Temporal and spatial expression of tissue inhibitors of metalloproteinases 1 and 2 (TIMP-1 and -2) in the bovine corpus luteum

The matrix metalloproteinases (MMPs) and their endogenous inhibitors, tissue inhibitors of metalloproteinases (TIMPs), may mediate the dramatic structural and functional changes in the corpus luteum (CL) over the course of its life span. In addition to regulating MMP activity, TIMPs are also involved in a variety of cellular processes, including cell proliferation and steroidogenesis. In a series of initial studies, we determined that matrix metalloproteinase inhibitory activity was present in protein extracts from early (4 days old, estrus = day 0), mid (10–12 days old) and late (16 days old) CL (n = 3 for each stage). Reverse zymography revealed four metalloproteinase inhibitory protein bands with relative Molecular masses that are consistent with those reported for TIMP-1 to -4. In order to gain a better understanding of TIMPs and their role in luteal function, we further characterized this inhibitory activity with a particular focus on the temporal and spatial expression of TIMP-1 and TIMP-2 in the bovine CL. Northern blotting revealed that the TIMP-1 transcript (0.9 kb) was expressed at a higher (p \u3c 0.05) level in early and mid cycle CL than in the late stage. In contrast, two TIMP-2 mRNA species, one major 1 kb species and one minor 3.5 kb species, were significantly (p \u3c 0.05) increased in the mid and late cycle CL than in the early. Western blotting analyses demonstrated no differences in TIMP-1 (29 kDa) protein levels between early and mid stages, while its levels decreased (p \u3c 0.05) from the mid to late stage CL. Conversely, TIMP-2 (22 kDa) protein was detected at a low level in the early CL, but significantly (p \u3c 0.05) increased in the mid and late stages. Immunohistochemistry revealed that both TIMP-1 and -2 were localized to large luteal cells from all three ages of CL. TIMP-1 was also localized in capillary smooth muscle cells, while TIMP-2 was restricted to the endothelial cells in the capillary compartment. In conclusion, the different temporal expression patterns of TIMP-1 and TIMP-2 suggest that TIMP-1 may be important for luteal formation and development, while TIMP-2 may play significant roles during luteal development and maintenance. Furthermore, the distinct localization of these two inhibitors in the vascular compartment indicates that they may serve diverse physiological functions during different stages of luteal angiogenesis

Innovating for skills enhancement in agricultural sciences in Africa: The centrality of field attachment programs

Africa remains an intensely agrarian continent, with two-thirds of its people directly or indirectly deriving their livelihood from agriculture. Higher agricultural education has thus emphasised production of graduates with the requisite skills to drive agricultural development. Despite these efforts, too few graduates in sub-Saharan Africa (SSA) have the employable skills necessary to transition to the labour market. A similar situation is observable among agricultural science graduates, who are vital to serving rural smallholder farmers. Most Colleges of Agriculture in Africa offer field attachment internships in agriculture and related fields but they are largely designed to cater for undergraduate students and are not part of the training programs at graduate level. To ameliorate this gap, the Regional Universities Forum for Capacity Building in Agriculture (RUFORUM), a network of 55 member universities in SSA, designed and rolled out an innovative field attachment program award (FAPA), launched in 2010, to serve graduate students. The FAPA is competitively based and designed to encourage students to follow through with the dissemination of their research and to enable them to link more closely with the communities and agencies working in the geographical area where the research was undertaken.During the period 2010–2015, five grant cycles were successfully implemented and 114 graduate students from 17 countries in SSA awarded. This article discusses the lessons learned during this period by examining two key areas: (1) the application process and implementation of the awards; and (2) the reported outcomes and challenges for grantees. Establishing the award has generated key technical and implementation lessons that the network and individual universities have been able to use to improve and institutionalise processes. Grantees have reported gaining a range of cross-cutting skills in personal mastery, initiative leadership and innovativeness, proactivity, flexibility, communication, analytical capacity, teamwork, networking and advocacy, and technical capacity, particularly in engaging with smallholder farmers. They have also noted significant challenges, in particular around establishing productive and sustainable engagement with smallholder farmers. These outcomes have influenced curricular reviews by member universities, with particular emphasis on these skills sets. Keywords: graduate employability, internships, sub-Saharan Africa, university

WhatsApp Usage in Administrative Processes of College of Distance Education, University of Cape Coast, Ghana

In Ghana, little is known about the educational values of WhatsApp usage as a multidimensional communication tool. WhatsApp usage is unguided and generally left in the hands of the juvenile for exploration.  This article established how WhatsApp application could promote administrative processes and support for the College of Distance Education (CoDE), University of Cape Coast, Ghana. The theories informing this study were adopted from the synthetic model of motivation (Turner, 1987) and Activity Theory by Vygotsky (1978). The descriptive cross-sectional survey design was used for the study. Data collection was quantitatively done with a questionnaire as the research instrument. Census technique was employed to gather data from all the 72 Study Centre Co-ordinators of CoDE. The two objectives and four hypotheses that guided the study were analysed with frequencies and percentages, ANOVA, independent sample t-test, and multiple standard regression. The study found that most of the respondents were satisfied with WhatsApp’s use to facilitate communication among stakeholders at CoDE. It further emerged that WhatsApp messaging enables rapid feedback among the key stakeholders (administrators, course tutors and students) of CoDE. However, few co-ordinators expressed disappointment regarding members sending irrelevant information and heavy videos sometimes in ungodly hours. It was recommended that enforceable user-guidelines and policies be made explicit for members to adhere to WhatsApp platforms’ use. Also, WhatsApp groups should be organised based on homogeneous interests while usage should be supported, regulated and promoted by the management of CoDE

Effects of Iron-Core Topology on Inrush Currents in Three-Phase Multi-Leg Power Transformers

This paper investigates the inrush currents of three-phase (a)symmetric multi-leg transformer cores considering magnetic core structure (e.g., three-leg vs. five-leg) and switching effects (e.g., recloser operating). The electromagnetic steady-state and transient behavior of three-phase transformers significantly differs from single-phase transformer operation mainly because of the unique flux coupling interactions in multi-leg and asymmetric core structures. A recently developed three-leg nonlinear transformer core model is applied to this study which considers the influence of magnetic hysteresis, flux couplings in the core-structure and nonsinusoidal operation in three-phase transformers. Simulations results for multi-leg (e.g., three-leg and five-leg) transformer cores demonstrating inrush current behavior based on the model are presented and discussed

Money Demand Function in Nigeria: Stability and Structural Breaks

This paper examined money demand function and its stability in Nigeria from 1970 to 2016. The study employed Robust Least Squares (RLS) regression method for the estimation of money demand function, while CUSUM and CUSUMSQ were used to examine the stability of money demand function. Multiple Breakpoints test approach was adopted to investigate structural breakpoints. The study found real income, interest rate, inflation rate, foreign interest rate as key determinants of money demand in Nigeria during the period covered by the study. Stability test revealed unstable money demand function and evidence of structural breaks in 1986, 1987, 1995, 1999, 2002, 2005, 2007 and 2008. This paper inferred that Central Bank of Nigeria should target broad money aggregates to control inflation in Nigeria. Also, in order to stabilize money demand in the country, the CBN should conduct monetary policy regime that focuses on stabilizing the real macroeconomic environment. Keywords: money demand function, stability, structural breaks, Robust Least Squares, Nigeri