Biological control of the cherry fruit fly, Rhagoletis cerasi L. (Diptera, Tephriti-dae) by use of entomopathogenic nematodes: first experiences towards practi-cal implementation.

The use of entomopathogenic nematodes (EPN) is a promising approach to control the cherry fruit fly, Rhagoletis cerasi L.. We already demonstrated the high potential of EPN to infect larvae after leaving the cherry for pupation in the soil in laboratory and field experiments. For practice, an appli-cation technique is needed, that is both, grower- and EPN friendly. We tested a tractor mounted spray boom for treatment under the canopy area. The achieved rate of EPN in the soil met the ex-pectations. The activity of EPN in soil samples was high after application, but dropped to 60% of the initial activity within one week. Exact forecasting of larval drop from cherries is another major chal-lenge. To obtain basic data, we recorded the phenology of infestation and larval emergence on trees which were not harvested. Sequential infestation on the same cherry variety was observed and larvae dropped from individual trees for several weeks

Basic results in biological control of the European Cherry Fruit Fly Rhagoletis cerasi L. (Diptera: Tephritidae) with entomopathogenic nematodes

In 2002 and 2003, within the ‚Bundesprogramm Ökologischer Landbau’, initial experiments to control the European cherry fruit fly Rhagoletis cerasi were carried out under laboratory, semi-field and field conditions with several entomopathogenic nematode species and strains. In the laboratory the efficacy of nematodes against R. cerasi larvae, pupae and adults was examined. To characterize the controlling potential, different nematode dosages, exposure temperatures and substrates were tested in cell wells, petri dishes and plastic boxes. In the semi-field experiments plastic fruit boxes, filled with soil, were used. In the field tests R. cerasi-larvae and nematodes were released in defined areas in a cherry orchard of the institute. For evaluation of the experiments, the infestation rates and efficiencies (ABBOTT) were determined. Steinernema carpocapsae and S. feltiae achieved the highest efficacies. In laboratory, infestation rates in cell wells up to 91 % and efficencies up to 96 %, in petri dishes up to 96 %, respectively 98 %, and in plastic boxes 88 %, respectively 89 %, were attained. The experimental substrates like quartz sand or soil type and the tested temperatures did not result in consistent significant differences in laboratoy tests. A dosage below 25 nematodes per cm2 resulted in insufficient infestation rates. In the semi-field experiments a maximum infestation rate of 86 % (efficiency 78 %) and in a first field test an efficiency of 88 % was obtained. R. cerasipupae were not infested. These results indicate a high controlling potential of entomopathogenic nematodes against R cerasi, especially of the steinernematid species S. carpocapsae and S. feltiae. Further experiments under realistic conditions in the field are forcibly necessary before putting this control method into practice

Prüfung von Kartoffelsorten auf deren besondere Eignung für den Ökologischen Landbau

Auf insgesamt sieben langjährig ökologisch bewirtschafteten Flächen wurden in den Jahren 2009 bis 2012 bundesweit Kartoffelsortenversuche in randomisierter Anlage durchgeführt. Insgesamt 18 Sorten der Reifegruppen sehr früh, früh, mittelfrüh und mittelspät/spät wurden als orthogonales Sortiment vorgekeimt ausgepflanzt. Das Vorhaben gliedert sich in zwei Abschnitte. Im ersten wurde das bestehende Datenbanksystem PIAF um wichtige Parameter für zusätzliche Bonituren und vorgezogene Erntetermine ergänzt. Mit Hilfe dreier vorgezogener Zeiternten wurde der Ertragsaufbau der einzelnen Sorten differenziert erfasst. Ergänzende Bonituren am Pflanzgut, im wachsenden Bestand und am Erntegut lieferten zusätzliche Hinweise zu Schädigungen und daraus resultierenden Beeinträchtigungen bei der Vermarktung. Die Zeiternten wurden jeweils 70, 80 und 90 Tage nach dem Pflanzen durchgeführt. Bereits zur ersten Zeiternte lag der mittlere Ertrag bei 200 dt/ha und steigerte sich bis zur dritten Zeiternte auf 343 dt/ha. Bei der Endernte, wie auch bei den Zeiternten, wurde neben dem Knollenertrag der Anteil an Über- und Untergrößen sowie der Marktwareanteil erfasst. Hinzu kam die Bestimmung des Nitratgehaltes in den Knollen der Endernte. Die Auswertung der Erträge erfolgte mit Hilfe der Hohenheim-Gülzower Methode, einem Verrechnungsverfahren, bei dem Datenlücken mit Hilfe adjustierter Werte geschlossen werden können. In einem zweiten Teil wurden Endernteproben von 14 Sorten der sieben Standorte zentral in der Versuchsstation Dethlingen zeitnah nach der Ernte eingangsbonitiert und anschließend eingelagert. Die Lagerung erfolgte unter praxisnahen Bedingungen. Ausgelagert wurde Anfang Januar und Anfang April. Neben den Lagerungsverlusten wurde das Auftreten von Helminthosporium solani und Colletotrichum coccodes auf den Knollen bonitiert. Es zeigten sich sowohl Sorten- als auch Standort- und Jahresunterschiede. Das Vorhaben wurde im Verbund mit der Universität Kassel, Fachgebiet Ökologischer Land- und Pflanzenbau, durchgeführt. Die Koordination lag bei der Landwirtschaftskammer Niedersachsen

Nanostructuring polyetheretherketone for medical implants

Surface roughness is a vital factor for medical implants since the cells of the surrounding tissue interact with the underlying substrate on the micro- and nanometer scales. In order to improve the surface morphology of implants, appropriate large-area micro- and nanostructuring techniques have to be identified being applicable to irregularly shaped structures. We demonstrate that plasma treatments of polyetheretherketone (PEEK) thin films produce nanostructured surfaces in a reproducible manner. They are easily tailored by varying plasma intensity using oxygen and ammonia as process gases. It was observed that roughness and nanostructure density linearly depend on plasma intensity. Oxygen plasma turned out to exhibit a stronger effect compared to ammonia plasma at the same processing conditions. For cell interaction studies, the mean size of the nanostructures was intentionally varied between 10 nm and 100 nm. In vitro experiments revealed that human mesenchymal stem cells (hMSC) adhere inhomogenously on untreated PEEK films, but the plasma treatment with oxygen or ammonia allows the hMSC to adhere and proliferate. Fluorescence microscopy of the cells on the PEEK films turned out to be difficult because of the strong auto-fluorescence of the PEEK substrate. Stains including the whole cell vital stain Calcein-AM allowed cell morphology studies on plasma-treated PEEK films. In the case of the analysis of cell compartments such as the actin cytoskeleton, confocal laser scanning microscopy (CLSM) was successfully applie

Ethics and Leadership: Enablers and stumbling blocks

Many of the scandals, indiscretions and collapses, over the last few years, at formerly venerated organizations were the results of toxic relationships, dubious economic models, opaque workplace paradigms, as well as questionable collective and individual actions and behaviours of people who, ordinarily, would not be considered 'typically criminal'. The individuals involved have typically been people with good education, caring parents, were community contributors and, by all accounts, appeared to be upstanding members of society. Their involvement, therefore, in corrupt acts and relationships thus brings a numbers of issues under questionan important one of which is their ethical maturity, and the forming of that ethical development through important societal institutions such as: religion, education and the family. We set out to understand what some of the stumbling blocks were that prevent individuals from courageously acting on their sometimes vast bases of theoretical/common knowledge with respect to ethics and morals, but which has not yet become common practice. Additionally, we also sought to understand what the various enablers were for individuals who were able to live and act ethically, to further enhance such ethical and moral living and working. Our research sample was 646 middle managers who were all enrolled on the MBA programs of the University of Cape Town (South Africa) and Erasmus University (Netherlands). The research respondents self-reported on both the stumbling blocks and enablers, through writing up their personal experiences for our research. They also reported on what some of the practical actions were that they employed to live and work ethically

Higher PLIN5 but not PLIN3 content in isolated skeletal muscle mitochondria following acute in vivo contraction in rat hindlimb

Contraction-mediated lipolysis increases the association of lipid droplets and mitochondria, indicating an important role in the passage of fatty acids from lipid droplets to mitochondria in skeletal muscle. PLIN3 and PLIN5 are of particular interest to the lipid droplet–mitochondria interaction because PLIN3 is able to move about within cells and PLIN5 associates with skeletal muscle mitochondria. This study primarily investigated: 1) if PLIN3 is detected in skeletal muscle mitochondrial fraction; and 2) if mitochondrial protein content of PLIN3 and/or PLIN5 changes following stimulated contraction. A secondary aim was to determine if PLIN3 and PLIN5 associate and whether this changes following contraction. Male Long Evans rats (n = 21;age, 52 days; weight = 317 6 g) underwent 30 min of hindlimb stimulation (10 msec impulses, 100 Hz/3 sec at 10–20 V; train duration 100 msec). Contraction induced a ~50% reduction in intramuscular lipid content measured by oil red-O staining of red gastrocnemius muscle. Mitochondria were isolated from red gastrocnemius muscle by differential centrifugation and proteins were detected by western blotting. Mitochondrial PLIN5 content was ~1.6-fold higher following 30 min of contraction and PLIN3 content was detected in the mitochondrial fraction, and unchanged following contraction. An association between PLIN3 and PLIN5 was observed and remained unaltered following contraction. PLIN5 may play a role in mitochondria during lipolysis, which is consistent with a role in facilitating/regulating mitochondrial fatty acid oxidation. PLIN3 and PLIN5 may be working together on the lipid droplet and mitochondria during contraction-induced lipolysis

Cusp Catastrophe Models for Cognitive Workload and Fatigue in a Verbally Cued Pictorial Memory Task

Objective: The aim of this study was to evaluate two cusp catastrophe models for cognitive workload and fatigue. They share similar cubic polynomial structures but derive from different underlying processes and contain variables that contribute to flexibility with respect to load and the ability to compensate for fatigue. Background: Cognitive workload and fatigue both have a negative impact on performance and have been difficult to separate. Extended time on task can produce fatigue, but it can also produce a positive effect from learning or automaticity. Method: In this two-part experiment, 129 undergraduates performed tasks involving spelling, arithmetic, memory, and visual search. Results: The fatigue cusp for the central memory task was supported with the quantity of work performed and performance on an episodic memory task acting as the control parameters. There was a strong linear effect, however. The load manipulations for the central task were competition with another participant for rewards, incentive conditions, and time pressure. Results supported the workload cusp in which trait anxiety and the incentive manipulation acted as the control parameters. Conclusion: The cusps are generally better than linear models for analyzing workload and fatigue phenomena; practice effects can override fatigue. Future research should investigate multitasking and task sequencing issues, physical-cognitive task combinations, and a broader range of variables that contribute to flexibility with respect to load or compensate for fatigue. Applications: The new experimental medium and analytic strategy can be generalized to virtually any realworld cognitively demanding tasks. The particular results are generalizable to tasks involving visual search

Sensor Selection to Improve Estimates of Particulate Matter Concentration from a Low-Cost Network

Deployment of low-cost sensors in the field is increasingly popular. However, each sensor requires on-site calibration to increase the accuracy of the measurements. We established a laboratory method, the Average Slope Method, to select sensors with similar response so that a single, on-site calibration for one sensor can be used for all other sensors. The laboratory method was performed with aerosolized salt. Based on linear regression, we calculated slopes for 100 particulate matter (PM) sensors, and 50% of the PM sensors fell within ±14% of the average slope. We then compared our Average Slope Method with an Individual Slope Method and concluded that our first method balanced convenience and precision for our application. Laboratory selection was tested in the field, where we deployed 40 PM sensors inside a heavy-manufacturing site at spatially optimal locations and performed a field calibration to calculate a slope for three PM sensors with a reference instrument at one location. The average slope was applied to all PM sensors for mass concentration calculations. The calculated percent differences in the field were similar to the laboratory results. Therefore, we established a method that reduces the time and cost associated with calibration of low-cost sensors in the field