428 research outputs found

    Detergents and Soaps as Tools for IPM in Agriculture

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    This chapter presents extensive and updated knowledge from scientific and technical reports on the management of agriculture pests using detergents and soaps (D + S), with emphasis on their utility in integrated pest management (IPM) schemes. It includes a review on their environmental, ecological, and toxicological impacts, and their possibilities to become important tools for pest control, especially for those D + S having minimum risk, considering both current and newer products. The present knowledge of their modes of action on arthropods is addressed, revealing the need to better identify the mechanisms to optimize their use against crop pests. Their disadvantages are also analyzed, mainly the lack of residual effect and the potential toxicity to plants. Some ways these problems have been overcome are presented. A comparison of the direct costs of the use of conventional pesticides versus D + S, achieving statistically similar levels of control, is discussed, and scenarios where detergents are competitive (representing lower costs) are presented. There is also a review of the type of compounds reported in the specific literature, which leads to highlight the opportunities to develop agriculture detergents and soaps suited to local agriculture needs. New findings on D + S as co-adjuvants for conventional and biological pesticides, and their potential utilization as safe postharvest treatments against pest, are also presented. Finally, the authorization for soaps and detergents is also discussed, highlighting the need for a joint effort (state agencies, producers, researchers, etc.), in order to increase the offer and the use of detergents and soaps, partially replacing conventional pesticides, to take advantage of their potential as sustainable pest management tools, particularly for IPM programs, but also for organic and conventional productive schemes

    Using of Structural Equation Modeling Techniques in Cognitive Levels Validation

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    When constructing knowledge tests, cognitive level is usually one of the dimensions comprising the test specifications with each item assigned to measure a particular level. Recently used taxonomies of the cognitive levels most often represent some modification of the original Bloom’s taxonomy. There are many concerns in current literature about existence of predefined cognitive levels. The aim of this article is to investigate can structural equation modeling techniques confirm existence of different cognitive levels. For the purpose of the research, a Croatian final high-school Mathematics exam was used (N = 9626). Confirmatory factor analysis and structural regression modeling were used to test three different models. Structural equation modeling techniques did not support existence of different cognitive levels in this case. There is more than one possible explanation for that finding. Some other techniques that take into account nonlinear behaviour of the items as well as qualitative techniques might be more useful for the purpose of the cognitive levels validation. Furthermore, it seems that cognitive levels were not efficient descriptors of the items and so improvements are needed in describing the cognitive skills measured by items

    Field and Laboratory Responses of Male Leaf Roller Moths, Choristoneura rosaceana and Pandemis pyrusana, to Pheromone Concentrations in an Attracticide Paste Formulation

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    Male leafroller moths, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae) and Pandemis pyrusana (Kearfott), were evaluated for responses to a paste formulation loaded with a range of concentrations of the two species' pheromone blends and evaluated in a laboratory wind tunnel and in the field. Response criteria were flight, flight towards the pheromone source, and contact with the pheromone source for the wind tunnel assays, and capture of moths in traps for the field tests. In the wind tunnel and field, responses of males of both species to the paste generally increased as the pheromone concentration in the paste was increased. There was little response by either species to paste with less than 0.16% pheromone. The relationship between pheromone concentration and response for P. pyrusana was linear and for C. rosaceana was sinusoidal over the range of pheromone concentrations tested. These patterns were seen both in the wind tunnel and in the field. Initial release rates from the paste of (Z)-11-tetradecenyl acetate, the main component of the pheromone blends of both species was 3.6–3.8 ng/h. Inhibitory thresholds for responses were not reached for either species, using pheromone concentrations as high as 16%, in either the wind tunnel or the field. For both species, response of males to rubber septa with one mg pheromone loads was similar to the response to the paste with pheromone at concentrations greater than 3–4%. For C. rosaceana, rates of contact with the paste in the wind tunnel were statistically similar to rates of contact in response to conspecific females, with paste pheromone concentrations above 1.6%. Response rates for males of P. pyrusana were significantly lower to the paste than to conspecific females at all paste pheromone concentrations tested. Overall, the optimum pheromone concentration in the paste for moth attraction to contact was 3.2 % for C. rosaceana and 8% for P. pyrusana

    Efecto de la infestación de Micrapate scabrata (Erichson, 1847) (Coleoptera: Bostrichidae) en la degradación de madera y sus consecuencias en algunas propiedades químicas del suelo

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    Micrapate scabrata (Erichson) (Coleoptera: Bostrichidae) is a xylophagous beetle native to Chile. Adults and larvae feed on several native host plants, but also on pruned wood of exotic plants. In this study we assessed the impact of artifi cial M. scabrata infestation on Vitis vinifera L. wood degradation and the subsequent changes in soil properties. First, we periodically sampled, during a four-month period, pruned wood from an infested table grape vineyard, fi nding in average 1 adult/10 cm linear wood. Adults were then placed in large Petri dishes containing uninfested wood samples, and maintained in a climatic chamber for six months. At the end of this period, an average of 65.6% of infested wood had been turned mainly into sawdust. Additionally, the impact of leaving M. scabrata infested pruned wood on potted soil for six months, under laboratory conditions, was also evaluated. Afterwards, the surface soil content of macro elements (N-P-K) and organic matter signifi cantly increased, whereas the soil pH decreased. These results document the signifi cant impact of M. scabrata infestation on pruning wood degradation and the benefi ts to the soil if left on the ground in the ecosystem.Micrapate scabrata (Erichson) (Coleoptera: Bostrichidae) es una especie xilófaga y nativa de Chile. Las larvas y los adultos se alimentan de madera de varias especies nativas, y también de madera de poda de plantas exóticas. En este estudio evaluamos el impacto de una infestación artifi cial de M. scabrata en la degradación de madera de Vitis vinifera L. y los cambios subsecuentes en las propiedades del suelo. Para ello, primero muestreamos madera de poda, durante cuatro meses, en un parronal de uva de mesa infestado, y encontramos en promedio 1 adulto/10 cm lineales de madera. Luego se infestó madera de poda sana, dispuesta en placas de Petri, con adultos, las que se mantuvieron en una cámara climática por seis meses. En ese plazo, un 65.6% de la madera infestada fue convertida principalmente en aserrín. Adicionalmente, se evaluó el efecto de dejar madera de poda infestada por M. scabrata en macetas con suelo, durante seis meses, en condiciones de laboratorio. Luego de ese período, se encontró que el contenido de macro-elementos (N-P-K) y materia orgánica en el suelo aumentó signifi cativamente, mientras que el pH disminuyó. Estos resultados muestran el impacto signifi cativo de la infestación de madera por M. scabrata en su degradación y los benefi cios para la condición del suelo si es dejado en superfi cie en el ecosistema

    Ripple morphology in a sand/mud environment: Guyana, South America.

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    Ripples formed under oscillatory flows in a field setting are examined to construct a simple and accurate method of predicting ripple wavelength in a sand/mud environment. The variables that determine ripple wavelength are very complex, and at least four nondimensional parameters are important. For practical purposes the ripple wavelength normalized by the water semi-excursion (half the orbital diameter) is well determined by the mobility number and the normalized orbital diameter. Ripples with wavelengths proportional to grain size and independent of orbital diameter (anorbital ripples) were predominant in this investigation (60%). Wavelengths dependent on both orbital diameter and grain size (suborbital ripples) constituted the remaining ripples observed. Relating normalized ripple wavelength to the mobility number shows a strong correlation (r\sp2 = 0.7049). However, the normalized ripple wavelength is best explained by the normalized orbital diameter (r\sp2 = 0.7936). Equations derived by other workers to predict ripple wavelength in quartz sand were only moderately successful with fine grain sediments. Therefore, a set of expressions were developed based on the mobility number and the orbital diameter. The derived semi-empirical formulae provide a more accurate method of predicting ripple wavelength for a large set of data from a sand/mud environment.Dept. of Geography. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1996 .C87. Source: Masters Abstracts International, Volume: 37-01, page: 0217. Adviser: A. S. Trenhaile. Thesis (M.A.)--University of Windsor (Canada), 1996

    Identifying the Factors which Affect the Decision to Attain ISO 14000

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    Formally adopted in 1996 by the International Organization of Standardization, ISO 14000 represents a new voluntary international environmental standard which will likely be adopted by the vast majority of corporations. While the literature is clearly divided in its assessment of ISO 14000, an underlying common theme is that the decision to achieve ISO 14000 certification constitutes a major undertaking for most firms. Such an undertaking, it is argued, does not take place in a vacuum. Rather, it is a response to a number of factors or influences. However, no research to date has empirically identified these factors and explained how they can be leveraged into a competitive advantage. In this article, we use qualitative case studies to identify which factors affect the decision to attain ISO 14000 certification and we also explain how these factors can influence the level of success achieved during the certification process

    Arzneimittelinteraktionen mit antiretroviralen Medikamenten

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    Zusammenfassung: Arzneimittelwechselwirkungen sind bei der Behandlung von HIV-Infizierten häufig, da die hochaktive antiretrovirale Therapie immer mehrere Wirkstoffe beinhaltet. Dazu kommen oft Medikamente gegen opportunistische Infektionen und Begleiterkrankungen. Alle Proteaseinhibitoren führen zu einer Inhibition von CYP3A, das im Metabolismus von rund 50% aller Arzneistoffe wichtig ist, beispielsweise Simvastatin, Atorvastatin, Sildenafil und Clarithromycin. Ritonavir ist von allen Proteaseinhibitoren der stärkste Hemmstoff der CYP3A-Aktivität. Dies wird auch genutzt, um die Bioverfügbarkeit anderer Proteaseinhibitoren zu erhöhen. Durch die nichtnukleosidischen Reverse-Transkriptase-Inhibitoren Efavirenz und Nevirapin wird die CYP3A-Aktivität in der Dauertherapie gesteigert. Um Interaktionen vorzubeugen, müssen zu Beginn und bei Therapieende die Dosierungen von CYP3A-Substraten angepasst werden. Interaktionen können auch durch die Beeinflussung von glukuronidierenden Enzymen oder Transportproteinen entstehen. So wird P-Glykoprotein durch Ritonavir gehemmt, was zu einer Erhöhung der Exposition gegenüber vielen Chemotherapeutika führ

    HALLUCINATORY EXPERIENCES IN VISUALLY IMPAIRED INDIVIDUALS: CHARLES BONNET SYNDROME – IMPLICATIONS FOR RESEARCH AND CLINICAL PRACTICE

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    Background: Charles Bonnet syndrome (CBS) refers to visual hallucinations that occur in individuals with preserved cognitive functions associated with visual impairment. Methods: This article reviews occurence of visual hallucinations in subjects with CBS by journals published in English in the Pubmed database in the period 1992-2018. Criteria for selection of appropriate papers were sufficient information and perspicuous view on pathogenesis, epidemiology, clinical presentation and treatment possibilities of CBS. Results: Most commonly, visual hallucinations in patients with CBS are complex, repetitive and stereotyped. Such individuals have preserved insight that those percepts are not real, and there is an absence of secondary explanatory delusions and hallucinations within other modalities. Seeing as the aforementioned percepts do not share all the characteristics of hallucinations, it remains unresolved how they should be referred to. Terms as release hallucinations, one that is reflecting its underlying pathogenesis, or confabulatory hallucinatory experiences have been proposed. Moreover, CBS has also been referred to as phantom vision syndrome and may occur in any ophthalmological disease. It is not particularly connected with loss of function along any level of the visual pathway. Although this syndrome is mostly associated with age-related macular degeneration, glaucoma and cataract, it could be related to almost any other ophthalmological conditions. The incidence of CBS alongside with mostly other ocular pathology is rising as population is ageing. Conclusions: Nonetheless, CBS remains commonly underreported, under recognized and/or misrecognized. Albeit the treatment recommendations and guidelines are not yet fully established, it is important to raise awareness of this specific and distinct condition, which inevitably implicates many differential diagnostic deliberations

    Control de machos de Choristoneura rosaceana (Harris) y Pandemis pyrusana Kearfott (Lepidoptera: Tortricidae) en huertos de manzanos del Estado de Washington (EE.UU.) tratados con diferentes densidades de varias formulaciones atracticidas

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    This is the first report on attracticides loaded with 1.6 or 16% pheromone, with or without 6% permethrin, tested for Choristoneura rosaceana (Harris) and Pandemis pyrusana Kearfott male control. Different densities of attracticide sources (750-3,600 droplets ha-1) homogeneously applied on the canopy were compared in apple (Malus pumila Mill.) orchards. Before attracticide application, no differences in male captures using pheromone baited trap were observed. Afterwards, a significant reduction of captures occurred along with the increasing pheromone concentration, when larger density sources were used. The addition of permethrin into the attracticide formulation, however, did not significantly improve the reduction of males. Overall, these results suggest that mating disruption or other mechanism, instead of the killing effect attributed to attracticides, controlled males. The attracticide formulations matrix reported is suggested to be tested as an alternative to the current ones used for mating disruption. It is suggested to test the attracticide formulation matrix reported as an alternative to the current ones used for mating distuption.\uc9ste es el primer informe del control de machos de Choristoneura rosaceana (Harris) y Pandemis pyrusana Kearfott con atracticidas que contengan 1,6 \uf3 16% de feromona, con o sin permetrina al 6%. Se compararon diferentes densidades de atracticidas (750-3.600 gotas ha-1), aplicadas homog\ue9neamente en la copa de los manzanos (Malus pumila Mill.). Antes de los tratamientos no se observaron diferencias estad\uedsticas en las capturas en trampas cebadas con feromona. Despu\ue9s de aplicar los tratamientos, se observ\uf3 una reducci\uf3n significativa en las capturas, al usar mayores concentraciones de feromona y mayores densidades de gotas por hect\ue1rea. La incorporaci\uf3n de permetrina en la formulaci\uf3n atracticida no mejor\uf3 su actividad en el control de machos. En general, los resultados sugieren que un efecto similar a la confusi\uf3n de c\uf3pula, en lugar de un efecto letal atribuible al atracticida, o bien otro mecanismo, control\uf3 a los machos de estas especies. La matriz grasosa usada en la formulaci\uf3n atracticida se sugiere como una alternativa para ser probada respecto de las formulaciones actualmente usadas para confusi\uf3n de c\uf3pula
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