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Through a collaborative effort across six Sub-Saharan African countries, using recognized international assessment techniques, 23 stocks of three tick species (Rhipicephalus microplus, Rhipicephalus appendiculatus and Amblyomma variegatum) of economic importance for rural small holder farming communities from East and West Africa were collected from cattle, and evaluated in in vitro larval packet tests (LPT). The results demonstrated medium to high resistance to chlorfenvinphos and amitraz across species. Rhipicephalus microplus demonstrated high level alpha-cypermethrin and cypermethrin resistance. Stocks of A. variegatum (West Africa) and R. appendiculatus (Uganda) demonstrated medium level ivermectin resistance.The four least susceptible stocks (East and West African R. microplus, A. variegatum and R. appendiculatus) were taken into in vivo controlled cattle studies where fipronil was found effective against West and East African R. microplus isolates although persistent efficacy failed to reach 90%. Cymiazole and cypermethrin, and ivermectin based acaricides were partially effective against R. microplus without persistent efficacy. Flumethrin spray-on killed A. variegatum within 72 h for up to 10 days posttreatment, however product application was directly to tick attachment sites, which may be impractical under field conditions. A flumethrin pour-on formulation on goats provided persistent efficacy against A. variegatum for up to one-month. Therapeutic control was achieved against R. appendiculatus through weekly spraying cattle with flumethrin, amitraz or combined cymiazole and cypermethrin. A fipronil pour-on product offered four-week residual control against R. appendiculatus (with slow onset of action).Few studies have assessed and directly compared acaricidal activity in vitro and in vivo. There was some discordance between efficacy indicated by LPT and in vivo results. This observation calls for more research into accurate and affordable assessment methods for acaricide resistance.No single active or product was effective against all three tick species, emphasising the need for the development of alternative integrated tick management solutions.

Software maintenance is a challenging and laborious software management activity, especially for open‐source software. The bugs reports of such software allow tracking maintenance activities and were used in several empirical studies to better predict the bug resolution effort. These reports are known for their large size and contain nonrelevant instances that need to be preprocessed to be suitable for use. To this end, instance selection (IS) has been proposed in the literature as a way to reduce the size of the datasets, while keeping the relevant instances. The objective of this study is to perform an empirical study that investigates the impact of data preprocessing through IS on the performance of bug resolution prediction classifiers. To deal with this, four IS algorithms, namely, edited nearest neighbor (ENN), repeated ENN, all‐k nearest neighbors, and model class selection, are applied on five large datasets, together with five machine learning techniques. Overall, 125 experiments were performed and compared. The findings of this study highlight the positive impact of IS in providing better estimates for bug resolution prediction classifiers, in particular using repeated ENN and ENN algorithms. [ABSTRACT FROM AUTHOR]

In canine leishmaniosis endemic areas, Leishmania infantum may occur in sympatry with the non-pathogenic Leishmania tarentolae, which is associated to reptiles. The potential infectivity of L. tarentolae for mammals raises questions about the interactions between the two Leishmania species, and the potential cross-immune protection in dogs. This study aimed to assess the outcome of experimental L. tarentolae infection in dogs, determining: i) the anti-L. tarentolae antibody production, ii) the duration of the immunity and cytokine expression, and iii) the possible pathogenic effect in the canine host. Twelve purpose-bred beagle dogs were randomly allocated to three groups (intravenous inoculation, G1; intradermal inoculation, G2; negative control, G3). G1 and G2 dogs were inoculated twice (day 0, day 28) with 108 promastigotes of L. tarentolae strain (RTAR/IT/21/RI-325) isolated from a Tarentola mauritanica gecko. The animals were followed until day 206. Blood, serum, conjunctival swabs and lymph node aspirate samples were collected monthly and bone marrow, liver and spleen biopsies on day 91. Hematological and biochemical parameters were assessed monthly, as well as serology (IFAT and ELISA) and molecular identification of L. tarentolae. Mononuclear cells (PBMC) were obtained to assess the cytokine expression through in vitro stimulation or (re-) infection. Data from this study demonstrated that DNA from L. tarentolae is detectable up to 3 months post-infection, with seroconversion after day 28. Moreover, the non-pathogenic nature of L. tarentolae was confirmed, with a neutral Th1/Th2 polarization, and a possible shift to Th1 phenotype after derived macrophages (re-) infection, as demonstrated by the expression of IFN-gamma. Therefore, L. tarentolae demonstrated a great potential as a surrogate pathogen and/or immune-prophylaxis/immune-therapy against Leishmania infections in dogs and humans. Author summary: The reptilian-associated Leishmania tarentolae may be infective for mammals, which raises questions about a potential cross-immune protection towards Leishmania infantum in dogs. This study aimed to assess the outcome of experimental L. tarentolae infection in the canine host. Twelve purpose-bred beagle dogs were allocated into three groups (intravenous inoculation, G1; intradermal inoculation, G2; negative control, G3). The first two groups were inoculated twice (day 0, day 28) with 108 promastigotes of L. tarentolae, and were followed until day 206. Hematological and biochemical parameters were assessed, as well as serology (IFAT and ELISA), molecular identification and cytokine expression. Results demonstrated that DNA from L. tarentolae is detectable up to 3 months post-infection, with seroconversion after day 28. Moreover, the non-pathogenic nature of L. tarentolae was confirmed, with a neutral Th1/Th2 polarization, and a possible shift to Th1 phenotype (i.e., expression of IFN-gamma). These results suggest that L. tarentolae could be a potential candidate for developing immune strategies, opening new avenues for the prevention of the canine leishmaniasis. [ABSTRACT FROM AUTHOR]

For centuries, the Saharan oasis agro-systems of Adrar region have fed many generations, based on an original organization, based on the efficiency of drainage water on the diversification of crop systems in association with small livestock farming. The aim of the work is to describe the systemic typology of oasis livestock farming in the Adrar region (southwest Algeria). In order to assess the livestock typology, a series of surveys were conducted on 164 farms in the oases of the study region. The analysis reveals that the production system, traditionally aimed at subsistence agriculture. The dominant production system is an intensive system, characterized by intensive mixed food crops (Phoenicuculture, arboriculture, herbaceous crops: cereals, fodder, market gardening, industrial and condiment crops), in association with livestock farming mainly of small ruminants (goats and sheep). The livestock system is characterized by a family type, small in size in traditional management. It is generally managed in stalls and its feed comes mainly from fodder crops, domestic waste and by-products of palm groves. Family livestock farming can be an important source to ensure a certain production of animal origin (milk and meat) for family self-consumption. As a result, it can contribute to ensuring food security, family financial security and improving soil fertility in oasis farm plots. [ABSTRACT FROM AUTHOR]

Background: Software product maintainability prediction (SPMP) is an important task to control software maintenance activity, and many SPMP techniques for improving software maintainability have been proposed. In this study, we performed a systematic mapping and review on SPMP studies to analyze and summarize the empirical evidence on the prediction accuracy of SPMP techniques in current research. Objective: The objective of this study is twofold: (1) to classify SPMP studies reported in the literature using the following criteria: publication year, publication source, research type, empirical approach, software application type, datasets, independent variables used as predictors, dependent variables (e.g. how maintainability is expressed in terms of the variable to be predicted), tools used to gather the predictors, the successful predictors and SPMP techniques, (2) to analyze these studies from three perspectives: prediction accuracy, techniques reported to be superior in comparative studies and accuracy comparison of these techniques. Methodology: We performed a systematic mapping and review of the SPMP empirical studies published from 2000 up to 2018 based on an automated search of nine electronic databases. Results: We identified 82 primary studies and classified them according to the above criteria. The mapping study revealed that most studies were solution proposals using a history-based empirical evaluation approach, the datasets most used were historical using object-oriented software applications, maintainability in terms of the independent variable to be predicted was most frequently expressed in terms of the number of changes made to the source code, maintainability predictors most used were those provided by Chidamber and Kemerer (C&K), Li and Henry (L&H) and source code size measures, while the most used techniques were ML techniques, in particular artificial neural networks. Detailed analysis revealed that fuzzy & neuro fuzzy (FNF), artificial neural network (ANN) showed good prediction for the change topic, while multilayer perceptron (MLP), support vector machine (SVM), and group method of data handling (GMDH) techniques presented greater accuracy prediction in comparative studies. Based on our findings SPMP is still limited. Developing more accurate techniques may facilitate their use in industry and well-formed, generalizable results be obtained. We also provide guidelines for improving the maintainability of software.

While young muscle faithfully regenerates damaged myofibers, aged muscle is impaired. Here the authors show the “anti-aging” protein α-Klotho is upregulated in young muscle after damage via promoter demethylation and this regulation is lost in aging, resulting in mitochondrial damage and an impaired healing response.