Search results for "ample"
showing 10 items of 2398 documents
Urban consumers’ attitudes and willingness to pay for functional foods in Iran: A case of dietary sugar
2017
Growing concerns for the incidence of incurable diseases and high costs of health care have attracted consumers to functional foods in the world. These foods are characterized with health improvement, lower risk of disease incidence and less health hazards. The present work examined consumers’ attitude and willingness to pay for dietary sugar in Rasht city, Iran. The studied sample included 125 citizens of Rasht in spring and summer of 2016 whose size was determined by Mitchell and Carson approach. Results of contingent valuation method on the basis of one-and-one-half-bound choice model revealed that the descriptive variable of bid had negative, statistically significant impact on the acce…
(Table 2) Age determination of sediment core NIOP-C2_929
2007
In this study we present a sea surface temperature (SST) record from the western Arabian Sea for the last 20,000 years. We produced centennial-scale d18O and Mg/Ca SST time series of core NIOP929 with focus on the glacial-interglacial transition. The western Arabian Sea is influenced by the seasonal NE and SW monsoon wind systems. Lowest SSTs occur during the SW monsoon season because of upwelling of cold water, and highest SSTs can be found in the low-productivity intermonsoon season. The Mg/Ca-based temperature record reflects the integrated SST of the SW and NE monsoon seasons. The results show a glacial-interglacial SST difference of ~2°C, which is corroborated by findings from other Ar…
Analysis of primary aliphatic short-chain monoamines by LC in water samples
2003
Abstract Several derivatization procedures with o-phthaldialdehyde-N-acetylcysteine (OPA-NAC) were compared for a rapid analysis of primary aliphatic short-chain monoamines in water samples by HPLC using a LiChorospher analytical separation column (100RP18 125 mm ×4 mm i.d., 5 μm). Both the solution and the solid-support assisted off-line derivatization on C18 SPE cartridges were inadequate options because of beginning degradation processes of the instable isoindol derivatives during their transfer to the analytical column. This problem was precluded with the on-column or solid-support assisted on-line derivatization. In the last mentioned procedure, the derivatization took place in a Hype…
Environment and excavation: Pre-lab impacts on ancient DNA analyses
2008
Ancient DNA (aDNA) analyses enjoy an increasing role in palaeontological, archaeological and archaeozoological research. The limiting factor for aDNA studies is the degree of DNA preservation. Our study on 291 prehistoric cattle remains from Europe, the Near East and North Africa revealed that DNA preservation is mainly influenced by geographic and climatic conditions. Especially in hot climates, the preservation of sample material is generally low. We observed that these specimens are prone to further degradation and contamination during and after excavation. We give a description of the main caveats and a short guideline for adequate sample handling in order to facilitate the cooperation …
Evaluation of mycotoxins and their metabolites in human breast milk using liquid chromatography coupled to high resolution mass spectrometry
2014
Humans can be exposed to mycotoxins through the food chain. Mycotoxins are mainly found as contaminants in food and could be subsequently excreted via biological fluids such as urine or human breast milk in native or metabolised form. Since breast milk is usually supposed as the only food for new-borns, the occurrence of mycotoxins in thirty-five human milk samples was evaluated by a newly developed method based on QuEChERS extraction and UHPLC-HRMS detection. The method described here allows the detection of target mycotoxins in order to determine the quality of this initial feeding. The method has been fully validated, with recoveries ranging from 64% to 93% and relative standard deviatio…
Photochemical sample treatment for extracts clean up in PCB analysis from sediments.
2013
Sample purification can be considered the most polluting step of the whole analytical process for PCBs determination in sediment samples. The use of photochemical sample treatment represents an alternative methodology for extracts clean up allowing for a reduction of the used amount of organic solvents. The first application of a photochemical sample treatment for the selective removal or reduction of organic substances interfering with PCBs analyses in sediments is reported. The method's efficiency and robustness were compared with currently used chromatographic purification. Quality parameters such as recovery, linearity and reproducibility were studied. The entire procedure was validated…
Silica Materials Containing Cyclodextrin for Pollutant Removal
2018
This chapter reviews the use of cyclodextrin-silica hybrid systems and cyclodextrin-functionalized silica used as adsorbents or filters for the removal of inorganic and organic pollutants from aqueous solutions in solid-phase extraction and adsorption-oriented processes. Actually, there is a need to develop efficient processes for the synthesis and application of multifunctional silica-based materials for pollutant removal by adsorption or filtration, and for sample purification and concentration using solid-phase extraction.
Charge transfer in high-Tc(Y/Pr)Ba2Cu3O7superlattices
1996
We comment on the charge-transfer model for the unique softening of the apex [O(4)] oxygen observed in Raman spectra of a- and c-oriented (${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$${)}_{\mathit{m}}$(${\mathrm{PrBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$${)}_{\mathit{n}}$ superlattices presented in a recent paper by Ham et al. [Phys. Rev. B 50, 16 598 (1994)]. We find the size of the charge transfer necessary for the observed shift too large to explain the observations. In addition, a conclusion about the unique behavior of both types of superlattices can only be drawn if the sample quality is properly considered. \textcopyright{} 1996 The American Physical Society.
A Sample Selection Model for Unit and Item Nonresponse in Cross-Sectional Surveys
2007
We consider a general sample selection model where unit and item nonresponse simultaneously affect a regression relationship of interest, and both types of nonresponse are potentially correlated. We estimate both parametric and semiparametric specifications of the model. The parametric specification assumes that the errors in the latent regression equations follow a trivariate Gaussian distribution. The semiparametric specification avoids distributional assumptions about the underlying regression errors. In our empirical application, we estimate Engel curves for consumption expenditure using data from the first wave of SHARE (Survey on Health, Aging and Retirement in Europe).
Long term effect of teenage birth on earnings: Evidence from a British cohort study
2016
We use data from the 1970 British Cohort Study and evaluate the effect of teenage motherhood on hourly earnings at age 30, 34, 38, and 42 using alternative non-experimental estimation methods including linear regression, matching methods, and Heckman sample selection models. We conclude that teenage motherhood has a significant negative long-term effect on hourly wages. At age 42, teenage mothers earn 12% less than other women and 29% less than women who have not had any children. When compared to non-teenage mothers, the pay penalty reduces over time and becomes insignificant on the long term.