Continuering geïntegreerde bestrijding insectenplagen over teeltwisselingen heen

Het instandhouden en beter benutten van een aanwezige populatie roofmijten van de soort T. limonicus kan goed door het selecteren en overleggen van komkommerbladeren van de ene teelt naar de andere. Deze methode zou nog beter benut kunnen worden door bladeren over te leggen op het moment dat de roofmijtenpopulatie een hoog niveau heeft bereikt. In deze experimenten werden de bladeren altijd pas aan het einde van de teelt overgelegd. In de meeste gevallen was de populatie dan alweer teruggezakt naar een laag niveau, nadat trips of kaswittevlieg onderdrukt waren. Het eerder uitleggen van bladeren kan alleen op bedrijven die meerdere teelten van komkommer hebben staan met verschillende teeltperiodes

Biologische bestrijding van Duponchelia : bestrijding van Duponchelia fovealis met bodempredatoren en biologische middelen, met aandacht voor invloeden van gewas, teeltsubstraat en toedieningstechniek

De vlinder Duponchelia fovealis is een opkomend plaagorganisme dat zich in de jaren negentig heeft gevestigd in de Nederlandse kassen. Schade wordt vooral ondervonden in potplanten door vraat van rupsen aan plantendelen. Deze rupsen leven over het algemeen goed verscholen bij de plantvoet, waardoor een bestrijding met insecticiden in dichte gewassen onvoldoende effectief kan zijn. Een alternatief voor insecticiden kan inzet van bodempredatoren zijn. Rupsen en eieren van Duponchelia worden mogelijk wel bereikt met deze rovers, die actief zoeken naar prooien. Het doel van dit onderzoek was het ontwikkelen van een biologisch bestrijdingssysteem, waarmee populaties van Duponchelia tot een acceptabel niveau kunnen worden onderdrukt. In dit onderzoek is daarom gekeken naar de effecten van nieuwe bodempredatoren en de invloed van gewas en substraat op deze bodempredatoren en op Duponchelia zelf. De effecten van een aantal biologische en chemische middelen op Duponchelia zijn onder kasomstandigheden bepaald, waarbij eveneens is gekeken naar combinaties van behandelingen. Tenslotte werd aandacht gegeven aan het belang van spuitfrequentie en toedieningstechniek op de effectiviteit van een verspuitbaar middel

Determinants of Return to Work in Patients with Hand Disorders and Hand Injuries

Introduction Return to work (RTW) in patients with hand disorders and hand injuries is determined by several determinants not directly related to the physical situation. Besides biomedical determinants, work-related and psychosocial determinants may influence RTW as well. This study is conducted to investigate the influence of these potential determinants on RTW in patients with hand disorders and hand injuries. Methods Included 91 patients who were operatively treated for a hand disorder or a hand injury, and who were employed prior to surgery. Patients answered several questionnaires on the aforementioned categories. Potential determinants significantly related to RTW in a univariate analysis were entered in a logistic regression for the total group and the acutely injured patients separately. Results Pain, accident location, job independence and symptoms of post-traumatic stress disorder (PTSD) were univariately associated with RTW. Pain was a determinant for late RTW in the total group and accident location and symptoms of PTSD in the acutely injured group. Conclusion Pain, accident location and symptoms of PTSD were most important in resuming work in hand injured patients or in patients with a hand disorder. These findings may indicate that attention should be paid to the treatment of pain, and to the development of symptoms of PTSD during rehabilitation. It may be necessary to make extra efforts aimed at RTW in patients who sustained their injury on the job

Biological control of broad mites (Polyphagotarsonemus latus) with the generalist predator Amblyseius swirskii

The broad mite is a serious pest of a variety of crops worldwide. Several phytoseiid mites have been described to control these mites. However, broad mites are still one of the major pest problems on greenhouse pepper in South-eastern Spain. The generalist predatory mite A. swirskii is widely used against other pests of pepper plants such as thrips and whiteflies, the latter being a vector of broad mites. We assessed the potential of A. swirskii to control broad mites. The oviposition rate of A. swirskii on a diet of broad mites was lower than on a diet of pollen, but higher than oviposition in the absence of food. Population-dynamical experiments with A. swirskii on single sweet pepper plants in a greenhouse compartment showed successful control of broad mites

Edge-control and surface-smoothness in sub-aperture polishing of mirror segments

This paper addresses two challenges in establishing a new process chain for polishing hexagonal segments for extremely large telescopes:- i) control of edge and corner profiles in small-tool polishing of hexagons, and ii) achieving the required smoothness of the bulk aspheric form. We briefly describe the performance of a CNC-grinding process used to create the off-axis asphere, which established the input-quality for subsequent processing. We then summarize processes for smoothing ground mid-spatials and pre- and corrective polishing using Zeeko CNC machines. The impact of two cases is considered; i) all processing stages are performed after the segment is cut hexagonal, and ii) final rectification of a hexagon after cutting from an aspherised roundel, as an alternative to ionfiguring. We then report on experimental results on witness samples demonstrating edges and corners close to the EELT segment specification, and results on a full-aperture spherical segment showing excellent surface smoothness. © 2012 SPIE

Fast manufacturing of E-ELT mirror segments using CNC polishing

We report on the first-ever demonstration of grinding and polishing full-size, off-axis aspheric, mirror segments as prototypes for an extremely large telescope, processed entirely in the final hexagonal shape. We first describe the overall strategy for controlling form and mid spatial frequencies, at levels in the vicinity of <10nm RMS surface. This relies first on direct CNC grinding of the base-form of these 1.4m segments, using the Cranfield BoX™ machine. The segments are then mounted on a custom designed (Optic Glyndwr Optoelectronic Engineering Group) three segment hydraulic support, and CNC polished on a Zeeko IRP 1600 machine using a variety of custom tooling. We overview the fullaperture and sub-aperture metrology techniques used to close the process-loop and certify quality, all of which operate with the segment in-situ on the IRP1600. We then focus on the pristine edge-definition achieved by the combination of tool-lift and smoothing operations; results never previously demonstrated on full-size pre-cut hexagonal segments. Finally, the paper discusses the feasibility of scaling the process to deliver 931 segments in seven years, as required for the E-ELT project. © 2013 SPIE

Needs, problems and rehabilitation goals of young children with cerebral palsy as formulated in the rehabilitation activities profile for children

Objective: To describe the content of needs, problems and goals of 41 Dutch children with cerebral palsy using the International Classification of Functioning, Disability and Health for Children and Youth (ICF-CY) as a classification system. To evaluate the adherence of formulations of needs, problems and goals to specifications of the Rehabilitation Activities Profile for Children. Methods: Raw text data were extracted and organized. Two raters independently weighed the entries' quality against the specifications and linked the extracted content to ICF-CY categories. Results: In 12% of the reports no needs, and in 24% no principal goals, were formulated. Needs mostly pertained to the activities-and-participation domain (65%), whereas problems and goals covered all 3 ICF-CY domains. None of the needs were prioritized and 79% met the quality criterion of description of a problem/desire. Twenty-four percent of the problems were described in the activity-and-participation domain and 83% referred to a treatable problem. Fifty-six percent of the goals were formulated in terms of intended result/effect and 63% as child/parent actions. Conclusion: Insight is provided into the content of rehabilitation programmes for children with cerebral palsy. To optimize the quality of the reports, research on reasons for non-adherence to specifications of the Rehabilitation Activities Profile is needed

Vaginal noise: prevalence, bother and risk factors in a general female population aged 45–85 years

Item does not contain fulltextINTRODUCTION AND HYPOTHESIS: Vaginal noise (VN) is a symptom of pelvic floor (PF) dysfunction and has been described in a few studies. No other risk factors have been described besides parity and pelvic organ prolapse (POP). Underlying mechanisms of VN are unclear. Aims of this study were to describe prevalence, bother and relation between VN and PF (muscle)(dys)function. METHODS: A cross-sectional study was performed on a general population of 2,921 women (aged 45-85 years). Questionnaires were filled in by 1,397 women, and 800 were selected at random to undergo vaginal examination for POP Quantification and PF muscle function assessment. Chi-square tests, Student's t test and multivariate logistic regression were performed (P < 0.05). RESULTS: Response rate was 62.7%. Prevalence of VN was 12.8%; 72.1% reported only a little bother. Odds ratios for parity and solid stool were high. CONCLUSIONS: VN was strongly related to many symptoms of pelvic floor dysfunction, but it was only causing a little bother

Pelvic floor muscle function in a general female population in relation with age and parity and the relation between voluntary and involuntary contractions of the pelvic floor musculature

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