Water vortex hydropower technology: a state-of-the-art review of developmental trends

With the explosive growth of global energy demand coupled with effects of climate change, there is a significant shift towards green energy generation in recent years. Of the various renewable energy resources available, micro-hydro-power and pico-hydro-power remain very popular in both developed and developing countries. Since 2006, significant growth has spurted in the use of artificial free-surface vortices to generate low and ultra-low-head hydropower following the development of the so-called gravitational water vortex hydropower plant. The technology works on the principle of harnessing hydroelectric power from the high angular velocity experienced in the core of a whirlpool generated in a vortex chamber. In this article, a state-of-the-art review is undertaken on the vortex hydropower technology including a historical review of the technology, the underlying hydraulic principles of such devices, overview of research and technologies that have been deployed to date together with an evaluation of their performance and key findings. Currently, there are 19–22 known live vortex hydropower technologies operating internationally with key academic and commercial research activity in Europe and Asia. The average efficiency from these sites was found to be in the region of 53% which is lower than conventional propeller turbines but higher than waterwheel systems. It was found that the vortex plant, due to its ability to sustain relatively high efficiencies at low heads and small to medium flow rates, addresses a gap in the current turbine application chart. Its key advantage lies in the high-power densities produced compared with conventional technologies. The system also demonstrates potential to be able to function as a fish passage; however, stronger validation is required to prove this for a range of turbine systems. Finally, the authors propose a number of areas that should be investigated that should provide immediate improvements to the turbine in terms of performance.     

Electro‐membrane process for the separation of amino acids by iso‐electric focusing

BACKGROUND: Amino acids (AAs) are usually produced commercially using chemical, biochemical and microbiological fermentation methods. The product obtained from these methods undergoes various treatments involving extraction and electrodialysis (ED) for salt removal and AA recovery. This paper describes an electro‐membrane process (EMP) for the charge based separation of amino acids. RESULTS: Iso‐electric separation of AAs (GLU–LYS) from their mixture, using ion‐ exchange membranes (IEMs) has been achieved by an efficient and indigenous EMP. It was observed that electro‐transport rate (flux) of glutamic acid (GLU) at pH 8.0 (above its pI) was extremely high, while that for lysine (LYS) (pH 9.6) across the anion‐exchange membrane (AEM) was very low, under similar experimental conditions. Under optimum experimental conditions, separation of GLU from GLU–LYS mixture was achieved with moderate energy consumption (12.9 kWh kg^?1), high current efficiency (CE) (65%) and 85% recovery of GLU. CONCLUSIONS: On the basis of the electro‐transport rate of AA and membrane selectivity, it was concluded that the separation of GLU–LYS mixture was possible at pH 8.0, because of the oppositely charged nature of the two amino acids due to their different pI values. Moreover, any type of membrane fouling and deterioration in membrane conductivity was ruled out under experimental conditions. This work clearly demonstrates the great potential of EMP for industrial applications. Copyright © 2010 Society of Chemical Industry     

Lipid,protein and fatty acid profiles of Emericella sp. in different media

The soil‐derived fungus Emericella sp. was explored for its potential to produce lipid. Lipid profile, fatty acid composition, production of proteins and carbohydrates from lipid‐extracted biomass were determined. The effects of variations in the contents of carbon sources (glucose, dextrose), the salt content (NaCl) and the growth period were studied. A study on the effect of different growing media on the above‐mentioned parameters was also carried out. Although the maximum amount of lipid (6.14 ± 0.42 g/L) and protein (5.99 ± 0.47 g/L) was produced after 13 days in medium A containing 10% wt/vol glucose, the optimum lipid (2.90 ± 0.21 g/L) and protein (3.23 ± 0.28 g/L) production was observed in 2% wt/vol glucose medium considering the glucose content in the medium. The principal fatty acids found were 16:0 (14.4 ± 1.0 to 24.5 ± 2.4 wt‐%), 18:0 (12.1 ± 0.4 to 27.7 ± 2.7 wt‐%), 18:1 (13.5 ± 2.1 to 25.2 ± 2.8wt‐%) and 18:2 (30.9 ± 2.0 to 47.0 ± 2.8 wt‐%). Some of the lipids, especially those grown for 7 days in less glucose‐containing (1 and 2% wt/vol) medium were found to contain nearly 9.0 wt‐% of long‐chain PUFA 18:4, 20:4, 20:5, 22:4, and 22:5).     

Vision guided manipulation for planetary robotics — position control

Manipulation systems for planetary exploration operate under severe restrictions. They need to integrate vision and manipulation to achieve the reliability, safety, and predictability required of expensive systems operating on remote planets. They also must operate on very modest hardware that is shared with many other systems, and must operate without human intervention.Typically such systems employ calibrated stereo cameras and calibrated manipulators to achieve precision of the order of one centimeter with respect to instrument placement activities. This paper presents three complementary approaches to vision guided manipulation designed to robustly achieve high precision in manipulation. These approaches are described and compared, both in simulation and on hardware.In situ estimation and adaptation of the manipulator and/or camera models in these methods account for changes in the system configuration, thus ensuring consistent precision for the life of the mission. All the three methods provide several-fold increases in accuracy of manipulator positioning over the standard flight approach.     

The amino acid sequences in the C-terminal region of glucose-1-phosphate thymidylyltransferases determine their soluble expression in Escherichia coli

Two similar genes, dnmL and rmbA in Streptomyces peucetius, which encode for glucose-1-phosphate (G-1-P) thymidylyltransferases were expressed in Escherichia coli under similar conditions. While RmbA was expressed in soluble form, DnmL was found as insoluble aggregates in inclusion bodies. The difference in expression of these similar proteins led to investigate into the amino acid sequences of these proteins by sequence alignment, hydrophobicity scale and homology modeling. These analyses showed that the two proteins are different only in the C-terminal sequences. Deletion of C-terminal sequence of DnmL increased the expression level of truncated DnmL. Substitution of C-terminal sequence of DnmL with RmbA also expressed the recombinant protein in soluble form. Finally, mutation of six amino acids in DnmL rendered the protein expressed in soluble form. These results suggested that the soluble expression of the thymidylyltransferases lies in the C-terminal sequences. In conclusion, these methods of protein engineering will be a rational tool for enhancing solubility of proteins expressed in E.coli.     

Maternal Working Conditions and Child Well-Being in Welfare-Leaving Families.

In the wake of welfare reform, thousands of low-income single mothers have transitioned into the labor market. In this article, the authors examine how the work conditions of mothers leaving welfare for employment are associated with the emotional well-being of 372 children ages 5 to 15 years. The authors examine the cumulative incidence, over a 5-year period, of maternal non-family-friendly work conditions, including long work hours, erratic work schedules, nonday shifts, and lengthy commute times, in association with children's internalizing and externalizing behavior problems and levels of positive behavior. The authors found that mothers' lengthy commute times are associated with higher levels of internalizing problem behaviors and lower levels of positive behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rapamycin Alternatively Modifies Mitochondrial Dynamics in Dendritic Cells to Reduce Kidney Ischemic Reperfusion Injury

Dendritic cells (DCs) are unique immune cells that can link innate and adaptive immune responses and Immunometabolism greatly impacts their phenotype. Rapamycin is a macrolide compound that has immunosuppressant functions and is used to prevent graft loss in kidney transplantation. The current study evaluated the therapeutic potential of ex-vivo rapamycin treated DCs to protect kidneys in a mouse model of acute kidney injury (AKI). For the rapamycin single (S) treatment (Rapa-S-DC), Veh-DCs were treated with rapamycin (10 ng/mL) for 1 h before LPS. In contrast, rapamycin multiple (M) treatment (Rapa-M-DC) were exposed to 3 treatments over 7 days. Only multiple ex-vivo rapamycin treatments of DCs induced a persistent reprogramming of mitochondrial metabolism. These DCs had 18-fold more mitochondria, had almost 4-fold higher oxygen consumption rates, and produced more ATP compared to Veh-DCs (Veh treated control DCs). Pathway analysis showed IL10 signaling as a major contributing pathway to the altered immunophenotype after Rapamycin treatment compared to vehicle with significantly lower cytokines Tnfa, Il1b, and Il6, while regulators of mitochondrial content Pgc1a, Tfam, and Ho1 remained elevated. Critically, adoptive transfer of rapamycin-treated DCs to WT recipients 24 h before bilateral kidney ischemia significantly protected the kidneys from injury with a significant 3-fold improvement in kidney function. Last, the infusion of DCs containing higher mitochondria numbers (treated ex-vivo with healthy isolated mitochondria (10 µg/mL) one day before) also partially protected the kidneys from IRI. These studies demonstrate that pre-emptive infusion of ex-vivo reprogrammed DCs that have higher mitochondria content has therapeutic capacity to induce an anti-inflammatory regulatory phenotype to protect kidneys from injury.     

Organic-inorganic nanocomposite polymer electrolyte membranes for fuel cell applications

Organic-inorganic nanocomposite polymer electrolyte membrane (PEM) contains nano-sized inorganic building blocks in organic polymer by molecular level of hybridization. This architecture has opened the possibility to combine in a single solid both the attractive properties of a mechanically and thermally stable inorganic backbone and the specific chemical reactivity, dielectric, ductility, flexibility, and processability of the organic polymer. The state-of-the-art of polymer electrolyte membrane fuel cell technology is based on perfluoro sulfonic acid membranes, which have some key issues and shortcomings such as: water management, CO poisoning, hydrogen reformate and fuel crossover. Organic-inorganic nanocomposite PEM show excellent potential for solving these problems and have attracted a lot of attention during the last ten years. Disparate characteristics (e.g., solubility and thermal stability) of the two components, provide potential barriers towards convenient membrane preparation strategies, but recent research demonstrates relatively simple processes for developing highly efficient nanocomposite PEMs. Objectives for the development of organic-inorganic nanocomposite PEM reported in the literature include several modifications: (1) improving the self-humidification of the membrane; (2) reducing the electro-osmotic drag and fuel crossover; (3) improving the mechanical and thermal strengths without deteriorating proton conductivity; (4) enhancing the proton conductivity by introducing solid inorganic proton conductors; and (5) achieving slow drying PEMs with high water retention capability. Research carried out during the last decade on this topic can be divided into four categories: (i) doping inorganic proton conductors in PEMs; (ii) nanocomposites by sol-gel method; (iii) covalently bonded inorganic segments with organic polymer chains; and (iv) acid-base PEM nanocomposites. The purpose here is to summarize the state-of-the-art in the development of organic-inorganic nanocomposite PEMs for fuel cell applications.     

An Expedient Route to 9-Arylmethylanthracene Derivatives via Tandem Ni-Catalyzed Alkene Dicarbofunctionalization and Acid-Promoted Cyclization-Aromatization

We report a nickel-catalyzed one pot synthesis of 9-arylmethylanthracene motifs, which find applications in medicinal and material chemistry. In this synthesis, we apply three component alkene dicarbofunctionalization of 2-vinylaldimines with aryl iodides and arylzinc reagent to generate a 1,1,2-diarylethyl scaffold, which then undergoes an acid-promoted cyclization followed by aromatization to furnish 9-arylmethylanthracene cores. With the new method, a number of differently-substituted 9-arylmethylanthracene derivatives can be synthesized in good yields.     

Effects of soil and crop management practices on yields,income and nutrients losses from upland farming systems in the Middle Mountains region of Nepal

On-farm runoff plots were established during 2004 and monitored for 4 years in the Pokhare Khola watershed (Nepal) in a completely randomized design with four replications of each three treatments: traditional Farmer Practice (FP) (Zea mays–Eleusine coracana), Reduced Tillage (RT; Z. mays–Vigna ungeuculata), and Commercial Vegetable with double dose of farm yard manure (CV; Z. mays–Capsicum species) to evaluate treatment effects on soil nutrient losses, nutrient balances and crop income on Bari land (rainfed terraces). Nutrient removal due to crop harvest was found to be significantly higher than nutrient loss through soil erosion, and CV treatment exhibited a significantly higher N uptake (123 kg ha⁻¹ year⁻¹) through crop harvest than other treatments. Moreover, the CV treatment produced significantly higher income per unit area of Bari land than the other treatments. Soil organic carbon and major nutrients losses (NPK) through soil erosion were minimal [25.5 kg ha⁻¹ year⁻¹ soil organic carbon (SOC) and 5.6:0.02:0.12 kg ha⁻¹ year⁻¹ nitrogen (N), phosphorus (P), potassium (K), respectively]. Result showed that no nutrients were lost through leaching. Nutrient losses due to soil erosion and runoff were lower than previously reported in the Middle Mountain region, indicating a need to re-evaluate the soil erosion and nutrient loss problems in this region. Interventions such as reduced tillage and double dose of FYM with vegetable production were found to be effective in maintaining soil fertility and increasing farm income compared to the traditional maize-millet production system. The nutrient balance calculations suggest that integrated nutrient management techniques such as residue incorporation and application of FYM with a minimum application of chemical fertilizer are potentially sustainable production approaches for the Mid-hills of Nepal.