Proficiency Testing of Viral Marker Screening in African Blood Centers - Seven African Countries, 2017.

A 2014 report evaluating accuracy of serologic testing for transfusion-transmissible viruses at African blood center laboratories found sensitivities of 92%, 87%, and 90% for detecting infections with human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV), respectively (1). Following substantial investments in national blood transfusion service (NBTS) laboratories, in 2017 investigators tested proficiency at 84 blood center laboratories (29 NBTS and 55 non-NBTS) in seven African countries. A blinded panel of 25 plasma samples was shipped to each participating laboratory for testing with their usual protocols based on rapid diagnostic tests (RDTs) (2) and third and fourth generation enzyme immunoassays (EIA-3 and EIA-4). Sensitivity and specificity were estimated using separate regression models that clustered assays by laboratory and adjusted for assay type and NBTS laboratory status. Mean specificities were ≥95% for all three viruses; however, mean sensitivities were 97% for HIV-positive, 76% for HBV-positive, and 80% for HCV-positive samples. Testing sensitivities for all viruses were high when EIA-3 assays were used (≥97%). Lower sensitivities for HBV-positive samples and HCV-positive samples were associated with assay types other than EIA-3, used primarily by non-NBTS laboratories. Proficiency for HIV testing has improved following international investments, but proficiency remains suboptimal for HBV and HCV testing. In sub-Saharan African blood centers, the quality of rapid tests used for HBV and HCV screening needs to be improved or their use discouraged in favor of EIA-3 tests

Test Generation and Evaluation from High-Level Properties for Common Criteria Evaluations - The TASCCC Testing Tool

International audienceIn this paper, we present a model-based testing tool resulting from a research project, named TASCCC. This tool is a complete tool chain dedicated to property-based testing in UML/OCL, that integrates various technologies inside a dedicated Eclipse plug-in. The test properties are expressed in a dedicated language based on property patterns. These properties are then used for two purposes. First, they can be employed to evaluate the relevance of a test suite according to specific coverage criteria. Second, it is possible to generate test scenarios that will illustrate or exercise the property. These test scenarios are then unfolded and animated on the Smartesting's CertifyIt model animator, that is used to filter out infeasible sequences. This tool has been used in industrial partnership, aiming at providing an assistance for Common Criteria evaluations, especially by providing test generation reports used to show the link between the test cases and the Common Criteria artefacts

Influence de l’Image et de la Valence de l’Experience sur la Fidelite a la Marque

Dans un environnement commercial en perpétuelle mutation, les consommateurs se trouvent confrontés à un large éventail d'options et d'offres. Face à l'augmentation du nombre de marques concurrentes proposant des produits similaires, leur tendance à changer de préférences s'est intensifiée. Dans un tel contexte, établir et préserver des relations durables avec les clients par le biais de la fidélité représente un défi crucial pour les gestionnaires de marques et les professionnels du marketing. L'objectif de cette étude est d'approfondir la compréhension du mécanisme de fidélisation et des éléments qui le stimulent. Pour ce faire, une méthode expérimentale a été appliquée sur un échantillon de 240 étudiants de l'Université Félix Houphouët Boigny, répartis en huit groupes expérimentaux. Ces groupes ont été exposés à des scénarios où deux marques de téléphones, choisies suite à une pré-enquête pour leur image de marque, ont été mises en concurrence. Les principaux résultats obtenus montrent que, quelle que soit l’image de marque, les groupes soumis à la valence positive de l’expérience ont l’intention de réitérer leur achat de la marque, contrairement aux groupes soumis à la valence négative de l’expérience. Par ailleurs, après analyse des niveaux de fidélité, il apparaît que les marques perçues positivement attirent davantage de fidélité que celles perçues négativement, sans égard à la valence de l’expérience mise en jeu. Cette recherche met en évidence l'influence de l'image de marque et de la valence de l'expérience sur la fidélité des consommateurs, tout en soulignant que le lien entre la valence de l'expérience et la fidélité n'est pas systématique. Ces découvertes offrent des perspectives importantes aux professionnels du marketing désireux de comprendre les dynamiques de fidélité selon différents types de marques.   In a constantly evolving commercial environment, consumers find themselves faced with a broad spectrum of options and offers. Given the increase in the number of competing brands offering similar products, their tendency to change preferences has intensified. In such a context, establishing and maintaining long-term relationships with customers through loyalty presents a crucial challenge for brand managers and marketing professionals. The purpose of this study is to deepen the understanding of the loyalty mechanism and the elements that stimulate it. To achieve this, an experimental method was applied to a sample of 240 students from Félix Houphouët Boigny University, divided into eight experimental groups. These groups were exposed to scenarios where two phone brands, selected based on a pre-survey for their brand image, were put in competition. The main findings show that regardless of the brand image, groups subjected to a positive valence of the experience intend to repeat their purchase of the brand, unlike groups subjected to a negative valence of the experience. Furthermore, upon analyzing levels of loyalty, it appears that brands perceived positively attract more loyalty than those perceived negatively, regardless of the valence of the experience involved. This research highlights the influence of brand image and experience valence on consumer loyalty, while emphasizing that the link between experience valence and loyalty is not systematic. These findings offer significant insights for marketing professionals seeking to understand loyalty dynamics across different types of brands

Influence de l’Image de Marque et de la Valence de l“Expérience sur la Fidélité à la Marque

Les études actuelles mettent de plus en plus en avant l’importance de la fidélité des clients dans la réussite d’une entreprise. Afin d’approfondir notre compréhension du processus de fidélisation et des facteurs qui l’alimentent, cette étude, principalement expérimentale, a été menée auprès 240 participants régulièrement inscrits à l’Université Félix Houphouët Boigny. Les données recueillies à l’aide du questionnaire et analysées via le logiciel SPSS révèlent un lien étroit entre la fidélité à la marque et les variables telles que l’image de marque et la valence de l’expérience du consommateur. Cependant, cette relation n’est pas systématique. Plus précisément, malgré une expérience positive, il arrive que certains participants changent de marque au détriment de la marque perçue positivement. La fidélité s’avère plus marquée envers les marques ayant une image favorable. Ces résultats ont des implications directes pour des professionnels du marketing qui cherchent à comprendre les manifestations de la fidélité pour différents types de marques.   Current studies are increasingly highlighting the importance of customer loyalty to a company's success. In order to deepen our understanding of the loyalty process and the factors that drive it, this mainly experimental study was conducted with 240 participants regularly enrolled at the Université Félix Houphouët Boigny. The data collected using the questionnaire and analysed using SPSS software revealed a close link between brand loyalty and variables such as brand image and the valence of the consumer experience. However, this relationship is not systematic. More specifically, despite a positive experience, some participants may switch to a brand that is perceived as positive. Loyalty is more marked towards brands with a favourable image. These results have direct implications for marketing professionals seeking to understand the manifestations of loyalty for different types of brands

Learning bio-inspired head-centric representations of 3D shapes in an active fixation setting

When exploring the surrounding environment with the eyes, humans and primates need to interpret three-dimensional (3D) shapes in a fast and invariant way, exploiting a highly variant and gaze-dependent visual information. Since they have front-facing eyes, binocular disparity is a prominent cue for depth perception. Specifically, it serves as computational substrate for two ground mechanisms of binocular active vision: stereopsis and binocular coordination. To this aim, disparity information, which is expressed in a retinotopic reference frame, is combined along the visual cortical pathways with gaze information and transformed in a head-centric reference frame. Despite the importance of this mechanism, the underlying neural substrates still remain widely unknown. In this work, we investigate the capabilities of the human visual system to interpret the 3D scene exploiting disparity and gaze information. In a psychophysical experiment, human subjects were asked to judge the depth orientation of a planar surface either while fixating a target point or while freely exploring the surface. Moreover, we used the same stimuli to train a recurrent neural network to exploit the responses of a modelled population of cortical (V1) cells to interpret the 3D scene layout. The results for both human performance and from the model network show that integrating disparity information across gaze directions is crucial for a reliable and invariant interpretation of the 3D geometry of the scene

The role of coinfections in HIV epidemic trajectory and positive prevention: a systematic review and meta-analysis.

OBJECTIVES: Recurrent or persistent coinfections may increase HIV viral load and, consequently, risk of HIV transmission, thus increasing HIV incidence. We evaluated the association between malaria, herpes simplex virus type 2 (HSV-2) and tuberculosis (TB) coinfections and their treatment on HIV viral load. DESIGN: Systematic review and meta-analysis of the association of malaria, HSV-2 and TB coinfections and their treatment with HIV viral load. METHODS: PubMed and Embase databases were searched to 10 February 2010 for studies in adults that reported HIV plasma and/or genital viral load by coinfection status or treatment. Meta-analyses were conducted using random-effects models. RESULTS: Forty-five eligible articles were identified (six malaria, 20 HSV-2 and 19 TB). There was strong evidence of increased HIV viral load with acute malaria [0.67 log(10) copies/ml, 95% confidence interval (CI) 0.15-1.19] and decreased viral load following treatment (-0.37 log(10) copies/ml, 95% CI -0.70 to -0.04). Similarly, HSV-2 infection was associated with increased HIV viral load (0.18 log(10) copies/ml, 95% CI 0.01-0.34), which decreased with HSV suppressive therapy (-0.28 log(10) copies/ml, 95% CI -0.36 to -0.19). Active TB was associated with increased HIV viral load (0.40 log(10) copies/ml, 95% CI 0.13-0.67), but there was no association between TB treatment and viral load reduction (log(10) copies/ml -0.02, 95% CI -0.19 to 0.15). CONCLUSION: Coinfections may increase HIV viral load in populations where they are prevalent, thereby facilitating HIV transmission. These effects may be reversed with treatment. However, to limit HIV trajectory and optimize positive prevention for HIV-infected individuals pre-antiretroviral therapy, we must better understand the mechanisms responsible for augmented viral load and the magnitude of viral load reduction required, and retune treatment regimens accordingly

Strengthening the Effectiveness of Aid Delivery in Teacher Education: A Fiji Case Study

As a result of increasing development challenges and higher aid allocations to the Pacific, questions of aid effectiveness have become increasingly important. Efforts to professionalise aid delivery tools have been accompanied by debates over whether delivery tools are effective and compatible with more democratic and empowering relationships with beneficiaries. My research examines the effectiveness of international aid to teacher development, using the AusAID funded projects at Lautoka Teachers' College as a case study and the Fiji College of Advanced Education as background study. The conditions governing aid delivery mechanisms are explored, including logical frameworks, participatory processes, and financial probity. These conditions have been drawn from the 'Paris Declaration of Aid Effectiveness' and each is considered to be critical if aid effectiveness is to be enhanced and the investment sustained. Based on participatory research methodology, carried out through 'talanoa sessions', semià à ¢ structured interviews, and analysis of programme documents, the study explored the extent to which aid programmes and management practices are constrained by donor conditions, succeed in meeting their stated aims, and what sort of unintended consequences are generated. Further, the research identified how aid can best improve future aid to the Fiji education system through its delivery, impact and sustainability for national development, as laid out in the Pacific Principles of Aid Effectiveness The study also highlights the growing convergence between the 'aid donors' interests' and 'aid recipients' needs'. The debate on this relationship is necessary to reinvigorate thinking on the effectiveness of aid delivery for Fiji. The study draws up a practical framework, an aid bure designed as a heuristic device to assess the effectiveness of aid delivery for Fiji. The model may also be relevant to the wider Pacific context, and contribute to the global quest for a concrete guide to best practice which above all will continue to foster more sensitive, effective and enduring links between recipient countries and international aid donors

Learning bio-inspired head-centric representations of 3D shapes in an active fixation setting

When exploring the surrounding environment with the eyes, humans and primates need to interpret three-dimensional (3D) shapes in a fast and invariant way, exploiting a highly variant and gaze-dependent visual information. Since they have front-facing eyes, binocular disparity is a prominent cue for depth perception. Specifically, it serves as computational substrate for two ground mechanisms of binocular active vision: stereopsis and binocular coordination. To this aim, disparity information, which is expressed in a retinotopic reference frame, is combined along the visual cortical pathways with gaze information and transformed in a head-centric reference frame. Despite the importance of this mechanism, the underlying neural substrates still remain widely unknown. In this work, we investigate the capabilities of the human visual system to interpret the 3D scene exploiting disparity and gaze information. In a psychophysical experiment, human subjects were asked to judge the depth orientation of a planar surface either while fixating a target point or while freely exploring the surface. Moreover, we used the same stimuli to train a recurrent neural network to exploit the responses of a modelled population of cortical (V1) cells to interpret the 3D scene layout. The results for both human performance and from the model network show that integrating disparity information across gaze directions is crucial for a reliable and invariant interpretation of the 3D geometry of the scene

Design of a University Course for the Training of Biology Teachers in a Virtual Environment (Analysis of Results Taking into Account Students' Attitudes to the E-learning)

Over the last decade, the concept of "designing e-learning" in the field of higher education has been in the focus of various research communities. Given the increasing number of e-learning publications, the issue of a university course model is becoming a widely discussed topic. The aim of the article is to present a specific solution related to the design of a traditionally organized course in electronic, for the preparation of future teachers of biology. The research process of designing a theoretically based model of pedagogical activity within the framework of a university e-learning course, including stepwise steps in its creation, following the phases of the ADDIE model, is briefly described. Using statistical tests to verify hypotheses (relative percentages), a comparison of the results obtained, taking into account the attitudes of the students before and after the e-learning, was made

The use of artificial intelligence in the prevention and management of bleeding disorders: a systematic review

BackgroundBleeding disorders, including hemophilia, von Willebrand disease (VWD), and immune thrombocytopenia (ITP), pose significant diagnostic and therapeutic challenges due to their heterogeneous presentations and complex underlying mechanisms. Traditional diagnostic methods rely on clinical assessments and laboratory tests, which can be time-consuming and prone to misdiagnosis, particularly in resource-limited settings. Artificial intelligence (AI) has emerged as a transformative tool in healthcare, leveraging machine learning (ML) algorithms and predictive analytics to enhance diagnostic accuracy, risk stratification, and personalized treatment approaches.ObjectiveThis systematic review explores the role of AI in the prevention, diagnosis, and management of bleeding disorders. Specifically, it assesses AI-driven models in identifying key predictors, optimizing risk assessment, and improving treatment outcomes.MethodsA comprehensive literature search was conducted across major databases following PRISMA guidelines. Studies were selected based on their focus on AI applications in bleeding disorders, particularly those utilizing ML models such as Random Forest, XGBoost, LightGBM, and deep learning techniques. The risk of bias was evaluated using the ROBINS-E and RoB 2 tools.ResultsTwelve studies met the inclusion criteria, demonstrating the efficacy of AI models in bleeding disorder management. Genetic markers, such as Factor VIII gene mutations and von Willebrand factor variants, enable early disease classification and severity prediction. Laboratory biomarkers, including baseline factor VIII activity, platelet count, and coagulation profiles, enhance risk assessment for bleeding complications. Clinical history variables, such as prior bleeding events, anticoagulant use, infection status, and comorbidities, support personalized treatment strategies. Additionally, demographic and environmental factors, including age, sex, healthcare utilization patterns, and socioeconomic status, refine predictive models for undiagnosed cases.ConclusionThe integration of these variables into AI-driven models has demonstrated superior diagnostic accuracy compared to traditional methods, facilitating early detection, individualized treatment planning, and improved patient outcomes. However, challenges such as dataset fragmentation, model interpretability, and limited external validation hinder widespread clinical adoption. AI-driven approaches have the potential to revolutionize bleeding disorder management by advancing precision medicine, optimizing healthcare resources, and promoting equitable access to high-quality care