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AbstractEight hundreds and eighty nine yeast strains were isolated from soils and wastes of palm oil mill and biodiesel plant in southern region of Thailand using glucose or glycerol as carbon source and at acidic condition (pH 4.0) or neutral condition (pH 6.0) with 0.0001% chloramphenicol. By applying Sudan Black B tests, 23 strains were identified as potential lipid producer or oleaginous yeast. The lipid contents of these 23 strains were compared in crude glycerol based medium. It was found that BY4-523 accumulated highest lipid content up to 53.28% while JU4-57 grew fastest and gave comparable high lipid content 41.50%. They were identified as Kodamaea ohmeri and Trichosporonoides spathulata, respectively. Among organic nitrogen sources tested, a mixture of yeast extract and peptone (1:1) gave the best biomass (17.05g/L for T. spathulata and 11.1g/L for K. ohmeri) and the maximum lipid production (10.43g/L for T. spathulata and 4.53g/L for K. ohmeri). In the view point of economic strategy, the cheaper inorganic nitrogen sources were also tested. Among inorganic nitrogen sources tested, ammonium sulfate was selected as a suitable nitrogen source. It gave the best biomass (9.17g/L for T. spathulata and 10.45g/L for K. ohmeri) and the maximum lipid production (3.85g/L for T. spathulata and 3.17g/L for K. ohmeri). The results showed that the newly isolated yeasts could grow and accumulate high lipid content in crude glycerol based medium supplemented with only ammonium sulfate. The optimal medium composition for both strains was 0.5% ammonium sulfate and 10% crude glycerol (C/N ratio of 17). Under this condition, the maximum biomass of 10.40g/L and lipid production of 4.45g/L were achieved for T. spathulata. Similarly, K. ohmeri also reached the maximum biomass of 10.50g/L and lipid production of 3.22g/L.

Adaptation to a repeated restraint stress schedule was monitored in ethanol-treated and control rats. A single episode of 2 h restraint decreased food intake in both control and ethanol-treated rats. The decreases in control rats were not observed following the 5th daily restraint of 2 h/day, suggesting that adaptation has occurred. Ethanol-treated rats, however, exhibited decreased food intake even after 5th daily restraint of 2 h/day. Ethanol administration decreased weekly but not daily cumulative food intake in unrestrained rats. Food intakes of ethanol-treated and control restrained rats were comparable following 1st-3rd daily restraints, but were smaller in ethanol-treated rats following the 4th and 5th daily restraints. Open-field ambulatory activities monitored 24 h after the 5th daily restraint on the 6th day were comparable in control restrained and unrestrained rats. Ethanol-treated and control unrestrained rats also exhibited comparable ambulation, but ethanol-treated rats exhibited smaller activity than control restrained or ethanol-treated unrestrained rats. Fluid intakes of ethanol and control rats were comparable during the 2 weeks of ethanol administration, but daily restraint schedule decreased ethanol intake. The findings show adaptation to repeated restraint in control rats and inability of ethanol-treated rats to adapt in the stress schedule. These findings imply that excessive alcohol consumption may impair adaptation to stress and thus conceivably precipitate depression.

Abstract The impact of CO 2 leakage from underground storage formations on shallow water resources is a concerning aspect in CO 2 capture and storage (CCS) risk assessment. In Campo de Calatrava region (Spain), natural CO 2 fluxes from the Earth’s mantle interact with shallow aquifers, resulting in significant changes in their physical and chemical properties. The resultant water is slightly acidic (pH 5.9-6.4), oxidizing, and enriched in iron (up to 6.1×10 -4 mol·L -1 ) and other metals usually found at trace concentrations. Thermodynamic calculations reveal that aqueous Fe(III) carbonate complexes play an important role in the persistence of this high concentration of iron and trace metals in solution.

The energy crisis and increasing fossil fuel prices due to increasing demands, controlled supplies, and global political unrest have adversely affected agricultural productivity and farm profitability across the globe and Pakistan is not an exception. To cope with this issue of energy deficiency in agriculture, the best alternate strategy is to take advantage of biomass and solid waste potential. In low-income countries such as Pakistan, the greenhouse heating system mostly relies on fossil fuels such as diesel, gasoline, and LPG. Farmers are reluctant to adopt greenhouse farming due to the continuously rising prices of the fossil fuels. To reduce reliance on fossil fuel energy, the objective of this study was to utilize biomass from crop residues to develop an efficient and economical biomass furnace that could heat greenhouses to protect the crop from seasonal temperature effects. Modifications made to the biomass furnace, such as the incorporation of insulation around the walls of the furnace, providing turbulators in fire tubes, and a secondary heat exchanger (heat recovery system) in the chimney, have increased the thermal efficiency of the biomass furnace by about 21.7%. A drastic reduction in hazardous elements of flue gases was observed due to the addition of a water scrubber smoke filter in the exit line of the flue. The efficiency of the biomass furnace ranged from 50.42% to 54.18%, whereas the heating efficiency of the diesel-fired heater was 71.19%. On the basis of the equal heating value of the fuels, the unit material and operating costs of the biomass furnace for wood, cotton stalks, corn cobs, and cow dung were USD 2.04, 1.86, 1.78, and 2.00 respectively against USD 4.67/h for the diesel heater. The capital and operating costs of the biomass furnace were about 50% and 43.7% of the diesel heater respectively, resulting in a seasonal saving of about 1573 USD. The produced smoke was tested as environmental friendly under the prescribed limits of the National Environmental Quality Standards (NEQS), which shows potential for its large-scale adoption and wider applications.

The developmental and behavioral effects of prenatal exposure to cocaine and/or ethanol were examined in rats. Pregnant rats received ethanol (E; 2 g/kg, b.i.d.) orally, cocaine (C; 6 mg/kg/day, IV), or both (C/E) on gestational days 8-20. Controls consisted of pair-fed (PF) and untreated (UNT) groups. Offspring were weighed and examined for developmental markers beginning postnatal day one (PD1). On PD21 pups were individually observed in an open-field following either an injection of cocaine (10 mg/kg, IP), an injection of saline, or no treatment. Drug-treated and PF dams ate less food and gained less weight than the UNT dams. C and E litters had slightly increased mortality rates. Pups from both the C and E groups appeared less sensitive to the locomotor stimulant effect of cocaine. Pups from the E group engaged in significantly less spontaneous stereotypic locomotion than UNT and PF pups, while male pups from the C group exhibited a decrease in spontaneous exploratory behavior. Thus, prenatal exposure to C or E altered spontaneous and/or cocaine-induced behavior in weanling-aged rats, while the C/E combination did not augment either effect.

Biogas production is a clean renewable energy source that can improve lives in developing countries. However, winter temperatures in some areas are too low to enable enough biogas production in small unheated digesters to meet the energy requirements of households. Low-cost, high yield reactors adapted to the local climate are needed in those situations. A decision-support model was developed to assist in the design of biogas reactors capable of meeting households’ year-round energy needs. Monthly biogas production relative to household energy needs was calculated for the scenario of suburban Hanoi, Vietnam. Calculations included pig number, slurry (manure water mixture) dilution, retention time and biogas/solar heating. Although using biogas to heat the digester increased biogas production, it did not lead to an energy surplus, particularly with the 1:9 slurry dilution rate commonly used on pig farms. However, at a 1:3 slurry dilution, the use of solar heating to provide 90% and biogas 10% of the heat required to heat the digester to 35 °C improved the biogas production by 50% compared to psychrophilic production. The energy needs of an average five-person family throughout the year required 17 fattening pigs. This model can establish the best solution for producing sufficient energy throughout the year.

It is increasingly acknowledged that climate change is influencing terrestrial ecosystems by increased drought and rainfall intensities. Soil microbes are key drivers of many processes in terrestrial systems and rely on water in soil pores to fulfill their life cycles and functions. However, little is known on how drought and rainfall fluctuations, which affect the composition and structure of microbial communities, persist once original moisture conditions have been restored. Here, we study how simulated short-term drying and re-wetting events shape the community composition of soil fungi and prokaryotes. In a mesocosm experiment, soil was exposed to an extreme drought, then re-wetted to optimal moisture (50% WHC, water holding capacity) or to saturation level (100% WHC). Composition, community structure and diversity of microbes were measured by sequencing ITS and 16S rRNA gene amplicons 3 weeks after original moisture content had been restored. Drying and extreme re-wetting decreased richness of microbial communities, but not evenness. Abundance changes were observed in only 8% of prokaryote OTUs, and 25% of fungal OTUs, whereas all other OTUs did not differ between drying and re-wetting treatments. Two specific legacy response groups (LRGs) were observed for both prokaryotes and fungi. OTUs belonging to the first LRG decreased in relative abundance in soil with a history of drought, whereas OTUs that increased in soil with a history of drought formed a second LRG. These microbial responses were spread among different phyla. Drought appeared to be more important for the microbial community composition than the following extreme re-wetting. 16S profiles were correlated with both inorganic N concentration and basal respiration and ITS profiles correlated with fungal biomass. We conclude that a drying and/or an extreme re-wetting history can persist in soil microbial communities via specific response groups composed of members with broad phylogenetic origins, with possible functional consequences on soil processes and plant species. As a large fraction of OTUs responding to drying and re-wetting belonged to the rare biosphere, our results suggest that low abundant microbial species are potentially important for ecosystem responses to extreme weather events.