1,967 research outputs found
Preliminary Study on the Feasibility of Performing Quantitative Precipitation Estimation Using X-band Radar
IRCTR has built an experimental X-band Doppler po-larimetric weather radar system aimed at obtaining high temporal and spatial resolution measurements of precipitation, with particular interest in light rain and drizzle. In this paper a first analysis of the feasibility of obtaining accurate quantitative precipitation estimation from the radar data performed using a high density network of rain gauges is presented
Recent developments in the rapid analysis of plants and tracking their bioactive constituents
Natural products chemistry has witnessed many new developments in the last 5 years like extractions with subcritical water and ionic liquids, LC/HRMS and LC/SPE/cryo-NMR, UHPLC, TLC/MS, MS-based preparative HPLC, comprehensive chromatography (GC × GC, LC × LC), high-throughput screening, introduction of monolithic columns, miniaturisation, and automated structure identification. Nevertheless identifying bioactive constituents in complex plant extracts remains a tedious process. The classical approach of bioassay guided fractionation is time-consuming while off-line screening of extracts does not provide information on individual compounds and sometimes suffers from false positives or negatives. One way out of this is by coupling chromatography with chemical or biochemical assays, so called high resolution screening. An example is the development of HPLC on-line assays for antioxidants. By the post-column addition of a relatively stable coloured radical like DPPH¿ or ABTS¿+, radical scavengers are detected as negative peaks because in a reaction coil they reduce the model radical to its reduced, non-coloured form. When combined with LC/DAD/MS and LC/SPE/NMR, reliable identification of active constituents becomes possible without the necessity of ever isolating them in a classical sense. Also for finding leads for new drugs, combining HPLC with biochemical assays is interesting but technically more difficult. Most enzymes do not work at the organic modifier concentrations commonly encountered in RP-HPLC and the reaction time is often longer requiring dilution and lengthy coils respectively. Therefore, new techniques have to be implemented to gain the required sensitivity for on-line enzyme assays. For stable analytes, high temperature LC offers a solution to the organic modifier problem. When enzymes are highly expensive, like those used in the screening for Cytochrome P450 inhibitors, miniaturisation to chip format may offer a way out. Microreactors (chips) are not only useful for miniaturising larger assays but also offer completely new prospects in phytochemical analysis. One such application is in the sample clean-up of acids and bases like alkaloids. In a lay-out of three parallel channels of 100 ¿m width with the middle one containing organic phase and the two outer ones water of high pH (feed phase) and low pH (trapping phase) such a chip replaces two classical LLE steps but is much faster and requires less solvents and less manpower input
Eerste varkens gearriveerd in Lelystad!
Aangezien het proefbedrijf is gebouwd in een varkensarm gebied is gekozen voor varkens afkomstig van een SPF-populatie
Роберт Конквест про голокост та голодомор
Purpose – Previous research has demonstrated strong relations between work characteristics (e.g. job demands and job resources) and work outcomes such as work performance and work engagement. So far, little attention has been given to the role of authenticity (i.e. employees’ ability to experience their true selves) in these relations. The purpose of this paper is to explore the relationship of state authenticity at work with job demands and resources on the one hand and work engagement, job satisfaction, and subjective performance on the other hand. Design/methodology/approach – In total, 680 Dutch bank employees participated to the study. Structural equation modelling was used to test the goodness-of-fit of the hypothesized model. Bootstrapping (Preacher and Hayes, 2008) was used to examine the meditative effect of state authenticity. Findings – Results showed that job resources were positively associated with authenticity and, in turn, that authenticity was positively related to work engagement, job satisfaction, and performance. Moreover, state authenticity partially mediated the relationship between job resources and three occupational outcomes. Research limitations/implications – Main limitations to this study were the application of selfreport questionnaires, utilization of cross-sectional design, and participation of a homogeneous sample. However, significant relationship between workplace characteristics, occupational outcomes, and state authenticity enhances our current understanding of the JD-R Model. Practical implications – Managers might consider enhancing state authenticity of employees by investing in job resources, since high levels of authenticity was found to be strongly linked to positive occupational outcomes. Originality/value – This study is among the first to examine the role of authenticity at workplace and highlights the importance of state authenticity for work-related outcomes
The influence of interview style on SIOs’ responsiveness to the suspect’s alibi
In criminal investigations it may happen that the police will collect and use information that is actually incorrect. Making sure that such error is detected and corrected is part of the legal and operational burden placed on any investigating officer, but especially on the Senior Investigative Officer (SIO). This present study explored to what degree different interview styles will affect SIO decision-making, since interviewing witnesses and suspects is an important source of information for the police. A sample of 115 Dutch and Norwegian SIOs therefore performed an online vignette task. They read about a fictitious, but realistic case and received a report of an interview with the suspect. In this interview the suspect had provided an alibi for one of the pieces of information that were disclosed to her, and that actually was an incorrect piece of information. In the report the SIOs received, the interviewer either picked up the alibi (adaptive condition), reacted indifferently to it (neutral) or discredited it right away (maladaptive).
A significant effect was found for interview style being associated with SIOs’ responsiveness: the SIOs who read the adaptive or neutral interview report were significantly more responsive to the alibi than those who read the maladaptive report. The implications of this finding are discussed
Factors associated with non-participation and drop-out in a lifestyle intervention for workers with an elevated risk of cardiovascular disease
<p>Abstract</p> <p>Background</p> <p>Non-response and drop-out are problems that are commonly encountered in health promotion trials. Understanding the health-related characteristics of non-participants and drop-outs and the reasons for non-participation and drop-out may be beneficial for future intervention trials.</p> <p>Methods</p> <p>Male construction workers with an elevated risk of cardiovascular disease (CVD) were invited to participate in a lifestyle intervention study. In order to investigate the associations between participation and CVD risk factors, and drop-out and CVD risk factors, crude and multiple logistic regression analyses were performed. The reasons for non-participation and drop-out were assessed qualitatively.</p> <p>Results</p> <p>20% of the workers who were invited decided to participate; 8.6% of the participants dropped out before the first follow-up measurement. The main reasons for non-participation were 'no interest', 'current (para-)medical treatment', and 'feeling healthy', and for drop-out they were 'lack of motivation', 'current (para-)medical treatment', and 'disappointment'. Participants were 4.2 years older, had a higher blood pressure, higher total cholesterol, and lower HDL cholesterol than non-participants, and were more likely to report 'tiredness and/or stress' and 'chest pain and/or shortness of breath'. After adjusting for age, most risk factors were not significantly associated with participation. Drop-outs were 4.6 years younger than those who completed the study. The prevalence of smoking was higher among non-participants and drop-outs.</p> <p>Conclusion</p> <p>Participants had a worse CVD risk profile than non-participants, mainly because of the difference in age. Non-participants and drop-outs were younger and more likely to be smokers. The main reasons for non-participation and drop-out were health-related. Investigators in the field of health promotion should be encouraged to share comparable information.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN60545588</p
On Distributive Subalgebras of Qualitative Spatial and Temporal Calculi
Qualitative calculi play a central role in representing and reasoning about
qualitative spatial and temporal knowledge. This paper studies distributive
subalgebras of qualitative calculi, which are subalgebras in which (weak)
composition distributives over nonempty intersections. It has been proven for
RCC5 and RCC8 that path consistent constraint network over a distributive
subalgebra is always minimal and globally consistent (in the sense of strong
-consistency) in a qualitative sense. The well-known subclass of convex
interval relations provides one such an example of distributive subalgebras.
This paper first gives a characterisation of distributive subalgebras, which
states that the intersection of a set of relations in the subalgebra
is nonempty if and only if the intersection of every two of these relations is
nonempty. We further compute and generate all maximal distributive subalgebras
for Point Algebra, Interval Algebra, RCC5 and RCC8, Cardinal Relation Algebra,
and Rectangle Algebra. Lastly, we establish two nice properties which will play
an important role in efficient reasoning with constraint networks involving a
large number of variables.Comment: Adding proof of Theorem 2 to appendi
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