Assessing Soil Nutrient Additions through Different Composting Techniques in Northern Ethiopia

The use of vermi-compost in northern Ethiopia is not a common practice. It is, therefore, important to understand the possible impediments through studying its chemical and biological properties and its extra contribution compared to other composting techniques. Four compost types (vermi-compost, conventional compost, farmers’ compost and community nursery compost) with three replications were used in this study. The farmers’ and community nursery compost samples were collected from different places in Tigray; whereas, the vermi- and conventional composts were prepared at Mekelle University following a standard composting procedure. Six major composting materials were identified in the visited sites from farmers’ and community nursery foremen’s interview. These composting materials were also used for the vermi- and conventional composting. Twelve composite compost samples were taken for analysis of macro- and micro-nutrients. The results of the experiment showed that for all treatments, despite of having high content of total C (5.04 – 10.67%), the C/N ratio (12.19 – 12.22) was low. This suggests that as the C/N ratio is lower than the threshold (< 30), mineralization is faster, nutrients eventually become available and a large amount of N is lost. Soil pH, exchangeable Magnesium (ex.Mg), exchangeable Potassium (ex.P), available Phosphorus (ava.P), and Cation Exchange Capacity (CEC) showed significant differences among the different composting techniques. Among the selected compost types, ex.Mg, ex.Ca and av.P were higher for vermi-compost. The lowest was recorded in community nursery compost. The use of vermi-compost is, therefore, very helpful in terms of providing beneficial soil nutrients as compared to other compost types.Keywords: Conventional compost, Vermi-compost, farmers’ compost, Nursery compost, Macro-nutrients, Micro-nutrients

Study on gross pulmonary lesions in lungs of slaughtered animals and their economic importance in Tigray, Ethiopia

A cross-sectional epidemiological study on slaughtered cattle at Mekelle abattoir, Northern Ethiopia, was conducted from November 19, 2008 to February 21, 2009 to investigate the distribution and risk factors of pulmonary lesions. The pulmonary lesions and diseases were diagnosed on the basis of pathological findings. Out of the 1,148 slaughtered cattle examined, 990 (86.2%) had one or more lesions. The prevalence of pulmonary lesions in the slaughtered cattle varied among categories of the study variables. The most common lesions were congestion (38.5%), emphysema (36.3%), hydatidosis (18.3%), abscesses (7.1%) and verminous pneumonia (3.2%). The risk factors identified on statistical basis (p < 0.05) were fat in cattle in pulmonary congestion, old age (>7 years) and very lean cattle in pulmonary emphysema and pulmonary abscesses and young age (<7 years) in verminous pneumonia. A total of 990 lungs (86.2%) were condemned or partially trimmed due to pulmonary lesions with an economic loss of 7,920 Ethiopian Birrs (ET Birr). This loss was calculated from the mean retail local market price of cattle lung and the total number of lungs condemned during the study period. Annual economic lose due to lung condemnation, determined by considering annual slaughter rate of cattle and prevalence of lung lesions in the abattoir, was estimated to be 65,000 ET Birr (US$). Keywords: Pulmonary lesions, Cattle, Abattoir, Economic loss, Ethiopia

Bayesian estimation of one-parameter qubit gates

We address estimation of one-parameter unitary gates for qubit systems and seek for optimal probes and measurements. Single- and two-qubit probes are analyzed in details focusing on precision and stability of the estimation procedure. Bayesian inference is employed and compared with the ultimate quantum limits to precision, taking into account the biased nature of Bayes estimator in the non asymptotic regime. Besides, through the evaluation of the asymptotic a posteriori distribution for the gate parameter and the comparison with the results of Monte Carlo simulated experiments, we show that asymptotic optimality of Bayes estimator is actually achieved after a limited number of runs. The robustness of the estimation procedure against fluctuations of the measurement settings is investigated and the use of entanglement to improve the overall stability of the estimation scheme is also analyzed in some details.Comment: 10 pages, 5 figure