Hyperuniform disordered phononic structures

We demonstrate the existence of large phononic band gaps in designed hyperuniform (isotropic) disordered two-dimensional (2D) phononic structures of Pb cylinders in epoxy matrix. The phononic band gaps in hyperuniform disordered phononic structures are comparable to band gaps of similar periodic structures, for both out-of-plane and in-plane polarizations. A large number of localized modes is identified near the band edges, as well as, diffusive transmission throughout the rest of the frequency spectrum. Very high-Q cavity modes for both out-of-plane and in-plane polarizations are formed by selectively removing a single cylinder out of the structure. Efficient waveguiding with almost 100% transmission trough waveguide structures with arbitrary bends is also presented. We expand our results to thin three-dimensional layers of such structures and demonstrate effective band gaps related to the respective 2D band gaps. Moreover, the drop in the Q factor for the three-dimensional structures is not more than three orders of magnitude compared to the 2D ones

Intra-African Trade: Issues Involved in Improving Ghana's Trade with the Rest of Africa

This paper aims to find out why Ghana’s trade to Africa is low and how it can be improved. This is necessary because Ghana is looking at achieving middle income GDP per capita status by the year 2015 thereby reducing poverty and one of the ways proposed is through the increment in Ghana’s export volume. Thus in 2004, the government of Ghana developed the Ghana trade policy document to serve as a guide in achieving the goal. This paper focuses on the determinants of Ghana’s trade with other African countries through analysis of Ghana’s trade performance, the trade policy document of Ghana, Trade Cost and Regionalism[i]. An export equation is estimated using trade data on 49[ii] importing African countries using the gravity model. The result shows that the determinants of trade cost are very significant in explaining Ghana’s trade except tariff. Most importantly is that the improvement in the importers infrastructure will increase Ghana’s trade significantly. Also proper regional integration is very significant in increasing Ghana’s trade. Keywords: Trade, Trade Cost, Gravity Model, Regionalism Notes: [i] This focuses primarily of the Economic Community of West African States (ECOWAS) and how this regional body affects Ghana’s trade. [ii] Countries used are Algeria, Angola, Benin, Botswana, Burkina Faso, Burundi, Cameroon, Cape Verde, Central African Republic, Chad, Congo, Dem. Rep., Congo, Rep., Cote d'Ivoire, Djibouti, Egypt, Arab Rep., Equatorial Guinea, Ethiopia, Gabon, The Gambia, Guinea, Guinea-Bissau, Kenya, Lesotho, Liberia, Libya, Madagascar, Malawi, Mali, Mauritania, Mauritius, Morocco, Mozambique, Namibia, Niger, Nigeria, Rwanda, Sao Tome and Principe, Senegal, Seychelles, Sierra Leone, South Africa, Sudan, Swaziland, Tanzania, Togo, Tunisia, Uganda, Zambi

Students’ Consumption Determinants and Academic Performance Nexus: A Case Study of Private University Students in Ghana

The paper seeks to ascertain the factors that influence the private university student’s consumption and subsequent influence on academic performance. A linear model of the consumption function was used. The Ordinary Least Square technique was employed to determine the factors that influence students’ consumption. Following econometric procedures and data collected from field work; gender, marital status, age, average grade point, residential status, occupation, price levels, and disposable income were found to influence private university students’ consumption in Ghana. Also, from the correlation matrix, there is an inverse relationship between student’s performance and their consumption. The paper recommends redirection of students spending to impact on academic performance. Keywords: Academic Performance, Consumption, Ordinary Least Square, Students

Anti-tussive, muco-suppressant and expectorant properties, and the safety profile of a hydro-ethanolic extract of Scoparia dulcis

Background: Scoparia dulcis is used in Ghanaian folkloric medicine for the management of asthma and its related complications. This study was therefore aimed at evaluating the anti-tussive, muco-suppressant and expectorant properties of hydroethanolic extract of S. dulcis (SDE), and to ascertain its safety for use in asthma and obstructive pulmonary disease management.Methods: The number of coughs induced in guinea pigs using citric acid and the concentration of phenol red secreted in tracheae of mice were measured. Preliminary phytochemical analysis was conducted on the extract using standard procedures. Safety for use of the extract was assessed by conducting an acute and delayed toxicity test.Results: The extract showed a dose-independent inhibition (p ≤ 0.001) of cough elicited by 7.5% citric acid, and a dose-dependent increase (p ≤ 0.05) in the amount of phenol red output in mice tracheae similar to that of ammonium chloride. For the muco-suppressant activity, SDE dose-dependently reduced (p ≤ 0.001) the concentration of ammonium chloride-induced phenol red secretions from mice tracheae. Phytochemical screening showed the presence of tannins, alkaloids, glycosides, saponins, steroids, and phenolic compounds. No acute and/or delayed toxic symptoms were observed after an oral administration of up to 5 g/kg of S. dulcis extract.Conclusion: The results showed that S. dulcis extract has anti-tussive, muco-suppressant and, expectorant and/or mucolytic properties; making it a possible remedy for asthma, and obstructive pulmonary disease

Institutional voids, international learning effort and internationalization of emerging market new ventures

Much of the existing scholarly works portray institutional voids (IVs) in emerging economies as impeding forces against the development of new ventures. However, little attention has been paid to how such voids generate positive outcomes in emerging market new ventures. Drawing on the institutional theory, we propose IVs as crucial enablers of new venture internationalization. In addition, we investigate both how and when IVs enhance the degree to which new ventures internationalize by examining international learning effort (ILE) as a mediator and two domestic market environmental factors (i.e., environmental dynamism and competitive intensity) as important contingencies. We test our moderated mediation model using primary data gathered from 211 new ventures from Ghana. We found that ILE mediates the relationship between IVs and new venture internationalization and that both environmental dynamism and competitive intensity moderate the indirect relationship between home-country IVs and new venture internationalization. We discuss the theoretical and practical implications of this study

How organisational performance is affected by strategic corporate social responsibility (CSR)

This paper aims to report as a study that contributes to the understanding of the roles of strategic corporate social responsibility (CSR) in overall organisational performance. The approach to the paper was by the review of acclaimed researches with linkages between corporate social responsibility, more specifically strategic corporate social responsibility and organisational performance. Strategic CSR undertaken by various organisations were analysed to find how significant they affect to performance metrics. The researchers had difficulties unearthing previous tangential and empirical research as there had not been a wealth of research in the area of CSR relationships especially with regards to strategic CSR practices and performance and at the same time, previous research on CSR mostly focuses on its nature and impact on society and how customer loyalty can be gained with CSR. The study thus revealed that, although some organizations to some extent confuse CSR with philanthropic reasoning, they are aware of how rewarding it is for both societal stakeholders and the firm and intensively work towards integrating CSR with other business undertakings. This research contributes to one’s understanding of the impact that strategic CSR has on organisational performance when instituted in the business. Additionally, the study analyses how business performance may be affected either positively or negatively depending on the level of integration that strategic CSR has been implemented by organisations. The outcome of the study ultimately, will help top level management to amend shortcomings by implementing strategic CSR techniques as well as build formidable business performance.peer-reviewe

Antimicrobial and Anti-Inflammatory Activities of Pterygota macrocarpa and Cola gigantea (Sterculiaceae)

Pterygota macrocarpa and Cola gigantea are African medicinal plants used in traditional medicine for the treatment of sores, skin infections, and other inflammatory conditions including pains. This study therefore aims at investigating the antimicrobial properties of ethanol leaf and stem bark extracts of P. macrocarpa and C. gigantea using the agar diffusion and the micro-dilution techniques and also determining the anti-inflammatory properties of the extracts of these plants in carrageenan-induced foot edema in seven-day old chicks. The minimum inhibitory concentration of both ethanol leaf and bark extracts of P. macrocarpa against the test organisms was from 0.125 to 2.55 mg/mL and that of C. gigantea extracts was 0.125 to 2.75 mg/mL. Extracts with concentration of 50 mg/mL were most active against the test organisms according to the agar diffusion method. All the extracts of P. macrocarpa and C. gigantea at 30, 100, and 300 mg/kg body weight except ethanol leaf extract of C. gigantea exhibited significant anti-inflammatory effects (P ≤ 0.001)

Chief executive officers' sustainability orientation and firm environmental performance: Networking and resource contingencies

Although the existing literature supports the relationship between chief executive officers' (CEOs') sustainability orientation (SO) and entrepreneurial behaviour, empirical studies exploring how SO drives firm environmental performance (FEP) are lacking. In addition, the potential moderating effects of firm-level factors on this relationship are less understood. We contribute to filling this gap by examining the moderating effects of political connections and financial slack on the relationship between SO and FEP. Using data obtained from 297 small and medium-sized enterprises (SMEs) in Ghana, our results reveal that SO is positively related to FEP. In addition, our results show that the effect of SO on FEP is negative when firms have stronger financial slack and when firms are highly politically connected

Lower urinary tract symptoms suggestive of benign prostatic hyperplasia among Ghanaian men: a hospital-based cross-sectional prospective study

Background: Lower urinary tract symptoms (LUTS) of benign prostatic hyperplasia (BPH) are common in the elderly. This study sought to determine the prevalence of LUTS among patients visiting the urology clinic at Komfo Anokye Teaching Hospital, Kumasi, Ghana and to explore its presentation patterns.Methods: Simple randomized sampling technique was used to recruit 225 subjects with a mean age of 67.96±14.57 (range=40-100years) in a prospective cross-sectional study. LUTS related characteristics and international prostate symptom score (IPSS) questionnaire were employed to obtain relevant data.Results: The average IPSS of the studied participants was 17.52±7.83. Based on the IPSS, the prevalence of LUTS suggestive of BPH was 88.89%. Bladder storage symptoms were also recorded at 88.59% whilst prostate enlargement based on digital rectal examination (DRE) was 60.4% among the studied subjects.  PSA levels ≥4.0ng/ml gave a prevalence of 81.5%. The prevalence of prostate enlargement defined as PSA ≥1.5ng/ml was 85.23% among the studied subjects whilst 63.11% of the subjects examined had troublesome LUTS. Urgency was the most predominantly reported LUTS (93.3%) among the subjects studied.Conclusions: This study has clearly shown that, the most prevalent urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia were bladder storage symptoms and urgency. These symptoms when present clinically therefore, suggest benign prostatic hyperplasia and that the prevalence estimates of LUTS in older men are relatively higher at diagnosis.

Malaria elimination in Ghana:recommendations for reactive case detection strategy implementation in a low endemic area of Asutsuare, Ghana

Background: Progress toward malaria elimination is increasing as many countries near zero indigenous malaria cases. In settings nearing elimination, interventions will be most effective at interrupting transmission when targeted at the residual foci of transmission. These foci may be missed due to asymptomatic infections. To solve this problem, the World Health Organization recommends reactive case detection (RACD). This case study was conducted to identify individuals with asymptomatic malaria, their predisposing risk factors and recommend RACD in Asutsuare, Ghana based on literature review and a cross sectional study. Methods: The study involved a search on PubMed and Google Scholar of literature published between 1st January, 2009–14th August, 2023 using the search terms “malaria” in “Asutsuare”. Furthermore, structured questionnaires were administered to one hundred individuals without symptoms of malaria and screened using rapid diagnostic test (RDT) kits, microscopy and real-time polymerase chain reaction (rt-PCR). Malaria prevalence based on the three diagnostic techniques as well as potential malaria risk factors were assessed through questionnaires in a cross-sectional study. Results: Cumulatively, sixty-four (64) studies (Google Scholar, 57 and PubMed, 7) were reviewed and 22 studies included in the literature on malaria in Asutsuare, Ghana. Significant risk factors were occupation, distance from a house to a waterbody, age group and educational level. Out of the 100 samples, 3 (3%) were positive by RDT, 6 (6%) by microscopy and 9 (9%) by rt-PCR. Ages 5–14.9 years had the highest mean malaria parasite densities of 560 parasites/µl with Plasmodium falciparum as the dominant species in 4 participants. Moreover, in the age group ≥ 15, 2 participants (1 each) harboured P. falciparum and Plasmodium malariae parasites. RDT had a higher sensitivity (76.54%; CI95 66.82–85.54) than rt-PCR (33.33%; CI95 4.33–77.72), while both rt-PCR and RDT were observed to have a higher specificity (92.55; CI95 85.26–96.95) and (97.30; CI95 93.87–99.13), respectively in the diagnosis of malaria. Conclusion: In Asutsuare, Ghana, a low endemic area, the elimination of malaria may require finding individuals with asymptomatic infections. Given the low prevalence of asymptomatic individuals identified in this study and as repleted in the literature review, which favours RACD, Asutsuare is a possible setting receptive for RACD implementation.</p