Modified Frechet distributions and their generalized families

The Frechet distribution is used for modeling extreme events. There are different approaches to developing statistical distributions which include  the use of translation methods, system of differential equations, quantile methods among others. Existing statistical distributions are also modified  or generalized to accommodate other different types of data and improve goodness of fit to data. Addition of extra parameter(s) is one approach  used for generalizing existing distributions such that the base distributions are embedded in the new generalized distributions. Some methods of  parameter induction were used to obtained families of generalized distributions. Parameter(s) were also introduced into the probability  distributions of the Frechet distribution to derive functions of its modified versions belonging to each of the generalized families derived. Further  study is recommended on some of the modified Frechet distributions and their generalized families

Evaluation of the Effects of Nanofluid on the Lubricity of Oil-based Mud

Nanofluids are applied where heat transfer, drag reduction, binding ability for sand consolidation and corrosion control is of utmost priority. This paper discusses the experimental work carried out on a pre-conditioned base fluid (ethylene glycol and ethanol) with silicon-oxide powder as a nanofluid to investigate the nanofluid effect on lubricity enhancement in the oil based mud. The lubricity test was carried out using Ofite EP lubricity tester which simulates the speed of rotation of drill pipe and the pressure with which the pipe bears against the borehole wall. The result shows that nanofluids prepared using ethanol and ethylene glycol exhibited different rheological behaviors. But ethylene glycol treated with nanoparticles and oil based mud treated with nanofluid shows improved lubricity coefficients that falls within the obtainable lubricity coefficient observed in oil-based mud. Increase in weight percent of the nanoparticles in ethylene glycol resulted into decrease in the lubricity coefficient for the oil-based mud. It has been found that the weight percent of the nanoparticles and the type of continuous phase (ethylene glycol or ethanol) have an important effect on the lubricity of the oil-based mud. From the results, it can be concluded that, there is a non-linearity relationship between lubricity coefficient and particle weight. Percent in the mud treated with Nanofluid. The lubricity reduction effect observed in pre-conditioned oil-based mud can be said to be as result of combined effect of both the nanoparticles and the based fluid

An international comparative study of blood pressure in populations of European vs. African descent

Background: The consistent finding of higher prevalence of hypertension in US blacks compared to whites has led to speculation that African-origin populations are particularly susceptible to this condition. Large surveys now provide new information on this issue. Methods: Using a standardized analysis strategy we examined prevalence estimates for 8 white and 3 black populations (N = 85,000 participants). Results: The range in hypertension prevalence was from 27 to 55% for whites and 14 to 44% for blacks. Conclusions: These data demonstrate that not only is there a wide variation in hypertension prevalence among both racial groups, the rates among blacks are not unusually high when viewed internationally. These data suggest that the impact of environmental factors among both populations may have been under-appreciated

Novel <i>IRF6 </i>mutations in families with Van Der Woude syndrome and popliteal pterygium syndrome from sub-Saharan Africa

Orofacial clefts (OFC) are complex genetic traits that are often classified as syndromic or nonsyndromic clefts. Currently, there are over 500 types of syndromic clefts in the Online Mendelian Inheritance in Man (OMIM) database, of which Van der Woude syndrome (VWS) is one of the most common (accounting for 2% of all OFC). Popliteal pterygium syndrome (PPS) is considered to be a more severe form of VWS. Mutations in the IRF6 gene have been reported worldwide to cause VWS and PPS. Here, we report studies of families with VWS and PPS in sub-Saharan Africa. We screened the DNA of eight families with VWS and one family with PPS from Nigeria and Ethiopia by Sanger sequencing of the most commonly affected exons in IRF6 (exons 3, 4, 7, and 9). For the VWS families, we found a novel nonsense variant in exon 4 (p.Lys66X), a novel splice-site variant in exon 4 (p.Pro126Pro), a novel missense variant in exon 4 (p.Phe230Leu), a previously reported splice-site variant in exon 7 that changes the acceptor splice site, and a known missense variant in exon 7 (p.Leu251Pro). A previously known missense variant was found in exon 4 (p.Arg84His) in the PPS family. All the mutations segregate in the families. Our data confirm the presence of IRF6-related VWS and PPS in sub-Saharan Africa and highlights the importance of screening for novel mutations in known genes when studying diverse global populations. This is important for counseling and prenatal diagnosis for high-risk families

Building Innovative Online Korean and Japanese Courses: A Pilot on Technology- Enhanced Curriculum Development

Our pilot project created blended/online courses to accommodate the growing needs of precollegiate and collegiate students interested in learning Korean and Japanese. In the initial phase, we conducted a survey of students’ experiences with and perceptions about blended/online Asian language learning. We found a general lack of familiarity with, and moderate resistance toward, online language learning modes. With learner attitudes in mind, we developed online modules for beginning Korean and Japanese courses. In this article, we report the survey results and the process of developing these innovative blended and online modalities of content delivery, focusing on the strengths of the modules and the unforeseen development challenges. The impacts that these technology-enhanced environments may have on student perceptions of transactional distance and tele-/copresence are explored. We suggest that transforming conventional East Asian language courses into blended/online modes is not only feasible but also beneficial for foreign language teaching and learning