Detection of the tulip breaking virus (TBV) in tulips using optical sensors

The tulip breaking virus (TBV) causes severe economic losses for countries that export tulips such as the Netherlands. Infected plants have to be removed from the field as soon as possible. There is an urgent need for a rapid and objective method of screening. In this study, four proximal optical sensing techniques for the detection of TBV in tulip plants were evaluated and compared with a visual assessment by crop experts as well as with an ELISA (enzyme immunoassay) analysis of the same plants. The optical sensor techniques used were an RGB color camera, a spectrophotometer measuring from 350 to 2500 nm, a spectral imaging camera covering a spectral range from 400 to 900 nm and a chlorophyll fluorescence imaging system that measures the photosynthetic activity. Linear discriminant classification was used to compare the results of these optical techniques and the visual assessment with the ELISA score. The spectral imaging system was the best optical technique and its error was only slightly larger than the visual assessment error. The experimental results appear to be promising, and they have led to further research to develop an autonomous robot for the detection and removal of diseased tulip plants in the open field. The application of this robot system will reduce the amount of insecticides and the considerable pressure on labor for selecting diseased plants by the crop expert. © 2010 The Author(s

Detection of the tulip breaking virus (TBV) in tulips using optical sensors

The tulip breaking virus (TBV) causes severe economic losses for countries that export tulips such as the Netherlands. Infected plants have to be removed from the field as soon as possible. There is an urgent need for a rapid and objective method of screening. In this study, four proximal optical sensing techniques for the detection of TBV in tulip plants were evaluated and compared with a visual assessment by crop experts as well as with an ELISA (enzyme immunoassay) analysis of the same plants. The optical sensor techniques used were an RGB color camera, a spectrophotometer measuring from 350 to 2500 nm, a spectral imaging camera covering a spectral range from 400 to 900 nm and a chlorophyll fluorescence imaging system that measures the photosynthetic activity. Linear discriminant classification was used to compare the results of these optical techniques and the visual assessment with the ELISA score. The spectral imaging system was the best optical technique and its error was only slightly larger than the visual assessment error. The experimental results appear to be promising, and they have led to further research to develop an autonomous robot for the detection and removal of diseased tulip plants in the open field. The application of this robot system will reduce the amount of insecticides and the considerable pressure on labor for selecting diseased plants by the crop expert. © 2010 The Author(s

I'll stand next to them until they don't need me anymore'. :Voluntary work in debt counseling in Rotterdam

De schuldenproblematiek in Nederland neemt toe. Gemeenten en welzijnsorganisaties ontwikkelen daarom verschillende interventies gericht op vroegsignalering en het toeleiden van burgers met schulden naar professionele schuldhulpverlening. Vrijwilligers spelen een belangrijke rol in deze interventies. Dit artikel biedt inzicht in de waarde en worstelingen van vrijwilligerswerk in deschuldhulpverlening, door de bevindingen te presenteren van een casusonderzoek naar de ervaren effectiviteit van vrijwillige inzet bij een lokaal schuldhulpverleningsproject in Rotterdam. Uit het onderzoek blijkt dat de ervaren effectiviteit van vrijwillige inzet in het project bepaald wordt door zeven factoren: (1) tijd, (2) taal en cultuur, (3) positie als vrijwilliger, (4) warme overdracht, (5) sociale steun, (6) praktische hulp, (7) belangenbehartiging en bemiddeling. De aandachtspunten in het project zijn: (1) onduidelijke taak- en rolverdeling tussen vrijwilligers en beroepskrachten, (2) grensbewaking, (3) begeleidingsduur, (4) verantwoording werkzaamheden en aansturing vrijwilligers, (5) professionele ontwikkeling. De studie laat zien dat vrijwilligers mensen met schuldenproblemen in een vroeger stadium naar professionele schuldhulpverlening kunnen begeleiden en hen sociale en praktische steun bieden. Het begeleiden en ondersteunen van mensen met (ernstige) schuldenproblemen vraagt echter veel van de kennis, vaardigheden en houding van vrijwilligers. Vrijwillige inzet bij schuldhulpverlening is belangrijk, maar kan professionele schuldhulpverlening niet vervangen. TREFWOORDENSchuldhulpverlening, schulden, sociaal werk, vrijwilligers, vrijwilligerswerk, samenwerking beroepskrachten en vrijwilligersABSTRACTHousehold debt problems in the Netherlands are rising. Municipalities and social welfare organisations are developing interventions aimed at guiding people with debt problems to professional debt counselling at an early stage. Volunteers play an important role in these interventions. This article provides insight into the value and struggles of voluntary work in debt counselling, through presenting the findings of a case study into the perceived effectiveness of voluntary work in a debt counselling programme in Rotterdam. The findings show that the perceived effectiveness of voluntary work in the programme depends on seven factors: (1) time, (2) language and culture, (3) position as volunteer, (4) ‘warm transfer’, (5) social support, (6) practical help, (7) advocating and mediating. Bottlenecks in the programme are: (1) unclear task- and role divisions, (2) guarding boundaries, (3) duration of support, (4) accountability and managing volunteers, (5) professional development. The article shows that volunteers can guide people with debt problems to professional debt counselling at an earlier stage and can offer them much needed social and practical support. However, guiding and supporting people with (severe) debt problems requires a specific set of knowledge, skills and attitudes. Voluntary work is important, but should not replace professional debt counselling

Threonine utilization is high in the intestine of piglets

The whole-body threonine requirement in parenterally fed piglets is substantially lower than that in enterally fed piglets, indicating that enteral nutrition induces intestinal processes in demand of threonine. We hypothesized that the percentage of threonine utilization for oxidation and intestinal protein synthesis by the portal-drained viscera (PDV) increases when dietary protein intake is reduced. Piglets (n = 18) received isocaloric normal or protein-restricted diets. After 7 h of enteral feeding, total threonine utilization, incorporation into intestinal tissue, and oxidation by the PDV, were determined with stable isotope methodology [U-(13)C threonine infusion]. Although the absolute amount of systemic and dietary threonine utilized by the PDV was reduced in protein-restricted piglets, the percentage of dietary threonine intake utilized by the PDV did not differ between groups (normal protein 91% vs. low protein 85%). The incorporation of dietary threonine into the proximal jejunum was significantly different compared with the other intestinal segments. Dietary, rather than systemic threonine was preferentially utilized for protein synthesis in the small intestinal mucosa in piglets that consumed the normal protein diet (P < 0.05). Threonine oxidation by the PDV was limited during normal protein feeding. In protein-restricted pigs, half of the total whole-body oxidation occurred in the PDV. We conclude that, in vivo, the PDV have a high obligatory visceral requirement for threonine. The high rate of intestinal threonine utilization is due mainly to incorporation into mucosal protein

Residual confounding after adjustment for age: a minor issue in breast cancer screening effectiveness

Residual confounding, after adjustment for age, is the major criticism of observational studies on breast cancer screening effectiveness. We developed realistic scenarios for the prevalence and strength of risk factors on screened and not screened groups, and explored the impact of residual confounding bias. Our results demonstrate that residual confounding bias is a minor issue in screening programme evaluations

The role of plasma concentrations and drug characteristics of beta-blockers in fall risk of older persons

Beta-blocker usage is inconsistently associated with increased fall risk in the literature. However, due to age-related changes and interindividual heterogeneity in pharmacokinetics and dynamics, it is difficult to predict which older adults are more at risk for falls. Therefore, we wanted to explore whether elevated plasma concentrations of selective and nonselective beta-blockers are associated with an increased risk of falls in older beta-blocker users. To answer our research question, we analyzed samples of selective (metoprolol, n = 316) and nonselective beta-blockers (sotalol, timolol, propranolol, and carvedilol, n = 179) users from the B-PROOF cohort. The associations between the beta-blocker concentration and time to first fall were assessed using Cox proportional hazard models. Change of concentration over time in relation to fall risk was assessed with logistic regression models. Models were adjusted for potential confounders. Our results showed that above the median concentration of metoprolol was associated with an increased fall risk (HR 1.55 [1.11–2.16], p =.01). No association was found for nonselective beta-blocker concentrations. Also, changes in concentration over time were not associated with increased fall risk. To conclude, metoprolol plasma concentrations were associated with an increased risk of falls in metoprolol users while no associations were found for nonselective beta-blockers users. This might be caused by a decreased β1-selectivity in high plasma concentrations. In the future, beta-blocker concentrations could potentially help clinicians estimate fall risk in older beta-blockers users and personalize treatment.</p