Levels of essential and non-essential metals in Rhamnus prinoides (Gesho) cultivated in Ethiopia

The objective of this study was to assess the levels of essential and toxic metals in leaf and stem of Rhamnus prinoides which are used for bitterness of local alcoholic beverages in Ethiopia and as traditional medicine in some African countries. Levels of essential metals (Ca, Mg, Cr, Mn, Fe, Co, Ni, Cu and Zn) and toxic metals (Cd and Pb) in the leaves and stems of Rhamnus prinoides (Gesho) cultivated in Ethiopia were determined by flame atomic absorption spectroscopy. Known weights (0.5 g) of dried samples were digested with the optimized mixture of HNO3, H2O2 and HClO4 on a Kjeldahl apparatus with a reflux condenser. The efficiency of the optimized procedure was validated by spiking experiment and the percentage recovery for all the metals was in the range of 92–103% for leaf samples and 91–103% for the stem samples. The levels (mg/kg) of the metals were found to be: Ca (6304–22236), Mg (3202–5706), Cr (5.08–20.6), Mn (8.12–17.9), Fe (47.9–187), Co (22.2–42.1), Ni (12.8–27.3), Cu (6.5–73.0), Zn (12.2–43), Cd (0.81–3.10), and Pb (17.7–25.0) in the leaf samples and Ca (3601–5675), Mg (2635–5528), Cr (ND–16.3), Mn (2.16–3.98), Fe (22.0–124), Co (18.7–91.7), Ni (9.68–19.2), Cu (16.8–233), Zn (17.4–28.2), and Cd (ND–1.56) in the stem samples. However, the levels of Cr and Cd in stem samples at one and two sample sites, respectively, and the levels of Pb in stem samples at all sample sites were below the method detection limit. This study showed that the leaf and stem of R. prinoides (Gesho) are good sources of essential minerals and virtually free from toxic metal Cd but not from Pb in the leaf. KEY WORDS: Rhamnus prinoides, Gesho, Leaf, Stem, Minerals, Alcoholic beverages, Ethiopia Bull. Chem. Soc. Ethiop. 2012, 26(3), 329-342.DOI: http://dx.doi.org/10.4314/bcse.v26i3.

SHIGELLA DYSENTERIAE AND SH. FLEXNERI SEROTYPE PREVALENCE AND SEASONAL DISTRIBUTION IN ADDIS ABABA, ETHlOPIA

ABSTRACT A total of 945 Shigella strains were isolated from stool specimens received at the National Research Institute of Health, between January 1978 and I£cember 1985. Seven hundred and ftfty-two strains, belonging to Shigella dysenteriae and Sh. flexneri, were further identified to serotype level, and the results analysed in respect to their annual fluctuation over an 8-year period. Their seasonal distributon was also noted. Members of Sh. dysenteriae serotypes constituted 24.3% of total Shigella isolates. Within Sh. dysenteriae serotypes, type 1 followed by type 2 were dominant until 1984, when type 3 predominated. In 1985, types 1,2 and 3 were equally represented. Members of Sh. flexneri comprised 56.3% of total Shigella isolates. Unti11981, type 1 was dominant, followed by types 2 and 4, in that order. Since then, however, type 1 gave way to type 2, as the dominant Shigella flexneri serotype in Addis Ababa area. The internationally rare serotype 5 was encountered only once ,on 1981.Shigella infections were comparatively common during the months of April to June, and around the month of September. Its incidence was lowest at the height of the rainy season (July, August) and during the colder months of the year (December to january). The seasonal fluctuation of Shigella seemed to be influenced more by Sh. flexneri than by Sh. dysenteriae

Plasma-free amino acid response to changes in dietary protein in pregnant and non-pregnant Rhesus monkeys (Macaca mulatta)

The plasma free amino acid response to shortterm dietary isoealoric protein reduction was studied in tour non-pregnant and four pregnant rhesus monkeys (Mariam mulatm). Before the introduction of the protein-reduced diet. a general reduction of most plasma free amino acids was observed during pregnancy compared to the nonpregnant state. The pregnant and non-pregnant monkeys responded differently to the proteinreduced diet, suggesting different mechanisms ofcoping with dietary protein restriction. The pregnant monkeys showed a further reduction of Virtually all amino acids while on the protein reduced diet, but normalized these changes after return to the habitual diet. The non-pregnant monkeys showed a decrease in both the essential and non-essential amino acids and an increase in mainly the non~essential amino acids, while on the protein-reduced diet. The decrease was reverted and the increase continued on resumption of the habitual diet. This is probably the pattern of plasma-free amino acid changes that can be expected in primate studies involving both pregnant and non-pregnant Rhesus monkeys using an isocalorie protein-redueed diet

Seroprevalence of contagious caprine pleuropneumonia in Borana and Guji lowlands, Southern Ethiopia

A multistage cross sectional serological study and questionnaire survey were conducted on contagious caprine pleuropneumonia in selected districts of Borana and Guji lowlands, Southern Ethiopia, to determine the prevalence of the disease and identify risk factors associated with the occurrence of the disease. A total of 900 sera samples were collected and tested using Complement Fixation Test (CFT). Questionnaire surveys were conducted with 69 randomly selected households. Out of the 900 goat sera samples tested, 119 (13.2%) were seropositive for CCPP, giving an overall seroprevalence of 13.2 % (95% CI=11.0%-15.4%) in the study areas. A seroprevalence of 18.3% (95% CI=14.3%-22.7%), 11.7% (95% CI=8%-15.2%) and 9.7% (95% CI=6.3%-12.6%) were recorded in Liban, Teltale and Moyale districts respectively. The seroprevalence recorded in Liban district was significantly different from that of Moyale district (

Unsupervised feature learning for visual sign language identification

Prior research on language identification focused primarily on text and speech. In this paper, we focus on the visual modality and present a method for identifying sign languages solely from short video samples. The method is trained on unlabelled video data (unsupervised feature learning) and using these features, it is trained to discriminate between six sign languages (supervised learning). We ran experiments on video samples involving 30 signers (running for a total of 6 hours). Using leave-one-signer-out cross-validation, our evaluation on short video samples shows an average best accuracy of 84%. Given that sign languages are under-resourced, unsupervised feature learning techniques are the right tools and our results indicate that this is realistic for sign language identification

Speaker diarization using gesture and speech

We demonstrate how the problem of speaker diarization can be solved using both gesture and speaker parametric models. The novelty of our solution is that we approach the speaker diarization problem as a speaker recognition problem after learning speaker models from speech samples corresponding to gestures (the occurrence of gestures indicates the presence of speech and the location of gestures indicates the identity of the speaker). This new approach offers many advantages: comparable state-of-the-art performance, faster computation and more adaptability. In our implementation, parametric models are used to model speakers' voice and their gestures: more specifically, Gaussian mixture models are used to model the voice characteristics of each person and all persons, and gamma distributions are used to model gestural activity based on features extracted from Motion History Images. Tests on 4.24 hours of the AMI meeting data show that our solution makes DER score improvements of 19% on speech-only segments and 4% on all segments including silence (the comparison is with the AMI system)

VarClass: An open-source language identification tool for language varieties

This paper presents VarClass, an open-source tool for language identification available both to be downloaded as well as through a graphical user-friendly interface. The main difference of VarClass in comparison to other state-of-the-art language identification tools is its focus on language varieties. General purpose language identification tools do not take language varieties into account and our work aims to fill this gap. VarClass currently contains language models for over 27 languages in which 10 of them are language varieties. We report an average performance of over 90.5% accuracy in a challenging dataset. More language models will be included in the upcoming month

Application of video processing methods for linguistic research

Evolution and changes of all modern languages is a well-known fact. However, recently it is reaching dynamics never seen before, which results in loss of the vast amount of information encoded in every language. In order to preserve such heritage, properly annotated recordings of world languages are necessary. Since creating those annotations is a very laborious task, reaching times 100 longer than the length of the annotated media, innovative video processing algorithms are needed, in order to improve the efficiency and quality of annotation process

Classifying pluricentric languages: Extending the monolingual model

This study presents a new language identification model for pluricentric languages that uses n-gram language models at the character and word level. The model is evaluated in two steps. The first step consists of the identification of two varieties of Spanish (Argentina and Spain) and two varieties of French (Quebec and France) evaluated independently in binary classification schemes. The second step integrates these language models in a six-class classification with two Portuguese varieties