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

Duration of low temperature storage, clove topping and gibberellic acid on garlic sprouting and seedling vigor

Dormancy of garlic (Allium sativum L.) creates a problem in use of freshly harvested garlic bulbs. Thus, pre-planting treatment of garlic cloves is an important agronomic concern for inducing and improving sprouting behavior of garlic. Glasshouse experiment was conducted at Haramaya University to evaluate the effect of cold storage (7°C) durations (10, 20, 30 days and one stored at room temperature that is 21°C for 30 days), clove topping (whole and cut) and gibberellic acid concentrations (0, 125, 250 and 375 mg/l) and distilled water treatment as second control on sprouting behavior of improved garlic variety (‘Tseday’). The treatments were laid out in factorial arrangement with three replications using completely randomized design (CRD). For cloves stored at ambient temperature (0 day) and non-topped, gibberellic acid application (250 and 375 mg/l) showed a significant increase in sprouting percentage, speed of sprouting and shoot dry mass of garlic as compared to 125mg/l GA3 treated and the controls. On the other hand, for topped cloves stored at ambient temperature (0 day), 10 and 20 days cold storage, gibberellic acid treatment did not show a significant influence on these characteristics as compared to the controls. The interaction effect of 30 days cold stored and topped cloves significantly increased pseudo-stem height (40.51%) compared to the lowest values recorded for the non-cold treated and non-topped cloves. The 30 days cold stored and topped cloves soaked in water significantly increased sprouting percentage over the period of 19 days after planting, speed of sprouting (four fold) and above ground shoot dry mass (79.41%) compared to the lowest values recorded for the non-cold treated and non-topped cloves not soaked in water and gibberellic acid (GA3). Hence, it can be concluded that 30 days cold storage, topping and soaking in water could enhance early sprouting of the garlic variety tested under glasshouse condition.Keywords: Clove topping, Dormancy, Garlic, Gibberellic acid, Sprouting percentage, Storage condition

Africa RISING science, innovations and technologies with scaling potential from postharvest management perspective

United States Agency for International Developmen

Relaxation oscillations and negative strain rate sensitivity in the Portevin - Le Chatelier effect

A characteristic feature of the Portevin - Le Chatelier effect or the jerky flow is the stick-slip nature of stress-strain curves which is believed to result from the negative strain rate dependence of the flow stress. The latter is assumed to result from the competition of a few relevant time scales controlling the dynamics of jerky flow. We address the issue of time scales and its connection to the negative strain rate sensitivity of the flow stress within the framework of a model for the jerky flow which is known to reproduce several experimentally observed features including the negative strain rate sensitivity of the flow stress. We attempt to understand the above issues by analyzing the geometry of the slow manifold underlying the relaxational oscillations in the model. We show that the nature of the relaxational oscillations is a result of the atypical bent geometry of the slow manifold. The analysis of the slow manifold structure helps us to understand the time scales operating in different regions of the slow manifold. Using this information we are able to establish connection with the strain rate sensitivity of the flow stress. The analysis also helps us to provide a proper dynamical interpretation for the negative branch of the strain rate sensitivity.Comment: 7 figures, To appear in Phys. Rev.

Prevalence and associated risk factors of malaria among adults in East Shewa Zone of Oromia Regional State, Ethiopia: a cross-sectional study

BACKGROUND: Malaria is one of the most important causes of morbidity and mortality in sub-Saharan Africa. The disease is prevalent in over 75% of the country's area making it the leading public health problems in the country. Information on the prevalence of malaria and its associated factors is vital to focus and improve malaria interventions. METHODS: A cross-sectional study was carried out from October to November 2012 in East Shewa zone of Oromia Regional State, Ethiopia. Adults aged 16 or more years with suspected malaria attending five health centers were eligible for the study. Logistic regression models were used to examine the effect of each independent variable on risk of subsequent diagnosis of malaria. RESULTS: Of 810 suspected adult malaria patients who participated in the study, 204 (25%) had microscopically confirmed malaria parasites. The dominant Plasmodium species were P. vivax (54%) and P. falciparum (45%), with mixed infection of both species in one patient. A positive microscopic result was significantly associated with being in the age group of 16 to 24 years [Adjusted Odds Ratio aOR 6.7; 95% CI: 2.3 to 19.5], 25 to 34 years [aOR 4.2; 95% CI: 1.4 to 12.4], and 35 to 44 years [aOR 3.7; 95% CI: 1.2-11.4] compared to 45 years or older; being treated at Meki health center [aOR 4.1; 95% CI: 2.4 to 7.1], being in Shashemene health center [aOR = 2.3; 95% CI: 1.5 to 4.5], and living in a rural area compared to an urban area [aOR 1.7; 95% CI: 1.1 to 2.6)]. CONCLUSION: Malaria is an important public health problem among adults in the study area with a predominance of P. vivax and P. falciparum infection. Thus, appropriate health interventions should be implemented to prevent and control the disease

Space-time analysis of reaction at RHIC

Space-time information about the Au-Au collisions produced at RHIC are key tools to understand the evolution of the system and especially assess the presence of collective behaviors. Using a parameterization of the system's final state relying on collective expansion, we show that pion source radii can be tied together with transverse mass spectra and elliptic flow within the same framework. The consistency between these different measures provide a solid ground to understand the characteristics of collective flow and especially the possible peculiar behavior of particles such as Xi, Omega or phi. The validity of the short time scales that are extracted from fits to the pion source size is also addressed. The wealth of new data that will soon be available from Au-Au collisions at sqrt{s_{NN}} = 200 GeV, will provide a stringet test of the space-time analysis framework developped in these proceedings.Comment: Invited talk given at the SQM2003 conference (March 2003), to be published in Journal of Physics G. 10 pages, 3 figure

Azimuthal anisotropy and correlations in the hard scattering regime at RHIC

Azimuthal anisotropy ($v_2$) and two-particle angular correlations of high $p_T$ charged hadrons have been measured in Au+Au collisions at $\sqrt{s_{NN}}$=130 GeV for transverse momenta up to 6 GeV/c, where hard processes are expected to contribute significantly. The two-particle angular correlations exhibit elliptic flow and a structure suggestive of fragmentation of high $p_T$ partons. The monotonic rise of $v_2(p_T)$ for $p_T<2$ GeV/c is consistent with collective hydrodynamical flow calculations. At \pT>3 GeV/c a saturation of $v_2$ is observed which persists up to $p_T=6$ GeV/c.Comment: As publishe