Finite element modeling of thermo-hydromechanically (THM) coupled problems in frozen ground engineering: state-of-the-art

Fully coupled Thermo-Hydro-Mechanical (THM) modeling has been widely studied in various areas of geomechanics, owing to the multiphase nature of geomaterials. Several researches have dealt with THM coupled modeling of geomaterials in high temperature regimes, but a limited work is available for geomaterials in low temperature regimes. A review and summary of existing work in the literature on THM coupled modeling of frozen soils is presented here. THM coupled modeling in general and its applications are pointed out. The basic governing equations of a coupled THM model in general form, namely mass, momentum and energy balance equations, are discussed. A review of fully coupled models is made and the numerical aspects of THM modeling are briefly discussed. A mechanical constitutive model makes up an important component of a fully coupled THM model and a brief review of existing constitutive models for frozen soils is presented. The models reviewed range from elastoplastic models to viscoplastic or creep and damage coupled models. Some models that consider different approaches from the plasticity framework are briefly reviewed. The state-of-the-art is summarized by pointing out the main aspects of THM coupled modeling and directions for future work

Population Status, Foraging and Diurnal Activity Patterns of Oribi (Ourebia ourebi) in Senkele Swayne’s Hartebeest Sanctuary, Ethiopia

The study on the population status, foraging behaviour and diurnal activity pattern of oribi (Ourebia ourebi) was carried out in Senkele Swayne’s Hartebeest Sanctuary from August 2005 to March 2006 during the wet and dry seasons. Direct observation on selected oribi groups was made to study activity patterns. Total count method was used in an area of 28 km2. The count of oribi in the study area ranged between 45 and 57 during the wet and dry seasons, respectively. There was no significant difference between the wet and dry season count (p>0.05). The sex ratio of adult males to females was 1.00:1.26. Oribi were mostly observed as solitary or in pairs, occasionally forming small groups. Oribi distribution showed preference to grazing on short grass (Themeda triandra) in each vegetation community. The distribution of oribi during the wet and dry seasons was similar in all vegetation communities. However, the tendency of population for wider distribution increased in the Pennisetum grassland. The annual mean proportion of daylight hours spent feeding by oribi was 54.7%. Morning and evening activity peaks were most obvious during the dry season, with most animals remaining inactive during the midday and hottest hours of the day. Large number of settled human communities in and around the Sanctuary and herds of livestock were frequently observed mainly during the wet season. Overgrazing and settlement encroachment are the major factors that could affect the population status of oribi by lowering the grass quality in the Sanctuary

Current Population Status of the Endangered Endemic Subspecies of Swayne’s Hartebeest (Alcelaphus buselaphus swaynei) in Maze National Park, Ethiopia

A study on current population status,  sex ratio and age structures of Swayne’s hartebeest (Alcelaphus buselaphus swaynei) was carried out during 2009/2010 in Maze National Park. Total count method was used in an area of 220 km2 using well trained park scouts based on silent detection. There were 372 individuals counted. The population trend indicates that there is a significant increase in the number of Swayne’s hartebeest population in Maze National Park at present. The sex ratio of adult males to adult females and young to adult females was 1:1.4 and 1:2.2, respectively. There is no significant difference between the sex ratio of males and females whereas there is a significant difference between young and adult females. Group size of Swayne’s hartebeest varied from solitary individuals to a maximum of 27. The difference among the groups is not significant. More solitary adult males were observed than solitary adult females. Swayne hartebeests were more associated with grassland with scattered trees (54%) than other three habitat types of the area, savannah grassland, bushland and riverine forest. There were no significant differences among the association of habitat types. Hartebeests were more associated to oribi (68%) than other ungulate species. There is an urgent need for further study to evaluate the actual threat of the endangered endemic subspecies of Swayne's hartebeests in Maze National Park

Do Academics Share Knowledge? Ethiopian Public Higher Education Institutions in Perspective

This study examines the knowledge sharing practices of academics in Higher Education Institutions(HEI) in Ethiopia. Based on the understanding that Knowledge Sharing is a key enabler of Knowledge Management, the study analyses how individual based variables determine knowledge sharing practices. The major relevant variables are drawn from the Theory of Planned Behavior. A survey instrument that has employed the conceptual framework was developed mainly from the extant literature in order to collect data from faculty of selected HEIs in Ethiopia. A quantitative approach of study will be employed to analyze the data obtained from the survey. Apart from providing a holistic perspective on the KS behaviors of faculty, based on the TPB model, the study intends to produce a validated and reliable instrument to measure KS

Sharing Thoughts

(No abstract

Proportion of Glaucoma among Voluntary People Coming for Glaucoma Screening Program at Jimma University Department of Ophthalmology, Jimma, Ethiopia

BACKGROUND: Glaucoma is the second leading cause of blindness worldwide. Glaucoma screening has been controversial, and much of the controversy has centered on the value of mass or community screening.METHODS: The aim of this study was to determine the proportion of glaucoma among volunteer adults who were screened in Jimma University Department of Ophthalmology. A cross-sectional study was conducted among 459 volunteer residents of Jimma town and surrounding areas. The study subjects were aged 40 years and above, who came for community screening program after media announcement during the four consecutive weekends of November 2014. Comprehensive eye examination was done including best corrected visual acuity, intra-ocular pressure measurement, stereoscopic optic nerve evaluation, angle structure evaluation and visual field testing. Three diagnostic criteria for glaucoma were employed for all cases.RESULTS: Of all adults who came for screening, 47(10.24%) were diagnosed to have glaucoma, 59(12.85%) were glaucoma suspects, and 8(1.74%) had ocular hypertension. The proportion of glaucoma increased with increasing age, (P value= 0.001 (99%CI)). Primary open angle glaucoma was the most common form (42.55%) of all new cases while 4.4% of all screened adults were followed by normal tension glaucoma (29.79%), pseudoexfoliative glaucoma (19.15%), and primary angle closure glaucoma (6.38%) Around 5.7% of all glaucoma cases were found to be blind.CONCLUSION: The proportion of glaucoma in this community screening program in Southwest Ethiopia was 10.24% with primary open angle glaucoma being the commonest subtype. Glaucoma community screening should be promoted for early diagnosis and intervention to prevent irreversible blindness

Pleurisy and bilateral pleural effusions after administration of atorvastatin

Atorvastatin is a widely used cholesterol-lowering agent. Although generally safe and well tolerated, a number of drug side effects have been reported. We report only the second case of atorvastatin-induced pleural effusions, presenting as pleurisy, and the first case from Ethiopia. We believe our patient had this association based on the temporal onset of symptoms, the otherwise negative evaluation, and the resolution of findings once atorvastatin was discontinued. Clinicians need to consider this relationship when evaluating unexplained pleurisy and pleural effusions in patients taking atorvastatin