CONTROLLING GROUND WATER DEGRADATION IN THE TULARE LAKE BASIN1

ABSTRACT This study examined the feasibility of extending the Accelerated Salt Transport (ASTRAN) method of groud water quality control to a complex, closed basin which is experiencing ground water quality degradation from irrigated agriculture (e.g., the Tulare Lake Basin in the Southern portion of the California Central Valley). A linear programming model was constructed and parametric analysis conducted which produced results with a “general appraisal” (or “level B”) degree of accuracy. The study concluded that a drainage water export drain is required in order to implement a long-term solution but that ground water degradation can be mitigated by a combination of the ASTRAN method and other measures even with existing entitlements and legal constraints.     

Exergy analysis of the transcritical N2O refrigeration cycle with a vortex tube

In this article, a comparative study is presented for the transcritical cycle with expansion valve (TCEV) and transcritical cycle with vortex tube (TCVT) mainly based on the second law of thermodynamics. Natural refrigerant nitrous oxide (N₂O) is used in both the cycles for analysis. The evaporator and gas cooler temperatures are varied from ?55°C to 5°C and 35°C to 60°C, respectively. The effects of various operating and design parameters on the optimum heat rejection pressure, coefficient of performance (COP), exergy loss (irreversibility), and the exergetic efficiency are studied. Exergy analysis of each component in TCEV and TCVT is performed to identify the amount and locations of irreversibility. It is observed that the use of the vortex tube in place of the expansion valve reduces the total exergy losses and increases the exergetic efficiency as well as COP. The exergetic efficiency and COP of the TCVT are on average 10–12% higher compared to TCEV for the considered operating conditions. The computed values of the exergetic efficiency for TCVT using refrigerant N₂O are the highest at an evaporator temperature of ?55°C, and the corresponding values of exergetic efficiency and exergy losses varies between 25.35% and 15.67% and between 74.65% and 84.33%, respectively. However, COP at the same evaporator temperature of ?55°C varies between 0.83 and 0.51. Furthermore, the optimum heat rejection pressure in TCVT is lower compared to that in TCEV. The results offer significant help for the optimum design and operating conditions of TCVT with refrigerant N₂O.     

Female philopatry and its social benefits among Bornean orangutans

Female philopatry in mammals is generally associated with ecological and sometimes social benefits, and often with dispersal by males. Previous studies on dispersal patterns of orangutans, largely non-gregarious Asian great apes, have yielded conflicting results. Based on 7?years of observational data and mitochondrial and nuclear DNA analyses on fecal samples of 41 adult Bornean orangutans (Pongo pygmaeus wurmbii) from the Tuanan population, we provide both genetic and behavioral evidence for male dispersal and female philopatry. Although maternally related adult female dyads showed similar home-range overlap as unrelated dyads, females spent much more time in association with known maternal relatives than with other females. While in association, offspring of maternally related females frequently engaged in social play, whereas mothers actively prevented this during encounters with unrelated mothers, suggesting that unrelated females may pose a threat to infants. Having trustworthy neighbors may therefore be a social benefit of philopatry that may be common among solitary mammals, thus reinforcing female philopatric tendencies in such species. The results also illustrate the diversity in dispersal patterns found within the great-ape lineage.     

Distribution of improved cook stoves: analysis of field experiments using strategic niche management theory

Close to three billion people globally and over 800 million in India are dependent on direct combustion of unprocessed solid biomass fuels in inefficient traditional mud stoves. Current cooking practices, besides causing serious health problems, are also being linked to emissions of climate change and pollution agents such as black carbon and ozone precursors. In India several initiatives have been taken up to tackle the problem but the present trajectory of limited technical and social change in cooking energy use is nonetheless persistent in rural areas. In order to develop and scale up alternative cooking technology options, we have analyzed, using the principles of strategic niche management, two projects implemented by The Energy and Resources Institute (TERI) in nine villages in India. The assessment, while highlighting reasons for stability of the current cooking regime, also points to triggers that can destabilize the regime. The focus is also on assessing the influence of protection in the form of subsidies on the process of transition. User preferences relating to social and technical aspects have been analyzed, pointing to forced draft cookstoves as the preferred option notwithstanding cost reductions to address affordability concerns. The assessment indicates that while it is critically important to understand and address the preferences of users and to improve the technology, scaling up will depend on stove cost reduction through further research. Creativity in effective financing schemes and support structures put in place by fostering public–private partnerships are also needed.     

Therapeutic applications of resveratrol nanoformulations

Resveratrol, or 3, 5, 4-trihydroxy-trans-stilbene, is a naturally occurring polyphenol present in several dietary sources such as grapes, soybeans, berries, pomegranate and peanuts. Resveratrol has received recent attention due to its diverse pharmacological activities. However, resveratrol clinical efficacy is limited due to its poor systemic bioavailability, of less than 1%, which is due to its low aqueous solubility, extensive first-pass metabolism and existence of enterohepatic recirculation. Therefore, in order to overcome these limitations, various nanocarriers including polymeric nanoparticles, solid lipid nanoparticles, liposomes, micelles and conjugates have been developed. These nanocarriers are able to enhance the bioavailability of resveratrol by modulating the P-glycoprotein, cytochrome P-450 enzymes and bypassing the hepatic first-pass effect. Here we review resveratrol nanoformulations for enhancing the efficacy of native resveratrol.     

Cyclodextrin-based delivery systems for dietary pharmaceuticals

Environmental Chemistry Letters - The food industry is increasingly seeking innovative solutions for enhancing the bioavailability and clinical efficacy of phytochemicals. In this regard,...     

Comparative assessment of pesticide residues in grain, soil, and water from IPM and non-IPM trials of basmati rice

The integrated pest management (IPM) modules of pesticide schedule on Basmati rice were validated at field experiments conducted in Northern India for consecutive 3 years (2005–2008). The pesticide residues were found below the detectable limit (<0.01–0.001 mg/kg) in soil and irrigation water samples of Kaithal region. In Dehra Dun region of Uttrakhand, the residues of carbendazim in rice grains and soil were detected below <0.01 mg/kg level. In second year experiments (2006–2007), only four non-IPM soil samples indicated the presence of chlorpyrifos and endosulfan in the range of ND <0.001 to 0.07 mg/kg, out of 45 samples analyzed. Carbendazim applied as seed treatment at Dehradun and Kaithal field trials was found below detectable limit in both IPM and non-IPM rice grains (<0.01 mg/kg) and irrigation water (0.01 μl/ml). Chlorpyrifos was detected in five water samples from Kaithal and one from Pant Nagar in the range of 0.003–0.006 μl/L, α- and β-isomer of endosulfan in the range of 0.005–0.03, and 0.005–0.02 μl/ml, respectively, in one sample from Pant Nagar and two from Kaithal, out of a total of 22 samples. In the region of Uttrakhand and Uttar Pradesh during 2007–2008, four non-IPM samples of soil indicated trace levels of endosulfan, out of 16 samples analyzed. The residues were detected below detection limit for carbendazim (<0.01 mg/kg) in soil samples of Dehradun IPM fields and for endosulfan and carbendazim (0.001–0.01 μl/L) in water samples each from IPM and non-IPM fields of Uttar Pradesh. The results of 3-year trials of IPM module indicated basmati rice as safe and economical with pesticide residue-free rice grains.     

Strength,durability, and microstructure of self-compacting geopolymer concrete produced with copper slag aggregates

Environmental Science and Pollution Research - Lack of vibrations on fresh concrete negatively influences the compaction and thus the quality of concrete. This is particularly concerning with...