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From Truman to Reagan: The Evolution of U.S. Nuclear Policy in the Cold War Context
Full text linkSince the beginning of the nuclear era, the United States' nuclear policy has exerted substantial influence on international security and the intricacies of the Cold War. This scholarly work analyzes the evolution of United States nuclear policy throughout the Cold War period, from the presidency of Harry Truman to that of Ronald Reagan. Ranging from President Harry Truman’s decisive deployment of atomic weapons to President Ronald Reagan’s dedication to modernization and arms reduction, successive administrations have adapted their strategic approaches in response to emerging threats, technological advancements, and changing diplomatic contexts. This paper offers a comprehensive qualitative analysis of the progression of U.S. nuclear policy from 1945 to 1988, scrutinizing presidential doctrines, arms control negotiations, and the persistent tension between deterrence and disarmament. The study synthesizes primary and secondary sources to underscore pivotal moments and strategic shifts, considering both American and Soviet perspectives. The research illustrates how nuclear policy has both influenced and reflected broader transformations in U.S. grand strategy, culminating in landmark treaties that contributed to the termination of the Cold War
Etat de connaissances du Banana Bunchy top Virus (BBTV) : Synthèse bibliographique
Full text linkBanana Bunchy Top Virus (BBTV) est l’un des virus les plus destructeurs des bananiers, causant Banana bunchy top desease (BBTD). Il entraîne des pertes économiques importantes et constitue une menace pour la sécurité alimentaire dans plusieurs régions du monde. Cette synthèse bibliographique nous montre que l’état de l’art du BBTV. Le BBTV appartient à la famille des Nanoviridae, genre Babuvirus. Il est composé d’un ADN monocatenaire constitué de 6 à 10 molécules ADN codant chacune pour une protéine ayant un rôle important dans le fonctionnement du virus. Les six composants du génome BBTV sont appelés ADN-R, ADN-N, ADN-S, ADN, ADN-M, ADN-C et ADN- U3. Il affecte toutes les parties du bananier, notamment les feuilles, le pseudotronc et les rejets, provoquant un nanisme de la plante, des stries vert foncé, des feuilles dressées comme un bouquet de fleur. Il peut occasionner des pertes allant jusqu’à 80 à 100% de une perte de production de la banane. Le BBTV est transmis principalement par un puceron, Pentalonia nigronervosa, qui transmet le virus de manière persistante et circulante. Il appartient à l’ordre des homoptères, à la famille Aphididae, et au genre Pentalonia. Son hôte principal est Musa spp., bien que d'autres plantes comme Enset puissent être affectées. Il se propage principalement par le puceron et le matériel de plantation conventionnel notamment les bulbes et les rejets qui contribuent à l’expansion de la maladie. Le BBTV peut être détecté par différentes techniques telles que les méthodes d’observations visuelles, sérologiques (ELISA); les méthodes moléculaires par des techniques d’amplification PCR; LAMP et RCA. Le BBTV se propage rapidement dans les zones où son vecteur est présent et où les rejets infectés sont échangés entre agriculteurs. Des conditions climatiques favorables, telles que l’humidité et les températures élevées, accélèrent la dispersion du virus. Le virus est présent dans près de 53 pays dans le monde. Avec une incidence de 38% pour l’Afrique, 32% pour l’Asie ; 28% pour l’Océanie et 2% pour l’Amérique. Il existe deux principaux groupes phylogénétiques: le groupe Pacifique-Océan Indien (PIO) et le groupe Asie du Sud Est (SEA). Les divers isolats de BBTV présente une homologie de plus 85%. Tous les isolats d’Afrique sont regroupés au niveau POI. La diversité génétique influence la virulence et la dissémination du virus. Pour protéger la culture du bananier, des mesures de gestion du BBTV peuvent être mise en place à plusieurs niveaux. Ces stratégies de gestion reposent sur (1) L’élimination des plants infectés pour éviter la propagation. (2) ; l’utilisation de matériel végétal sain et certifié ; (3) La lutte contre le puceron vecteur, notamment avec des insecticides ou des méthodes biologiques ; (4) La recherche de variétés résistantes par sélection génétique ou biotechnologie. Au Gabon, la présence du BBTV représente une menace croissante pour la production de bananes. Peu d’études approfondies ont été menées, mais les études menées ont révélé la présence du virus sur les 8 provinces parmi les 9 provinces. Des efforts sont nécessaires pour mieux cartographier sa présence, sensibiliser les producteurs et mettre en place des mesures de contrôle adaptées. Ce résumé met en évidence l’importance de la lutte contre le BBTV pour préserver la production bananière et garantir la sécurité alimentaire.
Banana Bunchy Top Virus (BBTV) is one of the most destructive viruses affecting banana plants, causing Banana Bunchy Top Disease (BBTD). It causes significant economic losses and poses a threat to food security in several regions of the world. This literature review provides an overview of the current state of knowledge on BBTV. BBTV belongs to the Nanoviridae family, genus Babuvirus. It consists of single-stranded DNA made up of 6 to 10 DNA molecules, each encoding a protein that plays an important role in the functioning of the virus. The six components of the BBTV genome are called DNA-R, DNA-N, DNA-S, DNA, DNA-M, DNA-C, and DNA-U3. It affects all parts of the banana tree, particularly the leaves, pseudostem, and suckers, causing dwarfism of the plant, dark green streaks, and leaves that stand upright like a bouquet of flowers. It can cause losses of up to 80 to 100% of banana production. BBTV is transmitted mainly by an aphid, Pentalonia nigronervosa, which transmits the virus persistently and circulantly. It belongs to the order Homoptera, the family Aphididae, and the genus Pentalonia. Its main host is Musa spp., although other plants such as Enset may also be affected. It spreads mainly through aphids and conventional planting material, particularly bulbs and suckers, which contribute to the spread of the disease. BBTV can be detected by various techniques such as visual observation, serological methods (ELISA), and molecular methods using PCR amplification techniques, LAMP, and RCA. BBTV spreads rapidly in areas where its vector is present and where infected suckers are exchanged between farmers. Favorable climatic conditions, such as humidity and high temperatures, accelerate the spread of the virus. The virus is present in nearly 53 countries worldwide. Its incidence is 38% in Africa, 32% in Asia, 28% in Oceania, and 2% in the Americas. There are two main phylogenetic groups: the Pacific-Indian Ocean (PIO) group and the Southeast Asia (SEA) group. The various BBTV isolates show more than 85% homology. All isolates from Africa are grouped at the POI level. Genetic diversity influences the virulence and spread of the virus. To protect banana crops, BBTV management measures can be implemented at several levels. These management strategies are based on (1) the elimination of infected plants to prevent spread; (2) the use of healthy, certified plant material; (3) control of the aphid vector, particularly with insecticides or biological methods; (4) research into resistant varieties through genetic selection or biotechnology. In Gabon, the presence of BBTV poses a growing threat to banana production. Few in-depth studies have been conducted, but those that have been carried out have revealed the presence of the virus in eight of the nine provinces. Efforts are needed to better map its presence, raise awareness among producers, and implement appropriate control measures
Effect of Regional Integration on Intra-Regional Informal Agricultural Trade in West Africa
Full text linkThis research, based on the gravity model, explores the complex relationship between regional integration and intra-regional informal agricultural trade in West Africa over the period 2010–2022. By assessing the major impact of the ECOWAS Common External Tariff (CET) and the gradual implementation of the African Continental Free Trade Area (AfCFTA), it reveals a paradoxical dynamic: despite institutional progress in regional integration, informal agricultural trade - largely driven by small-scale operators - remains insufficiently addressed in regional policies and strategies. The findings highlight a significant correlation between these integration initiatives and a marked decline in informal agricultural trade, thereby raising critical questions about the effective inclusion of these key actors in regional economic integration frameworks
Complexity of Electronic Marketing towards Performance of Gas Energy Companies in Tanzania: Insight from Innovation Diffusion Theory
Full text linkThe purpose of this study was to investigate the complexity of electronic marketing on the performance of gas energy companies in Tanzania with insight from Innovation Diffusion Theory. Data were gathered using a structured questionnaire sent to a convenience sample of 302 employees from Gas Company Tanzania Ltd, Taifa Gas Ltd, Lake Gas Ltd, Oryx Gas Ltd, and Pan African Energy Ltd. The study used an explanatory research design. Structural equation modelling was applied to data analysis to find the causal link between company performance and the complexity of electronic marketing. Results revealed quite a strong positive correlation between company performance measures and the complexity of electronic marketing. These results advise businesses in the gas sector to give training programme investments top priority in order to improve the simplicity of learning and application of electronic marketing tools. Organisations should also make sure staff can access structured learning opportunities and user-friendly systems. Reducing the entrance barrier for staff by means of simplified tool interfaces and consistent training can help to maximise their output in using electronic marketing solutions. Gas businesses should also concentrate on developing internal knowledge and encouraging a culture of appreciation for the advantages of electronic marketing. 
Shaping the Shift: Unpacking Uncertainties in change management for service delivery of Selected Commercial Banks in Nairobi City County, Kenya
Full text linkDue to evolving technologies, the banking industry faces increased pressure to meet corporate objectives, enhance productivity and profitability, control operational costs, reduce waste, and improve service delivery. Prolonged inadequate service delivery could be the reason behind the declining customer numbers and performance of Kenyan commercial banks, which have remained unchanged for the past five years. The primary goal of this study was to examine how various change management approaches affect service delivery at selected commercial banks in Nairobi City County, Kenya. This study aimed to examine a sample of commercial banks in Nairobi City County, Kenya, to find out how different methods affected their service delivery. These methods include leadership strategy, stakeholder participation strategy, communication strategy and planning strategy. The study was guided by three theories: stakeholder theory, path-goal leadership theory, and service quality theory. This study used a descriptive research design. The unit of observation consisted of the seven commercial banks in Kenya, together with the 314 individuals employed by these banks in the areas of finance, credit, marketing, and risk management. The approach of simple random sampling was used by the researcher to choose the respondents from each stratum. The total number of individuals sampled in the study was 176. To find out whether the questionnaires are reliable, comprehensive and easy to understand, a pilot test was carried out on 18 bank managers at SBM Bank. The investigation instrument's ultimate dependability was determined using Cronbach's alpha, which fell between the range of 0.7 and 1. Following the completion of the descriptive statistical analysis, tables were generated that displayed the frequency, mean, percentage, and standard deviation distributions. To assess the relationships and the impact of each independent variable on change management strategy, multiple linear regression was employed. The results indicated a strong positive significant correlation between leadership strategy, stakeholder engagement strategy, communication strategy, planning strategy and service delivery. The study concludes that effective leadership strategies enhance employee satisfaction and engagement, leading to improved service delivery, engaging customers through feedback mechanisms, surveys, and focus groups allows banks to understand their needs and preferences, effective communication strategies foster better engagement with customers, allowing banks to understand their needs and preferences and planning strategy aids in the optimal allocation of resources, including human, financial, and technological resources. The study recommends that banks should develop systems for collecting and analysing customer feedback to understand their needs and expectations. The banks should regularly gather feedback from customers, employees, and other stakeholders to understand their needs and expectations. The banks should recognize the various stakeholders involved, including customers, employees, regulators, and community members. The banks should conduct regular surveys and focus groups to understand customer needs, preferences, and pain points
Repérage de quelques difficultés des élevés du secondaire scientifique dans l’enseignement des sciences physiques
Full text linkLa didactique des sciences constitue un champ de recherche majeur visant à améliorer la qualité de l’enseignement et à réduire les obstacles à l’apprentissage. En particulier, les sciences physiques occupent une place centrale dans le système éducatif, tant en raison de leur importance scientifique que de leur rôle dans le développement des compétences analytiques et expérimentales. Cette recherche explore les difficultés rencontrées par les élèves marocains du secondaire scientifique dans l’apprentissage des sciences physiques et leurs répercussions sur la transition vers l’enseignement supérieur. Bien que la physique soit une science fondamentale, elle reste l’une des disciplines les plus redoutées, contribuant largement aux échecs observés dans les filières scientifiques. L’étude repose sur une enquête par questionnaire à choix multiples administrée à un échantillon de 300 élèves issus de lycées publics et privés répartis dans différentes régions du Maroc. Les résultats montrent que si la majorité des élèves connaissent globalement les objectifs de l’enseignement des sciences physiques, près des deux tiers ignorent les modalités d’évaluation. Les difficultés d’apprentissage sont principalement attribuées aux méthodes pédagogiques utilisées et au faible volume horaire. Par ailleurs, les élèves considèrent la discipline comme centrée sur les examens plutôt que sur ses applications réelles, même s’ils reconnaissent généralement son utilité. Plus de la moitié des participants estiment néanmoins que certaines parties du programme préparent à la poursuite d’études universitaires. Concernant les enseignants, les élèves expriment une préférence pour les professeurs masculins mais reconnaissent que, dans l’ensemble, les enseignants déploient des efforts pour faciliter la compréhension des notions. Face à ces constats, plusieurs pistes sont proposées : réviser et alléger le programme pour le rendre plus adapté à la transition secondaire–supérieur, renforcer les séances pratiques en laboratoire, intégrer les technologies de l’information et de la communication (TIC), et favoriser une pédagogie plus interactive. La conclusion souligne deux priorités : développer la formation continue des enseignants et accroître le volume horaire consacré aux sciences physiques. Ce travail contribue à enrichir la réflexion sur la didactique des sciences au Maroc et appelle à une meilleure articulation entre enseignement secondaire et supérieur.
The didactics of science constitute a major field of research aimed at improving the quality of teaching and reducing barriers to learning. In particular, physics occupies a central place in the educational system, both because of its scientific importance and its role in the development of analytical and experimental skills. This study explores the difficulties faced by Moroccan secondary school students in learning physics and their impact on the transition to higher education. Although physics is a fundamental science, it remains one of the most feared disciplines, contributing significantly to the failures observed in scientific streams. The research is based on a multiple-choice questionnaire administered to a sample of 300 students from public and private high schools across different regions of Morocco. The findings show that while most students generally understand the objectives of physics education, nearly two-thirds are unaware of the assessment methods. Learning difficulties are mainly attributed to the teaching approaches used and the limited number of instructional hours. Furthermore, students perceive the discipline as exam-oriented rather than focused on real-life applications, even though they generally acknowledge its usefulness. More than half of the participants nonetheless believe that certain parts of the curriculum prepare them for university studies. Regarding teachers, students express a preference for male instructors but acknowledge that, overall, teachers make efforts to facilitate the understanding of concepts. In light of these observations, several recommendations are proposed: revising and streamlining the curriculum to make it more suitable for the secondary-to-higher education transition, strengthening laboratory practice sessions, integrating information and communication technologies (ICT), and fostering more interactive pedagogy. The conclusion highlights two priorities: developing continuous teacher training and increasing the number of instructional hours devoted to physics. This work contributes to enriching the reflection on science didactics in Morocco and calls for better alignment between secondary and higher education
Determinants of Health Insurance Choice and Ownership in India-Evidence from National Sample Survey Data
Full text linkOut-of-pocket expenditure (OOPE) accounts for approximately 39% of total health expenditure in India and is on the rise. This is a matter of concern as high OOPE has impoverishing effects on the economy. Insurance serves as a cushion in the event of health-related distress and also helps consumers access the required quantity and better quality of care. Demand for insurance is a choice between risk and return that is contingent upon several socio-economic and demographic factors. The paper aims to identify the factors that influence the choice and ownership of health insurance in India. A multinomial logit model has been estimated using data on hospitalization published by the National Sample Survey Organisation, India (NSSO), 2014-15. Findings reveal that the presence of chronic ailments plays a significant role in the demand for health insurance. Other factors that not only shape demand but also influence the type of insurance chosen include education and income levels, household size and age of the individual. Government efforts have been crucial in reducing OOPE in India; however, better results can be expected with target-based innovative insurance products that offer greater coverage and transparency
Effect of Regional Integration on Intra-Regional Informal Agricultural Trade in West Africa
Full text linkThis research analyzes the effect of regional integration on informal intra-regional agricultural trade in West Africa[1], based on an augmented gravity model, over the period 2010–2022. It assesses the significant impact of the Common External Tariff (CET) of the Economic Community of West African States (ECOWAS) and the gradual implementation of the African Continental Free Trade Area (AfCFTA) on informal agricultural trade among West African countries. The results reveal a significant correlation between these integration initiatives and a marked decline in informal agricultural trade, thereby raising crucial questions about the effective inclusion of these key actors within regional economic integration frameworks.
[1] In this research, West Africa is defined as the ECOWAS countries, excluding Cape Verde
Literary Titles as Narrative Gateways: Exploring Novels, Drama, and Poetry
Full text linkTitles play a pivotal role in literature, serving as both a gateway and a symbolic microcosm of the narrative. This paper examines the role of literary titles as narrative gateways across various genres, including novels, drama, and poetry. By analyzing titles from plays, classic novels, and poetic works, the study explores how titles serve as entry points into the thematic and emotional landscapes of diverse literary forms. Through this exploration, the paper demonstrates the significance of titles in shaping reader expectations and enhancing the interpretive experience across different genres. This study categorizes literary titles into five distinct groups: descriptive titles, misleading titles, revelatory titles, titles borrowed from other literary works, and thematic titles. The study highlights how titles enhance narrative engagement, reflect thematic depth, and create intertextual connections. Through this classification, the paper emphasizes the aesthetic, philosophical, and interpretive dimensions of titles in literary fiction, offering insights into their enduring significance
El carbono orgánico en los suelos de Quintana Roo (México) bajo condiciones de vegetación natural
Full text linkQuintana Roo está situado en el sureste de México. Posee clima cálido subhúmedo; geológicamente es una zona kárstica muy diversa. Se presentan 14 grupos principales de suelos que sostienen 14 formaciones vegetales principales en buen estado de conservación. Los contenidos de carbono orgánico del suelo (COS) dependen de factores como el clima (temperatura y humedad) y la vegetación que crece sobre ellos. Las generalizaciones del contenido de COS en grandes extensiones no consideran la heterogeneidad edáfica y biológica de Quintana Roo. El objetivo de esta investigación fue determinar el contenido de COS en los primeros -30 cm de los diferentes grupos de suelo asociados a la vegetación mejor conservada. Se identificaron 40 puntos para muestreo de suelos en zonas con vegetación bien conservada. Los resultados muestran que Histosoles, Leptosoles Fluvisoles y Phaeozems tienen los mayores porcentajes de COS, el mayor contenido en Mg C ha-1 lo presentan los Histosoles, Nitisoles y Phaeozems; sin embargo, la superficie con estos tipos edáficos en Quintana Roo es muy pequeña; al contrario, los Leptosoles se encuentran presentes en siete de tipos de vegetación, y aunque con altos porcentajes de COS, no son aptos para almacenar carbono por su escasa profundidad y/o alta pedregosidad (mayor variabilidad). La selva baja subperennifolia crece en la mayoría de los suelos; pero los de selva baja espinosa inundable y de selva baja subperennifolia poseen más alto contenido de COS en Mg C ha-1. Los resultados muestran que, en condiciones naturales, el contenido de COS está condicionado por el tipo de suelo y las especies que conforman las asociaciones vegetales.
Quintana Roo is in southeastern Mexico. It has a warm, subhumid climate; geologically, it is a highly diverse karst area. Fourteen main soil groups are present, supporting fourteen well-preserved plant formations. Soil organic carbon (SOC) contents depend on factors such as climate (temperature and humidity) and the vegetation growing on them. Generalizations of SOC content across large areas do not consider the edaphic and biological heterogeneity of Quintana Roo. The objective of this study was to determine the SOC content in the top 30 cm of the different soil groups associated with the best-preserved vegetation. Forty soil sampling points were identified in areas with well-preserved vegetation. The results show that Histosols, Leptosols, Fluvisols, and Phaeozems have the highest percentages of SOC. Histosols, Nitisols, and Phaeozems have the highest Mg C ha-1 content; however, the area covered by these soil types in Quintana Roo is very small. In contrast, Leptosols are present in seven vegetation types and, although they have high percentages of SOC, they are not suitable for carbon storage due to their shallow depth and/or high stoniness (greater variability). Lowland semi-evergreen forest grows on most soils; however, lowland flooded thorn forest and lowland semi-evergreen forest have higher SOC contents in terms of Mg C ha-1. The results show that, under natural conditions, SOC content is influenced by soil type and the species comprising the plant assemblages