Search results for "quantitative"
showing 10 items of 2409 documents
Electoral opportunism and water pricing with incomplete transfer of control rights
2020
One of the forms of intervention in public services that lie beyond market forces is price control. While such regulation is justified by the need to achieve social goals, empirical evidence has sh...
Political patterning of urban namescapes and post-socialist toponymic change: A quantitative analysis of three Romanian cities
2020
Abstract Critical scholars of place-name studies have compellingly demonstrated that significant transformations in a society's namescape follow suit major power shifts and regime changes. However, despite the wealth of particular case studies existing in the literature, scarce efforts have been made to examine street name changes in a comparative framework using statistical modeling techniques of multivariate analysis. This paper aims to overcome these shortcomings by developing a comparative approach to analyzing post-socialist street-naming transformations in three Romanian cities from Transylvania (Brașov, Cluj-Napoca, and Sibiu). Based on comprehensive data collected from multiple sour…
Interindividual Differences in Treatment Effects based on Structural Equation Models with Latent Variables: An EffectLiteR Tutorial
2019
The investigation of interindividual differences in the effects of a treatment is challenging, because many constructs-of-interest in psychological research such as depression or anxiety are latent variables and modeling heterogeneity in treatment effects requires interactions and potentially nonlinear relationships. In this paper, we present a tutorial of the EffectLiteR approach (Mayer, Dietzfelbinger, Rosseel, & Steyer, 2016) that allows for estimating individual treatment effects based on latent variable models. We describe step by step how to apply the approach using the EffectLiteR software package with data from the multicenter randomized controlled trial of the Social Phobia…
Rīgas iedzīvotāju attieksme pret ārzemnieku apmešanos uz pastāvīgu dzīvi Latvijā
2018
Bakalaura darba nosaukums ir “Rīgas iedzīvotāju attieksme pret ārzemnieku apmešanos uz pastāvīgu dzīvi Latvijā”. Darba mērķis bija noskaidrot kāda ir Rīgas iedzīvotāju attieksme pret ārzemnieku apmešanos uz pastāvīgu dzīvi Latvijā. Pētījuma uzdevumi bija noskaidrot, 1) kas ietekmē attieksmes veidošanos pret ārzemnieku integrēšanos Latvijā, 2) kāda ir Rīgas iedzīvotāju attieksme pret ārzemniekiem Latvijā, 3) kas veicina Rīgas iedzīvotāju toleranci pret Latvijā dzīvojošajiem ārzemniekiem. Darbā tika analizēta G. Olporta starpgrupu kontakta teorija un starpgrupu konfliktu teorija, kas noderēja aptaujas anketas izstrādē un iegūto rezultātu interpretēšanai. Pētījumā tika pielietota kvantitatīvā …
The influence of solvent on conformational properties of peptides with Aib residue—a DFT study
2017
The conformational propensities of the Aib residue on the example of two model peptides Ac-Aib-NHMe (1) and Ac-Aib-NMe2 (2), were studied by B3LYP and M06-2X functionals, in the gas phase and in the polar solvents. To verify the reliability of selected functionals, we also performed MP2 calculations for the tested molecules in vacuum. Polarizable continuum models (PCM and SMD) were used to estimate the solvent effect. Ramachandran maps were calculated to find all energy minima. Noncovalent intramolecular interactions due to hydrogen-bonds and dipole attractions between carbonyl groups are responsible for the relative stabilities of the conformers. In order to verify the theoretical results,…
Intramolecular proton transfer of serine in aqueous solution. Mechanism and energetics
2000
Serine amino acid in aqueous solution is theoretically studied at the B3PW91/6-31+G** level using a dielectric continuum solvent model. Neutral and zwitterionic structures in the gas phase and in solution are described and the proton-transfer mechanism is discussed. A neutral conformation in which the carboxyl hydrogen atom is already oriented toward the amino group seems to be the absolute energy minimum in the gas phase and the most stable neutral form in solution. The absolute energy minimum in solution is a zwitterionic form. The energy barrier for proton transfer is predicted to be very small, in particular when zero-point-energy contributions are added. Our calculations allow the dyna…
Genetic parameters for somatic cell score according to udder infection status in Valle del Belice dairy sheep and impact of imperfect diagnosis of in…
2010
Abstract Background Somatic cell score (SCS) has been promoted as a selection criterion to improve mastitis resistance. However, SCS from healthy and infected animals may be considered as separate traits. Moreover, imperfect sensitivity and specificity could influence animals' classification and impact on estimated variance components. This study was aimed at: (1) estimating the heritability of bacteria negative SCS, bacteria positive SCS, and infection status, (2) estimating phenotypic and genetic correlations between bacteria negative and bacteria positive SCS, and the genetic correlation between bacteria negative SCS and infection status, and (3) evaluating the impact of imperfect diagno…
Retention of carbaryl by polyether type polyurethane foam: a critical study
2000
This paper reports the retention of carbaryl by polyether type polyurethane foam in a dynamic mode. Several parameters that can influence the extraction of carbaryl from water samples were investigated such as concentration of carbaryl, mass of sorbent in the column, sample pH, saline concentration, solvent washing and sample flow rate. Results show that it is possible to achieve quantitative extractions when the sample flow rate is maintained up to 2.4 mL min−1, a mass of foam of 300 mg and a sample volume of 30 mL in 0.5 NaCl are employed. They also indicate that there is an ether-like solvent extraction mechanism controlling the sorption of the substance by the foam. Some recovery tests …
Identification and quantification of phosphatidylcholines containing very-long-chain polyunsaturated fatty acid in bovine and human retina using liqu…
2010
The retina is one of the vertebrate tissues with the highest content in polyunsaturated fatty acids (PUFA). A large proportion of retinal phospholipids, especially those found in photoreceptor membranes, are dipolyunsaturated molecular species. Among them, dipolyunsaturated phosphatidylcholine (PC) molecular species are known to contain very-long-chain polyunsaturated fatty acids (VLC-PUFA) from the n-3 and n-6 series having 24-36 carbon atoms (C24-C36) and four to six double bonds. Recent interest in the role played by VLC-PUFA arose from the findings that a protein called elongation of very-long-chain fatty acids 4 (ELOVL4) is involved in their biosynthesis and that mutations in the ELOVL…
Near Infrared Spectroscopy Detection and Quantification of Herbal Medicines Adulterated with Sibutramine.
2015
There is an increasing demand for herbal medicines in weight loss treatment. Some synthetic chemicals, such as sibutramine (SB), have been detected as adulterants in herbal formulations. In this study, two strategies using near infrared (NIR) spectroscopy have been developed to evaluate potential adulteration of herbal medicines with SB: a qualitative screening approach and a quantitative methodology based on multivariate calibration. Samples were composed by products commercialized as herbal medicines, as well as by laboratory adulterated samples. Spectra were obtained in the range of 14,000-4000 per cm. Using PLS-DA, a correct classification of 100% was achieved for the external validatio…