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Mixed Samples (mixed + sample)
Selected AbstractsSimultaneous Determination of Copper and Bismuth by Anodic Stripping Voltammetry Using H-Point Standard Addition Method with Simultaneous Addition of AnalytesELECTROANALYSIS, Issue 17 2005Esmaeil Shams Abstract Simultaneous determination of bismuth and copper by anodic stripping voltammetry using H-point standard addition method (HPSAM) with simultaneous addition of analytes is described. The effect of various parameters including acid concentration, accumulation time, accumulation potential and concentration ratio of analytes in the standard solution on the sensitivity and accuracy of method were investigated. The results of applying the H-point standard addition method showed that Cu2+ and Bi3+ could be determined simultaneously with the concentration ratios of Cu2+ to Bi3+ varying from 1,:,15 to 16,:,1 in the mixed sample. The method was successfully applied to the simultaneous determination of copper and bismuth in some synthetic mixtures. [source] PROD-screen , a screen for prodromal symptoms of psychosisINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 2 2003M. Heinimaa Abstract The aim of this study was to describe the PROD-screen, an instrument for screening prodromal symptoms indicating risk for psychotic conversion in the near future. PROD-screen consists of 29 questions assessing performance and symptoms. Clinical construct validity was tested by comparing scores from the unselected general population (GP, n = 64) with those of general psychiatric patients from a community mental health centre (CMHC, n = 107). The concordant validity of PROD-screen for prodromal symptoms of psychosis was assessed in a large epidemiologically mixed sample of research subjects (n = 132) by comparing PROD-screen scores with the prodromal diagnosis made by Structured Interview for Prodromal Symptoms as a gold standard. Using the cut-off point of 2/12 specific symptoms, PROD-screen gave correct classification of prodromal status in 77% of cases, distinguishing prodromal from non-prodromal subjects with reasonable sensitivity (80%) and specificity (75%) in the epidemiologically mixed sample. According to subsample analysis PROD-screen functions well with first-degree relatives of schizophrenic patients and probably also with general population samples, but not with psychiatric outpatients. In conclusion, PROD-screen is a useful tool for screening prodromal symptoms of psychosis and selecting subjects for more extensive research interviews. Copyright © 2003 Whurr Publishers Ltd. [source] Criminal attitudes to violence: Development and preliminary validation of a scale for male prisonersAGGRESSIVE BEHAVIOR, Issue 6 2004Devon L.L. Polaschek Abstract Two studies report on the development and preliminary psychometric properties of a new scale measuring criminal attitudes to violence. In Study 1, the responses of a mixed sample of male prisoners were used to select 20 scale items from a larger pool. The final scale (the Criminal Attitudes to Violence Scale; CAVS) was designed so that it had a single-factor structure and was uncorrelated with a measure of social desirability bias. It demonstrated high internal reliability, and a strong relationship to a self-report measure of physical aggression. Significant differences were found in CAVS mean scores for various offence history comparisons, such as whether or not the offender was currently on sentence for a violent conviction. In the second study, most results from the first study were replicated with an independent sample of male prisoners. Further, compared to another scale measuring attitudes to aggression [the EXPAGG Instrumental subscale; Archer and Haigh, 1997b], the CAVS was a better predictor of general attitudes to crime. Mean CAVS scores were again significantly higher for current violent offenders than those on sentence for other types of offences. Lastly, the CAVS was moderately predictive of estimated risk of reconviction and re-imprisonment. Overall these results suggest that this scale measures the construct of attitudes to criminal violence, which partially overlaps two other constructs: attitudes to aggression and attitudes to crime. Aggr. Behav. 30:484,503, 2004. © 2004 Wiley-Liss, Inc. [source] Target selection patterns in rapeJOURNAL OF INVESTIGATIVE PSYCHOLOGY AND OFFENDER PROFILING, Issue 2 2010Eric Beauregard Abstract Both theoretical and empirical studies of decision making in target selection have shown that this process is highly dependent on the physical environment. However, research specifically investigating decision making in sex offenders' target selection is scarce. The aims of the current study were to (1) identify target selection patterns in a mixed sample of 78 Canadian and Portuguese adult rapists, (2) investigate how geographical decision making influences target selection patterns, and (3) test the influence of the type of environment on target selection patterns. The results indicate that Canadian and Portuguese rapists exhibit different target selection patterns but that their geographical decision making is congruent and consistent with the environment within which they operate. Copyright © 2010 John Wiley & Sons, Ltd. [source] Blindness to alternative scenarios in evidence evaluationJOURNAL OF INVESTIGATIVE PSYCHOLOGY AND OFFENDER PROFILING, Issue 2 2010Eric Rassin Abstract In order to prevent miscarriages of justice, police, prosecution, and judges must remain open to alternative scenarios in which the suspect is in fact innocent. In recent years, however, several studies have delivered results suggesting that open-mindedness is not always standard in criminal procedures. For example, Ask and Granhag (2005) found that police officers' estimation of the incriminating power of investigation findings was not affected by knowledge of an alternative suspect. The current first study replicated these findings in a mixed sample of police officers, district attorneys, and judges. In Study 2, this blindness to alternative scenarios did not emerge in a sample of university students. However, the estimation of the incriminating power of the evidence and the willingness to convict the primary suspect were predicted with the participants' confirmation proneness. Copyright © 2010 John Wiley & Sons, Ltd. [source] Preparation of Nanometer-Sized ,-Alumina Powders by Calcining an Emulsion of Boehmite and Oleic AcidJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2002Chih-Peng Lin This study proposes a method to form ultrafine ,-Al2O3 powders. Oleic acid is mixed with Al(OH)3 gel. The gel is the precursor of the Al2O3. After it is mixed and aged, the mixture is calcined in a depleted oxygen atmosphere between 25° and 1100°C. Oleic acid evaporates and decomposes into carbon during the thermal process. Residual carbon prevents the growth of agglomerates during the formation of ,-Al2O3. The phase transformation in this process is as follows: emulsion ,,-Al2O3,,-Al2O3,,-Al2O3,,-Al2O3. This process has no clear , phase. Aging the mixed sample lowers the formation temperature of ,-Al2O3 from 1100° to 1000°C. The average crystallite diameter is 60 nm, measured using Scherrer's equation, which is consistent with TEM observations. [source] Mixed-longitudinal growth of Karimojong girls and boys in Moroto District, UgandaAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2009Sandra Gray In this article we examine results of a mixed-longitudinal study of child and adolescent growth among agropastoral Karimojong children in Moroto District, northeast Uganda. During a 5-month period from August to December, 2004, longitudinal data were collected for a mixed sample of 104 Karimojong children, aged from birth to 18 years. During a previous study in 1998,1999,we had measured 26 of these children who then ranged in Age between 3 months and 7 years. Most of the children were small and thin relative to accepted growth standards, and prevalence of stunting and wasting in childhood was high. In the period from the end of childhood through adolescence, however, Karimojong girls showed marked variability in annual growth, with some attaining a large adult size relative to what we predicted based on their poor childhood growth. Developmental, evolutionary, and environmental determinants are considered. We conclude that growth of these children reflects exposure to environmental insults that vary unpredictably within relatively short intervals. Variability in the magnitude and timing of these insults among children from different birth-cohorts is probably sufficient to account for so-called "shifting" of growth percentiles in childhood and adolescence in this mixed sample. Am. J. Hum. Biol., 2009. © 2008 Wiley-Liss, Inc. [source] Cover Picture: Electrophoresis 16'2010ELECTROPHORESIS, Issue 17 2010Article first published online: 7 SEP 2010 Issue no. 17 is a regular issue comprising 18 manuscripts distributed over 5 separate parts. Part I has 7 research articles on some aspects of proteins and cell separations. Part II has 3 research articles on nucleic acid research including cloning/amplification, gene regulation and STR analysis. Part III offers ways of measuring diffusion and binding constants in two separate articles. Concentration and detection approaches are treated in 4 research articles making up Part IV. The last two articles in this issue (Part V) are on CEC and EKC describing a mixed mode monolithic stationary phase and a cyclodextrin-modified MEEKC. Featured articles include: Lamp-based wavelength-resolved fluorescence detection for protein capillary electrophoresis: Set-up and detector performance ((doi: 10.1002/elps.201000246)) Electromigration diffusivity spectrometry: A way for simultaneous determination of diffusion coefficients from mixed samples ((doi: 10.1002/elps.201000252)) Sample stacking capillary electrophoretic microdevice for highly sensitive mini Y short tandem repeat genotyping ((doi: 10.1002/elps.201000270)) [source] Electromigration diffusivity spectrometry: A way for simultaneous determination of diffusion coefficients from mixed samplesELECTROPHORESIS, Issue 17 2010Suhua Yang Abstract A novel method was proposed for simultaneous measurement of diffusion coefficients, (D), from mixed samples by electrophoresis and termed electromigration-based diffusivity spectrometry. After theoretical treatment, D- equation for practical use has been deduced. With a modified CE system built in laboratory, electromigration-based diffusivity spectrometry has been realized and validated to suit for fast and accurate determination of diffusivities of mixed aromatic amino acids, phenols and aromatic organic acid, giving diffusivity spectra by peak area versus D, much similar to mass spectra. The precision of the measurement was found to critically depend on pH value of running buffer, which should be so selected that the analytes and internal standards could be charged at above 0.5e. The standards have to be selected at an electric flux far from each other and from analytes. In these cases, sample and running buffer concentrations, voltage and system temperature were found to have only negligible impact on the determination. In our test, the obtained measuring precision was generally kept within 1% for five runs, and the measured values of D agreed well with those from literature, with a deviation of less than 2.2% after the right use of calibration standards. [source] Detection of drug-resistant HIV minorities in clinical specimens and therapy failureHIV MEDICINE, Issue 3 2008S Louvel Objective Particularly for therapy-experienced patients, resistance assessment by genotypic or phenotypic methods produces discordances. This study seeks proof that differences may arise from the fact that genotyping produces a single summary sequence whereas replicative phenotyping (rPhenotyping) functionally detects and assigns resistances in mixed HIV populations. Methods For validation, defined mixes of wild-type and M184V mutant were analysed by rPhenotyping or standard genotyping. Allele-specific and quantitative polymerase chain reaction (PCR) set detection and quantification limits for minor virus populations in vitro and in authentic clinical samples showing geno-/pheno-discrepant lamivudine resistance. Results Allele-specific and real-time PCR methods detected down to 0.3% of mutant M184V. The functional assessment was sensitive enough to reveal <1% of mutant M184V in mixed samples. Also in discordant samples from the diagnostic routine, in which rPhenotyping had identified drug resistance, real-time PCR confirmed minute amounts of mutant M184V. Conclusion By utilizing the replication dynamics of HIV under drug pressure, a rPhenotyping format potently reveals relevant therapy-resistant minority species, even of HIV known to possess reduced replicative fitness. With its rapid turnaround of 8 days and its high sensitivity, our rPhenotyping system may be a valuable diagnostic tool for detecting the early emergence of therapy-threatening HIV minorities or the persistence of residual resistant virus. [source] Prostaglandin E2 production and viability of cells cultured in contact with freshly mixed endodontic materialsINTERNATIONAL ENDODONTIC JOURNAL, Issue 5 2006K. K. Melegari Abstract Aim, To determine whether commonly used endodontic sealers could either induce or increase the release of prostaglandin E2 (PGE2) when in contact with cell types found in the periapical tissues. Methodology, Freshly mixed samples of Roth 801 sealer, Sealapex® and ProRoot® mineral trioxide aggregate (MTA) were placed in contact with cultured macrophages and fibroblasts for 24 h. The supernatant from the cultures was assayed for PGE2 using enzyme-linked immunosorbent assay. Cell viability counts were made. As a positive control, similar cultures were also exposed to lipopolysaccharide and the supernatant analysed for PGE2. Data were compared by anova. Results, The three materials examined in these experiments did not stimulate increased PGE2 release from either of the cell lines. In control cultures, lipolysaccharide increased PGE2 release from macrophages but not from fibroblasts. Viability counts revealed that, whilst Roth 801 sealer caused some cell death in both fibroblasts and macrophages, Sealapex® led to cell death only in the macrophage cultures. ProRoot® MTA did not lead to statistically significant cell death in either culture. Conclusions, Under 24-h culture conditions, the three freshly mixed test materials did not increase directly either production or release of PGE2 from either macrophages or gingival fibroblasts. Roth 801 decreased cell viability counts for both fibroblasts and macrophages. Sealapex® decreases macrophage viability. ProRoot® MTA did not affect viability in either cell line. [source] Structures and properties of the hydrides of light elementsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 4-5 2002Garry T. Smith Abstract Basic geometric and other properties for a number of neutral holovalent hydrides of light elements (M = Li , F)(MHn) are discussed. Their molecular geometries, energies, and vibrational frequencies have been determined from ab initio calculations of benchmark quality. We calculated harmonic vibrational frequencies, zero point vibrational energies, and atomization energies for the deuterides, tritiides, and combinations of them for these light elements. These isotopomers are of great interest for thermonuclear applications because they are often used as thermonuclear fuels or components of such fuels. In fact, only for these substances thermonuclear energy gain exceeds (at some densities and temperatures) the bremsstrahlung loss and other high-temperature losses, i.e., thermonuclear burn-up is possible. The vibrational frequencies are useful in determining the composition of mixed samples by means of spectroscopy. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002 [source] Nanocomposite Formation Through Thermal Decomposition of Mixed Samarium and Magnesium Citrate-Derived Gels Formed by Spray PyrolysisJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2008Thorsten Enz Metal citrate gels of samarium and magnesium were used as precursors for the generation of hollow sphere particles by spray pyrolysis under mild thermal conditions. Six mixtures with different Sm/Mg ratios as well as pure Sm and Mg samples were prepared. As a result of the low synthesis temperature the particles consist of amorphous metal carboxylate networks. The texture of the shells is governed by microporosity yielding the major part of the total surface area. A detailed investigation of thermal decomposition, crystallization, and grain growth behavior was carried out under constant heating rate conditions. The decomposition products are nanocrystalline Sm2O3 and MgO and corresponding two-phase nanocomposites. The pure samarium carboxylate gel features considerably higher thermal stability compared with the one comprised of only magnesium. Accordingly the decomposition behavior of mixed samples is dependent on the Sm/Mg ratio. Furthermore it is shown that small amounts of MgO are able to slow down the kinetics of grain growth of Sm2O3 whereas high amounts are necessary to significantly reduce the final grain size at 1000°C. [source] Identification of human calculi with time-of-flight secondary ion mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 2 2010C. Amjad A. Ghumman Time-of-flight secondary ion mass spectrometry was used to study four human calculi and to compare the results with those from twelve commercially available urinary calculi minerals including three organic compounds (L-cystine, uric acid and sodium urate). Phase identification of calcium phosphate compounds was carried out by considering the relative ion abundances of [Ca2O]+ and [CaPO2]+. Deprotonated [M,H], and protonated [M+H]+ uric acid were detected and used for component recognition in pure uric acid and in the mixed samples of struvite, calcium oxalate and uric acid. Iodine related to the medical history of a patient was also detected. Copyright © 2009 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||