Petrographic and geochemical characteristics of the Kiejo, Rungwe and Ngozi volcanic rocks, southern Tanzania: Implication for tectonic activities and magmatic differentiation

Rock samples were collected from the Kiejo, Rungwe and Ngozi volcanoes, southern Tanzania. Results show that, in the Ngozi and Rungwe volcanoes, magma cooled relatively fast. After large part of the magma had crystallized, nucleation of crystals at a relatively slow rate crystallized from interstitial fluids of the primary magma that had already crystallized fine grained minerals resulting into large grains of minerals. In the Kiejo volcano, both zoned and unzonned olivine crystals exist; unzoned crystals being primary and the zoned ones are secondary. Such observations also indicate that the magma responsible for these rocks had interstitial fluids that crystallized into olivine of different chemical and grain sizes.The lack of olivine, and the presence of orthopyroxene, the high amount of SiO2 wt% (~ 63) as well as (Na2O + K2O) wt% ~ 9.38 in the Ngozi volcano, indicate that the volcanic rocks in the Ngozi volcano are a result of a relatively silica saturated magma source. Otherwise, the magma could have originated from deeper in the crust such that it became contaminated with continental crust materials as it was erupting.Based on the Alikali-Silica diagram of Le Bas et al. (1986), the Ngozi and Rungwe magma contents fall in the field of trachy-dacite, and those from the Kiejo volcano fall in the field of basaltic trachy-andesite and basaltic magma. Such a pattern highlights close genetical and ?structural relationship of the magma that formed the three volcanoes.Keywords: Kiejo, Rungwe, Ngozi, volcanic rocks, Southern Tanzani

Evaluation procedures to predict the keeping quality of ultra-high temperature (UHT) processed skim milk

This study evaluated the ability of an improved carbon-14 protease assay as a rapid procedure to screen raw milk and predict the keeping quality of UHT processed skim milk. Raw milk composition and microbiological quality were evaluated as possible parameters which could determine the keeping quality of UHT processed skim milk. Protein, total solids, fat, free amino groups, standard plate count, psychrotrophic bacteria count, proteolytic bacteria count, somatic cell count, and initial protease activity (measured by the radioisotope procedure) were determined on 51 raw milk samples pooled from area farms. University farm and University creamery storage tank, which were then skimmed and UHT processed and held for 60 days at 25 C. The samples were analyzed for change in free amino groups upon coagulation or at 60 days whichever occured first. Viscosity was measured on a weekly basis except on the first two weeks. The samples which lasted 60 days were analyzed for bitterness by a panel of experienced judges. Shelf-life was determined as days to coagulation or 60 days, whichever was sooner. Shelf-life was weakly correlated to initial protease assay (r=.26: p= .06). Initial protease activity was inversely and weakly correlated to bitterness flavor score (r=-.27: p=.08). Shelf-life was also weakly and inversely correlated to somatic cell count(-.25: p= .08). However, initial protease activity was positively correlated to psychrotrophic bacteria count but not with other bacteria counts. Bacterial counts were correlated to each other and to somatic cell count. Change in free amino groups were inversely correlated to shelf-life (r=- .30; p= .03). Viscosity was weakly correlated with bitterness flavor (r=-.48; p=.05). The relationship between initial protease activity and shelf-life was not a dramatic one, thus a longer evaluating period Is recommended. However, the positive correlation between Initial protease activity and psychrotrophic bacteria count Is an Important finding and suggests the potential of radiolabeled protease assay for rapid enumeration of psychrotrophic bacteria

Towards a sustainable tilapia breeding program in Tanzania

A structured breeding program is an important step towards sustainable tilapia aquaculture in Tanzania. The aim of the thesis was to generate baseline information for the establishment of tilapia breeding program in Tanzania. In the first study of this thesis we determined the genetic diversity between and within local and exotic Nile tilapia (Oreochromis niloticus) and Rufiji strains (Oreochromis urolepis urolepis) in Tanzania. Strains of FETA, Victoria, Igunga and TAFIRI had low genetic variation ranging from 0.057 to 0.1 while Kunduchi, Karanga and Ruhila showed highest genetic diversity from 0.214 to 0.212. Strong genetic differentiation was revealed between Karanga and the closely related strains of FETA, Lake Victoria, and Igunga with values from 0.533 to 0.548. STRUCTURE analysis revealed highly admixture among Karanga, Kunduchi, and Ruhila strains while FETA, Victoria, Igunga and TAFIRI showed no admixture. Higher genetic variation was also revealed among Rufiji strains compared to exotic and local Nile tilapia strains. High FST values (0.6- 0.8) were observed between Rufiji strains and the local or exotic Nile tilapia strains. The second part of this thesis based on a common garden experiment where the different strains of tilapia were compared in two environments with differing salinity. Differences in growth performance for all body traits were significant among Nile tilapia strains (P< 0.001) and strains ranked differently across the two environments. In freshwater environment, Karanga strain ranked first while TAFIRI strain ranked last. Regarding brackish water environment, Igunga strain was ranked first and the Victoria strain ranked last. Heritability estimates for harvest weight were low in both freshwater (0.10) and brackish water (0.09) environments compared to weight at tagging. Genetic correlations were low (0.35) for harvest weight and families ranked differently across the two environments indicating the existence of substantial GxE. Our results suggest that some strains are better suited than others to form the basis of a selective breeding program of Nile tilapia in Tanzania. Base population for the breeding program needs to strike the right balance between picking the best performing strains and having a broad genetic basis. Caution though is needed due to the high GxE across the tested environments

Fear of Failure, Experience, and Division as Predictors of State Anxiety in Usfa Epee Fencers

Research looks for the sources of state anxiety for individual athletes prior to competition, which can be debilitating (Gould, 1993; Gould, Horn & Spreeman, 1983). Non-elite athletes who are high trait anxious (possibly fear of failure) have higher state anxiety than elite athletes (Conroy, 2002; Gould, Horn & Spreeman, 1983). Fencers may be prone to elevated state anxiety. No research links these variables together in fencing. The purpose of the study is to examine fear of failure, experience, and division as predictors of state anxiety for epee fencers prior to competition. Epee fencers (N = 145) who competed in the USFA Summer Nationals completed a demographics questionnaire, the Competitive State Anxiety Inventory-2R (Cox, Martens & Russell, 2003), and the Performance Failure Appraisal Inventory (Conroy, Willow, & Metzler, 2002). Multiple regression analyses revealed fear of failure as a predictor of cognitive anxiety (B = .44, p \u3c .001). Division I-A fencers are predictive of higher cognitive anxiety than Division I fencers (B = .20, p = .04). None were significant predictors for somatic anxiety. Experience was not associated with either cognitive or somatic anxiety

Long distance contribution to B−→K−K−π+B^- \to K^- K^- \pi^+, - a searching ground mode for new physics

The decay $B^- \to K^- K^- \pi^+$ has been sugested as a test for minimal supersymmetric standard model and for supersymmetric models with R-parity violating couplings, in view of its extreme smallnesss in the standard model. We calculate two long distance contributions to this decay, that associated with $DD$ and $D\pi$ intermediate states and that induced by virtual $D$, $\pi$ mesons. The branching ratio due to these contributions is $6 \times 10^{-12}$, which is somewhat smaller than the standard model short distance result, leaving this decay free for the search of new physics.Comment: 13 pages, 2 figures, revised versio

Weak phases γ\gamma and α\alpha from B+B^+, or B0B^0 and BsB_s decays

An improved flavor SU(3) method is presented for determining the weak angle $\gamma$ of the unitarity triangle using decay rates for $B^+\to K\pi, B^+\to K^+\bar K^0$ and $B^+\to \pi^+\eta$ (or $B^0\to K\pi$ and $B_s\to K \pi$), their CP-conjugate modes and the CP-averaged rate for $B^\pm\to\pi^\pm\pi^{0}$. Rescattering (color-suppressed) contribution in $B^+(B^0)\to K\pi$, for which an improved bound is obtained, is subtracted away. The only significant SU(3) breaking effects are accounted for in the factorization approximation of tree amplitudes. The weak angle $\alpha$ is obtained as a byproduct.Comment: 9 pages with 2 included eps figures; revised argument, taking into account the special shape of the amplitude quadrangle. An improved bound on rescattering effects is give

A follow-up study of the business graduates of Mary E. Wells High School, Southbridge, Massachusetts, with implications for curriculum revision

Thesis (Ed.M.)--Boston Universit

06141 Abstracts Collection -- Dynamically Reconfigurable Architectures

From 02.04.06 to 07.04.06, the Dagstuhl Seminar 06141 ``Dynamically Reconfigurable Architectures\u27\u27 was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available