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Judged by their negative nutrient balances, low soil cover and low productivity, the predominant agro-pastoral farming systems in the Sudano-Sahelian zone of West Africa are highly unsustainable for crop production intensification. With kaolinite as the main clay type, the cation exchange capacity of the soils in this region, often less than 1 cmolc kg−1soil, depends heavily on the organic carbon (Corg) content. However, due to low carbon sequestration and to the microbe, termite and temperature-induced rapid turnover rates of organic material in the present land-use systems, Corg contents of the topsoil are very low, ranging between 1 and 8 g kg-1 in most soils. For sustainable food production, the availability of phosphorus (P) and nitrogen (N) has to be increased considerably in combination with an improvement in soil physical properties. Therefore, the adoption of innovative management options that help to stop or even reverse the decline in Corg typically observed after cultivating bush or rangeland is of utmost importance. To maintain food production for a rapidly growing population, targeted applications of mineral fertilisers and the effective recycling of organic amendments as crop residues and manure are essential. Any increase in soil cover has large effects in reducing topsoil erosion by wind and water and favours the accumulation of wind-blown dust high in bases which in turn improves P availability. In the future decision support systems, based on GIS, modelling and simulation should be used to combine (i) available fertiliser response data from on-station and on-farm research, (ii) results on soil productivity restoration with the application of mineral and organic amendments and (iii) our present understanding of the cause-effect relationships governing the prevailing soil degradation processes. This will help to predict the effectiveness of regionally differentiated soil fertility management approaches to maintain or even increase soil Corg levels.

Many researches have reported that nucleic acid in coconut water is in free form and at very low yields which makes it difficult to process in molecular studies. Our research attempted to compare two extraction methods to obtain a higher yield of total RNA in aromatic coconut water and monitor its change at various fruit stages. The first method used ethanol and sodium acetate as reagents; the second method used lithium chloride. We found that extraction using only lithium chloride gave a higher total RNA yield than the method using ethanol to precipitate nucleic acid. In addition, the total RNA from both methods could be used in amplification of betaine aldehyde dehydrogenase2 (Badh2) genes, which is involved in coconut aroma biosynthesis, and could be used to perform further study as we expected. From the molecular study, the nucleic acid found in coconut water increased with fruit age.

Cryptomeria japonica (CJ) samples were heated in a thermogravimetric analyzer (TGA) with CO2 as agent to study the gasification kinetics in the isothermal process. The samples were torrefied at 250 and 350 °C for 1 h. before being tested in TGA. Three isothermal conditions of 750, 800, and 850 °C were tested in this study to estimate the kinetic parameters of the Arrhenius form with the proposed models. The homogeneous model (HM), shrinking core model (SCM), and linear model (LM) were used, and the predicted results obtained from these models were compared with experimental data. The reaction rate of gasification was enhanced as temperature was raised, and a correlation of kinetic parameters with temperature was obtained. The simulated results of the linear model (LM) fit well with experimental data. This work is useful for design gasification in downdraft gasifier.

The levels of production diseases (PD) and the cow replacement rate are high in dairy farming. They indicate excessive production demands on the cow and a poor state of animal welfare. This is the subject of increasing public debate. The purpose of this study was to assess the effect of production diseases on the economic sustainability of dairy farms. The contributions of individual culled cows to the farm’s economic performance were calculated, based on milk recording and accounting data from 32 farms in Germany. Cows were identified as ‘profit cows’ when they reached their individual ‘break-even point’. Data from milk recordings (yield and indicators for PD) were used to cluster farms by means of a principal component and a cluster analysis. The analysis revealed five clusters of farms. The average proportion of profit cows was 57.5%, 55.6%, 44.1%, 29.4% and 19.5%. Clusters characterized by a high proportion of cows with metabolic problems and high culling and mortality rates had lower proportions of profit cows, somewhat irrespective of the average milk-yield per cow. Changing the perception of PD from considering it as collateral damage to a threat to the farms’ economic viability might foster change processes to reduce production diseases.

With rising price of oil and other conventional fuels, world is turning towards renewable energy to enable it to meet the growing demand for electrical power requirements. As an option, solar photovoltaic (PV) is gaining popularity, though its high initial cost is a major barrier for its widespread use. It can supply electricity, as stand alone grid connected and isolated PV hybrid energy systems. This paper discusses the techno-financial feasibility study for an electrical power supply system for a rural (island) village. The design tool HOMER was used as the sizing and optimization tool. Solar radiation and related load information are the input data required, and the procedure has been applied to the island community of Kohjig, located in the gulf of Thailand.

Problem statement: In general, there are a number of rural dialects i n Thai. However, four dialects are mainly spoken by Thai people residing in four core region including central, north, northeast and south regions. Recognizing and synthe sizing Thai speech with different dialects are consequently difficult. Approach: Prosody is an important factor that must be taken into account, since the prosody effects on not only the naturalne ss but also the intelligibility of speech. To treat the problem, the speech prosody is carefully preserved through modeling the fundamental frequency (F0) contours. The differences among the model parameters of four Thai dialects have been summarized. This study proposed an analysis of model parameters for Thai speech prosody with four regional dialects and two genders which is a preliminary wor k for speech recognition and synthesis. Fujisaki's modeling; a powerful tool to model the F0 contour h as been adopted. Seven derived parameters from the Fujisaki's model are as follows. The first para meter is baseline frequency which is the lowest lev el of F0 contour. The second and third parameters are the numbers of phrase commands and tone commands which reflect the frequencies of surges of the utterance in global and local levels, respectively. The fourth and fifth parameters are p hrase command and tone command durations which reflect the speed of speaking and the length of a s yllable, respectively. The sixth and seventh parameters are amplitudes of phrase command and tone command which reflect the energy of the global speech and the energy of local syllable. Results: In the experiments, each regional dialect includes 200 samples of one sentence with male and female speech. Therefore our speech database contains 1600 utterances in total. The results show ed that most of the proposed parameters can distinguish four kinds of regional dialects explici tly. Conclusion: By using the Fujisaki's model, the results confirm that the proposed parameters can di stinguish the regional dialects efficiently. In the future research, they were expected to be applied i n the speech recognition and synthesis with various regional dialect characteristics.

ABSTRACTThermogravimetric analysis of raw (CJ-raw) and torrefied Cryptomeria japonica at 250°C (CJ-250) and 350°C (CJ-350) is performed in a pure CO2 environment on three heating rates of 10, 15 and 20°C/min. During pyrolysis, thermal decomposition occurred in three different stages: dehydration, hemicellulose-cellulose and lignin decomposition at 30.2–102.6°C, 222.6–422.1°C and 426–847.2°C, respectively. The simulated linear model fit quite well with the experimental data. A kinetic analysis of the raw and torrefied samples was also performed. In the main decomposition stage (the second stage), the activation energies of CJ-raw, CJ-250 and CJ-350 are 77, 114 and 50 kJ/mol, respectively. The highest activation energy (of CJ-250) is found to be due to the higher quantity of cellulose in the sample compared with other two samples. The activation energy of CJ-350 shows the lowest value because most volatiles in the hemicellulose–cellulose zone are expelled during the torrefaction process. A rising heating ra...