qualitative interpretation of the data. • The effects of the finite detector pin-hole aperture size are explored

Roles of Protein Synthesis Elongation Factor EF-Tu in Heat Tolerance in Plants

Directory of Open Access Journals (Sweden)

Jianming Fu

2012-01-01

Full Text Available EF-Tu proteins of plastids, mitochondria, and the cytosolic counterpart EF-1α in plants, as well as EF-Tu proteins of bacteria, are highly conserved and multifunctional. The functions of EF-Tu include transporting the aminoacyl-tRNA complex to the A site of the ribosome during protein biosynthesis; chaperone activity in protecting other proteins from aggregation caused by environmental stresses, facilitating renaturation of proteins when conditions return to normal; displaying a protein disulfide isomerase activity; participating in the degradation of N-terminally blocked proteins by the proteasome; eliciting innate immunity and triggering resistance to pathogenic bacteria in plants; participating in transcription when an E. coli host is infected with phages. EF-Tu genes are upregulated by abiotic stresses in plants, and EF-Tu plays important role in stress responses. Expression of a plant EF-Tu gene confers heat tolerance in E. coli, maize knock-out EF-Tu null mutants are heat susceptible, and over-expression of an EF-Tu gene improves heat tolerance in crop plants. This review paper summarizes the current knowledge of EF-Tu proteins in stress responses in plants and progress on application of EF-Tu for developing crop varieties tolerant to abiotic stresses, such as high temperatures.

Hazardous Waste/IGD: EF_RCRA

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U.S. Environmental Protection Agency — EF_RCRA is a subset of facilities from FRS_INTEREST and FRS_FACILITY_SITE which are updated on a monthly basis as part of the Locational Reference Tables (LRT)...

Air Emissions/IGD: EF_AFS

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U.S. Environmental Protection Agency — EF_AFS is a subset of facilities from FRS_INTEREST and FRS_FACILITY_SITE which are updated on a monthly basis as part of the Locational Reference Tables (LRT)...

Water Dischargers/IGD: EF_NPDES

Data.gov (United States)

U.S. Environmental Protection Agency — EF_NPDES is a subset of facilities from FRS_INTEREST and FRS_FACILITY_SITE which are updated on a monthly basis as part of the Locational Reference Tables (LRT)...

Toxic Releases/IGD: EF_TRI

Data.gov (United States)

U.S. Environmental Protection Agency — EF_TRI is a subset of facilities from FRS_INTEREST and FRS_FACILITY_SITE which are updated on a monthly basis as part of the Locational Reference Tables (LRT)...

Labeled EF-Tus for rapid kinetic studies of pretranslocation complex formation

DEFF Research Database (Denmark)

Liu, Wei; Kavaliauskas, Darius; Schrader, Jared

2014-01-01

The universally conserved translation elongation factor EF-Tu delivers aminoacyl(aa)-tRNA in the form of an aa-tRNA·EF-Tu·GTP ternary complex (TC) to the ribosome where it binds to the cognate mRNA codon within the ribosomal A-site, leading to formation of a pretranslocation (PRE) complex. Here we...... describe preparation of QSY9 and Cy5 derivatives of the variant E348C-EF-Tu that are functional in translation elongation. Together with fluorophore derivatives of aa-tRNA and of ribosomal protein L11, located within the GTPase associated center (GAC), these labeled EF-Tus allow development of two new FRET...... assays that permit the dynamics of distance changes between EF-Tu and both L11 (Tu-L11 assay) and aa-tRNA (Tu-tRNA assay) to be determined during the decoding process. We use these assays to examine: (i) the relative rates of EF-Tu movement away from the GAC and from aa-tRNA during decoding, (ii...

Stability of alcohol use and teen dating violence for female youth: A latent transition analysis.

Science.gov (United States)

Choi, Hye Jeong; Elmquist, JoAnna; Shorey, Ryan C; Rothman, Emily F; Stuart, Gregory L; Temple, Jeff R

2017-01-01

Alcohol use is one of the most widely accepted and studied risk factors for teen dating violence (TDV). Too little research has explored longitudinally if it is true that an adolescent's alcohol use and TDV involvement simultaneously occur. In the current study, we examined whether there were latent status based on past-year TDV and alcohol use and whether female adolescents changed their statuses of TDV and alcohol use over time. The sample consisted of 583 female youths in seven public high schools in Texas. Three waves of longitudinal data collected from 2011 to 2013 were utilised in this study. Participants completed self-report assessments of alcohol use (past-year alcohol use, number of drinks in the past month and episodic heavy drinking within the past month) and psychological and physical TDV victimisation and perpetration. Latent transition analysis was used to examine if the latent status based on TDV and alcohol use changed over time. Five separate latent statuses were identified: (i) no violence, no alcohol; (ii) alcohol; (iii) psychological violence, no alcohol; (iv) psychological violence, alcohol; and (v) physical and psychological violence, alcohol. Latent transition analysis indicated that adolescents generally remained in the same subgroup across time. This study provides evidence on the co-occurrence of alcohol use and teen dating violence, and whether teens' status based on dating violence and alcohol use are stable over time. Findings from the current study highlight the importance of targeting both TDV and substance use in intervention and prevention programs. [Choi HJ, Elmquist J, Shorey RC, Rothman EF, Stuart GL,Temple JR. Stability of alcohol use and teen dating violence for female youth: Alatent transition analysis. Drug Alcohol Rev 2017;36:80-87]. © 2017 Australasian Professional Society on Alcohol and other Drugs.

Estimating Daily Evapotranspiration Based on A Model of Evapotranspiration Fraction (EF) for Mixed Pixels

Science.gov (United States)

Xin, X.; Li, F.; Peng, Z.; Qinhuo, L.

2017-12-01

Land surface heterogeneities significantly affect the reliability and accuracy of remotely sensed evapotranspiration (ET), and it gets worse for lower resolution data. At the same time, temporal scale extrapolation of the instantaneous latent heat flux (LE) at satellite overpass time to daily ET are crucial for applications of such remote sensing product. The purpose of this paper is to propose a simple but efficient model for estimating daytime evapotranspiration considering heterogeneity of mixed pixels. In order to do so, an equation to calculate evapotranspiration fraction (EF) of mixed pixels was derived based on two key assumptions. Assumption 1: the available energy (AE) of each sub-pixel equals approximately to that of any other sub-pixels in the same mixed pixel within acceptable margin of bias, and as same as the AE of the mixed pixel. It's only for a simpification of the equation, and its uncertainties and resulted errors in estimated ET are very small. Assumption 2: EF of each sub-pixel equals to the EF of the nearest pure pixel(s) of same land cover type. This equation is supposed to be capable of correcting the spatial scale error of the mixed pixels EF and can be used to calculated daily ET with daily AE data.The model was applied to an artificial oasis in the midstream of Heihe River. HJ-1B satellite data were used to estimate the lumped fluxes at the scale of 300 m after resampling the 30-m resolution datasets to 300 m resolution, which was used to carry on the key step of the model. The results before and after correction were compare to each other and validated using site data of eddy-correlation systems. Results indicated that the new model is capable of improving accuracy of daily ET estimation relative to the lumped method. Validations at 12 sites of eddy-correlation systems for 9 days of HJ-1B overpass showed that the R² increased to 0.82 from 0.62; the RMSE decreased to 1.60 MJ/m² from 2.47MJ/m²; the MBE decreased from 1.92 MJ/m² to 1

Contribution of effluent organic matter (EfOM) to ultrafiltration (UF) membrane fouling: Isolation, characterization, and fouling effect of EfOM fractions

KAUST Repository

Zheng, Xing

2014-11-01

EfOM has been regarded as a major organic foulant resulting in UF membrane fouling in wastewater reclamation. To investigate fouling potential of different EfOM fractions, the present study isolated EfOM into hydrophobic neutrals (HPO-N), colloids, hydrophobic acids (HPO-A), transphilic neutrals and acids (TPI), and hydrophilics (HPI), and tested their fouling effect in both salt solution and pure water during ultrafiltration (UF). Major functional groups and chemical structure of the isolates were identified using Fourier transform infrared spectroscopy (FT-IR) and solid-state carbon nuclear magnetic resonance (13C NMR) analysis. The influence of the isolation process on the properties of EfOM fractions was minor because the raw and reconstituted secondary effluents were found similar with respect to UV absorbance, molecular size distribution, and fluorescence character. In membrane filtration tests, unified membrane fouling index (UMFI) and hydraulic resistance were used to quantify irreversible fouling potential of different water samples. Results show that under similar DOC level in feed water, colloids present much more irreversible fouling than other fractions. The fouling effect of the isolates is related to their size, chemical properties, and solution chemistry. Further investigations have identified that the interaction between colloids and other fractions also influences the performance of colloids in fouling phenomena. © 2014 Elsevier Ltd.

Electrostatics effects on Ca(2+) binding and conformational changes in EF-hand domains: Functional implications for EF-hand proteins.

Science.gov (United States)

Ababou, Abdessamad; Zaleska, Mariola

2015-12-01

Mutations of Gln41 and Lys75 with nonpolar residues in the N-terminal domain of calmodulin (N-Cam) revealed the importance of solvation energetics in conformational change of Ca(2+) sensor EF-hand domains. While in general these domains have polar residues at these corresponding positions yet the extent of their conformational response to Ca(2+) binding and their Ca(2+) binding affinity can be different from N-Cam. Consequently, here we address the charge state of the polar residues at these positions. The results show that the charge state of these polar residues can affect substantially the conformational change and the Ca(2+) binding affinity of our N-Cam variants. Since all the variants kept their conformational activity in the presence of Ca(2+) suggests that the differences observed among them mainly originate from the difference in their molecular dynamics. Hence we propose that the molecular dynamics of Ca(2+) sensor EF-hand domains is a key factor in the multifunctional aspect of EF-hand proteins. Copyright © 2015 Elsevier Inc. All rights reserved.

Latent heat coldness storage; Stockage du froid par chaleur latente

Energy Technology Data Exchange (ETDEWEB)

Dumas, J.P. [Pau Univ., Lab. de Thermodynamique et Energetique, LTE, 64 (France)

2002-07-01

This article presents the advantages of latent heat storage systems which use the solid-liquid phase transformation of a pure substance or of a solution. The three main methods of latent heat storage of coldness are presented: ice boxes, encapsulated nodules, and ice flows: 1 - definition of the thermal energy storage (sensible heat, latent heat, thermochemical storage); 2 - advantages and drawbacks of latent heat storage; 3 - choice criteria for a phase-change material; 4 - phenomenological aspect of liquid-solid transformations (phase equilibrium, crystallisation and surfusion); 5 - different latent heat storage processes (ice boxes, encapsulated nodules, two-phase refrigerating fluids); 6 - ice boxes (internal and external melting, loop, air injection, measurement of ice thickness); 7 - encapsulated nodules (nodules, tank, drainage, advantage and drawbacks, charge and discharge); 8 - two-phase refrigerating fluids (composition, ice fabrication, flow circulation, flow storage, exchangers). (J.S.)

Latent palmprint matching.

Science.gov (United States)

Jain, Anil K; Feng, Jianjiang

2009-06-01

The evidential value of palmprints in forensic applications is clear as about 30 percent of the latents recovered from crime scenes are from palms. While biometric systems for palmprint-based personal authentication in access control type of applications have been developed, they mostly deal with low-resolution (about 100 ppi) palmprints and only perform full-to-full palmprint matching. We propose a latent-to-full palmprint matching system that is needed in forensic applications. Our system deals with palmprints captured at 500 ppi (the current standard in forensic applications) or higher resolution and uses minutiae as features to be compatible with the methodology used by latent experts. Latent palmprint matching is a challenging problem because latent prints lifted at crime scenes are of poor image quality, cover only a small area of the palm, and have a complex background. Other difficulties include a large number of minutiae in full prints (about 10 times as many as fingerprints), and the presence of many creases in latents and full prints. A robust algorithm to reliably estimate the local ridge direction and frequency in palmprints is developed. This facilitates the extraction of ridge and minutiae features even in poor quality palmprints. A fixed-length minutia descriptor, MinutiaCode, is utilized to capture distinctive information around each minutia and an alignment-based minutiae matching algorithm is used to match two palmprints. Two sets of partial palmprints (150 live-scan partial palmprints and 100 latent palmprints) are matched to a background database of 10,200 full palmprints to test the proposed system. Despite the inherent difficulty of latent-to-full palmprint matching, rank-1 recognition rates of 78.7 and 69 percent, respectively, were achieved in searching live-scan partial palmprints and latent palmprints against the background database.

Sordarin derivatives induce a novel conformation of the yeast ribosome translocation factor eEF2

DEFF Research Database (Denmark)

Søe, Rikke; Mosley, R.T.; Justice, M.

2007-01-01

EF2 that form the ligand binding pocket are oriented in a different manner relative to the rest of eEF2 compared to our previous structure of eEF2 in complex with the parent natural product sordarin. Yeast eEF2 is also shown to bind adenylic nucleotides, which can be displaced by sordarin, suggesting...... that ADP or ATP also bind to the three C-terminal domains of eEF2. Fusidic acid is a universal inhibitor of translation that targets EF-G or eEF2, and is widely used as an antibiotic against gram positive bacteria. Based on mutations conferring resistance to fusidic acid, cryo-EM reconstructions, and X...

Mapping the human translation elongation factor eEF1H complex using the yeast two-hybrid system

DEFF Research Database (Denmark)

Mansilla, Francisco; Friis, Irene; Jadidi, Mandana

2002-01-01

In eukaryotes, the eukaryotic translation elongation factor eEF1A responsible for transporting amino-acylated tRNA to the ribosome forms a higher-order complex, eEF1H, with its guanine-nucleotide-exchange factor eEF1B. In metazoans, eEF1B consists of three subunits: eEF1B alpha, eEF1B eta and eEF1B...... of in vitro experiments have been proposed for the macromolecular organization of the eEF1H complex. However, these models differ in various aspects. This might be due to the difficulties of handling, particularly the eEF1B beta and eEF1B gamma subunits in vitro. Here, the human eEF1H complex is for the first...... gamma:eEF1B beta, where the last was observed using a three-hybrid approach. Surprisingly, eEF1A2 showed no or only little affinity for the guanine-nucleotide-exchange factors. Truncated versions of the subunits of eEF1B were used to orientate these subunits within the resulting model. The model unit...

What the CERAD Battery Can Tell Us about Executive Function as a Higher-Order Cognitive Faculty

Directory of Open Access Journals (Sweden)

Rochelle E. Tractenberg

2010-01-01

Full Text Available Executive function (EF is believed to control or influence the integration and application of cognitive functions such as attention and memory and is an important area of research in cognitive aging. Recent studies and reviews have concluded that there is no single test for EF. Results from first-order latent variable modeling have suggested that little, if any, variability in cognitive performance can be directly (and uniquely attributed to EF; so instead, we modeled EF, as it is conceptualized, as a higher-order function, using elements of the CERAD neuropsychological battery. Responses to subtests from two large, independent cohorts of nondemented elderly persons were modeled with three theoretically plausible structural models using confirmatory factor analysis. Robust fit statistics, generated for the two cohorts separately, were consistent and support the conceptualization of EF as a higher-order cognitive faculty. Although not specifically designed to assess EF, subtests of the CERAD battery provide theoretically and empirically robust evidence about the nature of EF in elderly adults.

The eEF1A proteins: at the crossroads of oncogenesis, apoptosis and viral infections.

Directory of Open Access Journals (Sweden)

Georges eHerbein

2015-04-01

Full Text Available Eukaryotic translation elongation factors 1 alpha, eEF1A1 and eEF1A2, are not only translation factors, but also pleiotropic proteins that are highly expressed in human tumors, including breast cancer, ovarian cancer and lung cancer. eEF1A1 modulates cytoskeleton, exhibits chaperone-like activity and also controls cell proliferation and cell death. By contrast eEF1A2 protein favors oncogenesis as shown by the fact that overexpression of eEF1A2 leads to cellular transformation and gives rise to tumors in nude mice. The eEF1A2 protein stimulates the phospholipid signaling and activates the Akt-dependent cell migration and actin remodeling that ultimately favors tumorigenesis. By contrast, inactivation of eEF1A proteins leads to immunodeficiency, neural and muscular defects, and favors apoptosis. Finally, eEF1A proteins interact with several viral proteins resulting in enhanced viral replication, decreased apoptosis and increased cellular transformation. This review summarizes the recent findings on eEF1A proteins indicating that eEF1A proteins play a critical role in numerous human diseases through enhancement of oncogenesis, blockade of apoptosis and increased viral pathogenesis.

Bacterial translation elongation factor EF-Tu interacts and colocalizes with actin-like MreB protein.

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Defeu Soufo, Hervé Joël; Reimold, Christian; Linne, Uwe; Knust, Tobias; Gescher, Johannes; Graumann, Peter L

2010-02-16

We show that translation initiation factor EF-Tu plays a second important role in cell shape maintenance in the bacterium Bacillus subtilis. EF-Tu localizes in a helical pattern underneath the cell membrane and colocalizes with MreB, an actin-like cytoskeletal element setting up rod cell shape. The localization of MreB and of EF-Tu is interdependent, but in contrast to the dynamic MreB filaments, EF-Tu structures are more static and may serve as tracks for MreB filaments. In agreement with this idea, EF-Tu and MreB interact in vivo and in vitro. Lowering of the EF-Tu levels had a minor effect on translation but a strong effect on cell shape and on the localization of MreB, and blocking of the function of EF-Tu in translation did not interfere with the localization of MreB, showing that, directly or indirectly, EF-Tu affects the cytoskeletal MreB structure and thus serves two important functions in a bacterium.

The eukaryotic translation elongation factor eEF1A2 induces neoplastic properties and mediates tumorigenic effects of ZNF217 in precursor cells of human ovarian carcinomas

Energy Technology Data Exchange (ETDEWEB)

Sun, Yu; Wong, Nicholas; Guan, Yinghui; Salamanca, Clara M.; Cheng, Jung Chien; Lee, Jonathan M.; Gray, Joe W.; Auersperg, Nelly

2008-04-25

Ovarian epithelial carcinomas (OEC) frequently exhibit amplifications at the 20q13 locus which is the site of several oncogenes, including the eukaryotic elongation factor EEF1A2 and the transcription factor ZNF217. We reported previously that overexpressed ZNF217 induces neoplastic characteristics in precursor cells of OEC. Unexpectedly, ZNF217, which is a transcriptional repressor, enhanced expression of eEF1A2. In this study, array comparative genomic hybridization, single nucleotide polymorphism and Affymetrix analysis of ZNF217-overexpressing cell lines confirmed consistently increased expression of eEF1A2 but not of other oncogenes, and revealed early changes in EEF1A2 gene copy numbers and increased expression at crisis during immortalization. We defined the influence of eEF1A2 overexpression on immortalized ovarian surface epithelial cells, and investigated interrelationships between effects of ZNF217 and eEF1A2 on cellular phenotypes. Lentivirally induced eEF1A2 overexpression caused delayed crisis, apoptosis resistance and increases in serum-independence, saturation densities, and anchorage independence. siRNA to eEF1A2 reversed apoptosis resistance and reduced anchorage independence in eEF1A2-overexpressing lines. Remarkably, siRNA to eEF1A2 was equally efficient in inhibiting both anchorage independence and resistance to apoptosis conferred by ZNF217 overexpression. Our data define neoplastic properties that are caused by eEF1A2 in nontumorigenic ovarian cancer precursor cells, and suggest that eEF1A2 plays a role in mediating ZNF217-induced neoplastic progression.

Murine elongation factor 1 alpha (EF-1 alpha) is posttranslationally modified by novel amide-linked ethanolamine-phosphoglycerol moieties. Addition of ethanolamine-phosphoglycerol to specific glutamic acid residues on EF-1 alpha

International Nuclear Information System (INIS)

Whiteheart, S.W.; Shenbagamurthi, P.; Chen, L.; Cotter, R.J.; Hart, G.W.

1989-01-01

Elongation Factor 1 alpha (EF-1 alpha), an important eukaryotic translation factor, transports charged aminoacyl-tRNA from the cytosol to the ribosomes during poly-peptide synthesis. Metabolic radiolabeling with [ 3 H] ethanolamine shows that, in all cells examined, EF-1 alpha is the major radiolabeled protein. Radiolabeled EF-1 alpha has an apparent Mr = 53,000 and a basic isoelectric point. It is cytosolic and does not contain N-linked oligosaccharides. Trypsin digestion of murine EF-1 alpha generated two major [ 3 H]ethanolamine-labeled peptides. Three peptides were sequenced and were identical to two distinct regions of the human EF-1 alpha protein. Blank sequencing cycles coinciding with glutamic acid in the human cDNA-derived sequence were also found to release [ 3 H]ethanolamine, and compositional analysis of these peptides confirmed the presence of glutamic acid. Dansylation analysis demonstrates that the amine group of the ethanolamine is blocked. These results indicate that EF-1 alpha is posttranslationally modified by the covalent attachment of ethanolamine via an amide bond to at least two specific glutamic acid residues (Glu-301 and Glu-374). The hydroxyl group of the attached ethanolamine was shown by mass spectrometry and compositional analysis, to be further modified by the addition of a phosphoglycerol unit. This novel posttranslational modification may represent an important alteration of EF-1 alpha, comparable to the regulatory effects of posttranslational methylation of EF-1 alpha lysine residues

Heat-Killed Enterococcus faecalis EF-2001 Ameliorates Atopic Dermatitis in a Murine Model

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Choi, Eun-Ju; Iwasa, Masahiro; Han, Kwon-Il; Kim, Wan-Jae; Tang, Yujiao; Hwang, Young Joung; Chae, Jeong Ryong; Han, Weon Cheol; Shin, Yu-Su; Kim, Eun-Kyung

2016-01-01

Recent reports have shown the immunomodulatory effect of heat-killed lactic acid bacteria. Atopic dermatitis (AD) is an allergic skin disease, caused by immune dysregulation among other factors. The aim of this study was to assess the effect of heat-killed Enterococcus faecalis EF-2001 (EF-2001) on AD. We established an in vivo AD model by repeated local exposure of Dermatophagoides farinae extract (DFE; house dust mite extract) and 2,4-dinitrochlorobenzene (DNCB) to the ears of mice. After oral administration of EF-2001 for four weeks, the epidermal and dermal ear thickness, mast cell infiltration, and serum immunoglobulin levels were measured. In addition, the gene expression levels of pathogenic cytokines in the ears, lymph nodes, and splenocytes were assayed. EF-2001 attenuated AD symptoms based on the ear thickness, histopathological analysis, and serum immunoglobulin levels. Moreover, EF-2001 decreased the DFE/DNCB-induced expression of various pathogenic cytokines in the ears, lymph nodes, and splenocytes. These results suggest that EF-2001 has therapeutic potential in the treatment of AD owing to its immunomodulatory effects. PMID:26959058

Heat-Killed Enterococcus faecalis EF-2001 Ameliorates Atopic Dermatitis in a Murine Model

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Eun-Ju Choi

2016-03-01

Full Text Available Recent reports have shown the immunomodulatory effect of heat-killed lactic acid bacteria. Atopic dermatitis (AD is an allergic skin disease, caused by immune dysregulation among other factors. The aim of this study was to assess the effect of heat-killed Enterococcus faecalis EF-2001 (EF-2001 on AD. We established an in vivo AD model by repeated local exposure of Dermatophagoides farinae extract (DFE; house dust mite extract and 2,4-dinitrochlorobenzene (DNCB to the ears of mice. After oral administration of EF-2001 for four weeks, the epidermal and dermal ear thickness, mast cell infiltration, and serum immunoglobulin levels were measured. In addition, the gene expression levels of pathogenic cytokines in the ears, lymph nodes, and splenocytes were assayed. EF-2001 attenuated AD symptoms based on the ear thickness, histopathological analysis, and serum immunoglobulin levels. Moreover, EF-2001 decreased the DFE/DNCB-induced expression of various pathogenic cytokines in the ears, lymph nodes, and splenocytes. These results suggest that EF-2001 has therapeutic potential in the treatment of AD owing to its immunomodulatory effects.

On Latent Growth Models for Composites and Their Constituents.

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Hancock, Gregory R; Mao, Xiulin; Kher, Hemant

2013-09-01

Over the last decade and a half, latent growth modeling has become an extremely popular and versatile technique for evaluating longitudinal change and its determinants. Most common among the models applied are those for a single measured variable over time. This model has been extended in a variety of ways, most relevant for the current work being the multidomain and the second-order latent growth models. Whereas the former allows for growth function characteristics to be modeled for multiple outcomes simultaneously, with the degree of growth characteristics' relations assessed within the model (e.g., cross-domain slope factor correlations), the latter models growth in latent outcomes, each of which has effect indicators repeated over time. But what if one has an outcome that is believed to be formative relative to its indicator variables rather than latent? In this case, where the outcome is a composite of multiple constituents, modeling change over time is less straightforward. This article provides analytical and applied details for simultaneously modeling growth in composites and their constituent elements, including a real data example using a general computer self-efficacy questionnaire.

eEF-2 Phosphorylation Down-Regulates P-Glycoprotein Over-Expression in Rat Brain Microvessel Endothelial Cells.

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Xing Hua Tang

Full Text Available We investigated whether glutamate, NMDA receptors, and eukaryote elongation factor-2 kinase (eEF-2K/eEF-2 regulate P-glycoprotein expression, and the effects of the eEF-2K inhibitor NH125 on the expression of P-glycoprotein in rat brain microvessel endothelial cells (RBMECs.Cortex was obtained from newborn Wistar rat brains. After surface vessels and meninges were removed, the pellet containing microvessels was resuspended and incubated at 37°C in culture medium. Cell viability was assessed by the MTT assay. RBMECs were identified by immunohistochemistry with anti-vWF. P-glycoprotein, phospho-eEF-2, and eEF-2 expression were determined by western blot analysis. Mdr1a gene expression was analyzed by RT-PCR.Mdr1a mRNA, P-glycoprotein and phospho-eEF-2 expression increased in L-glutamate stimulated RBMECs. P-glycoprotein and phospho-eEF-2 expression were down-regulated after NH125 treatment in L-glutamate stimulated RBMECs.eEF-2K/eEF-2 should have played an important role in the regulation of P-glycoprotein expression in RBMECs. eEF-2K inhibitor NH125 could serve as an efficacious anti-multidrug resistant agent.

Up-regulation of eEF1A2 promotes proliferation and inhibits apoptosis in prostate cancer

International Nuclear Information System (INIS)

Sun, Yue; Du, Chengli; Wang, Bo; Zhang, Yanling; Liu, Xiaoyan; Ren, Guoping

2014-01-01

Highlights: • The expression of eEF1A2 is up-regulated in prostate cancer tissues. • Suppression of eEF1A2 inhibits the proliferation and promotes apoptosis. • Inhibition of eEF1A2 enhances the expression of apoptotic relevant proteins. • The expressions of eEF1A2 and cleavage-caspase3 are inversely correlated. - Abstract: Background: eEF1A2 is a protein translation factor involved in protein synthesis, which possesses important function roles in cancer development. This study aims at investigating the expression pattern of eEF1A2 in prostate cancer and its potential role in prostate cancer development. Methods: We examined the expression level of eEF1A2 in 30 pairs of prostate cancer tissues by using RT-PCR and immunohistochemical staining (IHC). Then we applied siRNA specifically targeting eEF1A2 to down-regulate its expression in DU-145 and PC-3 cells. Flow cytometer was used to explore apoptosis and Western-blot was used to detect the pathway proteins of apoptosis. Results: Our results showed that the expression level of eEF1A2 in prostate cancer tissues was significantly higher compared to their corresponding normal tissues. Reduction of eEF1A2 expression in DU-145 and PC-3 cells led to a dramatic inhibition of proliferation accompanied with enhanced apoptosis rate. Western blot revealed that apoptosis pathway proteins (caspase3, BAD, BAX, PUMA) were significantly up-regulated after suppression of eEF1A2. More importantly, the levels of eEF1A2 and caspase3 were inversely correlated in prostate cancer tissues. Conclusion: Our data suggests that eEF1A2 plays an important role in prostate cancer development, especially in inhibiting apoptosis. So eEF1A2 might serve as a potential therapeutic target in prostate cancer

In vivo and in vitro suppression of hepatocellular carcinoma by EF24, a curcumin analog.

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Haitao Liu

Full Text Available The synthetic compound 3,5-bis(2-flurobenzylidenepiperidin-4-one (EF24 is a potent analog of curcumin that exhibits enhanced biological activity and bioavailability without increasing toxicity. EF24 exerts antitumor activity by arresting the cell cycle and inducing apoptosis, suppressing many types of cancer cells in vitro. The antiproliferative and antiangiogenic properties of EF24 provide theoretical support for its development and application to liver cancers. We investigated the in vitro and in vivo activities of EF24 on liver cancer to better understand its therapeutic effects and mechanisms. EF24 induced significant apoptosis and G2/M-phase cell cycle arrest in mouse liver cancer cell lines, Hepa1-6 and H22. The expression levels of G2/M cell cycle regulating factors, cyclin B1 and Cdc2, were significantly decreased, pp53, p53, and p21 were significantly increased in EF24-treated cells. In addition, EF24 treatment significantly reduced Bcl-2 concomitant with an increase in Bax, enhanced the release of cytochrome c from the mitochondria into the cytosol, resulting in an upregulation of cleaved-caspase-3, which promoted poly (ADP-ribose polymerase cleavage. EF24-treated cells also displayed decreases in phosphorylated Akt, phosphorylated extracellular signal-regulated kinase and vascular endothelial growth factor. Our in vitro protein expression data were confirmed in vivo using a subcutaneous hepatocellular carcinoma (HCC tumor model. This mouse HCC model confirmed that total body weight was unchanged following EF24 treatment, although tumor weight was significantly decreased. Using an orthotopic HCC model, EF24 significantly reduced the liver/body weight ratio and relative tumor areas compared to the control group. In situ detection of apoptotic cells and quantification of Ki-67, a biomarker of cell proliferation, all indicated significant tumor suppression with EF24 treatment. These results suggest that EF24 exhibits anti-tumor activity

A coarse to fine minutiae-based latent palmprint matching.

Science.gov (United States)

Liu, Eryun; Jain, Anil K; Tian, Jie

2013-10-01

With the availability of live-scan palmprint technology, high resolution palmprint recognition has started to receive significant attention in forensics and law enforcement. In forensic applications, latent palmprints provide critical evidence as it is estimated that about 30 percent of the latents recovered at crime scenes are those of palms. Most of the available high-resolution palmprint matching algorithms essentially follow the minutiae-based fingerprint matching strategy. Considering the large number of minutiae (about 1,000 minutiae in a full palmprint compared to about 100 minutiae in a rolled fingerprint) and large area of foreground region in full palmprints, novel strategies need to be developed for efficient and robust latent palmprint matching. In this paper, a coarse to fine matching strategy based on minutiae clustering and minutiae match propagation is designed specifically for palmprint matching. To deal with the large number of minutiae, a local feature-based minutiae clustering algorithm is designed to cluster minutiae into several groups such that minutiae belonging to the same group have similar local characteristics. The coarse matching is then performed within each cluster to establish initial minutiae correspondences between two palmprints. Starting with each initial correspondence, a minutiae match propagation algorithm searches for mated minutiae in the full palmprint. The proposed palmprint matching algorithm has been evaluated on a latent-to-full palmprint database consisting of 446 latents and 12,489 background full prints. The matching results show a rank-1 identification accuracy of 79.4 percent, which is significantly higher than the 60.8 percent identification accuracy of a state-of-the-art latent palmprint matching algorithm on the same latent database. The average computation time of our algorithm for a single latent-to-full match is about 141 ms for genuine match and 50 ms for impostor match, on a Windows XP desktop system with 2

Longitudinal Physical Activity Patterns Among Older Adults: A Latent Transition Analysis.

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Mooney, Stephen J; Joshi, Spruha; Cerdá, Magdalena; Kennedy, Gary J; Beard, John R; Rundle, Andrew G

2018-05-14

Most epidemiologic studies of physical activity measure either total energy expenditure or engagement in a single activity type, such as walking. These approaches may gloss over important nuances in activity patterns. We performed a latent transition analysis to identify patterns of activity types as well as neighborhood and individual determinants of changes in those activity patterns over two years in a cohort of 2,023 older adult residents of New York City, NY, surveyed between 2011 and 2013. We identified seven latent classes: 1) Mostly Inactive, 2) Walking, 3) Exercise, 4) Household Activities and Walking, 5) Household Activities and Exercise, 6) Gardening and Household Activities, and 7) Gardening, Household Activities, and Exercise. The majority of subjects retained the same activity patterns between waves (54% unchanged between waves 1 and 2, 66% unchanged between waves 2 and 3).Most latent class transitions were between classes distinguished only by one form of activity, and only neighborhood unemployment was consistently associated with changing between activity latent classes. Future latent transition analyses of physical activity would benefit from larger cohorts and longer follow-up periods to assess predictors of and long-term impacts of changes in activity patterns.

Evolution of EF-hand calcium-modulated proteins. IV. Exon shuffling did not determine the domain compositions of EF-hand proteins

Science.gov (United States)

Kretsinger, R. H.; Nakayama, S.

1993-01-01

In the previous three reports in this series we demonstrated that the EF-hand family of proteins evolved by a complex pattern of gene duplication, transposition, and splicing. The dendrograms based on exon sequences are nearly identical to those based on protein sequences for troponin C, the essential light chain myosin, the regulatory light chain, and calpain. This validates both the computational methods and the dendrograms for these subfamilies. The proposal of congruence for calmodulin, troponin C, essential light chain, and regulatory light chain was confirmed. There are, however, significant differences in the calmodulin dendrograms computed from DNA and from protein sequences. In this study we find that introns are distributed throughout the EF-hand domain and the interdomain regions. Further, dendrograms based on intron type and distribution bear little resemblance to those based on protein or on DNA sequences. We conclude that introns are inserted, and probably deleted, with relatively high frequency. Further, in the EF-hand family exons do not correspond to structural domains and exon shuffling played little if any role in the evolution of this widely distributed homolog family. Calmodulin has had a turbulent evolution. Its dendrograms based on protein sequence, exon sequence, 3'-tail sequence, intron sequences, and intron positions all show significant differences.

Latent Fundamentals Arbitrage with a Mixed Effects Factor Model

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Andrei Salem Gonçalves

2012-09-01

Full Text Available We propose a single-factor mixed effects panel data model to create an arbitrage portfolio that identifies differences in firm-level latent fundamentals. Furthermore, we show that even though the characteristics that affect returns are unknown variables, it is possible to identify the strength of the combination of these latent fundamentals for each stock by following a simple approach using historical data. As a result, a trading strategy that bought the stocks with the best fundamentals (strong fundamentals portfolio and sold the stocks with the worst ones (weak fundamentals portfolio realized significant risk-adjusted returns in the U.S. market for the period between July 1986 and June 2008. To ensure robustness, we performed sub period and seasonal analyses and adjusted for trading costs and we found further empirical evidence that using a simple investment rule, that identified these latent fundamentals from the structure of past returns, can lead to profit.

delta-EF1 is a negative regulator of Ihh in the developing growth plate.

Science.gov (United States)

Bellon, Ellen; Luyten, Frank P; Tylzanowski, Przemko

2009-11-30

Indian hedgehog (Ihh) regulates proliferation and differentiation of chondrocytes in the growth plate. Although the biology of Ihh is currently well documented, its transcriptional regulation is poorly understood. delta-EF1 is a two-handed zinc finger/homeodomain transcriptional repressor. Targeted inactivation of mouse delta-EF1 leads to skeletal abnormalities including disorganized growth plates, shortening of long bones, and joint fusions, which are reminiscent of defects associated with deregulation of Ihh signaling. Here, we show that the absence of delta-EF1 results in delayed hypertrophic differentiation of chondrocytes and increased cell proliferation in the growth plate. Further, we demonstrate that delta-EF1 binds to the putative regulatory elements in intron 1 of Ihh in vitro and in vivo, resulting in down-regulation of Ihh expression. Finally, we show that delta-EF1 haploinsufficiency leads to a postnatal increase in trabecular bone mass associated with enhanced Ihh expression. In summary, we have identified delta-EF1 as an in vivo negative regulator of Ihh expression in the growth plate.

Structure of eEF3 and the mechanism of transfer RNA release from the E-site

DEFF Research Database (Denmark)

Andersen, Christian Brix Folsted; Becker, T.; Blau, M.

2006-01-01

Elongation factor eEF3 is an ATPase, which, in addition to the two canonical factors eEF1A and eEF2, serves an essential function in the translation cycle of fungi. eEF3 is required for the binding of the aatRNA-eEF1A-GTP ternary complex to the ribosomal A-site and has been suggested to facilitate...... the clearance of deacyl-tRNA from the E-site. Here, we present the crystal structure of eEF3 showing that it consists of an N-terminal HEAT repeat domain, followed by a four-helix bundle and two ABC-type ATPase domains with a chromo-domain inserted in ABC2. Moreover, we present the cryo-EM structure of the ATP......-bound form of eEF3 in complex with the post-translocational state 80S ribosome from yeast. eEF3 uses an entirely new factor binding site near the ribosomal E-site, with the chromodomain stabilizing the ribosomal L1 stalk in an open conformation, thus, allowing tRNA release....

Latent vs. Observed Variables : Analysis of Irrigation Water Efficiency Using SEM and SUR

NARCIS (Netherlands)

Tang, Jianjun; Folmer, Henk

In this paper we compare conceptualising single factor technical and allocative efficiency as indicators of a single latent variable, or as separate observed variables. In the former case, the impacts on both efficiency types are analysed by means of structural equationmodeling (SEM), in the latter

Polymorphisms in the mitochondrial ribosome recycling factor EF-G2mt/MEF2 compromise cell respiratory function and increase atorvastatin toxicity.

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Sylvie Callegari

Full Text Available Mitochondrial translation, essential for synthesis of the electron transport chain complexes in the mitochondria, is governed by nuclear encoded genes. Polymorphisms within these genes are increasingly being implicated in disease and may also trigger adverse drug reactions. Statins, a class of HMG-CoA reductase inhibitors used to treat hypercholesterolemia, are among the most widely prescribed drugs in the world. However, a significant proportion of users suffer side effects of varying severity that commonly affect skeletal muscle. The mitochondria are one of the molecular targets of statins, and these drugs have been known to uncover otherwise silent mitochondrial mutations. Based on yeast genetic studies, we identify the mitochondrial translation factor MEF2 as a mediator of atorvastatin toxicity. The human ortholog of MEF2 is the Elongation Factor Gene (EF-G 2, which has previously been shown to play a specific role in mitochondrial ribosome recycling. Using small interfering RNA (siRNA silencing of expression in human cell lines, we demonstrate that the EF-G2mt gene is required for cell growth on galactose medium, signifying an essential role for this gene in aerobic respiration. Furthermore, EF-G2mt silenced cell lines have increased susceptibility to cell death in the presence of atorvastatin. Using yeast as a model, conserved amino acid variants, which arise from non-synonymous single nucleotide polymorphisms (SNPs in the EF-G2mt gene, were generated in the yeast MEF2 gene. Although these mutations do not produce an obvious growth phenotype, three mutations reveal an atorvastatin-sensitive phenotype and further analysis uncovers a decreased respiratory capacity. These findings constitute the first reported phenotype associated with SNPs in the EF-G2mt gene and implicate the human EF-G2mt gene as a pharmacogenetic candidate gene for statin toxicity in humans.

Dual-Polarimetric Radar-Based Tornado Debris Paths Associated with EF-4 and EF-5 Tornadoes over Northern Alabama During the Historic Outbreak of 27 April 2011

Science.gov (United States)

Carey, Lawrence D.; Schultz, Chrstopher J.; Schultz, Elise V.; Petersen, Walter A.; Gatlin, Patrick N.; Knupp, Kevin R.; Molthan, Andrew L.; Jedlovec, Gary J.; Darden, Christopher B.

2012-01-01

An historic tornado and severe weather outbreak devastated much of the southeastern United States between 25 and 28 April 2011. On 27 April 2011, northern Alabama was particularly hard hit by a large number of tornadoes, including several that reached EF-4 and EF-5 on the Enhanced Fujita damage scale. In northern Alabama alone, there were approximately 100 fatalities and hundreds of more people who were injured or lost their homes during the havoc caused by these violent tornadic storms. Two long-track and violent (EF-4 and EF-5) tornadoes occurred within range of the University of Alabama in Huntsville (UAHuntsville) Advanced Radar for Meteorological and Operational Research (ARMOR, C-band dual-polarimetric). A unique capability of dual-polarimetric radar is the near-real time identification of lofted debris associated with ongoing tornadoes on the ground. The focus of this paper is to analyze the dual-polarimetric radar-inferred tornado debris signatures and identify the associated debris paths of the long-track EF-4 and EF-5 tornadoes near ARMOR. The relative locations of the debris and damage paths for each tornado will be ascertained by careful comparison of the ARMOR analysis with NASA MODIS (Moderate Resolution Imaging Spectroradiometer) and ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) satellite imagery of the tornado damage scenes and the National Weather Service tornado damage surveys. With the ongoing upgrade of the WSR-88D (Weather Surveillance Radar 1988 Doppler) operational network to dual-polarimetry and a similar process having already taken place or ongoing for many private sector radars, dual-polarimetric radar signatures of tornado debris promise the potential to assist in the situational awareness of government and private sector forecasters and emergency managers during tornadic events. As such, a companion abstract (Schultz et al.) also submitted to this conference explores The use of dual-polarimetric tornadic debris

Latent-trait latent-class analysis of selfdisclosure in the work environment

NARCIS (Netherlands)

Maij - de Meij, A.M.; Kelderman, H.; van der Flier, H.

2006-01-01

Based on the literature about self-disclosure, it was hypothesized that different groups of subjects differ in their pattern of self-disclosure with respect to different areas of social interaction. An extended latent-trait latent-class model was proposed to describe these general patterns of

Latent-trait latent-class analysis of selfdisclosure in the work environment

NARCIS (Netherlands)

Maij - de Meij, A.M.; Kelderman, H.; van der Flier, H.

2005-01-01

Based on the literature about self-disclosure, it was hypothesized that different groups of subjects differ in their pattern of self-disclosure with respect to different areas of social interaction. An extended latent-trait latent-class model was proposed to describe these general patterns of

Gene variants associated with antisocial behaviour: a latent variable approach.

Science.gov (United States)

Bentley, Mary Jane; Lin, Haiqun; Fernandez, Thomas V; Lee, Maria; Yrigollen, Carolyn M; Pakstis, Andrew J; Katsovich, Liliya; Olds, David L; Grigorenko, Elena L; Leckman, James F

2013-10-01

The aim of this study was to determine if a latent variable approach might be useful in identifying shared variance across genetic risk alleles that is associated with antisocial behaviour at age 15 years. Using a conventional latent variable approach, we derived an antisocial phenotype in 328 adolescents utilizing data from a 15-year follow-up of a randomized trial of a prenatal and infancy nurse-home visitation programme in Elmira, New York. We then investigated, via a novel latent variable approach, 450 informative genetic polymorphisms in 71 genes previously associated with antisocial behaviour, drug use, affiliative behaviours and stress response in 241 consenting individuals for whom DNA was available. Haplotype and Pathway analyses were also performed. Eight single-nucleotide polymorphisms (SNPs) from eight genes contributed to the latent genetic variable that in turn accounted for 16.0% of the variance within the latent antisocial phenotype. The number of risk alleles was linearly related to the latent antisocial variable scores. Haplotypes that included the putative risk alleles for all eight genes were also associated with higher latent antisocial variable scores. In addition, 33 SNPs from 63 of the remaining genes were also significant when added to the final model. Many of these genes interact on a molecular level, forming molecular networks. The results support a role for genes related to dopamine, norepinephrine, serotonin, glutamate, opioid and cholinergic signalling as well as stress response pathways in mediating susceptibility to antisocial behaviour. This preliminary study supports use of relevant behavioural indicators and latent variable approaches to study the potential 'co-action' of gene variants associated with antisocial behaviour. It also underscores the cumulative relevance of common genetic variants for understanding the aetiology of complex behaviour. If replicated in future studies, this approach may allow the identification of a

Interleukin-11 binds specific EF-hand proteins via their conserved structural motifs.

Science.gov (United States)

Kazakov, Alexei S; Sokolov, Andrei S; Vologzhannikova, Alisa A; Permyakova, Maria E; Khorn, Polina A; Ismailov, Ramis G; Denessiouk, Konstantin A; Denesyuk, Alexander I; Rastrygina, Victoria A; Baksheeva, Viktoriia E; Zernii, Evgeni Yu; Zinchenko, Dmitry V; Glazatov, Vladimir V; Uversky, Vladimir N; Mirzabekov, Tajib A; Permyakov, Eugene A; Permyakov, Sergei E

2017-01-01

Interleukin-11 (IL-11) is a hematopoietic cytokine engaged in numerous biological processes and validated as a target for treatment of various cancers. IL-11 contains intrinsically disordered regions that might recognize multiple targets. Recently we found that aside from IL-11RA and gp130 receptors, IL-11 interacts with calcium sensor protein S100P. Strict calcium dependence of this interaction suggests a possibility of IL-11 interaction with other calcium sensor proteins. Here we probed specificity of IL-11 to calcium-binding proteins of various types: calcium sensors of the EF-hand family (calmodulin, S100B and neuronal calcium sensors: recoverin, NCS-1, GCAP-1, GCAP-2), calcium buffers of the EF-hand family (S100G, oncomodulin), and a non-EF-hand calcium buffer (α-lactalbumin). A specific subset of the calcium sensor proteins (calmodulin, S100B, NCS-1, GCAP-1/2) exhibits metal-dependent binding of IL-11 with dissociation constants of 1-19 μM. These proteins share several amino acid residues belonging to conservative structural motifs of the EF-hand proteins, 'black' and 'gray' clusters. Replacements of the respective S100P residues by alanine drastically decrease its affinity to IL-11, suggesting their involvement into the association process. Secondary structure and accessibility of the hinge region of the EF-hand proteins studied are predicted to control specificity and selectivity of their binding to IL-11. The IL-11 interaction with the EF-hand proteins is expected to occur under numerous pathological conditions, accompanied by disintegration of plasma membrane and efflux of cellular components into the extracellular milieu.

POTENTIAL MARKETING PLAN FOR EF, REGARDING LANGUAGE COURSES IN CHINA

OpenAIRE

Saarni, Helena

2017-01-01

This bachelor’s thesis was conducted as a potential marketing plan for EF. The aim and purpose of the project was to create a marketing plan for a company called EF regarding their Chinese language courses in China, where they offer these courses to young adults already. These courses however are not marketed in Finland as much as the other language courses. The theoretical part was gathered by collecting information and theories from various sources including books and e-books about mark...

Liposome-encapsulated EF24-HPβCD inclusion complex: a preformulation study and biodistribution in a rat model

International Nuclear Information System (INIS)

Agashe, H.; Lagisetty, P.; Sahoo, K.; Bourne, D.; Grady, B.; Awasthi, V.

2011-01-01

3,5-Bis(2-fluorobenzylidene)-4-piperidone (EF24) is an anti-proliferative diphenyldifluoroketone analog of curcumin with more potent activity. The authors describe a liposome preparation of EF24 using a “drug-in-CD-in liposome” approach. An aqueous solution of EF24 and hydroxypropyl-β-cyclodextrin (HPβCD) inclusion complex (IC) was used to prepare EF24 liposomes. The liposome size was reduced by a combination of multiple freeze–thaw cycles. Co-encapsulation of glutathione inside the liposomes conferred them with the capability of labeling with imageable radionuclide Tc-99m. Phase solubility analysis of EF24-HPβCD mixture provided k 1:1 value of 9.9 M −1 . The enhanced aqueous solubility of EF24 (from 1.64 to 13.8 mg/mL) due to the presence of HPβCD helped in the liposome preparation. About 19% of the EF24 IC was encapsulated inside the liposomes (320.5 ± 2.6 nm) by dehydration–rehydration technique. With extrusion technique, the size of 177 ± 6.5 nm was obtained without any effect on encapsulation efficiency. The EF24-liposomes were evaluated for anti-proliferative activity in lung adenocarcinoma H441 and prostate cancer PC-3 cells. The EF24-liposomes demonstrated anti-proliferative activity superior to that of plain EF24 at 10 μM dose. When injected in rats, the Tc-99m-labeled EF24-liposomes cleared from blood with an α-t 1/2 of 21.4 min and β-t 1/2 of 397 min. Tissue radioactivity counting upon necropsy showed that the majority of clearance was due to the uptake in liver and spleen. The results suggest that using “drug-in-CD-in liposome” approach is a feasible strategy to formulate an effective parenteral preparation of EF24. In vitro studies show that the liposomal EF24 remains anti-proliferative, while presenting an opportunity to image its biodistribution.

Liposome-encapsulated EF24-HPβCD inclusion complex: a preformulation study and biodistribution in a rat model

Science.gov (United States)

Agashe, H.; Lagisetty, P.; Sahoo, K.; Bourne, D.; Grady, B.; Awasthi, V.

2011-06-01

3,5-Bis(2-fluorobenzylidene)-4-piperidone (EF24) is an anti-proliferative diphenyldifluoroketone analog of curcumin with more potent activity. The authors describe a liposome preparation of EF24 using a "drug-in-CD-in liposome" approach. An aqueous solution of EF24 and hydroxypropyl-β-cyclodextrin (HPβCD) inclusion complex (IC) was used to prepare EF24 liposomes. The liposome size was reduced by a combination of multiple freeze-thaw cycles. Co-encapsulation of glutathione inside the liposomes conferred them with the capability of labeling with imageable radionuclide Tc-99m. Phase solubility analysis of EF24-HPβCD mixture provided k 1:1 value of 9.9 M-1. The enhanced aqueous solubility of EF24 (from 1.64 to 13.8 mg/mL) due to the presence of HPβCD helped in the liposome preparation. About 19% of the EF24 IC was encapsulated inside the liposomes (320.5 ± 2.6 nm) by dehydration-rehydration technique. With extrusion technique, the size of 177 ± 6.5 nm was obtained without any effect on encapsulation efficiency. The EF24-liposomes were evaluated for anti-proliferative activity in lung adenocarcinoma H441 and prostate cancer PC-3 cells. The EF24-liposomes demonstrated anti-proliferative activity superior to that of plain EF24 at 10 μM dose. When injected in rats, the Tc-99m-labeled EF24-liposomes cleared from blood with an α- t 1/2 of 21.4 min and β- t 1/2 of 397 min. Tissue radioactivity counting upon necropsy showed that the majority of clearance was due to the uptake in liver and spleen. The results suggest that using "drug-in-CD-in liposome" approach is a feasible strategy to formulate an effective parenteral preparation of EF24. In vitro studies show that the liposomal EF24 remains anti-proliferative, while presenting an opportunity to image its biodistribution.

A randomized study on migration of the Spectron EF and the Charnley flanged 40 cemented femoral components using radiostereometric analysis at 2 years.

Science.gov (United States)

Kadar, Thomas; Hallan, Geir; Aamodt, Arild; Indrekvam, Kari; Badawy, Mona; Havelin, Leif Ivar; Stokke, Terje; Haugan, Kristin; Espehaug, Birgitte; Furnes, Ove

2011-10-01

We performed a randomized study to determine the migration patterns of the Spectron EF femoral stem and to compare them with those of the Charnley stem, which is regarded by many as the gold standard for comparison of implants due to its extensive documentation. 150 patients with a mean age of 70 years were randomized, single-blinded, to receive either a cemented Charnley flanged 40 monoblock, stainless steel, vaquasheen surface femoral stem with a 22.2-mm head (n = 30) or a cemented Spectron EF modular, matte, straight, collared, cobalt-chrome femoral stem with a 28-mm femoral head and a roughened proximal third of the stem (n = 120). The patients were followed with repeated radiostereometric analysis for 2 years to assess migration. At 2 years, stem retroversion was 2.3° and 0.7° (p < 0.001) and posterior translation was 0.44 mm and 0.17 mm (p = 0.002) for the Charnley group (n = 26) and the Spectron EF group (n = 74), respectively. Subsidence was 0.26 mm for the Charnley and 0.20 mm for the Spectron EF (p = 0.5). The Spectron EF femoral stem was more stable than the Charnley flanged 40 stem in our study when evaluated at 2 years. In a report from the Norwegian arthroplasty register, the Spectron EF stem had a higher revision rate due to aseptic loosening beyond 5 years than the Charnley. Initial stability is not invariably related to good long-term results. Our results emphasize the importance of prospective long-term follow-up of prosthetic implants in clinical trials and national registries and a stepwise introduction of implants.

Duplication of Drosophila melanogaster mitochondrial EF-Tu: pre-adaptation to T-arm truncation and exclusion of bulky aminoacyl residues.

Science.gov (United States)

Sato, Aya; Suematsu, Takuma; Aihara, Koh-Ki; Kita, Kiyoshi; Suzuki, Tsutomu; Watanabe, Kimitsuna; Ohtsuki, Takashi; Watanabe, Yoh-Ichi

2017-03-07

Translation elongation factor Tu (EF-Tu) delivers aminoacyl-tRNA (aa-tRNA) to ribosomes in protein synthesis. EF-Tu generally recognizes aminoacyl moieties and acceptor- and T-stems of aa-tRNAs. However, nematode mitochondrial (mt) tRNAs frequently lack all or part of the T-arm that is recognized by canonical EF-Tu. We previously reported that two distinct EF-Tu species, EF-Tu1 and EF-Tu2, respectively, recognize mt tRNAs lacking T-arms and D-arms in the mitochondria of the chromadorean nematode Caenorhabditis elegans C. elegans EF-Tu2 specifically recognizes the seryl moiety of serylated D-armless tRNAs. Mitochondria of the enoplean nematode Trichinella possess three structural types of tRNAs: T-armless tRNAs, D-armless tRNAs, and cloverleaf tRNAs with a short T-arm. Trichinella mt EF-Tu1 binds to all three types and EF-Tu2 binds only to D-armless Ser-tRNAs, showing an evolutionary intermediate state from canonical EF-Tu to chromadorean nematode (e.g. C. elegans ) EF-Tu species. We report here that two EF-Tu species also participate in Drosophila melanogaster mitochondria. Both D. melanogaster EF-Tu1 and EF-Tu2 bound to cloverleaf and D-armless tRNAs. D. melanogaster EF-Tu1 has the ability to recognize T-armless tRNAs that do not evidently exist in D. melanogaster mitochondria, but do exist in related arthropod species. In addition, D. melanogaster EF-Tu2 preferentially bound to aa-tRNAs carrying small amino acids, but not to aa-tRNAs carrying bulky amino acids. These results suggest that the Drosophila mt translation system could be another intermediate state between the canonical and nematode mitochondria-type translation systems. © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

Using multiple biomarkers and determinants to obtain a better measurement of oxidative stress: a latent variable structural equation model approach.

Science.gov (United States)

Eldridge, Ronald C; Flanders, W Dana; Bostick, Roberd M; Fedirko, Veronika; Gross, Myron; Thyagarajan, Bharat; Goodman, Michael

2017-09-01

Since oxidative stress involves a variety of cellular changes, no single biomarker can serve as a complete measure of this complex biological process. The analytic technique of structural equation modeling (SEM) provides a possible solution to this problem by modelling a latent (unobserved) variable constructed from the covariance of multiple biomarkers. Using three pooled datasets, we modelled a latent oxidative stress variable from five biomarkers related to oxidative stress: F 2 -isoprostanes (FIP), fluorescent oxidation products, mitochondrial DNA copy number, γ-tocopherol (Gtoc) and C-reactive protein (CRP, an inflammation marker closely linked to oxidative stress). We validated the latent variable by assessing its relation to pro- and anti-oxidant exposures. FIP, Gtoc and CRP characterized the latent oxidative stress variable. Obesity, smoking, aspirin use and β-carotene were statistically significantly associated with oxidative stress in the theorized directions; the same exposures were weakly and inconsistently associated with the individual biomarkers. Our results suggest that using SEM with latent variables decreases the biomarker-specific variability, and may produce a better measure of oxidative stress than do single variables. This methodology can be applied to similar areas of research in which a single biomarker is not sufficient to fully describe a complex biological phenomenon.

Do gamblers eat more salt? Testing a latent trait model of covariance in consumption.

Science.gov (United States)

Goodwin, Belinda C; Browne, Matthew; Rockloff, Matthew; Donaldson, Phillip

2015-09-01

A diverse class of stimuli, including certain foods, substances, media, and economic behaviours, may be described as 'reward-oriented' in that they provide immediate reinforcement with little initial investment. Neurophysiological and personality concepts, including dopaminergic dysfunction, reward sensitivity and rash impulsivity, each predict the existence of a latent behavioural trait that leads to increased consumption of all stimuli in this class. Whilst bivariate relationships (co-morbidities) are often reported in the literature, to our knowledge, a multivariate investigation of this possible trait has not been done. We surveyed 1,194 participants (550 male) on their typical weekly consumption of 11 types of reward-oriented stimuli, including fast food, salt, caffeine, television, gambling products, and illicit drugs. Confirmatory factor analysis was used to compare models in a 3×3 structure, based on the definition of a single latent factor (none, fixed loadings, or estimated loadings), and assumed residual covariance structure (none, a-priori / literature based, or post-hoc / data-driven). The inclusion of a single latent behavioural 'consumption' factor significantly improved model fit in all cases. Also confirming theoretical predictions, estimated factor loadings on reward-oriented indicators were uniformly positive, regardless of assumptions regarding residual covariances. Additionally, the latent trait was found to be negatively correlated with the non-reward-oriented indicators of fruit and vegetable consumption. The findings support the notion of a single behavioural trait leading to increased consumption of reward-oriented stimuli across multiple modalities. We discuss implications regarding the concentration of negative lifestyle-related health behaviours.

The Effect of dcEFs on migration behavior of A549 cells and Integrin beta1 expression

Directory of Open Access Journals (Sweden)

Yunjie WANG

2008-04-01

Full Text Available Background and objective The effect of direct-current electric fields (dcEFs on cells attracted extensive attention. Moreover the metastasis and its potential are considered to be related to dcEFs. The aim is to study the effect of dcEFs on migration behavior of A549 cells, Integrin ?1 and its signal pathways. Methods According to exposure to 5 V/cm dcEFs or not and the time of exposure, the A549 cells were divided into 4 groups. Images were taken per 5 min within 2 h to recode the migration of the cells. The data of results were analyzed statistically. Results Most of A549cells exposed to the dcEFs aligned and elongated perpendicularly to the electric field lines and migrated to the cathode continually during 2 h. On the contrary, cells unexposed to dcEFs showed slightly random movements. Immunofluorescence showed that Integrin ?1 on plasma membrane polarized to the cathode of the dcEFs. Western blot showed that Integrin beta1 downstream signal pathways p-FAK and p-ERK were overexpressed in the dcEFs. Conclusion A549 cells have a galvanotatic feature of cathodal directed migration while exposed to the dcEFs. The polarization of Integrin beta1 and the promotion of its downstream signal pathways may play an important roles in the galvanotaxis of A549 cells.

Latent-Trait Latent-Class Analysis of Self-disclosure in the Work Environment

NARCIS (Netherlands)

Maij - de Meij, A.M.; Kelderman, H.; van der Flier, H.

2005-01-01

Based on the literature about self-disclosure, it was hypothesized that different groups of subjects differ in their pattern of self-disclosure with respect to different areas of social interaction. An extended latent-trait latent-class model was proposed to describe these general patterns of

Latent classification models

DEFF Research Database (Denmark)

Langseth, Helge; Nielsen, Thomas Dyhre

2005-01-01

parametric family ofdistributions.  In this paper we propose a new set of models forclassification in continuous domains, termed latent classificationmodels. The latent classification model can roughly be seen ascombining the \\NB model with a mixture of factor analyzers,thereby relaxing the assumptions...... classification model, and wedemonstrate empirically that the accuracy of the proposed model issignificantly higher than the accuracy of other probabilisticclassifiers....

Liposome-encapsulated EF24-HP{beta}CD inclusion complex: a preformulation study and biodistribution in a rat model

Energy Technology Data Exchange (ETDEWEB)

Agashe, H; Lagisetty, P; Sahoo, K; Bourne, D [University of Oklahoma Health Sciences Center, Department of Pharmaceutical Sciences (United States); Grady, B [School of Chemical, Biological and Materials Engineering (United States); Awasthi, V [University of Oklahoma Health Sciences Center, Department of Pharmaceutical Sciences (United States)

2011-06-15

3,5-Bis(2-fluorobenzylidene)-4-piperidone (EF24) is an anti-proliferative diphenyldifluoroketone analog of curcumin with more potent activity. The authors describe a liposome preparation of EF24 using a 'drug-in-CD-in liposome' approach. An aqueous solution of EF24 and hydroxypropyl-{beta}-cyclodextrin (HP{beta}CD) inclusion complex (IC) was used to prepare EF24 liposomes. The liposome size was reduced by a combination of multiple freeze-thaw cycles. Co-encapsulation of glutathione inside the liposomes conferred them with the capability of labeling with imageable radionuclide Tc-99m. Phase solubility analysis of EF24-HP{beta}CD mixture provided k{sub 1:1} value of 9.9 M{sup -1}. The enhanced aqueous solubility of EF24 (from 1.64 to 13.8 mg/mL) due to the presence of HP{beta}CD helped in the liposome preparation. About 19% of the EF24 IC was encapsulated inside the liposomes (320.5 {+-} 2.6 nm) by dehydration-rehydration technique. With extrusion technique, the size of 177 {+-} 6.5 nm was obtained without any effect on encapsulation efficiency. The EF24-liposomes were evaluated for anti-proliferative activity in lung adenocarcinoma H441 and prostate cancer PC-3 cells. The EF24-liposomes demonstrated anti-proliferative activity superior to that of plain EF24 at 10 {mu}M dose. When injected in rats, the Tc-99m-labeled EF24-liposomes cleared from blood with an {alpha}-t{sub 1/2} of 21.4 min and {beta}-t{sub 1/2} of 397 min. Tissue radioactivity counting upon necropsy showed that the majority of clearance was due to the uptake in liver and spleen. The results suggest that using 'drug-in-CD-in liposome' approach is a feasible strategy to formulate an effective parenteral preparation of EF24. In vitro studies show that the liposomal EF24 remains anti-proliferative, while presenting an opportunity to image its biodistribution.

Liposome-encapsulated EF24-HP{beta}CD inclusion complex: a preformulation study and biodistribution in a rat model

Energy Technology Data Exchange (ETDEWEB)

Agashe, H.; Lagisetty, P.; Sahoo, K.; Bourne, D. [University of Oklahoma Health Sciences Center, Department of Pharmaceutical Sciences (United States); Grady, B. [School of Chemical, Biological and Materials Engineering (United States); Awasthi, V., E-mail: vawasthi@ouhsc.edu [University of Oklahoma Health Sciences Center, Department of Pharmaceutical Sciences (United States)

2011-06-15

3,5-Bis(2-fluorobenzylidene)-4-piperidone (EF24) is an anti-proliferative diphenyldifluoroketone analog of curcumin with more potent activity. The authors describe a liposome preparation of EF24 using a 'drug-in-CD-in liposome' approach. An aqueous solution of EF24 and hydroxypropyl-{beta}-cyclodextrin (HP{beta}CD) inclusion complex (IC) was used to prepare EF24 liposomes. The liposome size was reduced by a combination of multiple freeze-thaw cycles. Co-encapsulation of glutathione inside the liposomes conferred them with the capability of labeling with imageable radionuclide Tc-99m. Phase solubility analysis of EF24-HP{beta}CD mixture provided k{sub 1:1} value of 9.9 M{sup -1}. The enhanced aqueous solubility of EF24 (from 1.64 to 13.8 mg/mL) due to the presence of HP{beta}CD helped in the liposome preparation. About 19% of the EF24 IC was encapsulated inside the liposomes (320.5 {+-} 2.6 nm) by dehydration-rehydration technique. With extrusion technique, the size of 177 {+-} 6.5 nm was obtained without any effect on encapsulation efficiency. The EF24-liposomes were evaluated for anti-proliferative activity in lung adenocarcinoma H441 and prostate cancer PC-3 cells. The EF24-liposomes demonstrated anti-proliferative activity superior to that of plain EF24 at 10 {mu}M dose. When injected in rats, the Tc-99m-labeled EF24-liposomes cleared from blood with an {alpha}-t{sub 1/2} of 21.4 min and {beta}-t{sub 1/2} of 397 min. Tissue radioactivity counting upon necropsy showed that the majority of clearance was due to the uptake in liver and spleen. The results suggest that using 'drug-in-CD-in liposome' approach is a feasible strategy to formulate an effective parenteral preparation of EF24. In vitro studies show that the liposomal EF24 remains anti-proliferative, while presenting an opportunity to image its biodistribution.

Influence of activated carbon preloading by EfOM fractions from treated wastewater on adsorption of pharmaceutically active compounds.

Science.gov (United States)

Hu, Jingyi; Shang, Ran; Heijman, Bas; Rietveld, Luuk

2016-05-01

In this study, the preloading effects of different fractions of wastewater effluent organic matter (EfOM) on the adsorption of trace-level pharmaceutically active compounds (PhACs) onto granular activated carbon (GAC) were investigated. A nanofiltration (NF) membrane was employed to separate the EfOM by size, and two GACs with distinct pore structures were chosen for comparison. The results showed that preloading with EfOM substantially decreased PhAC uptake of the GACs; however, comparable PhAC adsorption capacities were achieved on GACs preloaded by feed EfOM and the NF-permeating EfOM. This indicates that: (1) the NF-rejected, larger EfOM molecules with an expectation to block the PhAC adsorption pores exerted little impact on the adsorbability of PhACs; (2) the smaller EfOM molecules present in the NF permeate contributed mainly to the decrease in PhAC uptake, mostly due to site competition. Of the two examined GACs, the wide pore-size-distributed GAC was found to be more susceptible to EfOM preloading than the microporous GAC. Furthermore, among the fourteen investigated PhACs, the negatively charged hydrophilic PhACs were generally subjected to a greater EfOM preloading impact. Copyright © 2016 Elsevier Ltd. All rights reserved.

Kidney-Sparing Methods for Extended-Field Intensity-Modulated Radiotherapy (EF-IMRT) in Cervical Carcinoma Treatment.

Science.gov (United States)

Kunogi, Hiroaki; Yamaguchi, Nanae; Terao, Yasuhisa; Sasai, Keisuke

2016-01-01

Coplanar extended-field intensity-modulated radiation therapy (EF-IMRT) targeting the whole-pelvic and para-aortic lymph nodes in patients with advanced cervical cancer results in impaired creatinine clearance. An improvement in renal function cannot be expected unless low-dose (approximately 10 Gy) kidney exposure is reduced. The dosimetric method should be considered during EF-IMRT planning to further reduce low-dose exposure to the kidneys. To assess the usefulness of non-coplanar EF-IMRT with kidney-avoiding beams to spare the kidneys during cervical carcinoma treatment in dosimetric analysis between non-coplanar and coplanar EF-IMRT, we compared the doses of the target organ and organs at risk, including the kidney, in 10 consecutive patients. To estimate the influence of EFRT on renal dysfunction, creatinine clearance values after treatment were also examined in 18 consecutive patients. Of these 18 patients, 10 patients who were included in the dosimetric analysis underwent extended field radiation therapy (EFRT) with concurrent chemotherapy, and eight patients underwent whole-pelvis radiation therapy with concurrent chemotherapy to treat cervical carcinoma between April 2012 and March 2015 at our institution. In the dosimetric analysis, non-coplanar EF-IMRT was effective at reducing low-dose (approximately 10 Gy) exposure to the kidneys, thus maintaining target coverage and sparing other organs at risk, such as the small bowel, rectum, and bladder, compared with coplanar EF-IMRT. Renal function in all 10 patients who underwent EFRT, including coplanar EF-IMRT (with kidney irradiation), was low after treatment, and differed significantly from that of the eight patients who underwent WPRT (no kidney irradiation) 6 months after the first day of treatment (P = 0.005). In conclusion, non-coplanar EF-IMRT should be considered in patients with advanced cervical cancer, particularly in patients with a long life expectancy or with pre-existing renal dysfunction.

The Latent Structure of Autistic Traits: A Taxometric, Latent Class and Latent Profile Analysis of the Adult Autism Spectrum Quotient

Science.gov (United States)

James, Richard J.; Dubey, Indu; Smith, Danielle; Ropar, Danielle; Tunney, Richard J.

2016-01-01

Autistic traits are widely thought to operate along a continuum. A taxometric analysis of Adult Autism Spectrum Quotient data was conducted to test this assumption, finding little support but identifying a high severity taxon. To understand this further, latent class and latent profile models were estimated that indicated the presence of six…

Translation elongation factor EF-Tu modulates filament formation of actin-like MreB protein in vitro.

Science.gov (United States)

Defeu Soufo, Hervé Joël; Reimold, Christian; Breddermann, Hannes; Mannherz, Hans G; Graumann, Peter L

2015-04-24

EF-Tu has been shown to interact with actin-like protein MreB and to affect its localization in Escherichia coli and in Bacillus subtilis cells. We have purified YFP-MreB in an active form, which forms filaments on glass slides in vitro and was active in dynamic light-scattering assays, polymerizing in milliseconds after addition of magnesium. Purified EF-Tu enhanced the amount of MreB filaments, as seen by sedimentation assays, the speed of filament formation and the length of MreB filaments in vitro. EF-Tu had the strongest impact on MreB filaments in a 1:1 ratio, and EF-Tu co-sedimented with MreB filaments, revealing a stoichiometric interaction between both proteins. This was supported by cross-linking assays where 1:1 species were well detectable. When expressed in E. coli cells, B. subtilis MreB formed filaments and induced the formation of co-localizing B. subtilis EF-Tu structures, indicating that MreB can direct the positioning of EF-Tu structures in a heterologous cell system. Fluorescence recovery after photobleaching analysis showed that MreB filaments have a higher turnover in B. subtilis cells than in E. coli cells, indicating different filament kinetics in homologous or heterologous cell systems. The data show that MreB can direct the localization of EF-Tu in vivo, which in turn positively affects the formation and dynamics of MreB filaments. Thus, EF-Tu is a modulator of the activity of a bacterial actin-like protein. Copyright © 2015. Published by Elsevier Ltd.

Effects of Exergame Play on EF in Children and Adolescents at a Summer Camp for Low Income Youth.

Science.gov (United States)

Flynn, Rachel M; Richert, Rebekah A; Staiano, Amanda E; Wartella, Ellen; Calvert, Sandra L

2014-01-01

Past research has suggested exergame play improves adolescents' executive function (EF) skills. EF change in 70 African American and Hispanic/Latino 10- to 16-year-olds participating in an inner-city summer camp was assessed following five 30-minute exergame play sessions. Children's EF scores improved from pre- to posttest, and factors related to this change were examined. The number of exergame sessions the participants attended predicted posttest scores. In addition, level of achievement during game play was related to EF scores. Finally, the children's level of enjoyment was not related to EF; however, frustration and boredom during game play were negatively related to EF. The findings are discussed in terms of their implications for the relationship between exergame play and cognitive benefits for adolescent players.

Energy-filtered Photoelectron Emission Microscopy (EF-PEEM) for imaging nanoelectronic materials

International Nuclear Information System (INIS)

Renault, Olivier; Chabli, Amal

2007-01-01

Photoelectron-Emission Microscopy (PEEM) is the most promising approach to photoemission-based (XPS, UPS) imaging techniques with high lateral resolution, typically below 100 nm. It has now reached its maturity with a new generation of instruments with energy-filtering capabilities. Therefore UPS and XPS imaging with energy-filtered PEEM (EF-PEEM) can be applied to technologically-relevant samples. UPS images with contrast in local work function, obtained with laboratory UV sources, are obtained in ultra-high vacuum environment with lateral resolutions better than 50 nm and sensitivies of 20 meV. XPS images with elemental and bonding state contrast can show up lateral resolution better than 200 nm with synchrotron excitation. In this paper, we present the principles and capabilities of EF-PEEM and nanospectroscopy. Then, we focus on an example of application to non-destructive work-function imaging of polycrystalline copper for advanced interconnects, where it is shown that EF-PEEM is an alternative to Kelvin probes

Latent-Trait Latent-Class Analysis of Self-Disclosure in the Work Environment

Science.gov (United States)

Maij-de Meij, Annette M.; Kelderman, Henk; van der Flier, Henk

2005-01-01

Based on the literature about self-disclosure, it was hypothesized that different groups of subjects differ in their pattern of self-disclosure with respect to different areas of social interaction. An extended latent-trait latent-class model was proposed to describe these general patterns of self-disclosure. The model was used to analyze the data…

Proteomic analysis of trichloroethylene-induced alterations in expression, distribution, and interactions of SET/TAF-Iα and two SET/TAF-Iα-binding proteins, eEF1A1 and eEF1A2, in hepatic L-02 cells

Energy Technology Data Exchange (ETDEWEB)

Hong, Wen-Xu; Yang, Liang; Chen, Moutong; Yang, Xifei; Ren, Xiaohu; Fang, Shisong; Ye, Jinbo; Huang, Haiyan; Peng, Chaoqiong; Zhou, Li; Huang, Xinfeng; Yang, Fan; Wu, Desheng; Zhuang, Zhixiong; Liu, Jianjun, E-mail: bio-research@hotmail.com

2012-09-01

Emerging evidence indicates that trichloroethylene (TCE) exposure causes severe hepatotoxicity. However, the mechanisms of TCE hepatotoxicity remain unclear. Recently, we reported that TCE exposure up-regulated the expression of the oncoprotein SET/TAF-Iα and SET knockdown attenuated TCE-induced cytotoxicity in hepatic L-02 cells. To decipher the function of SET/TAF-Iα and its contributions to TCE-induced hepatotoxicity, we employed a proteomic analysis of SET/TAF-Iα with tandem affinity purification to identify SET/TAF-Iα-binding proteins. We identified 42 novel Gene Ontology co-annotated SET/TAF-Iα-binding proteins. The identifications of two of these proteins (eEF1A1, elongation factor 1-alpha 1; eEF1A2, elongation factor 1-alpha 2) were confirmed by Western blot analysis and co-immunoprecipitation (Co-IP). Furthermore, we analyzed the effects of TCE on the expression, distribution and interactions of eEF1A1, eEF1A2 and SET in L-02 cells. Western blot analysis reveals a significant up-regulation of eEF1A1, eEF1A2 and two isoforms of SET, and immunocytochemical analysis reveals that eEF1A1 and SET is redistributed by TCE. SET is redistributed from the nucleus to the cytoplasm, while eFE1A1 is translocated from the cytoplasm to the nucleus. Moreover, we find by Co-IP that TCE exposure significantly increases the interaction of SET with eEF1A2. Our data not only provide insights into the physiological functions of SET/TAF-Iα and complement the SET interaction networks, but also demonstrate that TCE exposure induces alterations in the expression, distribution and interactions of SET and its binding partners. These alterations may constitute the mechanisms of TCE cytotoxicity. -- Highlights: ► Identify 62 SET/TAF-Iα-associated proteins in human L-02 cells ► Trichloroethylene (TCE) alters the interaction of SET with eEF1A1 and eEF1A2. ► TCE induces the translocation and up-regulation of SET. ► TCE induces the translocation and up-regulation of eEF1A.

Proteomic analysis of trichloroethylene-induced alterations in expression, distribution, and interactions of SET/TAF-Iα and two SET/TAF-Iα-binding proteins, eEF1A1 and eEF1A2, in hepatic L-02 cells

International Nuclear Information System (INIS)

Hong, Wen-Xu; Yang, Liang; Chen, Moutong; Yang, Xifei; Ren, Xiaohu; Fang, Shisong; Ye, Jinbo; Huang, Haiyan; Peng, Chaoqiong; Zhou, Li; Huang, Xinfeng; Yang, Fan; Wu, Desheng; Zhuang, Zhixiong; Liu, Jianjun

2012-01-01

Emerging evidence indicates that trichloroethylene (TCE) exposure causes severe hepatotoxicity. However, the mechanisms of TCE hepatotoxicity remain unclear. Recently, we reported that TCE exposure up-regulated the expression of the oncoprotein SET/TAF-Iα and SET knockdown attenuated TCE-induced cytotoxicity in hepatic L-02 cells. To decipher the function of SET/TAF-Iα and its contributions to TCE-induced hepatotoxicity, we employed a proteomic analysis of SET/TAF-Iα with tandem affinity purification to identify SET/TAF-Iα-binding proteins. We identified 42 novel Gene Ontology co-annotated SET/TAF-Iα-binding proteins. The identifications of two of these proteins (eEF1A1, elongation factor 1-alpha 1; eEF1A2, elongation factor 1-alpha 2) were confirmed by Western blot analysis and co-immunoprecipitation (Co-IP). Furthermore, we analyzed the effects of TCE on the expression, distribution and interactions of eEF1A1, eEF1A2 and SET in L-02 cells. Western blot analysis reveals a significant up-regulation of eEF1A1, eEF1A2 and two isoforms of SET, and immunocytochemical analysis reveals that eEF1A1 and SET is redistributed by TCE. SET is redistributed from the nucleus to the cytoplasm, while eFE1A1 is translocated from the cytoplasm to the nucleus. Moreover, we find by Co-IP that TCE exposure significantly increases the interaction of SET with eEF1A2. Our data not only provide insights into the physiological functions of SET/TAF-Iα and complement the SET interaction networks, but also demonstrate that TCE exposure induces alterations in the expression, distribution and interactions of SET and its binding partners. These alterations may constitute the mechanisms of TCE cytotoxicity. -- Highlights: ► Identify 62 SET/TAF-Iα-associated proteins in human L-02 cells ► Trichloroethylene (TCE) alters the interaction of SET with eEF1A1 and eEF1A2. ► TCE induces the translocation and up-regulation of SET. ► TCE induces the translocation and up-regulation of eEF1A.

Modeling Nonlinear Change via Latent Change and Latent Acceleration Frameworks: Examining Velocity and Acceleration of Growth Trajectories

Science.gov (United States)

Grimm, Kevin; Zhang, Zhiyong; Hamagami, Fumiaki; Mazzocco, Michele

2013-01-01

We propose the use of the latent change and latent acceleration frameworks for modeling nonlinear growth in structural equation models. Moving to these frameworks allows for the direct identification of "rates of change" and "acceleration" in latent growth curves--information available indirectly through traditional growth…

Micro-macro multilevel latent class models with multiple discrete individual-level variables

NARCIS (Netherlands)

Bennink, M.; Croon, M.A.; Kroon, B.; Vermunt, J.K.

2016-01-01

An existing micro-macro method for a single individual-level variable is extended to the multivariate situation by presenting two multilevel latent class models in which multiple discrete individual-level variables are used to explain a group-level outcome. As in the univariate case, the

The Fic protein Doc uses an inverted substrate to phosphorylate and inactivate EF-Tu.

Science.gov (United States)

Castro-Roa, Daniel; Garcia-Pino, Abel; De Gieter, Steven; van Nuland, Nico A J; Loris, Remy; Zenkin, Nikolay

2013-12-01

Fic proteins are ubiquitous in all of the domains of life and have critical roles in multiple cellular processes through AMPylation of (transfer of AMP to) target proteins. Doc from the doc-phd toxin-antitoxin module is a member of the Fic family and inhibits bacterial translation by an unknown mechanism. Here we show that, in contrast to having AMPylating activity, Doc is a new type of kinase that inhibits bacterial translation by phosphorylating the conserved threonine (Thr382) of the translation elongation factor EF-Tu, rendering EF-Tu unable to bind aminoacylated tRNAs. We provide evidence that EF-Tu phosphorylation diverged from AMPylation by antiparallel binding of the NTP relative to the catalytic residues of the conserved Fic catalytic core of Doc. The results bring insights into the mechanism and role of phosphorylation of EF-Tu in bacterial physiology as well as represent an example of the catalytic plasticity of enzymes and a mechanism for the evolution of new enzymatic activities.

Comparing the Measured and Latent Dark Triad: Are Three Measures Better than One?

Directory of Open Access Journals (Sweden)

Peter K. Jonason

2011-10-01

Full Text Available Could measurement level be a factor worth considering when studying the Dark Triad (i.e., narcissism, psychopathy, and Machiavellianism? In two studies (N  = 465, we compared the relative fit of two Dark Triad models: one that treats the three measures as separate-yet-related personality traits and another that treats the measures as tapping a single, latent construct. Mid-level personality traits, such as mate-retention strategies (Study 1 were best explained by a three-measure model, whereas the higher-order trait of sociosexuality (Study 2, were best explained by a single, latent-factor model. When considering mid-level measurement in personality, the three traits may provide independent effects for interpersonal relationships, whereas at the higher-order level, the three traits may function as a single entity relating to other higher-order traits. We suggest one should consider level of measurement between the predictor and criterion variables to better predict correlations among variables such as the Dark Triad. DOI: 10.2458/azu_jmmss.v2i1.12363

Longitudinal Research with Latent Variables

CERN Document Server

van Montfort, Kees; Satorra, Albert

2010-01-01

This book combines longitudinal research and latent variable research, i.e. it explains how longitudinal studies with objectives formulated in terms of latent variables should be carried out, with an emphasis on detailing how the methods are applied. Because longitudinal research with latent variables currently utilizes different approaches with different histories, different types of research questions, and different computer programs to perform the analysis, the book is divided into nine chapters. Starting from some background information about the specific approach, short history and the ma

75 FR 41894 - Wapakoneta Machine Company, Currently Known as EF Industrial Technologies, Inc., Wapakoneta, OH...

Science.gov (United States)

2010-07-19

... of early 2010, Wapakoneta Machine Company is currently known as EF Industrial Technologies, Inc. Some... Wapakoneta Machine Company, currently known as EF Industrial Technologies, Inc., Wapakoneta, Ohio became... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-73,211] Wapakoneta Machine...

Scan-rate and vacuum pressure dependence of the nucleation and growth dynamics in a spin-crossover single crystal: the role of latent heat.

Science.gov (United States)

Ridier, Karl; Rat, Sylvain; Salmon, Lionel; Nicolazzi, William; Molnár, Gábor; Bousseksou, Azzedine

2018-04-04

Using optical microscopy we studied the vacuum pressure dependence (0.1-1000 mbar) of the nucleation and growth dynamics of the thermally induced first-order spin transition in a single crystal of the spin-crossover compound [Fe(HB(tz)3)2] (tz = 1,2,4-triazol-1-yl). A crossover between a quasi-static hysteresis regime and a temperature-scan-rate-dependent kinetic regime is evidenced around 5 mbar due to the change of the heat exchange coupling between the crystal and its external environment. Remarkably, the absorption/dissipation rate of latent heat was identified as the key factor limiting the switching speed of the crystal.

Using existing questionnaires in latent class analysis

DEFF Research Database (Denmark)

Nielsen, Anne Molgaard; Vach, Werner; Kent, Peter

2016-01-01

BACKGROUND: Latent class analysis (LCA) is increasingly being used in health research, but optimal approaches to handling complex clinical data are unclear. One issue is that commonly used questionnaires are multidimensional, but expressed as summary scores. Using the example of low back pain (LBP......), the aim of this study was to explore and descriptively compare the application of LCA when using questionnaire summary scores and when using single items to subgrouping of patients based on multidimensional data. MATERIALS AND METHODS: Baseline data from 928 LBP patients in an observational study were...

Latent class analysis of the Yale-Brown Obsessive-Compulsive Scale symptoms in obsessive-compulsive disorder.

Science.gov (United States)

Delucchi, Kevin L; Katerberg, Hilga; Stewart, S Evelyn; Denys, Damiaan A J P; Lochner, Christine; Stack, Denise E; den Boer, Johan A; van Balkom, Anton J L M; Jenike, Michael A; Stein, Dan J; Cath, Danielle C; Mathews, Carol A

2011-01-01

Obsessive-compulsive disorder (OCD) is phenomenologically heterogeneous, and findings of underlying structure classification based on symptom grouping have been ambiguous to date. Variable-centered approaches, primarily factor analysis, have been used to identify homogeneous groups of symptoms; but person-centered latent methods have seen little use. This study was designed to uncover sets of homogeneous groupings within 1611 individuals with OCD based on symptoms. Latent class analysis models using 61 obsessive-compulsive symptoms collected from the Yale-Brown Obsessive-Compulsive Scale were fit. Relationships between latent class membership and treatment response, sex, symptom severity, and comorbid tic disorders were tested for relationship to class membership. Latent class analysis models of best fit yielded 3 classes. Classes differed only in frequency of symptom endorsement. Classes with higher symptom endorsement were associated with earlier age of onset, being male, higher Yale-Brown Obsessive-Compulsive Scale symptom severity scores, and comorbid tic disorders. There were no differences in treatment response between classes. These results provide support for the validity of a single underlying latent OCD construct, in addition to the distinct symptom factors identified previously via factor analyses. Copyright © 2011 Elsevier Inc. All rights reserved.

Proteomic analysis of trichloroethylene-induced alterations in expression, distribution, and interactions of SET/TAF-Iα and two SET/TAF-Iα-binding proteins, eEF1A1 and eEF1A2, in hepatic L-02 cells.

Science.gov (United States)

Hong, Wen-Xu; Yang, Liang; Chen, Moutong; Yang, Xifei; Ren, Xiaohu; Fang, Shisong; Ye, Jinbo; Huang, Haiyan; Peng, Chaoqiong; Zhou, Li; Huang, Xinfeng; Yang, Fan; Wu, Desheng; Zhuang, Zhixiong; Liu, Jianjun

2012-09-01

Emerging evidence indicates that trichloroethylene (TCE) exposure causes severe hepatotoxicity. However, the mechanisms of TCE hepatotoxicity remain unclear. Recently, we reported that TCE exposure up-regulated the expression of the oncoprotein SET/TAF-Iα and SET knockdown attenuated TCE-induced cytotoxicity in hepatic L-02 cells. To decipher the function of SET/TAF-Iα and its contributions to TCE-induced hepatotoxicity, we employed a proteomic analysis of SET/TAF-Iα with tandem affinity purification to identify SET/TAF-Iα-binding proteins. We identified 42 novel Gene Ontology co-annotated SET/TAF-Iα-binding proteins. The identifications of two of these proteins (eEF1A1, elongation factor 1-alpha 1; eEF1A2, elongation factor 1-alpha 2) were confirmed by Western blot analysis and co-immunoprecipitation (Co-IP). Furthermore, we analyzed the effects of TCE on the expression, distribution and interactions of eEF1A1, eEF1A2 and SET in L-02 cells. Western blot analysis reveals a significant up-regulation of eEF1A1, eEF1A2 and two isoforms of SET, and immunocytochemical analysis reveals that eEF1A1 and SET is redistributed by TCE. SET is redistributed from the nucleus to the cytoplasm, while eFE1A1 is translocated from the cytoplasm to the nucleus. Moreover, we find by Co-IP that TCE exposure significantly increases the interaction of SET with eEF1A2. Our data not only provide insights into the physiological functions of SET/TAF-Iα and complement the SET interaction networks, but also demonstrate that TCE exposure induces alterations in the expression, distribution and interactions of SET and its binding partners. These alterations may constitute the mechanisms of TCE cytotoxicity. Copyright © 2012 Elsevier Inc. All rights reserved.

Students' views on mathematics in single-sex and coed classrooms in Ghana

OpenAIRE

Bofah, Emmanuel Adu-Tutu; Hannula, Markku S.

2016-01-01

In this study, we investigated students’ views on themselves as learners of mathematics as a function of school-by-sex (N = 2034, MAge = 18.49, SDAge = 1.25; 12th-grade; 58.2% girls). Using latent variable Structural Equation Modeling (SEM), the measurement and structural equivalence as well as the equality of latent means of scores across single-sex and coed schools were tested. Findings regarding the latent mean differences revealed that girls in single-sex schools had significantly higher ...

Latent constructs of the autobiographical memory questionnaire: a recollection-belief model of autobiographical experience.

Science.gov (United States)

Fitzgerald, Joseph M; Broadbridge, Carissa L

2013-01-01

Many researchers employ single-item scales of subjective experiences such as imagery and confidence to assess autobiographical memory. We tested the hypothesis that four latent constructs, recollection, belief, impact, and rehearsal, account for the variance in commonly used scales across four different types of autobiographical memory: earliest childhood memory, cue word memory of personal experience, highly vivid memory, and most stressful memory. Participants rated each memory on scales hypothesised to be indicators of one of four latent constructs. Multi-group confirmatory factor analyses and structural analyses confirmed the similarity of the latent constructs of recollection, belief, impact, and rehearsal, as well as the similarity of the structural relationships among those constructs across memory type. The observed pattern of mean differences between the varieties of autobiographical experiences was consistent with prior research and theory in the study of autobiographical memory.

Regulation of eukaryotic elongation factor 1 alpha (eEF1A) by dynamic lysine methylation

DEFF Research Database (Denmark)

Jakobsson, Magnus E; Małecki, Jędrzej; Falnes, Pål Ø

2018-01-01

Lysine methylation is a frequent post-translational protein modification, which has been intensively studied in the case of histone proteins. Lysine methylations are also found on many non-histone proteins, and one prominent example is eukaryotic elongation factor 1 alpha (eEF1A). Besides its...... essential role in the protein synthesis machinery, a number of non-canonical functions have also been described for eEF1A, such as regulation of the actin cytoskeleton and the promotion of viral replication. The functional significance of the extensive lysine methylations on eEF1A, as well as the identity...

Executive function (EF) in dyslexia: examining an EF profile associated with dyslexia and comorbid dyslexia-ADHD and exploring the near and far transfer effects of EF training in dyslexia alone.

OpenAIRE

Doyle, Caoilainn

2017-01-01

Although there are several competing theories to explain dyslexia, no clear causal pathway has been established. Current theories also fail to address associated socio-emotional difficulties and high co-occurrence of dyslexia with ADHD. Executive function (EF), an umbrella term for a triad of high-level cognitive processes associated with pre-frontal brain regions – response inhibition (RI), working memory updating and switching, is a candidate factor for explaining the overlap between dyslex...

Translation elongation factor eEF1A2 is a potential oncoprotein that is overexpressed in two-thirds of breast tumours

International Nuclear Information System (INIS)

Tomlinson, Victoria AL; Newbery, Helen J; Wray, Naomi R; Jackson, Juliette; Larionov, Alexey; Miller, William R; Dixon, J Michael; Abbott, Catherine M

2005-01-01

The tissue-specific translation elongation factor eEF1A2 was recently shown to be a potential oncogene that is overexpressed in ovarian cancer. Although there is no direct evidence for an involvement of eEF1A2 in breast cancer, the genomic region to which EEF1A2 maps, 20q13, is frequently amplified in breast tumours. We therefore sought to establish whether eEF1A2 expression might be upregulated in breast cancer. eEF1A2 is highly similar (98%) to the near-ubiquitously expressed eEF1A1 (formerly known as EF1-α) making analysis with commercial antibodies difficult. We have developed specific anti-eEF1A2 antibodies and used them in immunohistochemical analyses of tumour samples. We report the novel finding that although eEF1A2 is barely detectable in normal breast it is moderately to strongly expressed in two-thirds of breast tumours. This overexpression is strongly associated with estrogen receptor positivity. eEF1A2 should be considered as a putative oncogene in breast cancer that may be a useful diagnostic marker and therapeutic target for a high proportion of breast tumours. The oncogenicity of eEF1A2 may be related to its role in protein synthesis or to its potential non-canonical functions in cytoskeletal remodelling or apoptosis

Fatal and serious road crashes involving young New Zealand drivers: a latent class clustering approach

DEFF Research Database (Denmark)

Weiss, Harold B.; Kaplan, Sigal; Prato, Carlo Giacomo

2016-01-01

, infrastructure characteristics, environmental conditions, demographic characteristics, driving behaviour, and pre-crash manoeuvres. The analysis yielded 15 and 8 latent classes of, respectively, single-vehicle and multi-vehicle crashes, and average posterior probabilities measured the odds of correct...

Do executive functions explain the covariance between internalizing and externalizing behaviors?

Science.gov (United States)

Hatoum, Alexander S; Rhee, Soo Hyun; Corley, Robin P; Hewitt, John K; Friedman, Naomi P

2017-11-16

This study examined whether executive functions (EFs) might be common features of internalizing and externalizing behavior problems across development. We examined relations between three EF latent variables (a common EF factor and factors specific to updating working memory and shifting sets), constructed from nine laboratory tasks administered at age 17, to latent growth intercept (capturing stability) and slope (capturing change) factors of teacher- and parent-reported internalizing and externalizing behaviors in 885 individual twins aged 7 to 16 years. We then estimated the proportion of intercept-intercept and slope-slope correlations predicted by EF as well as the association between EFs and a common psychopathology factor (P factor) estimated from all 9 years of internalizing and externalizing measures. Common EF was negatively associated with the intercepts of teacher-rated internalizing and externalizing behavior in males, and explained 32% of their covariance; in the P factor model, common EF was associated with the P factor in males. Shifting-specific was positively associated with the externalizing slope across sex. EFs did not explain covariation between parent-rated behaviors. These results suggest that EFs are associated with stable problem behavior variation, explain small proportions of covariance, and are a risk factor that that may depend on gender.

Translation elongation factor eEF1A2 is a potential oncoprotein that is overexpressed in two-thirds of breast tumours

Directory of Open Access Journals (Sweden)

Miller William R

2005-09-01

Full Text Available Abstract Background The tissue-specific translation elongation factor eEF1A2 was recently shown to be a potential oncogene that is overexpressed in ovarian cancer. Although there is no direct evidence for an involvement of eEF1A2 in breast cancer, the genomic region to which EEF1A2 maps, 20q13, is frequently amplified in breast tumours. We therefore sought to establish whether eEF1A2 expression might be upregulated in breast cancer. Methods eEF1A2 is highly similar (98% to the near-ubiquitously expressed eEF1A1 (formerly known as EF1-α making analysis with commercial antibodies difficult. We have developed specific anti-eEF1A2 antibodies and used them in immunohistochemical analyses of tumour samples. We report the novel finding that although eEF1A2 is barely detectable in normal breast it is moderately to strongly expressed in two-thirds of breast tumours. This overexpression is strongly associated with estrogen receptor positivity. Conclusion eEF1A2 should be considered as a putative oncogene in breast cancer that may be a useful diagnostic marker and therapeutic target for a high proportion of breast tumours. The oncogenicity of eEF1A2 may be related to its role in protein synthesis or to its potential non-canonical functions in cytoskeletal remodelling or apoptosis.

Bacterial elongation factors EF-Tu, their mutants, chimeric forms, and domains: isolation and purification

Czech Academy of Sciences Publication Activity Database

Jonák, Jiří

2007-01-01

Roč. 849, 1-2 (2007), s. 141-153 ISSN 1570-0232 R&D Projects: GA AV ČR IAA5052206; GA AV ČR KJB500520503; GA MŠk 2B06065 Institutional research plan: CEZ:AV0Z50520514 Keywords : bacterial elongation factors EF-Tu, , G-domain * recombinant EF-Tus * preparation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.935, year: 2007

Function and structure in phage Qbeta RNA replicase. Association of EF-Tu-Ts with the other enzyme subunits

DEFF Research Database (Denmark)

Blumenthal, T; Young, R A; Brown, S

1976-01-01

alters its quaternary structure: the EF-Tu-Ts cannot be covalently attached to the other enzyme subunits with bifunctional cross-linking reagents in the presence of RNA. This conformational change is not influenced by ionic strength. The addition of Qbeta RNA to the enzyme, does not result in the release...... for one another increases with increasing ionic strength. The enzyme is capable of initiation of RNA synthesis with synthetic templates only when in the low ionic strength conformation. Elongation of initiated polynucleotide chains is not affectedby ionic strength. Addition of Qbeta RNA to the enzyme also...... of EF-Tu-Ts from the other enzyme subunits: whereas free EF-Tu-Ts binds GDP independently of salt concentration, this binding by Qbeta replicase is sensitive to high ionic strength and remains so in the presence of Qbeta RNA. Furthermore, RNA does not allow the release of EF-Ts from EF-Tu by GTP...

Mammalian translation elongation factor eEF1A2: X-ray structure and new features of GDP/GTP exchange mechanism in higher eukaryotes.

Science.gov (United States)

Crepin, Thibaut; Shalak, Vyacheslav F; Yaremchuk, Anna D; Vlasenko, Dmytro O; McCarthy, Andrew; Negrutskii, Boris S; Tukalo, Michail A; El'skaya, Anna V

2014-11-10

Eukaryotic elongation factor eEF1A transits between the GTP- and GDP-bound conformations during the ribosomal polypeptide chain elongation. eEF1A*GTP establishes a complex with the aminoacyl-tRNA in the A site of the 80S ribosome. Correct codon-anticodon recognition triggers GTP hydrolysis, with subsequent dissociation of eEF1A*GDP from the ribosome. The structures of both the 'GTP'- and 'GDP'-bound conformations of eEF1A are unknown. Thus, the eEF1A-related ribosomal mechanisms were anticipated only by analogy with the bacterial homolog EF-Tu. Here, we report the first crystal structure of the mammalian eEF1A2*GDP complex which indicates major differences in the organization of the nucleotide-binding domain and intramolecular movements of eEF1A compared to EF-Tu. Our results explain the nucleotide exchange mechanism in the mammalian eEF1A and suggest that the first step of eEF1A*GDP dissociation from the 80S ribosome is the rotation of the nucleotide-binding domain observed after GTP hydrolysis. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Stability of latent class segments over time

DEFF Research Database (Denmark)

Mueller, Simone

2011-01-01

Dynamic stability, as the degree to which identified segments at a given time remain unchanged over time in terms of number, size and profile, is a desirable segment property which has received limited attention so far. This study addresses the question to what degree latent classes identified from...... logit model suggests significant changes in the price sensitivity and the utility from environmental claims between both experimental waves. A pooled scale adjusted latent class model is estimated jointly over both waves and the relative size of latent classes is compared across waves, resulting...... in significant differences in the size of two out of seven classes. These differences can largely be accounted for by the changes on the aggregated level. The relative size of latent classes is correlated at 0.52, suggesting a fair robustness. An ex-post characterisation of latent classes by behavioural...

Refreshing the Aged Latent Fingerprints with Ionizing Radiation Prior to the Cyanoacrylate Fuming Procedure: A Preliminary Study.

Science.gov (United States)

Ristova, Mimoza M; Radiceska, Pavlina; Bozinov, Igorco; Barandovski, Lambe

2016-05-01

One of the crucial factors determining the cyanoacrylate deposit quality over latent fingerprints appeared to be the extent of the humidity. This work focuses on the enhancement/refreshment of age-degraded latent fingerprints by irradiating the samples with UV, X-ray, or thermal neutrons prior to the cyanoacrylate (CA) fuming. Age degradation of latent fingerprints deposited on glass surfaces was examined through the decrease in the number of characteristic minutiae counts over time. A term "critical day" was introduced for the time at which the average number of identifiable minutiae definitions drops to one-half. Fingerprints older than their "critical day" were exposed to either UV, X-ray, or thermal neutrons. Identical reference samples were kept unexposed. All samples, both reference and irradiated, were developed during a single CA fuming procedure. Comparative latent fingerprint analysis showed that exposure to ionizing radiation enhances the CA fuming, yielding a 20-30% increase in average minutiae count. © 2015 American Academy of Forensic Sciences.

Is the mazEF toxin-antitoxin system responsible for vancomycin resistance in clinical isolates of Enterococcus faecalis?

Science.gov (United States)

Sadeghifard, Nourkhoda; Soheili, Sara; Sekawi, Zamberi; Ghafourian, Sobhan

2014-01-01

The current study was conducted to investigate the relationship between vancomycin-resistant Enterococcus faecalis (VRE) and the presence of mazEF toxin-antitoxin (TA) system, which may be useful as target for novel antimicrobial therapy concepts. The susceptibility of E. faecalis was determined by MIC, and the presence of the mazEF TA system was evaluated by PCR. Among 200 E. faecalis isolates 39.5% showed resistance to vancomycin (VRE), while 60.5% were susceptible strains (VSE). The mazEF TA system was positive in all VRE isolates (100%), but less prevalent (38/121, 31.4%) among the 121 VSE strains. In conclusion, our study demonstrated a positive relationship between the presence of vancomycin resistance and mazEF TA system. This observation may introduce therapeutic options against a novel antimicrobial target in enterococci.

Analysis of transgenic wheat (Triticum aestivum L.) harboring a maize (Zea mays L.) gene for plastid EF-Tu: segregation pattern, expression and effects of the transgene.

Science.gov (United States)

Fu, Jianming; Ristic, Zoran

2010-06-01

We previously reported that transgenic wheat (Triticum aestivum L.) carrying a maize (Zea mays L.) gene (Zmeftu1) for chloroplast protein synthesis elongation factor, EF-Tu, displays reduced thermal aggregation of leaf proteins, reduced injury to photosynthetic membranes (thylakoids), and enhanced rate of CO(2) fixation following exposure to heat stress (18 h at 45 degrees C) [Fu et al. in Plant Mol Biol 68:277-288, 2008]. In the current study, we investigated the segregation pattern and expression of the transgene Zmeftu1 and determined the grain yield of transgenic plants after exposure to a brief heat stress (18 h at 45 degrees C). We also assessed thermal aggregation of soluble leaf proteins in transgenic plants, testing the hypothesis that increased levels of EF-Tu will lead to a non-specific protection of leaf proteins against thermal aggregation. The transgenic wheat displayed a single-gene pattern of segregation of Zmeftu1. Zmeftu1 was expressed, and the transgenic plants synthesized and accumulated three anti-EF-Tu cross-reacting polypeptides of similar molecular mass but different pI, suggesting the possibility of posttranslational modification of this protein. The transgenic plants also showed better grain yield after exposure to heat stress compared with their non-transgenic counterparts. Soluble leaf proteins of various molecular masses displayed lower thermal aggregation in transgenic than in non-transgenic wheat. The results suggest that overexpression of chloroplast EF-Tu can be beneficial to wheat tolerance to heat stress. Moreover, the results also support the hypothesis that EF-Tu contributes to heat tolerance by acting as a molecular chaperone and protecting heat-labile proteins from thermal aggregation in a non-specific manner.

Functional role of EF-hands 3 and 4 in membrane-binding of KChIP1

Indian Academy of Sciences (India)

The aim of the present study is to explore whether membrane targeting of K+ channel-interacting protein 1 (KChIP1) is associated with its EF-hand motifs and varies with specific phospholipids. Truncated KChIP1, in which the EF-hands 3 and 4 were deleted, retained the -helix structure, indicating that the N-terminal half of ...

Pharmacokinetics and tissue distribution of enrofloxacin after single intramuscular injection in Pacific white shrimp.

Science.gov (United States)

Fang, X; Zhou, J; Liu, X

2018-02-01

The pharmacokinetic properties and tissue distribution of enrofloxacin (EF) were investigated after single intramuscular (i.m.) dose of 10 mg/kg body weight (b.w.) in Pacific white shrimp at 22 to 25°C. EF and its metabolite ciprofloxacin (CF) were determined by high-performance liquid chromatography. After i.m. administration, EF was absorbed quickly, and the peak of EF concentration (C max ) reached at first time point in hemolymph. The volume of distribution V d(area) of EF was 3.84 L/kg, indicating that the distribution of EF was good. The area under the concentration-time curve (AUC) of EF was 90.1 and 274.2 μg hr/ml in muscle and hepatopancreas, respectively, which was higher than 75.8 μg hr/ml in hemolymph. The EF elimination was slow in muscle and hepatopancreas with the half-life (T 1/2β ) of 52.3 and 75.8 hr, respectively. CF, the mainly metabolite of EF, was detected in hemolymph, muscle and hepatopancreas. The C max was 0.030, 0.013 and 0.218 μg/ml, respectively. Based on a minimum inhibitory concentration (MIC) of 0.006-0.032 μg/ml for susceptible strains, EF i.m. injected at a dose 10 mg/kg could be efficacious against common pathogenic bacteria of Pacific white shrimp. © 2017 John Wiley & Sons Ltd.

Simulation and analysis of single-ribosome translation

International Nuclear Information System (INIS)

Tinoco, Ignacio Jr; Wen, Jin-Der

2009-01-01

In the cell, proteins are synthesized by ribosomes in a multi-step process called translation. The ribosome translocates along the messenger RNA to read the codons that encode the amino acid sequence of a protein. Elongation factors, including EF-G and EF-Tu, are used to catalyze the process. Recently, we have shown that translation can be followed at the single-molecule level using optical tweezers; this technique allows us to study the kinetics of translation by measuring the lifetime the ribosome spends at each codon. Here, we analyze the data from single-molecule experiments and fit the data with simple kinetic models. We also simulate the translation kinetics based on a multi-step mechanism from ensemble kinetic measurements. The mean lifetimes from the simulation were consistent with our experimental single-molecule measurements. We found that the calculated lifetime distributions were fit in general by equations with up to five rate-determining steps. Two rate-determining steps were only obtained at low concentrations of elongation factors. These analyses can be used to design new single-molecule experiments to better understand the kinetics and mechanism of translation

The Influence of the Toxin/Antitoxin mazEF on Growth and Survival of Listeria monocytogenes under Stress.

Science.gov (United States)

Curtis, Thomas D; Takeuchi, Ippei; Gram, Lone; Knudsen, Gitte M

2017-01-13

A major factor in the resilience of Listeria monocytogenes is the alternative sigma factor B (σ B ). Type II Toxin/Antitoxin (TA) systems are also known to have a role in the bacterial stress response upon activation via the ClpP or Lon proteases. Directly upstream of the σ B operon in L. monocytogenes is the TA system mazEF , which can cleave mRNA at UACMU sites. In this study, we showed that the mazEF TA locus does not affect the level of persister formation during treatment with antibiotics in lethal doses, but exerts different effects according to the sub-inhibitory stress added. Growth of a Δ mazEF mutant was enhanced relative to the wildtype in the presence of sub-inhibitory norfloxacin and at 42 °C, but was decreased when challenged with ampicillin and gentamicin. In contrast to studies in Staphylococcus aureus , we found that the mazEF locus did not affect transcription of genes within the σ B operon, but MazEF effected the expression of the σ B -dependent genes opuCA and lmo0880 , with a 0.22 and 0.05 fold change, respectively, compared to the wildtype under sub-inhibitory norfloxacin conditions. How exactly this system operates remains an open question, however, our data indicates it is not analogous to the system of S. aureus , suggesting a novel mode of action for MazEF in L. monocytogenes.

Decoding the biosynthesis and function of diphthamide, an enigmatic modification of translation elongation factor 2 (EF2

Directory of Open Access Journals (Sweden)

Raffael Schaffrath

2014-05-01

Full Text Available Diphthamide is a highly conserved modification of archaeal and eukaryal translation elongation factor 2 (EF2 and yet why cells need EF2 to contain diphthamide is unclear. In yeast, the first steps of diphthamide synthesis and the genes (DPH1-DPH5 required to form the intermediate diphthine are well-documented. However, the last step, amidadation of diphthine to diphthamide, had largely been ill-defined. Remarkably, through mining genome-wide synthetic gene array (SGA and chemical genomics databases, recent studies by Uthman et al. [PLoS Genetics (2013 9, e1003334] and Su et al. [Proc. Natl. Acad. Sci. USA (2012 109, 19983-19987] have identified two more diphthamide players, DPH6 and DPH7. Consistent with roles in the amidation step, dph6 and dph7 deletion strains fail to complete diphthamide synthesis and accumulate diphthine-modified EF2. In contrast to Dph6, the catalytically relevant amidase, Dph7 appears to be regulatory. As shown by Uthman et al., it promotes dissociation of diphthine synthase (Dph5 from EF2, allowing diphthine amidation by Dph6 to occur and thereby coupling diphthine synthesis to the terminal step in the pathway. Remarkably, the study by Uthman et al. suggests that Dph5 has a novel role as an EF2 inhibitor that affects cell growth when diphthamide synthesis is blocked or incomplete and, importantly, shows that diphthamide promotes the accuracy of EF2 performance during translation.

Biomarkers of latent TB infection

DEFF Research Database (Denmark)

Ruhwald, Morten; Ravn, Pernille

2009-01-01

For the last 100 years, the tuberculin skin test (TST) has been the only diagnostic tool available for latent TB infection (LTBI) and no biomarker per se is available to diagnose the presence of LTBI. With the introduction of M. tuberculosis-specific IFN-gamma release assays (IGRAs), a new area...... of in vitro immunodiagnostic tests for LTBI based on biomarker readout has become a reality. In this review, we discuss existing evidence on the clinical usefulness of IGRAs and the indefinite number of potential new biomarkers that can be used to improve diagnosis of latent TB infection. We also present...... early data suggesting that the monocyte-derived chemokine inducible protein-10 may be useful as a novel biomarker for the immunodiagnosis of latent TB infection....

Identification of a Novel EF-Loop in the N-terminus of TRPM2 Channel Involved in Calcium Sensitivity

Directory of Open Access Journals (Sweden)

Yuhuan Luo

2018-06-01

Full Text Available As an oxidative stress sensor, transient receptor potential melastatin 2 (TRPM2 channel is involved in many physiological and pathological processes including warmth sensing, ischemia injury, inflammatory diseases and diabetes. Intracellular calcium is critical for TRPM2 channel activation and the IQ-like motif in the N-terminus has been shown to be important by mediating calmodulin binding. Sequence analysis predicted two potential EF-loops in the N-terminus of TRPM2. Site-directed mutagenesis combining with functional assay showed that substitution with alanine of several residues, most of which are conserved in the typical EF-loop, including D267, D278, D288, and E298 dramatically reduced TRPM2 channel currents. By further changing the charges or side chain length of these conserved residues, our results indicate that the negative charge of D267 and the side chain length of D278 are critical for calcium-induced TRPM2 channel activation. G272I mutation also dramatically reduced the channel currents, suggesting that this site is critical for calcium-induced TRPM2 channel activation. Furthermore, D267A mutant dramatically reduced the currents induced by calcium alone compared with that by ADPR, indicating that D267 residue in D267–D278 motif is the most important site for calcium sensitivity of TRPM2. In addition, inside-out recordings showed that mutations at D267, G272, D278, and E298 had no effect on single-channel conductance. Taken together, our data indicate that D267–D278 motif in the N-terminus as a novel EF-loop is critical for calcium-induced TRPM2 channel activation.

UNSOLVED AND LATENT CRIME: DIFFERENCES AND SIMILARITIES

Directory of Open Access Journals (Sweden)

Mikhail Kleymenov

2017-01-01

Full Text Available УДК 343Purpose of the article is to study the specific legal and informational nature of the unsolved crime in comparison with the phenomenon of delinquency, special study and analysis to improve the efficiency of law enforcement.Methods of research are abstract-logical, systematic, statistical, study of documents. The main results of research. Unsolved crime has specific legal, statistical and informational na-ture as the crime phenomenon, which is expressed in cumulative statistical population of unsolved crimes. An array of unsolved crimes is the sum of the number of acts, things of which is suspended and not terminated. The fault of the perpetrator in these cases is not proven, they are not considered by the court, it is not a conviction. Unsolved crime must be registered. Latent crime has a different informational nature. The main symptom of latent crimes is the uncertainty for the subjects of law enforcement, which delegated functions of identification, registration and accounting. Latent crime is not recorded. At the same time, there is a "border" area between the latent and unsolved crimes, which includes covered from the account of the crime. In modern Russia the majority of crimes covered from accounting by passing the decision about refusal in excitation of criminal case. Unsolved crime on their criminogenic consequences represents a significant danger to the public is higher compared to latent crime.It is conducted in the article a special analysis of the differences and similarities in the unsolved latent crime for the first time in criminological literature.The analysis proves the need for radical changes in the current Russian assessment of the state of crime and law enforcement to solve crimes. The article argues that an unsolved crime is a separate and, in contrast to latent crime, poorly understood phenomenon. However unsolved latent crime and have common features and areas of interaction.

Latent geometry of bipartite networks

Science.gov (United States)

Kitsak, Maksim; Papadopoulos, Fragkiskos; Krioukov, Dmitri

2017-03-01

Despite the abundance of bipartite networked systems, their organizing principles are less studied compared to unipartite networks. Bipartite networks are often analyzed after projecting them onto one of the two sets of nodes. As a result of the projection, nodes of the same set are linked together if they have at least one neighbor in common in the bipartite network. Even though these projections allow one to study bipartite networks using tools developed for unipartite networks, one-mode projections lead to significant loss of information and artificial inflation of the projected network with fully connected subgraphs. Here we pursue a different approach for analyzing bipartite systems that is based on the observation that such systems have a latent metric structure: network nodes are points in a latent metric space, while connections are more likely to form between nodes separated by shorter distances. This approach has been developed for unipartite networks, and relatively little is known about its applicability to bipartite systems. Here, we fully analyze a simple latent-geometric model of bipartite networks and show that this model explains the peculiar structural properties of many real bipartite systems, including the distributions of common neighbors and bipartite clustering. We also analyze the geometric information loss in one-mode projections in this model and propose an efficient method to infer the latent pairwise distances between nodes. Uncovering the latent geometry underlying real bipartite networks can find applications in diverse domains, ranging from constructing efficient recommender systems to understanding cell metabolism.

Pathways of early fatherhood, marriage, and employment: a latent class growth analysis.

Science.gov (United States)

Dariotis, Jacinda K; Pleck, Joseph H; Astone, Nan M; Sonenstein, Freya L

2011-05-01

In the National Longitudinal Survey of Youth 1979 (NLSY79), young fathers include heterogeneous subgroups with varying early life pathways in terms of fatherhood timing, the timing of first marriage, and holding full-time employment. Using latent class growth analysis with 10 observations between ages 18 and 37, we derived five latent classes with median ages of first fatherhood below the cohort median (26.4), constituting distinct early fatherhood pathways representing 32.4% of NLSY men: (A) Young Married Fathers, (B) Teen Married Fathers, (C) Young Underemployed Married Fathers, (D) Young Underemployed Single Fathers, and (E) Young Later-Marrying Fathers. A sixth latent class of men who become fathers around the cohort median, following full-time employment and marriage (On-Time On-Sequence Fathers), is the comparison group. With sociodemographic background controlled, all early fatherhood pathways show disadvantage in at least some later-life circumstances (earnings, educational attainment, marital status, and incarceration). The extent of disadvantage is greater when early fatherhood occurs at relatively younger ages (before age 20), occurs outside marriage, or occurs outside full-time employment. The relative disadvantage associated with early fatherhood, unlike early motherhood, increases over the life course.

Latent class analysis derived subgroups of low back pain patients - do they have prognostic capacity?

DEFF Research Database (Denmark)

Mølgaard Nielsen, Anne; Hestbaek, Lise; Vach, Werner

2017-01-01

. Previously, we developed two novel suggestions for subgrouping patients with low back pain based on Latent Class Analysis of patient baseline characteristics (patient history and physical examination), which resulted in 7 subgroups when using a single-stage analysis, and 9 subgroups when using a two...

Latent hardening size effect in small-scale plasticity

Science.gov (United States)

Bardella, Lorenzo; Segurado, Javier; Panteghini, Andrea; Llorca, Javier

2013-07-01

We aim at understanding the multislip behaviour of metals subject to irreversible deformations at small-scales. By focusing on the simple shear of a constrained single-crystal strip, we show that discrete Dislocation Dynamics (DD) simulations predict a strong latent hardening size effect, with smaller being stronger in the range [1.5 µm, 6 µm] for the strip height. We attempt to represent the DD pseudo-experimental results by developing a flow theory of Strain Gradient Crystal Plasticity (SGCP), involving both energetic and dissipative higher-order terms and, as a main novelty, a strain gradient extension of the conventional latent hardening. In order to discuss the capability of the SGCP theory proposed, we implement it into a Finite Element (FE) code and set its material parameters on the basis of the DD results. The SGCP FE code is specifically developed for the boundary value problem under study so that we can implement a fully implicit (Backward Euler) consistent algorithm. Special emphasis is placed on the discussion of the role of the material length scales involved in the SGCP model, from both the mechanical and numerical points of view.

Latent hardening size effect in small-scale plasticity

International Nuclear Information System (INIS)

Bardella, Lorenzo; Panteghini, Andrea; Segurado, Javier; Llorca, Javier

2013-01-01

We aim at understanding the multislip behaviour of metals subject to irreversible deformations at small-scales. By focusing on the simple shear of a constrained single-crystal strip, we show that discrete Dislocation Dynamics (DD) simulations predict a strong latent hardening size effect, with smaller being stronger in the range [1.5 µm, 6 µm] for the strip height. We attempt to represent the DD pseudo-experimental results by developing a flow theory of Strain Gradient Crystal Plasticity (SGCP), involving both energetic and dissipative higher-order terms and, as a main novelty, a strain gradient extension of the conventional latent hardening. In order to discuss the capability of the SGCP theory proposed, we implement it into a Finite Element (FE) code and set its material parameters on the basis of the DD results. The SGCP FE code is specifically developed for the boundary value problem under study so that we can implement a fully implicit (Backward Euler) consistent algorithm. Special emphasis is placed on the discussion of the role of the material length scales involved in the SGCP model, from both the mechanical and numerical points of view. (paper)

How preschool executive functioning predicts several aspects of math achievement in Grades 1 and 3: A longitudinal study.

Science.gov (United States)

Viterbori, Paola; Usai, M Carmen; Traverso, Laura; De Franchis, Valentina

2015-12-01

This longitudinal study analyzes whether selected components of executive function (EF) measured during the preschool period predict several indices of math achievement in primary school. Six EF measures were assessed in a sample of 5-year-old children (N = 175). The math achievement of the same children was then tested in Grades 1 and 3 using both a composite math score and three single indices of written calculation, arithmetical facts, and problem solving. Using previous results obtained from the same sample of children, a confirmatory factor analysis examining the latent EF structure in kindergarten indicated that a two-factor model provided the best fit for the data. In this model, inhibition and working memory (WM)-flexibility were separate dimensions. A full structural equation model was then used to test the hypothesis that math achievement (the composite math score and single math scores) in Grades 1 and 3 could be explained by the two EF components comprising the kindergarten model. The results indicate that the WM-flexibility component measured during the preschool period substantially predicts mathematical achievement, especially in Grade 3. The math composite scores were predicted by the WM-flexibility factor at both grade levels. In Grade 3, both problem solving and arithmetical facts were predicted by the WM-flexibility component. The results empirically support interventions that target EF as an important component of early childhood mathematics education. Copyright © 2015 Elsevier Inc. All rights reserved.

Data on the interexaminer variation of minutia markup on latent fingerprints.

Science.gov (United States)

Ulery, Bradford T; Hicklin, R Austin; Roberts, Maria Antonia; Buscaglia, JoAnn

2016-09-01

The data in this article supports the research paper entitled "Interexaminer variation of minutia markup on latent fingerprints" [1]. The data in this article describes the variability in minutia markup during both analysis of the latents and comparison between latents and exemplars. The data was collected in the "White Box Latent Print Examiner Study," in which each of 170 volunteer latent print examiners provided detailed markup documenting their examinations of latent-exemplar pairs of prints randomly assigned from a pool of 320 pairs. Each examiner examined 22 latent-exemplar pairs; an average of 12 examiners marked each latent.

A flexible latent class approach to estimating test-score reliability

NARCIS (Netherlands)

van der Palm, D.W.; van der Ark, L.A.; Sijtsma, K.

2014-01-01

The latent class reliability coefficient (LCRC) is improved by using the divisive latent class model instead of the unrestricted latent class model. This results in the divisive latent class reliability coefficient (DLCRC), which unlike LCRC avoids making subjective decisions about the best solution

The mazEF toxin-antitoxin system as a novel antibacterial target in Acinetobacter baumannii.

Science.gov (United States)

Ghafourian, Sobhan; Good, Liam; Sekawi, Zamberi; Hamat, Rukman Awang; Soheili, Sara; Sadeghifard, Nourkhoda; Neela, Vasanthakumari

2014-07-01

Although analysis of toxin-antitoxin (TA) systems can be instructive, to date, there is no information on the prevalence and identity of TA systems based on a large panel of Acinetobacter baumannii clinical isolates. The aim of the current study was to screen for functional TA systems among clinical isolates of A. baumannii and to identify the systems' locations. For this purpose, we screened 85 A. baumannii isolates collected from different clinical sources for the presence of the mazEF, relBE and higBA TA genes. The results revealed that the genes coding for the mazEF TA system were commonly present in all clinical isolates of A. baumannii. Reverse transcriptase-polymerase chain reaction analysis showed that transcripts were produced in the clinical isolates. Our findings showed that TA genes are prevalent, harboured by chromosomes and transcribed within A. baumannii. Hence, activation of the toxin proteins in the mazEF TA system should be investigated further as an effective antibacterial strategy against this bacterium.

On the explaining-away phenomenon in multivariate latent variable models.

Science.gov (United States)

van Rijn, Peter; Rijmen, Frank

2015-02-01

Many probabilistic models for psychological and educational measurements contain latent variables. Well-known examples are factor analysis, item response theory, and latent class model families. We discuss what is referred to as the 'explaining-away' phenomenon in the context of such latent variable models. This phenomenon can occur when multiple latent variables are related to the same observed variable, and can elicit seemingly counterintuitive conditional dependencies between latent variables given observed variables. We illustrate the implications of explaining away for a number of well-known latent variable models by using both theoretical and real data examples. © 2014 The British Psychological Society.

The SOS response is permitted in Escherichia coli strains deficient in the expression of the mazEF pathway.

Science.gov (United States)

Kalderon, Ziva; Kumar, Sathish; Engelberg-Kulka, Hanna

2014-01-01

The Escherichia coli (E. coli) SOS response is the largest, most complex, and best characterized bacterial network induced by DNA damage. It is controlled by a complex network involving the RecA and LexA proteins. We have previously shown that the SOS response to DNA damage is inhibited by various elements involved in the expression of the E. coli toxin-antitoxin mazEF pathway. Since the mazEF module is present on the chromosomes of most E. coli strains, here we asked: Why is the SOS response found in so many E. coli strains? Is the mazEF module present but inactive in those strains? We examined three E. coli strains used for studies of the SOS response, strains AB1932, BW25113, and MG1655. We found that each of these strains is either missing or inhibiting one of several elements involved in the expression of the mazEF-mediated death pathway. Thus, the SOS response only takes place in E. coli cells in which one or more elements of the E. coli toxin-antitoxin module mazEF or its downstream pathway is not functioning.

Should researchers use single indicators, best indicators, or multiple indicators in structural equation models?

Directory of Open Access Journals (Sweden)

Hayduk Leslie A

2012-10-01

Full Text Available Abstract Background Structural equation modeling developed as a statistical melding of path analysis and factor analysis that obscured a fundamental tension between a factor preference for multiple indicators and path modeling’s openness to fewer indicators. Discussion Multiple indicators hamper theory by unnecessarily restricting the number of modeled latents. Using the few best indicators – possibly even the single best indicator of each latent – encourages development of theoretically sophisticated models. Additional latent variables permit stronger statistical control of potential confounders, and encourage detailed investigation of mediating causal mechanisms. Summary We recommend the use of the few best indicators. One or two indicators are often sufficient, but three indicators may occasionally be helpful. More than three indicators are rarely warranted because additional redundant indicators provide less research benefit than single indicators of additional latent variables. Scales created from multiple indicators can introduce additional problems, and are prone to being less desirable than either single or multiple indicators.

A neutron scattering study of the ternary complex EF-Tu.GTP-valyl-tRNAVal1A

DEFF Research Database (Denmark)

Österberg, R.; Elias, P.; Kjems, Jørgen

1986-01-01

The complex formation between elongation factor Tu (EF-Tu), GTP, and valyl-tRNAVal1A has been investigated in a hepes buffer of "pH" 7.4 and 0.2 M ionic strength using the small-angle neutron scattering method at concentrations of D2O where EF-Tu (42% D2O) and tRNA (71% D2O) are successively...

Evaluation of {sup 18}F-BCPP-EF for mitochondrial complex 1 imaging in the brain of conscious monkeys using PET

Energy Technology Data Exchange (ETDEWEB)

Tsukada, Hideo; Ohba, Hiroyuki; Kanazawa, Masakatsu; Kakiuchi, Takeharu; Harada, Norihiro [Hamamatsu Photonics K.K., Central Research Laboratory, Hamamatsu, Shizuoka (Japan)

2014-04-15

We have reported on the development of a novel PET probe, {sup 18}F-2-tert-butyl-4-chloro-5-{6-[2-(2-fluoroethoxy)-ethoxy] -pyridin-3-ylmethoxy}-2H-pyridazin-3-one ({sup 18}F-BCPP-EF), for quantitative imaging of mitochondrial complex 1 (MC-1) activity in the brain of the living rat. For clinical application in humans, translational research in the monkey was conducted. PET measurements with {sup 18}F-BCPP-EF were performed in young and old monkeys (Macaca mulatta) in a conscious state with arterial blood sampling. The binding specificity of {sup 18}F-BCPP-EF was evaluated with rotenone, a specific MC-1 inhibitor, in young animals. The binding (total distribution volume, V{sub T}) of {sup 18}F-BCPP-EF was calculated using Logan graphical analysis, and one-tissue compartment model (1-TC) and two-tissue compartment model (2-TC) analyses using a metabolite-corrected plasma input function. F-BCPP-EF was rapidly taken up into the brain just after intravenous injection, peaked between 10 and 20 min after injection, and was then gradually eliminated. The 2-TC analysis provided a better fit than the 1-TC analysis, and the V{sub T} values from the 2-TC analysis correlated well with those from the Logan plot. With predosing with rotenone, {sup 18}F-BCPP-EF showed a higher uptake peak in the brain, followed by more rapid elimination thereafter than in the vehicle condition, resulting in significant reductions in 2-TC V{sub T} values in all regions. In old animals, the kinetics of {sup 18}F-BCPP-EF were slightly slower with lower peak levels than in young animals, resulting age-related reductions in {sup 18}F-BCPP-EF binding in all brain regions. The present study demonstrated that {sup 18}F-BCPP-EF may be a potential PET probe for quantitative imaging MC-1 activity in the living brain using PET. (orig.)

Extraction of latent images from printed media

Science.gov (United States)

Sergeyev, Vladislav; Fedoseev, Victor

2015-12-01

In this paper we propose an automatic technology for extraction of latent images from printed media such as documents, banknotes, financial securities, etc. This technology includes image processing by adaptively constructed Gabor filter bank for obtaining feature images, as well as subsequent stages of feature selection, grouping and multicomponent segmentation. The main advantage of the proposed technique is versatility: it allows to extract latent images made by different texture variations. Experimental results showing performance of the method over another known system for latent image extraction are given.

Evidence of MexT-independent overexpression of MexEF-OprN multidrug efflux pump of Pseudomonas aeruginosa in presence of metabolic stress.

Directory of Open Access Journals (Sweden)

Ayush Kumar

Full Text Available The Pseudomonas aeruginosa MexEF-OprN efflux pump confers resistance to clinically significant antibiotics. Regulation of mexEF-oprN operon expression is multifaceted with the MexT activator being one of the most prominent regulatory proteins.We have exploited the impaired metabolic fitness of a P. aeruginosa mutant strain lacking several efflux pump of the resistance nodulation cell division superfamily and the TolC homolog OpmH, and isolated derivatives (large colony variants that regained fitness by incubation on nutrient-rich medium in the absence of antibiotics. Although the mexEF-oprN operon is uninducible in this mutant due to a 8-bp mexT insertion present in some P. aeruginosa PAO1 strains, the large colony variants expressed high levels of MexEF-OprN. Unlike large colony variants obtained after plating on antibiotic containing medium which expressed mexEF-oprN in a MexT-dependent fashion as evidenced by clean excision of the 8-bp insertion from mexT, mexEF-oprN expression was MexT-independent in the large colony variants obtained by plating on LB alone since the mexT gene remained inactivated. A search for possible regulators of mexEF-oprN expression using transposon mutagenesis and genomic library expression approaches yielded several candidates but proved inconclusive.Our results show that antibiotic and metabolic stress lead to up-regulation of MexEF-OprN expression via different mechanisms and that MexEF-OprN does not only extrude antimicrobials but rather serves other important metabolic functions.

Safety aspects of the emergency filtration system (EFS) for NRU reactor

International Nuclear Information System (INIS)

Hickey, D.L.; Lounsbury, R.I.

1990-01-01

A description of the NRU emergency filter system (EFS) is presented, including operation, testing and hazards. Operation of the NRU EFS reduces the dose to the thyroid for members of the public and site personnel by a factor of 100. The calculated thyroid doses for off-site and on-site locations for the current system configuration are 91 and 160 mSv, respectively. An unavailability analysis was performed on the control system which recognized subtle problems in the current system. Modifications to the system result in a system unavailability of 2.0 E-3. The thyroid risk analysis revealed that these improvements in system availability result in risk reduction by approximately a factor of three. Improvements beyond the availability analysis recommendations do not result in substantial risk benefit for members of the public or on-site personnel

Fitting Latent Cluster Models for Networks with latentnet

Directory of Open Access Journals (Sweden)

Pavel N. Krivitsky

2007-12-01

Full Text Available latentnet is a package to fit and evaluate statistical latent position and cluster models for networks. Hoff, Raftery, and Handcock (2002 suggested an approach to modeling networks based on positing the existence of an latent space of characteristics of the actors. Relationships form as a function of distances between these characteristics as well as functions of observed dyadic level covariates. In latentnet social distances are represented in a Euclidean space. It also includes a variant of the extension of the latent position model to allow for clustering of the positions developed in Handcock, Raftery, and Tantrum (2007.The package implements Bayesian inference for the models based on an Markov chain Monte Carlo algorithm. It can also compute maximum likelihood estimates for the latent position model and a two-stage maximum likelihood method for the latent position cluster model. For latent position cluster models, the package provides a Bayesian way of assessing how many groups there are, and thus whether or not there is any clustering (since if the preferred number of groups is 1, there is little evidence for clustering. It also estimates which cluster each actor belongs to. These estimates are probabilistic, and provide the probability of each actor belonging to each cluster. It computes four types of point estimates for the coefficients and positions: maximum likelihood estimate, posterior mean, posterior mode and the estimator which minimizes Kullback-Leibler divergence from the posterior. You can assess the goodness-of-fit of the model via posterior predictive checks. It has a function to simulate networks from a latent position or latent position cluster model.

Early Executive Function at Age Two Predicts Emergent Mathematics and Literacy at Age Five.

Science.gov (United States)

Mulder, Hanna; Verhagen, Josje; Van der Ven, Sanne H G; Slot, Pauline L; Leseman, Paul P M

2017-01-01

Previous work has shown that individual differences in executive function (EF) are predictive of academic skills in preschoolers, kindergartners, and older children. Across studies, EF is a stronger predictor of emergent mathematics than literacy. However, research on EF in children below age three is scarce, and it is currently unknown whether EF, as assessed in toddlerhood, predicts emergent academic skills a few years later. This longitudinal study investigates whether early EF, assessed at two years, predicts (emergent) academic skills, at five years. It examines, furthermore, whether early EF is a significantly stronger predictor of emergent mathematics than of emergent literacy, as has been found in previous work on older children. A sample of 552 children was assessed on various EF and EF-precursor tasks at two years. At age five, these children performed several emergent mathematics and literacy tasks. Structural Equation Modeling was used to investigate the relationships between early EF and academic skills, modeled as latent factors. Results showed that early EF at age two was a significant and relatively strong predictor of both emergent mathematics and literacy at age five, after controlling for receptive vocabulary, parental education, and home language. Predictive relations were significantly stronger for mathematics than literacy, but only when a verbal short-term memory measure was left out as an indicator to the latent early EF construct. These findings show that individual differences in emergent academic skills just prior to entry into the formal education system can be traced back to individual differences in early EF in toddlerhood. In addition, these results highlight the importance of task selection when assessing early EF as a predictor of later outcomes, and call for further studies to elucidate the mechanisms through which individual differences in early EF and precursors to EF come about.

Early Executive Function at Age Two Predicts Emergent Mathematics and Literacy at Age Five

Directory of Open Access Journals (Sweden)

Hanna Mulder

2017-10-01

Full Text Available Previous work has shown that individual differences in executive function (EF are predictive of academic skills in preschoolers, kindergartners, and older children. Across studies, EF is a stronger predictor of emergent mathematics than literacy. However, research on EF in children below age three is scarce, and it is currently unknown whether EF, as assessed in toddlerhood, predicts emergent academic skills a few years later. This longitudinal study investigates whether early EF, assessed at two years, predicts (emergent academic skills, at five years. It examines, furthermore, whether early EF is a significantly stronger predictor of emergent mathematics than of emergent literacy, as has been found in previous work on older children. A sample of 552 children was assessed on various EF and EF-precursor tasks at two years. At age five, these children performed several emergent mathematics and literacy tasks. Structural Equation Modeling was used to investigate the relationships between early EF and academic skills, modeled as latent factors. Results showed that early EF at age two was a significant and relatively strong predictor of both emergent mathematics and literacy at age five, after controlling for receptive vocabulary, parental education, and home language. Predictive relations were significantly stronger for mathematics than literacy, but only when a verbal short-term memory measure was left out as an indicator to the latent early EF construct. These findings show that individual differences in emergent academic skills just prior to entry into the formal education system can be traced back to individual differences in early EF in toddlerhood. In addition, these results highlight the importance of task selection when assessing early EF as a predictor of later outcomes, and call for further studies to elucidate the mechanisms through which individual differences in early EF and precursors to EF come about.

Specificity of executive function and theory of mind performance in relation to attention-deficit/hyperactivity symptoms in autism spectrum disorders.

Science.gov (United States)

Lukito, Steve; Jones, Catherine R G; Pickles, Andrew; Baird, Gillian; Happé, Francesca; Charman, Tony; Simonoff, Emily

2017-01-01

Individuals with autism spectrum disorder (ASD) frequently demonstrate symptoms of attention-deficit/hyperactivity disorder (ADHD). Previous findings in children with ASD have suggested that these symptoms are associated with an impairment in executive function (EF) abilities. However, studies rarely considered this association within a single framework that controls for other related factors such as Theory of Mind (ToM) abilities and ASD symptoms. We used structural equation modeling to explore the relations among EF, ToM, and symptoms of ASD and ADHD, using data from a population-based sample of 100 adolescents with ASD and full-scale IQ ≥ 50 (the Special Needs and Autism Project (SNAP) cohort). The study used a multi-measure and multi-informant approach, where performance of inhibition, planning, switching, and working memory tasks indexed EF and performance on tasks involving mentalizing indexed ToM. Measures of ASD and ADHD symptoms included parent and teacher reports and direct observation of the children. Shared source of symptom reporting was accounted for with a parental rating latent factor indexed by symptom measures reported by parents. Impairments in EF abilities were specifically associated with ADHD symptoms while impaired ToM was specifically associated with ASD symptoms, when accounting for the associations of each cognitive domain with the other factors. ASD and ADHD symptom latent factors were also correlated, but this association became nonsignificant once the shared source of reporting from parents was accounted for and within a model that also controlled for the correlated pathway between EF and ToM factors. The specific relations between the cognitive domains and behavioral symptoms remained even after controlling for IQ. In this ASD sample, symptoms of ADHD and ASD are underpinned by separate cognitive domains. The association between EF and ToM impairments is a likely partial explanation for the co-occurrence of ADHD symptoms in ASD

Latent variable models are network models.

Science.gov (United States)

Molenaar, Peter C M

2010-06-01

Cramer et al. present an original and interesting network perspective on comorbidity and contrast this perspective with a more traditional interpretation of comorbidity in terms of latent variable theory. My commentary focuses on the relationship between the two perspectives; that is, it aims to qualify the presumed contrast between interpretations in terms of networks and latent variables.

Heteroscedastic Latent Trait Models for Dichotomous Data.

Science.gov (United States)

Molenaar, Dylan

2015-09-01

Effort has been devoted to account for heteroscedasticity with respect to observed or latent moderator variables in item or test scores. For instance, in the multi-group generalized linear latent trait model, it could be tested whether the observed (polychoric) covariance matrix differs across the levels of an observed moderator variable. In the case that heteroscedasticity arises across the latent trait itself, existing models commonly distinguish between heteroscedastic residuals and a skewed trait distribution. These models have valuable applications in intelligence, personality and psychopathology research. However, existing approaches are only limited to continuous and polytomous data, while dichotomous data are common in intelligence and psychopathology research. Therefore, in present paper, a heteroscedastic latent trait model is presented for dichotomous data. The model is studied in a simulation study, and applied to data pertaining alcohol use and cognitive ability.

A comparison of EF-18 agar and modified brilliant green agar with lutensit for isolation of Salmonella from poultry samples

DEFF Research Database (Denmark)

Petersen, Line Hedegård

1997-01-01

-Vassiliadis broth, and 3) Plating onto EF-18 agar and BGA/L simultaneously. From a total of 1101 samples, Salmonella was isolated from 158, 157 of which were faecal samples. Thirtyone of these isolates were recovered on one medium only, 18 could not be found on BGA/L and 13 could not be found on EF-18 agar....... The relative specificity and sensitivity of each plating agar was determined by enumeration of false-positive and false-negative reactions. EF-18 agar compared favourably with BGA/L, displaying a sensitivity of 0.92 as opposed to 0.89 for BGA/L, calculated for the ''fecal samples'' group only. The calculated...... specificities for each group of samples were likewise considerably higher for EF-18 agar (0.75-0.91) than for BGA/L (0.35-0.55). Though EF-18 agar is slightly more expensive than BGA/L, the routine use of the former may result in a considerable reduction in overall laboratory costs due to its superior...

A Ca2+-calmodulin-eEF2K-eEF2 signalling cascade, but not AMPK, contributes to the suppression of skeletal muscle protein synthesis during contractions

DEFF Research Database (Denmark)

Rose, Adam John; Alsted, Thomas Junker; Jensen, Thomas Elbenhardt

2009-01-01

Skeletal muscle protein synthesis rate decreases during contractions but the underlying regulatory mechanisms are poorly understood. It was hypothesised that there would be a coordinated regulation of eukaryotic elongation factor 2 (eEF2) and eukaryotic initiation factor 4E-binding protein 1 (4EBP1......) phosphorylation by signalling cascades downstream of rises in intracellular [Ca(2+)] and decreased energy charge via AMP activated protein kinase (AMPK) in contracting skeletal muscle. When fast-twitch skeletal muscles were contracted ex vivo using different protocols, the suppression of protein synthesis...... correlated more closely with changes in eEF2 rather than 4EBP1 phosphorylation. Using a combination of Ca(2+) release agents and ATPase inhibitors it was shown that the 60-70% suppression of fast-twitch skeletal muscle protein synthesis during contraction was equally distributed between Ca(2+) and energy...

Use of a Latent Topic Model for Characteristic Extraction from Health Checkup Questionnaire Data.

Science.gov (United States)

Hatakeyama, Y; Miyano, I; Kataoka, H; Nakajima, N; Watabe, T; Yasuda, N; Okuhara, Y

2015-01-01

When patients complete questionnaires during health checkups, many of their responses are subjective, making topic extraction difficult. Therefore, the purpose of this study was to develop a model capable of extracting appropriate topics from subjective data in questionnaires conducted during health checkups. We employed a latent topic model to group the lifestyle habits of the study participants and represented their responses to items on health checkup questionnaires as a probability model. For the probability model, we used latent Dirichlet allocation to extract 30 topics from the questionnaires. According to the model parameters, a total of 4381 study participants were then divided into groups based on these topics. Results from laboratory tests, including blood glucose level, triglycerides, and estimated glomerular filtration rate, were compared between each group, and these results were then compared with those obtained by hierarchical clustering. If a significant (p topic model and hierarchical clustering grouping revealed that, in the latent topic model method, a small group of participants who reported having subjective signs of urinary disorder were allocated to a single group. The latent topic model is useful for extracting characteristics from a small number of groups from questionnaires with a large number of items. These results show that, in addition to chief complaints and history of past illness, questionnaire data obtained during medical checkups can serve as useful judgment criteria for assessing the conditions of patients.

Elucidating the Role of Injury-Induced Electric Fields (EFs) in Regulating the Astrocytic Response to Injury in the Mammalian Central Nervous System.

Science.gov (United States)

Baer, Matthew L; Henderson, Scott C; Colello, Raymond J

2015-01-01

Injury to the vertebrate central nervous system (CNS) induces astrocytes to change their morphology, to increase their rate of proliferation, and to display directional migration to the injury site, all to facilitate repair. These astrocytic responses to injury occur in a clear temporal sequence and, by their intensity and duration, can have both beneficial and detrimental effects on the repair of damaged CNS tissue. Studies on highly regenerative tissues in non-mammalian vertebrates have demonstrated that the intensity of direct-current extracellular electric fields (EFs) at the injury site, which are 50-100 fold greater than in uninjured tissue, represent a potent signal to drive tissue repair. In contrast, a 10-fold EF increase has been measured in many injured mammalian tissues where limited regeneration occurs. As the astrocytic response to CNS injury is crucial to the reparative outcome, we exposed purified rat cortical astrocytes to EF intensities associated with intact and injured mammalian tissues, as well as to those EF intensities measured in regenerating non-mammalian vertebrate tissues, to determine whether EFs may contribute to the astrocytic injury response. Astrocytes exposed to EF intensities associated with uninjured tissue showed little change in their cellular behavior. However, astrocytes exposed to EF intensities associated with injured tissue showed a dramatic increase in migration and proliferation. At EF intensities associated with regenerating non-mammalian vertebrate tissues, these cellular responses were even more robust and included morphological changes consistent with a regenerative phenotype. These findings suggest that endogenous EFs may be a crucial signal for regulating the astrocytic response to injury and that their manipulation may be a novel target for facilitating CNS repair.

Elucidating the Role of Injury-Induced Electric Fields (EFs in Regulating the Astrocytic Response to Injury in the Mammalian Central Nervous System.

Directory of Open Access Journals (Sweden)

Matthew L Baer

Full Text Available Injury to the vertebrate central nervous system (CNS induces astrocytes to change their morphology, to increase their rate of proliferation, and to display directional migration to the injury site, all to facilitate repair. These astrocytic responses to injury occur in a clear temporal sequence and, by their intensity and duration, can have both beneficial and detrimental effects on the repair of damaged CNS tissue. Studies on highly regenerative tissues in non-mammalian vertebrates have demonstrated that the intensity of direct-current extracellular electric fields (EFs at the injury site, which are 50-100 fold greater than in uninjured tissue, represent a potent signal to drive tissue repair. In contrast, a 10-fold EF increase has been measured in many injured mammalian tissues where limited regeneration occurs. As the astrocytic response to CNS injury is crucial to the reparative outcome, we exposed purified rat cortical astrocytes to EF intensities associated with intact and injured mammalian tissues, as well as to those EF intensities measured in regenerating non-mammalian vertebrate tissues, to determine whether EFs may contribute to the astrocytic injury response. Astrocytes exposed to EF intensities associated with uninjured tissue showed little change in their cellular behavior. However, astrocytes exposed to EF intensities associated with injured tissue showed a dramatic increase in migration and proliferation. At EF intensities associated with regenerating non-mammalian vertebrate tissues, these cellular responses were even more robust and included morphological changes consistent with a regenerative phenotype. These findings suggest that endogenous EFs may be a crucial signal for regulating the astrocytic response to injury and that their manipulation may be a novel target for facilitating CNS repair.

The mazEF toxin-antitoxin system as a novel antibacterial target in Acinetobacter baumannii

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Sobhan Ghafourian

2014-07-01

Full Text Available Although analysis of toxin-antitoxin (TA systems can be instructive, to date, there is no information on the prevalence and identity of TA systems based on a large panel of Acinetobacter baumannii clinical isolates. The aim of the current study was to screen for functional TA systems among clinical isolates of A. baumannii and to identify the systems’ locations. For this purpose, we screened 85 A. baumannii isolates collected from different clinical sources for the presence of the mazEF, relBE and higBA TA genes. The results revealed that the genes coding for the mazEF TA system were commonly present in all clinical isolates of A. baumannii. Reverse transcriptase-polymerase chain reaction analysis showed that transcripts were produced in the clinical isolates. Our findings showed that TA genes are prevalent, harboured by chromosomes and transcribed within A. baumannii. Hence, activation of the toxin proteins in the mazEF TA system should be investigated further as an effective antibacterial strategy against this bacterium.

Isoforms of elongation factor eEF1A may be differently regulated at post-transcriptional level in breast cancer progression

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Vislovukh A. A.

2013-01-01

Full Text Available Eukaryotic translation elongation factor 1A exists as two 98 % homologous isoforms: eEF1A1 (A1 and eEF1A2 (A2 which are tissue and development specific. Despite high homology in an open reading frame (ORF region, mRNAs coding for eEF1A1 and eEF1A2 are different in their untranslated regions (UTR, suggesting a possibility of their dissimilar post-transcriptional regulation. Aim. To analyze the existence of cis-acting motifs in the UTRs of EEF1A1/A2 mRNAs, to confirm the possibility of post-transcriptional control of eEF1A1 and eEF1A2 expression. Methods. An ensemble of bioinformatic methods was applied to predict regulatory motifs in the UTRs of EEF1A1/A2 mRNAs. Dual-luciferase reporter assay was employed to detect post-transcriptional regulation of eEF1A1/A2 expression. Results. Numerous regulatory motifs in the UTR of EEF1A1/A2 mRNAs were found bioinformatically. The experimental evidence was obtained for the existence of negative regulation of EEF1A1 and positive regulation of EEF1A2 mRNA in the model of breast cancer development. Conclusions. EEF1A1 and EEF1A2 mRNAs contain distinct motifs in the UTRs and are differently regulated in cancer suggesting the possibility of their control by different cellular signals.

Latent lifestyle preferences and household location decisions

Science.gov (United States)

Walker, Joan L.; Li, Jieping

2007-04-01

Lifestyle, indicating preferences towards a particular way of living, is a key driver of the decision of where to live. We employ latent class choice models to represent this behavior, where the latent classes are the lifestyles and the choice model is the choice of residential location. Thus, we simultaneously estimate lifestyle groups and how lifestyle impacts location decisions. Empirical results indicate three latent lifestyle segments: suburban dwellers, urban dwellers, and transit-riders. The suggested lifestyle segments have intriguing policy implications. Lifecycle characteristics are used to predict lifestyle preferences, although there remain significant aspects that cannot be explained by observable variables.

Fabrication and tests of EF conductors for JT-60SA

Energy Technology Data Exchange (ETDEWEB)

Kizu, Kaname, E-mail: kizu.kaname@jaea.go.jp [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan); Kashiwa, Yoshitoshi; Murakami, Haruyuki [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan); Obana, Tetsuhiro; Takahata, Kazuya [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Tsuchiya, Katsuhiko; Yoshida, Kiyoshi [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan); Hamaguchi, Shinji [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Matsui, Kunihiro [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan); Nakamura, Kazuya; Takao, Tomoaki [Sophia University, Tokyo 102-8554 (Japan); Yanagi, Nagato; Imagawa, Shinsaku; Mito, Toshiyuki [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan)

2011-10-15

The conductors for plasma equilibrium field (EF) coils of JT-60SA are NbTi cable-in-conduit (CIC) conductor with stainless steel 316L jacket. The production of superconductors for actual EF coils started from February 2010. Nine superconductors with 444 m in length were produced up to July 2010. More than 300 welding of jackets were performed. Six nonconformities were found by inspections as go gauge, visual inspection and X-ray test. In order to shorten the manufacturing time schedule, helium leak test was conducted at once after connecting the long length jacket not just after the welding. The maximum force to pull the cable into jacket was about 7.6 kN on average. The mass flow rates of 9 conductors showed almost same values indicating that there are no blockages in the conductors. The measured current sharing temperature agreed with the expectation values from strand performance indicating that no degradation was caused by production process. The coupling time constants of conductors ranged from 80 to 90 ms which are much smaller than the design value of 200 ms.

Tropical Gravity Wave Momentum Fluxes and Latent Heating Distributions

Science.gov (United States)

Geller, Marvin A.; Zhou, Tiehan; Love, Peter T.

2015-01-01

Recent satellite determinations of global distributions of absolute gravity wave (GW) momentum fluxes in the lower stratosphere show maxima over the summer subtropical continents and little evidence of GW momentum fluxes associated with the intertropical convergence zone (ITCZ). This seems to be at odds with parameterizations forGWmomentum fluxes, where the source is a function of latent heating rates, which are largest in the region of the ITCZ in terms of monthly averages. The authors have examined global distributions of atmospheric latent heating, cloud-top-pressure altitudes, and lower-stratosphere absolute GW momentum fluxes and have found that monthly averages of the lower-stratosphere GW momentum fluxes more closely resemble the monthly mean cloud-top altitudes rather than the monthly mean rates of latent heating. These regions of highest cloud-top altitudes occur when rates of latent heating are largest on the time scale of cloud growth. This, plus previously published studies, suggests that convective sources for stratospheric GW momentum fluxes, being a function of the rate of latent heating, will require either a climate model to correctly model this rate of latent heating or some ad hoc adjustments to account for shortcomings in a climate model's land-sea differences in convective latent heating.

Repeatability of tumour hypoxia imaging using [{sup 18}F]EF5 PET/CT in head and neck cancer

Energy Technology Data Exchange (ETDEWEB)

Silvoniemi, Antti [University of Turku, Turku PET Centre (Finland); Turku University Hospital, Department of Otorhinolaryngology - Head and Neck Surgery (Finland); Suilamo, Sami [Turku University Hospital, Department of Oncology and Radiotherapy (Finland); Turku University Hospital, Department of Medical Physics (Finland); Laitinen, Timo; Forsback, Sarita; Solin, Olof [University of Turku, Turku PET Centre (Finland); Loeyttyniemi, Eliisa [University of Turku, Department of Biostatistics, Turku (Finland); Vaittinen, Samuli [Turku University Hospital, Department of Pathology (Finland); Saunavaara, Virva [University of Turku, Turku PET Centre (Finland); Turku University Hospital, Department of Medical Physics (Finland); Groenroos, Tove J.; Minn, Heikki [University of Turku, Turku PET Centre (Finland); Turku University Hospital, Department of Oncology and Radiotherapy (Finland)

2018-02-15

Hypoxia contributes to radiotherapy resistance and more aggressive behaviour of several types of cancer. This study was designed to evaluate the repeatability of intratumour uptake of the hypoxia tracer [{sup 18}F]EF5 in paired PET/CT scans. Ten patients with newly diagnosed head and neck cancer (HNC) received three static PET/CT scans before chemoradiotherapy: two with [{sup 18}F]EF5 a median of 7 days apart and one with [{sup 18}F]FDG. Metabolically active primary tumour volumes were defined in [{sup 18}F]FDG images and transferred to co-registered [{sup 18}F]EF5 images for repeatability analysis. A tumour-to-muscle uptake ratio (TMR) of 1.5 at 3 h from injection of [{sup 18}F]EF5 was used as a threshold representing hypoxic tissue. In 10 paired [{sup 18}F]EF5 PET/CT image sets, SUVmean, SUVmax, and TMR showed a good correlation with the intraclass correlation coefficients of 0.81, 0.85, and 0.87, respectively. The relative coefficients of repeatability for these parameters were 15%, 17%, and 10%, respectively. Fractional hypoxic volumes of the tumours in the repeated scans had a high correlation using the Spearman rank correlation test (r = 0.94). In a voxel-by-voxel TMR analysis between the repeated scans, the mean of Pearson correlation coefficients of individual patients was 0.65. The mean (± SD) difference of TMR in the pooled data set was 0.03 ± 0.20. Pretreatment [{sup 18}F]EF5 PET/CT within one week shows high repeatability and is feasible for the guiding of hypoxia-targeted treatment interventions in HNC. (orig.)

Characterization of the 1st and 2nd EF-hands of NADPH oxidase 5 by fluorescence, isothermal titration calorimetry, and circular dichroism

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Wei Chin-Chuan

2012-04-01

Full Text Available Abstract Background Superoxide generated by non-phagocytic NADPH oxidases (NOXs is of growing importance for physiology and pathobiology. The calcium binding domain (CaBD of NOX5 contains four EF-hands, each binding one calcium ion. To better understand the metal binding properties of the 1st and 2nd EF-hands, we characterized the N-terminal half of CaBD (NCaBD and its calcium-binding knockout mutants. Results The isothermal titration calorimetry measurement for NCaBD reveals that the calcium binding of two EF-hands are loosely associated with each other and can be treated as independent binding events. However, the Ca2+ binding studies on NCaBD(E31Q and NCaBD(E63Q showed their binding constants to be 6.5 × 105 and 5.0 × 102 M-1 with ΔHs of -14 and -4 kJ/mol, respectively, suggesting that intrinsic calcium binding for the 1st non-canonical EF-hand is largely enhanced by the binding of Ca2+ to the 2nd canonical EF-hand. The fluorescence quenching and CD spectra support a conformational change upon Ca2+ binding, which changes Trp residues toward a more non-polar and exposed environment and also increases its α-helix secondary structure content. All measurements exclude Mg2+-binding in NCaBD. Conclusions We demonstrated that the 1st non-canonical EF-hand of NOX5 has very weak Ca2+ binding affinity compared with the 2nd canonical EF-hand. Both EF-hands interact with each other in a cooperative manner to enhance their Ca2+ binding affinity. Our characterization reveals that the two EF-hands in the N-terminal NOX5 are Ca2+ specific. Graphical abstract

The ability of AIF-1 to activate human vascular smooth muscle cells is lost by mutations in the EF-hand calcium-binding region

International Nuclear Information System (INIS)

Autieri, Michael V.; Chen Xing

2005-01-01

Allograft Inflammatory Factor-1 (AIF-1) is a cytoplasmic calcium-binding protein expressed in vascular smooth muscle cells (VSMC) in response to injury or cytokine stimulation. AIF-1 contains a partially conserved EF-hand calcium-binding domain, and participates in VSMC activation by activation of Rac1 and induction of Granulocyte-Colony Stimulating Factor (G-CSF) expression; however, the mechanism whereby AIF-1 mediates these effects is presently uncharacterized. To determine if calcium binding plays a functional role in AIF-1 activity, a single site-specific mutation was made in the EF-hand calcium-binding domain to abrogate binding of calcium (AIF-1ΔA), which was confirmed by calcium overlay. Functionally, similar to wild-type AIF-1, AIF-1ΔA was able to polymerize F-actin in vitro. However, in contrast to wild-type AIF-1, over-expression of AIF-1ΔA was unable to increase migration or proliferation of primary human VSMC. Further, it was unable to activate Rac1, or induce G-CSF expression to the degree as wild-type AIF-1. Taken together, modification of the wild-type EF-hand domain and native calcium-binding activity results in a loss of AIF-1 function. We conclude that appropriate calcium-binding potential is critical in AIF-1-mediated effects on VSMC pathophysiology, and that AIF-1 activity is mediated by Rac1 activation and G-CSF expression

Learning Latent Vector Spaces for Product Search

NARCIS (Netherlands)

Van Gysel, C.; de Rijke, M.; Kanoulas, E.

2016-01-01

We introduce a novel latent vector space model that jointly learns the latent representations of words, e-commerce products and a mapping between the two without the need for explicit annotations. The power of the model lies in its ability to directly model the discriminative relation between

Cytokine profile in patients with early latent syphilis

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Zakharov S.V.

2018-03-01

Full Text Available The purpose of this study was to study the change in the content of the most active cytokines (interleukins 6 and 10 during the formation of the immune response in patients with latent early syphilis, as well as to study the possible relationship between the concentrations of these cytokines and the duration of the disease. In 50 patients with early latent syphilis, the concentration of interleukins 6 and 10 in serum was studied. The serum level of interleukins was studied by the enzyme immunoassay. A statistically significant increase in the concentration of interleukin 6 in the blood of patients with latent syphilis and decrease in the interleukin 10 concentration in comparison with healthy people was established. At the same time, in patients with latent syphilis with term of infection for more than 1 year, interleukin 10 has been expressed, as compared with healthy people and, especially, with patients with syphilis with a duration of infection of up to 1 year. Along with this, a lower degree of increase in the concentration of interleukin 6 in patients with latent syphilis with a duration of infection over 1 year has been established, as compared with patients with latent syphilis with a term of infection up to 1 year, against the background of its increased concentration as compared with a group of healthy individuals.

Membrane Fouling Potential of Secondary Effluent Organic Matter (EfOM) from Conventional Activated Sludge Process

KAUST Repository

Wei, Chunhai; Amy, Gary L.

2012-01-01

Secondary effluent organic matter (EfOM) from a conventional activated sludge process was filtered through constant-pressure dead-end filtration tests with a sequential ultrafiltration (UF, molecular weight cut-off (MWCO) of 10k Dalton) and nanofiltration (NF, MWCO of 200 Dalton) array to investigate its membrane fouling potential. Advanced analytical methods including liquid chromatography with online carbon detection (LC-OCD) and fluorescent excitation-emission matrix (F-EEM) were employed for EfOM characterization. EfOM consisted of humic substances and building blocks, low molecular weight (LMW) neutrals, biopolymers (mainly proteins) and hydrophobic organics according to the sequence of their organic carbon fractions. The UF rejected only biopolymers and the NF rejected most humics and building blocks and a significant part of LMW neutrals. Simultaneous occurrence of cake layer and standard blocking during the filtration process of both UF and NF was identified according to constant-pressure filtration equations, which was possibly caused by the heterogeneous nature of EfOM with a wide MW distribution (several ten to several million Dalton). Thus the corresponding two fouling indices (kc for cake layer and ks for standard blocking) from UF and NF could characterize the fouling potential of macromolecular biopolymers and low to intermediate MW organics (including humics, building blocks, LMW neutrals), respectively. Compared with macromolecular biopolymers, low to intermediate MW organics exhibited a much higher fouling potential due to their lower molecular weight and higher concentration.

Predictive potential of macrophage migration inhibitory factor (MIF) in patients with heart failure with preserved ejection fraction (HFpEF).

Science.gov (United States)

Luedike, Peter; Alatzides, Georgios; Papathanasiou, Maria; Heisler, Martin; Pohl, Julia; Lehmann, Nils; Rassaf, Tienush

2018-05-04

Prognostication in heart failure with preserved ejection fraction (HFpEF) is challenging and novel biomarkers are urgently needed. Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine that plays a crucial role in cardiovascular and various inflammatory diseases. Whether MIF is involved in HFpEF is unknown. Sixty-two patients with HFpEF were enrolled and followed up for 180 days. MIF plasma levels as well as natriuretic peptide (NP) levels were assessed. High MIF levels significantly predicted the combined end-point of all-cause death or hospitalization at 180 days in the univariate analysis (HR 2.41, 95% CI 1.12-5.19, p = 0.025) and after adjustment for relevant covariates in a Cox proportional hazard regression model (HR 2.35, 95% CI 1.05-5.27, p = 0.0374). Furthermore, MIF levels above the median were associated with higher pulmonary artery systolic pressure (PASP) as assessed by echocardiography (PASP 31 mmHg vs 48 mmHg in the low- and high-MIF group, respectively, p = 0.017). NPs significantly correlated with MIF in HFpEF patients (BNP p = 0.011; r = 0.32; NT-proBNP p = 0.027; r = 0.28). MIF was associated with clinical outcomes and might be involved in the pathophysiology of pulmonary hypertension in patients with HFpEF. These first data on MIF in HFpEF should stimulate further research to elucidate the role of this cytokine in heart failure. Trial registration NCT03232671.

[sup 31]P-magnetic resonance spectroscopy: Impaired energy metabolism in latent hyperthyroidism. [sup 31]Phosphor-Kernspinspektroskopie: Gestoerter Energiestoffwechsel bei latenter Hyperthyreose

Energy Technology Data Exchange (ETDEWEB)

Theissen, P. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany)); Kaldewey, S. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany)); Moka, D. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany)); Bunke, J. (Philips Medizin Systeme, Hamburg (Germany)); Voth, E. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany)); Schicha, H. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany))

1993-06-01

[sup 31]Phosphorous magnetic resonance spectroscopy allows an in vivo examination of energy metabolism. The present study was designed to evaluate whether in patients with latent hyperthyroidism alterations of muscle energy metabolism could be found similar to those observed in patients with overt hyperthyroidism. In 10 patients with overt hyperthyroidism before therapy and 20 with latent hyperthyroidism (also without therapy) and in 24 healthy volunteers magnetic resonance spectroscopy of the calf muscle was performed within a 1.5-Tesla magnet. Muscle concentrations of phosphocreatine, inorganic phosphate, and ATP were quantified compared to an external standard solution of K[sub 2]HPO[sub 4]. In the patients with overt hyperthyroidism and with latent hyperthyroidism a significant decrease of phosphocreatine was found. Further, the ATP concentration in patients with latent and manifest hyperthyroidism tended towards lower values. There were no significant differences in the decrease of phosphocreatine and ATP between both patient groups. Therefore, this study for the first time shows that alterations of energy metabolism in latent hyperthyroidism can be measured and that they are similar to those observed in overt hyperthyroidism. (orig.)

Application of UV and X-Ray radiation for refreshing of old latent fingerprints in the cyanoacrylate fuming technique - preliminary study

International Nuclear Information System (INIS)

Radiceska, Pavlina; Ristova, Mimoza

2013-01-01

The work described below focuses on enhancement/refreshment of older latent fingerprints onto a non porous (glass) surface. The aging of the fingerprints is a major problem of the forensic science, because of the compound’s degradation under the influence of a variety of atmospheric parameters, in addition to the time factor. The humidification extent on the latent fingerprints appeared to be one of the critical factors for the deposition of the cyanoacrylate on the finger-marks, since the unsaturated bonds from lipid content from the latent fingerprints serve as active water condensation centers. In the present work we show results from the enhancement of aged latent fingerprint details by activation of the humidity condensation centers with exposition to UV or X-ray radiation prior to their developing into the cyanoacrylate fuming chamber. The aging of the latent fingerprints on glass surfaces with the time for given conditions was established. A term “critical day” was introduced as the day when the detectable details from the latent fingerprints dropped to one half of the initial number of details, recovered from identical fresh latent fingerprint. As the fingerprints were aged to the “critical day”, one third of the samples were exposed to a UV for 15 minutes, another third to 15 minutes of X-ray radiation and the last third was kept unexposed. All the samples were developed into a single cyanoacrylate fuming process. The results showed that in both UV and X-ray cases, a considerable enhancement/refreshment, in approximately 50% of the aged latent fingerprints, has been achieved with only a short term irradiation (15 minutes). (Author)

Classification criteria of syndromes by latent variable models

DEFF Research Database (Denmark)

Petersen, Janne

2010-01-01

patient's characteristics. These methods may erroneously reduce multiplicity either by combining markers of different phenotypes or by mixing HALS with other processes such as aging. Latent class models identify homogenous groups of patients based on sets of variables, for example symptoms. As no gold......The thesis has two parts; one clinical part: studying the dimensions of human immunodeficiency virus associated lipodystrophy syndrome (HALS) by latent class models, and a more statistical part: investigating how to predict scores of latent variables so these can be used in subsequent regression...... standard exists for diagnosing HALS the normally applied diagnostic models cannot be used. Latent class models, which have never before been used to diagnose HALS, make it possible, under certain assumptions, to: statistically evaluate the number of phenotypes, test for mixing of HALS with other processes...

Latent Transition Analysis with a Mixture Item Response Theory Measurement Model

Science.gov (United States)

Cho, Sun-Joo; Cohen, Allan S.; Kim, Seock-Ho; Bottge, Brian

2010-01-01

A latent transition analysis (LTA) model was described with a mixture Rasch model (MRM) as the measurement model. Unlike the LTA, which was developed with a latent class measurement model, the LTA-MRM permits within-class variability on the latent variable, making it more useful for measuring treatment effects within latent classes. A simulation…

A Probability Distribution over Latent Causes, in the Orbitofrontal Cortex.

Science.gov (United States)

Chan, Stephanie C Y; Niv, Yael; Norman, Kenneth A

2016-07-27

The orbitofrontal cortex (OFC) has been implicated in both the representation of "state," in studies of reinforcement learning and decision making, and also in the representation of "schemas," in studies of episodic memory. Both of these cognitive constructs require a similar inference about the underlying situation or "latent cause" that generates our observations at any given time. The statistically optimal solution to this inference problem is to use Bayes' rule to compute a posterior probability distribution over latent causes. To test whether such a posterior probability distribution is represented in the OFC, we tasked human participants with inferring a probability distribution over four possible latent causes, based on their observations. Using fMRI pattern similarity analyses, we found that BOLD activity in the OFC is best explained as representing the (log-transformed) posterior distribution over latent causes. Furthermore, this pattern explained OFC activity better than other task-relevant alternatives, such as the most probable latent cause, the most recent observation, or the uncertainty over latent causes. Our world is governed by hidden (latent) causes that we cannot observe, but which generate the observations we see. A range of high-level cognitive processes require inference of a probability distribution (or "belief distribution") over the possible latent causes that might be generating our current observations. This is true for reinforcement learning and decision making (where the latent cause comprises the true "state" of the task), and for episodic memory (where memories are believed to be organized by the inferred situation or "schema"). Using fMRI, we show that this belief distribution over latent causes is encoded in patterns of brain activity in the orbitofrontal cortex, an area that has been separately implicated in the representations of both states and schemas. Copyright © 2016 the authors 0270-6474/16/367817-12$15.00/0.

Learning Latent Structure in Complex Networks

DEFF Research Database (Denmark)

Mørup, Morten; Hansen, Lars Kai

such as the Modularity, it has recently been shown that latent structure in complex networks is learnable by Bayesian generative link distribution models (Airoldi et al., 2008, Hofman and Wiggins, 2008). In this paper we propose a new generative model that allows representation of latent community structure......Latent structure in complex networks, e.g., in the form of community structure, can help understand network dynamics, identify heterogeneities in network properties, and predict ‘missing’ links. While most community detection algorithms are based on optimizing heuristic clustering objectives...... as in the previous Bayesian approaches and in addition allows learning of node specific link properties similar to that in the modularity objective. We employ a new relaxation method for efficient inference in these generative models that allows us to learn the behavior of very large networks. We compare the link...

Designing sequence to control protein function in an EF-hand protein.

Science.gov (United States)

Bunick, Christopher G; Nelson, Melanie R; Mangahas, Sheryll; Hunter, Michael J; Sheehan, Jonathan H; Mizoue, Laura S; Bunick, Gerard J; Chazin, Walter J

2004-05-19

The extent of conformational change that calcium binding induces in EF-hand proteins is a key biochemical property specifying Ca(2+) sensor versus signal modulator function. To understand how differences in amino acid sequence lead to differences in the response to Ca(2+) binding, comparative analyses of sequence and structures, combined with model building, were used to develop hypotheses about which amino acid residues control Ca(2+)-induced conformational changes. These results were used to generate a first design of calbindomodulin (CBM-1), a calbindin D(9k) re-engineered with 15 mutations to respond to Ca(2+) binding with a conformational change similar to that of calmodulin. The gene for CBM-1 was synthesized, and the protein was expressed and purified. Remarkably, this protein did not exhibit any non-native-like molten globule properties despite the large number of mutations and the nonconservative nature of some of them. Ca(2+)-induced changes in CD intensity and in the binding of the hydrophobic probe, ANS, implied that CBM-1 does undergo Ca(2+) sensorlike conformational changes. The X-ray crystal structure of Ca(2+)-CBM-1 determined at 1.44 A resolution reveals the anticipated increase in hydrophobic surface area relative to the wild-type protein. A nascent calmodulin-like hydrophobic docking surface was also found, though it is occluded by the inter-EF-hand loop. The results from this first calbindomodulin design are discussed in terms of progress toward understanding the relationships between amino acid sequence, protein structure, and protein function for EF-hand CaBPs, as well as the additional mutations for the next CBM design.

The Influence of the Toxin/Antitoxin mazEF on Growth and Survival of Listeria monocytogenes under Stress

DEFF Research Database (Denmark)

Curtis, Thomas; Takeuchi, Ippei; Gram, Lone

2017-01-01

A major factor in the resilience of Listeria monocytogenes is the alternative sigma factor B (σB). Type II Toxin/Antitoxin (TA) systems are also known to have a role in the bacterial stress response upon activation via the ClpP or Lon proteases. Directly upstream of the σB operon in L....... monocytogenes is the TA system mazEF, which can cleave mRNA at UACMU sites. In this study, we showed that the mazEF TA locus does not affect the level of persister formation during treatment with antibiotics in lethal doses, but exerts different effects according to the sub-inhibitory stress added. Growth...... it is not analogous to the system of S. aureus, suggesting a novel mode of action for MazEF in L. monocytogenes....

Cross-cultural adaptation and validity of the "Edmonton Frail Scale - EFS" in a Brazilian elderly sample Adaptación cultural y validez de la Edmonton Frail Scale - EFS en una muestra de ancianos brasileños Adaptação cultural e validade da Edmonton Frail Scale - EFS em uma amostra de idosos brasileiros

Directory of Open Access Journals (Sweden)

Suzele Cristina Coelho Fabrício-Wehbe

2009-12-01

Full Text Available This study aimed to assess the cross-cultural adaptation of the Edmonton Frail Scale (EFS and its validity in a Brazilian elderly sample. Translation and back-translation were performed, as well as discussion with professionals and elderly for conceptual equivalence, semantic validation and pre-test of the scale. The scale was applied to 137 elderly aged 65 years or older who lived in the community. In the know-groups validation of the frailty diagnosis between gender, age and cognitive deficit, elder elderly, female and with a cognitive deficit scored higher on the frailty diagnosis. A negative convergent correlation was found between the EFS and the Functional Independence Measure (FIM (-0.53, pEl objetivo de este estudio fue evaluar la adaptación cultural de la Edmonton Frail Scale (EFS y su validez en una muestra de ancianos brasileños. Fueron realizadas las etapas de traducción y retrotraducción, discusión con profesionales y ancianos para equivalencia conceptual, validación semántica y prueba piloto de la escala. El instrumento fue aplicado en 137 ancianos, con 65 años o más de edad, que vivían en la comunidad. En la validación de grupos conocidos, del diagnóstico de fragilidad entre sexo, edad y déficit cognitivo, los ancianos con edad más avanzada, sexo femenino y con déficit cognitivo tuvieron mayor puntuación en el diagnóstico de fragilidad. Hubo una correlación convergente negativa de la EFS con la Medida de Independencia Funcional (MIF (-0,53, pO objetivo deste estudo foi avaliar a adaptação cultural da Edmonton Frail Scale (EFS e sua validade em uma amostra de idosos brasileiros. Foram realizadas as etapas de tradução e retrotradução, discussão com profissionais e idosos para equivalência conceitual, validação semântica e pré-teste da escala. O instrumento foi aplicado em 137 idosos, com 65 anos ou mais de idade, que viviam na comunidade. Na validação de grupos conhecidos, do diagnóstico de

eEF1A Mediates the Nuclear Export of SNAG-Containing Proteins via the Exportin5-Aminoacyl-tRNA Complex

Directory of Open Access Journals (Sweden)

José Manuel Mingot

2013-11-01

Full Text Available Exportin5 mediates the nuclear export of double-stranded RNAs, including pre-microRNAs, adenoviral RNAs, and tRNAs. When tRNAs are aminoacylated, the Exportin5-aminoacyl (aa-tRNA complex recruits and coexports the translation elongation factor eEF1A. Here, we show that eEF1A binds to Snail transcription factors when bound to their main target, the E-cadherin promoter, facilitating their export to the cytoplasm in association with the aa-tRNA-Exportin5 complex. Snail binds to eEF1A through the SNAG domain, a protein nuclear export signal present in several transcription factor families, and this binding is regulated by phosphorylation. Thus, we describe a nuclear role for eEF1A and provide a mechanism for protein nuclear export that attenuates the activity of SNAG-containing transcription factors.

Morphometry of latent palmprints as a function of time.

Science.gov (United States)

Barros, Rodrigo M; Faria, Bruna E F; Kuckelhaus, Selma A S

2013-12-01

In many crimes, the elapsed time between production and collecting fingermark traces is crucial. and a method able to detect the aging of latent prints would represent an improvement in forensic procedures. Considering that as the latent print gets older, substantial changes in the relative proportion of individual components secreted by skin glands could affect the morphology of ridges, morphometry could be a potential tool to assess the aging of latent fingermarks. Then, considering the very limited research in the field, the present work aims to evaluate the morphometry of latent palmprint ridges, as a function of time, in order to identify an aging pattern. The latent marks were deposited by 20 donors on glass microscope slides considering pressure and contact angle, and then were maintained under controlled environmental conditions. The morphometric study was conducted on marks developed with magnetic powder in 7 different time intervals after deposition (0, 5, 10, 15, 20, 25 or 30 days); 60 ridges were evaluated for each developed mark. The results showed that: 1) the method for the replacement and mixing of skin secretions on the palm was appropriate to ensure reproducibility of latent prints, and 2) considering the studied group, there was a time-dependent reduction in the width of ridges and on the percentage of visible ridges over 30 days. Results suggest the possibility of using the morphometric method to determine an aging profile of latent palmprints on glass surface, aiming for forensic purposes. © 2013.

Incorporating direct marketing activity into latent attrition models

NARCIS (Netherlands)

Schweidel, David A.; Knox, George

2013-01-01

When defection is unobserved, latent attrition models provide useful insights about customer behavior and accurate forecasts of customer value. Yet extant models ignore direct marketing efforts. Response models incorporate the effects of direct marketing, but because they ignore latent attrition,

Bifactor latent structure of attention-deficit/hyperactivity disorder (ADHD)/oppositional defiant disorder (ODD) symptoms and first-order latent structure of sluggish cognitive tempo symptoms.

Science.gov (United States)

Lee, SoYean; Burns, G Leonard; Beauchaine, Theodore P; Becker, Stephen P

2016-08-01

The objective was to determine if the latent structure of attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) symptoms is best explained by a general disruptive behavior factor along with specific inattention (IN), hyperactivity/impulsivity (HI), and ODD factors (a bifactor model) whereas the latent structure of sluggish cognitive tempo (SCT) symptoms is best explained by a first-order factor independent of the bifactor model of ADHD/ODD. Parents' (n = 703) and teachers' (n = 366) ratings of SCT, ADHD-IN, ADHD-HI, and ODD symptoms on the Child and Adolescent Disruptive Behavior Inventory (CADBI) in a community sample of children (ages 5-13; 55% girls) were used to evaluate 4 models of symptom organization. Results indicated that a bifactor model of ADHD/ODD symptoms, in conjunction with a separate first-order SCT factor, was the best model for both parent and teacher ratings. The first-order SCT factor showed discriminant validity with the general disruptive behavior and specific IN factors in the bifactor model. In addition, higher scores on the SCT factor predicted greater academic and social impairment, even after controlling for the general disruptive behavior and 3 specific factors. Consistent with predictions from the trait-impulsivity etiological model of externalizing liability, a single, general disruptive behavior factor accounted for nearly all common variance in ADHD/ODD symptoms, whereas SCT symptoms represented a factor different from the general disruptive behavior and specific IN factor. These results provide additional support for distinguishing between SCT and ADHD-IN. The study also demonstrates how etiological models can be used to predict specific latent structures of symptom organization. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

TRIO-EF a general thermal hydraulics computer code applied to the Avlis process

International Nuclear Information System (INIS)

Magnaud, J.P.; Claveau, M.; Coulon, N.; Yala, P.; Guilbaud, D.; Mejane, A.

1993-01-01

TRIO(EF is a general purpose Fluid Mechanics 3D Finite Element Code. The system capabilities cover areas such as steady state or transient, laminar or turbulent, isothermal or temperature dependent fluid flows; it is applicable to the study of coupled thermo-fluid problems involving heat conduction and possibly radiative heat transfer. It has been used to study the thermal behaviour of the AVLIS process separation module. In this process, a linear electron beam impinges the free surface of a uranium ingot, generating a two dimensional curtain emission of vapour from a water-cooled crucible. The energy transferred to the metal causes its partial melting, forming a pool where strong convective motion increases heat transfer towards the crucible. In the upper part of the Separation Module, the internal structures are devoted to two main functions: vapor containment and reflux, irradiation and physical separation. They are subjected to very high temperature levels and heat transfer occurs mainly by radiation. Moreover, special attention has to be paid to electron backscattering. These two major points have been simulated numerically with TRIO-EF and the paper presents and comments the results of such a computation, for each of them. After a brief overview of the computer code, two examples of the TRIO-EF capabilities are given: a crucible thermal hydraulics model, a thermal analysis of the internal structures

Latent fingerprints on different type of screen protective films

Directory of Open Access Journals (Sweden)

Yuttana Sudjaroen

2016-07-01

Full Text Available The purpose of this research was to study the quality of latent fingerprint on different types of screen protective films including screen protector, matte screen protector, anti-fingerprint clear screen protector and anti-fingerprint matte screen protector by using black powder method in developing latent fingerprints. The fingerprints were performed by 10 volunteers whose fingers (right index, right thumb, left index and left thumb were stubbing at different types of screen protective films and subsequently latent fingerprints were developed by brushing with black powder. Automated Fingerprint Identification System (AFIS counted the numbers of minutiae points from 320 latent fingerprints. Anti-fingerprint matte screen protective film produced the best quality of latent fingerprint with an average minutiae point 72.65, followed by matte screen protective film, clear screen protective film and anti-fingerprint clear screen protective film with an average minutiae point of 155.2, 135.0 and 72.65 respectively. The quality of latent fingerprints developed between a clear and a matte surface of screen protective films showed a significant difference (sig>0.05, whereas the coat and the non-coat with anti-fingerprint chemical revealed a non-significant difference (sig<0.05 in their number of minutiae points.

Impaired left ventricular systolic function reserve limits cardiac output and exercise capacity in HFpEF patients due to systemic hypertension.

Science.gov (United States)

Henein, Michael; Mörner, Stellan; Lindmark, Krister; Lindqvist, Per

2013-09-30

Heart failure (HF) patients with preserved left ventricular (LV) ejection fraction (EF) (HFpEF) due to systemic hypertension (SHT) are known to have limited exercise tolerance. Despite having normal EF at rest, we hypothesize that these patients have abnormal systolic function reserve limiting their exercise capacity. Seventeen patients with SHT (mean age 68 ± 9 years) but no valve disease and 14 healthy individuals (mean age of 65 ± 10 years) underwent resting and peak exercise echocardiography using conventional, tissue Doppler and speckle tracking techniques. The differences between resting and peak exercise values were also analyzed (Δ). Exercise capacity was determined as the workload divided by body surface area. Resting values for left atrial (LA) volume/BSA (r=-0.66, pexercise capacity. LVEF increased during exercise in normals (mean Δ EF=10 ± 8%) but failed to do so in patients (mean Δ EF=0.6 ± 9%, pexercise in patients, to the same extent as it did in normals (0.2 ± 0.2 vs. 0.6 ± 0.3 1/s, pexercise (Δ) in LV lateral wall systolic velocity from tissue Doppler (s') (0.71, pexercise capacity independent of changes in heart rate. HFpEF patients with hypertensive LV disease have significantly limited exercise capacity which is related to left atrial enlargement as well as compromised LV systolic function at the time of the symptoms. The limited myocardial systolic function reserve seems to be underlying important explanation for their limited exercise capacity. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Interexaminer variation of minutia markup on latent fingerprints.

Science.gov (United States)

Ulery, Bradford T; Hicklin, R Austin; Roberts, Maria Antonia; Buscaglia, JoAnn

2016-07-01

Latent print examiners often differ in the number of minutiae they mark during analysis of a latent, and also during comparison of a latent with an exemplar. Differences in minutia counts understate interexaminer variability: examiners' markups may have similar minutia counts but differ greatly in which specific minutiae were marked. We assessed variability in minutia markup among 170 volunteer latent print examiners. Each provided detailed markup documenting their examinations of 22 latent-exemplar pairs of prints randomly assigned from a pool of 320 pairs. An average of 12 examiners marked each latent. The primary factors associated with minutia reproducibility were clarity, which regions of the prints examiners chose to mark, and agreement on value or comparison determinations. In clear areas (where the examiner was "certain of the location, presence, and absence of all minutiae"), median reproducibility was 82%; in unclear areas, median reproducibility was 46%. Differing interpretations regarding which regions should be marked (e.g., when there is ambiguity in the continuity of a print) contributed to variability in minutia markup: especially in unclear areas, marked minutiae were often far from the nearest minutia marked by a majority of examiners. Low reproducibility was also associated with differences in value or comparison determinations. Lack of standardization in minutia markup and unfamiliarity with test procedures presumably contribute to the variability we observed. We have identified factors accounting for interexaminer variability; implementing standards for detailed markup as part of documentation and focusing future training efforts on these factors may help to facilitate transparency and reduce subjectivity in the examination process. Published by Elsevier Ireland Ltd.

Induction of latent memory for conditioned food aversion and its transformation into "active" state depend on translation and transcription processes.

Science.gov (United States)

Solntseva, S V; Nikitin, V P

2014-05-01

Mechanisms of induction and retrieval of latent (hidden) memory for conditioned food aversion were investigated in snails. After initial training (single combination of a food stimulus with electric shock), aversive reactions to presentation of the conditioned food stimulus were not revealed. Repeated presentation of the stimuli in 12 days after the first combination was followed by the appearance of aversive food reactions that persisted for at least 14 days. Injections of inhibitors of protein (cycloheximide) or RNA (α-amanitin) synthesis immediately after the first or second combined presentation of the stimuli disturbed skill performance. We hypothesized that single combination of food and reinforcing stimuli led to translation- and transcription-dependent induction of latent conditioned food aversion memory. Transformation of this memory into an active state after repeated presentation of the stimulus combination also depends on the synthesis of new proteins and RNA.

Latent variables and route choice behavior

DEFF Research Database (Denmark)

Prato, Carlo Giacomo; Bekhor, Shlomo; Pronello, Cristina

2012-01-01

In the last decade, a broad array of disciplines has shown a general interest in enhancing discrete choice models by considering the incorporation of psychological factors affecting decision making. This paper provides insight into the comprehension of the determinants of route choice behavior...... and bound algorithm. A hybrid model consists of measurement equations, which relate latent variables to measurement indicators and utilities to choice indicators, and structural equations, which link travelers’ observable characteristics to latent variables and explanatory variables to utilities. Estimation...

Neurite outgrowth mediated by translation elongation factor eEF1A1: a target for antiplatelet agent cilostazol.

Directory of Open Access Journals (Sweden)

Kenji Hashimoto

Full Text Available Cilostazol, a type-3 phosphodiesterase (PDE3 inhibitor, has become widely used as an antiplatelet drug worldwide. A recent second Cilostazol Stroke Prevention Study demonstrated that cilostazol is superior to aspirin for prevention of stroke after an ischemic stroke. However, its precise mechanisms of action remain to be determined. Here, we report that cilostazol, but not the PDE3 inhibitors cilostamide and milrinone, significantly potentiated nerve growth factor (NGF-induced neurite outgrowth in PC12 cells. Furthermore, specific inhibitors for the endoplasmic reticulum protein inositol 1,4,5-triphosphate (IP(3 receptors and several common signaling pathways (PLC-γ, PI3K, Akt, p38 MAPK, and c-Jun N-terminal kinase (JNK, and the Ras/Raf/ERK/MAPK significantly blocked the potentiation of NGF-induced neurite outgrowth by cilostazol. Using a proteomics analysis, we identified that levels of eukaryotic translation elongation factor eEF1A1 protein were significantly increased by treatment with cilostazol, but not cilostamide, in PC12 cells. Moreover, the potentiating effects of cilostazol on NGF-induced neurite outgrowth were significantly antagonized by treatment with eEF1A1 RNAi, but not the negative control of eEF1A1. These findings suggest that eEF1A1 and several common cellular signaling pathways might play a role in the mechanism of cilostazol-induced neurite outgrowth. Therefore, agents that can increase the eEF1A1 protein may have therapeutic relevance in diverse conditions with altered neurite outgrowth.

A quantitative analysis on latent heat of an aqueous binary mixture.

Science.gov (United States)

Han, Bumsoo; Choi, Jeung Hwan; Dantzig, Jonathan A; Bischof, John C

2006-02-01

The latent heat during phase change of water-NaCl binary mixture was measured using a differential scanning calorimeter, and the magnitude for two distinct phase change events, water/ice and eutectic phase change, were analyzed considering the phase change characteristics of a binary mixture. During the analysis, the latent heat associated with each event was calculated by normalizing the amount of each endothermic peak with only the amount of sample participating in each event estimated from the lever rule for the phase diagram. The resulting latent heat of each phase change measured is 303.7 +/- 2.5 J/g for water/ice phase change, and 233.0 +/- 1.6 J/g for eutectic phase change, respectively regardless of the initial concentration of mixture. Although the latent heats of water/ice phase change in water-NaCl mixtures are closely correlated, further study is warranted to investigate the reason for smaller latent heat of water/ice phase change than that in pure water (335 J/g). The analysis using the lever rule was extended to estimate the latent heat of dihydrate as 115 J/g with the measured eutectic and water/ice latent heat values. This new analysis based on the lever rule will be useful to estimate the latent heat of water-NaCl mixtures at various concentrations, and may become a framework for more general analysis of latent heat of various biological solutions.

Identification of Chinese medicine syndromes in persistent insomnia associated with major depressive disorder: a latent tree analysis.

Science.gov (United States)

Yeung, Wing-Fai; Chung, Ka-Fai; Zhang, Nevin Lian-Wen; Zhang, Shi Ping; Yung, Kam-Ping; Chen, Pei-Xian; Ho, Yan-Yee

2016-01-01

Chinese medicine (CM) syndrome (zheng) differentiation is based on the co-occurrence of CM manifestation profiles, such as signs and symptoms, and pulse and tongue features. Insomnia is a symptom that frequently occurs in major depressive disorder despite adequate antidepressant treatment. This study aims to identify co-occurrence patterns in participants with persistent insomnia and major depressive disorder from clinical feature data using latent tree analysis, and to compare the latent variables with relevant CM syndromes. One hundred and forty-two participants with persistent insomnia and a history of major depressive disorder completed a standardized checklist (the Chinese Medicine Insomnia Symptom Checklist) specially developed for CM syndrome classification of insomnia. The checklist covers symptoms and signs, including tongue and pulse features. The clinical features assessed by the checklist were analyzed using Lantern software. CM practitioners with relevant experience compared the clinical feature variables under each latent variable with reference to relevant CM syndromes, based on a previous review of CM syndromes. The symptom data were analyzed to build the latent tree model and the model with the highest Bayes information criterion score was regarded as the best model. This model contained 18 latent variables, each of which divided participants into two clusters. Six clusters represented more than 50 % of the sample. The clinical feature co-occurrence patterns of these six clusters were interpreted as the CM syndromes Liver qi stagnation transforming into fire, Liver fire flaming upward, Stomach disharmony, Hyperactivity of fire due to yin deficiency, Heart-kidney noninteraction, and Qi deficiency of the heart and gallbladder. The clinical feature variables that contributed significant cumulative information coverage (at least 95 %) were identified. Latent tree model analysis on a sample of depressed participants with insomnia revealed 13 clinical

Prevalence and risk factors of latent Tuberculosis among ...

African Journals Online (AJOL)

Background: Latent Tuberculosis treatment is a key tuberculosis control intervention. Adolescents are a high risk group that is not routinely treated in low income countries. Knowledge of latent Tuberculosis (TB) burden among adolescents may influence policy. Objectives: We determined the prevalence and risk factors of ...

Assessing Trust and Effectiveness in Virtual Teams: Latent Growth Curve and Latent Change Score Models

Directory of Open Access Journals (Sweden)

Michael D. Coovert

2017-08-01

Full Text Available Trust plays a central role in the effectiveness of work groups and teams. This is the case for both face-to-face and virtual teams. Yet little is known about the development of trust in virtual teams. We examined cognitive and affective trust and their relationship to team effectiveness as reflected through satisfaction with one’s team and task performance. Latent growth curve analysis reveals both trust types start at a significant level with individual differences in that initial level. Cognitive trust follows a linear growth pattern while affective trust is overall non-linear, but becomes linear once established. Latent change score models are utilized to examine change in trust and also its relationship with satisfaction with the team and team performance. In examining only change in trust and its relationship to satisfaction there appears to be a straightforward influence of trust on satisfaction and satisfaction on trust. However, when incorporated into a bivariate coupling latent change model the dynamics of the relationship are revealed. A similar pattern holds for trust and task performance; however, in the bivariate coupling change model a more parsimonious representation is preferred.

Thermally activated, single component epoxy systems

KAUST Repository

Unruh, David A.; Pastine, Stefan J.; Moreton, Jessica C.; Frechet, Jean

2011-01-01

A single component epoxy system in which the resin and hardener components found in many two-component epoxies are combined onto the same molecule is described. The single molecule precursor to the epoxy resin contains both multiple epoxide moieties and a diamine held latent by thermally degradable carbamate linkages. These bis-carbamate "single molecule epoxies" have an essentially infinite shelf life and access a significant range in curing temperatures related to the structure of the carbamate linkages used. © 2011 American Chemical Society.

Thermally activated, single component epoxy systems

KAUST Repository

Unruh, David A.

2011-08-23

A single component epoxy system in which the resin and hardener components found in many two-component epoxies are combined onto the same molecule is described. The single molecule precursor to the epoxy resin contains both multiple epoxide moieties and a diamine held latent by thermally degradable carbamate linkages. These bis-carbamate "single molecule epoxies" have an essentially infinite shelf life and access a significant range in curing temperatures related to the structure of the carbamate linkages used. © 2011 American Chemical Society.

The Blind Men and the Elephant: Identification of a Latent Maltreatment Construct for Youth in Foster Care

Science.gov (United States)

Gabrielli, Joy; Jackson, Yo; Tunno, Angela M.; Hambrick, Erin P.

2017-01-01

Child maltreatment is a major public health concern due to its impact on developmental trajectories and consequences across mental and physical health outcomes. Operationalization of child maltreatment has been complicated, as research has used simple dichotomous counts to identification of latent class profiles. This study examines a latent measurement model assessed within foster youth inclusive of indicators of maltreatment chronicity and severity across four maltreatment types: physical, sexual, and psychological abuse, and neglect. Participants were 500 foster youth with a mean age of 12.99 years (SD = 2.95 years). Youth completed survey questions through a confidential audio computer-assisted self-interview program. A two-factor model with latent constructs of chronicity and severity of maltreatment revealed excellent fit across fit indices; however, the latent constructs were correlated .972. A one-factor model also demonstrated excellent model fit to the data (χ2 (16, n = 500) =28.087, p =.031, RMSEA (0.012 – 0.062) =.039, TLI =.990, CFI =.994, SRMR =.025) with a nonsignificant chi-square difference test comparing the one- and two-factor models. Invariance tests across age, gender, and placement type also were conducted with recommendations provided. Results suggest a single-factor latent model of maltreatment severity and chronicity can be attained. Thus, the maltreatment experiences reported by foster youth, though varied and complex, were captured in a model that may prove useful in later predictions of outcome behaviors. Appropriate identification of both the chronicity and severity of maltreatment inclusive of the range of maltreatment types remains a high priority for future research. PMID:28254690

Latent semantic analysis.

Science.gov (United States)

Evangelopoulos, Nicholas E

2013-11-01

This article reviews latent semantic analysis (LSA), a theory of meaning as well as a method for extracting that meaning from passages of text, based on statistical computations over a collection of documents. LSA as a theory of meaning defines a latent semantic space where documents and individual words are represented as vectors. LSA as a computational technique uses linear algebra to extract dimensions that represent that space. This representation enables the computation of similarity among terms and documents, categorization of terms and documents, and summarization of large collections of documents using automated procedures that mimic the way humans perform similar cognitive tasks. We present some technical details, various illustrative examples, and discuss a number of applications from linguistics, psychology, cognitive science, education, information science, and analysis of textual data in general. WIREs Cogn Sci 2013, 4:683-692. doi: 10.1002/wcs.1254 CONFLICT OF INTEREST: The author has declared no conflicts of interest for this article. For further resources related to this article, please visit the WIREs website. © 2013 John Wiley & Sons, Ltd.

Characterization of novel peptide-specific antibodies against the translation elongation factor eEF1A2 and their application for cancer research

Directory of Open Access Journals (Sweden)

Shalak V. F.

2014-11-01

Full Text Available Aim. We intend to characterize the new peptide-specific antibodies against the isoform 2 of translation elongation factor 1A (eEF1A2 and determine its presence in the postoperative samples of human breast, lung and stomach tumor tissues. Methods. The analysis of antibody specificity was performed by enzyme-linked immunosorbent assay, immunoblotting and immunohistochemistry. Immunoblotting and immunohistochemistry were used for the determination of the eEF1A2 in the human tumor samples, as well as in the samples of normal tissues surrounding tumors. Results. The antibodies obtained against the eEF1A2 specifically recognized this protein in the cell extracts and histological sections and did not cross-react with the elongation factor 1A isoform 1. eEF1A2 was revealed in the postoperative samples of breast, lung and stomach tumors as well as in the putative normal tissues surrounding tumors. Conclusions. The antibodies obtained against eEF1A2 are highly specific for the antigen and can be used for the immunological studies of tumors.

Association between latent toxoplasmosis and cognition in adults: a cross-sectional study.

Science.gov (United States)

Gale, S D; Brown, B L; Erickson, L D; Berrett, A; Hedges, D W

2015-04-01

Latent infection from Toxoplasma gondii (T. gondii) is widespread worldwide and has been associated with cognitive deficits in some but not all animal models and in humans. We tested the hypothesis that latent toxoplasmosis is associated with decreased cognitive function in a large cross-sectional dataset, the National Health and Nutrition Examination Survey (NHANES). There were 4178 participants aged 20-59 years, of whom 19.1% had IgG antibodies against T. gondii. Two ordinary least squares (OLS) regression models adjusted for the NHANES complex sampling design and weighted to represent the US population were estimated for simple reaction time, processing speed and short-term memory or attention. The first model included only main effects of latent toxoplasmosis and demographic control variables, and the second added interaction terms between latent toxoplasmosis and the poverty-to-income ratio (PIR), educational attainment and race-ethnicity. We also used multivariate models to assess all three cognitive outcomes in the same model. Although the models evaluating main effects only demonstrated no association between latent toxoplasmosis and the cognitive outcomes, significant interactions between latent toxoplasmosis and the PIR, between latent toxoplasmosis and educational attainment, and between latent toxoplasmosis and race-ethnicity indicated that latent toxoplasmosis may adversely affect cognitive function in certain groups.

A Non-Gaussian Spatial Generalized Linear Latent Variable Model

KAUST Repository

Irincheeva, Irina; Cantoni, Eva; Genton, Marc G.

2012-01-01

We consider a spatial generalized linear latent variable model with and without normality distributional assumption on the latent variables. When the latent variables are assumed to be multivariate normal, we apply a Laplace approximation. To relax the assumption of marginal normality in favor of a mixture of normals, we construct a multivariate density with Gaussian spatial dependence and given multivariate margins. We use the pairwise likelihood to estimate the corresponding spatial generalized linear latent variable model. The properties of the resulting estimators are explored by simulations. In the analysis of an air pollution data set the proposed methodology uncovers weather conditions to be a more important source of variability than air pollution in explaining all the causes of non-accidental mortality excluding accidents. © 2012 International Biometric Society.

A Non-Gaussian Spatial Generalized Linear Latent Variable Model

KAUST Repository

Irincheeva, Irina

2012-08-03

We consider a spatial generalized linear latent variable model with and without normality distributional assumption on the latent variables. When the latent variables are assumed to be multivariate normal, we apply a Laplace approximation. To relax the assumption of marginal normality in favor of a mixture of normals, we construct a multivariate density with Gaussian spatial dependence and given multivariate margins. We use the pairwise likelihood to estimate the corresponding spatial generalized linear latent variable model. The properties of the resulting estimators are explored by simulations. In the analysis of an air pollution data set the proposed methodology uncovers weather conditions to be a more important source of variability than air pollution in explaining all the causes of non-accidental mortality excluding accidents. © 2012 International Biometric Society.

Development of the finite element method in the thermal field. TRIO-EF software for thermal and radiation analysis

International Nuclear Information System (INIS)

Casalotti, N.; Magnaud, J.P.

1989-01-01

The possibilities of the TRIO-EF software in the thermal field are presented. The TRIO-EF is a computer program based on the finite element method and used for three-dimensional incompressible flow analysis. It enables the calculation of three-dimensional heat transfer and the fluid/structure analysis. The geometrically complex radiative reactor systems are taken into account in the form factor calculation. The implemented algorithms are described [fr

Interaction between the cellular protein eEF1A and the 3'-terminal stem-loop of West Nile virus genomic RNA facilitates viral minus-strand RNA synthesis.

Science.gov (United States)

Davis, William G; Blackwell, Jerry L; Shi, Pei-Yong; Brinton, Margo A

2007-09-01

RNase footprinting and nitrocellulose filter binding assays were previously used to map one major and two minor binding sites for the cell protein eEF1A on the 3'(+) stem-loop (SL) RNA of West Nile virus (WNV) (3). Base substitutions in the major eEF1A binding site or adjacent areas of the 3'(+) SL were engineered into a WNV infectious clone. Mutations that decreased, as well as ones that increased, eEF1A binding in in vitro assays had a negative effect on viral growth. None of these mutations affected the efficiency of translation of the viral polyprotein from the genomic RNA, but all of the mutations that decreased in vitro eEF1A binding to the 3' SL RNA also decreased viral minus-strand RNA synthesis in transfected cells. Also, a mutation that increased the efficiency of eEF1A binding to the 3' SL RNA increased minus-strand RNA synthesis in transfected cells, which resulted in decreased synthesis of genomic RNA. These results strongly suggest that the interaction between eEF1A and the WNV 3' SL facilitates viral minus-strand synthesis. eEF1A colocalized with viral replication complexes (RC) in infected cells and antibody to eEF1A coimmunoprecipitated viral RC proteins, suggesting that eEF1A facilitates an interaction between the 3' end of the genome and the RC. eEF1A bound with similar efficiencies to the 3'-terminal SL RNAs of four divergent flaviviruses, including a tick-borne flavivirus, and colocalized with dengue virus RC in infected cells. These results suggest that eEF1A plays a similar role in RNA replication for all flaviviruses.

Latent-failure risk estimates for computer control

Science.gov (United States)

Dunn, William R.; Folsom, Rolfe A.; Green, Owen R.

1991-01-01

It is shown that critical computer controls employing unmonitored safety circuits are unsafe. Analysis supporting this result leads to two additional, important conclusions: (1) annual maintenance checks of safety circuit function do not, as widely believed, eliminate latent failure risk; (2) safety risk remains even if multiple, series-connected protection circuits are employed. Finally, it is shown analytically that latent failure risk is eliminated when continuous monitoring is employed.

Exposing Latent Information in Folksonomies for Reasoning

Science.gov (United States)

2010-01-14

1.73 $.") http://www.w3.org/2006/07/SWD/ SKOS /reference/20081001/ Spiteri, L.F. (2007) "The structure and form of folksonomy tags: The road to the...Exposing Latent Information in Folksonomies for Reasoning January 14, 2010 Sponsored by Defense Advanced Research Projects Agency (DOD...DATES COVERED (From - To! 4/14/2009-12/23/2009 4. TITLE AND SUBTITLE Exposing Latent Information in Folksonomies for Reasoning Sa. CONTRACT

Polytomous latent scales for the investigation of the ordering of items

NARCIS (Netherlands)

Ligtvoet, R.; van der Ark, L.A.; Bergsma, W. P.; Sijtsma, K.

2011-01-01

We propose three latent scales within the framework of nonparametric item response theory for polytomously scored items. Latent scales are models that imply an invariant item ordering, meaning that the order of the items is the same for each measurement value on the latent scale. This ordering

After the storm: personal experiences following an EF4 tornado.

Science.gov (United States)

May, Olivia W; Bigham, Amy B

2012-08-01

In April of 2011, an EF4 tornado ripped through the city of Tuscaloosa, AL, leaving in its wake thousands of destroyed homes and businesses. In the hours and days that followed, the health care community of this city, as well as the entire state of Alabama and the southeastern United States, came together to provide care to hundreds of victims, recovery workers, and volunteers. Copyright © 2012 Elsevier Inc. All rights reserved.

[The EFS metrology: From the production to the reason].

Science.gov (United States)

Reifenberg, J-M; Riout, E; Leroy, A; Begue, S

2014-06-01

In order to answer statutory requirements and to anticipate the future needs and standards, the EFS is committed, since a few years, in a process of harmonization of its metrology function. In particular, the institution has opted for the skills development by internalizing the metrological traceability of the main critical quantities (temperature, volumetric) measurements. The development of metrology so resulted in a significant increase in calibration and testing activities. Methods are homogenized and improved through accreditations. The investment strategies are based on more and more demanding specifications. The performance of the equipments is better known and mastered. Technical expertise and maturity of the national metrology function today are assets to review in more informed ways the appropriateness of the applied periodicities. Analysis of numerous information and data in the calibration and testing reports could be pooled and operated on behalf of the unique establishment. The objective of this article is to illustrate these reflections with a few examples from of a feedback of the EFS Pyrénées Méditerranée. The analysis of some methods of qualification, the exploitation of the historical metrology in order to quantify the risk of non-compliance, and to adapt the control strategy, analysis of the criticality of an instrument in a measurement process, risk analyses are tools that deserve to be more widely exploited for that discipline wins in efficiency at the national level. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Bayesian latent feature modeling for modeling bipartite networks with overlapping groups

DEFF Research Database (Denmark)

Jørgensen, Philip H.; Mørup, Morten; Schmidt, Mikkel Nørgaard

2016-01-01

Bi-partite networks are commonly modelled using latent class or latent feature models. Whereas the existing latent class models admit marginalization of parameters specifying the strength of interaction between groups, existing latent feature models do not admit analytical marginalization...... by the notion of community structure such that the edge density within groups is higher than between groups. Our model further assumes that entities can have different propensities of generating links in one of the modes. The proposed framework is contrasted on both synthetic and real bi-partite networks...... feature representations in bipartite networks provides a new framework for accounting for structure in bi-partite networks using binary latent feature representations providing interpretable representations that well characterize structure as quantified by link prediction....

Latent Growth and Dynamic Structural Equation Models.

Science.gov (United States)

Grimm, Kevin J; Ram, Nilam

2018-05-07

Latent growth models make up a class of methods to study within-person change-how it progresses, how it differs across individuals, what are its determinants, and what are its consequences. Latent growth methods have been applied in many domains to examine average and differential responses to interventions and treatments. In this review, we introduce the growth modeling approach to studying change by presenting different models of change and interpretations of their model parameters. We then apply these methods to examining sex differences in the development of binge drinking behavior through adolescence and into adulthood. Advances in growth modeling methods are then discussed and include inherently nonlinear growth models, derivative specification of growth models, and latent change score models to study stochastic change processes. We conclude with relevant design issues of longitudinal studies and considerations for the analysis of longitudinal data.

Handbook of latent variable and related models

CERN Document Server

Lee, Sik-Yum

2011-01-01

This Handbook covers latent variable models, which are a flexible class of models for modeling multivariate data to explore relationships among observed and latent variables.- Covers a wide class of important models- Models and statistical methods described provide tools for analyzing a wide spectrum of complicated data- Includes illustrative examples with real data sets from business, education, medicine, public health and sociology.- Demonstrates the use of a wide variety of statistical, computational, and mathematical techniques.

Aspects of physicochemical methods for the detection of latent fingerprints

International Nuclear Information System (INIS)

Knowles, A.M.

1978-01-01

This paper reviews physicochemical methods of detecting latent finger-prints on a wide range of materials commonly found at the scene of a crime, with particular emphasis placed on the newer autoradiographic techniques. This is set against a description of studies on the fundamental nature of the latent fingerprint and its host substrate, with a brief review of the history of reagents used in latent fingerprint examination. (author)

Latent M. tuberculosis infection--pathogenesis, diagnosis, treatment and prevention strategies.

Science.gov (United States)

Druszczyńska, Magdalena; Kowalewicz-Kulbat, Magdalena; Fol, Marek; Włodarczyk, Marcin; Rudnicka, Wiesława

2012-01-01

One third of the earths population is infected with Mycobacterium tuberculosis (Mtb), but only 5-10% of the infected individuals develop active tuberculosis (TB) over their lifetime. The remaining 90-95% stay healthy and are called latently infected individuals. They are the biggest reservoir of the tubercle bacilli and identifying the cases of latent TB is a part of the global plan of TB control. From the clinical point of view detection of latent TB infections (LTBI) in individuals with the highest active TB risk including cases of HIV infection, autoimmune inflammatory diseases or cancer, is a priority. This review summarizes the recent findings in the pathogenesis of latent TB, its diagnosis, treatment and prevention.

Identifying subgroups of patients using latent class analysis

DEFF Research Database (Denmark)

Nielsen, Anne Mølgaard; Kent, Peter; Hestbæk, Lise

2017-01-01

BACKGROUND: Heterogeneity in patients with low back pain (LBP) is well recognised and different approaches to subgrouping have been proposed. Latent Class Analysis (LCA) is a statistical technique that is increasingly being used to identify subgroups based on patient characteristics. However......, as LBP is a complex multi-domain condition, the optimal approach when using LCA is unknown. Therefore, this paper describes the exploration of two approaches to LCA that may help improve the identification of clinically relevant and interpretable LBP subgroups. METHODS: From 928 LBP patients consulting...... of statistical performance measures, qualitative evaluation of clinical interpretability (face validity) and a subgroup membership comparison. RESULTS: For the single-stage LCA, a model solution with seven patient subgroups was preferred, and for the two-stage LCA, a nine patient subgroup model. Both approaches...

The fsr Quorum-Sensing System and Cognate Gelatinase Orchestrate the Expression and Processing of Proprotein EF_1097 into the Mature Antimicrobial Peptide Enterocin O16.

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Dundar, Halil; Brede, Dag A; La Rosa, Sabina Leanti; El-Gendy, Ahmed Osama; Diep, Dzung B; Nes, Ingolf F

2015-07-01

A novel antimicrobial peptide designated enterocin O16 was purified from Enterococcus faecalis. Mass spectrometry showed a monoisotopic mass of 7,231 Da, and N-terminal Edman degradation identified a 29-amino-acid sequence corresponding to residues 90 to 119 of the EF_1097 protein. Bioinformatic analysis showed that enterocin O16 is composed of the 68 most C-terminal residues of the EF_1097 protein. Introduction of an in-frame isogenic deletion in the ef1097 gene abolished the production of enterocin O16. Enterocin O16 has a narrow inhibitory spectrum, as it inhibits mostly lactobacilli. Apparently, E. faecalis is intrinsically resistant to the antimicrobial peptide, as no immunity connected to the production of enterocin O16 could be identified. ef1097 has previously been identified as one of three loci regulated by the fsr quorum-sensing system. The introduction of a nonsense mutation into fsrB consistently impaired enterocin O16 production, but externally added gelatinase biosynthesis-activating pheromone restored the antimicrobial activity. Functional genetic analysis showed that the EF_1097 proprotein is processed extracellularly into enterocin O16 by the metalloprotease GelE. Thus, it is evident that the fsr quorum-sensing system constitutes the regulatory unit that controls the expression of the EF_1097 precursor protein and the protease GelE and that the latter is required for the formation of enterocin O16. On the basis of these results, this study identified antibacterial antagonism as a novel aspect related to the function of fsr and provides a rationale for why ef1097 is part of the fsr regulon. The fsr quorum-sensing system modulates important physiological functions in E. faecalis via the activity of GelE. The present study presents a new facet of fsr signaling. The system controls the expression of three primary target operons (fsrABCD, gelE-sprE, and ef1097-ef1097b). We demonstrate that the concerted expression of these operons constitutes the

Using latent class analysis to estimate the test characteristics of the γ-interferon test, the single intradermal comparative tuberculin test and a multiplex immunoassay under Irish conditions

DEFF Research Database (Denmark)

Clegg, Tracy A.; Duignan, Anthony; Whelan, Clare

2011-01-01

Considerable effort has been devoted to improving the existing diagnostic tests for bovine tuberculosis (single intradermal comparative tuberculin test [SICTT] and ¿-interferon assay [¿-IFN]) and to develop new tests. Previously, the diagnostic characteristics (sensitivity, specificity) have been...... estimated in populations with defined infection status. However, these approaches can be problematic as there may be few herds in Ireland where freedom from infection is guaranteed. We used latent class models to estimate the diagnostic characteristics of existing (SICTT and ¿-IFN) and new (multiplex...... immunoassay [Enferplex-TB]) diagnostic tests under Irish field conditions where true disease status was unknown. The study population consisted of herds recruited in areas with no known TB problems (2197 animals) and herds experiencing a confirmed TB breakdown (2740 animals). A Bayesian model was developed...

Towards an HIV-1 cure: measuring the latent reservoir

Science.gov (United States)

Bruner, Katherine M.; Hosmane, Nina N.; Siliciano, Robert F.

2015-01-01

The latent reservoir of HIV-1 in resting memory CD4+ T cells serves as a major barrier to curing HIV-1 infection. While many PCR- and culture-based assays have been used to measure the size of the latent reservoir, correlation between results of different assays is poor and recent studies indicate that no available assay provides an accurate measurement of reservoir size. The discrepancies between assays are a hurdle to clinical trials that aim to measure the efficacy of HIV-1 eradication strategies. Here we describe the advantages and disadvantages of various approaches to measure the latent reservoir. PMID:25747663

Single breath-hold real-time cine MR imaging: improved temporal resolution using generalized autocalibrating partially parallel acquisition (GRAPPA) algorithm

International Nuclear Information System (INIS)

Wintersperger, Bernd J.; Nikolaou, Konstantin; Dietrich, Olaf; Reiser, Maximilian F.; Schoenberg, Stefan O.; Rieber, Johannes; Nittka, Matthias

2003-01-01

The purpose of this study was to test parallel imaging techniques for improvement of temporal resolution in multislice single breath-hold real-time cine steady-state free precession (SSFP) in comparison with standard segmented single-slice SSFP techniques. Eighteen subjects were examined on a 1.5-T scanner using a multislice real-time cine SSFP technique using the GRAPPA algorithm. Global left ventricular parameters (EDV, ESV, SV, EF) were evaluated and results compared with a standard segmented single-slice SSFP technique. Results for EDV (r=0.93), ESV (r=0.99), SV (r=0.83), and EF (r=0.99) of real-time multislice SSFP imaging showed a high correlation with results of segmented SSFP acquisitions. Systematic differences between both techniques were statistically non-significant. Single breath-hold multislice techniques using GRAPPA allow for improvement of temporal resolution and for accurate assessment of global left ventricular functional parameters. (orig.)

Ridge Width Correlations between Inked Prints and Powdered Latent Fingerprints.

Science.gov (United States)

De Alcaraz-Fossoul, Josep; Barrot-Feixat, Carme; Zapico, Sara C; Mancenido, Michelle; Broatch, Jennifer; Roberts, Katherine A; Carreras-Marin, Clara; Tasker, Jack

2017-10-03

A methodology to estimate the time of latent fingerprint deposition would be of great value to law enforcement and courts. It has been observed that ridge topography changes as latent prints age, including the widths of ridges that could be measured as a function of time. Crime suspects are commonly identified using fingerprint databases that contain reference inked tenprints (flat and rolled impressions). These can be of interest in aging studies as they provide baseline information relating to the original (nonaged) ridges' widths. In practice, the age of latent fingerprints could be estimated following a comparison process between the evidentiary aged print and the corresponding reference inked print. The present article explores possible correlations between inked and fresh latent fingerprints deposited on different substrates and visualized with TiO 2 . The results indicate that the ridge width of flat inked prints is most similar to fresh latent fingerprints , and these should be used as the comparison standard for future aging studies. © 2017 American Academy of Forensic Sciences.

Study of noninvasive detection of latent fingerprints using UV laser

Science.gov (United States)

Li, Hong-xia; Cao, Jing; Niu, Jie-qing; Huang, Yun-gang; Mao, Lin-jie; Chen, Jing-rong

2011-06-01

Latent fingerprints present a considerable challenge in forensics, and noninvasive procedure that captures a digital image of the latent fingerprints is significant in the field of criminal investigation. The capability of photography technologies using 266nm UV Nd:YAG solid state laser as excitation light source to provide detailed images of unprocessed latent fingerprints is demonstrated. Unprocessed latent fingerprints were developed on various non-absorbent and absorbing substrates. According to the special absorption, reflection, scattering and fluorescence characterization of the various residues in fingerprints (fatty acid ester, protein, and carbosylic acid salts etc) to the UV light to weaken or eliminate the background disturbance and increase the brightness contrast of fingerprints with the background, and using 266nm UV laser as excitation light source, fresh and old latent fingerprints on the surface of four types of non-absorbent objects as magazine cover, glass, back of cellphone, wood desktop paintwork and two types of absorbing objects as manila envelope, notebook paper were noninvasive detected and appeared through reflection photography and fluorescence photography technologies, and the results meet the fingerprint identification requirements in forensic science.

Inhibition of IkappaB kinase-nuclear factor-kappaB signaling pathway by 3,5-bis(2-flurobenzylidene)piperidin-4-one (EF24), a novel monoketone analog of curcumin.

Science.gov (United States)

Kasinski, Andrea L; Du, Yuhong; Thomas, Shala L; Zhao, Jing; Sun, Shi-Yong; Khuri, Fadlo R; Wang, Cun-Yu; Shoji, Mamoru; Sun, Aiming; Snyder, James P; Liotta, Dennis; Fu, Haian

2008-09-01

The nuclear factor-kappaB (NF-kappaB) signaling pathway has been targeted for therapeutic applications in a variety of human diseases, includuing cancer. Many naturally occurring substances, including curcumin, have been investigated for their actions on the NF-kappaB pathway because of their significant therapeutic potential and safety profile. A synthetic monoketone compound termed 3,5-bis(2-flurobenzylidene)piperidin-4-one (EF24) was developed from curcumin and exhibited potent anticancer activity. Here, we report a mechanism by which EF24 potently suppresses the NF-kappaB signaling pathway through direct action on IkappaB kinase (IKK). We demonstrate that 1) EF24 induces death of lung, breast, ovarian, and cervical cancer cells, with a potency about 10 times higher than that of curcumin; 2) EF24 rapidly blocks the nuclear translocation of NF-kappaB, with an IC(50) value of 1.3 microM compared with curcumin, with an IC(50) value of 13 microM; 3) EF24 effectively inhibits tumor necrosis factor (TNF)-alpha-induced IkappaB phosphorylation and degradation, suggesting a role of this compound in targeting IKK; and 4) EF24 indeed directly inhibits the catalytic activity of IKK in an in vitro-reconstituted system. Our study identifies IKK as an effective target for EF24 and provides a molecular explanation for a superior activity of EF24 over curcumin. The effective inhibition of TNF-alpha-induced NF-kappaB signaling by EF24 extends the therapeutic application of EF24 to other NF-kappaB-dependent diseases, including inflammatory diseases such as rheumatoid arthritis.

Ativação da proteína TGFbetaI latente em pulmão irradiado in vivo Latent TGFbeta1 activation in the lung irradiated in vivo

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MARCOS DUARTE MATTOS

2002-12-01

Full Text Available OBJETIVO: Investigar no pulmão, por imunohistoquímica, a localização das proteínas TGFbeta1 latente e TGFbeta1 ativa, se ocorre ativação radioinduzida da proteína TGFbeta1 latente e a distribuição das fibras colágenas em diversos períodos de tempo após irradiação. MÉTODOS: 32 camundongos isogênicos (C57BL foram divididos em dois grupos: GI (não irradiado com 12 animais e GII (irradiado com 20 animais. Os animais do GII receberam radiação gama (telecobaltoterapia, 60Co, com rendimento de 0,97Gy/min, dose única de 7Gy em corpo inteiro. Os camundongos dos grupos I e II foram sacrificados por estiramento cervical nos períodos de 1, 14, 30 e 90 dias após irradiação. RESULTADOS: Os pulmões irradiados apresentaram: 1 congestão vascular e espessamento dos septos alveolares aos 30 dias e mais intensamente aos 90 dias depois da irradiação; 2 aumento significante da deposição de colágeno em todos os períodos de tempo após irradiação; 3 fraca ativação da proteína TGFbeta1 latente em um dia e intensa aos 14 dias depois da irradiação em brônquios e alvéolos. Nossos resultados sugerem que células dos brônquios e alvéolos podem participar do complexo mecanismo de fibrose pulmonar radioinduzida atuando como fontes da proteína TGFbeta1 ativa.PURPOSE: assess the latent and active TGFb1 localization in the lung, whether or not radiation induces latent TGFbeta1 activation, and the distribution of collagen fibers in the irradiated lung. METHODS: Thirty two C57BL mice were randomly assigned in two groups: GI (non irradiated animals and GII (irradiated animals. The mice from GII received a single whole ¾ body radiation dose of 7Gy, using a 60Co source at a dose rate of 0.97 Gy/min. They were sacrificed by cervical dislocation at 1, 14, 30 and 90 days after radiation. RESULTS: The irradiated lungs showed: 1 vascular congestion and thickness of the alveolar septa 30 days and more intense 90 days after irradiation; 2

Latent tuberculosis in nursing professionals of a Brazilian hospital

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Valim Andréia

2011-05-01

Full Text Available Abstract Tuberculosis (TB is considered an occupational disease among health-care workers (HCWs. Direct contact with TB patients leads to an increased risk to become latently infected by Mycobacterium tuberculosis. The objective of this study is to estimate the prevalence of latent M. tuberculosis minfection among nursing professionals of a hospital in Rio Grande do Sul, Brazil, assessed by tuberculin skin test (TST. From November 2009 to May 2010, latent M. tuberculosis infection was assessed by TST in 55 nursing professionals. Epidemiological information was collected using a standardized questionnaire. A positive TST result (> or = 10 mm was observed in 47.3% of the HCWs tested. There was no significant difference in TST positivity when duration of employment or professional category (technician or nurse was evaluated. The results of this work reinforce the need for control measures to prevent latent M. tuberculosis infection among nursing professionals at the hospital where the study was conducted.

Primiparous women's preferences for care during a prolonged latent phase of labour.

Science.gov (United States)

Ängeby, Karin; Wilde-Larsson, Bodil; Hildingsson, Ingegerd; Sandin-Bojö, Ann-Kristin

2015-10-01

To investigate primiparous women's preferences for care during a prolonged latent phase of labour. A qualitative study based on focus groups and individual interviews and analysed with inductive content analysis. Sixteen primiparous women with a prolonged latent phase of labour >18 hours were interviewed in five focus groups (n = 11) or individually (n = 5). One main category emerged "Beyond normality - a need of individual adapted guidance in order to understand and manage an extended latent phase of labour" which covers the women's preferences during the prolonged latent phase. Five categories were generated from the data: "A welcoming manner and not being rejected", "Individually adapted care", "Important information which prepares for reality and coping", "Participation and need for feedback" and "Staying nearby the labour ward or being admitted for midwifery support". Women with a prolonged latent phase of labour sought to use their own resources, but their needs for professional support increased as time passed. A welcoming attitude from an available midwife during the latent phase created a feeling of security, and personally adapted care was perceived positively. Women with a prolonged latent phase of labour preferred woman-centred care. Midwives play an important role in supporting these women. Women's need for midwifery-support increases as the time spent in latent phase increases. Copyright © 2015 Elsevier B.V. All rights reserved.

Tratamento da tuberculose de infecção latente: As recomendações actuais Latent tuberculosis infection treatment: Current recommendations

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R Duarte

2010-09-01

Full Text Available O diagnóstico e tratamento da infecção latente por Mycobacterium tuberculosis reduz significativamente o risco de desenvolvimento de tuberculose activa e a transmissão da doença na comunidade. O rastreio da tuberculose infecção latente deve passar pela exclusão de doença activa (inquérito de sintomas e radiografia pulmonar e avaliação da resposta imunológica ao M. tuberculosis através dos testes actualmente ao dispor, como o teste tuberculínico e os testes IGRA (interferon-gamma release assay. A escolha do esquema de tratamento deve ter em linha de conta a eficácia, a adesão e os efeitos colaterais associados ao mesmo Este documento actualiza as recomendações sobre tratamento da tuberculose infecção latente. São apresentadas indicações sobre quem deve ser rastreado e revistos os esquemas de tratamento.Diagnosis and treatment of latent infection with Mycobacterium tuberculosis (LTBI, significantly reduces the risk of developing active tuberculosis and the transmission of the disease in the community. LTBI screening must pass by the exclusion of active disease (symptoms enquiry and chest radiography and assessment of immune response to Mycobacterium tuberculosis testing with the tests currently available - tuberculin skin test and interferon-gamma release assay (IGRA. The choice of treatment must take into account the efficacy and side effects associated with the same. This document provides updated recommendations on latent tuberculosis infection treatment. Topics covered include whom to test for TB and reviewed LTBI treatment regimens.

Calculating latent frequencies of systems with local damping

International Nuclear Information System (INIS)

Kolonits, Ferenc

2005-01-01

Modal analysis of damped systems often cannot proceed with common real-eigenvalue techniques. The system of equilibrium equations leads to a matrix with elements being quadratic functions of a parameter λ. The values of that which make the matrix singular are the latent roots, while the solutions of the associated homogenous equation are the latent vectors. They are the (generally complex) characteristic frequencies and the mode shapes of the system, respectively. Although the theory is well developed, the numerical application is open to refinements yet. A reduction to better-known real-domain subtasks deserves attention. With a theorem of Popper and Gaspar, a n x n λ-matrix problem can be cut in two: into n-size asymmetric real matrices having as eigenvalues the n lower and n upper latent roots, ranked by absolute value. This approach may be of use for systems with high number of degrees of freedom while damped by a relatively few concentrated devices. It might fit also an earthquake analysis, where the lower portion of eigenvalues is customarily what counts. The dampers appear in the splitting algorithm as restricted-size modifications, ready for use by the Sherman-Morrison-Woodbury identity. The task is re-traced this way to a more usual real-asymmetric eigenproblem. A requirement of convergence is that the lower and upper n-set of latent values must be distinct. With odd-number degrees of freedom and neither over-damped, i.e. all latent roots being complex, this condition is surely violated. For such cases, a supplemental algorithm is proposed

Behaviorism, latent learning, and cognitive maps: needed revisions in introductory psychology textbooks.

Science.gov (United States)

Jensen, Robert

2006-01-01

This paper critically assesses the scholarship in introductory psychology textbooks in relation to the topic of latent learning. A review of the treatment of latent learning in 48 introductory psychology textbooks published between 1948 and 2004, with 21 of these texts published since 1999, reveals that the scholarship on the topic of latent learning demonstrated in introductory textbooks warrants improvement. Errors that persist in textbooks include the assertion that the latent learning experiments demonstrate unequivocally that reinforcement was not necessary for learning to occur, that behavioral theories could not account for the results of the latent learning experiments, that B. F. Skinner was an S-R association behaviorist who argued that reinforcement is necessary for learning to occur, and that because behavioral theories (including that of B. F. Skinner) were unable explain the results of the latent learning experiments the cognitive map invoked by Edward Tolman is the only explanation for latent learning. Finally, the validity of the cognitive map is typically accepted without question. Implications of the presence of these errors for students and the discipline are considered. Lastly, remedies are offered to improve the scholarship found in introductory psychology textbooks.

Generalized latent variable modeling multilevel, longitudinal, and structural equation models

CERN Document Server

Skrondal, Anders; Rabe-Hesketh, Sophia

2004-01-01

This book unifies and extends latent variable models, including multilevel or generalized linear mixed models, longitudinal or panel models, item response or factor models, latent class or finite mixture models, and structural equation models.

Preclinical validation of the hypoxia tracer 2-(2-nitroimidazol-1-yl)-N-(3,3,3-[18F]trifluoropropyl)acetamide, [18F]EF3

International Nuclear Information System (INIS)

Mahy, P.; De Bast, M.; Gregoire, V.; Leveque, P.H.; Gillart, J.; Labar, D.; Marchand, J.

2004-01-01

The 2-nitroimidazole derivative 2-(2-nitroimidazol-1-yl)-N-(3,3,3-trifluoropropyl)acetamide (EF3) is a marker which forms adducts into hypoxic cells. Radiosynthesis of [ 18 F]EF3 was recently performed by our group. Our aim was to study the pharmacokinetics, biodistribution, metabolism and specificity for hypoxia of [ 18 F]EF3. MCa-4, SCC VII, NFSA, FSA, FSA II or Sa-NH tumour-bearing C3H mice were injected intravenously with [ 18 F]EF3 and allowed to breathe air, 10% O 2 or carbogen until sacrifice 5-770 min after injection. Radioactivity was measured ex vivo in various organs, including urine and faeces. Selected organs were additionally processed to measure tracer metabolites with high-performance liquid chromatography. The half-life in blood was 73.9 min. [ 18 F]EF3 was eliminated mainly via the kidneys, with 75% of the injected activity found in the urine by 12 h 50 min. The biodistribution was fast and homogeneous except in the brain and the bone, where it was significantly lower, and in the liver and the kidney, where it was significantly higher. In most organs, the exceptions being the gastrointestinal and urinary tract, tissue-to-blood ratios were below or close to unity. In tumours, a relative accumulation of the tracer was observed with time, which, at 220 min after injection, depended on tumour strain and oxygenation conditions, i.e. 10% O 2 significantly increased the tumour-to-muscle ratio whereas carbogen decreased it. [ 18 F]EF3 was rapidly metabolised in the kidney and the liver. [ 18 F]EF3 is a promising tracer for detection of tumour hypoxia. A phase I study in head and neck cancer patients is in progress at our institution. (orig.)

Latent Class Analysis of Criminal Social Identity in a Prison Sample

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Boduszek Daniel

2014-06-01

Full Text Available This study aimed to examine the number of latent classes of criminal social identity that exist among male recidivistic prisoners. Latent class analysis was used to identify homogeneous groups of criminal social identity. Multinomial logistic regression was used to interpret the nature of the latent classes, or groups, by estimating the associationsto number of police arrests, recidivism, and violent offending while controlling for current age. The best fitting latent class model was a five-class solution: ‘High criminal social identity’ (17%, ‘High Centrality, Moderate Affect, Low Ties’ (21.7%, ‘Low Centrality, Moderate Affect, High Ties’ (13.3%,‘Low Cognitive, High Affect, Low Ties’ (24.6%, and ‘Low criminal social identity’ (23.4%. Each of the latent classes was predicted by differing external variables. Criminal social identity is best explained by five homogenous classes that display qualitative and quantitative differences.

Engineering recombinant EF-hand peptides for selective uranium uptake

Energy Technology Data Exchange (ETDEWEB)

Berthomieu, C.; Pardoux, R.; Beccia, M.R.; Lemaire, D.; Sauge-Merle, S. [CEA, DSV, IBEB, UMR7265 CNRS CEA Aix-Marseille Univ. (France); Guilbaud, P. [CEA, DRCPC, SMCS, LILA (France); Delangle, P. [CEA, INAC, Service de Chimie Inorganique et Biologique (France)

2014-07-01

In spite of an increasing number of publications in recent years, information regarding the mechanism of uranium interaction with proteins at the molecular level is limited and few quantitative studies have investigated the binding properties of uranyl with proteins or peptides. It is thus of great interest to better characterize these interactions, and to analyze structural factors governing uranyl binding and thermodynamic stabilization in proteins. Research in this direction will benefit our understanding of the molecular factors governing uranyl toxicity and speciation in cells and will also aid in developing new molecules for selectively binding uranium that could be used for uranium bioremediation purposes. Uranyl coordination properties have similarities with those of calcium, i.e electrostatic interactions preferentially with hard donor oxygen ligands and pentagonal bipyramidal structures. The EF-hand structural motif is the most prevalent Ca2{sup +-}binding site in proteins and is very appealing to analyse uranyl binding properties and develop affine and specific uranyl binding sites for biotechnology approaches. We selected the recombinant N-terminal domain of calmodulin from A. thaliana as a structured template that contains two EF-hand motifs (site I and site II) to analyze its uranyl binding properties and to engineer peptide variants with increased uranyl affinity and specificity. We showed that both site I and site II bind uranyl, with a dissociation constant in the nano-molar range for site I (K{sub d} ≅ 25 nM at pH 6). Using in vitro phosphorylation of a threonine located in the uranyl binding loop, we measured how adding a phosphoryl group affects the calcium and uranium binding affinities. The phosphorylated peptide exhibited a very large affinity for uranyl at pH 7, with a dissociation constant in the sub-nano-molar range K{sub d} = 0.25 ±0.06 nM, and FTIR analysis demonstrated that the phosphoryl group plays a determining role in uranyl

A competitive enzyme immunoassay for the quantitative detection of cocaine from banknotes and latent fingermarks.

Science.gov (United States)

van der Heide, Susan; Garcia Calavia, Paula; Hardwick, Sheila; Hudson, Simon; Wolff, Kim; Russell, David A

2015-05-01

A sensitive and versatile competitive enzyme immunoassay (cEIA) has been developed for the quantitative detection of cocaine in complex forensic samples. Polyclonal anti-cocaine antibody was purified from serum and deposited onto microtiter plates. The concentration of the cocaine antibody adsorbed onto the plates, and the dilution of the cocaine-HRP hapten were both studied to achieve an optimised immunoassay. The method was successfully used to quantify cocaine in extracts taken from both paper currency and latent fingermarks. The limit of detection (LOD) of 0.162ngmL(-1) achieved with the assay compares favourably to that of conventional chromatography-mass spectroscopy techniques, with an appropriate sensitivity for the quantification of cocaine at the low concentrations present in some forensic samples. The cEIA was directly compared to LC-MS for the analysis of ten UK banknote samples. The results obtained from both techniques were statistically similar, suggesting that the immunoassay was unaffected by cross-reactivity with potentially interfering compounds. The cEIA was used also for the detection of cocaine in extracts from latent fingermarks. The results obtained were compared to the cocaine concentrations detected in oral fluid sampled from the same individual. Using the cEIA, we have shown, for the first time, that endogeneously excreted cocaine can be detected and quantified from a single latent fingermark. Additionally, it has been shown that the presence of cocaine, at similar concentrations, in more than one latent fingermark from the same individual can be linked with those concentrations found in oral fluid. These results show that detection of drugs in latent fingermarks could directly indicate whether an individual has consumed the drug. The specificity and feasibility of measuring low concentrations of cocaine in complex forensic samples demonstrate the effectiveness and robustness of the assay. The immunoassay presents a simple and cost

Current management options for latent tuberculosis: a review

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Norton BL

2012-11-01

Full Text Available Brianna L Norton, David P HollandDepartment of Medicine, Division of Infectious Diseases, Duke University Medical Center, Durham, NC, USAAbstract: Tuberculosis remains the world’s second leading infectious cause of death, with nearly one-third of the global population latently infected. Treatment of latent tuberculosis infection is a mainstay of tuberculosis-control efforts in low-to medium-incidence countries. Isoniazid monotherapy has been the standard of care for decades, but its utility is impaired by poor completion rates. However, new, shorter-course regimens using rifamycins improve completion rates and are cost-saving compared with standard isoniazid monotherapy. We review the currently available therapies for latent tuberculosis infection and their toxicities and include a brief economic comparison of the different regimens.Keywords: isoniazid, rifampin, rifapentine, tuberculin skin test, interferon-gamma release assay

Harry Potter and the sorcerer's scope: latent scope biases in explanatory reasoning.

Science.gov (United States)

Khemlani, Sangeet S; Sussman, Abigail B; Oppenheimer, Daniel M

2011-04-01

What makes a good explanation? We examine the function of latent scope, i.e., the number of unobserved phenomena that an explanation can account for. We show that individuals prefer narrow latent scope explanations-those that account for fewer unobserved effects-to broader explanations. In Experiments 1a-d, participants found narrow latent scope explanations to be both more satisfying and more likely. In Experiment 2 we directly manipulated base rate information and again found a preference for narrow latent scope explanations. Participants in Experiment 3 evaluated more natural explanations of unexpected observations, and again displayed a bias for narrow latent scope explanations. We conclude by considering what this novel bias tells us about how humans evaluate explanations and engage in causal reasoning.

Site of ADP-ribosylation and the RNA-binding site are situated in different domains of the elongation factor EF-2

International Nuclear Information System (INIS)

Davydova, E.K.

1987-01-01

One of the proteins participating in the process of elongation of polypeptide chains - elongation factor 2 (EF-2) - can be ADP-ribosylated at a unique amino acid residue - diphthamide. Since the ADP-ribosylation of EF-2 at dipthamide leads to a loss of affinity of the factor for RNA while the presence of RNA inhibits the ADP-ribosylation reaction, it seemed probable to the authors that diphthamide participated directly in the binding of EF-2 to DNA. The experiments presented in this article showed that this was not the case: diphthamide and the RNA-binding site are situated on different domains of EF-2. Thus, ADP-ribosylation of factor EF-2 in one domain leads to a loss of the ability to bind to RNA in the other. The authors investigated the mutual arrangement of diphthamide and the RNA-binding site on the EF-2 molecule by preparing a factor from rabbit reticulocytes and subjecting it to proteolytic digestion with elastase. The factor was incubated with elastase for 15 min at 37 0 C at an enzyme:substrate ratio of 1:100 in buffer solution containing 20 mM Tris-HCl, pH 7.6, 10 mM KCl, 1 mM MgCl 2 , and 2 mM dithiothreitol. The reaction was stopped by adding para-methylsulfonyl fluoride to 50 micro-M. The authors obtained a preparation as a result of proteolysis and applied it on a column with RNA-Sepharose and separated into two fractions: RNA-binding and without affinity for RNA. The initial preparation and its fractions were subjected to exhaustive ADP-ribosylation in the presence of diphtheria toxin and [U- 14 C] nicotinaide adenine dinucleotide ([ 14 C]NAD) (296 mCi/mmole). The samples were analyzed electrophoretically in a polyacrylamide gel gradient in the presence of sodium dodecyl sulfate. For the detection of [ 14 C] ADP-ribosylated components, the gels were dried and exposed with RM-V x-ray film

Dynamic Latent Classification Model

DEFF Research Database (Denmark)

Zhong, Shengtong; Martínez, Ana M.; Nielsen, Thomas Dyhre

as possible. Motivated by this problem setting, we propose a generative model for dynamic classification in continuous domains. At each time point the model can be seen as combining a naive Bayes model with a mixture of factor analyzers (FA). The latent variables of the FA are used to capture the dynamics...

Understanding the fouling of UF/MF hollow fibres of biologically treated wastewaters using advanced EfOM characterization and statistical tools

KAUST Repository

Filloux, Emmanuelle

2012-08-01

Five secondary effluents and a river water source were characterized using size exclusion chromatography (LC-OCD-UVD-OND) and emission-excitation matrix (EEM) fluorescence spectroscopy in order to identify the major effluent organic matter (EfOM) fractions responsible for membrane fouling. This study showed the feasibility of coupling fluorescence EEM and LC-OCD-UVD-OND to investigate the fouling potential as well as a means to differentiate natural organic matter (NOM) from EfOM. The secondary effluents and river water showed a significant difference in organic matter characteristics and fouling potential, highlighting the importance of biological processes and the feed water source on EfOM characteristics and fouling potential. On the basis of statistical analysis, protein-like substances were found to be highly correlated to the fouling potential of secondary effluents. © 2012 Elsevier Ltd.

Understanding the fouling of UF/MF hollow fibres of biologically treated wastewaters using advanced EfOM characterization and statistical tools

KAUST Repository

Filloux, Emmanuelle; Labanowski, Jé rô me; Croue, Jean-Philippe

2012-01-01

Five secondary effluents and a river water source were characterized using size exclusion chromatography (LC-OCD-UVD-OND) and emission-excitation matrix (EEM) fluorescence spectroscopy in order to identify the major effluent organic matter (EfOM) fractions responsible for membrane fouling. This study showed the feasibility of coupling fluorescence EEM and LC-OCD-UVD-OND to investigate the fouling potential as well as a means to differentiate natural organic matter (NOM) from EfOM. The secondary effluents and river water showed a significant difference in organic matter characteristics and fouling potential, highlighting the importance of biological processes and the feed water source on EfOM characteristics and fouling potential. On the basis of statistical analysis, protein-like substances were found to be highly correlated to the fouling potential of secondary effluents. © 2012 Elsevier Ltd.

Tuberculosis and latent tuberculosis infection among healthcare workers in Kisumu, Kenya.

Science.gov (United States)

Agaya, Janet; Nnadi, Chimeremma D; Odhiambo, Joseph; Obonyo, Charles; Obiero, Vincent; Lipke, Virginia; Okeyo, Elisha; Cain, Kevin; Oeltmann, John E

2015-12-01

To assess prevalence and occupational risk factors of latent TB infection and history of TB disease ascribed to work in a healthcare setting in western Kenya. We conducted a cross-sectional survey among healthcare workers in western Kenya in 2013. They were recruited from dispensaries, health centres and hospitals that offer both TB and HIV services. School workers from the health facilities' catchment communities were randomly selected to serve as the community comparison group. Latent TB infection was diagnosed by tuberculin skin testing. HIV status of participants was assessed. Using a logistic regression model, we determined the adjusted odds of latent TB infection among healthcare workers compared to school workers; and among healthcare workers only, we assessed work-related risk factors for latent TB infection. We enrolled 1005 healthcare workers and 411 school workers. Approximately 60% of both groups were female. A total of 22% of 958 healthcare workers and 12% of 392 school workers tested HIV positive. Prevalence of self-reported history of TB disease was 7.4% among healthcare workers and 3.6% among school workers. Prevalence of latent TB infection was 60% among healthcare workers and 48% among school workers. Adjusted odds of latent TB infection were 1.5 times higher among healthcare workers than school workers (95% confidence interval 1.2-2.0). Healthcare workers at all three facility types had similar prevalence of latent TB infection (P = 0.72), but increasing years of employment was associated with increased odds of LTBI (P Kenya which offer TB and HIV services are at increased risk of latent TB infection, and the risk is similar across facility types. Implementation of WHO-recommended TB infection control measures are urgently needed in health facilities to protect healthcare workers. © 2015 John Wiley & Sons Ltd.

A Multinomial Probit Model with Latent Factors

DEFF Research Database (Denmark)

Piatek, Rémi; Gensowski, Miriam

2017-01-01

be meaningfully linked to an economic model. We provide sufficient conditions that make this structure identified and interpretable. For inference, we design a Markov chain Monte Carlo sampler based on marginal data augmentation. A simulation exercise shows the good numerical performance of our sampler......We develop a parametrization of the multinomial probit model that yields greater insight into the underlying decision-making process, by decomposing the error terms of the utilities into latent factors and noise. The latent factors are identified without a measurement system, and they can...

Vurdering af effekten af en vindmøllepark ved Overgaard på forekomsten af fugle i EF-fuglebeskyttelsesområde nr. 15

DEFF Research Database (Denmark)

Clausen, P.; Larsen, J. K.

forekomsten af en række arter der enten yngler eller raster inden for EF-fuglebeskyttelsesområdet, og er omfattet af EF-fuglebeskyttelsesdirektivets bilag I. Det drejer sig om arterne skarv Phalacrocorax carbo sinensis, blå kærhøg Circus cyaneus, hjejle Pluvialis apricaria, brushane Philomachus pugnax, klyde...

Reduction of Non-stationary Noise using a Non-negative Latent Variable Decomposition

DEFF Research Database (Denmark)

Schmidt, Mikkel Nørgaard; Larsen, Jan

2008-01-01

We present a method for suppression of non-stationary noise in single channel recordings of speech. The method is based on a non-negative latent variable decomposition model for the speech and noise signals, learned directly from a noisy mixture. In non-speech regions an over complete basis...... is learned for the noise that is then used to jointly estimate the speech and the noise from the mixture. We compare the method to the classical spectral subtraction approach, where the noise spectrum is estimated as the average over non-speech frames. The proposed method significantly outperforms...

Original article Latent classes of criminal intent associated with criminal behaviour

Directory of Open Access Journals (Sweden)

Daniel Boduszek

2014-07-01

Full Text Available Background This study aimed to examine the number of latent classes of criminal intent that exist among prisoners and to look at the associations with recidivism, number of police arrests, type of offending (robbery, violent offences, murder, and multiple offences, and age. Participants and procedure Latent class analysis was used to identify homogeneous subgroups of prisoners based on their responses to the 10 questions reflecting criminal intent. Participants were 309 male recidivistic prisoners incarcerated in a maximum security prison. Multinomial logistic regression was used to interpret the nature of the latent classes, or groups, by estimating the association between recidivism and latent classes of criminal intent while controlling for offence type (robbery, violent offences, murder, and multiple offences, number of arrests, and age. Results The best fitting latent class model was a three-class solution: ‘High criminal intent’ (49.3%, ‘Intermediate criminal intent’ (41.3%, and ‘Low criminal intent’ (9.4%. The latent classes were differentially related to the external variables (recidivism, violent offences, and age. Conclusions Criminal intent is best explained by three homogeneous classes that appear to represent an underlying continuum. Future work is needed to identify whether these distinct classes of criminal intent may predict engagement in various types of criminal behaviour.

Velocity ratio predicts outcomes in patients with low gradient severe aortic stenosis and preserved EF

DEFF Research Database (Denmark)

Jander, Nikolaus; Hochholzer, Willibald; Kaufmann, Beat A

2014-01-01

OBJECTIVE: To evaluate the usefulness of velocity ratio (VR) in patients with low gradient severe aortic stenosis (LGSAS) and preserved EF. BACKGROUND: LGSAS despite preserved EF represents a clinically challenging entity. Reliance on mean pressure gradient (MPG) may underestimate stenosis severity...... for severe stenosis. We hypothesised that VR may have conceptual advantages over MPG and AVA, predict clinical outcomes and thereby be useful in the management of patients with LGSAS. METHODS: Patients from the prospective Simvastatin and Ezetimibe in Aortic Stenosis (SEAS) study with an AVA...≤40 mm Hg and EF≥55% and asymptomatic at baseline were stratified according to VR with a cut-off value of 0.25. Outcomes were evaluated according to aortic valve-related events and cardiovascular death. RESULTS: Of 435 patients with LGSAS, 197 (45%) had VRVR≥0...

Competing risk model for reduction in life expectancy from radiogenic latent cancer

International Nuclear Information System (INIS)

Davis, H.T.

1978-01-01

Because of the large number of persons who could potentially receive low doses of radiation as a result of a nuclear reactor accident, the number of fatalities from latent cancers is generally larger than the early, or prompt, fatalities. For this reason the latent cancer fatality risk of reactor accidents is perceived as being more important than the early fatality risk. In addition, there exists the temptation to add the latent cancer fatality risk to the early fatality risk for the purpose of comparing reactor accident risks to other risks that society is exposed to, such as automobile accidents, airplane accidents, hurricanes, etc. However, the impact on the individual, and society as a whole, due to latent cancer fatalities is significantly different from the impact produced by early fatalities. Early fatalities generally result in appreciable life shortening for the affected individual while latent cancer fatalities generally result in very limited life shortening. A mathematical model was developed to express the reduction in life expectancy due to latent radiogenic cancer as a function of dose received

PET CT Identifies Reactivation Risk in Cynomolgus Macaques with Latent M. tuberculosis.

Directory of Open Access Journals (Sweden)

Philana Ling Lin

2016-07-01

Full Text Available Mycobacterium tuberculosis infection presents across a spectrum in humans, from latent infection to active tuberculosis. Among those with latent tuberculosis, it is now recognized that there is also a spectrum of infection and this likely contributes to the variable risk of reactivation tuberculosis. Here, functional imaging with 18F-fluorodeoxygluose positron emission tomography and computed tomography (PET CT of cynomolgus macaques with latent M. tuberculosis infection was used to characterize the features of reactivation after tumor necrosis factor (TNF neutralization and determine which imaging characteristics before TNF neutralization distinguish reactivation risk. PET CT was performed on latently infected macaques (n = 26 before and during the course of TNF neutralization and a separate set of latently infected controls (n = 25. Reactivation occurred in 50% of the latently infected animals receiving TNF neutralizing antibody defined as development of at least one new granuloma in adjacent or distant locations including extrapulmonary sites. Increased lung inflammation measured by PET and the presence of extrapulmonary involvement before TNF neutralization predicted reactivation with 92% sensitivity and specificity. To define the biologic features associated with risk of reactivation, we used these PET CT parameters to identify latently infected animals at high risk for reactivation. High risk animals had higher cumulative lung bacterial burden and higher maximum lesional bacterial burdens, and more T cells producing IL-2, IL-10 and IL-17 in lung granulomas as compared to low risk macaques. In total, these data support that risk of reactivation is associated with lung inflammation and higher bacterial burden in macaques with latent Mtb infection.

Skin Resistivity Value of Upper Trapezius Latent Trigger Points

Directory of Open Access Journals (Sweden)

Elżbieta Skorupska

2015-01-01

Full Text Available Introduction. The skin resistivity (SkR measurement is commonly recommended for acupoints measurement, but for trigger points (TrPs only one study is available. The purpose of the study was to evaluate SkR for latent TrPs compared to non-TrPs and the surrounding tissue. Material and Methods. Forty-two healthy volunteers with unilateral latent upper trapezius TrPs (12 men, 30 women aged 21–23 (mean age: 22.1 ± 0.6 y participated in the study. Keithley electrometer 610B was used for measuring SkR (Ag/AgCl self-adhesive, disposable ground electrode: 30 mm diameter. SkR was measured for latent TrPs and compared to opposite non-TrPs sites and the surrounding tissue. Results. The SkR decrease of TrPs-positive sites as compared to TrPs-negative sites and the surrounding tissue was confirmed. However, no statistically significant difference in the SkR value occurred when all data were analyzed. The same was confirmed after gender division and for TrPs-positive subjects examined for referred pain and twitch response presence. Conclusion. SkR reactive changes at latent TrPs are possible but the results were not consistent with the previous study. Thus, caution in applying SkR to latent TrPs isolation is recommended and its clinical use should not be encouraged yet. Further studies, especially on active TrPs, are yet required.

Latent variable modeling%建立隐性变量模型

Institute of Scientific and Technical Information of China (English)

蔡力

2012-01-01

@@ A latent variable model, as the name suggests,is a statistical model that contains latent, that is, unobserved, variables.Their roots go back to Spearman's 1904 seminal work[1] on factor analysis,which is arguably the first well-articulated latent variable model to be widely used in psychology, mental health research, and allied disciplines.Because of the association of factor analysis with early studies of human intelligence, the fact that key variables in a statistical model are, on occasion, unobserved has been a point of lingering contention and controversy.The reader is assured, however, that a latent variable,defined in the broadest manner, is no more mysterious than an error term in a normal theory linear regression model or a random effect in a mixed model.

Accuracy of latent-variable estimation in Bayesian semi-supervised learning.

Science.gov (United States)

Yamazaki, Keisuke

2015-09-01

Hierarchical probabilistic models, such as Gaussian mixture models, are widely used for unsupervised learning tasks. These models consist of observable and latent variables, which represent the observable data and the underlying data-generation process, respectively. Unsupervised learning tasks, such as cluster analysis, are regarded as estimations of latent variables based on the observable ones. The estimation of latent variables in semi-supervised learning, where some labels are observed, will be more precise than that in unsupervised, and one of the concerns is to clarify the effect of the labeled data. However, there has not been sufficient theoretical analysis of the accuracy of the estimation of latent variables. In a previous study, a distribution-based error function was formulated, and its asymptotic form was calculated for unsupervised learning with generative models. It has been shown that, for the estimation of latent variables, the Bayes method is more accurate than the maximum-likelihood method. The present paper reveals the asymptotic forms of the error function in Bayesian semi-supervised learning for both discriminative and generative models. The results show that the generative model, which uses all of the given data, performs better when the model is well specified. Copyright © 2015 Elsevier Ltd. All rights reserved.

31P-magnetic resonance spectroscopy: Impaired energy metabolism in latent hyperthyroidism

International Nuclear Information System (INIS)

Theissen, P.; Kaldewey, S.; Moka, D.; Bunke, J.; Voth, E.; Schicha, H.

1993-01-01

31 Phosphorous magnetic resonance spectroscopy allows an in vivo examination of energy metabolism. The present study was designed to evaluate whether in patients with latent hyperthyroidism alterations of muscle energy metabolism could be found similar to those observed in patients with overt hyperthyroidism. In 10 patients with overt hyperthyroidism before therapy and 20 with latent hyperthyroidism (also without therapy) and in 24 healthy volunteers magnetic resonance spectroscopy of the calf muscle was performed within a 1.5-Tesla magnet. Muscle concentrations of phosphocreatine, inorganic phosphate, and ATP were quantified compared to an external standard solution of K 2 HPO 4 . In the patients with overt hyperthyroidism and with latent hyperthyroidism a significant decrease of phosphocreatine was found. Further, the ATP concentration in patients with latent and manifest hyperthyroidism tended towards lower values. There were no significant differences in the decrease of phosphocreatine and ATP between both patient groups. Therefore, this study for the first time shows that alterations of energy metabolism in latent hyperthyroidism can be measured and that they are similar to those observed in overt hyperthyroidism. (orig.) [de

Generalized correlation of latent heats of vaporization of coal liquid model compounds between their freezing points and critical points

Energy Technology Data Exchange (ETDEWEB)

Sivaraman, A.; Kobuyashi, R.; Mayee, J.W.

1984-02-01

Based on Pitzer's three-parameter corresponding states principle, the authors have developed a correlation of the latent heat of vaporization of aromatic coal liquid model compounds for a temperature range from the freezing point to the critical point. An expansion of the form L = L/sub 0/ + ..omega..L /sub 1/ is used for the dimensionless latent heat of vaporization. This model utilizes a nonanalytic functional form based on results derived from renormalization group theory of fluids in the vicinity of the critical point. A simple expression for the latent heat of vaporization L = D/sub 1/epsilon /SUP 0.3333/ + D/sub 2/epsilon /SUP 0.8333/ + D/sub 4/epsilon /SUP 1.2083/ + E/sub 1/epsilon + E/sub 2/epsilon/sup 2/ + E/sub 3/epsilon/sup 3/ is cast in a corresponding states principle correlation for coal liquid compounds. Benzene, the basic constituent of the functional groups of the multi-ring coal liquid compounds, is used as the reference compound in the present correlation. This model works very well at both low and high reduced temperatures approaching the critical point (0.02 < epsilon = (T /SUB c/ - T)/(T /SUB c/- 0.69)). About 16 compounds, including single, two, and three-ring compounds, have been tested and the percent root-mean-square deviations in latent heat of vaporization reported and estimated through the model are 0.42 to 5.27%. Tables of the coefficients of L/sub 0/ and L/sub 1/ are presented. The contributing terms of the latent heat of vaporization function are also presented in a table for small increments of epsilon.

Photodynamic inactivation of rubella virus enhances recombination with a latent virus of a baby hamster kidney cell line BHK21

International Nuclear Information System (INIS)

Yamamoto, Nobuto; Urade, Masahiro

1989-01-01

Rubella virus is very sensitive to photodynamic action. When tested with 1.2 x 10 -5 M toluidine blue and 8 W fluorescent lamp at a fluence of 11 W/m 2 , inactivation kinetics showed a linear single hit curve with a k value of 1.48 min -1 . Photodynamic inactivation of rubella virus greatly enhanced recombination with a latent virus (R-virus) of baby hamster kidney BHK21 cells. In contrast, no hybrids were detected in lysates of the cells infected with either UV-treated or untreated rubella virus. Therefore, hybrid viruses were readily detected only in lysates of BHK21 cells infected with photodynamically treated rubella virus. Photodynamic damage of rubella virus genomes generated a new hybrid type (hybrid type 3) in addition to a previously described type 2 hybrid (formerly designated as HPV-RV variant). Although both of these hybrid types carry the CF antigens of rubella virus, plaque forming ability of type 3 hybrid is neutralized neither by anti-rubella serum nor by anti-latent virus serum while type 2 hybrid is neutralized by anti-latent virus serum. (author)

The fsr Quorum-Sensing System and Cognate Gelatinase Orchestrate the Expression and Processing of Proprotein EF_1097 into the Mature Antimicrobial Peptide Enterocin O16

OpenAIRE

Dundar, Halil; Brede, Dag A.; La Rosa, Sabina Leanti; El-Gendy, Ahmed Osama; Diep, Dzung B.; Nes, Ingolf F.

2015-01-01

A novel antimicrobial peptide designated enterocin O16 was purified from Enterococcus faecalis. Mass spectrometry showed a monoisotopic mass of 7,231 Da, and N-terminal Edman degradation identified a 29-amino-acid sequence corresponding to residues 90 to 119 of the EF_1097 protein. Bioinformatic analysis showed that enterocin O16 is composed of the 68 most C-terminal residues of the EF_1097 protein. Introduction of an in-frame isogenic deletion in the ef1097 gene abolished the production of e...

Latent class factor and cluster models, bi-plots and tri-plots and related graphical displays

NARCIS (Netherlands)

Magidson, J.; Vermunt, J.K.

2001-01-01

We propose an alternative method of conducting exploratory latent class analysis that utilizes latent class factor models, and compare it to the more traditional approach based on latent class cluster models. We show that when formulated in terms of R mutually independent, dichotomous latent

Latent uncertainties of the precalculated track Monte Carlo method

Energy Technology Data Exchange (ETDEWEB)

Renaud, Marc-André; Seuntjens, Jan [Medical Physics Unit, McGill University, Montreal, Quebec H3G 1A4 (Canada); Roberge, David [Département de radio-oncologie, Centre Hospitalier de l’Université de Montréal, Montreal, Quebec H2L 4M1 (Canada)

2015-01-15

Purpose: While significant progress has been made in speeding up Monte Carlo (MC) dose calculation methods, they remain too time-consuming for the purpose of inverse planning. To achieve clinically usable calculation speeds, a precalculated Monte Carlo (PMC) algorithm for proton and electron transport was developed to run on graphics processing units (GPUs). The algorithm utilizes pregenerated particle track data from conventional MC codes for different materials such as water, bone, and lung to produce dose distributions in voxelized phantoms. While PMC methods have been described in the past, an explicit quantification of the latent uncertainty arising from the limited number of unique tracks in the pregenerated track bank is missing from the paper. With a proper uncertainty analysis, an optimal number of tracks in the pregenerated track bank can be selected for a desired dose calculation uncertainty. Methods: Particle tracks were pregenerated for electrons and protons using EGSnrc and GEANT4 and saved in a database. The PMC algorithm for track selection, rotation, and transport was implemented on the Compute Unified Device Architecture (CUDA) 4.0 programming framework. PMC dose distributions were calculated in a variety of media and compared to benchmark dose distributions simulated from the corresponding general-purpose MC codes in the same conditions. A latent uncertainty metric was defined and analysis was performed by varying the pregenerated track bank size and the number of simulated primary particle histories and comparing dose values to a “ground truth” benchmark dose distribution calculated to 0.04% average uncertainty in voxels with dose greater than 20% of D{sub max}. Efficiency metrics were calculated against benchmark MC codes on a single CPU core with no variance reduction. Results: Dose distributions generated using PMC and benchmark MC codes were compared and found to be within 2% of each other in voxels with dose values greater than 20% of

Latent uncertainties of the precalculated track Monte Carlo method

International Nuclear Information System (INIS)

Renaud, Marc-André; Seuntjens, Jan; Roberge, David

2015-01-01

Purpose: While significant progress has been made in speeding up Monte Carlo (MC) dose calculation methods, they remain too time-consuming for the purpose of inverse planning. To achieve clinically usable calculation speeds, a precalculated Monte Carlo (PMC) algorithm for proton and electron transport was developed to run on graphics processing units (GPUs). The algorithm utilizes pregenerated particle track data from conventional MC codes for different materials such as water, bone, and lung to produce dose distributions in voxelized phantoms. While PMC methods have been described in the past, an explicit quantification of the latent uncertainty arising from the limited number of unique tracks in the pregenerated track bank is missing from the paper. With a proper uncertainty analysis, an optimal number of tracks in the pregenerated track bank can be selected for a desired dose calculation uncertainty. Methods: Particle tracks were pregenerated for electrons and protons using EGSnrc and GEANT4 and saved in a database. The PMC algorithm for track selection, rotation, and transport was implemented on the Compute Unified Device Architecture (CUDA) 4.0 programming framework. PMC dose distributions were calculated in a variety of media and compared to benchmark dose distributions simulated from the corresponding general-purpose MC codes in the same conditions. A latent uncertainty metric was defined and analysis was performed by varying the pregenerated track bank size and the number of simulated primary particle histories and comparing dose values to a “ground truth” benchmark dose distribution calculated to 0.04% average uncertainty in voxels with dose greater than 20% of D max . Efficiency metrics were calculated against benchmark MC codes on a single CPU core with no variance reduction. Results: Dose distributions generated using PMC and benchmark MC codes were compared and found to be within 2% of each other in voxels with dose values greater than 20% of the

A solar air collector with integrated latent heat thermal storage

Directory of Open Access Journals (Sweden)

Klimes Lubomir

2012-04-01

Full Text Available Simulations of the behaviour of a solar air collector with integrated latent heat thermal storage were performed. The model of the collector was created with the use of coupling between TRNSYS 17 and MATLAB. Latent heat storage (Phase Change Material - PCM was integrated with the solar absorber. The model of the latent heat storage absorber was created in MATLAB and the model of the solar air collector itself was created in TRNSYS with the use of TYPE 56. The model of the latent heat storage absorber allows specification of the PCM properties as well as other parameters. The simulated air collector was the front and back pass collector with the absorber in the middle of the air cavity. Two variants were considered for comparison; the light-weight absorber made of sheet metal and the heat-storage absorber with the PCM. Simulations were performed for the climatic conditions of the Czech Republic (using TMY weather data.

Joint resistance measurements of pancake and terminal joints for JT-60SA EF coils

Energy Technology Data Exchange (ETDEWEB)

Obana, Tetsuhiro, E-mail: obana.tetsuhiro@LHD.nifs.ac.jp [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Takahata, Kazuya; Hamaguchi, Shinji; Mito, Toshiyuki; Imagawa, Shinsaku [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Kizu, Kaname; Murakami, Haruyuki; Yoshida, Kiyoshi [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan)

2013-11-15

Highlights: • To evaluate the joint fabrication technology for the JT-60SA EF coils, joint resistance measurements were conducted with a joint sample. • The joint sample was composed of pancake and terminal joints. • The measurements demonstrated that both joints fulfilled the design requirement. • Considering the measurements, the characteristics of both joints were investigated using an analytical model that represents the joints. -- Abstract: To evaluate the joint fabrication technology for the JT-60SA EF coils, joint resistance measurements were conducted using a sample consisting of pancake and terminal joints. Both joints are shake-hands lap joints composed of cable-in-conduit conductors and a pure copper saddle-shaped spacer. The measurements demonstrated that both joints fulfilled the design requirement. Considering these measurements, the characteristics of both joints were investigated using analytical models that represent the joints. The analyses indicated that the characteristics of the conductors used in the joints affect the characteristics of the joints.

Empirically Defined Patterns of Executive Function Deficits in Schizophrenia and Their Relation to Everyday Functioning: A Person-Centered Approach

Science.gov (United States)

Iampietro, Mary; Giovannetti, Tania; Drabick, Deborah A. G.; Kessler, Rachel K.

2013-01-01

Executive function (EF) deficits in schizophrenia (SZ) are well documented, although much less is known about patterns of EF deficits and their association to differential impairments in everyday functioning. The present study empirically defined SZ groups based on measures of various EF abilities and then compared these EF groups on everyday action errors. Participants (n=45) completed various subtests from the Delis–Kaplan Executive Function System (D-KEFS) and the Naturalistic Action Test (NAT), a performance-based measure of everyday action that yields scores reflecting total errors and a range of different error types (e.g., omission, perseveration). Results of a latent class analysis revealed three distinct EF groups, characterized by (a) multiple EF deficits, (b) relatively spared EF, and (c) perseverative responding. Follow-up analyses revealed that the classes differed significantly on NAT total errors, total commission errors, and total perseveration errors; the two classes with EF impairment performed comparably on the NAT but performed worse than the class with relatively spared EF. In sum, people with SZ demonstrate variable patterns of EF deficits, and distinct aspects of these EF deficit patterns (i.e., poor mental control abilities) may be associated with everyday functioning capabilities. PMID:23035705

Arabidopsis EF-Tu receptor enhances bacterial disease resistance in transgenic wheat.

Science.gov (United States)

Schoonbeek, Henk-Jan; Wang, Hsi-Hua; Stefanato, Francesca L; Craze, Melanie; Bowden, Sarah; Wallington, Emma; Zipfel, Cyril; Ridout, Christopher J

2015-04-01

Perception of pathogen (or microbe)-associated molecular patterns (PAMPs/MAMPs) by pattern recognition receptors (PRRs) is a key component of plant innate immunity. The Arabidopsis PRR EF-Tu receptor (EFR) recognizes the bacterial PAMP elongation factor Tu (EF-Tu) and its derived peptide elf18. Previous work revealed that transgenic expression of AtEFR in Solanaceae confers elf18 responsiveness and broad-spectrum bacterial disease resistance. In this study, we developed a set of bioassays to study the activation of PAMP-triggered immunity (PTI) in wheat. We generated transgenic wheat (Triticum aestivum) plants expressing AtEFR driven by the constitutive rice actin promoter and tested their response to elf18. We show that transgenic expression of AtEFR in wheat confers recognition of elf18, as measured by the induction of immune marker genes and callose deposition. When challenged with the cereal bacterial pathogen Pseudomonas syringae pv. oryzae, transgenic EFR wheat lines had reduced lesion size and bacterial multiplication. These results demonstrate that AtEFR can be transferred successfully from dicot to monocot species, further revealing that immune signalling pathways are conserved across these distant phyla. As novel PRRs are identified, their transfer between plant families represents a useful strategy for enhancing resistance to pathogens in crops. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Hb taradale [beta82(EF6)Lys-->Arg]: a novel mutation at a 2,3-diphosphoglycerate binding site.

Science.gov (United States)

Brennan, Stephen O; Sheen, Campbell; Chan, Tim; George, Peter M

2005-01-01

Hb Taradale [beta82(EF6)Lys-->Arg] was initially detected as a split Hb A0 peak on Hb A1c, monitoring. Red cell parameters, hemoglobin (Hb) electrophoresis and stability tests were normal. Mass spectrometry (ms) clearly identified a variant beta chain with a mass increase of 28 Da and peptide mapping located the mutation site to peptide betaT-9. DNA sequencing confirmed the presence of a novel beta82(EF6)Lys-->Arg mutation. This conservative substitution at a 2,3-diphosphoglycerate (2,3-DPG) binding site did not, however, appear to affect the P50 for oxygen binding.

Latent class models for classification

NARCIS (Netherlands)

Vermunt, J.K.; Magidson, J.

2003-01-01

An overview is provided of recent developments in the use of latent class (LC) and other types of finite mixture models for classification purposes. Several extensions of existing models are presented. Two basic types of LC models for classification are defined: supervised and unsupervised

Piecewise Linear-Linear Latent Growth Mixture Models with Unknown Knots

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Kohli, Nidhi; Harring, Jeffrey R.; Hancock, Gregory R.

2013-01-01

Latent growth curve models with piecewise functions are flexible and useful analytic models for investigating individual behaviors that exhibit distinct phases of development in observed variables. As an extension of this framework, this study considers a piecewise linear-linear latent growth mixture model (LGMM) for describing segmented change of…

Rapid detection of drug metabolites in latent fingermarks.

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Hazarika, Pompi; Jickells, Sue M; Russell, David A

2009-01-01

Magnetic particles functionalised with anti-cotinine antibody have been used to image latent fingermarks through the detection of the cotinine antigen in the sweat deposited within the fingerprints of smokers. The antibody-magnetic particle conjugates are readily applied to latent fingerprints while excess reagents are removed through the use of a magnetic wand. The results have shown that drug metabolites, such as cotinine, can be detected and used to image the fingermark to establish the identity of an individual within 15 minutes.

Effects of latent toxoplasmosis on autoimmune thyroid diseases in pregnancy.

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Kaňková, Šárka; Procházková, Lucie; Flegr, Jaroslav; Calda, Pavel; Springer, Drahomíra; Potluková, Eliška

2014-01-01

Toxoplasmosis, one of the most common zoonotic diseases worldwide, can induce various hormonal and behavioural alterations in infected hosts, and its most common form, latent toxoplasmosis, influences the course of pregnancy. Autoimmune thyroid diseases (AITD) belong to the well-defined risk factors for adverse pregnancy outcomes. The aim of this study was to investigate whether there is a link between latent toxoplasmosis and maternal AITD in pregnancy. Cross-sectional study in 1248 consecutive pregnant women in the 9-12th gestational weeks. Serum thyroid-stimulating hormone (TSH), thyroperoxidase antibodies (TPOAb), and free thyroxine (FT4) were assessed by chemiluminescence; the Toxoplasma status was detected by the complement fixation test (CFT) and anti-Toxoplasma IgG enzyme-linked immunosorbent assay (ELISA). Overall, 22.5% of the women were positive for latent toxoplasmosis and 14.7% were screened positive for AITD. Women with latent toxoplasmosis had more often highly elevated TPOAb than the Toxoplasma-negative ones (p = 0.004), and latent toxoplasmosis was associated with decrease in serum TSH levels (p = 0.049). Moreover, we found a positive correlation between FT4 and the index of positivity for anti-Toxoplasma IgG antibodies (p = 0.033), which was even stronger in the TPOAb-positive Toxoplasma-positive women, (p = 0.014), as well as a positive correlation between FT4 and log2 CFT (p = 0.009). Latent toxoplasmosis was associated with a mild increase in thyroid hormone production in pregnancy. The observed Toxoplasma-associated changes in the parameters of AITD are mild and do not seem to be clinically relevant; however, they could provide new clues to the complex pathogenesis of autoimmune thyroid diseases.

Evaluation of left ventricular function and volume with multidetector-row computed tomography. Comparison with electrocardiogram-gated single photon emission computed tomography

International Nuclear Information System (INIS)

Suzuki, Takeya; Yamashina, Shohei; Nanjou, Shuji; Yamazaki, Junichi

2007-01-01

This study compared left ventricular systolic function and volume determined by multidetector-row computed tomography (MDCT) and electrocardiogram-gated single photon emission computed tomography (G-SPECT) Thirty-seven patients with coronary artery disease and non-cardiovascular disease underwent MDCT. In this study, left ventricular ejection fraction (EF), left ventricular end-diastolic volume (EDV) and left ventricular end-systolic volume (ESV) were calculated using only two-phase imaging with MDCT. Left ventricular function and volume were compared using measurements from G-SPECT. We conducted MDCT and G-SPECT virtually simultaneously. Both the EF and ESV evaluated by MDCT closely correlated with G-SPECT (r=0.763, P 65 bpm) during MDCT significantly influenced the difference in EF calculated from MDCT and G-SPECT (P<0.05). Left ventricular function can be measured with MDCT as well as G-SPECT. However, a heart rate over 65 bpm during MDCT negatively affects the EF correlation between MDCT and G-SPECT. (author)

Efímero Festín, el video danza antártico

OpenAIRE

Pombo, Ernesto; Costa Chimene

2013-01-01

Efímero Festín es un video danza pensado específicamente para ser realizado en la Antártida argentina. Pretende a través del arte y de una forma poética, colaborar con la concientización del cuidado del medio ambiente.

Latent effectiveness of desiccant wheel: A silica gels- water system

International Nuclear Information System (INIS)

Rabah, A. A.; Mohamed, S. A.

2009-01-01

A latent heat effectiveness model in term of dimensionless groups? =f (NTU, m * ,Crm * ) for energy wheel has been analytically derived. The energy wheel is divided into humidification and dehumidification sections. For each section macroscopic mass differential equations for gas and the matrix were applied. In this process local latent effectiveness (? c ,? h ) for the humidification and dehumidification section of the wheel were obtained. The Latent effectiveness of the wheel is then derived form local effectiveness [? =f (? c ,? h)]. The model is compared with the existing experimental investigation and manufacturer data for energy wheel. More than 90% of the experimental data within a confidence limit of 95%. (Author)

Intercept Centering and Time Coding in Latent Difference Score Models

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Grimm, Kevin J.

2012-01-01

Latent difference score (LDS) models combine benefits derived from autoregressive and latent growth curve models allowing for time-dependent influences and systematic change. The specification and descriptions of LDS models include an initial level of ability or trait plus an accumulation of changes. A limitation of this specification is that the…

Large-scale weakly supervised object localization via latent category learning.

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Chong Wang; Kaiqi Huang; Weiqiang Ren; Junge Zhang; Maybank, Steve

2015-04-01

Localizing objects in cluttered backgrounds is challenging under large-scale weakly supervised conditions. Due to the cluttered image condition, objects usually have large ambiguity with backgrounds. Besides, there is also a lack of effective algorithm for large-scale weakly supervised localization in cluttered backgrounds. However, backgrounds contain useful latent information, e.g., the sky in the aeroplane class. If this latent information can be learned, object-background ambiguity can be largely reduced and background can be suppressed effectively. In this paper, we propose the latent category learning (LCL) in large-scale cluttered conditions. LCL is an unsupervised learning method which requires only image-level class labels. First, we use the latent semantic analysis with semantic object representation to learn the latent categories, which represent objects, object parts or backgrounds. Second, to determine which category contains the target object, we propose a category selection strategy by evaluating each category's discrimination. Finally, we propose the online LCL for use in large-scale conditions. Evaluation on the challenging PASCAL Visual Object Class (VOC) 2007 and the large-scale imagenet large-scale visual recognition challenge 2013 detection data sets shows that the method can improve the annotation precision by 10% over previous methods. More importantly, we achieve the detection precision which outperforms previous results by a large margin and can be competitive to the supervised deformable part model 5.0 baseline on both data sets.

Reliability measures in item response theory: manifest versus latent correlation functions.

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Milanzi, Elasma; Molenberghs, Geert; Alonso, Ariel; Verbeke, Geert; De Boeck, Paul

2015-02-01

For item response theory (IRT) models, which belong to the class of generalized linear or non-linear mixed models, reliability at the scale of observed scores (i.e., manifest correlation) is more difficult to calculate than latent correlation based reliability, but usually of greater scientific interest. This is not least because it cannot be calculated explicitly when the logit link is used in conjunction with normal random effects. As such, approximations such as Fisher's information coefficient, Cronbach's α, or the latent correlation are calculated, allegedly because it is easy to do so. Cronbach's α has well-known and serious drawbacks, Fisher's information is not meaningful under certain circumstances, and there is an important but often overlooked difference between latent and manifest correlations. Here, manifest correlation refers to correlation between observed scores, while latent correlation refers to correlation between scores at the latent (e.g., logit or probit) scale. Thus, using one in place of the other can lead to erroneous conclusions. Taylor series based reliability measures, which are based on manifest correlation functions, are derived and a careful comparison of reliability measures based on latent correlations, Fisher's information, and exact reliability is carried out. The latent correlations are virtually always considerably higher than their manifest counterparts, Fisher's information measure shows no coherent behaviour (it is even negative in some cases), while the newly introduced Taylor series based approximations reflect the exact reliability very closely. Comparisons among the various types of correlations, for various IRT models, are made using algebraic expressions, Monte Carlo simulations, and data analysis. Given the light computational burden and the performance of Taylor series based reliability measures, their use is recommended. © 2014 The British Psychological Society.

Latent factors and route choice behaviour

DEFF Research Database (Denmark)

Prato, Carlo Giacomo

. A reliable dataset was prepared through measures of internal consistency and sampling adequacy, and data were analyzed with a proper application of factor analysis to the route choice context. For the dataset obtained from the survey, six latent constructs affecting driver behaviour were extracted and scores...... on each factor for each survey participant were calculated. Path generation algorithms were examined with respect to observed behaviour, through a measure of reproduction with deterministic techniques of the routes indicated in the answers to the survey. Results presented evidence that the majority...... and Link Nested Logit. Estimates were produced from model specifications that considered level-of-service, label and facility dummy variables. Moreover, a modelling framework was designed to represent drivers’ choices as affected by the latent constructs extracted with factor analysis. Previous experience...

A single exercise bout augments adenovirus-specific T-cell mobilization and function.

Science.gov (United States)

Kunz, Hawley E; Spielmann, Guillaume; Agha, Nadia H; O'Connor, Daniel P; Bollard, Catherine M; Simpson, Richard J

2018-04-30

Adoptive transfer of virus-specific T-cells (VSTs) effectively treats viral infections following allogeneic hematopoietic stem cell transplantation (alloHSCT), but logistical difficulties have limited widespread availability of VSTs as a post-transplant therapeutic. A single exercise bout mobilizes VSTs specific for latent herpesviruses (i.e. CMV and EBV) to peripheral blood and augments their ex vivo expansion. We investigated whether exercise exerts similar effects on T-cells specific for a NON-latent virus such as adenovirus, which is a major contributor to infection-related morbidity and mortality after alloHSCT. Thirty minutes of cycling exercise increased circulating adenovirus-specific T-cells 2.0-fold and augmented their ex vivo expansion by ~33% compared to rest without altering antigen and MHC-specific autologous target cell killing capabilities. We conclude that exercise is a simple and economical adjuvant to boost the isolation and manufacture of therapeutic VSTs specific to latent and non-latent viruses from healthy donors. Copyright © 2018. Published by Elsevier Inc.

A Taxonomy of Latent Structure Assumptions for Probability Matrix Decomposition Models.

Science.gov (United States)

Meulders, Michel; De Boeck, Paul; Van Mechelen, Iven

2003-01-01

Proposed a taxonomy of latent structure assumptions for probability matrix decomposition (PMD) that includes the original PMD model and a three-way extension of the multiple classification latent class model. Simulation study results show the usefulness of the taxonomy. (SLD)

Rapid visualization of latent fingermarks using gold seed-mediated enhancement

Directory of Open Access Journals (Sweden)

Chia-Hao Su

2016-11-01

Full Text Available Abstract Background Fingermarks are one of the most important and useful forms of physical evidence in forensic investigations. However, latent fingermarks are not directly visible, but can be visualized due to the presence of other residues (such as inorganic salts, proteins, polypeptides, enzymes and human metabolites which can be detected or recognized through various strategies. Convenient and rapid techniques are still needed to provide obvious contrast between the background and the fingermark ridges and to then visualize latent fingermark with a high degree of selectivity and sensitivity. Results In this work, lysozyme-binding aptamer-conjugated Au nanoparticles (NPs are used to recognize and target lysozyme in the fingermark ridges, and Au+-complex solution is used as a growth agent to reduce Au+ from Au+ to Au0 on the surface of the Au NPs. Distinct fingermark patterns were visualized on a range of professional forensic within 3 min; the resulting images could be observed by the naked eye without background interference. The entire processes from fingermark collection to visualization only entails two steps and can be completed in less than 10 min. The proposed method provides cost and time savings over current fingermark visualization methods. Conclusions We report a simple, inexpensive, and fast method for the rapid visualization of latent fingermarks on the non-porous substrates using Au seed-mediated enhancement. Au seed-mediated enhancement is used to achieve the rapid visualization of latent fingermarks on non-porous substrates by the naked eye without the use of expensive or sophisticated instruments. The proposed approach offers faster detection and visualization of latent fingermarks than existing methods. The proposed method is expected to increase detection efficiency for latent fingermarks and reduce time requirements and costs for forensic investigations.

Gene Variants Associated with Antisocial Behaviour: A Latent Variable Approach

Science.gov (United States)

Bentley, Mary Jane; Lin, Haiqun; Fernandez, Thomas V.; Lee, Maria; Yrigollen, Carolyn M.; Pakstis, Andrew J.; Katsovich, Liliya; Olds, David L.; Grigorenko, Elena L.; Leckman, James F.

2013-01-01

Objective: The aim of this study was to determine if a latent variable approach might be useful in identifying shared variance across genetic risk alleles that is associated with antisocial behaviour at age 15 years. Methods: Using a conventional latent variable approach, we derived an antisocial phenotype in 328 adolescents utilizing data from a…

Interferon-gamma release assay for the diagnosis of latent tuberculosis infection: A latent-class analysis.

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Tan N Doan

Full Text Available Accurate diagnosis and subsequent treatment of latent tuberculosis infection (LTBI is essential for TB elimination. However, the absence of a gold standard test for diagnosing LTBI makes assessment of the true prevalence of LTBI and the accuracy of diagnostic tests challenging. Bayesian latent class models can be used to make inferences about disease prevalence and the sensitivity and specificity of diagnostic tests using data on the concordance between tests. We performed the largest meta-analysis to date aiming to evaluate the performance of tuberculin skin test (TST and interferon-gamma release assays (IGRAs for LTBI diagnosis in various patient populations using Bayesian latent class modelling.Systematic search of PubMeb, Embase and African Index Medicus was conducted without date and language restrictions on September 11, 2017 to identify studies that compared the performance of TST and IGRAs for LTBI diagnosis. Two IGRA methods were considered: QuantiFERON-TB Gold In Tube (QFT-GIT and T-SPOT.TB. Studies were included if they reported 2x2 agreement data between TST and QFT-GIT or T-SPOT.TB. A Bayesian latent class model was developed to estimate the sensitivity and specificity of TST and IGRAs in various populations, including immune-competent adults, immune-compromised adults and children. A TST cut-off value of 10 mm was used for immune-competent subjects and 5 mm for immune-compromised individuals.A total of 157 studies were included in the analysis. In immune-competent adults, the sensitivity of TST and QFT-GIT were estimated to be 84% (95% credible interval [CrI] 82-85% and 52% (50-53%, respectively. The specificity of QFT-GIT was 97% (96-97% in non-BCG-vaccinated and 93% (92-94% in BCG-vaccinated immune-competent adults. The estimated figures for TST were 100% (99-100% and 79% (76-82%, respectively. T-SPOT.TB has comparable specificity (97% for both tests and better sensitivity (68% versus 52% than QFT-GIT in immune-competent adults

Embryonal Fyn-associated substrate (EFS) and CASS4: The lesser-known CAS protein family members.

Science.gov (United States)

Deneka, Alexander; Korobeynikov, Vladislav; Golemis, Erica A

2015-10-01

The CAS (Crk-associated substrate) adaptor protein family consists of four members: CASS1/BCAR1/p130Cas, CASS2/NEDD9/HEF1/Cas-L, CASS3/EFS/Sin and CASS4/HEPL. While CAS proteins lack enzymatic activity, they contain specific recognition and binding sites for assembly of larger signaling complexes that are essential for cell proliferation, survival, migration, and other processes. All family members are intermediates in integrin-dependent signaling pathways mediated at focal adhesions, and associate with FAK and SRC family kinases to activate downstream effectors regulating the actin cytoskeleton. Most studies of CAS proteins to date have been focused on the first two members, BCAR1 and NEDD9, with altered expression of these proteins now appreciated as influencing disease development and prognosis for cancer and other serious pathological conditions. For these family members, additional mechanisms of action have been defined in receptor tyrosine kinase (RTK) signaling, estrogen receptor signaling or cell cycle progression, involving discrete partner proteins such as SHC, NSP proteins, or AURKA. By contrast, EFS and CASS4 have been less studied, although structure-function analyses indicate they conserve many elements with the better-known family members. Intriguingly, a number of recent studies have implicated these proteins in immune system function, and the pathogenesis of developmental disorders, autoimmune disorders including Crohn's disease, Alzheimer's disease, cancer and other diseases. In this review, we summarize the current understanding of EFS and CASS4 protein function in the context of the larger CAS family group. Copyright © 2015 Elsevier B.V. All rights reserved.

Latent Toxoplasma gondii infection leads to improved action control.

Science.gov (United States)

Stock, Ann-Kathrin; Heintschel von Heinegg, Evelyn; Köhling, Hedda-Luise; Beste, Christian

2014-03-01

The parasite Toxoplasma gondii has been found to manipulate the behavior of its secondary hosts to increase its own dissemination which is commonly believed to be to the detriment of the host (manipulation hypothesis). The manipulation correlates with an up-regulation of dopaminergic neurotransmission. In humans, different pathologies have been associated with T. gondii infections but most latently infected humans do not seem to display overt impairments. Since a dopamine plus does not necessarily bear exclusively negative consequences in humans, we investigated potential positive consequences of latent toxoplasmosis (and the presumed boosting of dopaminergic neurotransmission) on human cognition and behavior. For this purpose, we focused on action cascading which has been shown to be modulated by dopamine. Based on behavioral and neurophysiological (EEG) data obtained by means of a stop-change paradigm, we were able to demonstrate that healthy young humans can actually benefit from latent T. gondii infection as regards their performance in this task (as indicated by faster response times and a smaller P3 component). The data shows that a latent infection which is assumed to affect the dopaminergic system can lead to paradoxical improvements of cognitive control processes in humans. Copyright © 2013 Elsevier Inc. All rights reserved.

Chromatin Structure of Epstein-Barr Virus Latent Episomes.

Science.gov (United States)

Lieberman, Paul M

2015-01-01

EBV latent infection is characterized by a highly restricted pattern of viral gene expression. EBV can establish latent infections in multiple different tissue types with remarkable variation and plasticity in viral transcription and replication. During latency, the viral genome persists as a multi-copy episome, a non-integrated-closed circular DNA with nucleosome structure similar to cellular chromosomes. Chromatin assembly and histone modifications contribute to the regulation of viral gene expression, DNA replication, and episome persistence during latency. This review focuses on how EBV latency is regulated by chromatin and its associated processes.

Viability, biofilm formation, and MazEF expression in drug-sensitive and drug-resistant Mycobacterium tuberculosis strains circulating in Xinjiang, China.

Science.gov (United States)

Zhao, Ji-Li; Liu, Wei; Xie, Wan-Ying; Cao, Xu-Dong; Yuan, Li

2018-01-01

Tuberculosis (TB) caused by Mycobacterium tuberculosis (MTB) is one of the most common chronic infectious amphixenotic diseases worldwide. Prevention and control of TB are greatly difficult, due to the increase in drug-resistant TB, particularly multidrug-resistant TB. We speculated that there were some differences between drug-sensitive and drug-resistant MTB strains and that mazEF 3,6,9 toxin-antitoxin systems (TASs) were involved in MTB viability. This study aimed to investigate differences in viability, biofilm formation, and MazEF expression between drug-sensitive and drug-resistant MTB strains circulating in Xinjiang, China, and whether mazEF 3,6,9 TASs contribute to MTB viability under stress conditions. Growth profiles and biofilm-formation abilities of drug-sensitive, drug-resistant MTB strains and the control strain H37Rv were monitored. Using molecular biology experiments, the mRNA expression of the mazF 3, 6, and 9 toxin genes, the mazE 3, 6, and 9 antitoxin genes, and expression of the MazF9 protein were detected in the different MTB strains, H37RvΔ mazEF 3,6,9 mutants from the H37Rv parent strain were generated, and mutant viability was tested. Ex vivo culture analyses demonstrated that drug-resistant MTB strains exhibit higher survival rates than drug-sensitive strains and the control strain H37Rv. However, there was no statistical difference in biofilm-formation ability in the drug-sensitive, drug-resistant, and H37Rv strains. mazE 3,6 mRNA-expression levels were relatively reduced in the drug-sensitive and drug-resistant strains compared to H37Rv. Conversely, mazE 3,9 expression was increased in drug-sensitive strains compared to drug-resistant strains. Furthermore, compared with the H37Rv strain, mazF 3,6 expression was increased in drug-resistant strains, mazF 9 expression was increased in drug-sensitive strains, and mazF 9 exhibited reduced expression in drug-resistant strains compared with drug-sensitive strains. Protein expression of mazF9

Using latent effects to determine the ecological importance of dissolved organic matter to marine invertebrates.

Science.gov (United States)

Wendt, Dean E; Johnson, Collin H

2006-10-01

The uptake and utilization of dissolved organic matter (DOM) by marine invertebrates is a field that has received significant attention over the past 100 years. Although it is well established that DOM is taken up by marine invertebrates, the extent to which it contributes to an animal's survival, growth, and reproduction (that is, the ecological benefits) remains largely unknown. Previous work seeking to demonstrate the putative ecological benefits of DOM uptake have examined them within a single life stage of an animal. Moreover, most of the benefits are demonstrated through indirect approaches by examining (1) mass balance, or (2) making comparisons of oxyenthalpic conversions of transport rates to metabolic rate as judged by oxygen consumption. We suggest that directly examining delayed metamorphosis or the latent effects associated with nutritional stress of larvae is a better model for investigating the ecological importance of DOM to marine invertebrates. We also provide direct evidence that availability of DOM enhances survival and growth of the bryozoan Bugula neritina. That DOM offsets latent effects in B. neritina suggests that the underlying mechanisms are at least in part energetic.

Probabilistic Latent Semantic Analyses (PLSA in Bibliometric Analysis for Technology Forecasting

Directory of Open Access Journals (Sweden)

Wang Zan

2007-03-01

Full Text Available Due to the availability of internet-based abstract services and patent databases, bibliometric analysis has become one of key technology forecasting approaches. Recently, latent semantic analysis (LSA has been applied to improve the accuracy in document clustering. In this paper, a new LSA method, probabilistic latent semantic analysis (PLSA which uses probabilistic methods and algebra to search latent space in the corpus is further applied in document clustering. The results show that PLSA is more accurate than LSA and the improved iteration method proposed by authors can simplify the computing process and improve the computing efficiency

Latent class models in financial data analysis

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Attilio Gardini

2007-10-01

Full Text Available This paper deals with optimal international portfolio choice by developing a latent class approach based on the distinction between international and non-international investors. On the basis of micro data, we analyze the effects of many social, demographic, economic and financial characteristics on the probability to be an international investor. Traditional measures of equity home bias do not allow for the existence of international investment rationing operators. On the contrary, by resorting to latent class analysis it is possible to detect the unobservable distinction between international investors and investors who are precluded from operating into international financial markets and, therefore, to evaluate the role of these unobservable constraints on equity home bias.

Incorporating Measurement Non-Equivalence in a Cross-Study Latent Growth Curve Analysis.

Science.gov (United States)

Flora, David B; Curran, Patrick J; Hussong, Andrea M; Edwards, Michael C

2008-10-01

A large literature emphasizes the importance of testing for measurement equivalence in scales that may be used as observed variables in structural equation modeling applications. When the same construct is measured across more than one developmental period, as in a longitudinal study, it can be especially critical to establish measurement equivalence, or invariance, across the developmental periods. Similarly, when data from more than one study are combined into a single analysis, it is again important to assess measurement equivalence across the data sources. Yet, how to incorporate non-equivalence when it is discovered is not well described for applied researchers. Here, we present an item response theory approach that can be used to create scale scores from measures while explicitly accounting for non-equivalence. We demonstrate these methods in the context of a latent curve analysis in which data from two separate studies are combined to create a single longitudinal model spanning several developmental periods.

The Integration of Continuous and Discrete Latent Variable Models: Potential Problems and Promising Opportunities

Science.gov (United States)

Bauer, Daniel J.; Curran, Patrick J.

2004-01-01

Structural equation mixture modeling (SEMM) integrates continuous and discrete latent variable models. Drawing on prior research on the relationships between continuous and discrete latent variable models, the authors identify 3 conditions that may lead to the estimation of spurious latent classes in SEMM: misspecification of the structural model,…

Characterization of a Latent Virus-Like Infection of Symbiotic Zooxanthellae▿

Science.gov (United States)

Lohr, Jayme; Munn, Colin B.; Wilson, William H.

2007-01-01

A latent virus-like agent, which we designated zooxanthella filamentous virus 1 (ZFV1), was isolated from Symbiodinium sp. strain CCMP 2465 and characterized. Transmission electron microscopy and analytical flow cytometry revealed the presence of a new group of distinctive filamentous virus-like particles after exposure of the zooxanthellae to UV light. Examination of thin sections of the zooxanthellae revealed the formation and proliferation of filamentous virus-like particles in the UV-induced cells. Assessment of Symbiodinium sp. cultures was used here as a model to show the effects of UV irradiance and induction of potential latent viruses. The unique host-virus system described here provides insight into the role of latent infections in zooxanthellae through environmentally regulated viral induction mechanisms. PMID:17351090

Characterization of a latent virus-like infection of symbiotic zooxanthellae.

Science.gov (United States)

Lohr, Jayme; Munn, Colin B; Wilson, William H

2007-05-01

A latent virus-like agent, which we designated zooxanthella filamentous virus 1 (ZFV1), was isolated from Symbiodinium sp. strain CCMP 2465 and characterized. Transmission electron microscopy and analytical flow cytometry revealed the presence of a new group of distinctive filamentous virus-like particles after exposure of the zooxanthellae to UV light. Examination of thin sections of the zooxanthellae revealed the formation and proliferation of filamentous virus-like particles in the UV-induced cells. Assessment of Symbiodinium sp. cultures was used here as a model to show the effects of UV irradiance and induction of potential latent viruses. The unique host-virus system described here provides insight into the role of latent infections in zooxanthellae through environmentally regulated viral induction mechanisms.

The latent effect of inertia in the modal choice

DEFF Research Database (Denmark)

Cherchi, Elisabetta; Meloni, Italo; Ortúzar, Juan de Dios

2014-01-01

The existence of habit (leading to inertia) in the choice process has been approached in the literature in a number of ways. In transport, inertia has been studied mainly using “long panel” data, or mixed revealed and stated preference data. In these studies inertia links the choice made in two...... approaches. We assume that inertia is revealed by past behaviour and affects also the initial condition, but we recognise that past behaviour is only an indicator of habitual behaviour, the true process behind the formation of habitual behaviour being latent. We estimate a hybrid choice model using a set...... of revealed and stated mode choice preferences collected in Cagliari (Italy). We found a significant latent inertia in the revealed preference data, indicating that inertia affects the initial conditions. The latent inertia is revealed by the frequency of past behaviour but the effect of trip frequency...

Using standard serology blood tests to diagnose latent syphilis

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G. L. Katunin

2016-01-01

Full Text Available Goal. To conduct a comparative assessment of the results of regulated serological tests obtained as a result of blood tests in patients suffering from latent syphilis. Materials and methods. The authors examined 187 patient medical records with newly diagnosed latent syphilis in FGBU GNTsDK (State Research Center for Dermatology, Venereology and Cosmetology, Health Ministry of the Russian Federation, in 2006-2015. The results of patient blood tests were analyzed with the use of non-treponemal (microprecipitation test/RPR and treponemal (passive hemagglutination test, immune-enzyme assay (IgA, IgM, IgG, IFabs, immunofluorescence test and Treponema pallidum immobilization test serology tests. Results. According to the results of blood tests of latent syphilis patients, the largest number of positive results was obtained as a result of treponemal serology tests such as immune-enzyme assay (100%, passive hemagglutination test (100% and IFabs (100%. The greatest number of negative results was observed in non-treponemal (microprecipitation test/RPR serology tests: in 136 (72.7% patients; evidently positive results (4+ test results were obtained in 8 (4.3% patients only. According to the results of a comparative analysis of blood tests in patients suffering from latent syphilis obtained with the use of treponemal serology tests, the greatest number of evidently positive results (4+ was noted for the passive hemagglutination test (67.9%. Negative treponemal test results were obtained with the use of the immunofluorescence test and Treponema pallidum immobilization test (21.9% and 11.8% of cases, respectively. Moreover, weakly positive results prevailed for the immunofluorescence test: in 65 (34.7% patients. Conclusion. These data confirm that the following treponemal tests belong to the most reliable ones for revealing patients suffering from latent syphilis: immune-enzyme assay, passive hemagglutination test and IFabs.

Modeling Psychological Attributes in Psychology – An Epistemological Discussion: Network Analysis vs. Latent Variables

Science.gov (United States)

Guyon, Hervé; Falissard, Bruno; Kop, Jean-Luc

2017-01-01

Network Analysis is considered as a new method that challenges Latent Variable models in inferring psychological attributes. With Network Analysis, psychological attributes are derived from a complex system of components without the need to call on any latent variables. But the ontological status of psychological attributes is not adequately defined with Network Analysis, because a psychological attribute is both a complex system and a property emerging from this complex system. The aim of this article is to reappraise the legitimacy of latent variable models by engaging in an ontological and epistemological discussion on psychological attributes. Psychological attributes relate to the mental equilibrium of individuals embedded in their social interactions, as robust attractors within complex dynamic processes with emergent properties, distinct from physical entities located in precise areas of the brain. Latent variables thus possess legitimacy, because the emergent properties can be conceptualized and analyzed on the sole basis of their manifestations, without exploring the upstream complex system. However, in opposition with the usual Latent Variable models, this article is in favor of the integration of a dynamic system of manifestations. Latent Variables models and Network Analysis thus appear as complementary approaches. New approaches combining Latent Network Models and Network Residuals are certainly a promising new way to infer psychological attributes, placing psychological attributes in an inter-subjective dynamic approach. Pragmatism-realism appears as the epistemological framework required if we are to use latent variables as representations of psychological attributes. PMID:28572780

PTSD's latent structure in Malaysian tsunami victims: assessing the newly proposed Dysphoric Arousal model.

Science.gov (United States)

Armour, Cherie; Raudzah Ghazali, Siti; Elklit, Ask

2013-03-30

The underlying latent structure of Posttraumatic Stress Disorder (PTSD) is widely researched. However, despite a plethora of factor analytic studies, no single model has consistently been shown as superior to alternative models. The two most often supported models are the Emotional Numbing and the Dysphoria models. However, a recently proposed five-factor Dysphoric Arousal model has been gathering support over and above existing models. Data for the current study were gathered from Malaysian Tsunami survivors (N=250). Three competing models (Emotional Numbing/Dysphoria/Dysphoric Arousal) were specified and estimated using Confirmatory Factor Analysis (CFA). The Dysphoria model provided superior fit to the data compared to the Emotional Numbing model. However, using chi-square difference tests, the Dysphoric Arousal model showed a superior fit compared to both the Emotional Numbing and Dysphoria models. In conclusion, the current results suggest that the Dysphoric Arousal model better represents PTSD's latent structure and that items measuring sleeping difficulties, irritability/anger and concentration difficulties form a separate, unique PTSD factor. These results are discussed in relation to the role of Hyperarousal in PTSD's on-going symptom maintenance and in relation to the DSM-5. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Endogenous Opioid-Masked Latent Pain Sensitization

DEFF Research Database (Denmark)

Pereira, Manuel P; Donahue, Renee R; Dahl, Jørgen B

2015-01-01

UNLABELLED: Following the resolution of a severe inflammatory injury in rodents, administration of mu-opioid receptor inverse agonists leads to reinstatement of pain hypersensitivity. The mechanisms underlying this form of latent pain sensitization (LS) likely contribute to the development of chr...

Perbandingan Hasil Deteksi Plagiarisme Dokumen dengan Metode Jaro-Winkler Distance dan Metode Latent Semantic Analysis

Directory of Open Access Journals (Sweden)

Tinaliah Tinaliah

2018-01-01

Full Text Available Various methods are applied in the application of plagiarism detection to help check the similarity of a document. Jaro-Winkler Distance can measure the distance between two strings. However, this method basically depends on the position of the word. Latent Semantic Analysis emphasizes the words contained in the document regardless of its linguistic character. This study compares the results of plagiarism detection using the Jaro-Winkler Distance and the Latent Semantic Analysis method. From comparing results of  Jaro-Winkler Distance method and Latent Semantic Analysis method, Jaro-Winkler Distance method is better than Latent Semantic Analysis method if using the same test data. Jaro-Winkler Distance method will give plagiarism result 100% and Latent Semantic Analysis method will give plagiarism result 97,14%. Beragam metode diterapkan dalam aplikasi deteksi plagiarisme untuk membantu mengecek tingkat kesamaan sebuah dokumen. Metode Jaro-Winkler Distance dapat mengukur kesamaan antara dua buah string dan sangat bergantung pada urutan atau posisi kata. Latent Semantic Analysis mementingkan kata-kata yang terkandung di dalam dokumen tanpa memperhatikan karakter linguistiknya. Penelitian ini melakukan perbandingan hasil deteksi plagiarisme dengan menggunakan metode Jaro-Winkler Distance dan metode Latent Semantic Analysis. Hasil pendeteksian plagiarisme dokumen menggunakan metode Jaro-Winkler Distance memberikan hasil yang lebih baik daripada metode Latent Semantic Analysis, yaitu jika data yang dibandingkan sama persis maka akan menghasilkan nilai plagiat sebesar 100%, sedangkan metode Latent Semantic Analysis menghasilkan nilai plagiat sebesar 97,14%.

Latent cluster analysis of ALS phenotypes identifies prognostically differing groups.

Directory of Open Access Journals (Sweden)

Jeban Ganesalingam

2009-09-01

Full Text Available Amyotrophic lateral sclerosis (ALS is a degenerative disease predominantly affecting motor neurons and manifesting as several different phenotypes. Whether these phenotypes correspond to different underlying disease processes is unknown. We used latent cluster analysis to identify groupings of clinical variables in an objective and unbiased way to improve phenotyping for clinical and research purposes.Latent class cluster analysis was applied to a large database consisting of 1467 records of people with ALS, using discrete variables which can be readily determined at the first clinic appointment. The model was tested for clinical relevance by survival analysis of the phenotypic groupings using the Kaplan-Meier method.The best model generated five distinct phenotypic classes that strongly predicted survival (p<0.0001. Eight variables were used for the latent class analysis, but a good estimate of the classification could be obtained using just two variables: site of first symptoms (bulbar or limb and time from symptom onset to diagnosis (p<0.00001.The five phenotypic classes identified using latent cluster analysis can predict prognosis. They could be used to stratify patients recruited into clinical trials and generating more homogeneous disease groups for genetic, proteomic and risk factor research.

Identification of novel mazEF/pemIK family toxin-antitoxin loci and their distribution in the Staphylococcus genus.

Science.gov (United States)

Bukowski, Michal; Hyz, Karolina; Janczak, Monika; Hydzik, Marcin; Dubin, Grzegorz; Wladyka, Benedykt

2017-10-18

The versatile roles of toxin-antitoxin (TA) systems in bacterial physiology and pathogenesis have been investigated for more than three decades. Diverse TA loci in Bacteria and Archaea have been identified in genome-wide studies. The advent of massive parallel sequencing has substantially expanded the number of known bacterial genomic sequences over the last 5 years. In staphylococci, this has translated into an impressive increase from a few tens to a several thousands of available genomes, which has allowed us for the re-evalution of prior conclusions. In this study, we analysed the distribution of mazEF/pemIK family TA system operons in available staphylococcal genomes and their prevalence in mobile genetic elements. 10 novel m azEF/pemIK homologues were identified, each with a corresponding toxin that plays a potentially different and undetermined physiological role. A detailed characterisation of these TA systems would be exceptionally useful. Of particular interest are those associated with an SCCmec mobile genetic element (responsible for multidrug resistance transmission) or representing the joint horizontal transfer of TA systems and determinants of vancomycin resistance from enterococci. The involvement of TA systems in maintaining mobile genetic elements and the associations between novel mazEF/pemIK loci and those which carry drug resistance genes highlight their potential medical importance.

Skeletal muscle eEF2 and 4EBP1 phosphorylation during endurance exercise is dependent on intensity and muscle fiber type

DEFF Research Database (Denmark)

Rose, Adam John; Bisiani, Bruno; Vistisen, Bodil

2009-01-01

that the increase in skeletal muscle eEF2 Thr(56) phosphorylation was restricted to type I myofibers. Taken together, these data suggest that the depression of skeletal muscle protein synthesis with endurance-type exercise may be regulated at both initiation (i.e. 4EBP1) and elongation (i.e. eEF2) steps, with eEF2......Protein synthesis in skeletal muscle is known to decrease during exercise and it has been suggested that this may depend on the magnitude of the relative metabolic stress within the contracting muscle. To examine the mechanisms behind this, the effect of exercise intensity on skeletal muscle......) increased during exercise but was not influenced by exercise intensity, and was lower than rest 30min after exercise. On the other hand, 4EBP1 phosphorylation at Thr(37/46) decreased during exercise and this decrease was greater at higher exercise intensities, and was similar to rest 30min after exercise...

Visualizing Confidence Bands for Semiparametrically Estimated Nonlinear Relations among Latent Variables

Science.gov (United States)

Pek, Jolynn; Chalmers, R. Philip; Kok, Bethany E.; Losardo, Diane

2015-01-01

Structural equation mixture models (SEMMs), when applied as a semiparametric model (SPM), can adequately recover potentially nonlinear latent relationships without their specification. This SPM is useful for exploratory analysis when the form of the latent regression is unknown. The purpose of this article is to help users familiar with structural…

Defining a Family of Cognitive Diagnosis Models Using Log-Linear Models with Latent Variables

Science.gov (United States)

Henson, Robert A.; Templin, Jonathan L.; Willse, John T.

2009-01-01

This paper uses log-linear models with latent variables (Hagenaars, in "Loglinear Models with Latent Variables," 1993) to define a family of cognitive diagnosis models. In doing so, the relationship between many common models is explicitly defined and discussed. In addition, because the log-linear model with latent variables is a general model for…

Single-Trial Inference on Visual Attention

DEFF Research Database (Denmark)

Dyrholm, Mads; Kyllingsbæk, Søren; Vangkilde, Signe Allerup

2011-01-01

In this paper we take a step towards single-trial behavioral modeling within a Theory of Visual Attention (TVA). In selective attention tasks, such as the Partial Report paradigm, the subject is asked to ignore distractors and only report stimuli that belong to the target class. Nothing about...... Report trial. This result retrodicts a latent attentional state of the subject using the observed response from that particular trial and thus differs from other predictions made with TVA which are based on expected values of observed variables. We show an example of the result in single-trial analysis...

Effect of Latent Heat Released by Freezing Droplets during Frost Wave Propagation.

Science.gov (United States)

Chavan, Shreyas; Park, Deokgeun; Singla, Nitish; Sokalski, Peter; Boyina, Kalyan; Miljkovic, Nenad

2018-05-21

Frost spreads on nonwetting surfaces during condensation frosting via an interdroplet frost wave. When a supercooled condensate water droplet freezes on a hydrophobic or superhydrophobic surface, neighboring droplets still in the liquid phase begin to evaporate. Two possible mechanisms govern the evaporation of neighboring water droplets: (1) The difference in saturation pressure of the water vapor surrounding the liquid and frozen droplets induces a vapor pressure gradient, and (2) the latent heat released by freezing droplets locally heats the substrate, leading to evaporation of nearby droplets. The relative significance of these two mechanisms is still not understood. Here, we study the significance of the latent heat released into the substrate by freezing droplets, and its effect on adjacent droplet evaporation, by studying the dynamics of individual water droplet freezing on aluminum-, copper-, and glass-based hydrophobic and superhydrophobic surfaces. The latent heat flux released into the substrate was calculated from the measured droplet sizes and the respective freezing times ( t f ), defined as the time from initial ice nucleation within the droplet to complete droplet freezing. To probe the effect of latent heat release, we performed three-dimensional transient finite element simulations showing that the transfer of latent heat to neighboring droplets is insignificant and accounts for a negligible fraction of evaporation during microscale frost wave propagation. Furthermore, we studied the effect of substrate thermal conductivity on the transfer of latent heat transfer to neighboring droplets by investigating the velocity of ice bridge formation. The velocity of the ice bridge was independent of the substrate thermal conductivity, indicating that adjacent droplet evaporation during condensation frosting is governed solely by vapor pressure gradients. This study not only provides key insights into the individual droplet freezing process but also

CARRYING OF FRENCH VISAS FOR HOLDERS OF CATEGORY 'EF' FRENCH ATTESTATIONS DE FONCTIONS

CERN Multimedia

Service des Relations avec les Pays Hôtes

1999-01-01

The French Ministry of Foreign Affairs has informed the Organisation that members of the personnel resident in Switzerland and holding Category 'EF' French Attestations de functions are not obliged to be in possession of French visas. When temporarily travelling through France on OFFICIAL CERN BUSINESS, provided they are carrying the valid Attestation and a valid national passport with them.Relations with the Host States Servicehttp://www.cern.ch/relations/Tel. 72848

New developing reagent for latent fingermark visualization: Fuller’s earth (Multani Mitti

Directory of Open Access Journals (Sweden)

Pallavi Thakur

2016-12-01

Full Text Available A number of methods have been reported in the literature for the development of latent fingermarks on different surfaces. This paper reports a new and simple powdering method which is non-toxic and has been employed on different substrates successfully for the development and visualization of latent fingermarks up to the time period of 6 days in varying temperature conditions. In this investigation a less expensive, simple and easily available fuller’s earth (Multani Mitti powder has been used to decipher the latent fingermarks on different substrates namely black cardboard box, clear glass, coverslip box, steel surface, laminated wooden sheet, clear plastic, colored plastic bag and surface of highlighter pen. It is observed that it gives very clear results on majority of substrates and can be successfully used for the development and visualization of latent fingermarks.

The latent rationality of risky decisions

Energy Technology Data Exchange (ETDEWEB)

Japp, K.P. [Bielefeld Univ. (Germany). Faculty for Sociology

1999-12-01

The general question of rationality has changed from the old-fashioned difference of means and ends to the modern difference of system and environment. Organizations as social systems producing and reproducing decisions translate this difference into the difference of stability and variety. The question then is: In which way can the difference between stability and variety express rationality? - In the temporal dimension of risk-taking, re-entries may be expressed as 'present futures' or 'future presences'. These expressions indicate both: The irresolvable uncertainty of any risk-taking, indicated by open futures, and its boundedness by self-application of distinctions, e.g. projected futures from the background of a known past. - In the material dimension of risk-taking, re-entries may be expressed as 'stable flexibility' or 'flexible stability'. Again, these expressions indicate both: The irresolvable uncertainty of any risk-taking, indicted by open flexibilities, and its boundedness by self-application of distinctions, e.g. flexibility and stability after learning the respective costs of the single options. In the social dimension of risk-taking, re-entries may be expressed as 'pragmatic dissent' or 'controversial pragmatism'. Again, these expressions indicate both: The irresolvable uncertainty of any risk-taking, indicated by open dissent or controversies, and its boundedness by self-application of distinctions, e.g. pragmatic agreements and irresolvable dissent. Again, all three asymmetries represent re-entries. The built-in preferences simply do not work without the subtleties of re-entries, at least when these processes are described by sociologically informed observers. Who else should know that he or she is operating on the basis of something called re-entries? In everyday life communication, no one sees a thing like that since every observation has an in-built bias for one side of a distinction

The latent rationality of risky decisions

International Nuclear Information System (INIS)

Japp, K.P.

1999-01-01

The general question of rationality has changed from the old-fashioned difference of means and ends to the modern difference of system and environment. Organizations as social systems producing and reproducing decisions translate this difference into the difference of stability and variety. The question then is: In which way can the difference between stability and variety express rationality? - In the temporal dimension of risk-taking, re-entries may be expressed as 'present futures' or 'future presences'. These expressions indicate both: The irresolvable uncertainty of any risk-taking, indicated by open futures, and its boundedness by self-application of distinctions, e.g. projected futures from the background of a known past. - In the material dimension of risk-taking, re-entries may be expressed as 'stable flexibility' or 'flexible stability'. Again, these expressions indicate both: The irresolvable uncertainty of any risk-taking, indicted by open flexibilities, and its boundedness by self-application of distinctions, e.g. flexibility and stability after learning the respective costs of the single options. In the social dimension of risk-taking, re-entries may be expressed as 'pragmatic dissent' or 'controversial pragmatism'. Again, these expressions indicate both: The irresolvable uncertainty of any risk-taking, indicated by open dissent or controversies, and its boundedness by self-application of distinctions, e.g. pragmatic agreements and irresolvable dissent. Again, all three asymmetries represent re-entries. The built-in preferences simply do not work without the subtleties of re-entries, at least when these processes are described by sociologically informed observers. Who else should know that he or she is operating on the basis of something called re-entries? In everyday life communication, no one sees a thing like that since every observation has an in-built bias for one side of a distinction. So rationality will stay latent as the operation of re

Shallow and Deep Latent Heating Modes Over Tropical Oceans Observed with TRMM PR Spectral Latent Heating Data

Science.gov (United States)

Takayabu, Yukari N.; Shige, Shoichi; Tao, Wei-Kuo; Hirota, Nagio

2010-01-01

The global hydrological cycle is central to the Earth's climate system, with rainfall and the physics of its formation acting as the key links in the cycle. Two-thirds of global rainfall occurs in the Tropics. Associated with this rainfall is a vast amount of heat, which is known as latent heat. It arises mainly due to the phase change of water vapor condensing into liquid droplets; three-fourths of the total heat energy available to the Earth's atmosphere comes from tropical rainfall. In addition, fresh water provided by tropical rainfall and its variability exerts a large impact upon the structure and motions of the upper ocean layer. Three-dimensional distributions of latent heating estimated from Tropical Rainfall Measuring Mission Precipitation Radar (TRMM PR)utilizing the Spectral Latent Heating (SLH) algorithm are analyzed. Mass-weighted and vertically integrated latent heating averaged over the tropical oceans is estimated as approx.72.6 J/s (approx.2.51 mm/day), and that over tropical land is approx.73.7 J/s (approx.2.55 mm/day), for 30degN-30degS. It is shown that non-drizzle precipitation over tropical and subtropical oceans consists of two dominant modes of rainfall systems, deep systems and congestus. A rough estimate of shallow mode contribution against the total heating is about 46.7 % for the average tropical oceans, which is substantially larger than 23.7 % over tropical land. While cumulus congestus heating linearly correlates with the SST, deep mode is dynamically bounded by large-scale subsidence. It is notable that substantial amount of rain, as large as 2.38 mm day-1 in average, is brought from congestus clouds under the large-scale subsiding circulation. It is also notable that even in the region with SST warmer than 28 oC, large-scale subsidence effectively suppresses the deep convection, remaining the heating by congestus clouds. Our results support that the entrainment of mid-to-lower-tropospheric dry air, which accompanies the large

Factors affecting accuracy of ventricular volume and ejection fraction measured by gated Tl-201 myocardial perfusion single photon emission computed tomography

International Nuclear Information System (INIS)

Pai, Moon Sun; Yang, You Jung; Im, Ki Chun; Hong, Il Ki; Yun, Sung Cheol; Kang, Duk Hyun; Song, Jae Kwan; Moon, Dae Hyuk

2005-01-01

Systemic errors in the gated single photon emission computed tomography (SPECT) measurement of left ventricular (LV) end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) may occur. We evaluated whether patient-related factors affected the accuracy of EDV, ESV, and EF measured by electrocardiogram-gated Tl-201 SPECT. A total of 518 patients without perfusion defects on Tl-201 SPECT or coronary artery disease were studied. EDV, ESV, and EF were measured from echocardiography and adenosine stress/redistribution gated Tl-201 SPECT using commercially available software packages (QGS and 4D-MSPECT). We identified factors affecting the accuracy of gated SPECT via multiple linear regression analysis of the differences between echocardiography and gated SPECT. Gated SPECT analyzed with QGS underestimated EDV and ESV, and overestimated EF, but 4D-MSPECT overestimated all those values (p<0.001). Independent variables that increased the difference in EDV between echocardiography and gated SPECT were decreasing LV end-diastolic wall thickness, decreasing body surface area, female sex and increasing EDV (p< 0.001). Those for ESV were decreasing LV end-systolic wall thickness, female sex, and decreasing ESV (p<0.001). Increasing end-systolic wall thickness, male sex and decreasing age were independent determinants associated with an increased difference in EF (p< 0.001). Adenosine stress SPECT showed significantly higher EDV and ESV values and a lower EF than did redistribution SPECT (p< 0.001). In determination of EF, QGS demonstrated a smaller bias than did 4D-MSPECT. However, in men with LV hypertrophy, 4D-MSPECT was superior to QGS. Systemic error by gated Tl-201 SPECT is determined by individual patient-characteristics

Loss of translation elongation factor (eEF1A2) expression in vivo differentiates between Wallerian degeneration and dying-back neuronal pathology.

Science.gov (United States)

Murray, Lyndsay M; Thomson, Derek; Conklin, Annalijn; Wishart, Thomas M; Gillingwater, Thomas H

2008-12-01

Wallerian degeneration and dying-back pathology are two well-known cellular pathways capable of regulating the breakdown and loss of axonal and synaptic compartments of neurons in vivo. However, the underlying mechanisms and molecular triggers of these pathways remain elusive. Here, we show that loss of translation elongation factor eEF1A2 expression in lower motor neurons and skeletal muscle fibres in homozygous Wasted mice triggered a dying-back neuropathy. Synaptic loss at the neuromuscular junction occurred in advance of axonal pathology and by a mechanism morphologically distinct from Wallerian degeneration. Dying-back pathology in Wasted mice was accompanied by reduced expression levels of the zinc finger protein ZPR1, as found in other dying-back neuropathies such as spinal muscular atrophy. Surprisingly, experimental nerve lesion revealed that Wallerian degeneration was significantly delayed in homozygous Wasted mice; morphological assessment revealed that approximately 80% of neuromuscular junctions in deep lumbrical muscles at 24 h and approximately 50% at 48 h had retained motor nerve terminals following tibial nerve lesion. This was in contrast to wild-type and heterozygous Wasted mice where < 5% of neuromuscular junctions had retained motor nerve terminals at 24 h post-lesion. These data show that eEF1A2 expression is required to prevent the initiation of dying-back pathology at the neuromuscular junction in vivo. In contrast, loss of eEF1A2 expression significantly inhibited the initiation and progression of Wallerian degeneration in vivo. We conclude that loss of eEF1A2 expression distinguishes mechanisms underlying dying-back pathology from those responsible for Wallerian degeneration in vivo and suggest that eEF1A2-dependent cascades may provide novel molecular targets to manipulate neurodegenerative pathways in lower motor neurons.

Multiplex real-time PCR for the detection and quantification of latent and persistent viral genomes in cellular or plasma blood fractions.

Science.gov (United States)

Compston, Lara Isobel; Sarkobie, Francis; Li, Chengyao; Candotti, Daniel; Opare-Sem, Ohene; Allain, Jean-Pierre

2008-07-01

In common with latent viruses such as herpesviruses, parvovirus B19, HBV and GBV-C are contained successfully by the immune response and persist in the host. When immune control breaks down, reactivation of both latent and persistent viruses occurs. Two multiplex assays were developed (B19, HBV, HHV-8), (EBV, CMV, VZV) for blood screening, and tested on blood donor samples from Ghana to determine baseline prevalence of viraemia in immunocompetent persons. Single-virus real-time quantitative PCR (qPCR) assays were optimised for viral load determination of positive initial screening. The qPCR method utilised was absolute quantification with external standards. Multiplex and single-virus qPCR assays had similar sensitivity, except for the B19 assay in which sensitivity was 100-fold lower. Assays were optimised for reproducibility and repeatability, with R(2) of 0.9 being obtained for most assays. With the exception of B19 and CMV, assays had 100% detection limit ranging between 10(1) and 10(2) copies, IU or arbitrary units under single-virus and multiplex assay conditions. The prevalence of viraemia was 1.6% HBV (0.8% DNA+/HBsAg-, 0.8% DNA+/HBsAg+), 0.8% parvovirus B19, and 3.3% GBV-C viraemia in the plasma fraction. The prevalence of four herpesviruses was 1.0% HHV-8, 0.85% CMV, and 8.3% EBV, and no detectable VZV viraemia.

A Cell Culture Model of Latent and Lytic Herpes Simplex Virus Type 1 Infection in Spiral Ganglion.

Science.gov (United States)

Liu, Yuehong; Li, Shufeng

2015-01-01

Reactivation of latent herpes simplex virus type 1 (HSV-1) in spiral ganglion neurons (SGNs) is supposed to be one of the causes of idiopathic sudden sensorineural hearing loss. This study aims to establish a cell culture model of latent and lytic HSV-1 infection in spiral ganglia. In the presence of acyclovir, primary cultures of SGNs were latently infected with HSV-1 expressing green fluorescent protein. Four days later, these cells were treated with trichostatin A (TSA), a known chemical reactivator of HSV-1. TCID50 was used to measure the titers of virus in cultures on Vero cells. RNA from cultures was detected for the presence of transcripts of ICP27 and latency-associated transcript (LAT) using reverse transcription polymerase chain reaction. There is no detectable infectious HSV-1 in latently infected cultures, whereas they could be observed in both lytically infected and latently infected/TSA-treated cultures. LAT was the only detectable transcript during latent infection, whereas lytic ICP27 transcript was detected in lytically infected and latently infected/TSA-treated cultures. Cultured SGNs can be both latently and lytically infected with HSV-1. Furthermore, latently infected SGNs can be reactivated using TSA, yielding infectious virus.

The Latent Class Model as a Measurement Model for Situational Judgment Tests

Directory of Open Access Journals (Sweden)

Frank Rijmen

2011-11-01

Full Text Available In a situational judgment test, it is often debatable what constitutes a correct answer to a situation. There is currently a multitude of scoring procedures. Establishing a measurement model can guide the selection of a scoring rule. It is argued that the latent class model is a good candidate for a measurement model. Two latent class models are applied to the Managing Emotions subtest of the Mayer, Salovey, Caruso Emotional Intelligence Test: a plain-vanilla latent class model, and a second-order latent class model that takes into account the clustering of several possible reactions within each hypothetical scenario of the situational judgment test. The results for both models indicated that there were three subgroups characterised by the degree to which differentiation occurred between possible reactions in terms of perceived effectiveness. Furthermore, the results for the second-order model indicated a moderate cluster effect.

eEF1A Controls ascospore differentiation through elevated accuracy, but controls longevity and fruiting body formation through another mechanism in Podospora anserina.

Science.gov (United States)

Silar, P; Lalucque, H; Haedens, V; Zickler, D; Picard, M

2001-01-01

Antisuppressor mutations in the eEF1A gene of Podospora anserina were previously shown to impair ascospore formation, to drastically increase life span, and to permit the development of the Crippled Growth degenerative process. Here, we show that eEF1A controls ascospore formation through accuracy level maintenance. Examination of antisuppressor mutant perithecia reveals two main cytological defects, mislocalization of spindle and nuclei and nuclear death. Antisuppression levels are shown to be highly dependent upon both the mutation site and the suppressor used, precluding any correlation between antisuppression efficiency and severity of the sporulation impairment. Nevertheless, severity of ascospore differentiation defect is correlated with resistance to paromomycin. We also show that eEF1A controls fruiting body formation and longevity through a mechanism(s) different from accuracy control. In vivo, GFP tagging of the protein in a way that partly retains its function confirmed earlier cytological observation; i.e., this factor is mainly diffuse within the cytosol, but may transiently accumulate within nuclei or in defined regions of the cytoplasm. These data emphasize the fact that the translation apparatus exerts a global regulatory control over cell physiology and that eEF1A is one of the key factors involved in this monitoring. PMID:11514440

Prevalence of latent Mycobacterium tuberculosis infection among professionals of the primary healthcare network

Directory of Open Access Journals (Sweden)

Tássia Silvana Borges

2014-06-01

Full Text Available Objective: To estimate the prevalence of latent M. tuberculosis infection and identify characteristics related to latent infection among workers of the primary healthcare network.Methods: Cross-sectional, observational and descriptive study, conducted in 2011, included 137 basic health workers who performed their activities in a municipality. Interviews were carried out addressing characteristics of exposure at work (BCG vaccination, length of time working in the health system, potential exposure to tuberculosis, HIV infection, use of corticosteroids, diabetes, use of tobacco or alcohol and subsequently performed tuberculin skin test (TST. Data was analyzed with Fischer and Student’s t-test (p < 0.05. Results: Health professionals were mostly women (n=126, 92% with mean age of 35.3 (± 9.1 years. Among the reactors, 25 (55.5% sought medical care, and of these, 7 (28% underwent prophylactic treatment. The prevalence of latent tuberculosis was 32.8%. Of the characteristics evaluated, only smoking (OR 3.03; 95%CI 1.05-8.77 was associated with latent infection. Conclusion: The estimated prevalence of latent M. tuberculosis infection among the evaluated health workers was 32.8%. As for the characteristics studied, it was not possible to relate them to latent infection among workers in primary healthcare network, with the exception of the smoking habit. doi: 10.5020/18061230.2014.p269

Evaluation of HIV Risk Reduction and Intervention Programs via Latent Growth Model.

Science.gov (United States)

Wang, Jichuan; Siegal, Harvey A.; Falck, Russel S.; Carlson, Robert G.; Rahman, Ahmmed

1999-01-01

Demonstrates how the latent growth model can be applied to the evaluation of programs targeting HIV risk behavior among drug users. Multigroup piecewise latent growth models were fit to longitudinal data with three repeated response measures. Participants were 430 drug users and their sex partners. (SLD)

A Composite Likelihood Inference in Latent Variable Models for Ordinal Longitudinal Responses

Science.gov (United States)

Vasdekis, Vassilis G. S.; Cagnone, Silvia; Moustaki, Irini

2012-01-01

The paper proposes a composite likelihood estimation approach that uses bivariate instead of multivariate marginal probabilities for ordinal longitudinal responses using a latent variable model. The model considers time-dependent latent variables and item-specific random effects to be accountable for the interdependencies of the multivariate…

Full Text or Abstract? : Examining Topic Coherence Scores Using Latent Dirichlet Allocation

NARCIS (Netherlands)

Syed, S.; Spruit, M.

2017-01-01

This paper assesses topic coherence and human topic ranking of uncovered latent topics from scientific publications when utilizing the topic model latent Dirichlet allocation (LDA) on abstract and full-text data. The coherence of a topic, used as a proxy for topic quality, is based on the

Microbeam mapping of single event latchups and single event upsets in CMOS SRAMs

International Nuclear Information System (INIS)

Barak, J.; Adler, E.; Fischer, B.E.; Schloegl, M.; Metzger, S.

1998-01-01

The first simultaneous microbeam mapping of single event upset (SEU) and latchup (SEL) in the CMOS RAM HM65162 is presented. The authors found that the shapes of the sensitive areas depend on V DD , on the ions being used and on the site on the chip being hit by the ion. In particular, they found SEL sensitive sites close to the main power supply lines between the memory-bit-arrays by detecting the accompanying current surge. All these SELs were also accompanied by bit-flips elsewhere in the memory (which they call indirect SEUs in contrast to the well known SEUs induced in the hit memory cell only). When identical SEL sensitive sites were hit farther away from the supply lines only indirect SEL sensitive sites could be detected. They interpret these events as latent latchups in contrast to the classical ones detected by their induced current surge. These latent SELs were probably decoupled from the main supply lines by the high resistivity of the local supply lines

Structural identifiability of cyclic graphical models of biological networks with latent variables.

Science.gov (United States)

Wang, Yulin; Lu, Na; Miao, Hongyu

2016-06-13

Graphical models have long been used to describe biological networks for a variety of important tasks such as the determination of key biological parameters, and the structure of graphical model ultimately determines whether such unknown parameters can be unambiguously obtained from experimental observations (i.e., the identifiability problem). Limited by resources or technical capacities, complex biological networks are usually partially observed in experiment, which thus introduces latent variables into the corresponding graphical models. A number of previous studies have tackled the parameter identifiability problem for graphical models such as linear structural equation models (SEMs) with or without latent variables. However, the limited resolution and efficiency of existing approaches necessarily calls for further development of novel structural identifiability analysis algorithms. An efficient structural identifiability analysis algorithm is developed in this study for a broad range of network structures. The proposed method adopts the Wright's path coefficient method to generate identifiability equations in forms of symbolic polynomials, and then converts these symbolic equations to binary matrices (called identifiability matrix). Several matrix operations are introduced for identifiability matrix reduction with system equivalency maintained. Based on the reduced identifiability matrices, the structural identifiability of each parameter is determined. A number of benchmark models are used to verify the validity of the proposed approach. Finally, the network module for influenza A virus replication is employed as a real example to illustrate the application of the proposed approach in practice. The proposed approach can deal with cyclic networks with latent variables. The key advantage is that it intentionally avoids symbolic computation and is thus highly efficient. Also, this method is capable of determining the identifiability of each single parameter and

The Latent Structure of Attention Deficit/Hyperactivity Disorder in an Adult Sample

Science.gov (United States)

Marcus, David K.; Norris, Alyssa L.; Coccaro, Emil F.

2012-01-01

The vast majority of studies that have examined the latent structure of attention deficit/hyperactivity disorder (ADHD) in children and adolescents have concluded that ADHD has a dimensional latent structure. In other words, ADHD symptomatology exists along a continuum and there is no natural boundary or qualitative distinction (i.e., taxon) separating youth with ADHD from those with subclinical inattention or hyperactivity/impulsivity problems. Although adult ADHD appears to be less prevalent than ADHD in youth (which could suggest a more severe adult ADHD taxon), researchers have yet to examine the latent structure of ADHD in adults. The present study used a sample (N = 600) of adults who completed a self-report measure of ADHD symptoms. The taxometric analyses revealed a dimensional latent structure for inattention, hyperactivity/impulsivity, and ADHD. These findings are consistent with previous taxometric studies that examined ADHD in children and adolescents, and with contemporary polygenic and multifactorial models of ADHD. PMID:22480749

Alexithymia and psychosocial problems among Italian preadolescents. A latent class analysis approach.

Science.gov (United States)

Mannarini, Stefania; Balottin, Laura; Toldo, Irene; Gatta, Michela

2016-10-01

The study, conducted on Italian preadolscents aged 11 to 13 belonging to the general population, aims to investigate the relationship between the emotional functioning, namely, alexithymia, and the risk of developing behavioral and emotional problems measured using the Strength and Difficulty Questionnaire. The latent class analysis approach allowed to identify two latent variables, accounting for the internalizing (emotional symptoms and difficulties in emotional awareness) and for the externalizing problems (conduct problems and hyperactivity, problematic relationships with peers, poor prosocial behaviors and externally oriented thinking). The two latent variables featured two latent classes: the difficulty in dealing with problems and the strength to face problems that was representative of most of the healthy participants with specific gender differences. Along with the analysis of psychopathological behaviors, the study of resilience and strengths can prove to be a key step in order to develop valuable preventive approaches to tackle psychiatric disorders. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

The latent structure of attention deficit/hyperactivity disorder in an adult sample.

Science.gov (United States)

Marcus, David K; Norris, Alyssa L; Coccaro, Emil F

2012-06-01

The vast majority of studies that have examined the latent structure of attention deficit/hyperactivity disorder (ADHD) in children and adolescents have concluded that ADHD has a dimensional latent structure. In other words, ADHD symptomatology exists along a continuum and there is no natural boundary or qualitative distinction (i.e., taxon) separating youth with ADHD from those with subclinical inattention or hyperactivity/impulsivity problems. Although adult ADHD appears to be less prevalent than ADHD in youth (which could suggest a more severe adult ADHD taxon), researchers have yet to examine the latent structure of ADHD in adults. The present study used a sample (N = 600) of adults who completed a self-report measure of ADHD symptoms. The taxometric analyses revealed a dimensional latent structure for inattention, hyperactivity/impulsivity, and ADHD. These findings are consistent with previous taxometric studies that examined ADHD in children and adolescents, and with contemporary polygenic and multifactorial models of ADHD. Copyright © 2012 Elsevier Ltd. All rights reserved.

New Treatment Regimen for Latent Tuberculosis Infection

Centers for Disease Control (CDC) Podcasts

In this podcast, Dr. Kenneth Castro, Director of the Division of Tuberculosis Elimination, discusses the December 9, 2011 CDC guidelines for the use of a new regimen for the treatment of persons with latent tuberculosis infection.

Forensic Discrimination of Latent Fingerprints Using Laser-Induced Breakdown Spectroscopy (LIBS) and Chemometric Approaches.

Science.gov (United States)

Yang, Jun-Ho; Yoh, Jack J

2018-01-01

A novel technique is reported for separating overlapping latent fingerprints using chemometric approaches that combine laser-induced breakdown spectroscopy (LIBS) and multivariate analysis. The LIBS technique provides the capability of real time analysis and high frequency scanning as well as the data regarding the chemical composition of overlapping latent fingerprints. These spectra offer valuable information for the classification and reconstruction of overlapping latent fingerprints by implementing appropriate statistical multivariate analysis. The current study employs principal component analysis and partial least square methods for the classification of latent fingerprints from the LIBS spectra. This technique was successfully demonstrated through a classification study of four distinct latent fingerprints using classification methods such as soft independent modeling of class analogy (SIMCA) and partial least squares discriminant analysis (PLS-DA). The novel method yielded an accuracy of more than 85% and was proven to be sufficiently robust. Furthermore, through laser scanning analysis at a spatial interval of 125 µm, the overlapping fingerprints were reconstructed as separate two-dimensional forms.

In vivo colocalization of 2-nitroimidazole EF5 fluorescence intensity and electron paramagnetic resonance oximetry in mouse tumors

International Nuclear Information System (INIS)

Mahy, Pierre; Bast, Marc de; Gallez, Bernard; Gueulette, John; Koch, Cameron J.; Scalliet, Pierre; Gregoire, Vincent

2003-01-01

Background and purpose: The primary objective of this study was to establish in vivo the relationship between 2-2-nitro-1H-imidazol-1yl-N-(2,2,3,3,3-pentafluoropropyl)-acetamide (EF5) adduct formation and intratumoral oxygen concentrations measured by electron paramagnetic resonance (EPR) in a tumor model mimicking a clinical situation. The secondary objective was an attempt to calibrate in situ the immunofluorescence (IF) signal with EPR oximetry. Materials and methods: IM syngeneic fibrosarcoma (NFSA) bearing C3H mice were used. Three days after injection of a paramagnetic charcoal into the tumor, the mice were anesthetized, injected with the hypoxic marker EF5, and monitored every 20 min for 3 h with a low-frequency EPR spectrometer. Animals were allowed to breath either under 21 or 100% O 2 . Tumors were then harvested, frozen, cut into sections including the charcoal and processed for EF5 adducts detection using monoclonal antibodies. Slices were viewed with a fluorescence microscope and 190x140 μm areas surrounding the charcoal were digitized and analyzed with the NIH-Image and Adobe Photoshop TM software. The fluorescence intensity (FI) was measured in the whole pictures and in strips of 10 μm around the charcoal. Results: EF5 binding increased with decreasing pO 2 , most substantially at pO 2 below 5 mm Hg. Baseline (ambient air) pO 2 reached 3.2±2.1 mm Hg in NFSA tumors. It increased to 9.8±3.2 mm Hg under 100% O 2 . A statistically significant correlation was observed on an individual tumor basis between the FI in the first 10 μm strip around the charcoal and the pO 2 determined by EPR oximetry (Wilcoxon signed rank test: P 2 in an in vivo environment under biologically-relevant pO 2 values of less than 10 mm Hg

Reward devaluation disrupts latent inhibition in fear conditioning.

Science.gov (United States)

De la Casa, Luís Gonzalo; Mena, Auxiliadora; Ruiz-Salas, Juán Carlos; Quintero, Esperanza; Papini, Mauricio R

2018-03-01

Three experiments explored the link between reward shifts and latent inhibition (LI). Using consummatory procedures, rewards were either downshifted from 32% to 4% sucrose (Experiments 1-2), or upshifted from 4% to 32% sucrose (Experiment 3). In both cases, appropriate unshifted controls were also included. LI was implemented in terms of fear conditioning involving a single tone-shock pairing after extensive tone-only preexposure. Nonpreexposed controls were also included. Experiment 1 demonstrated a typical LI effect (i.e., disruption of fear conditioning after preexposure to the tone) in animals previously exposed only to 4% sucrose. However, the LI effect was eliminated by preexposure to a 32%-to-4% sucrose devaluation. Experiment 2 replicated this effect when the LI protocol was administered immediately after the reward devaluation event. However, LI was restored when preexposure was administered after a 60-min retention interval. Finally, Experiment 3 showed that a reward upshift did not affect LI. These results point to a significant role of negative emotion related to reward devaluation in the enhancement of stimulus processing despite extensive nonreinforced preexposure experience.

Space-time latent component Modeling of Geo-referenced health data

OpenAIRE

Lawson, Andrew B.; Song, Hae-Ryoung; Cai, Bo; Hossain, Md Monir; Huang, Kun

2010-01-01

Latent structure models have been proposed in many applications. For space time health data it is often important to be able to find underlying trends in time which are supported by subsets of small areas. Latent structure modeling is one approach to this analysis. This paper presents a mixture-based approach that can be appied to component selction. The analysis of a Georgia ambulatory asthma county level data set is presented and a simulation-based evaluation is made.

Translating latent trends in food consumer behavior into new products

OpenAIRE

Gellynck, Xavier; Kühne, Bianka; Van Wezemael, Lynn; Verbeke, Wim

2010-01-01

For successful product development it is important to explore the latent changes in consumer behavior prior to the product development process. The identification of a latent trend before the manifestation moment can be achieved by trend analysis. Trend analysis delivers insights that explore the future in order to identify prospective consumers and new product ideas, but also includes a feeling for the currents in market and technology. Hence, the aim is to identify emerging weak signals in ...

Estimators for longitudinal latent exposure models: examining measurement model assumptions.

Science.gov (United States)

Sánchez, Brisa N; Kim, Sehee; Sammel, Mary D

2017-06-15

Latent variable (LV) models are increasingly being used in environmental epidemiology as a way to summarize multiple environmental exposures and thus minimize statistical concerns that arise in multiple regression. LV models may be especially useful when multivariate exposures are collected repeatedly over time. LV models can accommodate a variety of assumptions but, at the same time, present the user with many choices for model specification particularly in the case of exposure data collected repeatedly over time. For instance, the user could assume conditional independence of observed exposure biomarkers given the latent exposure and, in the case of longitudinal latent exposure variables, time invariance of the measurement model. Choosing which assumptions to relax is not always straightforward. We were motivated by a study of prenatal lead exposure and mental development, where assumptions of the measurement model for the time-changing longitudinal exposure have appreciable impact on (maximum-likelihood) inferences about the health effects of lead exposure. Although we were not particularly interested in characterizing the change of the LV itself, imposing a longitudinal LV structure on the repeated multivariate exposure measures could result in high efficiency gains for the exposure-disease association. We examine the biases of maximum likelihood estimators when assumptions about the measurement model for the longitudinal latent exposure variable are violated. We adapt existing instrumental variable estimators to the case of longitudinal exposures and propose them as an alternative to estimate the health effects of a time-changing latent predictor. We show that instrumental variable estimators remain unbiased for a wide range of data generating models and have advantages in terms of mean squared error. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Perceptions of care in women sent home in latent labor.

Science.gov (United States)

Hosek, Claire; Faucher, Mary Ann; Lankford, Janice; Alexander, James

2014-01-01

To assess perceptions of care from woman discharged from an obstetrical (OB) triage unit or a labor and delivery unit with a diagnosis of false or latent labor in order to determine factors that may increase or decrease the woman's satisfaction with care. Descriptive, convenience sample. One hundred low-income pregnant women at term presenting for care in latent labor consented to participate in a telephone survey. The survey was based on the relevant research about care of women in early labor and the Donabedian quality improvement framework assessing structure, process, and outcomes of care. Forty-one percent of women did not want to be discharged home in latent labor. Common reasons included women stating they were in too much pain or they were living too far from the birth setting. Eating, drinking, and comfort measures were the most common measures women cited that would have made them feel better when in the hospital. A reoccurring response from women was their desire for very clear and specific written instructions about how to stay comfortable at home and when to return to the hospital. Comfort measures in the birth setting, including in triage, should include a variety of options including ambulation and oral nutrition. Detailed and specific written instructions about early labor and staying comfortable while at home have value for women in this survey regarding their perceptions of care. Results from this survey of low-income women suggest that a subset of women in latent labor just do not want to go home and this may be related to having too much pain and/or travel distance to the hospital. Hospital birth settings also have an opportunity to create a care environment that provides services and embodies attributes that women report as important for their satisfaction with care in latent labor.

Systematic identification of latent disease-gene associations from PubMed articles.

Science.gov (United States)

Zhang, Yuji; Shen, Feichen; Mojarad, Majid Rastegar; Li, Dingcheng; Liu, Sijia; Tao, Cui; Yu, Yue; Liu, Hongfang

2018-01-01

Recent scientific advances have accumulated a tremendous amount of biomedical knowledge providing novel insights into the relationship between molecular and cellular processes and diseases. Literature mining is one of the commonly used methods to retrieve and extract information from scientific publications for understanding these associations. However, due to large data volume and complicated associations with noises, the interpretability of such association data for semantic knowledge discovery is challenging. In this study, we describe an integrative computational framework aiming to expedite the discovery of latent disease mechanisms by dissecting 146,245 disease-gene associations from over 25 million of PubMed indexed articles. We take advantage of both Latent Dirichlet Allocation (LDA) modeling and network-based analysis for their capabilities of detecting latent associations and reducing noises for large volume data respectively. Our results demonstrate that (1) the LDA-based modeling is able to group similar diseases into disease topics; (2) the disease-specific association networks follow the scale-free network property; (3) certain subnetwork patterns were enriched in the disease-specific association networks; and (4) genes were enriched in topic-specific biological processes. Our approach offers promising opportunities for latent disease-gene knowledge discovery in biomedical research.

Non-destructive forensic latent fingerprint acquisition with chromatic white light sensors

Science.gov (United States)

Leich, Marcus; Kiltz, Stefan; Dittmann, Jana; Vielhauer, Claus

2011-02-01

Non-destructive latent fingerprint acquisition is an emerging field of research, which, unlike traditional methods, makes latent fingerprints available for additional verification or further analysis like tests for substance abuse or age estimation. In this paper a series of tests is performed to investigate the overall suitability of a high resolution off-the-shelf chromatic white light sensor for the contact-less and non-destructive latent fingerprint acquisition. Our paper focuses on scanning previously determined regions with exemplary acquisition parameter settings. 3D height field and reflection data of five different latent fingerprints on six different types of surfaces (HDD platter, brushed metal, painted car body (metallic and non-metallic finish), blued metal, veneered plywood) are experimentally studied. Pre-processing is performed by removing low-frequency gradients. The quality of the results is assessed subjectively; no automated feature extraction is performed. Additionally, the degradation of the fingerprint during the acquisition period is observed. While the quality of the acquired data is highly dependent on surface structure, the sensor is capable of detecting the fingerprint on all sample surfaces. On blued metal the residual material is detected; however, the ridge line structure dissolves within minutes after fingerprint placement.

Reactivation of Latent HIV-1 Expression by Engineered TALE Transcription Factors.

Science.gov (United States)

Perdigão, Pedro; Gaj, Thomas; Santa-Marta, Mariana; Barbas, Carlos F; Goncalves, Joao

2016-01-01

The presence of replication-competent HIV-1 -which resides mainly in resting CD4+ T cells--is a major hurdle to its eradication. While pharmacological approaches have been useful for inducing the expression of this latent population of virus, they have been unable to purge HIV-1 from all its reservoirs. Additionally, many of these strategies have been associated with adverse effects, underscoring the need for alternative approaches capable of reactivating viral expression. Here we show that engineered transcriptional modulators based on customizable transcription activator-like effector (TALE) proteins can induce gene expression from the HIV-1 long terminal repeat promoter, and that combinations of TALE transcription factors can synergistically reactivate latent viral expression in cell line models of HIV-1 latency. We further show that complementing TALE transcription factors with Vorinostat, a histone deacetylase inhibitor, enhances HIV-1 expression in latency models. Collectively, these findings demonstrate that TALE transcription factors are a potentially effective alternative to current pharmacological routes for reactivating latent virus and that combining synthetic transcriptional activators with histone deacetylase inhibitors could lead to the development of improved therapies for latent HIV-1 infection.

Reactivation of Latent HIV-1 Expression by Engineered TALE Transcription Factors.

Directory of Open Access Journals (Sweden)

Pedro Perdigão

Full Text Available The presence of replication-competent HIV-1 -which resides mainly in resting CD4+ T cells--is a major hurdle to its eradication. While pharmacological approaches have been useful for inducing the expression of this latent population of virus, they have been unable to purge HIV-1 from all its reservoirs. Additionally, many of these strategies have been associated with adverse effects, underscoring the need for alternative approaches capable of reactivating viral expression. Here we show that engineered transcriptional modulators based on customizable transcription activator-like effector (TALE proteins can induce gene expression from the HIV-1 long terminal repeat promoter, and that combinations of TALE transcription factors can synergistically reactivate latent viral expression in cell line models of HIV-1 latency. We further show that complementing TALE transcription factors with Vorinostat, a histone deacetylase inhibitor, enhances HIV-1 expression in latency models. Collectively, these findings demonstrate that TALE transcription factors are a potentially effective alternative to current pharmacological routes for reactivating latent virus and that combining synthetic transcriptional activators with histone deacetylase inhibitors could lead to the development of improved therapies for latent HIV-1 infection.

Are depression and frailty overlapping syndromes in mid- and late-life? A latent variable analysis.

Science.gov (United States)

Mezuk, Briana; Lohman, Matthew; Dumenci, Levent; Lapane, Kate L

2013-06-01

Depression and frailty both predict disability and morbidity in later life. However, it is unclear to what extent these common geriatric syndromes represent overlapping constructs. To examine the joint relationship between the constructs of depression and frailty. Data come from 2004-2005 wave of the Baltimore Epidemiologic Catchment Area Study, and the analysis is limited to participants 40 years and older, with complete data on frailty and depression indicators (N = 683). Depression was measured using the Diagnostic Interview Schedule, and frailty was indexed by modified Fried criteria. A series of confirmatory latent class analyses were used to assess the degree to which depression and frailty syndromes identify the same populations. A latent kappa coefficient (κl) was also estimated between the constructs. Confirmatory latent class analyses indicated that depression and frailty represent distinct syndromes rather than a single construct. The joint modeling of the two constructs supported a three-class solution for depression and two-class solution for frailty, with 2.9% categorized as severely depressed, 19.4% as mildly depressed, and 77.7% as not depressed, and 21.1% categorized as frail and 78.9% as not frail. The chance-corrected agreement statistic indicated moderate correspondence between the depression and frailty constructs (κl: 66, 95% confidence interval: 0.58-0.74). Results suggest that depression and frailty are interrelated concepts, yet their operational criteria identify substantively overlapping subpopulations. These findings have implications for understanding factors that contribute to the etiology and prognosis of depression and frailty in later life. Copyright © 2013 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

Spitzer IRS Spectroscopy of the 10 Myr-Old EF Cha Debris Disk: Evidence for Phyllosilicate-Rich Dust in the Terrestrial Zone

Science.gov (United States)

Currie, Thayne; Lisse, Carey M.; Sicillia-Aguilar, Aurora; Rieke, George H.; Su, Kate Y. L.

2011-01-01

We describe Spitzer IRS spectroscopic observations of the approx. 10 Myr-old star, EF Chao Compositional modeling of the spectra from 5 micron to 35 micron confirms that it is surrounded by a luminous debris disk with L(sub D)/L(sub *) approx. 10(exp -3), containing dust with temperatures between 225 K and 430 K characteristic of the terrestrial zone. The EF Cha spectrum shows evidence for many solid-state features, unlike most cold, low-luminosity debris disks but like some other 10-20 Myr-old luminous, warm debris disks (e.g. HD 113766A). The EF Cha debris disk is unusually rich in a species or combination of species whose emissivities resemble that of finely-powdered, laboratory-measured phyllosilicate species (talc, saponite, and smectite), which are likely produced by aqueous alteration of primordial anhydrous rocky materials. The dust and, by inference, the parent bodies of the debris also contain abundant amorphous silicates and metal sulfides, and possibly water ice. The dust's total olivine to pyroxene ratio of approx. 2 also provides evidence of aqueous alteration. The large mass volume of grains with sizes comparable to or below the radiation blow-out limit implies that planetesimals may be colliding at a rate high enough to yield the emitting dust but not so high as to devolatize the planetesimals via impact processing. Because phyllosilicates are produced by the interactions between anhydrous rock and warm, reactive water, EF Cha's disk is a likely signpost for water delivery to the terrestrial zone of a young planetary system.

Latent Heat Storage Through Phase Change Materials

Indian Academy of Sciences (India)

IAS Admin

reducing storage volume for different materials. The examples are numerous: ... Latent heat is an attractive way to store solar heat as it provides high energy storage density, .... Maintenance of the PCM treated fabric is easy. The melted PCM.

Stress-induced light scattering method for the detection of latent flaws on fine polished glass substrates.

Science.gov (United States)

Sakata, Y; Sakai, K; Nonaka, K

2014-08-01

Fine polishing techniques, such as the chemical mechanical polishing treatment, are one of the most important technique to glass substrate manufacturing. Mechanical interaction in the form of friction occurs between the abrasive and the substrate surface during polishing, which may cause formation of latent flaws on the glass substrate surface. Fine polishing-induced latent flaws may become obvious during a subsequent cleaning process if glass surfaces are corroded away by chemical interaction with the cleaning liquid. Latent flaws thus reduce product yield. In general, non-destructive inspection techniques, such as the light-scattering methods, used to detect foreign matters on the glass substrate surface. However, it is difficult to detect latent flaws by these methods because the flaws remain closed. Authors propose a novel inspection technique for fine polishing-induced latent flaws by combining the light scattering method with stress effects, referred to as the stress-induced light scattering method (SILSM). SILSM is able to distinguish between latent flaws and particles on the surface. In this method, samples are deformed by an actuator and stress effects are induced around the tips of latent flaws. Due to the photoelastic effect, the refractive index of the material around the tip of a latent flaw is changed. This changed refractive index is in turn detected by a cooled charge-coupled device camera as variations in light scattering intensity. In this report, surface latent flaws are detected non-destructively by applying SILSM to glass substrates, and the utility of SILSM evaluated as a novel inspection technique.

Repeatability and reproducibility of decisions by latent fingerprint examiners.

Directory of Open Access Journals (Sweden)

Bradford T Ulery

Full Text Available The interpretation of forensic fingerprint evidence relies on the expertise of latent print examiners. We tested latent print examiners on the extent to which they reached consistent decisions. This study assessed intra-examiner repeatability by retesting 72 examiners on comparisons of latent and exemplar fingerprints, after an interval of approximately seven months; each examiner was reassigned 25 image pairs for comparison, out of total pool of 744 image pairs. We compare these repeatability results with reproducibility (inter-examiner results derived from our previous study. Examiners repeated 89.1% of their individualization decisions, and 90.1% of their exclusion decisions; most of the changed decisions resulted in inconclusive decisions. Repeatability of comparison decisions (individualization, exclusion, inconclusive was 90.0% for mated pairs, and 85.9% for nonmated pairs. Repeatability and reproducibility were notably lower for comparisons assessed by the examiners as "difficult" than for "easy" or "moderate" comparisons, indicating that examiners' assessments of difficulty may be useful for quality assurance. No false positive errors were repeated (n = 4; 30% of false negative errors were repeated. One percent of latent value decisions were completely reversed (no value even for exclusion vs. of value for individualization. Most of the inter- and intra-examiner variability concerned whether the examiners considered the information available to be sufficient to reach a conclusion; this variability was concentrated on specific image pairs such that repeatability and reproducibility were very high on some comparisons and very low on others. Much of the variability appears to be due to making categorical decisions in borderline cases.

Prevalence of latent alpha-herpesviruses in Thoroughbred racing horses.

Science.gov (United States)

Pusterla, Nicola; Mapes, Samantha; David Wilson, W

2012-08-01

The objective of this study was to detect and characterize latent equine herpes virus (EHV)-1 and -4 from the submandibular (SMLN) and bronchial lymph (BLN) nodes, as well as from the trigeminal ganglia (TG) of 70 racing Thoroughbred horses submitted for necropsy following sustaining serious musculoskeletal injuries while racing. A combination of nucleic acid precipitation and pre-amplification steps was used to increase analytical sensitivity. Tissues were deemed positive for latent EHV-1 and/or -4 infection when found PCR positive for the corresponding glycoprotein B (gB) gene in the absence of detectable late structural protein gene (gB gene) mRNA. The EHV-1 genotype was also determined using a discriminatory real-time PCR assay targeting the DNA polymerase gene (ORF 30). Eighteen (25.7%) and 58 (82.8%) horses were PCR positive for the gB gene of EHV-1 and -4, respectively, in at least one of the three tissues sampled. Twelve horses were dually infected with EHV-1 and -4, two carried a latent neurotropic strain of EHV-1, six carried a non-neurotropic genotype of EHV-1 and 10 were dually infected with neurotropic and non-neurotropic EHV-1. The distribution of latent EHV-1 and -4 infection varied in the samples, with the TG found to be most commonly infected. Overall, non-neurotropic strains were more frequently detected than neurotropic strains, supporting the general consensus that non-neurotropic strains are more prevalent in horse populations, and hence the uncommon occurrence of equine herpes myeloencephalopathy. Copyright © 2012 Elsevier Ltd. All rights reserved.

Climate forcing and response to idealized changes in surface latent and sensible heat

International Nuclear Information System (INIS)

Ban-Weiss, George A; Cao Long; Pongratz, Julia; Caldeira, Ken; Bala, Govindasamy

2011-01-01

Land use and land cover changes affect the partitioning of latent and sensible heat, which impacts the broader climate system. Increased latent heat flux to the atmosphere has a local cooling influence known as 'evaporative cooling', but this energy will be released back to the atmosphere wherever the water condenses. However, the extent to which local evaporative cooling provides a global cooling influence has not been well characterized. Here, we perform a highly idealized set of climate model simulations aimed at understanding the effects that changes in the balance between surface sensible and latent heating have on the global climate system. We find that globally adding a uniform 1 W m -2 source of latent heat flux along with a uniform 1 W m -2 sink of sensible heat leads to a decrease in global mean surface air temperature of 0.54 ± 0.04 K. This occurs largely as a consequence of planetary albedo increases associated with an increase in low elevation cloudiness caused by increased evaporation. Thus, our model results indicate that, on average, when latent heating replaces sensible heating, global, and not merely local, surface temperatures decrease.

Transcriptional regulation of latent feline immunodeficiency virus in peripheral CD4+ T-lymphocytes.

Science.gov (United States)

McDonnel, Samantha J; Sparger, Ellen E; Luciw, Paul A; Murphy, Brian G

2012-05-01

Feline immunodeficiency virus (FIV), the lentivirus of domestic cats responsible for feline AIDS, establishes a latent infection in peripheral blood CD4+ T-cells approximately eight months after experimental inoculation. In this study, cats experimentally infected with the FIV-C strain in the asymptomatic phase demonstrated an estimated viral load of 1 infected cell per approximately 10(3) CD4+ T-cells, with about 1 copy of viral DNA per cell. Approximately 1 in 10 proviral copies was capable of transcription in the asymptomatic phase. The latent FIV proviral promoter was associated with deacetylated, methylated histones, which is consistent with a condensed chromatin structure. In contrast, the transcriptionally active FIV promoter was associated with histone acetylation and demethylation. In addition, RNA polymerase II appeared to be paused on the latent viral promoter, and short promoter-proximal transcripts were detected. Our findings for the FIV promoter in infected cats are similar to results obtained in studies of human immunodeficiency virus (HIV)-1 latent proviruses in cell culture in vitro studies. Thus, the FIV/cat model may offer insights into in vivo mechanisms of HIV latency and provides a unique opportunity to test novel therapeutic interventions aimed at eradicating latent virus.

Changes in latent fingerprint examiners' markup between analysis and comparison.

Science.gov (United States)

Ulery, Bradford T; Hicklin, R Austin; Roberts, Maria Antonia; Buscaglia, JoAnn

2015-02-01

After the initial analysis of a latent print, an examiner will sometimes revise the assessment during comparison with an exemplar. Changes between analysis and comparison may indicate that the initial analysis of the latent was inadequate, or that confirmation bias may have affected the comparison. 170 volunteer latent print examiners, each randomly assigned 22 pairs of prints from a pool of 320 total pairs, provided detailed markup documenting their interpretations of the prints and the bases for their comparison conclusions. We describe changes in value assessments and markup of features and clarity. When examiners individualized, they almost always added or deleted minutiae (90.3% of individualizations); every examiner revised at least some markups. For inconclusive and exclusion determinations, changes were less common, and features were added more frequently when the image pair was mated (same source). Even when individualizations were based on eight or fewer corresponding minutiae, in most cases some of those minutiae had been added during comparison. One erroneous individualization was observed: the markup changes were notably extreme, and almost all of the corresponding minutiae had been added during comparison. Latents assessed to be of value for exclusion only (VEO) during analysis were often individualized when compared to a mated exemplar (26%); in our previous work, where examiners were not required to provide markup of features, VEO individualizations were much less common (1.8%). Published by Elsevier Ireland Ltd.

Fitting and interpreting continuous-time latent Markov models for panel data.

Science.gov (United States)

Lange, Jane M; Minin, Vladimir N

2013-11-20

Multistate models characterize disease processes within an individual. Clinical studies often observe the disease status of individuals at discrete time points, making exact times of transitions between disease states unknown. Such panel data pose considerable modeling challenges. Assuming the disease process progresses accordingly, a standard continuous-time Markov chain (CTMC) yields tractable likelihoods, but the assumption of exponential sojourn time distributions is typically unrealistic. More flexible semi-Markov models permit generic sojourn distributions yet yield intractable likelihoods for panel data in the presence of reversible transitions. One attractive alternative is to assume that the disease process is characterized by an underlying latent CTMC, with multiple latent states mapping to each disease state. These models retain analytic tractability due to the CTMC framework but allow for flexible, duration-dependent disease state sojourn distributions. We have developed a robust and efficient expectation-maximization algorithm in this context. Our complete data state space consists of the observed data and the underlying latent trajectory, yielding computationally efficient expectation and maximization steps. Our algorithm outperforms alternative methods measured in terms of time to convergence and robustness. We also examine the frequentist performance of latent CTMC point and interval estimates of disease process functionals based on simulated data. The performance of estimates depends on time, functional, and data-generating scenario. Finally, we illustrate the interpretive power of latent CTMC models for describing disease processes on a dataset of lung transplant patients. We hope our work will encourage wider use of these models in the biomedical setting. Copyright © 2013 John Wiley & Sons, Ltd.

Examination of the change in latent statuses in bullying behaviors across time.

Science.gov (United States)

Ryoo, Ji Hoon; Wang, Cixin; Swearer, Susan M

2015-03-01

Involvement in bullying and victimization has been mostly studied using cross-sectional data from 1 time point. As such, much of our understanding of bullying and victimization has not captured the dynamic experiences of youth over time. To examine the change of latent statuses in bullying and victimization, we applied latent transition analysis examining self-reported bullying involvement from 1,180 students in 5th through 9th grades across 3 time points. We identified unobserved heterogeneous subgroups (i.e., latent statuses) and investigated how students transition between the unobserved subgroups over time. For victimization, 4 latent statuses were identified: frequent victim (11.23%), occasional traditional victim (28.86%), occasional cyber and traditional victim (10.34%), and infrequent victim (49.57%). For bullying behavior, 3 latent statuses were identified: frequent perpetrator (5.12%), occasional verbal/relational perpetrator (26.04%), and infrequent perpetrator (68.84%). The characteristics of the transitions were examined. The multiple-group effects of gender, grade, and first language learned on transitions across statuses were also investigated. The infrequent victim and infrequent perpetrator groups were the most stable, and the frequent victim and frequent perpetrator groups were the least stable. These findings suggest instability in perpetration and victimization over time, as well as significant changes, especially during school transition years. Findings suggest that school-based interventions need to address the heterogeneity in perpetrator and victim experiences in adolescence.

Rapid quantification of the latent reservoir for HIV-1 using a viral outgrowth assay.

Directory of Open Access Journals (Sweden)

Gregory M Laird

Full Text Available HIV-1 persists in infected individuals in a stable pool of resting CD4(+ T cells as a latent but replication-competent provirus. This latent reservoir is the major barrier to the eradication of HIV-1. Clinical trials are currently underway investigating the effects of latency-disrupting compounds on the persistence of the latent reservoir in infected individuals. To accurately assess the effects of such compounds, accurate assays to measure the frequency of latently infected cells are essential. The development of a simpler assay for the latent reservoir has been identified as a major AIDS research priority. We report here the development and validation of a rapid viral outgrowth assay that quantifies the frequency of cells that can release replication-competent virus following cellular activation. This new assay utilizes bead and column-based purification of resting CD4(+ T cells from the peripheral blood of HIV-1 infected patients rather than cell sorting to obtain comparable resting CD4(+ T cell purity. This new assay also utilizes the MOLT-4/CCR5 cell line for viral expansion, producing statistically comparable measurements of the frequency of latent HIV-1 infection. Finally, this new assay employs a novel quantitative RT-PCR specific for polyadenylated HIV-1 RNA for virus detection, which we demonstrate is a more sensitive and cost-effective method to detect HIV-1 replication than expensive commercial ELISA detection methods. The reductions in both labor and cost make this assay suitable for quantifying the frequency of latently infected cells in clinical trials of HIV-1 eradication strategies.

LATENT STRUCTURE OF MOTOR ABILITIES AND SKILLS OF DEAF CHILDREN

Directory of Open Access Journals (Sweden)

Husnija Hasanbegović

2012-04-01

Full Text Available In this work surveys of latent motility abilities and skills of school children are shown. The sample for this survey was consisted of two subsamples. First one has consisted of deaf children N=29, and the second one has consisted hearing children of same age N=69. Subsamples of deaf is chosen according to model of applied sample, and subsample is chosen randomly, so two stages group sample N=90 has been created. After quantitative differences have been discovered between subsamples, hearing pupils have shown statistically better results at motility skills and techniques than deaf children and cumulative results have been subjected to inter correlation of variables. The target of using this method was determination of saturation of common variability through saturation of variables and their correlation by Ortoblique rotation for determination of latent information that are going to serve as practical guides at education and deaf children treatment, because of improvement of their motility abilities and skills according to hearing children. Three factors have been singled out as main preview of measurement on manifest variables. According to first review of measuring it has been established that at deaf children is needed to work on improving of physical abilities and mobility and then developed motility abilities and skills. Their information has been gained most probably by non system fluctuations as information about ability of balance maintaining which is most probably non dependable of motility abilities and skills as at deaf and hearing children too. According to this survey by entering the structure of measuring instrument it is possible to create programs for improving motility abilities and skills at deaf children.

Determination of tumour hypoxia with the PET tracer [18F]EF3: improvement of the tumour-to-background ratio in a mouse tumour model

International Nuclear Information System (INIS)

Christian, Nicolas; Bol, Anne; Bast, Marc de; Labar, Daniel; Lee, John; Mahy, Pierre; Gregoire, Vincent

2007-01-01

The 2-(2-nitroimidazol-1-yl)-N-(3,3,3-trifluoropropyl)acetamide (EF3) is a 2-nitroimidazole derivative which undergoes bioreductive activation under hypoxic conditions. Using the PET tracer [ 18 F]EF3 in mice, tumour-to-muscle ratios ranging from 1.3 to 3.5 were observed. This study investigated the impact of various interventions aimed at increasing [ 18 F]EF3 elimination, thus potentially increasing the tumour-to-noise ratio in mice, by increasing the renal filtration rate (spironolactone, furosemide), decreasing tubular re-absorption (metronidazole, ornidazole, amino acid solution) or stimulating gastro-intestinal elimination (phenobarbital). C3H mice were injected i.v. with an average of 12.95 MBq of [ 18 F]EF3. Drugs were injected i.v. 15 min before the tracer or daily 4 days prior to the experiment (phenobarbital). Anaesthetised mice were imaged from 30 to 300 min with a dedicated animal PET (Mosaic, Philips). Regions of interest were delineated around the tumour, bladder, heart, liver and leg muscle. Radioactivity was expressed as a percentage of injected activity per gram of tissue. Ornidazole decreased the urinary excretion and increased the liver uptake of [ 18 F]EF3, but without causing any changes in the other organs. Phenobarbital significantly increased the liver concentration and decreased radioactivity in blood and muscle without affecting the tracer uptake in tumour. Consequently, a small but non-significant increase in tumour-to-noise ratio was observed. Although some effects were observed with other drugs, they did not modify the tumour-to-noise ratio. Only phenobarbital induced a trend toward an increased tumour-to-noise ratio that could possibly be tested in the clinical situation. (orig.)

Using a single tablet daily to treat latent tuberculosis infection in Brazil: bioequivalence of two different isoniazid formulations (300 mg and 100 mg) demonstrated by a sensitive and rapid high-performance liquid chromatography-tandem mass spectrometry method in a randomised, crossover study.

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Daher, André; Pitta, Luciana; Santos, Tereza; Barreira, Draurio; Pinto, Douglas

2015-06-01

The recommended treatment for latent tuberculosis (TB) infection in adults is a daily dose of isoniazid (INH) 300 mg for six months. In Brazil, INH was formulated as 100 mg tablets. The treatment duration and the high pill burden compromised patient adherence to the treatment. The Brazilian National Programme for Tuberculosis requested a new 300 mg INH formulation. The aim of our study was to compare the bioavailability of the new INH 300 mg formulation and three 100 mg tablets of the reference formulation. We conducted a randomised, single dose, open label, two-phase crossover bioequivalence study in 28 healthy human volunteers. The 90% confidence interval for the INH maximum concentration of drug observed in plasma and area under the plasma concentration vs. time curve from time zero to the last measurable concentration "time t" was 89.61-115.92 and 94.82-119.44, respectively. The main limitation of our study was that neither adherence nor the safety profile of multiple doses was evaluated. To determine the level of INH in human plasma, we developed and validated a sensitive, simple and rapid high-performance liquid chromatography-tandem mass spectrometry method. Our results showed that the new formulation was bioequivalent to the 100 mg reference product. This finding supports the use of a single 300 mg tablet daily strategy to treat latent TB. This new formulation may increase patients' adherence to the treatment and quality of life.

Using a single tablet daily to treat latent tuberculosis infection in Brazil: bioequivalence of two different isoniazid formulations (300 mg and 100 mg demonstrated by a sensitive and rapid high-performance liquid chromatography-tandem mass spectrometry method in a randomised, crossover study

Directory of Open Access Journals (Sweden)

André Daher

2015-06-01

Full Text Available The recommended treatment for latent tuberculosis (TB infection in adults is a daily dose of isoniazid (INH 300 mg for six months. In Brazil, INH was formulated as 100 mg tablets. The treatment duration and the high pill burden compromised patient adherence to the treatment. The Brazilian National Programme for Tuberculosis requested a new 300 mg INH formulation. The aim of our study was to compare the bioavailability of the new INH 300 mg formulation and three 100 mg tablets of the reference formulation. We conducted a randomised, single dose, open label, two-phase crossover bioequivalence study in 28 healthy human volunteers. The 90% confidence interval for the INH maximum concentration of drug observed in plasma and area under the plasma concentration vs. time curve from time zero to the last measurable concentration “time t” was 89.61-115.92 and 94.82-119.44, respectively. The main limitation of our study was that neither adherence nor the safety profile of multiple doses was evaluated. To determine the level of INH in human plasma, we developed and validated a sensitive, simple and rapid high-performance liquid chromatography-tandem mass spectrometry method. Our results showed that the new formulation was bioequivalent to the 100 mg reference product. This finding supports the use of a single 300 mg tablet daily strategy to treat latent TB. This new formulation may increase patients’ adherence to the treatment and quality of life.

Modeling associations between latent event processes governing time series of pulsing hormones.

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Liu, Huayu; Carlson, Nichole E; Grunwald, Gary K; Polotsky, Alex J

2017-10-31

This work is motivated by a desire to quantify relationships between two time series of pulsing hormone concentrations. The locations of pulses are not directly observed and may be considered latent event processes. The latent event processes of pulsing hormones are often associated. It is this joint relationship we model. Current approaches to jointly modeling pulsing hormone data generally assume that a pulse in one hormone is coupled with a pulse in another hormone (one-to-one association). However, pulse coupling is often imperfect. Existing joint models are not flexible enough for imperfect systems. In this article, we develop a more flexible class of pulse association models that incorporate parameters quantifying imperfect pulse associations. We propose a novel use of the Cox process model as a model of how pulse events co-occur in time. We embed the Cox process model into a hormone concentration model. Hormone concentration is the observed data. Spatial birth and death Markov chain Monte Carlo is used for estimation. Simulations show the joint model works well for quantifying both perfect and imperfect associations and offers estimation improvements over single hormone analyses. We apply this model to luteinizing hormone (LH) and follicle stimulating hormone (FSH), two reproductive hormones. Use of our joint model results in an ability to investigate novel hypotheses regarding associations between LH and FSH secretion in obese and non-obese women. © 2017, The International Biometric Society.

Precision spectroscopy of high rotational states in H2 investigated by Doppler-free two-photon laser spectroscopy in the EF 1Σg+-X 1Σg+ system

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Dickenson, G. D.; Salumbides, E. J.; Niu, M.; Jungen, Ch.; Ross, S. C.; Ubachs, W.

2012-09-01

Recently a high precision spectroscopic investigation of the EF1Σg+-X1Σg+ system of molecular hydrogen was reported yielding information on QED and relativistic effects in a sequence of rotational quantum states in the X1Σg+ ground state of the H2 molecule [Salumbides , Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.107.043005 107, 043005 (2011)]. The present paper presents a more detailed description of the methods and results. Furthermore, the paper serves as a stepping stone towards a continuation of the previous study by extending the known level structure of the EF1Σg+ state to highly excited rovibrational levels through Doppler-free two-photon spectroscopy. Based on combination differences between vibrational levels in the ground state, and between three rotational branches (O, Q, and S branches) assignments of excited EF1Σg+ levels, involving high vibrational and rotational quantum numbers, can be unambiguously made. For the higher EF1Σg+ levels, where no combination differences are available, calculations were performed using the multichannel quantum defect method, for a broad class of vibrational and rotational levels up to J=19. These predictions were used for assigning high-J EF levels and are found to be accurate within 5 cm-1.

Accounting for standard errors of vision-specific latent trait in regression models.

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Wong, Wan Ling; Li, Xiang; Li, Jialiang; Wong, Tien Yin; Cheng, Ching-Yu; Lamoureux, Ecosse L

2014-07-11

To demonstrate the effectiveness of Hierarchical Bayesian (HB) approach in a modeling framework for association effects that accounts for SEs of vision-specific latent traits assessed using Rasch analysis. A systematic literature review was conducted in four major ophthalmic journals to evaluate Rasch analysis performed on vision-specific instruments. The HB approach was used to synthesize the Rasch model and multiple linear regression model for the assessment of the association effects related to vision-specific latent traits. The effectiveness of this novel HB one-stage "joint-analysis" approach allows all model parameters to be estimated simultaneously and was compared with the frequently used two-stage "separate-analysis" approach in our simulation study (Rasch analysis followed by traditional statistical analyses without adjustment for SE of latent trait). Sixty-six reviewed articles performed evaluation and validation of vision-specific instruments using Rasch analysis, and 86.4% (n = 57) performed further statistical analyses on the Rasch-scaled data using traditional statistical methods; none took into consideration SEs of the estimated Rasch-scaled scores. The two models on real data differed for effect size estimations and the identification of "independent risk factors." Simulation results showed that our proposed HB one-stage "joint-analysis" approach produces greater accuracy (average of 5-fold decrease in bias) with comparable power and precision in estimation of associations when compared with the frequently used two-stage "separate-analysis" procedure despite accounting for greater uncertainty due to the latent trait. Patient-reported data, using Rasch analysis techniques, do not take into account the SE of latent trait in association analyses. The HB one-stage "joint-analysis" is a better approach, producing accurate effect size estimations and information about the independent association of exposure variables with vision-specific latent traits

Interactions between lower urinary tract symptoms and cardiovascular risk factors determine distinct patterns of erectile dysfunction: a latent class analysis.

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Barbosa, João A B A; Muracca, Eduardo; Nakano, Élcio; Assalin, Adriana R; Cordeiro, Paulo; Paranhos, Mario; Cury, José; Srougi, Miguel; Antunes, Alberto A

2013-12-01

An epidemiological association between lower urinary tract symptoms and erectile dysfunction is well established. However, interactions among multiple risk factors and the role of each in pathological mechanisms are not fully elucidated We enrolled 898 men undergoing prostate cancer screening for evaluation with the International Prostate Symptom Score (I-PSS) and simplified International Index of Erectile Function-5 (IIEF-5) questionnaires. Age, race, hypertension, diabetes, dyslipidemia, metabolic syndrome, cardiovascular disease, serum hormones and anthropometric parameters were also evaluated. Risk factors for erectile dysfunction were identified by logistic regression. The 333 men with at least mild to moderate erectile dysfunction (IIEF 16 or less) were included in a latent class model to identify relationships across erectile dysfunction risk factors. Age, hypertension, diabetes, lower urinary tract symptoms and cardiovascular event were independent predictors of erectile dysfunction (pclasses of patients with erectile dysfunction (R2 entropy=0.82). Latent class 1 had younger men at low cardiovascular risk and a moderate/high prevalence of lower urinary tract symptoms. Latent class 2 had the oldest patients at moderate cardiovascular risk with an increased prevalence of lower urinary tract symptoms. Latent class 3 had men of intermediate age with the highest prevalence of cardiovascular risk factors and lower urinary tract symptoms. Erectile dysfunction severity and lower urinary tract symptoms increased from latent class 1 to 3. Risk factor interactions determined different severities of lower urinary tract symptoms and erectile dysfunction. The effect of lower urinary tract symptoms and cardiovascular risk outweighed that of age. While in the youngest patients lower urinary tract symptoms acted as a single risk factor for erectile dysfunction, the contribution of vascular disease resulted in significantly more severe dysfunction. Applying a risk factor

Robust Measurement via A Fused Latent and Graphical Item Response Theory Model.

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Chen, Yunxiao; Li, Xiaoou; Liu, Jingchen; Ying, Zhiliang

2018-03-12

Item response theory (IRT) plays an important role in psychological and educational measurement. Unlike the classical testing theory, IRT models aggregate the item level information, yielding more accurate measurements. Most IRT models assume local independence, an assumption not likely to be satisfied in practice, especially when the number of items is large. Results in the literature and simulation studies in this paper reveal that misspecifying the local independence assumption may result in inaccurate measurements and differential item functioning. To provide more robust measurements, we propose an integrated approach by adding a graphical component to a multidimensional IRT model that can offset the effect of unknown local dependence. The new model contains a confirmatory latent variable component, which measures the targeted latent traits, and a graphical component, which captures the local dependence. An efficient proximal algorithm is proposed for the parameter estimation and structure learning of the local dependence. This approach can substantially improve the measurement, given no prior information on the local dependence structure. The model can be applied to measure both a unidimensional latent trait and multidimensional latent traits.

Dorsal bundle lesions do not affect latent inhibition of conditioned suppression.

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Tsaltas, E; Preston, G C; Rawlins, J N; Winocur, G; Gray, J A

1984-01-01

Three experiments are reported which examine the effects of lesions of the dorsal ascending noradrenergic bundle (DB) on latent inhibition using a conditioned suppression procedure in rats. In none of the experiments did the DB lesion have any effect, despite changes in the extent of latent inhibition and in the control procedures used to assess it. The results are discussed in relation to the attentional theory of DB function.

The MazEF Toxin-Antitoxin System Alters the β-Lactam Susceptibility of Staphylococcus aureus.

Directory of Open Access Journals (Sweden)

Christopher F Schuster

Full Text Available Toxin-antitoxin (TA systems are genetic elements of prokaryotes which encode a stable toxin and an unstable antitoxin that can counteract toxicity. TA systems residing on plasmids are often involved in episomal maintenance whereas those on chromosomes can have multiple functions. The opportunistic pathogen Staphylococcus aureus possesses at least four different families of TA systems but their physiological roles are elusive. The chromosomal mazEF system encodes the RNase toxin MazF and the antitoxin MazE. In the light of ambiguity regarding the cleavage activity, we here verify that MazF specifically targets UACAU sequences in S. aureus in vivo. In a native strain background and under non-stress conditions, cleavage was observed in the absence or presence of mazE. Transcripts of spa (staphylococcal protein A and rsbW (anti-σB factor were cut, but translational reporter fusions indicated that protein levels of the encoded products were unaffected. Despite a comparable growth rate as the wild-type, an S. aureus mazEF deletion mutant was more susceptible to β-lactam antibiotics, which suggests that further genes, putatively involved in the antibiotic stress response or cell wall synthesis or turnover, are controlled by this TA system.

Managing latent tuberculosis infection and tuberculosis in children

Directory of Open Access Journals (Sweden)

I. Carvalho

2018-03-01

Full Text Available Tuberculosis (TB is a major cause of childhood morbidity and mortality worldwide. The aim of this review is to describe the management of the child with TB and latent tuberculosis infection (LTBI.To develop this article, a working group reviewed relevant epidemiological and other scientific studies and established practices in conducting LBTI and TB in children. The article describes how to manage the child with LTBI, considering transmission and infectiousness of tuberculosis, contact screening and prioritization of contacts and recommendations on treatment of children with LTBI and how to manage the child with TB considering the susceptibility of children to developing tuberculosis, epidemiology and classification of tuberculosis in children, diagnosis and treatment. Keywords: Tuberculosis, Pediatric, Childhood, Latent tuberculosis infection

The Drosophila melanogaster Eip74EF-PA transcription factor directly binds the sciarid BhC4-1 promoter.

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Frank, Henrique Oliveira; Sanchez, Danilo Garcia; de Freitas Oliveira, Lucas; Kobarg, Jörg; Monesi, Nadia

2017-11-01

The DNA puff BhC4-1 gene of Bradysia hygida (Diptera, Sciaridae) is amplified and expressed in the salivary glands at the end of the last larval instar. Even though there are no BhC4-1 orthologs in Drosophila melanogaster, the mechanisms that regulate BhC4-1 gene expression in B. hygida are for the most part conserved in D. melanogaster. The BhC4-1 promoter contains a 129bp (-186/-58) cis-regulatory module (CRM) that drives developmentally regulated expression in transgenic salivary glands at the onset of metamorphosis. Both in the sciarid and in transgenic D. melanogaster, BhC4-1 gene expression is induced by the increase in ecdysone titers that triggers metamorphosis. Genetic interaction experiments revealed that in the absence of the Eip74EF-PA early gene isoform BhC4-1-lacZ levels of expression in the salivary gland are severely reduced. Here we show that the overexpression of the Eip74EF-PA transcription factor is sufficient to anticipate BhC4-1-lacZ expression in transgenic D. melanogaster. Through yeast one-hybrid assays we confirm that the Eip74EF-PA transcription factor directly binds to the 129 bp sciarid CRM. Together, these results contribute to the characterization of an insect CRM and indicate that the ecdysone gene regulatory network that promotes metamorphosis is conserved between D. melanogaster and the sciarid B. hygida. © 2017 Wiley Periodicals, Inc.

Latent memory facilitates relearning through molecular signaling mechanisms that are distinct from original learning.

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Menges, Steven A; Riepe, Joshua R; Philips, Gary T

2015-09-01

A highly conserved feature of memory is that it can exist in a latent, non-expressed state which is revealed during subsequent learning by its ability to significantly facilitate (savings) or inhibit (latent inhibition) subsequent memory formation. Despite the ubiquitous nature of latent memory, the mechanistic nature of the latent memory trace and its ability to influence subsequent learning remains unclear. The model organism Aplysia californica provides the unique opportunity to make strong links between behavior and underlying cellular and molecular mechanisms. Using Aplysia, we have studied the mechanisms of savings due to latent memory for a prior, forgotten experience. We previously reported savings in the induction of three distinct temporal domains of memory: short-term (10min), intermediate-term (2h) and long-term (24h). Here we report that savings memory formation utilizes molecular signaling pathways that are distinct from original learning: whereas the induction of both original intermediate- and long-term memory in naïve animals requires mitogen activated protein kinase (MAPK) activation and ongoing protein synthesis, 2h savings memory is not disrupted by inhibitors of MAPK or protein synthesis, and 24h savings memory is not dependent on MAPK activation. Collectively, these findings reveal that during forgetting, latent memory for the original experience can facilitate relearning through molecular signaling mechanisms that are distinct from original learning. Copyright © 2015 Elsevier Inc. All rights reserved.

Statistical inference based on latent ability estimates

NARCIS (Netherlands)

Hoijtink, H.J.A.; Boomsma, A.

The quality of approximations to first and second order moments (e.g., statistics like means, variances, regression coefficients) based on latent ability estimates is being discussed. The ability estimates are obtained using either the Rasch, oi the two-parameter logistic model. Straightforward use

Variable importance in latent variable regression models

NARCIS (Netherlands)

Kvalheim, O.M.; Arneberg, R.; Bleie, O.; Rajalahti, T.; Smilde, A.K.; Westerhuis, J.A.

2014-01-01

The quality and practical usefulness of a regression model are a function of both interpretability and prediction performance. This work presents some new graphical tools for improved interpretation of latent variable regression models that can also assist in improved algorithms for variable

Space-time latent component modeling of geo-referenced health data.

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Lawson, Andrew B; Song, Hae-Ryoung; Cai, Bo; Hossain, Md Monir; Huang, Kun

2010-08-30

Latent structure models have been proposed in many applications. For space-time health data it is often important to be able to find the underlying trends in time, which are supported by subsets of small areas. Latent structure modeling is one such approach to this analysis. This paper presents a mixture-based approach that can be applied to component selection. The analysis of a Georgia ambulatory asthma county-level data set is presented and a simulation-based evaluation is made. Copyright (c) 2010 John Wiley & Sons, Ltd.

Heterogeneity of executive functions among comorbid neurodevelopmental disorders

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Dajani, Dina R.; Llabre, Maria M.; Nebel, Mary Beth; Mostofsky, Stewart H.; Uddin, Lucina Q.

2016-01-01

Executive functions (EFs) are used to set goals, plan for the future, inhibit maladaptive responses, and change behavior flexibly. Although some studies point to specific EF profiles in autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) — prevalent and often highly comorbid neurodevelopmental disorders — others have not differentiated them. The objective of the current study was to identify distinct profiles of EF across typically developing (TD) children and children with ASD and ADHD. We employed a latent profile analysis using indicators of EF (e.g., working memory, inhibition, and flexibility) in a mixed group of 8–13 year-olds including TD children (n = 128), children with ASD without ADHD (n = 30), children with ADHD (n = 93), and children with comorbid ASD and ADHD (n = 66). Three EF classes emerged: “above average,” “average,” and “impaired.” EF classes did not reproduce diagnostic categories, suggesting that differences in EF abilities are present within the ASD and ADHD groups. Further, greater EF dysfunction predicted more severe socioemotional problems, such as anxiety/depression. These results highlight the heterogeneity of current diagnostic groups and identify an “impaired” EF group, consisting of children with both ASD and ADHD, which could specifically be targeted for EF intervention. PMID:27827406

Confidence Intervals for a Semiparametric Approach to Modeling Nonlinear Relations among Latent Variables

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Pek, Jolynn; Losardo, Diane; Bauer, Daniel J.

2011-01-01

Compared to parametric models, nonparametric and semiparametric approaches to modeling nonlinearity between latent variables have the advantage of recovering global relationships of unknown functional form. Bauer (2005) proposed an indirect application of finite mixtures of structural equation models where latent components are estimated in the…

Barcelona - Talent Latent 09 / Ahto Sooaru

Index Scriptorium Estoniae

Sooaru, Ahto

2010-01-01

Fotonäitusest "Talent Latent 09" Barcelonas Arts Santa Monica kunstikeskuses. Loetletud näitusel eksponeeritud fotode autorid. Pikemalt Rafael Milach'i (sünd. 1978), Lucia Ganieva, Javier Marquerie Thomas'i (sünd. 1986), Amaury da Cunha (sünd. 1976) töödest. Lühidalt ka teistest näitustest Arts Santa Monica kunstikeskuses

Transcriptional Regulation of Latent Feline Immunodeficiency Virus in Peripheral CD4+ T-lymphocytes

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Brian G. Murphy

2012-05-01

Full Text Available Feline immunodeficiency virus (FIV, the lentivirus of domestic cats responsible for feline AIDS, establishes a latent infection in peripheral blood CD4+ T-cells approximately eight months after experimental inoculation. In this study, cats experimentally infected with the FIV-C strain in the asymptomatic phase demonstrated an estimated viral load of 1 infected cell per approximately 10³ CD4+ T-cells, with about 1 copy of viral DNA per cell. Approximately 1 in 10 proviral copies was capable of transcription in the asymptomatic phase. The latent FIV proviral promoter was associated with deacetylated, methylated histones, which is consistent with a condensed chromatin structure. In contrast, the transcriptionally active FIV promoter was associated with histone acetylation and demethylation. In addition, RNA polymerase II appeared to be paused on the latent viral promoter, and short promoter-proximal transcripts were detected. Our findings for the FIV promoter in infected cats are similar to results obtained in studies of human immunodeficiency virus (HIV-1 latent proviruses in cell culture in vitro studies. Thus, the FIV/cat model may offer insights into in vivo mechanisms of HIV latency and provides a unique opportunity to test novel therapeutic interventions aimed at eradicating latent virus.

Estimating Non-Normal Latent Trait Distributions within Item Response Theory Using True and Estimated Item Parameters

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Sass, D. A.; Schmitt, T. A.; Walker, C. M.

2008-01-01

Item response theory (IRT) procedures have been used extensively to study normal latent trait distributions and have been shown to perform well; however, less is known concerning the performance of IRT with non-normal latent trait distributions. This study investigated the degree of latent trait estimation error under normal and non-normal…

Treatment of Latent Tuberculosis Infection

OpenAIRE

Tang, Patrick; Johnston, James

2017-01-01

Opinion statement The treatment of latent tuberculosis infection (LTBI) is an essential component of tuberculosis (TB) elimination in regions that have a low incidence of TB. However, the decision to treat individuals with LTBI must consider the limitations of current diagnostic tests for LTBI, the risk of developing active TB disease, the potential adverse effects from chemoprophylactic therapy, and the importance of treatment adherence. When an individual has been diagnosed with LTBI and ac...

The latent structure of oppositional defiant disorder in children and adults.

Science.gov (United States)

Barry, Tammy D; Marcus, David K; Barry, Christopher T; Coccaro, Emil F

2013-12-01

An understanding of the latent structure of oppositional defiant disorder (ODD) is essential for better developing causal models, improving diagnostic and assessment procedures, and enhancing treatments for the disorder. Although much research has focused on ODD-including recent studies informing the diagnostic criteria for DSM-5-research examining the latent structure of ODD is sparse, and no known study has specifically undertaken a taxometric analysis to address the issue of whether ODD is a categorical or dimensional construct. To address this gap, the authors conducted two separate studies using a set of taxometric analyses with data from the NICHD Study of Early Child Care and Youth Development (child study; n = 969) and with data from a large mixed sample of adults, which included participants reporting psychiatric difficulties as well as healthy controls (adult study; n = 600). The results of a variety of non-redundant analyses across both studies revealed a dimensional latent structure for ODD symptoms among both children and adults. These findings are consistent with previous studies that have examined latent structure of related constructs (e.g., aggression, antisocial behavior) as well as studies that have examined the dimensional versus categorical structure of ODD using methods other than taxometric analysis. Copyright © 2013 Elsevier Ltd. All rights reserved.

Building latent class trees, with an application to a study of social capital

NARCIS (Netherlands)

van den Bergh, M.; Schmittmann, V.D.; Vermunt, J.K.

2017-01-01

Researchers use latent class (LC) analysis to derive meaningful clusters from sets of categorical variables. However, especially when the number of classes required to obtain a good fit is large, interpretation of the latent classes may not be straightforward. To overcome this problem, we propose an

Cross-Informant Agreement on Child and Adolescent Withdrawn Behavior: A Latent Class Approach

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Rubin, David H.; Althoff, Robert R.; Walkup, John T.; Hudziak, James J.

2013-01-01

Withdrawn behavior (WB) relates to many developmental outcomes, including pervasive developmental disorders, anxiety, depression, psychosis, personality disorders and suicide. No study has compared the latent profiles of different informants' reports on WB. This study uses multi-informant latent class analyses (LCA) of the child behavior checklist…

The utrophin A 5'-UTR drives cap-independent translation exclusively in skeletal muscles of transgenic mice and interacts with eEF1A2.

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Miura, P; Coriati, A; Bélanger, G; De Repentigny, Y; Lee, J; Kothary, R; Holcik, M; Jasmin, B J

2010-04-01

The molecular mechanisms regulating expression of utrophin A are of therapeutic interest since upregulating its expression at the sarcolemma can compensate for the lack of dystrophin in animal models of Duchenne Muscular Dystrophy (DMD). The 5'-UTR of utrophin A has been previously shown to drive cap-independent internal ribosome entry site (IRES)-mediated translation in response to muscle regeneration and glucocorticoid treatment. To determine whether the utrophin A IRES displays tissue specific activity, we generated transgenic mice harboring control (CMV/betaGAL/CAT) or utrophin A 5'-UTR (CMV/betaGAL/UtrA/CAT) bicistronic reporter transgenes. Examination of multiple tissues from two CMV/betaGAL/UtrA/CAT lines revealed that the utrophin A 5'-UTR drives cap-independent translation of the reporter gene exclusively in skeletal muscles and no other examined tissues. This expression pattern suggested that skeletal muscle-specific factors are involved in IRES-mediated translation of utrophin A. We performed RNA-affinity chromatography experiments combined with mass spectrometry to identify trans-factors that bind the utrophin A 5'-UTR and identified eukaryotic elongation factor 1A2 (eEF1A2). UV-crosslinking experiments confirmed the specificity of this interaction. Regions of the utrophin A 5'-UTR that bound eEF1A2 also mediated cap-independent translation in C2C12 muscle cells. Cultured cells lacking eEF1A2 had reduced IRES activity compared with cells overexpressing eEF1A2. Together, these results suggest an important role for eEF1A2 in driving cap-independent translation of utrophin A in skeletal muscle. The trans-factors and signaling pathways driving skeletal-muscle specific IRES-mediated translation of utrophin A could provide unique targets for developing pharmacological-based DMD therapies.

Discriminative latent models for recognizing contextual group activities.

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Lan, Tian; Wang, Yang; Yang, Weilong; Robinovitch, Stephen N; Mori, Greg

2012-08-01

In this paper, we go beyond recognizing the actions of individuals and focus on group activities. This is motivated from the observation that human actions are rarely performed in isolation; the contextual information of what other people in the scene are doing provides a useful cue for understanding high-level activities. We propose a novel framework for recognizing group activities which jointly captures the group activity, the individual person actions, and the interactions among them. Two types of contextual information, group-person interaction and person-person interaction, are explored in a latent variable framework. In particular, we propose three different approaches to model the person-person interaction. One approach is to explore the structures of person-person interaction. Differently from most of the previous latent structured models, which assume a predefined structure for the hidden layer, e.g., a tree structure, we treat the structure of the hidden layer as a latent variable and implicitly infer it during learning and inference. The second approach explores person-person interaction in the feature level. We introduce a new feature representation called the action context (AC) descriptor. The AC descriptor encodes information about not only the action of an individual person in the video, but also the behavior of other people nearby. The third approach combines the above two. Our experimental results demonstrate the benefit of using contextual information for disambiguating group activities.

Residual Structures in Latent Growth Curve Modeling

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Grimm, Kevin J.; Widaman, Keith F.

2010-01-01

Several alternatives are available for specifying the residual structure in latent growth curve modeling. Two specifications involve uncorrelated residuals and represent the most commonly used residual structures. The first, building on repeated measures analysis of variance and common specifications in multilevel models, forces residual variances…

An in-depth comparison of latent HIV-1 reactivation in multiple cell model systems and resting CD4+ T cells from aviremic patients.

Directory of Open Access Journals (Sweden)

Celsa A Spina

Full Text Available The possibility of HIV-1 eradication has been limited by the existence of latently infected cellular reservoirs. Studies to examine control of HIV latency and potential reactivation have been hindered by the small numbers of latently infected cells found in vivo. Major conceptual leaps have been facilitated by the use of latently infected T cell lines and primary cells. However, notable differences exist among cell model systems. Furthermore, screening efforts in specific cell models have identified drug candidates for "anti-latency" therapy, which often fail to reactivate HIV uniformly across different models. Therefore, the activity of a given drug candidate, demonstrated in a particular cellular model, cannot reliably predict its activity in other cell model systems or in infected patient cells, tested ex vivo. This situation represents a critical knowledge gap that adversely affects our ability to identify promising treatment compounds and hinders the advancement of drug testing into relevant animal models and clinical trials. To begin to understand the biological characteristics that are inherent to each HIV-1 latency model, we compared the response properties of five primary T cell models, four J-Lat cell models and those obtained with a viral outgrowth assay using patient-derived infected cells. A panel of thirteen stimuli that are known to reactivate HIV by defined mechanisms of action was selected and tested in parallel in all models. Our results indicate that no single in vitro cell model alone is able to capture accurately the ex vivo response characteristics of latently infected T cells from patients. Most cell models demonstrated that sensitivity to HIV reactivation was skewed toward or against specific drug classes. Protein kinase C agonists and PHA reactivated latent HIV uniformly across models, although drugs in most other classes did not.

An In-Depth Comparison of Latent HIV-1 Reactivation in Multiple Cell Model Systems and Resting CD4+ T Cells from Aviremic Patients

Science.gov (United States)

Spina, Celsa A.; Anderson, Jenny; Archin, Nancie M.; Bosque, Alberto; Chan, Jonathan; Famiglietti, Marylinda; Greene, Warner C.; Kashuba, Angela; Lewin, Sharon R.; Margolis, David M.; Mau, Matthew; Ruelas, Debbie; Saleh, Suha; Shirakawa, Kotaro; Siliciano, Robert F.; Singhania, Akul; Soto, Paula C.; Terry, Valeri H.; Verdin, Eric; Woelk, Christopher; Wooden, Stacey; Xing, Sifei; Planelles, Vicente

2013-01-01

The possibility of HIV-1 eradication has been limited by the existence of latently infected cellular reservoirs. Studies to examine control of HIV latency and potential reactivation have been hindered by the small numbers of latently infected cells found in vivo. Major conceptual leaps have been facilitated by the use of latently infected T cell lines and primary cells. However, notable differences exist among cell model systems. Furthermore, screening efforts in specific cell models have identified drug candidates for “anti-latency” therapy, which often fail to reactivate HIV uniformly across different models. Therefore, the activity of a given drug candidate, demonstrated in a particular cellular model, cannot reliably predict its activity in other cell model systems or in infected patient cells, tested ex vivo. This situation represents a critical knowledge gap that adversely affects our ability to identify promising treatment compounds and hinders the advancement of drug testing into relevant animal models and clinical trials. To begin to understand the biological characteristics that are inherent to each HIV-1 latency model, we compared the response properties of five primary T cell models, four J-Lat cell models and those obtained with a viral outgrowth assay using patient-derived infected cells. A panel of thirteen stimuli that are known to reactivate HIV by defined mechanisms of action was selected and tested in parallel in all models. Our results indicate that no single in vitro cell model alone is able to capture accurately the ex vivo response characteristics of latently infected T cells from patients. Most cell models demonstrated that sensitivity to HIV reactivation was skewed toward or against specific drug classes. Protein kinase C agonists and PHA reactivated latent HIV uniformly across models, although drugs in most other classes did not. PMID:24385908

A Medicago truncatula EF-hand family gene, MtCaMP1, is involved in drought and salt stress tolerance.

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Tian-Zuo Wang

Full Text Available BACKGROUND: Calcium-binding proteins that contain EF-hand motifs have been reported to play important roles in transduction of signals associated with biotic and abiotic stresses. To functionally characterize genes of EF-hand family in response to abiotic stress, an MtCaMP1 gene belonging to EF-hand family from legume model plant Medicago truncatula was isolated and its function in response to drought and salt stress was investigated by expressing MtCaMP1 in Arabidopsis. METHODOLOGY/PRINCIPAL FINDINGS: Transgenic Arabidopsis seedlings expressing MtCaMP1 exhibited higher survival rate than wild-type seedlings under drought and salt stress, suggesting that expression of MtCaMP1 confers tolerance of Arabidopsis to drought and salt stress. The transgenic plants accumulated greater amounts of Pro due to up-regulation of P5CS1 and down-regulation of ProDH than wild-type plants under drought stress. There was a less accumulation of Na(+ in the transgenic plants than in WT plants due to reduced up-regulation of AtHKT1 and enhanced regulation of AtNHX1 in the transgenic plants compared to WT plants under salt stress. There was a reduced accumulation of H2O2 and malondialdehyde in the transgenic plants than in WT plants under both drought and salt stress. CONCLUSIONS/SIGNIFICANCE: The expression of MtCaMP1 in Arabidopsis enhanced tolerance of the transgenic plants to drought and salt stress by effective osmo-regulation due to greater accumulation of Pro and by minimizing toxic Na(+ accumulation, respectively. The enhanced accumulation of Pro and reduced accumulation of Na(+ under drought and salt stress would protect plants from water default and Na(+ toxicity, and alleviate the associated oxidative stress. These findings demonstrate that MtCaMP1 encodes a stress-responsive EF-hand protein that plays a regulatory role in response of plants to drought and salt stress.

Discovery of optical flickering from the symbiotic star EF Aquilae

Science.gov (United States)

Zamanov, R. K.; Boeva, S.; Nikolov, Y. M.; Petrov, B.; Bachev, R.; Latev, G. Y.; Popov, V. A.; Stoyanov, K. A.; Bode, M. F.; Martí, J.; Tomov, T.; Antonova, A.

2017-07-01

We report optical CCD photometry of the recently identified symbiotic star EF Aql. Our observations in Johnson V and B bands clearly show the presence of stochastic light variations with an amplitude of about 0.2 mag on a time scale of minutes. The observations point toward a white dwarf (WD) as the hot component in the system. It is the 11-th object among more than 200 symbiotic stars known with detected optical flickering. Estimates of the mass accretion rate onto the WD and the mass loss rate in the wind of the Mira secondary star lead to the conclusion that less than 1 per cent of the wind is captured by the WD. Eight further candidates for the detection of flickering in similar systems are suggested.

Pneumonia cases following an EF-5 tornado.

Science.gov (United States)

Forshee-Hakala, Beth A

2015-07-01

Infections following a natural disaster such as an EF-5 tornado can be atypical and difficult to treat. Studies have looked at illness following several natural disasters, but few have studied respiratory illness following a tornado. A review of patients with pneumonia admitted during the period from May 22, 2009, through May 21, 2012, was completed. The Tornado Zone Group included adult patients who lived or worked in the tornado zone during the year following the tornado. Data were isolated by number of pneumonia cases within and outside the tornado zone per month per year. An analysis of variance comparing the number of pneumonia cases from the tornado zone per month per year was significant at F2,38 = 12.93 and P Tornado Zone Group (P Tornado Zone patients to be younger than controls (t390 = 5.14; P Tornado Zone Group included uncommon pathogens not isolated during the 2 years prior. The number of pneumonia cases may increase following tornadoes. Although current guidelines recommend narrow-spectrum antibiotics for community-acquired pneumonia, results of this study suggest the possible need for broader antimicrobial coverage after tornadoes. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

A Model for the Sounding Rocket Measurement on an Ionospheric E-F Valley at the Hainan Low Latitude Station

International Nuclear Information System (INIS)

Wang Zheng; Shi Jiankui; Guan Yibing; Liu Chao; Zhu Guangwu; Torkar Klaus; Fredrich Martin

2014-01-01

To understand the physics of an ionospheric E-F valley, a new overlapping three-Chapman-layer model is developed to interpret the sounding rocket measurement in the morning (sunrise) on May 7, 2011 at the Hainan low latitude ionospheric observation station (19.5°N, 109.1°E). From our model, the valley width, depth and height are 43.0 km, 62.9% and 121.0 km, respectively. From the sounding rocket observation, the valley width, depth and height are 42.2 km, 47.0% and 123.5 km, respectively. The model results are well consistent with the sounding rocket observation. The observed E-F valley at Hainan station is very wide and deep, and rapid development of the photochemical process in the ionosphere should be the underlying reason. (astrophysics and space plasma)

Bayesian modeling of ChIP-chip data using latent variables.

KAUST Repository

Wu, Mingqi

2009-10-26

BACKGROUND: The ChIP-chip technology has been used in a wide range of biomedical studies, such as identification of human transcription factor binding sites, investigation of DNA methylation, and investigation of histone modifications in animals and plants. Various methods have been proposed in the literature for analyzing the ChIP-chip data, such as the sliding window methods, the hidden Markov model-based methods, and Bayesian methods. Although, due to the integrated consideration of uncertainty of the models and model parameters, Bayesian methods can potentially work better than the other two classes of methods, the existing Bayesian methods do not perform satisfactorily. They usually require multiple replicates or some extra experimental information to parametrize the model, and long CPU time due to involving of MCMC simulations. RESULTS: In this paper, we propose a Bayesian latent model for the ChIP-chip data. The new model mainly differs from the existing Bayesian models, such as the joint deconvolution model, the hierarchical gamma mixture model, and the Bayesian hierarchical model, in two respects. Firstly, it works on the difference between the averaged treatment and control samples. This enables the use of a simple model for the data, which avoids the probe-specific effect and the sample (control/treatment) effect. As a consequence, this enables an efficient MCMC simulation of the posterior distribution of the model, and also makes the model more robust to the outliers. Secondly, it models the neighboring dependence of probes by introducing a latent indicator vector. A truncated Poisson prior distribution is assumed for the latent indicator variable, with the rationale being justified at length. CONCLUSION: The Bayesian latent method is successfully applied to real and ten simulated datasets, with comparisons with some of the existing Bayesian methods, hidden Markov model methods, and sliding window methods. The numerical results indicate that the

Effector region of the translation elongation factor EF-Tu.GTP complex stabilizes an orthoester acid intermediate structure of aminoacyl-tRNA in a ternary complex.

Science.gov (United States)

Förster, C; Limmer, S; Zeidler, W; Sprinzl, M

1994-01-01

tRNA(Val) from Escherichia coli was aminoacylated with [1-13C]valine and its complex with Thermus thermophilus elongation factor EF-Tu.GTP was analyzed by 13C NMR spectroscopy. The results suggest that the aminoacyl residue of the valyl-tRNA in ternary complex with bacterial EF-Tu and GTP is not attached to tRNA by a regular ester bond to either a 2'- or 3'-hydroxyl group; instead, an intermediate orthoester acid structure with covalent linkage to both vicinal hydroxyls of the terminal adenosine-76 is formed. Mutation of arginine-59 located in the effector region of EF-Tu, a conserved residue in protein elongation factors and the alpha subunits of heterotrimeric guanine nucleotide-binding regulatory proteins (G proteins), abolishes the stabilization of the orthoester acid structure of aminoacyl-tRNA. PMID:8183898

Homeostatic proliferation fails to efficiently reactivate HIV-1 latently infected central memory CD4+ T cells.

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Alberto Bosque

2011-10-01

Full Text Available Homeostatic proliferation ensures the longevity of central memory T-cells by inducing cell proliferation in the absence of cellular differentiation or activation. This process is governed mainly by IL-7. Central memory T-cells can also be stimulated via engagement of the T-cell receptor, leading to cell proliferation but also activation and differentiation. Using an in vitro model of HIV-1 latency, we have examined in detail the effects of homeostatic proliferation on latently infected central memory T cells. We have also used antigenic stimulation via anti-CD3/anti-CD28 antibodies and established a comparison with a homeostatic proliferation stimulus, to evaluate potential differences in how either treatment affects the dynamics of latent virus populations. First, we show that homeostatic proliferation, as induced by a combination of IL-2 plus IL-7, leads to partial reactivation of latent HIV-1 but is unable to reduce the size of the reservoir in vitro. Second, latently infected cells are able to homeostatically proliferate in the absence of viral reactivation or cell differentiation. These results indicate that IL-2 plus IL-7 may induce a detrimental effect by favoring the maintenance of the latent HIV-1 reservoir. On the other hand, antigenic stimulation efficiently reactivated latent HIV-1 in cultured central memory cells and led to depletion of the latently infected cells via virus-induced cell death.

Substantiation for Approaches to Treatment of Latent Autoimmune Diabetes in Adults

Directory of Open Access Journals (Sweden)

T.M. Tykhonova

2014-10-01

Conclusions. Analysis of carbohydrate metabolism on the manifestation stage and over time development of latent autoimmune diabetes in adults as well as reduction of β-cells insulin-producing function associated with autoimmune insulitis and progressing while the development of this form of disease, substantiate the rational for insulin administration as this form of diabetes has been diagnosed. If patients with latent autoimmune diabetes in adults have metabolic syndrome clusters it is quite reasonable to add metformin to insulin.

Extra Heat Loss Through Light Weight Roofs Due to Latent Heat

DEFF Research Database (Denmark)

Rode, Carsten

1996-01-01

that changes phase at the terminals of its passage.Note however, that convection of air most often will have an important effect on the overall heat flow - but that is a different topic.Macroscopic latent heat transferConsider the following scenario: Initially, moisture is present in its condensed or frozen......This report is one in a series of papers in Task 5 of IEA Annex 24 on how moisture and air movements affect the energy performance of building constructions. The effect of latent heat flow will be demonstrated by means of an example: a light weight flat roof.Latent heat flow is one of three...... processes by which moisture affects energy performance:Higher thermal conductivityMoist materials have higher thermal con-ductivity than when they are dry. This is because thermally conducting moisture replaces the better insulating air in the pores of the materials. Moisture also enhan-ces the thermal...

Do gender and directness of trauma exposure moderate PTSD's latent structure?

Science.gov (United States)

Frankfurt, Sheila B; Armour, Cherie; Contractor, Ateka A; Elhai, Jon D

2016-11-30

The PTSD diagnosis and latent structure were substantially revised in the transition from DSM-IV to DSM-5. However, three alternative models (i.e., anhedonia model, externalizing behavior model, and hybrid model) of PTSD fit the DSM-5 symptom criteria better than the DSM-5 factor model. Thus, the psychometric performance of the DSM-5 and alternative models' PTSD factor structure needs to be critically evaluated. The current study examined whether gender or trauma directness (i.e., direct or indirect trauma exposure) moderates the PTSD latent structure when using the DSM-5 or alternative models. Model performance was evaluated with measurement invariance testing procedures on a large undergraduate sample (n=455). Gender and trauma directness moderated the DSM-5 PTSD and externalizing behavior model and did not moderate the anhedonia and hybrid models' latent structure. Clinical implications and directions for future research are discussed. Published by Elsevier Ireland Ltd.

Pre-clinical cognitive phenotypes for Alzheimer disease: a latent profile approach.

Science.gov (United States)

Hayden, Kathleen M; Kuchibhatla, Maragatha; Romero, Heather R; Plassman, Brenda L; Burke, James R; Browndyke, Jeffrey N; Welsh-Bohmer, Kathleen A

2014-11-01

Cognitive profiles for pre-clinical Alzheimer disease (AD) can be used to identify groups of individuals at risk for disease and better characterize pre-clinical disease. Profiles or patterns of performance as pre-clinical phenotypes may be more useful than individual test scores or measures of global decline. To evaluate patterns of cognitive performance in cognitively normal individuals to derive latent profiles associated with later onset of disease using a combination of factor analysis and latent profile analysis. The National Alzheimer Coordinating Centers collect data, including a battery of neuropsychological tests, from participants at 29 National Institute on Aging-funded Alzheimer Disease Centers across the United States. Prior factor analyses of this battery demonstrated a four-factor structure comprising memory, attention, language, and executive function. Factor scores from these analyses were used in a latent profile approach to characterize cognition among a group of cognitively normal participants (N = 3,911). Associations between latent profiles and disease outcomes an average of 3 years later were evaluated with multinomial regression models. Similar analyses were used to determine predictors of profile membership. Four groups were identified; each with distinct characteristics and significantly associated with later disease outcomes. Two groups were significantly associated with development of cognitive impairment. In post hoc analyses, both the Trail Making Test Part B, and a contrast score (Delayed Recall - Trails B), significantly predicted group membership and later cognitive impairment. Latent profile analysis is a useful method to evaluate patterns of cognition in large samples for the identification of preclinical AD phenotypes; comparable results, however, can be achieved with very sensitive tests and contrast scores. Copyright © 2014 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

Sensible and latent heat forced divergent circulations in the West African Monsoon System

Science.gov (United States)

Hagos, S.; Zhang, C.

2008-12-01

Field properties of divergent circulation are utilized to identify the roles of various diabatic processes in forcing moisture transport in the dynamics of the West African Monsoon and its seasonal cycle. In this analysis, the divergence field is treated as a set of point sources and is partitioned into two sub-sets corresponding to latent heat release and surface sensible heat flux at each respective point. The divergent circulation associated with each set is then calculated from the Poisson's equation using Gauss-Seidel iteration. Moisture transport by each set of divergent circulation is subsequently estimated. The results show different roles of the divergent circulations forced by surface sensible and latent heating in the monsoon dynamics. Surface sensible heating drives a shallow meridional circulation, which transports moisture deep into the continent at the polar side of the monsoon rain band and thereby promotes the seasonal northward migration of monsoon precipitation during the monsoon onset season. In contrast, the circulation directly associated with latent heating is deep and the corresponding moisture convergence is within the region of precipitation. Latent heating also induces dry air advection from the north. Neither effect promotes the seasonal northward migration of precipitation. The relative contributions of the processes associated with latent and sensible heating to the net moisture convergence, and hence the seasonal evolution of monsoon precipitation, depend on the background moisture.

Some children with autism have latent social skills that can be tested

Czech Academy of Sciences Publication Activity Database

Hrdlička, M.; Urbánek, Tomáš; Vacová, M.; Beranová, Š.; Dudová, I.

2017-01-01

Roč. 13, March (2017), s. 827-833 ISSN 1178-2021 Institutional support: RVO:68081740 Keywords : autism * latent social skills * Autism Diagnostic Interview – Revised * Autism Diagnostic Observation Schedule * prediction Subject RIV: AN - Psychology OBOR OECD: Psychology (including human - machine relations) Impact factor: 2.198, year: 2016 https://www.dovepress.com/some-children-with- autism -have-latent-social-skills-that-can-be-tested-peer-reviewed-article-NDT

Some children with autism have latent social skills that can be tested

Czech Academy of Sciences Publication Activity Database

Hrdlička, M.; Urbánek, Tomáš; Vacová, M.; Beranová, Š.; Dudová, I.

2017-01-01

Roč. 13, March (2017), s. 827-833 ISSN 1178-2021 Institutional support: RVO:68081740 Keywords : autism * latent social skills * Autism Diagnostic Interview – Revised * Autism Diagnostic Observation Schedule * prediction Subject RIV: AN - Psychology OBOR OECD: Psychology (including human - machine relations) Impact factor: 2.198, year: 2016 https://www.dovepress.com/some-children-with-autism-have-latent- social -skills-that-can-be-tested-peer-reviewed-article-NDT

Anaerobic expression of the gadE-mdtEF multidrug efflux operon is primarily regulated by the two-component system ArcBA through antagonizing the H-NS mediated repression.

Science.gov (United States)

Deng, Ziqing; Shan, Yue; Pan, Qing; Gao, Xiang; Yan, Aixin

2013-01-01

The gadE-mdtEF operon encodes a central acid resistance regulator GadE and two multidrug efflux proteins MdtEF. Although transcriptional regulation of gadE in the context of acid resistance under the aerobic growth environment of Escherichia coli has been extensively studied, regulation of the operon under the physiologically relevant environment of anaerobic growth and its effect on the expression of the multidrug efflux proteins MdtEF in the operon has not been disclosed. Our previous study revealed that anaerobic induction of the operon was dependent on ArcA, the response regulator of the ArcBA two-component system, in the M9 glucose minimal medium. However, the detailed regulatory mechanism remains unknown. In this study, we showed that anaerobic activation of mdtEF was driven by the 798 bp unusually long gadE promoter. Deletion of evgA, ydeO, rpoS, and gadX which has been shown to activate the gadE expression during acid stresses under aerobic condition did not have a significant effect on the anaerobic activation of the operon. Rather, anaerobic activation of the operon was largely dependent on the global regulator ArcA and a GTPase MnmE. Under aerobic condition, transcription of gadE was repressed by the global DNA silencer H-NS in M9 minimal medium. Interestingly, under anaerobic condition, while ΔarcA almost completely abolished transcription of gadE-mdtEF, further deletion of hns in ΔarcA mutant restored the transcription of the full-length PgadE-lacZ, and P1- and P3-lacZ fusions, suggesting an antagonistic effect of ArcA on the H-NS mediated repression. Taken together, we conclude that the anaerobic activation of the gadE-mdtEF was primarily mediated by the two-component system ArcBA through antagonizing the H-NS mediated repression.

Anaerobic expression of the gadE-mdtEF multidrug efflux operon is primarily regulated by the two-component system ArcBA through antagonizing the H-NS mediated repression

Directory of Open Access Journals (Sweden)

Ziqing eDeng

2013-07-01

Full Text Available The gadE-mdtEF operon encodes a central acid resistance regulator GadE and two multidrug efflux proteins MdtEF. Although transcriptional regulation of gadE in the context of acid resistance under the aerobic growth environment of E. coli has been extensively studied, regulation of the operon under the physiologically relevant environment of anaerobic growth and its effect on the expression of the multidrug efflux proteins MdtEF has not been disclosed. Our previous study revealed that anaerobic induction of the operon was dependent on ArcA, the response regulator of the ArcBA two-component system, in the M9 glucose minimal medium. However, the detailed regulatory mechanism remains unknown. In this study, we showed that anaerobic activation of mdtEF was driven by the 798bp unusually long gadE promoter. Deletion of evgA, ydeO, rpoS, and gadX which has been shown to activate the gadE expression during acid stresses under aerobic condition did not have a significant effect on the anaerobic activation of the operon. Rather, anaerobic activation of the operon was largely dependent on the global regulator ArcA and a GTPase MnmE. Under aerobic condition, transcription of gadE was repressed by the global DNA silencer H-NS in M9 minimal medium. Interestingly, under anaerobic condition, while ΔarcA almost completely abolished transcription of gadE-mdtEF, further deletion of hns in ΔarcA mutant restored the transcription of the full length PgadE-lacZ, and P1- and P3-lacZ fusions, suggesting an antagonistic effect of ArcA on the H-NS mediated repression. Taken together, we conclude that the anaerobic activation of the gadE-mdtEF was primarily mediated by the two-component system ArcBA through antagonizing the H-NS mediated repression.

Influence of WFIKKN1 on BMP1-mediated activation of latent myostatin.

Science.gov (United States)

Szláma, György; Vásárhelyi, Viktor; Trexler, Mária; Patthy, László

2016-12-01

The NTR domain of WFIKKN1 protein has been shown to have significant affinity for the prodomain regions of promyostatin and latent myostatin but the biological significance of these interactions remained unclear. In view of its role as a myostatin antagonist, we tested the assumption that WFIKKN1 inhibits the release of myostatin from promyostatin and/or latent myostatin. WFIKKN1 was found to have no effect on processing of promyostatin by furin, the rate of cleavage of latent myostatin by BMP1, however, was significantly enhanced in the presence of WFIKKN1 and this enhancer activity was superstimulated by heparin. Unexpectedly, WFIKKN1 was also cleaved by BMP1 and our studies have shown that the KKN1 fragment generated by BMP1-cleavage of WFIKKN1 contributes most significantly to the observed enhancer activity. Analysis of a pro-TGF-β -based homology model of homodimeric latent myostatin revealed that the BMP1-cleavage sites are buried and not readily accessible to BMP1. In view of this observation, the most plausible explanation for the BMP1-enhancer activity of the KKN1 fragment is that it shifts a conformational equilibrium of latent myostatin from the closed circular structure of the homodimer to a more open form, making the cleavage sites more accessible to BMP1. On the other hand, the observation that the enhancer activity of KKN1 is superstimulated in the presence of heparin is explained by the fact KKN1, latent myostatin, and BMP1 have affinity for heparin and these interactions with heparin increase the local concentrations of the reactants thereby facilitating the action of BMP1. Furin: EC 3.4.21.75; BMP1, bone morphogentic protein 1 or procollagen C-endopeptidase: EC 3.4.24.19. © 2016 The Authors. The FEBS Journal published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.

Latent factor structure of a behavioral economic marijuana demand curve.

Science.gov (United States)

Aston, Elizabeth R; Farris, Samantha G; MacKillop, James; Metrik, Jane

2017-08-01

Drug demand, or relative value, can be assessed via analysis of behavioral economic purchase task performance. Five demand indices are typically obtained from drug purchase tasks. The goal of this research was to determine whether metrics of marijuana reinforcement from a marijuana purchase task (MPT) exhibit a latent factor structure that efficiently characterizes marijuana demand. Participants were regular marijuana users (n = 99; 37.4% female, 71.5% marijuana use days [5 days/week], 15.2% cannabis dependent) who completed study assessments, including the MPT, during a baseline session. Principal component analysis was used to examine the latent structure underlying MPT indices. Concurrent validity was assessed via examination of relationships between latent factors and marijuana use, past quit attempts, and marijuana expectancies. A two-factor solution was confirmed as the best fitting structure, accounting for 88.5% of the overall variance. Factor 1 (65.8% variance) reflected "Persistence," indicating sensitivity to escalating marijuana price, which comprised four MPT indices (elasticity, O max , P max , and breakpoint). Factor 2 (22.7% variance) reflected "Amplitude," indicating the amount consumed at unrestricted price (intensity). Persistence factor scores were associated with fewer past marijuana quit attempts and lower expectancies of negative use outcomes. Amplitude factor scores were associated with more frequent use, dependence symptoms, craving severity, and positive marijuana outcome expectancies. Consistent with research on alcohol and cigarette purchase tasks, the MPT can be characterized with a latent two-factor structure. Thus, demand for marijuana appears to encompass distinct dimensions of price sensitivity and volumetric consumption, with differential relations to other aspects of marijuana motivation.

Mental toughness latent profiles in endurance athletes.

Directory of Open Access Journals (Sweden)

Joanna S Zeiger

Full Text Available Mental toughness in endurance athletes, while an important factor for success, has been scarcely studied. An online survey was used to examine eight mental toughness factors in endurance athletes. The study aim was to determine mental toughness profiles via latent profile analysis in endurance athletes and whether associations exist between the latent profiles and demographics and sports characteristics. Endurance athletes >18 years of age were recruited via social media outlets (n = 1245, 53% female. Mental toughness was measured using the Sports Mental Toughness Questionnaire (SMTQ, Psychological Performance Inventory-Alternative (PPI-A, and self-esteem was measured using the Rosenberg Self-Esteem Scale (RSE. A three-class solution emerged, designated as high mental toughness (High MT, moderate mental toughness (Moderate MT and low mental toughness (Low MT. ANOVA tests showed significant differences between all three classes on all 8 factors derived from the SMTQ, PPI-A and the RSE. There was an increased odds of being in the High MT class compared to the Low MT class for males (OR = 1.99; 95% CI, 1.39, 2.83; P<0.001, athletes who were over 55 compared to those who were 18-34 (OR = 2.52; 95% CI, 1.37, 4.62; P<0.01, high sports satisfaction (OR = 8.17; 95% CI, 5.63, 11.87; P<0.001, and high division placement (OR = 2.18; 95% CI, 1.46,3.26; P<0.001. The data showed that mental toughness latent profiles exist in endurance athletes. High MT is associated with demographics and sports characteristics. Mental toughness screening in athletes may help direct practitioners with mental skills training.

Polarization-based and specular-reflection-based noncontact latent fingerprint imaging and lifting

Science.gov (United States)

Lin, Shih-Schön; Yemelyanov, Konstantin M.; Pugh, Edward N., Jr.; Engheta, Nader

2006-09-01

In forensic science the finger marks left unintentionally by people at a crime scene are referred to as latent fingerprints. Most existing techniques to detect and lift latent fingerprints require application of a certain material directly onto the exhibit. The chemical and physical processing applied to the fingerprint potentially degrades or prevents further forensic testing on the same evidence sample. Many existing methods also have deleterious side effects. We introduce a method to detect and extract latent fingerprint images without applying any powder or chemicals on the object. Our method is based on the optical phenomena of polarization and specular reflection together with the physiology of fingerprint formation. The recovered image quality is comparable to existing methods. In some cases, such as the sticky side of tape, our method shows unique advantages.

Hidden Markov latent variable models with multivariate longitudinal data.

Science.gov (United States)

Song, Xinyuan; Xia, Yemao; Zhu, Hongtu

2017-03-01

Cocaine addiction is chronic and persistent, and has become a major social and health problem in many countries. Existing studies have shown that cocaine addicts often undergo episodic periods of addiction to, moderate dependence on, or swearing off cocaine. Given its reversible feature, cocaine use can be formulated as a stochastic process that transits from one state to another, while the impacts of various factors, such as treatment received and individuals' psychological problems on cocaine use, may vary across states. This article develops a hidden Markov latent variable model to study multivariate longitudinal data concerning cocaine use from a California Civil Addict Program. The proposed model generalizes conventional latent variable models to allow bidirectional transition between cocaine-addiction states and conventional hidden Markov models to allow latent variables and their dynamic interrelationship. We develop a maximum-likelihood approach, along with a Monte Carlo expectation conditional maximization (MCECM) algorithm, to conduct parameter estimation. The asymptotic properties of the parameter estimates and statistics for testing the heterogeneity of model parameters are investigated. The finite sample performance of the proposed methodology is demonstrated by simulation studies. The application to cocaine use study provides insights into the prevention of cocaine use. © 2016, The International Biometric Society.

[Latent Class Analysis of Gambling Activities among Korean Adolescents].

Science.gov (United States)

Kang, Kyonghwa; Kim, Hyeongsu; Park, Ae Ran; Kim, Hee Young; Lee, Kunsei

2018-04-01

The aim of this study is to identify the types of gambling among adolescents and provide basic prevention information regarding adolescents' gambling problems. Secondary data from representative national survey on 2015 Youth Gambling Problems of Korea Center on Gambling Problems were used. Using latent class analysis (LCA), 13 gambling types such as offline and online games of 14,011 adolescents were classified, and gambling experiences and characteristics were analyzed. The subgroups of adolescent gambling were identified as four latent classes: a rare group (84.5% of the sample), a risk group (1.0%), an offline group (11.9%), and an expanded group (2.6%). The types and characteristics of gambling among the latent classes differed. In the risk group, adolescents participated in online illegal sports betting and internet casino, and gambling time, gambling expenses, and the number of gambling types were higher than other groups. Gambling frequently occur among adolescent, and the subtypes of gambling did not reveal homogeneous characteristics. In order to prevent adolescent gambling problems, it is a necessary to develop tailored prevention intervention in the nursing field, which is appropriate to the characteristics of adolescent gambling group and can help with early identification. © 2018 Korean Society of Nursing Science.

The mazEF toxin-antitoxin system as an attractive target in clinical isolates of Enterococcus faecium and Enterococcus faecalis.

Science.gov (United States)

Soheili, Sara; Ghafourian, Sobhan; Sekawi, Zamberi; Neela, Vasantha Kumari; Sadeghifard, Nourkhoda; Taherikalani, Morovat; Khosravi, Afra; Ramli, Ramliza; Hamat, Rukman Awang

2015-01-01

The toxin-antitoxin (TA) system is a regulatory system where two sets of genes encode the toxin and its corresponding antitoxin. In this study, the prevalence of TA systems in independently isolated clinical isolates of Enterococcus faecium and Enterococcus faecalis was determined, the dominant TA system was identified, different virulence genes in E. faecium and E. faecalis were surveyed, the level of expression of the virulence and TA genes in normal and stress conditions was determined, and finally their associations with the TA genes were defined. Remarkably, the analysis demonstrated higBA and mazEF in all clinical isolates, and their locations were on chromosomes and plasmids, respectively. On the other hand, a quantitative analysis of TA and virulence genes revealed that the expression level in both genes is different under normal and stress conditions. The results obtained by anti-mazF peptide nucleic acids demonstrated that the expression level of virulence genes had decreased. These findings demonstrate an association between TA systems and virulence factors. The mazEF on the plasmids and the higBA TA genes on the chromosomes of all E. faecium and E. faecalis strains were dominant. Additionally, there was a decrease in the expression of virulence genes in the presence of anti-mazF peptide nucleic acids. Therefore, it is suggested that mazEF TA systems are potent and sensitive targets in all E. faecium and E. faecalis strains.

The mazEF toxin–antitoxin system as an attractive target in clinical isolates of Enterococcus faecium and Enterococcus faecalis

Science.gov (United States)

Soheili, Sara; Ghafourian, Sobhan; Sekawi, Zamberi; Neela, Vasantha Kumari; Sadeghifard, Nourkhoda; Taherikalani, Morovat; Khosravi, Afra; Ramli, Ramliza; Hamat, Rukman Awang

2015-01-01

The toxin–antitoxin (TA) system is a regulatory system where two sets of genes encode the toxin and its corresponding antitoxin. In this study, the prevalence of TA systems in independently isolated clinical isolates of Enterococcus faecium and Enterococcus faecalis was determined, the dominant TA system was identified, different virulence genes in E. faecium and E. faecalis were surveyed, the level of expression of the virulence and TA genes in normal and stress conditions was determined, and finally their associations with the TA genes were defined. Remarkably, the analysis demonstrated higBA and mazEF in all clinical isolates, and their locations were on chromosomes and plasmids, respectively. On the other hand, a quantitative analysis of TA and virulence genes revealed that the expression level in both genes is different under normal and stress conditions. The results obtained by anti-mazF peptide nucleic acids demonstrated that the expression level of virulence genes had decreased. These findings demonstrate an association between TA systems and virulence factors. The mazEF on the plasmids and the higBA TA genes on the chromosomes of all E. faecium and E. faecalis strains were dominant. Additionally, there was a decrease in the expression of virulence genes in the presence of anti-mazF peptide nucleic acids. Therefore, it is suggested that mazEF TA systems are potent and sensitive targets in all E. faecium and E. faecalis strains. PMID:26005332

Determination of tumour hypoxia with the PET tracer [{sup 18}F]EF3: improvement of the tumour-to-background ratio in a mouse tumour model

Energy Technology Data Exchange (ETDEWEB)

Christian, Nicolas; Bol, Anne; Bast, Marc de; Labar, Daniel; Lee, John; Mahy, Pierre; Gregoire, Vincent [Universite Catholique de Louvain, Center for Molecular Imaging and Experimental Radiotherapy, Brussels (Belgium)

2007-09-15

The 2-(2-nitroimidazol-1-yl)-N-(3,3,3-trifluoropropyl)acetamide (EF3) is a 2-nitroimidazole derivative which undergoes bioreductive activation under hypoxic conditions. Using the PET tracer [{sup 18}F]EF3 in mice, tumour-to-muscle ratios ranging from 1.3 to 3.5 were observed. This study investigated the impact of various interventions aimed at increasing [{sup 18}F]EF3 elimination, thus potentially increasing the tumour-to-noise ratio in mice, by increasing the renal filtration rate (spironolactone, furosemide), decreasing tubular re-absorption (metronidazole, ornidazole, amino acid solution) or stimulating gastro-intestinal elimination (phenobarbital). C3H mice were injected i.v. with an average of 12.95 MBq of [{sup 18}F]EF3. Drugs were injected i.v. 15 min before the tracer or daily 4 days prior to the experiment (phenobarbital). Anaesthetised mice were imaged from 30 to 300 min with a dedicated animal PET (Mosaic, Philips). Regions of interest were delineated around the tumour, bladder, heart, liver and leg muscle. Radioactivity was expressed as a percentage of injected activity per gram of tissue. Ornidazole decreased the urinary excretion and increased the liver uptake of [{sup 18}F]EF3, but without causing any changes in the other organs. Phenobarbital significantly increased the liver concentration and decreased radioactivity in blood and muscle without affecting the tracer uptake in tumour. Consequently, a small but non-significant increase in tumour-to-noise ratio was observed. Although some effects were observed with other drugs, they did not modify the tumour-to-noise ratio. Only phenobarbital induced a trend toward an increased tumour-to-noise ratio that could possibly be tested in the clinical situation. (orig.)

Latent Membrane Protein 1 as a molecular adjuvant for single-cycle lentiviral vaccines

Directory of Open Access Journals (Sweden)

Rahmberg Andrew R

2011-05-01

Full Text Available Abstract Background Molecular adjuvants are a promising method to enhance virus-specific immune responses and protect against HIV-1 infection. Immune activation by ligands for receptors such as CD40 can induce dendritic cell activation and maturation. Here we explore the incorporation of two CD40 mimics, Epstein Barr Virus gene LMP1 or an LMP1-CD40 chimera, into a strain of SIV that was engineered to be limited to a single cycle of infection. Results Full length LMP1 or the chimeric protein LMP1-CD40 was cloned into the nef-locus of single-cycle SIV. Human and Macaque monocyte derived macrophages and DC were infected with these viruses. Infected cells were analyzed for activation surface markers by flow cytometry. Cells were also analyzed for secretion of pro-inflammatory cytokines IL-1β, IL-6, IL-8, IL-12p70 and TNF by cytometric bead array. Conclusions Overall, single-cycle SIV expressing LMP1 and LMP1-CD40 produced a broad and potent TH1-biased immune response in human as well as rhesus macaque macrophages and DC when compared with control virus. Single-cycle SIV-LMP1 also enhanced antigen presentation by lentiviral vector vaccines, suggesting that LMP1-mediated immune activation may enhance lentiviral vector vaccines against HIV-1.

Specific heat and magnetization of a ZrB12 single crystal: characterization of a type II/1 superconductor

OpenAIRE

Wang, Yuxing; Lortz, Rolf; Paderno, Yuriy; Filippov, Vladimir; Abe, Satoko; Tutsch, Ulrich; Junod, Alain

2005-01-01

We measured the specific heat, the magnetization, and the magnetoresistance of a single crystal of ZrB12, which is superconducting below Tc ~ 6 K. The specific heat in zero field shows a BCS-type superconducting transition. The normal- to superconducting-state transition changes from first order (with a latent heat) to second order (without latent heat) with increasing magnetic field, indicating that the pure compound is a low-kappa, type-II/1 superconductor in the classification of Auer and ...

Broad CTL response is required to clear latent HIV-1 due to dominance of escape mutations

Science.gov (United States)

Deng, Kai; Pertea, Mihaela; Rongvaux, Anthony; Wang, Leyao; Durand, Christine M.; Ghiaur, Gabriel; Lai, Jun; McHugh, Holly L.; Hao, Haiping; Zhang, Hao; Margolick, Joseph B.; Gurer, Cagan; Murphy, Andrew J.; Valenzuela, David M.; Yancopoulos, George D.; Deeks, Steven G.; Strowig, Till; Kumar, Priti; Siliciano, Janet D.; Salzberg, Steven L.; Flavell, Richard A.; Shan, Liang; Siliciano, Robert F.

2015-01-01

Despite antiretroviral therapy (ART), HIV-1 persists in a stable latent reservoir1, 2, primarily in resting memory CD4+ T cells3, 4. This reservoir presents a major barrier to the cure of HIV-1 infection. To purge the reservoir, pharmacological reactivation of latent HIV-1 has been proposed5 and tested both in vitro and in vivo6–8. A key remaining question is whether virus-specific immune mechanisms including cytolytic T lymphocytes (CTL) can clear infected cells in ART-treated patients after latency is reversed. Here we show that there is a striking all or none pattern for CTL escape mutations in HIV-1 Gag epitopes. Unless ART is started early, the vast majority (>98%) of latent viruses carry CTL escape mutations that render infected cells insensitive to CTLs directed at common epitopes. To solve this problem, we identified CTLs that could recognize epitopes from latent HIV-1 that were unmutated in every chronically infected patient tested. Upon stimulation, these CTLs eliminated target cells infected with autologous virus derived from the latent reservoir, both in vitro and in patient-derived humanized mice. The predominance of CTL-resistant viruses in the latent reservoir poses a major challenge to viral eradication. Our results demonstrate that chronically infected patients retain a broad spectrum viral-specific CTL response and that appropriate boosting of this response may be required for the elimination of the latent reservoir. PMID:25561180

Cost-effectiveness of post-landing latent tuberculosis infection control strategies in new migrants to Canada.

Science.gov (United States)

Campbell, Jonathon R; Johnston, James C; Sadatsafavi, Mohsen; Cook, Victoria J; Elwood, R Kevin; Marra, Fawziah

2017-01-01

The majority of tuberculosis in migrants to Canada occurs due to reactivation of latent TB infection. Risk of tuberculosis in those with latent tuberculosis infection can be significantly reduced with treatment. Presently, only 2.4% of new migrants are flagged for post-landing surveillance, which may include latent tuberculosis infection screening; no other migrants receive routine latent tuberculosis infection screening. To aid in reducing the tuberculosis burden in new migrants to Canada, we determined the cost-effectiveness of using different latent tuberculosis infection interventions in migrants under post-arrival surveillance and in all new migrants. A discrete event simulation model was developed that focused on a Canadian permanent resident cohort after arrival in Canada, utilizing a ten-year time horizon, healthcare system perspective, and 1.5% discount rate. Latent tuberculosis infection interventions were evaluated in the population under surveillance (N = 6100) and the total cohort (N = 260,600). In all evaluations, six different screening and treatment combinations were compared to the base case of tuberculin skin test screening followed by isoniazid treatment only in the population under surveillance. Quality adjusted life years, incident tuberculosis cases, and costs were recorded for each intervention and incremental cost-effectiveness ratios were calculated in relation to the base case. In the population under surveillance (N = 6100), using an interferon-gamma release assay followed by rifampin was dominant compared to the base case, preventing 4.90 cases of tuberculosis, a 4.9% reduction, adding 4.0 quality adjusted life years, and saving $353,013 over the ensuing ten-years. Latent tuberculosis infection screening in the total population (N = 260,600) was not cost-effective when compared to the base case, however could potentially prevent 21.8% of incident tuberculosis cases. Screening new migrants under surveillance with an interferon

Heterologous expression of a plastid EF-Tu reduces protein thermal aggregation and enhances CO2 fixation in wheat (Triticum aestivum) following heat stress.

Science.gov (United States)

Fu, Jianming; Momcilović, Ivana; Clemente, Thomas E; Nersesian, Natalya; Trick, Harold N; Ristic, Zoran

2008-10-01

Heat stress is a major constraint to wheat production and negatively impacts grain quality, causing tremendous economic losses, and may become a more troublesome factor due to global warming. At the cellular level, heat stress causes denaturation and aggregation of proteins and injury to membranes leading to alterations in metabolic fluxes. Protein aggregation is irreversible, and protection of proteins from thermal aggregation is a strategy a cell uses to tolerate heat stress. Here we report on the development of transgenic wheat (Triticum aestivum) events, expressing a maize gene coding for plastidal protein synthesis elongation factor (EF-Tu), which, compared to non-transgenic plants, display reduced thermal aggregation of leaf proteins, reduced heat injury to photosynthetic membranes (thylakoids), and enhanced rate of CO(2) fixation after exposure to heat stress. The results support the concept that EF-Tu ameliorates negative effects of heat stress by acting as a molecular chaperone. This is the first demonstration of the introduction of a plastidal EF-Tu in plants that leads to protection against heat injury and enhanced photosynthesis after heat stress. This is also the first demonstration that a gene other than HSP gene can be used for improvement of heat tolerance and that the improvement is possible in a species that has a complex genome, hexaploid wheat. The results strongly suggest that heat tolerance of wheat, and possibly other crop plants, can be improved by modulating expression of plastidal EF-Tu and/or by selection of genotypes with increased endogenous levels of this protein.

Ultra high temperature latent heat energy storage and thermophotovoltaic energy conversion

OpenAIRE

Datas Medina, Alejandro; Ramos Cabal, Alba; Martí Vega, Antonio; Cañizo Nadal, Carlos del; Luque López, Antonio

2016-01-01

A conceptual energy storage system design that utilizes ultra high temperature phase change materials is presented. In this system, the energy is stored in the form of latent heat and converted to electricity upon demand by TPV (thermophotovoltaic) cells. Silicon is considered in this study as PCM (phase change material) due to its extremely high latent heat (1800 J/g or 500 Wh/kg), melting point (1410 C), thermal conductivity (~25 W/mK), low cost (less than $2/kg or $4/kWh) and a...

Forensic Chemistry: The Revelation of Latent Fingerprints

Science.gov (United States)

Friesen, J. Brent

2015-01-01

The visualization of latent fingerprints often involves the use of a chemical substance that creates a contrast between the fingerprint residues and the surface on which the print was deposited. The chemical-aided visualization techniques can be divided into two main categories: those that chemically react with the fingerprint residue and those…

The Latent Class Structure of Chinese Patients with Eating Disorders in Shanghai.

Science.gov (United States)

Zheng, Yuchen; Kang, Qing; Huang, Jiabin; Jiang, Wenhui; Liu, Qiang; Chen, Han; Fan, Qing; Wang, Zhen; Chen, Jue; Xiao, Zeping

2017-08-25

Eating disorder is culture related, and the clinical symptoms are different between eastern and western patients. So the validity of feeding and eating disorders in the upcoming ICD-11 guide for Chinese patients is unclear. To explore the latent class structure of Chinese patients with eating disorder and the cross-cultural validity of the eating disorder section of the new ICD-11 guide in China. A total of 379 patients with eating disorders at Shanghai Mental Health Center were evaluated using the EDI questionnaire and a questionnaire developed by researchers from 2010 to 2016. SPSS 20.0 was used to enter data and analyze demographic data, and Latent GOLD was employed to conduct latent profile analysis. According to the results of latent profile analysis, patients with eating disorder were divided into five classes: low-weight fasting class (23.1%), non-fat-phobic binge/purge class (21.54%), low-fat-phobic binge class (19.27%), fat-phobic binge class (19.27%), and non-fat-phobic low-weight class (16.76%). Among the clinical symptoms extracted, there were significant differences in Body Mass Index (BMI), binge eating behavior, self-induced vomiting, laxative use and fat-phobic opinion; while there was no significant difference in restrictive food intake. Based on the clinical symptoms, there are five latent classes in Chinese patients with eating disorder, which is in accordance with the diagnostic categories of feeding and eating disorder in ICD-11. However, further work is needed in improving the fat-phobic opinion of patients with eating disorder and clarifying the BMI standard of thinness in the Chinese population.

Application of a latent class analysis to empirically define eating disorder phenotypes.

Science.gov (United States)

Keel, Pamela K; Fichter, Manfred; Quadflieg, Norbert; Bulik, Cynthia M; Baxter, Mark G; Thornton, Laura; Halmi, Katherine A; Kaplan, Allan S; Strober, Michael; Woodside, D Blake; Crow, Scott J; Mitchell, James E; Rotondo, Alessandro; Mauri, Mauro; Cassano, Giovanni; Treasure, Janet; Goldman, David; Berrettini, Wade H; Kaye, Walter H

2004-02-01

Diagnostic criteria for eating disorders influence how we recognize, research, and treat eating disorders, and empirically valid phenotypes are required for revealing their genetic bases. To empirically define eating disorder phenotypes. Data regarding eating disorder symptoms and features from 1179 individuals with clinically significant eating disorders were submitted to a latent class analysis. The resulting latent classes were compared on non-eating disorder variables in a series of validation analyses. Multinational, collaborative study with cases ascertained through diverse clinical settings (inpatient, outpatient, and community). Members of affected relative pairs recruited for participation in genetic studies of eating disorders in which probands met DSM-IV-TR criteria for anorexia nervosa (AN) or bulimia nervosa and had at least 1 biological relative with a clinically significant eating disorder. Main Outcome Measure Number and clinical characterization of latent classes. A 4-class solution provided the best fit. Latent class 1 (LC1) resembled restricting AN; LC2, AN and bulimia nervosa with the use of multiple methods of purging; LC3, restricting AN without obsessive-compulsive features; and LC4, bulimia nervosa with self-induced vomiting as the sole form of purging. Biological relatives were significantly likely to belong to the same latent class. Across validation analyses, LC2 demonstrated the highest levels of psychological disturbance, and LC3 demonstrated the lowest. The presence of obsessive-compulsive features differentiates among individuals with restricting AN. Similarly, the combination of low weight and multiple methods of purging distinguishes among individuals with binge eating and purging behaviors. These results support some of the distinctions drawn within the DSM-IV-TR among eating disorder subtypes, while introducing new features to define phenotypes.

Resveratrol Reactivates Latent HIV through Increasing Histone Acetylation and Activating Heat Shock Factor 1.

Science.gov (United States)

Zeng, Xiaoyun; Pan, Xiaoyan; Xu, Xinfeng; Lin, Jian; Que, Fuchang; Tian, Yuanxin; Li, Lin; Liu, Shuwen

2017-06-07

The persistence of latent HIV reservoirs presents a significant challenge to viral eradication. Effective latency reversing agents (LRAs) based on "shock and kill" strategy are urgently needed. The natural phytoalexin resveratrol has been demonstrated to enhance HIV gene expression, although its mechanism remains unclear. In this study, we demonstrated that resveratrol was able to reactivate latent HIV without global T cell activation in vitro. Mode of action studies showed resveratrol-mediated reactivation from latency did not involve the activation of silent mating type information regulation 2 homologue 1 (SIRT1), which belonged to class-3 histone deacetylase (HDAC). However, latent HIV was reactivated by resveratrol mediated through increasing histone acetylation and activation of heat shock factor 1 (HSF1). Additionally, synergistic activation of the latent HIV reservoirs was observed under cotreatment with resveratrol and conventional LRAs. Collectively, this research reveals that resveratrol is a natural LRA and shows promise for HIV therapy.

Identification of subgroups of patients with low back pain using Latent Class Analysis

DEFF Research Database (Denmark)

Nielsen, Anne Mølgaard

questionnaire and the clinicians’ findings on a standardised examination of the low back. By using pattern recognition, subgroups of patients were identified within which their responses and scores are similar, and therefore the patients are more alike within the subgroups than across the subgroups. Latent......, the optimal application of the LCA method in this context is unknown and therefore, two methodological considerations were addressed during the process. Firstly, when using existing questionnaire data, whether using each single item or the summary scores would provide better subgroup information. Secondly...... the questionnaires was preferred, due to the more nuanced description available within the resulting subgroups. Therefore, the single‐item strategy was used in the subsequent single‐stage and two‐stage LCA, which identified seven and nine patient subgroups, respectively, with similar face validity and adequate...

Development of molecular tests for the detection of ILAR and latent viruses in fruit trees.

Science.gov (United States)

Roussel, S; Kummert, J; Dutrecq, O; Lepoivre, P; Jijakli, M H

2004-01-01

The detection throughout the year of latent and ILAR viruses in fruit tress by classical serological tests appear to be unreliable. We have developed RT-PCR tests for a reliable detection of latent and ILAR viruses in fruit trees. These assays were then simplified to allow the direct use of crude plant extracts instead of total RNA preparations, and the analyses of pooled samples. In this way, such RT-PCR protocols are suitable for a routine diagnosis of latent and ILAR viruses in fruit tree certification.

Using existing questionnaires in latent class analysis: should we use summary scores or single items as input? A methodological study using a cohort of patients with low back pain

Directory of Open Access Journals (Sweden)

Nielsen AM

2016-04-01

Full Text Available Anne Molgaard Nielsen,1 Werner Vach,2 Peter Kent,1,3 Lise Hestbaek,1,4 Alice Kongsted1,4 1Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark; 2Center for Medical Biometry and Medical Informatics, Medical Center, University of Freiburg, Freiburg, Germany; 3School of Physiotherapy and Exercise Science, Curtin University, Perth, Australia; 4Nordic Institute of Chiropractic and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark Background: Latent class analysis (LCA is increasingly being used in health research, but optimal approaches to handling complex clinical data are unclear. One issue is that commonly used questionnaires are multidimensional, but expressed as summary scores. Using the example of low back pain (LBP, the aim of this study was to explore and descriptively compare the application of LCA when using questionnaire summary scores and when using single items to subgrouping of patients based on multidimensional data. Materials and methods: Baseline data from 928 LBP patients in an observational study were classified into four health domains (psychology, pain, activity, and participation using the World Health Organization’s International Classification of Functioning, Disability, and Health framework. LCA was performed within each health domain using the strategies of summary-score and single-item analyses. The resulting subgroups were descriptively compared using statistical measures and clinical interpretability. Results: For each health domain, the preferred model solution ranged from five to seven subgroups for the summary-score strategy and seven to eight subgroups for the single-item strategy. There was considerable overlap between the results of the two strategies, indicating that they were reflecting the same underlying data structure. However, in three of the four health domains, the single-item strategy resulted in a more nuanced description, in terms

A stable latent reservoir for HIV-1 in resting CD4+ T lymphocytes in infected children

Science.gov (United States)

Persaud, Deborah; Pierson, Theodore; Ruff, Christian; Finzi, Diana; Chadwick, Karen R.; Margolick, Joseph B.; Ruff, Andrea; Hutton, Nancy; Ray, Stuart; Siliciano, Robert F.

2000-01-01

HIV-1 persists in a latent state in resting CD4+ T lymphocytes of infected adults despite prolonged highly active antiretroviral therapy (HAART). To determine whether a latent reservoir for HIV-1 exists in infected children, we performed a quantitative viral culture assay on highly purified resting CD4+ T cells from 21 children with perinatally acquired infection. Replication-competent HIV-1 was recovered from all 18 children from whom sufficient cells were obtained. The frequency of latently infected resting CD4+ T cells directly correlated with plasma virus levels, suggesting that in children with ongoing viral replication, most latently infected cells are in the labile preintegration state of latency. However, in each of 7 children who had suppression of viral replication to undetectable levels for 1–3 years on HAART, latent replication-competent HIV-1 persisted with little decay, owing to a stable reservoir of infected cells in the postintegration stage of latency. Drug-resistance mutations generated by previous nonsuppressive regimens persisted in this compartment despite more than 1 year of fully suppressive HAART, rendering untenable the idea of recycling drugs that were part of failed regimens. Thus the latent reservoir for HIV-1 in resting CD4+ T cells will be a major obstacle to HIV-1 eradication in children. PMID:10749578

Friction massage versus kinesiotaping for short-term management of latent trigger points in the upper trapezius: a randomized controlled trial.

Science.gov (United States)

Mohamadi, Marzieh; Piroozi, Soraya; Rashidi, Iman; Hosseinifard, Saeed

2017-01-01

Latent trigger points in the upper trapezius muscle may disrupt muscle movement patterns and cause problems such as cramping and decreased muscle strength. Because latent trigger points may spontaneously become active trigger points, they should be addressed and treated to prevent further problems. In this study we compared the short-term effect of kinesiotaping versus friction massage on latent trigger points in the upper trapezius muscle. Fifty-eight male students enrolled with a stratified sampling method participated in this single-blind randomized clinical trial (Registration ID: IRCT2016080126674N3) in 2016. Pressure pain threshold was recorded with a pressure algometer and grip strength was recorded with a Collin dynamometer. The participants were randomly assigned to two different treatment groups: kinesiotape or friction massage. Friction massage was performed daily for 3 sessions and kinesiotape was used for 72 h. One hour after the last session of friction massage or removal of the kinesiotape, pressure pain threshold and grip strength were evaluated again. Pressure pain threshold decreased significantly after both friction massage (2.66 ± 0.89 to 2.25 ± 0.76; P  = 0.02) and kinesiotaping (2.00 ± 0.74 to 1.71 ± 0.65; P  = 0.01). Grip strength increased significantly after friction massage (40.78 ± 9.55 to 42.17 ± 10.68; P  = 0.03); however there was no significant change in the kinesiotape group (39.72 ± 6.42 to 40.65 ± 7.3; P  = 0.197). There were no significant differences in pressure pain threshold (2.10 ± 0.11 & 1.87 ± 0.11; P  = 0.66) or grip strength (42.17 ± 10.68 & 40.65 ± 7.3; P  = 0.53) between the two study groups. Friction massage and kinesiotaping had identical short-term effects on latent trigger points in the upper trapezius. Three sessions of either of these two interventions did not improve latent trigger points. Registration ID in IRCT: IRCT2016080126674N3.

A Latent Class Regression Analysis of Men's Conformity to Masculine Norms and Psychological Distress

Science.gov (United States)

Wong, Y. Joel; Owen, Jesse; Shea, Munyi

2012-01-01

How are specific dimensions of masculinity related to psychological distress in specific groups of men? To address this question, the authors used latent class regression to assess the optimal number of latent classes that explained differential relationships between conformity to masculine norms and psychological distress in a racially diverse…

New approaches for examining associations with latent categorical variables: applications to substance abuse and aggression.

Science.gov (United States)

Feingold, Alan; Tiberio, Stacey S; Capaldi, Deborah M

2014-03-01

Assessments of substance use behaviors often include categorical variables that are frequently related to other measures using logistic regression or chi-square analysis. When the categorical variable is latent (e.g., extracted from a latent class analysis [LCA]), classification of observations is often used to create an observed nominal variable from the latent one for use in a subsequent analysis. However, recent simulation studies have found that this classical 3-step analysis championed by the pioneers of LCA produces underestimates of the associations of latent classes with other variables. Two preferable but underused alternatives for examining such linkages-each of which is most appropriate under certain conditions-are (a) 3-step analysis, which corrects the underestimation bias of the classical approach, and (b) 1-step analysis. The purpose of this article is to dissuade researchers from conducting classical 3-step analysis and to promote the use of the 2 newer approaches that are described and compared. In addition, the applications of these newer models-for use when the independent, the dependent, or both categorical variables are latent-are illustrated through substantive analyses relating classes of substance abusers to classes of intimate partner aggressors.

Effect of acycloguanosine treatment of acute and latent herpes simplex infections in mice.

Science.gov (United States)

Field, H J; Bell, S E; Elion, G B; Nash, A A; Wildy, P

1979-04-01

Systemic treatment of mice with the nucleoside analog 9-(2-hydroxyethoxymethyl)guanine (acycloguanosine [aciclovir]) was found to be highly effective against acute type 1 herpes simplex virus infection of the pinna. The drug ablated clinical signs and reduced virus replication both in tissue local to the inoculation site and within the nervous system. Provided that moderate-sized virus inocula were used, acycloguanosine treatment reduced or prevented the establishment of a latent infection in the dorsal root ganglia relating to the sensory nerve supply of the ear. However, although it aborted artificially produced infections in dorsal root ganglia, acycloguanosine was found not to be effective against the latent infection once established. This finding strongly indicated that latent herpes simplex virus in mice can exist in a nonreplicating form.

A Framework for Reproducible Latent Fingerprint Enhancements.

Science.gov (United States)

Carasso, Alfred S

2014-01-01

Photoshop processing of latent fingerprints is the preferred methodology among law enforcement forensic experts, but that appproach is not fully reproducible and may lead to questionable enhancements. Alternative, independent, fully reproducible enhancements, using IDL Histogram Equalization and IDL Adaptive Histogram Equalization, can produce better-defined ridge structures, along with considerable background information. Applying a systematic slow motion smoothing procedure to such IDL enhancements, based on the rapid FFT solution of a Lévy stable fractional diffusion equation, can attenuate background detail while preserving ridge information. The resulting smoothed latent print enhancements are comparable to, but distinct from, forensic Photoshop images suitable for input into automated fingerprint identification systems, (AFIS). In addition, this progressive smoothing procedure can be reexamined by displaying the suite of progressively smoother IDL images. That suite can be stored, providing an audit trail that allows monitoring for possible loss of useful information, in transit to the user-selected optimal image. Such independent and fully reproducible enhancements provide a valuable frame of reference that may be helpful in informing, complementing, and possibly validating the forensic Photoshop methodology.

Latent heat of traffic moving from rest

Science.gov (United States)

Farzad Ahmadi, S.; Berrier, Austin S.; Doty, William M.; Greer, Pat G.; Habibi, Mohammad; Morgan, Hunter A.; Waterman, Josam H. C.; Abaid, Nicole; Boreyko, Jonathan B.

2017-11-01

Contrary to traditional thinking and driver intuition, here we show that there is no benefit to ground vehicles increasing their packing density at stoppages. By systematically controlling the packing density of vehicles queued at a traffic light on a Smart Road, drone footage revealed that the benefit of an initial increase in displacement for close-packed vehicles is completely offset by the lag time inherent to changing back into a ‘liquid phase’ when flow resumes. This lag is analogous to the thermodynamic concept of the latent heat of fusion, as the ‘temperature’ (kinetic energy) of the vehicles cannot increase until the traffic ‘melts’ into the liquid phase. These findings suggest that in situations where gridlock is not an issue, drivers should not decrease their spacing during stoppages in order to lessen the likelihood of collisions with no loss in flow efficiency. In contrast, motion capture experiments of a line of people walking from rest showed higher flow efficiency with increased packing densities, indicating that the importance of latent heat becomes trivial for slower moving systems.

Lanthanide mixed ligand chelates for DNA profiling and latent fingerprint detection

Science.gov (United States)

Menzel, E. R.; Allred, Clay

1997-02-01

It is our aim to develop a universally applicable latent fingerprint detection method using lanthanide (rare-earth) complexes as a source of luminescence. Use of these lanthanide complexes offers advantages on several fronts, including benefits from large Stokes shifts, long luminescence lifetimes, narrow emissions, ability of sequential assembly of complexes, and chemical variability of the ligands. Proper exploitation of these advantages would lead to a latent fingerprint detection method superior to any currently available. These same characteristics also lend themselves to many of the problems associated with DNA processing in the forensic science context.

Age is associated with latent tuberculosis in nurses

Directory of Open Access Journals (Sweden)

Naesinee Chaiear

2016-12-01

Full Text Available Objective: To evaluate risk factors for developing latent tuberculosis (LTB in Thai nurses. Methods: A comparison study was conducted at Srinagarind Hospital, Khon Kaen, Thailand. Clinical factors were compared between persons with tuberculin conversion and those without tuberculin conversion identified by tuberculin skin test. Results: There were 173 eligible persons with the LTB (34.7%. There were five workplaces where participants worked regularly including the general ward, surgical ward, pediatric ward, medical ward and critical care ward. In a multivariate model, two factors were significantly associated with LTB including age and history of tuberculosis in colleagues. The adjusted odds ratio (95% confidence interval of both variables were 1.056 (1.004–1.104 and 0.202 (0.044– 0.941. Conclusions: Older age is associated with latent tuberculosis in nurses. LTB should be screened routinely and treated if diagnosed for nurses.

When do latent class models overstate accuracy for diagnostic and other classifiers in the absence of a gold standard?

Science.gov (United States)

Spencer, Bruce D

2012-06-01

Latent class models are increasingly used to assess the accuracy of medical diagnostic tests and other classifications when no gold standard is available and the true state is unknown. When the latent class is treated as the true class, the latent class models provide measures of components of accuracy including specificity and sensitivity and their complements, type I and type II error rates. The error rates according to the latent class model differ from the true error rates, however, and empirical comparisons with a gold standard suggest the true error rates often are larger. We investigate conditions under which the true type I and type II error rates are larger than those provided by the latent class models. Results from Uebersax (1988, Psychological Bulletin 104, 405-416) are extended to accommodate random effects and covariates affecting the responses. The results are important for interpreting the results of latent class analyses. An error decomposition is presented that incorporates an error component from invalidity of the latent class model. © 2011, The International Biometric Society.

The application of seasonal latent variable in forecasting electricity demand as an alternative method

International Nuclear Information System (INIS)

Sumer, Kutluk Kagan; Goktas, Ozlem; Hepsag, Aycan

2009-01-01

In this study, we used ARIMA, seasonal ARIMA (SARIMA) and alternatively the regression model with seasonal latent variable in forecasting electricity demand by using data that belongs to 'Kayseri and Vicinity Electricity Joint-Stock Company' over the 1997:1-2005:12 periods. This study tries to examine the advantages of forecasting with ARIMA, SARIMA methods and with the model has seasonal latent variable to each other. The results support that ARIMA and SARIMA models are unsuccessful in forecasting electricity demand. The regression model with seasonal latent variable used in this study gives more successful results than ARIMA and SARIMA models because also this model can consider seasonal fluctuations and structural breaks

Latent tuberculosis in HIV positive, diagnosed by the M. tuberculosis specific interferon-gamma test

DEFF Research Database (Denmark)

Brock, Inger; Ruhwald, Morten; Lundgren, Bettina

2006-01-01

Although tuberculosis (TB) is a minor problem in Denmark, severe and complicated cases occur in HIV positive. Since the new M. tuberculosis specific test for latent TB, the QuantiFERON-TB In-Tube test (QFT-IT) became available the patients in our clinic have been screened for the presence of latent...

Recovery of latent fingerprints and DNA on human skin.

Science.gov (United States)

Färber, Doris; Seul, Andrea; Weisser, Hans-Joachim; Bohnert, Michael

2010-11-01

The project "Latent Fingerprints and DNA on Human Skin" was the first systematic research in Europe dealing with detection of fingerprints and DNA left by offenders on the skin of corpses. One thousand samples gave results that allow general statements on the materials and methods used. The tests were carried out according to a uniform trial structure. Fingerprints were deposited by natural donors on corpses. The latent fingerprints were treated with magnetic powder or black fingerprint powder. Afterward, they were lifted with silicone casting material (Isomark(®)) or gelatine foil. All lifts were swabbed to recover DNA. It was possible to visualize comparable and identifiable fingerprints on the skin of corpses (16%). In the same categories, magnetic powder (18.4%) yielded better results than black fingerprint powder (13.6%). The number of comparable and identifiable fingerprints decreased on the lifts (12.7%). Isomark(®) (14.9%) was the better lifting material in comparison with gelatine foil (10.1%). In one-third of the samples, DNA could be extracted from the powdered and lifted latents. Black fingerprint powder delivered the better result with a rate of 2.2% for full DNA profiles and profiles useful for exclusion in comparison with 1.8% for the magnetic powder traces. Isomark(®) (3.1%) yielded better results than gelatine foil (0.6%). © 2010 American Academy of Forensic Sciences.

Latent cooling and microphysics effects in deep convection

Science.gov (United States)

Fernández-González, S.; Wang, P. K.; Gascón, E.; Valero, F.; Sánchez, J. L.

2016-11-01

Water phase changes within a storm are responsible for the enhancement of convection and therefore the elongation of its lifespan. Specifically, latent cooling absorbed during evaporation, melting and sublimation is considered the main cause of the intensification of downdrafts. In order to know more accurately the consequences of latent cooling caused by each of these processes (together with microphysical effects that they induce), four simulations were developed with the Wisconsin Dynamical and Microphysical Model (WISCDYMM): one with all the microphysical processes; other without sublimation; melting was suppressed in the third simulation; and evaporation was disabled in the fourth. The results show that sublimation cooling is not essential to maintain the vertical currents of the storm. This is demonstrated by the fact that in the simulation without sublimation, maximum updrafts are in the same range as in the control simulation, and the storm lifespan is similar or even longer. However, melting was of vital importance. The storm in the simulation without melting dissipated prematurely, demonstrating that melting is indispensable to the enhancement of downdrafts below the freezing level and for avoiding the collapse of low level updrafts. Perhaps the most important finding is the crucial influence of evaporative cooling above the freezing level that maintains and enhances mid-level downdrafts in the storm. It is believed that this latent cooling comes from the evaporation of supercooled liquid water connected with the Bergeron-Findeisen process. Therefore, besides its influence at low levels (which was already well known), this evaporative cooling is essential to strengthen mid-level downdrafts and ultimately achieve a quasi-steady state.

Managerial performance and cost efficiency of Japanese local public hospitals: a latent class stochastic frontier model.

Science.gov (United States)

Besstremyannaya, Galina

2011-09-01

The paper explores the link between managerial performance and cost efficiency of 617 Japanese general local public hospitals in 1999-2007. Treating managerial performance as unobservable heterogeneity, the paper employs a panel data stochastic cost frontier model with latent classes. Financial parameters associated with better managerial performance are found to be positively significant in explaining the probability of belonging to the more efficient latent class. The analysis of latent class membership was consistent with the conjecture that unobservable technological heterogeneity reflected in the existence of the latent classes is related to managerial performance. The findings may support the cause for raising efficiency of Japanese local public hospitals by enhancing the quality of management. Copyright © 2011 John Wiley & Sons, Ltd.

Effects of single antegrade hot shot in comparison with no hot shot administration during coronary artery bypass grafting

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Pouya Mirmohammadsadeghi

2015-05-01

Full Text Available BACKGROUND: Superior results will be achieved from cardiac surgery by minimizing the effect of ischemia/reperfusion injury during cross-clamping of the aorta. Different cardioplegia solutions have been introduced, but the optimum one is still ambiguous. The aim of this study is to determine the effect of single antegrade hot shot terminal warm blood cardioplegia (TWBC on patients who had undergone coronary artery bypass grafting (CABG. METHODS: In total, 2488 patients who had CABG surgery in Sina Hospital, Isfahan, Iran, from 2003 to 2011 were enrolled in this case-control study. They were divided into two groups, those who received cold cardioplegia only and those who received a hot shot following cold cardioplegia. Demographics, and clinical data, such as; premature atrial contraction (PAC arrhythmia, diabetes treatment, and left ventricular ejection fraction (EF, were collected and logistic regression analysis was used to analyze the data. RESULTS: There were significant differences found between subjects receiving antegrade hot shot based on direct current (DC shocks, with regard to; female, EF levels, diabetes treatment (P < 0.050. Those who did not receive the hot shot and were not diabetic received more DC shock (P = 0.019. The prevalence of subjects who did no need DC shock was significantly higher among male subjects who had good EF and acceptable diabetic treatment. Multiple logistic regression showed that PAC arrhythmia did not have a significant effect on receiving DC shock during CAGB [0.84 (0.25, 2.85, (P = 0.780]. Having poor EF increased the risk of receiving DC shock among subjects by 2.81 [(1.69, 4.69, (P ≤ 0.001] (P < 0.001. Among the diabetic subjects, receiving insulin decreased the risk of receiving DC shock by 0.54 (0.29, 0.98 (P = 0.042. CONCLUSION: It was concluded that single antegrade hot shot following cold cardioplegia was not particularly effective in the CABG group. TWBC will decrease the need for DC shock.   

Upper atmosphere tidal oscillations due to latent heat release in the tropical troposphere

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J. M. Forbes

1997-09-01

Full Text Available Latent heat release associated with tropical deep convective activity is investigated as a source for migrating (sun-synchronous diurnal and semidiurnal tidal oscillations in the 80–150-km height region. Satellite-based cloud brightness temperature measurements made between 1988 and 1994 and averaged into 3-h bins are used to determine the annual- and longitude-average local-time distribution of rainfall rate, and hence latent heating, between ±40° latitude. Regional average rainfall rates are shown to be in good agreement with climatological values derived from surface rain gauge data. A global linearized wave model is used to estimate the corresponding atmospheric perturbations in the mesosphere/lower thermosphere (80–150 km resulting from upward-propagating tidal components excited by the latent heating. The annual-average migrating diurnal and semidiurnal components achieve velocity and temperature amplitudes of order 10–20 m s–1 and 5–10 K, respectively, which represent substantial contributions to the dynamics of the region. The latent heat forcing also shifts the phase (local solar time of maximum of the semidiurnal surface pressure oscillation from 0912 to 0936 h, much closer to the observed value of 0944 h.

Detection of latent prints by Raman imaging

Science.gov (United States)

Lewis, Linda Anne [Andersonville, TN; Connatser, Raynella Magdalene [Knoxville, TN; Lewis, Sr., Samuel Arthur

2011-01-11

The present invention relates to a method for detecting a print on a surface, the method comprising: (a) contacting the print with a Raman surface-enhancing agent to produce a Raman-enhanced print; and (b) detecting the Raman-enhanced print using a Raman spectroscopic method. The invention is particularly directed to the imaging of latent fingerprints.

A structural equation modeling of executive functions, IQ and mathematical skills in primary students: Differential effects on number production, mental calculus and arithmetical problems.

Science.gov (United States)

Arán Filippetti, Vanessa; Richaud, María Cristina

2017-10-01

Though the relationship between executive functions (EFs) and mathematical skills has been well documented, little is known about how both EFs and IQ differentially support diverse math domains in primary students. Inconsistency of results may be due to the statistical techniques employed, specifically, if the analysis is conducted with observed variables, i.e., regression analysis, or at the latent level, i.e., structural equation modeling (SEM). The current study explores the contribution of both EFs and IQ in mathematics through an SEM approach. A total of 118 8- to 12-year-olds were administered measures of EFs, crystallized (Gc) and fluid (Gf) intelligence, and math abilities (i.e., number production, mental calculus and arithmetical problem-solving). Confirmatory factor analysis (CFA) offered support for the three-factor solution of EFs: (1) working memory (WM), (2) shifting, and (3) inhibition. Regarding the relationship among EFs, IQ and math abilities, the results of the SEM analysis showed that (i) WM and age predict number production and mental calculus, and (ii) shifting and sex predict arithmetical problem-solving. In all of the SEM models, EFs partially or totally mediated the relationship between IQ, age and math achievement. These results suggest that EFs differentially supports math abilities in primary-school children and is a more significant predictor of math achievement than IQ level.

Proliferation of latently infected CD4+ T cells carrying replication-competent HIV-1: Potential role in latent reservoir dynamics

Science.gov (United States)

Hosmane, Nina N.; Kwon, Kyungyoon J.; Bruner, Katherine M.; Capoferri, Adam A.; Rosenbloom, Daniel I.S.; Keele, Brandon F.; Ho, Ya-Chi

2017-01-01

A latent reservoir for HIV-1 in resting CD4+ T lymphocytes precludes cure. Mechanisms underlying reservoir stability are unclear. Recent studies suggest an unexpected degree of infected cell proliferation in vivo. T cell activation drives proliferation but also reverses latency, resulting in productive infection that generally leads to cell death. In this study, we show that latently infected cells can proliferate in response to mitogens without producing virus, generating progeny cells that can release infectious virus. Thus, assays relying on one round of activation underestimate reservoir size. Sequencing of independent clonal isolates of replication-competent virus revealed that 57% had env sequences identical to other isolates from the same patient. Identity was confirmed by full-genome sequencing and was not attributable to limited viral diversity. Phylogenetic and statistical analysis suggested that identical sequences arose from in vivo proliferation of infected cells, rather than infection of multiple cells by a dominant viral species. The possibility that much of the reservoir arises by cell proliferation presents challenges to cure. PMID:28341641

Proliferation of latently infected CD4+ T cells carrying replication-competent HIV-1: Potential role in latent reservoir dynamics.

Science.gov (United States)

Hosmane, Nina N; Kwon, Kyungyoon J; Bruner, Katherine M; Capoferri, Adam A; Beg, Subul; Rosenbloom, Daniel I S; Keele, Brandon F; Ho, Ya-Chi; Siliciano, Janet D; Siliciano, Robert F

2017-04-03

A latent reservoir for HIV-1 in resting CD4 + T lymphocytes precludes cure. Mechanisms underlying reservoir stability are unclear. Recent studies suggest an unexpected degree of infected cell proliferation in vivo. T cell activation drives proliferation but also reverses latency, resulting in productive infection that generally leads to cell death. In this study, we show that latently infected cells can proliferate in response to mitogens without producing virus, generating progeny cells that can release infectious virus. Thus, assays relying on one round of activation underestimate reservoir size. Sequencing of independent clonal isolates of replication-competent virus revealed that 57% had env sequences identical to other isolates from the same patient. Identity was confirmed by full-genome sequencing and was not attributable to limited viral diversity. Phylogenetic and statistical analysis suggested that identical sequences arose from in vivo proliferation of infected cells, rather than infection of multiple cells by a dominant viral species. The possibility that much of the reservoir arises by cell proliferation presents challenges to cure. © 2017 Hosmane et al.

Longitudinal mixed-effects models for latent cognitive function

NARCIS (Netherlands)

van den Hout, Ardo; Fox, Gerardus J.A.; Muniz-Terrera, Graciela

2015-01-01

A mixed-effects regression model with a bent-cable change-point predictor is formulated to describe potential decline of cognitive function over time in the older population. For the individual trajectories, cognitive function is considered to be a latent variable measured through an item response

Evaluation of AFIS-Ranked latent fingerprint matched templates

NARCIS (Netherlands)

Krish, Ram P.; Fierrez, Julian; Ramos, Daniel; Veldhuis, Raymond N.J.; Wang, Ruifang; Klette, Reinhard; Rivera, Mariano; Satoh, Shin'ichi

2013-01-01

The methodology currently practiced in latent print examination (known as ACE-V) yields only a decision as result, namely individualization, exclusion or inconclusive. From such a decision, it is not possible to express the strength of opinion of a forensic examiner quantitatively with a scientific

When Factorization Meets Heterogeneous Latent Topics：An Interpretable Cross-Site Recommendation Framework

Institute of Scientific and Technical Information of China (English)

辛欣; 林钦佑; 魏骁驰; 黄河燕

2015-01-01

Data sparsity is a well-known challenge in recommender systems. Previous studies alleviate this problem by incorporating the information within the corresponding social media site. In this paper, we solve this challenge by exploring cross-site information. Specifically, we examine: 1) how to effectively and efficiently utilize cross-site ratings and content features to improve recommendation performance and 2) how to make the recommendation interpretable by utilizing content features. We propose a joint model of matrix factorization and latent topic analysis. Heterogeneous content features are modeled by multiple kinds of latent topics. In addition, the combination of matrix factorization and latent topics makes the recommendation result interpretable. Therefore, the above two issues are simultaneously solved. Through a real-world dataset, where user behaviors in three social media sites are collected, we demonstrate that the proposed model is effective in improving recommendation performance and interpreting the rationale of ratings.

TH-A-19A-04: Latent Uncertainties and Performance of a GPU-Implemented Pre-Calculated Track Monte Carlo Method

International Nuclear Information System (INIS)

Renaud, M; Seuntjens, J; Roberge, D

2014-01-01

Purpose: Assessing the performance and uncertainty of a pre-calculated Monte Carlo (PMC) algorithm for proton and electron transport running on graphics processing units (GPU). While PMC methods have been described in the past, an explicit quantification of the latent uncertainty arising from recycling a limited number of tracks in the pre-generated track bank is missing from the literature. With a proper uncertainty analysis, an optimal pre-generated track bank size can be selected for a desired dose calculation uncertainty. Methods: Particle tracks were pre-generated for electrons and protons using EGSnrc and GEANT4, respectively. The PMC algorithm for track transport was implemented on the CUDA programming framework. GPU-PMC dose distributions were compared to benchmark dose distributions simulated using general-purpose MC codes in the same conditions. A latent uncertainty analysis was performed by comparing GPUPMC dose values to a “ground truth” benchmark while varying the track bank size and primary particle histories. Results: GPU-PMC dose distributions and benchmark doses were within 1% of each other in voxels with dose greater than 50% of Dmax. In proton calculations, a submillimeter distance-to-agreement error was observed at the Bragg Peak. Latent uncertainty followed a Poisson distribution with the number of tracks per energy (TPE) and a track bank of 20,000 TPE produced a latent uncertainty of approximately 1%. Efficiency analysis showed a 937× and 508× gain over a single processor core running DOSXYZnrc for 16 MeV electrons in water and bone, respectively. Conclusion: The GPU-PMC method can calculate dose distributions for electrons and protons to a statistical uncertainty below 1%. The track bank size necessary to achieve an optimal efficiency can be tuned based on the desired uncertainty. Coupled with a model to calculate dose contributions from uncharged particles, GPU-PMC is a candidate for inverse planning of modulated electron radiotherapy

Extending dynamic segmentation with lead generation : A latent class Markov analysis of financial product portfolios

NARCIS (Netherlands)

Paas, L.J.; Bijmolt, T.H.A.; Vermunt, J.K.

2004-01-01

A recent development in marketing research concerns the incorporation of dynamics in consumer segmentation.This paper extends the latent class Markov model, a suitable technique for conducting dynamic segmentation, in order to facilitate lead generation.We demonstrate the application of the latent

Space Flight-Induced Reactivation of Latent Epstein-Barr Virus

Science.gov (United States)

Stowe, Raymond P.; Barrett, Alan D. T.; Pierson, Duane L.

2001-01-01

Reactivation of latent Epstein-Barr virus (EBV) may be an important threat to crew health during extended space missions. Decreased cellular immune function has been reported both during and after space flight. Preliminary studies have demonstrated increased EBV shedding in saliva as well as increased antibody titers to EBV lytic proteins. We hypothesize that the combined effects of microgravity along with associated physical and psychological stress will decrease EBV-specific T-cell immunity and reactivate latent EBV in infected B-lymphocytes. If increased virus production and clonal expansion of infected B-lymphocytes are detected, then pharmacological measures can be developed and instituted prior to onset of overt clinical disease. More importantly, we will begin to understand the basic mechanisms involved in stress-induced reactivation of EBV in circulating B-lymphocytes.

Proof of U(VI) sorption on Acidovorax facilis by TRLFS and EF-TEM/EELS

Energy Technology Data Exchange (ETDEWEB)

Krawczyk-Baersch, Evelyn; Gerber, Ulrike [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Div. Biogeochemistry; Steudtner, Robin [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Div. Surface Processes

2016-07-01

In EF-TEM/EELS studies it was shown that U(VI) is sorbed mainly on the outer membrane of Acidovorax facilis. The results are supported by TRLFS measurements, which were performed on the pellet of the cells. In comparison to reference spectra of some cell membrane components, the measured emission spectra of the A. facilis pellet show the best agreement with those of the Uranyl-lipopolysaccharide-complex. Hence, it can be concluded that phosphoryl groups may be the main binding sites for uranyl, located in the lipopolysaccharide unit in the outer membrane.

Effect of stimulus intensity on latent inhibition: A case for generalization decrement

Directory of Open Access Journals (Sweden)

Gabriel Rodríguez

2002-01-01

Full Text Available En dos experimentos se empleó la técnica de aversión condicionada al sabor en ratas para examinar el efecto de la intensidad del estímulo expuesto sobre la inhibición latente. En el Experimento 1 se valoró el efecto de la exposición de un sabor dulce en distintas concentraciones sobre la tasa de adquisición de su condicionamiento posterior. Los resultados de este experimento mostraron un mayor efecto de inhibición latente tras la exposición del sabor en igual concentración a la empleada durante el condicionamiento (grupo EI que tras su exposición en una concentración mayor (grupo EM o menor (grupo Em. Además, esta atenuación del efecto de inhibición latente en las condiciones de cambio en la concentración resultó menor en el grupo EM que en el grupo Em. El Experimento 2 demostró que la generalización de las propiedades aversivas condicionadas al sabor fue mayor entre las concentraciones empleadas en el grupo EM que en el grupo Em. Estos resultados sugieren que el aparente efecto de la intensidad del estímulo en la inhibición latente podría ser explicado en términos de decremento en la generalización.

Transcriptional Reprogramming during Effector-to-Memory Transition Renders CD4+ T Cells Permissive for Latent HIV-1 Infection.

Science.gov (United States)

Shan, Liang; Deng, Kai; Gao, Hongbo; Xing, Sifei; Capoferri, Adam A; Durand, Christine M; Rabi, S Alireza; Laird, Gregory M; Kim, Michelle; Hosmane, Nina N; Yang, Hung-Chih; Zhang, Hao; Margolick, Joseph B; Li, Linghua; Cai, Weiping; Ke, Ruian; Flavell, Richard A; Siliciano, Janet D; Siliciano, Robert F

2017-10-17

The latent reservoir for HIV-1 in resting memory CD4 + T cells is the major barrier to curing HIV-1 infection. Studies of HIV-1 latency have focused on regulation of viral gene expression in cells in which latent infection is established. However, it remains unclear how infection initially becomes latent. Here we described a unique set of properties of CD4 + T cells undergoing effector-to-memory transition including temporary upregulation of CCR5 expression and rapid downregulation of cellular gene transcription. These cells allowed completion of steps in the HIV-1 life cycle through integration but suppressed HIV-1 gene transcription, thus allowing the establishment of latency. CD4 + T cells in this stage were substantially more permissive for HIV-1 latent infection than other CD4 + T cells. Establishment of latent HIV-1 infection in CD4 + T could be inhibited by viral-specific CD8 + T cells, a result with implications for elimination of latent HIV-1 infection by T cell-based vaccines. Copyright © 2017. Published by Elsevier Inc.

Effect of Acycloguanosine Treatment on Acute and Latent Herpes Simplex Infections in Mice

Science.gov (United States)

Field, Hugh J.; Bell, Susanne E.; Elion, Gertrude B.; Nash, Anthony A.; Wildy, Peter

1979-01-01

Systemic treatment of mice with the nucleoside analog 9-(2-hydroxyethoxymethyl)guanine (acycloguanosine [aciclovir]) was found to be highly effective against acute type 1 herpes simplex virus infection of the pinna. The drug ablated clinical signs and reduced virus replication both in tissue local to the inoculation site and within the nervous system. Provided that moderate-sized virus inocula were used, acycloguanosine treatment reduced or prevented the establishment of a latent infection in the dorsal root ganglia relating to the sensory nerve supply of the ear. However, although it aborted artificially produced infections in dorsal root ganglia, acycloguanosine was found not to be effective against the latent infection once established. This finding strongly indicated that latent herpes simplex virus in mice can exist in a nonreplicating form. PMID:464587

Automatic sleep classification using a data-driven topic model reveals latent sleep states

DEFF Research Database (Denmark)

Koch, Henriette; Christensen, Julie Anja Engelhard; Frandsen, Rune

2014-01-01

Latent Dirichlet Allocation. Model application was tested on control subjects and patients with periodic leg movements (PLM) representing a non-neurodegenerative group, and patients with idiopathic REM sleep behavior disorder (iRBD) and Parkinson's Disease (PD) representing a neurodegenerative group......Background: The golden standard for sleep classification uses manual scoring of polysomnography despite points of criticism such as oversimplification, low inter-rater reliability and the standard being designed on young and healthy subjects. New method: To meet the criticism and reveal the latent...... sleep states, this study developed a general and automatic sleep classifier using a data-driven approach. Spectral EEG and EOG measures and eye correlation in 1 s windows were calculated and each sleep epoch was expressed as a mixture of probabilities of latent sleep states by using the topic model...

Failure of PCR to Detect Treponema pallidum ssp. pertenue DNA in Blood in Latent Yaws.

Directory of Open Access Journals (Sweden)

Michael Marks

Full Text Available Yaws, caused by Treponema pallidum ssp. pertenue, is a neglected tropical disease closely related to venereal syphilis and is targeted for eradication by 2020. Latent yaws represents a diagnostic challenge, and current tools cannot adequately distinguish between individuals with true latent infection and individuals who are serofast following successful treatment. PCR on blood has previously been shown to detect T. pallidum DNA in patients with syphilis, suggesting that this approach may be of value in yaws. We performed real-time PCR for Treponema pallidum ssp. pertenue on blood samples from 140 children with positive T. pallidum Particle Agglutination (TPPA and Rapid Plasma Reagin (RPR tests and 7 controls (negative serology, all collected as part of a prospective study of yaws in the Solomon Islands. All samples were also tested by a nested PCR for T. pallidum. 12 patients had clinical evidence of active yaws whilst 128 were considered to have latent yaws. 43 children had high titre rapid plasma reagins (RPRs of ≥1:32. PCR testing with both assays gave negative results in all cases. It is possible that the failure to detect T. pallidum ssp. pertenue in blood reflects lower loads of organism in latent yaws compared to those in latent infection with T. pallidum ssp. pertenue, and/or a lower propensity for haematogenous dissemination in yaws than in syphilis. As the goal of the yaws control programme is eradication, a tool that can differentiate true latent infection from individuals who are serofast would be of value; however, PCR of blood is not that tool.

Failure of PCR to Detect Treponema pallidum ssp. pertenue DNA in Blood in Latent Yaws.

Science.gov (United States)

Marks, Michael; Katz, Samantha; Chi, Kai-Hua; Vahi, Ventis; Sun, Yongcheng; Mabey, David C; Solomon, Anthony W; Chen, Cheng Y; Pillay, Allan

2015-01-01

Yaws, caused by Treponema pallidum ssp. pertenue, is a neglected tropical disease closely related to venereal syphilis and is targeted for eradication by 2020. Latent yaws represents a diagnostic challenge, and current tools cannot adequately distinguish between individuals with true latent infection and individuals who are serofast following successful treatment. PCR on blood has previously been shown to detect T. pallidum DNA in patients with syphilis, suggesting that this approach may be of value in yaws. We performed real-time PCR for Treponema pallidum ssp. pertenue on blood samples from 140 children with positive T. pallidum Particle Agglutination (TPPA) and Rapid Plasma Reagin (RPR) tests and 7 controls (negative serology), all collected as part of a prospective study of yaws in the Solomon Islands. All samples were also tested by a nested PCR for T. pallidum. 12 patients had clinical evidence of active yaws whilst 128 were considered to have latent yaws. 43 children had high titre rapid plasma reagins (RPRs) of ≥1:32. PCR testing with both assays gave negative results in all cases. It is possible that the failure to detect T. pallidum ssp. pertenue in blood reflects lower loads of organism in latent yaws compared to those in latent infection with T. pallidum ssp. pertenue, and/or a lower propensity for haematogenous dissemination in yaws than in syphilis. As the goal of the yaws control programme is eradication, a tool that can differentiate true latent infection from individuals who are serofast would be of value; however, PCR of blood is not that tool.

The epigenetic landscape of latent Kaposi sarcoma-associated herpesvirus genomes.

Directory of Open Access Journals (Sweden)

Thomas Günther

Full Text Available Herpesvirus latency is generally thought to be governed by epigenetic modifications, but the dynamics of viral chromatin at early timepoints of latent infection are poorly understood. Here, we report a comprehensive spatial and temporal analysis of DNA methylation and histone modifications during latent infection with Kaposi Sarcoma-associated herpesvirus (KSHV, the etiologic agent of Kaposi Sarcoma and primary effusion lymphoma (PEL. By use of high resolution tiling microarrays in conjunction with immunoprecipitation of methylated DNA (MeDIP or modified histones (chromatin IP, ChIP, our study revealed highly distinct landscapes of epigenetic modifications associated with latent KSHV infection in several tumor-derived cell lines as well as de novo infected endothelial cells. We find that KSHV genomes are subject to profound methylation at CpG dinucleotides, leading to the establishment of characteristic global DNA methylation patterns. However, such patterns evolve slowly and thus are unlikely to control early latency. In contrast, we observed that latency-specific histone modification patterns were rapidly established upon a de novo infection. Our analysis furthermore demonstrates that such patterns are not characterized by the absence of activating histone modifications, as H3K9/K14-ac and H3K4-me3 marks were prominently detected at several loci, including the promoter of the lytic cycle transactivator Rta. While these regions were furthermore largely devoid of the constitutive heterochromatin marker H3K9-me3, we observed rapid and widespread deposition of H3K27-me3 across latent KSHV genomes, a bivalent modification which is able to repress transcription in spite of the simultaneous presence of activating marks. Our findings suggest that the modification patterns identified here induce a poised state of repression during viral latency, which can be rapidly reversed once the lytic cycle is induced.

High-temperature thermocline TES combining sensible and latent heat - CFD modeling and experimental validation

Science.gov (United States)

Zavattoni, Simone A.; Geissbühler, Lukas; Barbato, Maurizio C.; Zanganeh, Giw; Haselbacher, Andreas; Steinfeld, Aldo

2017-06-01

The concept of combined sensible/latent heat thermal energy storage (TES) has been exploited to mitigate an intrinsic thermocline TES systems drawback of heat transfer fluid outflow temperature reduction during discharging. In this study, the combined sensible/latent TES prototype under investigation is constituted by a packed bed of rocks and a small amount of encapsulated phase change material (AlSi12) as sensible heat and latent heat sections respectively. The thermo-fluid dynamics behavior of the combined TES prototype was analyzed by means of a computational fluid dynamics approach. Due to the small value of the characteristic vessel-to-particles diameter ratio, the effect of radial void-fraction variation, also known as channeling, was accounted for. Both the sensible and the latent heat sections of the storage were modeled as porous media under the assumption of local thermal non-equilibrium (LTNE). The commercial code ANSYS Fluent 15.0 was used to solve the model's constitutive conservation and transport equations obtaining a fairly good agreement with reference experimental measurements.

Prognostic factors for tuberculosis development in children with latent tuberculous infection

Directory of Open Access Journals (Sweden)

N. V. Korneva

2016-01-01

Full Text Available Goal of the study: to detect specific immune response in children with latent tuberculous infection and define factors to forecast the development of the active disease in this group.Materials and methods. The changes in clinical, X-ray and immunological data were analyzed in 127 children when latent tuberculous infection was diagnosed and after 12 months of follow-up. The number of immunological tests was done for evaluation of humoral and cellular immunity in those suffering from latent tuberculous infection and active disease.Results. The obtained results showed high negative prognostic relevance of exposure to tuberculosis, concurrent disease, refusal to have preventive treatment and low efficiency of short-course preventive treatment, specific features of humoral and cellular immunity were defined which could be used as additional forecasting criteria for active tuberculosis development in children with latent tuberculous infection. 

Reactivation of latent HIV-1 by new semi-synthetic ingenol esters

Energy Technology Data Exchange (ETDEWEB)

Pandeló José, Diego [Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902 (Brazil); Bartholomeeusen, Koen [Department of Medicine, Microbiology and Immunology, University of California at San Francisco, San Francisco, CA 94143-0703 (United States); Delveccio da Cunha, Rodrigo; Abreu, Celina Monteiro [Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902 (Brazil); Glinski, Jan [PlantaAnalytica LLC, Danbury, CT 06810 (United States); Barbizan Ferreira da Costa, Thais; Bacchi Rabay, Ana Flávia Mello; Pianowski Filho, Luiz Francisco [Kyolab Laboratories, Valinhos, São Paulo 13273-105 (Brazil); Dudycz, Lech W. [Lex Company Research Laboratories, Shirley 01464, MA (United States); Ranga, Udaykumar [Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru 560064 (India); Peterlin, Boris Matija [Department of Medicine, Microbiology and Immunology, University of California at San Francisco, San Francisco, CA 94143-0703 (United States); Pianowski, Luiz Francisco [Kyolab Laboratories, Valinhos, São Paulo 13273-105 (Brazil); Tanuri, Amilcar [Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902 (Brazil); Aguiar, Renato Santana, E-mail: santana@biologia.ufrj.br [Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902 (Brazil)

2014-08-15

The ability of HIV to establish long-lived latent infection is mainly due to transcriptional silencing of viral genome in resting memory T lymphocytes. Here, we show that new semi-synthetic ingenol esters reactivate latent HIV reservoirs. Amongst the tested compounds, 3-caproyl-ingenol (ING B) was more potent in reactivating latent HIV than known activators such as SAHA, ingenol 3,20-dibenzoate, TNF-α, PMA and HMBA. ING B activated PKC isoforms followed by NF-κB nuclear translocation. As virus reactivation is dependent on intact NF-κB binding sites in the LTR promoter region ING B, we have shown that. ING B was able to reactivate virus transcription in primary HIV-infected resting cells up to 12 fold and up to 25 fold in combination with SAHA. Additionally, ING B promoted up-regulation of P-TEFb subunits CDK9/Cyclin T1. The role of ING B on promoting both transcription initiation and elongation makes this compound a strong candidate for an anti-HIV latency drug combined with suppressive HAART. - Highlights: • 3-caproyl-ingenol (ING B) reactivates latent HIV better than SAHA, ingenol 3,20-dibenzoate, TNF-α, PMA and HMBA. • ING B promotes PKC activation and NF-kB translocation to the nucleus. • ING B activates virus transcription of B and non-B subtypes of HIV-1. • ING B activates HIV transcription in infected primary resting CD4+ T cells. • ING B induces higher levels of P-TEFb components in human primary cells.

Detecting New Words from Chinese Text Using Latent Semi-CRF Models

Science.gov (United States)

Sun, Xiao; Huang, Degen; Ren, Fuji

Chinese new words and their part-of-speech (POS) are particularly problematic in Chinese natural language processing. With the fast development of internet and information technology, it is impossible to get a complete system dictionary for Chinese natural language processing, as new words out of the basic system dictionary are always being created. A latent semi-CRF model, which combines the strengths of LDCRF (Latent-Dynamic Conditional Random Field) and semi-CRF, is proposed to detect the new words together with their POS synchronously regardless of the types of the new words from the Chinese text without being pre-segmented. Unlike the original semi-CRF, the LDCRF is applied to generate the candidate entities for training and testing the latent semi-CRF, which accelerates the training speed and decreases the computation cost. The complexity of the latent semi-CRF could be further adjusted by tuning the number of hidden variables in LDCRF and the number of the candidate entities from the Nbest outputs of the LDCRF. A new-words-generating framework is proposed for model training and testing, under which the definitions and distributions of the new words conform to the ones existing in real text. Specific features called “Global Fragment Information” for new word detection and POS tagging are adopted in the model training and testing. The experimental results show that the proposed method is capable of detecting even low frequency new words together with their POS tags. The proposed model is found to be performing competitively with the state-of-the-art models presented.

Characterization of Chemokine Receptor Utilization of Viruses in the Latent Reservoir for Human Immunodeficiency Virus Type 1

Science.gov (United States)

Pierson, Theodore; Hoffman, Trevor L.; Blankson, Joel; Finzi, Diana; Chadwick, Karen; Margolick, Joseph B.; Buck, Christopher; Siliciano, Janet D.; Doms, Robert W.; Siliciano, Robert F.

2000-01-01

Latently infected resting CD4+ T cells provide a long-term reservoir for human immunodeficiency virus type 1 (HIV-1) and are likely to represent the major barrier to virus eradication in patients on combination antiretroviral therapy. The mechanisms by which viruses enter the latent reservoir and the nature of the chemokine receptors involved have not been determined. To evaluate the phenotype of the virus in this compartment with respect to chemokine receptor utilization, full-length HIV-1 env genes were cloned from latently infected cells and assayed functionally. We demonstrate that the majority of the viruses in the latent reservoir utilize CCR5 during entry, although utilization of several other receptors, including CXCR4, was observed. No alternative coreceptors were shown to be involved in a systematic fashion. Although R5 viruses are present in the latent reservoir, CCR5 was not expressed at high levels on resting CD4+ T cells. To understand the mechanism by which R5 viruses enter latent reservoir, the ability of an R5 virus, HIV-1 Ba-L, to infect highly purified resting CD4+ T lymphocytes from uninfected donors was evaluated. Entry of Ba-L could be observed when virus was applied at a multiplicity approaching 1. However, infection was limited to a subset of cells expressing low levels of CCR5 and markers of immunologic memory. Naive cells could not be infected by an R5 virus even when challenged with a large inoculum. Direct cell fractionation studies showed that latent virus is present predominantly in resting memory cells but also at lower levels in resting naive cells. Taken together, these findings provide support for the hypothesis that the direct infection of naive T cells is not the major mechanism by which the latent infection of resting T cells is established. PMID:10933689

Latent log-linear models for handwritten digit classification.

Science.gov (United States)

Deselaers, Thomas; Gass, Tobias; Heigold, Georg; Ney, Hermann

2012-06-01

We present latent log-linear models, an extension of log-linear models incorporating latent variables, and we propose two applications thereof: log-linear mixture models and image deformation-aware log-linear models. The resulting models are fully discriminative, can be trained efficiently, and the model complexity can be controlled. Log-linear mixture models offer additional flexibility within the log-linear modeling framework. Unlike previous approaches, the image deformation-aware model directly considers image deformations and allows for a discriminative training of the deformation parameters. Both are trained using alternating optimization. For certain variants, convergence to a stationary point is guaranteed and, in practice, even variants without this guarantee converge and find models that perform well. We tune the methods on the USPS data set and evaluate on the MNIST data set, demonstrating the generalization capabilities of our proposed models. Our models, although using significantly fewer parameters, are able to obtain competitive results with models proposed in the literature.

Measuring behaviours for escaping from house fires: use of latent variable models to summarise multiple behaviours.

Science.gov (United States)

Ploubidis, G B; Edwards, P; Kendrick, D

2015-12-15

This paper reports the development and testing of a construct measuring parental fire safety behaviours for planning escape from a house fire. Latent variable modelling of data on parental-reported fire safety behaviours and plans for escaping from a house fire and multivariable logistic regression to quantify the association between groups defined by the latent variable modelling and parental-report of having a plan for escaping from a house fire. Data comes from 1112 participants in a cluster randomised controlled trial set in children's centres in 4 study centres in the UK. A two class model provided the best fit to the data, combining responses to five fire safety planning behaviours. The first group ('more behaviours for escaping from a house fire') comprised 86% of participants who were most likely to have a torch, be aware of how their smoke alarm sounds, to have external door and window keys accessible, and exits clear. The second group ('fewer behaviours for escaping from a house fire') comprised 14% of participants who were less likely to report these five behaviours. After adjusting for potential confounders, participants allocated to the 'more behaviours for escaping from a house fire group were 2.5 times more likely to report having an escape plan (OR 2.48; 95% CI 1.59-3.86) than those in the "fewer behaviours for escaping from a house fire" group. Multiple fire safety behaviour questions can be combined into a single binary summary measure of fire safety behaviours for escaping from a house fire. Our findings will be useful to future studies wishing to use a single measure of fire safety planning behaviour as measures of outcome or exposure. NCT 01452191. Date of registration 13/10/2011.

New Treatment Regimen for Latent Tuberculosis Infection

Centers for Disease Control (CDC) Podcasts

2012-03-15

In this podcast, Dr. Kenneth Castro, Director of the Division of Tuberculosis Elimination, discusses the December 9, 2011 CDC guidelines for the use of a new regimen for the treatment of persons with latent tuberculosis infection.  Created: 3/15/2012 by National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP).   Date Released: 3/15/2012.

Risk-taking behaviors and subgrouping of suicide in Iran: A latent class analysis of national registries data.

Science.gov (United States)

Hajebi, Ahmad; Abbasi-Ghahramanloo, Abbas; Hashemian, Seyed Sepehr; Khatibi, Seyed Reza; Ghasemzade, Masomeh; Khodadost, Mahmoud

2017-09-01

Suicide is one the most important public health problem which is rapidly growing concerns. The aim of this study was to subgroup suicide using LCA method. This cross-sectional study was conducted in Iran based on 66990 records registered in Ministry of Health in 2014. A case report questionnaire in the form of software was used for case registries. Latent class analysis was used to achieve the research objectives. Four latent classes were identified; (a) Non-lethal attempters without a history of psychiatric disorders, (b) Non-lethal attempters with a history of psychiatric disorders, (c) Lethal attempters without a history of psychiatric disorders, (d) Lethal attempters with a history of psychiatric disorders. The probability of completed/an achieved suicide is high in lethal attempter classes. Being male increases the risk of inclusion in lethal attempters' classes (OR = 4.93). Also, being single (OR = 1.16), having an age lower than 25 years (OR = 1.14) and being a rural citizen (OR = 2.36) associate with lethal attempters classes. The males tend to use more violent methods and have more completed suicide. Majority of the individuals are non-lethal attempters who need to be addressed by implementing preventive interventions and mental support provision. Copyright © 2017. Published by Elsevier B.V.

Getting the "Kill" into "Shock and Kill": Strategies to Eliminate Latent HIV.

Science.gov (United States)

Kim, Youry; Anderson, Jenny L; Lewin, Sharon R

2018-01-10

Despite the success of antiretroviral therapy (ART), there is currently no HIV cure and treatment is life long. HIV persists during ART due to long-lived and proliferating latently infected CD4+ T cells. One strategy to eliminate latency is to activate virus production using latency reversing agents (LRAs) with the goal of triggering cell death through virus-induced cytolysis or immune-mediated clearance. However, multiple studies have demonstrated that activation of viral transcription alone is insufficient to induce cell death and some LRAs may counteract cell death by promoting cell survival. Here, we review new approaches to induce death of latently infected cells through apoptosis and inhibition of pathways critical for cell survival, which are often hijacked by HIV proteins. Given advances in the commercial development of compounds that induce apoptosis in cancer chemotherapy, these agents could move rapidly into clinical trials, either alone or in combination with LRAs, to eliminate latent HIV infection. Copyright © 2017 Elsevier Inc. All rights reserved.

Expression of the mucus adhesion genes Mub and MapA, adhesion-like factor EF-Tu and bacteriocin gene plaA of Lactobacillus plantarum 423, monitored with real-time PCR.

Science.gov (United States)

Ramiah, K; van Reenen, C A; Dicks, L M T

2007-05-30

Expression of the mucus adhesion genes Mub and MapA, adhesion-like factor EF-Tu and bacteriocin gene plaA by Lactobacillus plantarum 423, grown in the presence of bile, pancreatin and at low pH, was studied by real-time PCR. Mub, MapA and EF-Tu were up-regulated in the presence of mucus, proportional to increasing concentrations. Expression of MapA was up-regulated in the presence of 3.0 g/l bile and 3.0 g/l pancreatin at pH 6.5. Similar results were recorded in the presence of 10.0 g/l bile and 10.0 g/l pancreatin at pH 6.5. Expression of Mub was down-regulated in the presence of bile and pancreatin, whilst the expression of EF-Tu and plaA remained unchanged. Expression of Mub and MapA remained unchanged at pH 4.0, whilst expression of EF-Tu and plaA were up-regulated. Expression of MapA was down-regulated in the presence of 1.0 g/l l-cysteine HCl, suggesting that the gene is regulated by transcription attenuation that involves cysteine.

How to get rid of W: a latent variables approach to modelling spatially lagged variables

NARCIS (Netherlands)

Folmer, H.; Oud, J.

2008-01-01

In this paper we propose a structural equation model (SEM) with latent variables to model spatial dependence. Rather than using the spatial weights matrix W, we propose to use latent variables to represent spatial dependence and spillover effects, of which the observed spatially lagged variables are

How to get rid of W : a latent variables approach to modelling spatially lagged variables

NARCIS (Netherlands)

Folmer, Henk; Oud, Johan

2008-01-01

In this paper we propose a structural equation model (SEM) with latent variables to model spatial dependence. Rather than using the spatial weights matrix W, we propose to use latent variables to represent spatial dependence and spillover effects, of which the observed spatially lagged variables are

The Latent Structure of Secure Base Script Knowledge

Science.gov (United States)

Waters, Theodore E. A.; Fraley, R. Chris; Groh, Ashley M.; Steele, Ryan D.; Vaughn, Brian E.; Bost, Kelly K.; Veríssimo, Manuela; Coppola, Gabrielle; Roisman, Glenn I.

2015-01-01

There is increasing evidence that attachment representations abstracted from childhood experiences with primary caregivers are organized as a cognitive script describing secure base use and support (i.e., the "secure base script"). To date, however, the latent structure of secure base script knowledge has gone unexamined--this despite…

Latent Partially Ordered Classification Models and Normal Mixtures

Science.gov (United States)

Tatsuoka, Curtis; Varadi, Ferenc; Jaeger, Judith

2013-01-01

Latent partially ordered sets (posets) can be employed in modeling cognitive functioning, such as in the analysis of neuropsychological (NP) and educational test data. Posets are cognitively diagnostic in the sense that classification states in these models are associated with detailed profiles of cognitive functioning. These profiles allow for…

A latent transition model of the effects of a teen dating violence prevention initiative.

Science.gov (United States)

Williams, Jason; Miller, Shari; Cutbush, Stacey; Gibbs, Deborah; Clinton-Sherrod, Monique; Jones, Sarah

2015-02-01

Patterns of physical and psychological teen dating violence (TDV) perpetration, victimization, and related behaviors were examined with data from the evaluation of the Start Strong: Building Healthy Teen Relationships initiative, a dating violence primary prevention program targeting middle school students. Latent class and latent transition models were used to estimate distinct patterns of TDV and related behaviors of bullying and sexual harassment in seventh grade students at baseline and to estimate transition probabilities from one pattern of behavior to another at the 1-year follow-up. Intervention effects were estimated by conditioning transitions on exposure to Start Strong. Latent class analyses suggested four classes best captured patterns of these interrelated behaviors. Classes were characterized by elevated perpetration and victimization on most behaviors (the multiproblem class), bullying perpetration/victimization and sexual harassment victimization (the bully-harassment victimization class), bullying perpetration/victimization and psychological TDV victimization (bully-psychological victimization), and experience of bully victimization (bully victimization). Latent transition models indicated greater stability of class membership in the comparison group. Intervention students were less likely to transition to the most problematic pattern and more likely to transition to the least problem class. Although Start Strong has not been found to significantly change TDV, alternative evaluation models may find important differences. Latent transition analysis models suggest positive intervention impact, especially for the transitions at the most and the least positive end of the spectrum. Copyright © 2015. Published by Elsevier Inc.

Reactivation of Latent Epstein-Barr Virus; A Comparison After Gamma Rays and Proton Treatment

Science.gov (United States)

Mehta, Satish K.; Plante, Ianik; Bloom, David C.; Stowe, Raymond; Renner, Ashlie; Wu, Honglu; Crucian, Brian; Pierson, Duane L.

2017-01-01

Among different unique stressors astronauts are exposed to during spaceflight, cosmic radiation constitutes an important one that leads to various health effects. In particular, space radiation may contribute to decreased immunity, which has been observed in astronauts during short and long duration missions, as evidenced by several changes in cellular immunity and plasma cytokines levels. Reactivation of latent herpes viruses, either directly from radiation or resulting from perturbation in the immune system, is also observed in astronauts. While EBV is one of the eight human herpes viruses known to infect more than 90% human adults and stays latent for the life of the host without normally causing adverse effects of reactivation, increased reactivation in astronauts is well-documented, though the mechanism of this increase is not understood. In this work, we have studied the effect of two different types of radiations, Cs-137 gamma and 150-MeV proton on the reactivation rates of the Epstein - Barr virus (EBV) in vitro in EBV latent cell lines at doses of 0.1, 0.5, 1.0 and 2.0 Gy. While we find that both types of radiations reactivated latent EBV in vitro, we observe that at equivalent doses, early response is stronger for protons but with time, the reactivation induced by gamma rays is more persistent. These differences between the protons and gamma rays curves in latent virus reactivation challenge the common paradigm that protons and gamma rays have similar biological effects.

Mycobacteria-specific cytokine responses as correlates of treatment response in active and latent tuberculosis.

Science.gov (United States)

Clifford, Vanessa; Tebruegge, Marc; Zufferey, Christel; Germano, Susie; Forbes, Ben; Cosentino, Lucy; McBryde, Emma; Eisen, Damon; Robins-Browne, Roy; Street, Alan; Denholm, Justin; Curtis, Nigel

2017-08-01

A biomarker indicating successful tuberculosis (TB) therapy would assist in determining appropriate length of treatment. This study aimed to determine changes in mycobacteria-specific antigen-induced cytokine biomarkers in patients receiving therapy for latent or active TB, to identify biomarkers potentially correlating with treatment success. A total of 33 adults with active TB and 36 with latent TB were followed longitudinally over therapy. Whole blood stimulation assays using mycobacteria-specific antigens (CFP-10, ESAT-6, PPD) were done on samples obtained at 0, 1, 3, 6 and 9 months. Cytokine responses (IFN-γ, IL-1ra, IL-2, IL-10, IL-13, IP-10, MIP-1β, and TNF-α) in supernatants were measured by Luminex xMAP immunoassay. In active TB cases, median IL-1ra (with CFP-10 and with PPD stimulation), IP-10 (CFP-10, ESAT-6), MIP-1β (ESAT-6, PPD), and TNF-α (ESAT-6) responses declined significantly over the course of therapy. In latent TB cases, median IL-1ra (CFP-10, ESAT-6, PPD), IL-2 (CFP-10, ESAT-6), and IP-10 (CFP-10, ESAT-6) responses declined significantly. Mycobacteria-specific cytokine responses change significantly over the course of therapy, and their kinetics in active TB differ from those observed in latent TB. In particular, mycobacteria-specific IL-1ra responses are potential correlates of successful therapy in both active and latent TB. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Gestão do processo de design de arquitetura efêmera em museus

OpenAIRE

Veiga, Ana Cecilia Nascimento Rocha; Andery, Paulo Roberto Pereira

2014-01-01

A gestão de empreendimentos de museus e espaços museográficos têm crescido em complexidade, particularmente na sua fase de concepção. Contribui para isso o reduzido ciclo de vida dos empreendimentos, a arquitetura efêmera, que supõe pouco tempo para projetação, execução e montagem. Soma-se a mudança de significado que os espaços museográficos tiveram em anos recentes, com a interação entre acervo, ambiente construído e público, gerando um briefing mais dinâmico e complexo. Nesse contexto, o p...

Forensic applications of infrared imaging for the detection and recording of latent evidence.

Science.gov (United States)

Lin, Apollo Chun-Yen; Hsieh, Hsing-Mei; Tsai, Li-Chin; Linacre, Adrian; Lee, James Chun-I

2007-09-01

We report on a simple method to record infrared (IR) reflected images in a forensic science context. Light sources using ultraviolet light have been used previously in the detection of latent prints, but the use of infrared light has been subjected to less investigation. IR light sources were used to search for latent evidence and the images were captured by either video or using a digital camera with a CCD array sensitive to IR wavelength. Bloodstains invisible to the eye, inks, tire prints, gunshot residue, and charred document on dark background are selected as typical matters that may be identified during a forensic investigation. All the evidence types could be detected and identified using a range of photographic techniques. In this study, a one in eight times dilution of blood could be detected on 10 different samples of black cloth. When using 81 black writing inks, the observation rates were 95%, 88% and 42% for permanent markers, fountain pens and ball-point pens, respectively, on the three kinds of dark cloth. The black particles of gunshot residue scattering around the entrance hole under IR light were still observed at a distance of 60 cm from three different shooting ranges. A requirement of IR reflectivity is that there is a contrast between the latent evidence and the background. In the absence of this contrast no latent image will be detected, which is similar to all light sources. The use of a video camera allows the recording of images either at a scene or in the laboratory. This report highlights and demonstrates the robustness of IR to detect and record the presence of latent evidence.

Altered intrinsic functional connectivity in the latent period of epileptogenesis in a temporal lobe epilepsy model.

Science.gov (United States)

Lee, Hyoin; Jung, Seungmoon; Lee, Peter; Jeong, Yong

2017-10-01

The latent period, a seizure-free phase, is the duration between brain injury and the onset of spontaneous recurrent seizures (SRSs) during epileptogenesis. The latent period is thought to involve several progressive pathophysiological events that lead to the evolution of the chronic epilepsy phase. Hence, it is vital to investigate the changes in the latent period during epileptogenesis in order to better understand temporal lobe epilepsy (TLE), and to achieve early diagnosis and appropriate management of the condition. Accordingly, recent studies with patients with TLE using resting-state functional magnetic resonance imaging (rs-fMRI) have reported that alterations of resting-state functional connectivity (rsFC) during the chronic period are associated with some clinical manifestations, including learning and memory impairments, emotional instability, and social behavior deficits, in addition to repetitive seizure episodes. In contrast, the changes in the intrinsic rsFC during epileptogenesis, particularly during the latent period, remain unclear. In this study, we investigated the alterations in intrinsic rsFC during the latent and chronic periods in a pilocarpine-induced TLE mouse model using intrinsic optical signal imaging (IOSI). This technique can monitor the changes in the local hemoglobin concentration according to neuronal activity and can help investigate large-scale brain intrinsic networks. After seeding on the anatomical regions of interest (ROIs) and calculating the correlation coefficients between each ROI, we established and compared functional correlation matrices and functional connectivity maps during the latent and chronic periods of epilepsy. We found a decrease in the interhemispheric rsFC at the frontal and temporal regions during both the latent and chronic periods. Furthermore, a significant decrease in the interhemispheric rsFC was observed in the somatosensory area during the chronic period. Changes in network configurations during

A Modified Electrostatic Adsorption Apparatus for Latent Fingerprint Development on Unfired Cartridge Cases.

Science.gov (United States)

Xu, Jingyang; Zhang, Ziyuan; Zheng, Xiaochun; Bond, John W

2017-05-01

Visualization of latent fingerprints on metallic surfaces by the method of applying electrostatic charging and adsorption is considered as a promising chemical-free method, which has the merit of nondestruction, and is considered to be effective for some difficult situations such as aged fingerprint deposits or those exposed to environmental extremes. In fact, a portable electrostatic generator can be easily accessible in a local forensic technology laboratory, which is already widely used in the visualization of footwear impressions. In this study, a modified version of this electrostatic apparatus is proposed for latent fingerprint development and has shown great potential in visualizing fingerprints on metallic surfaces such as cartridge cases. Results indicate that this experimental arrangement can successfully develop aged latent fingerprints on metal surfaces, and we demonstrate its effectiveness compared with existing conventional fingerprint recovery methods. © 2016 American Academy of Forensic Sciences.

Does Attention-Deficit/Hyperactivity Disorder Have a Dimensional Latent Structure? A Taxometric Analysis

Science.gov (United States)

Marcus, David K.; Barry, Tammy D.

2010-01-01

An understanding of the latent structure of attention-deficit/hyperactivity disorder (ADHD) is essential for developing causal models of this disorder. Although some researchers have presumed that ADHD is dimensional and others have assumed that it is taxonic, there has been relatively little research directly examining the latent structure of ADHD. The authors conducted a set of taxometric analyses using data from the NICHD Study of Early Child Care and Youth Development (ns between 667–1078). The results revealed a dimensional latent structure across a variety of different analyses and sets of indicators, for inattention, hyperactivity/impulsivity, and ADHD. Furthermore, analyses of correlations with associated features indicated that dimensional models demonstrated stronger validity coefficients with these criterion measures than dichotomous models. These findings jibe with recent research on the genetic basis of ADHD and with contemporary models of ADHD. PMID:20973595

A Bayesian approach to estimate sensible and latent heat over vegetated land surface

Directory of Open Access Journals (Sweden)

C. van der Tol

2009-06-01

Full Text Available Sensible and latent heat fluxes are often calculated from bulk transfer equations combined with the energy balance. For spatial estimates of these fluxes, a combination of remotely sensed and standard meteorological data from weather stations is used. The success of this approach depends on the accuracy of the input data and on the accuracy of two variables in particular: aerodynamic and surface conductance. This paper presents a Bayesian approach to improve estimates of sensible and latent heat fluxes by using a priori estimates of aerodynamic and surface conductance alongside remote measurements of surface temperature. The method is validated for time series of half-hourly measurements in a fully grown maize field, a vineyard and a forest. It is shown that the Bayesian approach yields more accurate estimates of sensible and latent heat flux than traditional methods.

Does attention-deficit/hyperactivity disorder have a dimensional latent structure? A taxometric analysis.

Science.gov (United States)

Marcus, David K; Barry, Tammy D

2011-05-01

An understanding of the latent structure of attention-deficit/hyperactivity disorder (ADHD) is essential for developing causal models of this disorder. Although some researchers have presumed that ADHD is dimensional and others have assumed that it is taxonic, there has been relatively little research directly examining the latent structure of ADHD. The authors conducted a set of taxometric analyses using data from the NICHD Study of Early Child Care and Youth Development (ns between 667 and 1,078). The results revealed a dimensional latent structure across a variety of different analyses and sets of indicators for inattention, hyperactivity/impulsivity, and ADHD. Furthermore, analyses of correlations with associated features indicated that dimensional models demonstrated stronger validity coefficients with these criterion measures than dichotomous models. These findings jibe with recent research on the genetic basis of ADHD and with contemporary models of ADHD.

15N NMR relaxation studies of calcium-loaded parvalbumin show tight dynamics compared to those of other EF-hand proteins

DEFF Research Database (Denmark)

Baldellon, C; Alattia, J R; Strub, M P

1998-01-01

Dynamics of the rat alpha-parvalbumin calcium-loaded form have been determined by measurement of 15N nuclear relaxation using proton-detected heteronuclear NMR spectroscopy. The relaxation data were analyzed using spectral density functions and the Lipari-Szabo formalism. The major dynamic features...... for the rat alpha-parvalbumin calcium-loaded form are (1) the extreme rigidity of the helix-loop-helix EF-hand motifs and the linker segment connecting them, (2) the N and C termini of the protein being restricted in their mobility, (3) a conformational exchange occurring at the kink of helix D, and (4...... properties which are conserved in the EF-hand domains from different members of this superfamily: (1) a tendency toward higher mobility of NH vectors at relative position 2 in the Ca2+-binding loop, (2) a restricted mobility for the other residues in the binding loop, and (3) an overall rigidity...

Ef: Software for Nonrelativistic Beam Simulation by Particle-in-Cell Algorithm

Science.gov (United States)

Boytsov, A. Yu.; Bulychev, A. A.

2018-04-01

Understanding of particle dynamics is crucial in construction of electron guns, ion sources and other types of nonrelativistic beam devices. Apart from external guiding and focusing systems, a prominent role in evolution of such low-energy beams is played by particle-particle interaction. Numerical simulations taking into account these effects are typically accomplished by a well-known particle-in-cell method. In practice, for convenient work a simulation program should not only implement this method, but also support parallelization, provide integration with CAD systems and allow access to details of the simulation algorithm. To address the formulated requirements, development of a new open source code - Ef - has been started. It's current features and main functionality are presented. Comparison with several analytical models demonstrates good agreement between the numerical results and the theory. Further development plans are discussed.

Ef: Software for Nonrelativistic Beam Simulation by Particle-in-Cell Algorithm

Directory of Open Access Journals (Sweden)

Boytsov A. Yu.

2018-01-01

Full Text Available Understanding of particle dynamics is crucial in construction of electron guns, ion sources and other types of nonrelativistic beam devices. Apart from external guiding and focusing systems, a prominent role in evolution of such low-energy beams is played by particle-particle interaction. Numerical simulations taking into account these effects are typically accomplished by a well-known particle-in-cell method. In practice, for convenient work a simulation program should not only implement this method, but also support parallelization, provide integration with CAD systems and allow access to details of the simulation algorithm. To address the formulated requirements, development of a new open source code - Ef - has been started. It's current features and main functionality are presented. Comparison with several analytical models demonstrates good agreement between the numerical results and the theory. Further development plans are discussed.

Latent semantics as cognitive components

DEFF Research Database (Denmark)

Petersen, Michael Kai; Mørup, Morten; Hansen, Lars Kai

2010-01-01

Cognitive component analysis, defined as an unsupervised learning of features resembling human comprehension, suggests that the sensory structures we perceive might often be modeled by reducing dimensionality and treating objects in space and time as linear mixtures incorporating sparsity...... emotional responses can be encoded in words, we propose a simplified cognitive approach to model how we perceive media. Representing song lyrics in a vector space of reduced dimensionality using LSA, we combine bottom-up defined term distances with affective adjectives, that top-down constrain the latent......, which we suggest might function as cognitive components for perceiving the underlying structure in lyrics....

Experimental Examination of Bacteriophage Latent-Period Evolution as a Response to Bacterial Availability

OpenAIRE

Abedon, Stephen T.; Hyman, Paul; Thomas, Cameron

2003-01-01

For obligately lytic bacteriophage (phage) a trade-off exists between fecundity (burst size) and latent period (a component of generation time). This trade-off occurs because release of phage progeny from infected bacteria coincides with destruction of the machinery necessary to produce more phage progeny. Here we employ phage mutants to explore issues of phage latent-period evolution as a function of the density of phage-susceptible bacteria. Theory suggests that higher bacterial densities s...

Prevalence and risk factors of latent Tuberculosis among ...

African Journals Online (AJOL)

termine the risk factors of prevalent LTBI. We used a mixed effects binomial model with a logarithmic link function to estimate prevalence ratios (PR) for risk fac- tors of latent tuberculosis infection (LTBI). Ethical consideration. The study was approved by the Makerere University. School of Public Health–Higher Degrees and ...

Effect Of Prolonged Monocular Occlusion On Latent Nystagms

NARCIS (Netherlands)

H.J. Simonsz (Huib); G. Kommerell (Guntram)

1992-01-01

textabstractThe authors recorded nystagmus during seeing with one eye in eight patients with latent nystagmus (LN) before and after two or three days of prolonged occlusion of the better eye (POBE). Before POBE, the slow-phase speed of the nystagmus (SPS) was usually higher when the better eye was

Association of Stressful Life Events with Psychological Problems: A Large-Scale Community-Based Study Using Grouped Outcomes Latent Factor Regression with Latent Predictors

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Akbar Hassanzadeh

2017-01-01

Full Text Available Objective. The current study is aimed at investigating the association between stressful life events and psychological problems in a large sample of Iranian adults. Method. In a cross-sectional large-scale community-based study, 4763 Iranian adults, living in Isfahan, Iran, were investigated. Grouped outcomes latent factor regression on latent predictors was used for modeling the association of psychological problems (depression, anxiety, and psychological distress, measured by Hospital Anxiety and Depression Scale (HADS and General Health Questionnaire (GHQ-12, as the grouped outcomes, and stressful life events, measured by a self-administered stressful life events (SLEs questionnaire, as the latent predictors. Results. The results showed that the personal stressors domain has significant positive association with psychological distress (β=0.19, anxiety (β=0.25, depression (β=0.15, and their collective profile score (β=0.20, with greater associations in females (β=0.28 than in males (β=0.13 (all P<0.001. In addition, in the adjusted models, the regression coefficients for the association of social stressors domain and psychological problems profile score were 0.37, 0.35, and 0.46 in total sample, males, and females, respectively (P<0.001. Conclusion. Results of our study indicated that different stressors, particularly those socioeconomic related, have an effective impact on psychological problems. It is important to consider the social and cultural background of a population for managing the stressors as an effective approach for preventing and reducing the destructive burden of psychological problems.

Association of Stressful Life Events with Psychological Problems: A Large-Scale Community-Based Study Using Grouped Outcomes Latent Factor Regression with Latent Predictors

Science.gov (United States)

Hassanzadeh, Akbar; Heidari, Zahra; Hassanzadeh Keshteli, Ammar; Afshar, Hamid

2017-01-01

Objective The current study is aimed at investigating the association between stressful life events and psychological problems in a large sample of Iranian adults. Method In a cross-sectional large-scale community-based study, 4763 Iranian adults, living in Isfahan, Iran, were investigated. Grouped outcomes latent factor regression on latent predictors was used for modeling the association of psychological problems (depression, anxiety, and psychological distress), measured by Hospital Anxiety and Depression Scale (HADS) and General Health Questionnaire (GHQ-12), as the grouped outcomes, and stressful life events, measured by a self-administered stressful life events (SLEs) questionnaire, as the latent predictors. Results The results showed that the personal stressors domain has significant positive association with psychological distress (β = 0.19), anxiety (β = 0.25), depression (β = 0.15), and their collective profile score (β = 0.20), with greater associations in females (β = 0.28) than in males (β = 0.13) (all P < 0.001). In addition, in the adjusted models, the regression coefficients for the association of social stressors domain and psychological problems profile score were 0.37, 0.35, and 0.46 in total sample, males, and females, respectively (P < 0.001). Conclusion Results of our study indicated that different stressors, particularly those socioeconomic related, have an effective impact on psychological problems. It is important to consider the social and cultural background of a population for managing the stressors as an effective approach for preventing and reducing the destructive burden of psychological problems. PMID:29312459

Tissue-specific control of latent CMV reactivation by regulatory T cells.

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Maha Almanan

2017-08-01

Full Text Available Cytomegalovirus (CMV causes a persistent, lifelong infection. CMV persists in a latent state and undergoes intermittent subclinical viral reactivation that is quelled by ongoing T cell responses. While T cells are critical to maintain control of infection, the immunological factors that promote CMV persistence remain unclear. Here, we investigated the role of regulatory T cells (Treg in a mouse model of latent CMV infection using Foxp3-diphtheria toxin receptor (Foxp3-DTR mice. Eight months after infection, MCMV had established latency in the spleen, salivary gland, lung, and pancreas, which was accompanied by an increased frequency of Treg. Administration of diphtheria toxin (DT after establishment of latency efficiently depleted Treg and drove a significant increase in the numbers of functional MCMV-specific CD4+ and CD8+ T cells. Strikingly, Treg depletion decreased the number of animals with reactivatable latent MCMV in the spleen. Unexpectedly, in the same animals, ablation of Treg drove a significant increase in viral reactivation in the salivary gland that was accompanied with augmented local IL-10 production by Foxp3-CD4+T cells. Further, neutralization of IL-10 after Treg depletion significantly decreased viral load in the salivary gland. Combined, these data show that Treg have divergent control of MCMV infection depending upon the tissue. In the spleen, Treg antagonize CD8+ effector function and promote viral persistence while in the salivary gland Treg prevent IL-10 production and limit viral reactivation and replication. These data provide new insights into the organ-specific roles of Treg in controlling the reactivation of latent MCMV infection.

Short-term memory development: differences in serial position curves between age groups and latent classes.

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Koppenol-Gonzalez, Gabriela V; Bouwmeester, Samantha; Vermunt, Jeroen K

2014-10-01

In studies on the development of cognitive processes, children are often grouped based on their ages before analyzing the data. After the analysis, the differences between age groups are interpreted as developmental differences. We argue that this approach is problematic because the variance in cognitive performance within an age group is considered to be measurement error. However, if a part of this variance is systematic, it can provide very useful information about the cognitive processes used by some children of a certain age but not others. In the current study, we presented 210 children aged 5 to 12 years with serial order short-term memory tasks. First we analyze our data according to the approach using age groups, and then we apply latent class analysis to form latent classes of children based on their performance instead of their ages. We display the results of the age groups and the latent classes in terms of serial position curves, and we discuss the differences in results. Our findings show that there are considerable differences in performance between the age groups and the latent classes. We interpret our findings as indicating that the latent class analysis yielded a much more meaningful way of grouping children in terms of cognitive processes than the a priori grouping of children based on their ages. Copyright © 2014 Elsevier Inc. All rights reserved.