Convex Regularization Method for Solving Cauchy Problem of the Helmholtz Equation

In this paper, we introduce the Convex Regularization Method (CRM) for regularizing the (instability) solution of the Helmholtz equation with Cauchy data. The CRM makes it possible for the solution of Helmholtz equation to depend continuously on the small perturbations in the Cauchy data. In addition, the numerical computation of the reg- ularized Helmholtz equation with Cauchy data is stable, accurate and gives high rate of convergence of solution in Hilbert space. Undoubtedly, the error estimated analysis associated with CRM is minimal.Mathematics Subject Classi cation: 44B28; 44B30Keywords: Convex Regularization Method, ill-posed Helmholtz equation with Cauchy data, stable solutio

A Two-Dimensional Chebyshev Wavelet Method for Solving Partial Di erential Equations

In this paper, we introduce a two-dimensional Chebyshev wavelet method (TCWM) for solving partial di erential equations (PDEs) in L2(R) space. In this method, the spatial variables appearing in the PDE each has its own kernel, as well as wavelet coecient for approxi- mating the unknown solution of the equation. The approximated solu- tion of the equation is fast and has higher number of vanishing moments as compared to the Chebyshev wavelet method with only one wavelet coecient for two or more separated kernels for the variables appearing in the PDE

ANALYSING COCOA FARMERS' PERCEPTION ON THE USE OF PRINT MEDIA FOR EXTENSION DELIVERY IN ADANSI ASOKWA, GHANA

Community extension agents have been using various print materials like books, posters, flip charts, brochures, leaflets, newspapers, journals, magazines, and additional livelihood books to transfer improved agricultural technologies and information to cocoa farmers. However, the perception of farmers on these materials in aiding the adoption of innovations is unknown. A quantitative research approach was employed, and a structured questionnaire was used to collect data from 310 respondents. The study utilized both descriptive and inferential statistical techniques to achieve its research objectives. Results indicate that cocoa farmers perceive there are low levels of print media availability, utilization, preferability, and effectiveness. Despite the low perception of effectiveness, print media remains highly accessible to cocoa farmers and is a cost-effective method for delivering extension services. Its longevity and high engagement also contribute to its effectiveness. Factors such as household size, farm distance, marital status, years of cocoa cultivation, years of cooperative membership, economic activity, and educational level have a positive and significant influence on cocoa farmers' accessibility, utilization, and effectiveness of print media. Farmers are challenged by the infrequent and delayed delivery of print media. Agricultural agencies must therefore prioritize the timely delivery of print materials for extension activities to ensure that farmers can use them effectively

Growth inhibition of non-small cell lung cancer cells by AP-1 blockade using a cJun dominant-negative mutant

cJun, a major constituent of AP-1 transcription factor transducing multiple mitogen growth signals, is frequently overexpressed in non-small cell lung cancers (NSCLCs). The purpose of this study is to determine the effects of AP-1 blockade on the growth of NSCLC cells using a cJun dominant-negative mutant, TAM67. Transiently transfected TAM67 inhibited AP-1 transcriptional activity in NSCLC cell lines, NCI-H1299 (H1299), A549 and NCI-H520 (H520). The colony-forming efficiency of H1299 and A549 was reduced by TAM67, while that of H520 was not. To elucidate the effects of TAM67 on the growth of H1299, we established H1299 clone cells that expressed TAM67 under the control of a doxycycline-inducible promoter. In the H1299 clone cells, the induced TAM67 inhibited anchorage-dependent growth by promoting G1 cell-cycle block, but not by apoptosis. The induced TAM67 decreased the expression of a cell-cycle regulatory protein, cyclin A. TAM67 also inhibited anchorage-independent growth of these cells. Furthermore, TAM67 reduced growth of established xenograft tumours from these cells in nude mice. These results suggest that AP-1 plays an essential role in the growth of at least some of NSCLC cells

Examining the Relationship Among Socio-Demographic, Institutional Factors and Adoption of Best Tomato Production Practices in Southern Ghana

Tomato, an important staple in many Ghanaian homes, provides livelihood for many farming households. Despite its importance, farmers within major growing tomato districts are either unaware or have not adopted productivity enhancing tomato production practices. This paper examined the relationship between socioeconomic and institutional factors and the adoption of pre-emergence, post-emergence and filed management practices in the Ada West and Central Tongu districts. The study employed descriptive and inferential statistics such as frequencies, percentages, means, and chi-square test to describe the respondents and test of independence between farmer characteristics and adoption. The results revealed that the adoption rates of preemergence, post-emergence and field management practices were 48%, 50% and 64%, respectively. Factors such as farm size, education, farming experience, land tenure arrangements, access to extension services, access to credit and point of sale were found to be significantly associated with adoption of these practices. The main constraints to double season production were reported as unavailability of water and fluctuations in market demand. It is recommended that extension officers and researchers focus their dissemination messages on improved tomato production practices through appropriate channels and build farmers' capacity on the improved practices for enhanced food security and incomes of smallholder tomato farmers in Ghana

Adoption Potential of Improved Sweetpotato Varieties in Ghana

Root and tuber crops are essential staple crops produced in the West African sub- Region. The West African Agricultural Productivity Programme (WAAPP) funded by the World Bank seeks to improve root and tuber crops to ensure increased productivity, food security and poverty alleviation. The first phase ended with the release of four improved sweetpotato varieties (Ligri, Bohye, Dadanyuie, Patron) with higher productivity compared to other existing varieties. Potential adoption study is necessary to aid dissemination of the varieties by identifying varietal traits that could drive the adoption and varietal choices across various locations. The study employed qualitative approach (Participatory Rural Appraisal) involving 126 farmers randomly selected from a purposive pool of sweetpotato farmers from four major sweetpotato growing areas (Akatsi, Komenda, Ohawu and Asempanaye) in the Volta and Central regions of Ghana. Males (59.6%) dominated in sweetpotato production across location and a youth representation of 40% of the total sampled size which is a good indication for sweetpotato production. Sweetpotato production is undertaken mostly in the minor season (August-September) on an average farm size of 1.5 acres (0.6 ha) using both local and improved varieties (Sauti, Santom pona, Faara and Apomuden). Farmers perceived major pests that affected the crop to be Sweetpotato weevil (50% yield loss), Grasshoppers (30% yield loss) and Caterpillar (20% yield loss). Pesticides (Actelic 50 EC) was extensively used in pest control. Farmers perceived that, excessive use of pesticides had a negative effect on the sweetpotato yield and quality. Mean yield per hectare was 3.3 tons (3300 kg). Based on major and minor season prices, the highest profit was made in the minor season. Mean total production cost per hectare was GH₵1,925.00 in the major season and GH₵2,812.50 in the minor season; Revenues obtained were GH₵4,050.00 and GH₵6,600.00 and Gross Margins of GH₵2,125.00 and GH₵3,787.50 in the major and minor seasons respectively. Considering on absolute percentages, Komenda preferred variety Dadanyuie (85%) and Patron (62%); Ohawu preferred Bohye (85%) and Dadanyuie (76%), Asempanaye preferred Patron  (76%) and Bohye (70%);  Akatsi farmers preferred Dadanyuie (76%) and Bohye (61%) based on the varietal characteristics deemed ideal for farming conditions, increasing output and subsequently income. Optimum adoption of a new variety requires the consideration of locational variety choices, training on good agricultural practices, education on the traits of the new variety and proper marketing techniques. Keywords: Sweetpotato, Gross Margin, Varietal Choices, Adoption PotentialL'adoption Potentiel des variétés améliorées de patates douces au Ghana Les cultures de racines et tubercules sont des cultures de base essentielles produites dans la sous région de l'Afrique de l'Ouest. Le Programme de Productivité Agricole de l'Afrique de l'Ouest (PPAAO) financée par la Banque mondiale vise à améliorer les racines et les tubercules pour assurer une productivité accrue, une sécurité alimentaire et une réduction de la pauvreté. La première phase s'est terminée par le développement de 4 variétés de patates douces améliorées ('Ligri', 'Bohye', 'Dadanyuie', 'Patron') avec une productivité plus élevée par rapport aux autres variétés qui existent. Une étude d'adoption potentielle est nécessaire pour faciliter la diffusion des variétés en identifiant les traits variétals qui pourraient contribuer à l'adoption et les choix variétals dans divers endroits. L'étude a utilisé une approche qualitative (évaluation participative rurale) impliquant 126 agriculteurs sélectionnés au hasard parmi un groupe de cultivateurs de patate douce de quatre grandes zones de culture de la patate douce (Akatsi, Komenda, Ohawu et Asempanaye). Les hommes (59,6%) ont dominé la production de la patate douce à travers l'emplacement et une représentation des jeunes de 40% de la taille totale de l'échantillon, ce qui constitue une bonne indication pour la production de la patate douce. La production de la patate douce est plus faite dans la saison secondaire (août-septembre) sur une superficie moyenne de 1,5 hectare (0,6 ha) en utilisant des variétés locales et améliorées (Sauti, Santom pona, Faara et Apomuden). Les ravageurs majeurs qui ont affecté les cultures étaient le charançon de la patate douce (50% de perte de rendement), les sauterelles (30% de perte de rendement) et Caterpillar (20% de perte de rendement). Les pesticides (Acetelic 50EC) ont été largement utilisés dans la lutte antiparasitaire. Les agriculteurs ont perçu que l'utilisation excessive de pesticides avait un effet négatif sur le rendement et la qualité de la patate douce. Le rendement moyen par hectare était de 3,3 tonnes (3000 kg). Sur la base des prix de la saison majeure et de la saison secondaire, le bénéfice le plus élevé a été effectué dans la saison secondaire. Le coût total moyen par hectare était GH ₵ 1,925.00 dans la saison majeure et GH ₵ 2,1212.50 en saison secondaire; Les revenus obtenus ont été GH ₵ 4,050.00 et GH ₵ 6,600.00 et la marge brute étaient GH ₵ 2,125.00 et GH ₵ 3 787.50 respectivement. Komenda a préféré la variété Dadanyuie (85%) et Patron (62%); Ohawu préférait Bohye (85%) et Dadanyuie (76%), Asempanaye préférait Patron (76%) et Bohye (70%); Les agriculteurs d'Akatsi préféraient Dadanyuie (76%) et Bohye (61%) en fonction des caractéristiques variétales jugées idéales pour les conditions d'élevage, augmentant la production et par la suite les revenus. L'adoption optimale d'une nouvelle variété nécessite l'examen des choix de variété de localisation, la formation sur les bonnes pratiques agricoles, l'éducation sur les traits de la nouvelle variété et les techniques de marketing appropriées. Mots-clés: La patate douce, marge brute, choix variétals, l'adoption potentie

[In Press] A critical review of public–private partnerships in the COVID-19 pandemic : key themes and future research agenda

Purpose – Undoubtedly, coronavirus (COVID-19) pandemic has released unprecedented disruptions and health crisis on people and activities everywhere. The impacts extend to public–private partnership (PPP) arrangements in the construction industry. Concomitantly, PPP pacts are contributing to combat the pandemic. However, literature on the PPP concept in the COVID-19 era remain under-researched. This study aims to review the current literature on PPPs in the COVID-19 pandemic and present the key themes, research gaps and future research directions. Design/methodology/approach – In this study, 29 highly relevant literature were sourced from Web of Science, Scopus and PubMed search engines within the systematic literature review (SLR) methodology. With the aid of qualitative content analysis, the 29 articles were critically analysed leading to the extraction of hot research themes on PPPs in the coronavirus pandemic. Findings – The results of the SLR produced eight themes such as major changes in PPP contracts, development of the COVID-19 vaccines, economic recession, facemasks and testing kits, governance and sustainability of PPPs. In addition, the study reveals seven research gaps that need further investigations among the scientific research community on mental health and post-pandemic recovery plans. Research limitations/implications – The articles selected for this review were limited to only peer-reviewed journal papers written in English excluding conference papers. This restriction may have taken out some relevant literature but they had insignificant impact on the overall outcome of this research. Practical implications – To improve the understanding of practitioners in the construction industry on key issues on PPPs in the COVID-19 pandemic, the study provides them a checklist of relevant themes. Originality/value – As a novel literature review relating PPPs to the coronavirus, it sets the foundation for further research and contributes to practical measures to control the virus

Respiratory failure requiring mechanical ventilation in critically ill adults in Ghana: A prospective observational study

Introduction: Respiratory failure is commonly seen in African emergency centres and intensive care units, but little is known about the need for intubation and mechanical ventilation. Methods: From April to October 2017, we recorded the number of patients intubated and ventilated in the emergency centre and intensive care unit at Komfo Anokye Teaching Hospital in Kumasi, Ghana on a daily basis. We assessed patients for presence of acute respiratory distress syndrome (ARDS) using the Kigali Modification of the Berlin ARDS criteria. ARDS patients were re-assessed daily. Results: During the study period, 102 patients were intubated, of which 82 were assessed by the study team. The remaining 20 patients died before they could be assessed. Two (2.4%) patients were identified as having ARDS, and both died. Neither was treated with prone positioning or chemical paralysis. It is possible that many of the patients who died before an assessment suffered from ARDS, considering its associated high mortality, and thus the true incidence of ARDS may have been higher. Conclusion: Respiratory failure requiring intubation and mechanical ventilation is common in patients presenting to the emergency centre or intensive care unit at an academic tertiary care centre in Ghana. The true incidence of ARDS was likely underestimated by our study. Keywords: Respiratory failure, Respiratory insufficiency, Low-resource setting, Intubation, Mechanical ventilation, Ghan

Storage rot of seed yam resulting from speargrass injuries

Postharvest rot due to injury is a major contributing factor to the declining quality of stored seed yams (Dioscorea spp.). Among the several known injuries, the piercing effect of speargrass rhizomes has become a serious constraint for yam production in Ghana. The objective of this study was to assess injuries on seed yams resulting from piercing of speargrass rhizomes and their effects on postharvest rots in Ghana. Eighty farmer fields from Mem, Watro, Asanteboa and Abour in the Atebubu-Amantin Municipal in the Bono East Region of Ghana were screened for speargrass incidence and injury on harvested tubers, for laboratory analysis of pathogens in 2016 and 2017. The tubers were sorted into four categories of seed yam based on weight. Thirty seed yams each of two selected white yam cultivars (Dente and Kpamyo) with visible speargrass rhizome-pierced-tubers (VSRPT) and non- speargrass rhizome pierced healthy tubers (NSRPHT) were randomly selected and stored in a ban for weekly assessment of rot. The rotten tissues from the localised area of VPSRT were subjected to pathological investigations in the laboratory. The incidence of injury seemingly increased with increasing tuber weight. It was 0% for 1 kg samples, irrespective of cultivars and locations. Incidence of rot from NSRPHT sample was observed 5 weeks after storage (WAS) for both cultivars; and 2 WAS from the VSRPT sample and 40% higher than NSRPHT at 8 WAS. Eight and six known rot pathogens were isolated from the rotten tissues of VSRPT of Dente and Kpamyo, respectively. Injury from the piercing of speargrass rhizome significantly contributed to hastening of tuber rots; while tuber injury increased with increasing speargrass density. Appropriate management of speargrass is essential for commercial seed yam growers to reduce tuber damage which affects yam quality, storage and marketing