Microstructural characterisation of TiAlTiAu and TiAlPdAu ohmic contacts to AlGaN/GaN

Ti/Al/Ti/Au and Ti/Al/Pd/Au contacts to AlGaN/GaN have been investigated to ascertain the effect of annealing temperature on the structural evolution of the contacts. Ti/Al/Ti/Au contacts become ohmic after rapid thermal annealing at 750°C or higher, corresponding to the formation of an interfacial TiN phase, with inclusions penetrating through the AlGaN layer observed after annealing at 950°C. The Pd layer is shown to be more efficient at inhibiting diffusion of Au to the interface than Ti. Ohmic behaviour was not seen with the Ti/Al/Pd/Au scheme. Either the presence of Au at the interface may improve ohmic behaviour, or the Ti:Al ratio is insufficient in this scheme

Interprofessional knowledge and perceptions of selected South African healthcare practitioners towards each other

Background. Interprofessional collaboration is internationally and popularly envisioned as a successful paradigm for the management of disease, disabilities and injuries. Despite this, the opinion of South African (SA) healthcare practitioners towards this idea is incoherent; this division of opinion needs to be changed to serve the common goal of better patient care.Objective. To provide a narrative overview of literature-based evidence of interprofessional knowledge and perceptions of SA doctors, nurses, physiotherapists, occupational therapists, dieticians, speech and hearing therapists, as well as biokineticists regarding interprofessional collaboration.Methods. An electronic search of Google Scholar, Crossref, PubMed and Sabinet databases identified 701 records, which were synthesised to 11 articles that were published during 2005 - 2016. Individual article quality was appraised using the modified Downs and Black scale.Results. Of the 11 records, 3 were Master’s theses reviewing the interprofessional knowledge and perceptions of doctors, physiotherapists and biokineticists towards the profession of chiropractic therapy; 3 examined the perceptions of chiropractic therapy, occupational therapy, speech and hearing therapy and biokinetics towards physiotherapy and chiropractic therapy; while the remaining 5 were supportive of interprofessional collaboration. The nature of the research designs of the selected studies were: survey (n=6), short communication (n=1), clinical commentary (n=1), randomised controlled trial (n=1) and focus group interview (n=2). An incoherence underlies the perceptions of the abovementioned practitioners regarding interprofessional collaboration owing to lack of interprofessional knowledge regarding each given discipline’s scope of profession (SoP). This is compounded by uneasiness with regard to patient competition. Some physiotherapists are against collaborative relationships, while occupational therapists, biokineticists and chiropractors are inclined to support the notion of a multidisciplinary physical rehabilitation team. There is a paucity of literature-based evidence reviewing the knowledge and perceptions of medical doctors, nurses and physiotherapists with regard to the SoP of occupational therapists, speech and hearing therapists, biokineticists, dieticians and chiropractors, thereby warranting future investigation.Conclusions. There are mixed perceptions of interprofessional collaboration among the selected healthcare practitioners owing to negative perceptions

Thiomorpholino oligonucleotides as a robust class of next generation platforms for alternate mRNA splicing

Recent advances in drug development have seen numerous successful clinical translations using synthetic antisense oligonucleotides (ASOs). However, major obstacles, such as challenging large-scale production, toxicity, localization of oligonucleotides in specific cellular compartments or tissues, and the high cost of treatment, need to be addressed. Thiomorpholino oligonucleotides (TMOs) are a recently developed novel nucleic acid analog that may potentially address these issues. TMOs are composed of a morpholino nucleoside joined by thiophosphoramidate internucleotide linkages. Unlike phosphorodiamidate morpholino oligomers (PMOs) that are currently used in various splice-switching ASO drugs, TMOs can be synthesized using solid-phase oligonucleotide synthesis methodologies. In this study, we synthesized various TMOs and evaluated their efficacy to induce exon skipping in a Duchenne muscular dystrophy (DMD) in vitro model using H2K mdx mouse myotubes. Our experiments demonstrated that TMOs can efficiently internalize and induce excellent exon 23 skipping potency compared with a conventional PMO control and other widely used nucleotide analogs, such as 2′-O-methyl and 2′-O-methoxyethyl ASOs. Notably, TMOs performed well at low concentrations (5–20 nM). Therefore, the dosages can be minimized, which may improve the drug safety profile. Based on the present study, we propose that TMOs represent a new, promising class of nucleic acid analogs for future oligonucleotide therapeutic development

Prevalence of Strongyle

Gastrointestinal parasitism is one of the major health problems affecting productivity of small ruminants worldwide. A dry season study was undertaken to determine the prevalence of Strongyle ova in goats and their faecal egg counts, as well as to compare different faecal culture methods for larval counts and identification. Out of 200 faecal samples examined, 114 were from male and 86 from female goats. An overall prevalence of 42(21%) for Strongyle ova was observed with a mean EPG of 91.67 + 6.12. The prevalence was higher in the male 26(22.8%) than in female 16(18.6%) with mean EPG of 90.38 ± 7.35 and 93.75 ± 11.06 respectively (p > 0.05). It was also higher in adults 38(22.22%) compared with the young 4(13.79%). All positive goats were of the Sahelian breed. No significant difference (p > 0.05%) was observed between sexes and age but a significant difference (p < 0.05) was observed between breeds. The infection was higher from samples collected in the abattoir 36 (25.35%) compared with 6(18.75%) in Mairi Village and none was positive from the University of Maiduguri Farm. A significant difference (p<0.05) was thus observed between locations. Only Strongyle ova was seen throughout the study and on subjection of the positive samples to larval recovery, Oesophagostomum columbianum was the only larva recovered. The test tube method yielded the highest larval recovery with mean larval count of 9.14 + 0.72 (p<0.05), compared with bottle with no charcoal; bottle with charcoal and Baermann’s techniques.Keywords: Goats, Strongyle ova, Faecal Culture Techniques, Prevalenc

Microstructural characterisation of TiAlTiAu and TiAlPdAu ohmic contacts to AlGaN/GaN

Ti/Al/Ti/Au and Ti/Al/Pd/Au contacts to AlGaN/GaN have been investigated to ascertain the effect of annealing temperature on the structural evolution of the contacts. Ti/Al/Ti/Au contacts become ohmic after rapid thermal annealing at 750°C or higher, corresponding to the formation of an interfacial TiN phase, with inclusions penetrating through the AlGaN layer observed after annealing at 950°C. The Pd layer is shown to be more efficient at inhibiting diffusion of Au to the interface than Ti. Ohmic behaviour was not seen with the Ti/Al/Pd/Au scheme. Either the presence of Au at the interface may improve ohmic behaviour, or the Ti:Al ratio is insufficient in this scheme

TEM studies of multilayer ohmic contacts to n-type AlGaN/GaN

Ti and Pd barrier layers between the Al/Ti diffusion couple and the Au capping layer of multilayer ohmic contacts to n-type AlGaN/GaN field effect transistors were found to be ineffective in preventing the diffusion of Au to the AlGaN following high temperature rapid thermal annealing. The formation of a band of TiN grains at the contact/AlGaN interface is responsible for the activation of the contact. The presence of interfacial Au and threading dislocations are implicated in the formation of additional Ti-nitride inclusions into the AlGaN, although these do not appear to disrupt the Ti-nitride layer at the original contact/nitride interface, nor significantly influence the contact resistance

Assessing beekeeping potential in Oyo State, Nigeria

This paper investigated the technical efficiency and its correlates as well as the profitability status of honey enterprise in Oyo State, Nigeria. A hundred and twenty respondents were sampled using multiple stage sampling techniques and questionnaire was administered to elicit the needed responses. The non-deterministic nature of producing honey informed the use of stochastic production model to assess beekeepers’ technical efficiency while gross margin analysis was adopted to illuminate how profitable honey production is in the area under consideration. The descriptive statistics revealed important socio-economic attributes of beekeepers in relation to beekeeping while the Maximum Likelihood Estimate (MLE) revealed the technical efficiency deciles of beekers within the production possibility frontier. Result revealed that beekeepers are operating close to the frontier of production using the available resources. The elasticity of production was greater than 1, showing an increasing return to scale of production while the budgetary analysis revealed that honey production is profitable. Consequent on the research outcome, beekeeping enterprise has the potential to generate substantial income, generate employment opportunity and meet the nutritional needs of Nigerian populace