227 research outputs found

    Parasitism capacity of Trichogramma pretiosum on eggs of Trichoplusia ni at different temperatures.

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    ABSTRACT: Trichogramma spp. are egg parasitoids of various pest species of Lepidoptera including Trichoplusia ni, an important pest of plants in the genus Brassica. Of the climatic conditions that can impair Trichogramma spp. parasitism capacity, the temperature is critical. Thus, the objective of this research was to evaluate the parasitism capacity of Trichogramma pretiosum on eggs of T. ni at 18, 21, 24, 27, 30, and 33ÂșC; 70±10% RH; and 12/12 hours photophase (L/D). Fresh eggs of the host moth were offered to T. pretiosum daily. The parasitism rate varied between 8 and 11.4 eggs/female at the temperatures evaluated for the first 24 hours. The highest number of parasitized eggs per female occurred at 24ÂșC (53.0 parasitized eggs/female). The period of parasitism and the mean longevity of females were inversely related to the temperature. Temperature heavily influences the parasitism rate of T. pretiosum on eggs of T. ni, and the best overall performance of the parasitoid occurs from 24 to 27ÂșC. RESUMO. Trichogramma spp. sĂŁo parasitoide de ovos de vĂĄrias espĂ©cies pragas de Lepidoptera incluindo Trichoplusia ni, uma importante praga de plantas do gĂȘnero Brassica. Das condiçÔes climĂĄticas que podem influenciar a capacidade de parasitismo de Trichogramma spp., a temperatura Ă© uma das principais. Portanto, o objetivo deste trabalho foi avaliar a capacidade de parasitismo de Trichogramma pretiosum em ovos de T. ni nas temperaturas de 18, 21, 24, 27, 30 e 33ÂșC; 70±10% UR; e 14/12h fotofase. Ovos frescos de T. ni foram oferecidos diariamente para T. pretiosum. A taxa de parasitismo nas primeiras 24h variou de 8 a 11,4 ovos/fĂȘmea do parasitoide entre as temperaturas avaliadas. O maior nĂșmero de ovos parasitados por fĂȘmea ocorreu a 24ÂșC (53,0 ovos parasitados/fĂȘmea). O tempo de parasitismo e a longevidade mĂ©dia dos parasitoides adultos foram inversamente relacionados Ă  temperatura. Temperatura influĂȘncia enormemente no parasitismo de T. pretiosum em ovos de T. ni, e os melhores resultados do parasitoide foram obtidos de 24 a 27ÂșC

    Snakebite: Admissions at a tertiary health care centre in Maharashtra, India

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    Objectives. To determine the outcome, seasonal variation, and death pattern of snakebite cases admitted at the tertiary health care centre in the last 10 years. Methods. This was a record-based retrospective descriptive study at the Dr Shankarrao Chavan Government Medical College and Hospital in Vazirabad, a tertiary health care centre in Maharashtra, India. Results. Out of 5 639 admitted snakebite cases, 65.24% were male. The 16 - 45-year age group accounted for 84.7% of cases; 46% were referred from other health centres, mostly from rural areas; 55.2% occurred during July to September, which coincided with the rainy season in this region; 94.6% of the snakebite patients survived; and 5.4% died. Case fatality rates were higher for females (8.78%) and for bites by neurotoxic snakes (8.91%). Conclusions. Snakebite is a common life-threatening emergency in the study area. Ready availability and appropriate use of antivenom, early referral when required and close monitoring of patients in the hospital will help to reduce mortality from snakebites

    Randomisation and Derandomisation in Descriptive Complexity Theory

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    We study probabilistic complexity classes and questions of derandomisation from a logical point of view. For each logic L we introduce a new logic BPL, bounded error probabilistic L, which is defined from L in a similar way as the complexity class BPP, bounded error probabilistic polynomial time, is defined from PTIME. Our main focus lies on questions of derandomisation, and we prove that there is a query which is definable in BPFO, the probabilistic version of first-order logic, but not in Cinf, finite variable infinitary logic with counting. This implies that many of the standard logics of finite model theory, like transitive closure logic and fixed-point logic, both with and without counting, cannot be derandomised. Similarly, we present a query on ordered structures which is definable in BPFO but not in monadic second-order logic, and a query on additive structures which is definable in BPFO but not in FO. The latter of these queries shows that certain uniform variants of AC0 (bounded-depth polynomial sized circuits) cannot be derandomised. These results are in contrast to the general belief that most standard complexity classes can be derandomised. Finally, we note that BPIFP+C, the probabilistic version of fixed-point logic with counting, captures the complexity class BPP, even on unordered structures

    Supporting User-Defined Functions on Uncertain Data

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    Uncertain data management has become crucial in many sensing and scientific applications. As user-defined functions (UDFs) become widely used in these applications, an important task is to capture result uncertainty for queries that evaluate UDFs on uncertain data. In this work, we provide a general framework for supporting UDFs on uncertain data. Specifically, we propose a learning approach based on Gaussian processes (GPs) to compute approximate output distributions of a UDF when evaluated on uncertain input, with guaranteed error bounds. We also devise an online algorithm to compute such output distributions, which employs a suite of optimizations to improve accuracy and performance. Our evaluation using both real-world and synthetic functions shows that our proposed GP approach can outperform the state-of-the-art sampling approach with up to two orders of magnitude improvement for a variety of UDFs. 1

    European position paper on the management of patients with patent foramen ovale. General approach and left circulation thromboembolism

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    The presence of a patent foramen ovale (PFO) is implicated in the pathogenesis of a number of medical conditions; however, the subject remains controversial and no official statements have been published. This interdisciplinary paper, prepared with involvement of eight European scientific societies, aims to review the available trial evidence and to define the principles needed to guide decision making in patients with PFO. In order to guarantee a strict process, position statements were developed with the use of a modified grading of recommendations assessment, development, and evaluation (GRADE) methodology. A critical qualitative and quantitative evaluation of diagnostic and therapeutic procedures was performed, including assessment of the risk/benefit ratio. The level of evidence and the strength of the position statements of particular management options were weighed and graded according to predefined scales. Despite being based often on limited and non-randomised data, while waiting for more conclusive evidence, it was possible to conclude on a number of position statements regarding a rational general approach to PFO management and to specific considerations regarding left circulation thromboembolism. For some therapeutic aspects, it was possible to express stricter position statements based on randomised trials. This position paper provides the first largely shared, interdisciplinary approach for a rational PFO management based on the best available evidence

    Epistemological framing and novice elementary teachers’ approaches to learning and teaching engineering design

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    As engineering learning experiences increasingly begin in elementary school, elementary teacher preparation programs are an important site for the study of teacher development in engineering education. In this article, we argue that the stances that novice teachers adopt toward engineering learning and knowledge are consequential for the opportunities they create for students. We present a comparative case study examining the epistemological framing dynamics of two novice urban teachers, Ana and Ben, as they learned and taught engineering design during a four‐week institute for new elementary teachers. Although the two teachers had very similar teacher preparation backgrounds, they interpreted the purposes of engineering design learning and teaching in meaningfully different ways. During her own engineering sessions, Ana took up the goal not only of meeting the needs of the client but also of making scientific sense of artifacts that might meet those needs. When facilitating students’ engineering, she prioritized their building knowledge collaboratively about how things work. By contrast, when Ben worked on his own engineering, he took up the goal of delivering a product. When teaching engineering to students, he offered them constrained prototyping tasks to serve as hands‐on contexts for reviewing scientific explanations. These findings call for teacher educators to support teachers’ framing of engineering design as a knowledge building enterprise through explicit conversations about epistemology, apprenticeship in sense‐making strategies, and tasks intentionally designed to encourage reasoning about design artifacts.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151339/1/tea21541_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151339/2/tea21541.pd
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