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Application Techniques (application + techniques)
Selected AbstractsModelling the efficacy of entomopathogenic nematodes in the regulation of invertebrate pests in glasshouse cropsJOURNAL OF APPLIED ECOLOGY, Issue 2 2000A. Fenton Summary 1. ,Entomopathogenic nematodes belonging to the families Heterorhabditidae and Steinernematidae are lethal obligate parasites of a wide range of invertebrate species. These nematodes exhibit many characteristics that make them ideal candidates as biological control agents of insect pests (rapid host death, high reproductive rates, easily mass-reared in vitro, easy application techniques). 2. ,However, at present, the number of pest species to which these nematodes are applied successfully is small. Clearly, there is a need to develop existing knowledge of the nematode into a more complete understanding of the nematode,pest system as a whole. 3. ,To consider the potential of entomopathogenic nematodes as biological control agents, we adopted a generalized analytical modelling approach and, using realistic parameter estimates, determined the conditions under which these nematodes can regulate a pest population. 4. ,Stability analyses suggested that entomopathogenic nematodes may not be capable of regulating a host population to a stable equilibrium. Long-term persistence of the host and nematode population is unlikely, due to the highly destabilizing effects of the parasite,host relationship. As such, these nematodes may be better suited to short-term control through inundative application techniques rather than long-term regulation. 5. ,This preliminary generalized model highlights areas where further work is needed. This includes estimation of the probability of nematode infection in the field, the effect of host size on the transmission cycle and the influence of spatial heterogeneity on stability. [source] Pests, pesticide use and alternative options in European maize production: current status and future prospectsJOURNAL OF APPLIED ENTOMOLOGY, Issue 5 2010M. Meissle Abstract Political efforts are made in the European Union (EU) to reduce pesticide use and to increase the implementation of integrated pest management (IPM). Within the EU project ENDURE, research priorities on pesticide reduction are defined. Using maize, one of the most important crops in Europe, as a case study, we identified the most serious weeds, arthropod pests, and fungal diseases as well as classes and amounts of pesticides applied. Data for 11 European maize growing regions were collected from databases, publications and expert estimates. Silage maize dominates in northern Europe and grain production in central and southern Europe. Crop rotations range from continuous growing of maize over several years to well-planned rotation systems. Weeds, arthropod pests and fungal diseases cause economic losses in most regions, even though differences exist between northern countries and central and southern Europe. Several weed and arthropod species cause increasing problems, illustrating that the goal of reducing chemical pesticide applications is challenging. Pesticides could potentially be reduced by the choice of varieties including genetically modified hybrids, cultural control including crop rotation, biological control, optimized application techniques for chemicals, and the development of more specific treatments. However, restrictions in the availability of alternative pest control measures, farm organization, and the training and knowledge of farmers need to be overcome before the adoption of environmentally friendly pest control strategies can reduce chemical pesticides in an economically competitive way. The complex of several problems that need to be tackled simultaneously and the link between different control measures demonstrates the need for IPM approaches, where pest control is seen in the context of the cropping system and on a regional scale. Multicriteria assessments and decision support systems combined with pest monitoring programs may help to develop region-specific and sustainable strategies that are harmonized within a EU framework. [source] Controlling western corn rootworm larvae with entomopathogenic nematodes: effect of application techniques on plant-scale efficacyJOURNAL OF APPLIED ENTOMOLOGY, Issue 5 2010S. Toepfer Abstract The three larval instars of western corn rootworm (Diabrotica virgifera virgifera LeConte, Coleoptera: Chrysomelidae) feed on the roots of maize, Zea mays (L.). The effects of six application techniques on the plant-scale efficacy of the entomopathogenic nematode species, Heterorhabditis bacteriophora Poinar (Rhabditida: Heterorhabditidae), in controlling D. v. virgifera populations were assessed in seven field plot experiments in southern Hungary between 2004 and 2007. Approximately 230 000 nematodes were applied per row metre using four different stream spray techniques; or, alternatively 400 000 nematodes per square metre using two different flat spray techniques. Nematode efficacy was assessed by comparing the number of emerging adult D. v. virgifera, and root damage between treatments and untreated controls. All tested nematode application techniques reduced D. v. virgifera density by at least 50% (on average across fields and years). The highest reduction in D. v. virgifera density was 68% and occurred when nematodes were applied into the soil together with maize sowing using a fluid solid stream. Rainfall, the day before application likely increased the control efficacy of H. bacteriophora. Using the 0.00,3.00 node injury damage rating scale, we estimated that potential root damage was prevented by 25,79% when H. bacteriophora was applied. Although, H. bacteriophora can effectively be applied with all of the techniques tested, for optimum performance and minimum costs, it is suggested that the nematodes be applied as follows: (i) as a stream requiring 8,10 times less volume of water than flat sprays, or as a granule requiring no water, and (ii) into the soil when sowing maize, requiring less water than soil surface sprays and avoiding the destruction of nematodes by UV radiation and additional machinery use. [source] Recent advances in external skeletal fixationJOURNAL OF SMALL ANIMAL PRACTICE, Issue 3 2001D. D. Lewis While the use of external skeletal fixation was once associated with substantial postoperative morbidity, clinical and experimental studies have led to technological advances and modifications in application techniques that have greatly improved the results obtained with this treatment modality. The past decade saw numerous advances in external skeletal fixator implants, components and instrumentation, including improvements in fixation pin design, and the development of new linear external skeletal fixation systems and economical circular external skeletal fixation systems specifically engineered for use in dogs and cats. In addition, a greater understanding of fixator biomechanics and the pathobiology of the bone-fixation pin interface have improved fixator application practices. This article reviews many of the more significant recent advances in external skeletal fixation. [source] Different application techniques of pathergy testing among dermatologistsJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 10 2010MG Ozden No abstract is available for this article. [source] New ways to enhance the functionality of paperboard by surface treatment,,,a reviewPACKAGING TECHNOLOGY AND SCIENCE, Issue 6 2008Caisa Andersson Abstract This review summarizes recent development of functional materials to improve the barrier properties of paperboard with emphasis on bio-based polymers. Focus is directed to novel application techniques and water-borne, renewable coating materials. Some aspects on substrate properties and the requirements on food packaging are discussed as are the processability, convertability, recyclability and biodegradability of packaging materials. The functionality, advantages and disadvantages of several bio-based polymers are presented in detail. Among these are starch and cellulose derivatives, chitosan, alginate, wheat gluten, whey proteins, polycaprolactone, poly(lactic acid) and polyhydroxyalkanoates. Also discussed is the enhancement of barrier properties by incorporation of nanosized materials, by application of thin protective top coatings and local reinforcement by self-healing agents. Copyright © 2008 John Wiley & Sons, Ltd. [source] CHEMICAL AND PHYSICAL CHARACTERIZATION OF STUCCOS FROM A MEXICAN COLONIAL BUILDING: EL MUSEO DEL CALENDARIO OF QUERETARO*ARCHAEOMETRY, Issue 5 2009MIGUEL GALVÁN-RUIZ Restoration requires the use of appropriate characterization methods and suitable new material preparation processes permit the reproduction of the original material to be as similar as possible in order to be an appropriate application method. The combination of these factors will facilitate a good restoration process. Different stuccos were taken from El Museo del Calendario, a building located in Querétaro, Mexico which was built in the 16th century. All the stucco samples were studied using the characterization process which is proposed in this article. The characterization method consisted of the use of analytical techniques, such as X-ray diffraction, Fourier transform infrared and scanning electron microscopy. This characterization method made reproduction of the original material possible. The new material combined with new application techniques developed in situ will result in a high-quality restoration process. [source] An evaluation of dermoscopy fluids and application techniquesBRITISH JOURNAL OF DERMATOLOGY, Issue 1 2003A.J. Gewirtzman SummaryBackground Dermoscopy, a noninvasive technique used to help physicians better visualize pigmented skin lesions, is becoming widely used by dermatologists. Yet despite its popularity, to our knowledge basic aspects such as the best immersion fluid (IF) to use and proper procedures for applying the IF and dermatoscope have never been the subject of a systematic investigation. Objectives To determine the best techniques for application of IF and the dermatoscope; to discover which IF results in the least amount of air inclusions; to determine which IF provides the best image quality. Methods and materials This study was divided into three phases. Phase I examined several techniques of taking digital dermoscopic photographs in an attempt to eliminate air bubbles. Phase II tested seven IFs to analyse quantitatively the number of air inclusions for each IF. Phase III investigated these same IFs to judge the image quality for each. Results Phase I: in our hands, the best technique to apply an IF is to use an eyedropper and place the IF directly onto the skin in combination with a ,roll-on technique': the dermatoscope's edge is placed on the skin first and is then rotated until the glass plate lies flat against the skin. Phase II: the alcoholic IF resulted in the least amount of air bubble inclusions (70% ethanol, 90% isopropanol and alcoholic disinfectant), while liquid paraffin (a mineral oil) resulted in the most air bubbles. Phase III: dermoscopic structures were equally clear with alcohols and liquid paraffin, but slightly blurry with ultrasound gel and water. Conclusions Although 90% isopropanol performed slightly better in terms of air inclusions, we prefer to use 70% ethanol in most circumstances because it has the advantage of being odourless, unlike its counterpart. Additionally, ethanol will not stain clothing, does not crystallize on the dermatoscope, disinfects and evaporates immediately (does not need to be wiped off). For certain local considerations, such as dermoscopy on mucosa or the nail, we prefer to use ultrasound gel because it will not flow. [source] 4363: Cytostatic and cytotoxic effects of 5-fluorouracil on human corneal epithelial cells and keratocytesACTA OPHTHALMOLOGICA, Issue 2010E MIDENA Purpose To investigate the effects of different 5-Fluorouracil (5-FU) concentrations, exposure times and application techniques on in vitro cultured human corneal cells. Methods Human corneal epithelial cells (HCEC) and human corneal keratocytes (HCK) cultures were exposed to different 5-FU concentration (0.025% to 1%) and incubation times (single 5' to 2 hrs). The cytostatic effect was evaluated as ratio of inhibition of migration towards controls. The cytotoxic effect evaluation included both contrast phase microscopic observations, and viability measures performed using a MTT[3-(4,5-dimethylthiazo-2-yl)-2,5-diphenyltetrazolium bromide; thiazolyl blue] colorimetric assay. The results were expressed as ratio of optical density (OD) reduction 24 hrs after exposures. Results Cytostatic effect is time and dose dependent. Minimal inhibiting dose (ID50) was 0,55% after 1 hour incubation for HCEC; ID50 was 0,5% after 2 hrs incubation for HCK . A 100% inhibitory effect was never observed at any concentration or incubation interval. No cytotoxic changes were observed at 5-FU < 1%; 5-FU 1% showed time-dependent cytotoxic changes just in HCEC cultures. MTT analysis showed no OD reduction at 5-FU concentration < 1%, whereas 1% 5-FU showed OD reduction < 50% at any tested exposure time. HCEC showed higher reduction in OD than HCK. Conclusion 5-FU shows no definite signs of irreversible toxicity to normal cultured corneal epithelial and keratocyte cells at examined concentrations and exposure time. [source] Retrievability of implant-retained crowns following cementationCLINICAL ORAL IMPLANTS RESEARCH, Issue 12 2008Christian Mehl Abstract Objectives: The purpose of this study was to assess the retrievability of cemented implant crowns using two different removal devices. The influence of five cement types and two cement application techniques was evaluated. Methods: Forty copings were cast from a CoCr alloy for 40 tapered titanium abutments (5° taper, 4.3 mm diameter, 6 mm height, Camlog, Germany). Twenty copings were modeled as single crowns, whereas 20 copings were modeled with an extension to simulate fixed partial dentures (FPDs). Before cementation, the inner surfaces of the copings were air-abraded (50 ,m Al2O3 particles at 2.5 bars), while the abutments were used as delivered with machined surfaces. Copings were cemented with eugenol-free zinc oxide (Freegenol), zinc phosphate (Harvard), glass ionomer (Ketac Cem), polycarboxylate (Durelon) and so-called self-adhesive resin (RelyX Unicem) cement. Cement was applied in a thin film band of 1 or 3 mm to the cervical margin of the inner surface of the copings, respectively. After cementation, specimens were stored in saline solution for 24 h. The Coronaflex and a standardized custom-made removal device were used to remove the copings from the abutments. Results: Using the same cement, no statistically significant influence with regard to the type of restoration (crown/FDP), cement application mode and device was detected (P>0.05). Therefore, data of specimens cemented with the same cement were pooled. Median attempts to remove the copings were: zinc oxide: 3, self-adhesive resin: 3, zinc phosphate: 5, glass ionomer: 16 and polycarboxylate: 58. Four levels of significance (P<0.0001) were found: (1) zinc oxide/self-adhesive resin; (2) zinc phosphate; (3) glass ionomer; and (4) polycarboxylate. Conclusions: Zinc phosphate and glass ionomer cement might be suitable for a so-called ,semipermanent' (=retrievable) cementation, while polycarboxylate seems to provide the most durable cementation. [source] | |||||||||||||