859 research outputs found
Within- and between-pen transmission of Classical Swine Fever Virus: a new method to estimate the basic reproduction ratio from transmission experiments
We present a method to estimate basic reproduction ratio R0 from transmission experiments. By using previously published data of experiments with Classical Swine Fever Virus more extensively, we obtained smaller confidence intervals than the martingale method used in the original papers. Moreover, our method allows simultaneous estimation of a reproduction ratio within pens R0w and a modified reproduction ratio between pens R'0b. Resulting estimates of R0w and R'0b for weaner pigs were 100 (95% CI 54.4-186) and 7.77 (4.68-12.9), respectively. For slaughter pigs they were 15.5 (6.20-38.7) and 3.39 (1.54-7.45), respectively. We believe, because of the smaller confidence intervals we were able to obtain, that the method presented here is better suited for use in future experiments
Nutzung von Pflanzenextrakten zur Kontrolle der Krautfäule (P. infestans) im ökologischen Kartoffelbau
Der Befall mit dem Erreger der Kraut- und Knollenfäule (P. infestans) hat durch frühzeitigen Verlust der Assimilationsfläche regelmäßig erhebliche Ertragsverluste im Ökologischen Kartoffelbau zur Folge. Neben einer Reihe von vorbeugenden Maßnahmen, inbesondere Wahl toleranter Sorten und Vorkeimen des Pflanzgutes (KARALUS 1995, MEINCK 1999), sind zur direkten effizienten Kontrolle derzeit nur Kupferverbindungen zugelassen. Ein weitgehend unerforschtes Potential zur Kontrolle dieses Oomyceten liegt in der Nutzung von Pflanzenextrakten, diese Wirkung wurde in Feldversuchen untersucht
Malaria and land use: a spatial and temporal risk analysis in Southern Sri Lanka
Malaria / Waterborne diseases / Disease vectors / Land use / Water use / GIS / Statistical analysis / Risks / Mapping / Public health / Sri Lanka / Uda Walawe / Thanamalvila / Embilipitiya
Влияние электромагнитного состояния турбоагрегата на работоспособность его узлов. Диагностика, демагнитезация
Рассмотрены условия возникновения электроэрозионных повреждений узлов турбоагрегатов, а так же их характерные признаки. Даны рекомендации по диагностике и устранению электроэрозии на турбоагрегатах находящихся в эксплуатации.
При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/21587There considered conditions resulting in occurring electroerozion damage sites in turbine unit, as well as their characteristic features. There given recommendations concerning diagnosis and elimination of electroerozion on turbine units being in operation.
При цитировании документа, используйте ссылку http://essuir.sumdu.edu.ua/handle/123456789/2158
Fairness-enhancing interventions in stream classification
The wide spread usage of automated data-driven decision support systems has
raised a lot of concerns regarding accountability and fairness of the employed
models in the absence of human supervision. Existing fairness-aware approaches
tackle fairness as a batch learning problem and aim at learning a fair model
which can then be applied to future instances of the problem. In many
applications, however, the data comes sequentially and its characteristics
might evolve with time. In such a setting, it is counter-intuitive to "fix" a
(fair) model over the data stream as changes in the data might incur changes in
the underlying model therefore, affecting its fairness. In this work, we
propose fairness-enhancing interventions that modify the input data so that the
outcome of any stream classifier applied to that data will be fair. Experiments
on real and synthetic data show that our approach achieves good predictive
performance and low discrimination scores over the course of the stream.Comment: 15 pages, 7 figures. To appear in the proceedings of 30th
International Conference on Database and Expert Systems Applications, Linz,
Austria August 26 - 29, 201
Malaria and Irrigated Crops, Accra, Ghana
We investigated the prevalence of malaria and associated risk factors in children living in urban Ghana. Malaria prevalence was associated with low hemoglobin concentration, low socioeconomic status, and higher age. Our findings indicate that African urban poor are seriously affected by malaria and that irrigated agriculture may increase this risk
Modelization of flow electrification in a polymer melt
Flow electrification of polymer melts is an important side effect of polymer
processing. The studies dealing with this phenomenon are seldom and most of the
scientific work has been focused on flow electrification of aqueous and
insulating Newtonian liquids. From that prior art it is well established that
the flow electrification in Newtonian liquids is a consequence of the formation
of an ionic double layer. Convection of this layer induces the electrification
of the liquid at the outlet of the pipe. In those models, the key parameters
governing the flow electrification are thus the intrinsic electrical properties
of the polymer and the flow characteristics. In this work, we reconsider the
assumptions made previously and we propose a new approach to modelise the flow
electrification in the particular case of non-Newtonian polymer materials in
laminar flow conditions. We establish that, a key parameter for the
electrification quantification in the polymer melt is the shape of the velocity
profile. Additionally, in some cases, we show that a slip velocity at the
polymer/die wall interface must be considered to describe accurately the
electrification. As a consequence, we deduce that the slip velocity at the
interface can be calculated by measuring the electrification: this work gives
an alternative manner to measure the slip velocity during polymer flow
Updated cost-effectiveness and risk-benefit analysis of two infant rotavirus vaccination strategies in a high-income, low-endemic setting.
Since 2013, a biennial rotavirus pattern has emerged in the Netherlands with alternating high and low endemic years and a nearly 50% reduction in rotavirus hospitalization rates overall, while infant rotavirus vaccination has remained below 1% throughout. As the rotavirus vaccination cost-effectiveness and risk-benefit ratio in high-income settings is highly influenced by the total rotavirus disease burden, we re-evaluated two infant vaccination strategies, taking into account this recent change in rotavirus epidemiology
A mathematical model for the intracellular circadian rhythm generator
A mathematical model for the intracellular circadian rhythm generator has been studied, based on a negative feedback of protein products on the transcription rate of their genes. The study is an attempt at examining minimal but biologically realistic requirements for a negative molecular feedback loop involving considerably faster reactions, to produce (slow) circadian oscillations. The model included mRNA and protein production and degradation, along with a negative feedback of the proteins upon mRNA production. The protein production process was described solely by its total duration and a nonlinear term, whereas also the feedback included nonlinear interactions among protein molecules. This system was found to produce robust oscillations in protein and mRNA levels over a wide range of parameter values. Oscillations were slow, with periods much longer than the time constants of any of th
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