Ion beam induced mixing at Co/Si interface

Ion beam mixing has emerged as a technique for understanding reactivity and chemistry at metal/Si interface and may find its applications in the field of microelectronics. We have investigated ion beam mixing at Co/Si interface induced by electronic excitation using 120 MeV Au⁺⁹ ion irradiation at different fluences, varying from 10¹² to 10¹⁴ ions/cm². Mixing was investigated by Rutherford Backscattering Spectroscopy (RBS) as a function of ion fluence and its mechanism across the interface is explained by the thermal spike model.     

Screening of native plants and algae growing on fly-ash affected areas near National Thermal Power Corporation, Tanda, Uttar Pradesh, India for accumulation of toxic heavy metals

The present investigation was carried out to screen native plants growing in fly-ash (FA) contaminated areas near National Thermal Power Corporation, Tanda, Uttar Pradesh, India with a view to using them for the eco-restoration of the area. A total number of 17 plants (9 aquatic, 6 terrestrial and 2 algal species) were collected and screened for heavy metal (Fe, Zn, Cu, Mo, B, Si, Al, Cr, Pb, Cd, Hg and As) accumulation. Differential accumulation of various heavy metals by different species of plants was observed. Hydrilla verticillata was found to be the most efficient metal accumulator among 9 aquatic plants, Eclipta alba among 6 terrestrial plants and Phormedium papyraceum between 2 algal species. In general, the maximum levels of most metals were found in terrestrial plants while the lowest in algal species. However, translocation of the metals from root to shoot was found to be higher in aquatic plants than terrestrial ones. These results suggest that various aquatic, terrestrial and algal species of plants may be used in a synergistic way to remediate and restore the FA contaminated areas.     

Controlled manipulation of carbon nanopillars and cantilevers by focused ion beam

We explore a novel phenomenon of focused ion beam (FIB) induced bending of carbon nanopillars or cantilever structures. The bending occurs towards the ion beam during scanning. The explanation of this bending has been sought on the basis of a model which considers temperature rise and gradients caused by the impinging ion beam. The process is controllable and reversible, which makes it highly suitable for in?situ manipulation to make desired 3D shapes by the piecewise bending of the nanopillars and cantilever structures during their fabrication using electron beam or FIB chemical vapor deposition (EB-CVD or FIB-CVD). Its usefulness in the fabrication of nanosize mechanical components has been demonstrated by making a branch structure from a single cantilever.     

Effect of Co loading on the hydrogen storage characteristics of hollow glass microspheres (HGMs)

The use of hydrogen as a fuel either direct combustion in an IC engine or for power generation in fuel cells continues to be a topic of significant interest. Developing and popularizing fuel cells for vehicular or other stationary applications depends upon the availability of safe and reliable hydrogen storage method. The greatest challenge as of now in this regard is the production of a light weight, nontoxic and easily transportable material which can store hydrogen. World-wide research is being conducted on developing newer materials for hydrogen storage. Hollow glass microspheres (HGMs) can be considered to be a potential hydrogen carrier which can store and deliver hydrogen for energy release applications. In this paper, we are reporting the preparation and characterization of cobalt loaded HGMs from amber glass powder for hydrogen storage applications. The feed glass powder with different percentage of cobalt loading was prepared by soaking and drying the feed glass powder in required amount of cobalt nitrate hexahydrate solution. Further, the dried feed glass powder was flame spheroidised to get cobalt loaded HGMs. Characterizations of all the HGMs samples were done using SEM, FTIR and XRD techniques. Hydrogen adsorptions on all the samples were done for 10 bar pressure at room temperature and 200 °C for 5 h. The results showed that the hydrogen adsorption capacity on these samples increased with increase in cobalt wt% from 0.2 to 2.0%. The hydrogen storage capacity of HACo2 was found to 2.32 wt% for 10 bar pressure at 200 °C.     

Nutritional value of animal feed grade wheat as replacement for maize in lamb feeding for mutton production

The utilization of abundantly available animal feed grade wheat (AFW) as a replacement for conventional and costly cereal supplement in lamb feeding to lower the cost of mutton production was explored. Thirty‐five growing lambs divided into five equal groups and were fed diets containing 0, 118, 235, 353 or 470 g kg^?1 AFW replacing equal quantity of maize. The diets were fed in the form of composite feed mixture, which had a roughage (Prosopis cineraria leaves) to concentrate ratio of 25:75. Dry matter intake (DMI) was not different in these groups, ranging from 35 to 42 g kg^?1 body weight, while AFW inclusion linearly (P < 0.05) reduced DMI. The digestibility coefficients of dry matter (DM), organic matter (OM), crude protein (CP) and cellulose were not affected by AFW addition, whereas neutral detergent fibre and acid detergent fibre digestibility coefficients were reduced (P < 0.05). The digestible CP content (142.7–162.7 g kg^?1 diet) increased (P < 0.01) linearly with increased AFW inclusion levels. However, AFW additions did not affect metabolizable energy (ME) value of diet (10.2–10.5 MJ kg^?1 diet DM). Digestible CP intake was similar but digestible DM and OM intake tended to decrease (P < 0.05) linearly when expressed in terms of g kg^?1 W^0.75. ME intake (MJ d^?1) was not different among the diets but showed linear (P = 0.041) reducing trends with increasing AFW levels in diet. The efficiency of ME and N utilization for unit gain was also not affected by AFW incorporation. N retained as g d^?1, percentage of intake and percentage of absorbed ranged from 15.4 to 19.5 g, 49.7% to 60.3% and 62.6% to 74.6%, respectively. Intake and utilization of dietary N was not affected but urinary N excretion reduced (P < 0.05) linearly by AFW. Daily microbial N (MN) flow estimated by urinary purine derivative excretion was significantly (P < 0.01) higher for lambs fed a diet with AFW 235 g kg^?1 (3.05 g MN) and 353 g kg^?1 (2.51 g MN) compared to without AFW diet (1.31 g MN). MN when expressed as g kg^?1digestible organic matter intake (DOMI) and microbial protein g kg^?1 digestible organic matter apparently fermented in rumen (DOMR) followed a similar trend. During the growth trial, lambs fed diets containing AFW (353 g kg^?1), which replaced 75% maize had higher total gain (14 kg, P < 0.05) and average daily gain (ADG 154 g, P < 0.05). However, feed efficiency (feed consumed kg^?1 live weight gain) was not different. Rumen pH and microbial enzyme activities studied 4 h post feeding revealed that AFW did not affect rumen pH, which ranged from 5.95 to 6.30. Similarly, carboxymethyl cellulase and β‐xylosidase enzyme activities were not different among treatments, but AFW inclusion linearly (P = 003) increased carboxymethyl cellulase enzyme activities. The α‐amylase enzyme activity differed significantly (P < 0.05) and was highest (22.6 IU) in groups where AFW replaced maize completely. It was concluded that, in lambs reared under intensive system for mutton production on high concentrate diets, conventional and costly energy supplements like maize can be replaced up to 75% with a low‐cost animal feed grade wheat to economize on cost of production. However, more studies are required to confirm these inclusion levels for greater economic returns. Copyright © 2007 Society of Chemical Industry     

In vitro and in vivo modulation of testosterone mediated alterations in apoptosis related proteins by [6]-gingerol

Ginger (Zingiber officinale, Zingiberaceae) has been widely used as a dietary spice, and as a traditional oriental medicine. The rhizome of ginger contains pungent vanillyl ketones, including [6]-gingerol and [6]-paradol, and have been credited with therapeutic and preventive health benefits, including anti-cancer activity. Prostate cancer is an attractive target for chemoprevention because of its ubiquity, treatment-related morbidity, long latency between premalignant lesions and clinically evident cancer, and defined molecular pathogenesis. Here we are reporting the modulatory effects of [6]-gingerol on testosterone-induced alterations on apoptosis related proteins in both in vitro, androgen sensitive LNCaP cells and in vivo, ventral prostate of Swiss albino mice. [6]-gingerol treatment resulted apoptosis in LNCaP cells, as indicated by depolarization of mitochondrial membrane potential, increase in sub G1 cell population by flow cytometry and the appearance of DNA laddering pattern in agarose gel electrophoresis. Results of western blot analysis showed that [6]-gingerol upregulated the testosterone depleted levels of p53 in mouse prostate and upregulated its downstream regulator Bax and further activated Caspase-9 and Caspase-3 in both LNCaP cells and in mouse prostate. We also found downregulation of testosterone induced antiapoptotic proteins, Bcl-2 and Survivin expression by [6]-gingerol in both LNCaP cells and in mouse ventral prostate. Thus, [6]-gingerol shows its protective effects in both in vivo and in vitro prostate cancer models by modulation of proteins involved in apoptosis pathway.     

Network condition and application‐based data adaptive intelligent message routing in vehicular network

Recent advances in intelligent transportation systems enable a broad range of potential applications that significantly improve the vehicle and road safety and facilitate the efficient dissemination of information among the vehicles. To assist the vehicle traffic, message broadcasting is a widely adopted technique for road safety. But efficient message broadcasting is a significant issue, especially in a high network density due to the broadcast storm problem. To solve this issue, several methods are proposed to eliminate the redundant transmission of safety packets. However, they lack in restricting the broadcasting region of safety messages, and the transmissions of safety packets outside the dangerous region, and force the vehicles to unnecessary detours. This paper proposes an adaptive multimode routing protocol, network condition, and application‐based data adaptive intelligent message routing in vehicular network (NetCLEVER) that supports 2 modes of operation such as message broadcasting and intelligent routing. In message broadcasting mode, the NetCLEVER decides the dangerous region of the network by considering the changes of neighbor vehicles velocity, instead of current vehicle velocity, because a vehicle decision in velocity is interdependent with the preceding vehicles. In intelligent routing mode, the NetCLEVER exploits the cuckoo search optimization in routing by taking into account multiple routing factors such as the road topology of intersections and traffic signals and their impact on link stability, which improves the reliability of routing packets significantly. The performance evaluation illustrates that the proposed NetCLEVER improves reliable wireless communication as well as road safety in vehicular ad hoc networks.     

Diverse Functions of Tim50, a Component of the Mitochondrial Inner Membrane Protein Translocase

Mitochondria are essential in eukaryotes. Besides producing 80% of total cellular ATP, mitochondria are involved in various cellular functions such as apoptosis, inflammation, innate immunity, stress tolerance, and Ca²⁺ homeostasis. Mitochondria are also the site for many critical metabolic pathways and are integrated into the signaling network to maintain cellular homeostasis under stress. Mitochondria require hundreds of proteins to perform all these functions. Since the mitochondrial genome only encodes a handful of proteins, most mitochondrial proteins are imported from the cytosol via receptor/translocase complexes on the mitochondrial outer and inner membranes known as TOMs and TIMs. Many of the subunits of these protein complexes are essential for cell survival in model yeast and other unicellular eukaryotes. Defects in the mitochondrial import machineries are also associated with various metabolic, developmental, and neurodegenerative disorders in multicellular organisms. In addition to their canonical functions, these protein translocases also help maintain mitochondrial structure and dynamics, lipid metabolism, and stress response. This review focuses on the role of Tim50, the receptor component of one of the TIM complexes, in different cellular functions, with an emphasis on the Tim50 homologue in parasitic protozoan Trypanosoma brucei.     

Transport behavior of selected nanoparticles with different surface coatings in granular porous media coated with Pseudomonas aeruginosa biofilm

Well-controlled laboratory column experiments were conducted to understand the influence of Pseudomonas aeruginosa (P. aeruginosa) biofilms on the transport of selected engineered nanoparticles (ENPs) in granular porous media representative of groundwater aquifers or riverbank filtration settings. To understand the importance of particle size on retention in the biofilm-coated granular (quartz sand) matrix, column experiments were carried out using nanosized (20 nm) and micrometer-sized (1 μm) sulfate-functionalized polystyrene latex particles (designated as 20 nSL and 1 mSL, respectively). Additional experiments conducted with nanosized (20 nm) carboxyl-modified latex particles (20nCL) and carboxyl-modified CdSe/ZnS quantum dots (QDs) provide information on the influence of particle surface chemistry on retention. Biofilm grown on the surface of the sand was characterized by total biomass quantification, confocal laser scanning microscopy (CLSM), and electrokinetic analysis. All four particles exhibit increased retention in the biofilm-coated packed bed: e.g., the attachment efficiency (α) of the 1 mSL particle increases from 0.40 to 1.7, whereas α for the 20 nSL particle increases from 0.04 to 0.10 in the biofilm-coated system. Particle surface chemistry can also influence the affinity of the ENPs for the biofilm coating as revealed by the greater attachment of the 20 nSL particle onto the biofilm-coated sand (α = 0.10) than its carboxylated counterpart (α = 0.04). Column experiments conducted using sand coated with growth medium (LB) or extracellular polymeric substances (EPS) extracted from P. aeruginosa biofilms further reveal that particle surface chemistry influences the interaction between the different ENPs and these coated sand surfaces. Namely, coating of sand surfaces with LB medium or bacterial EPS does not affect the transport of the sulfonated nanoparticle, but the LB coating leads to decreased retention of the carboxylated latex nanoparticle. Furthermore, our results show that EPS coatings are not necessarily good surrogates for biofilm-coated sand. Electrokinetic characterization of the clean and coated sand surfaces also reveals that the extent of particle retention is not controlled by electrical double layer interactions. Future studies should thus be aimed at improving our understanding of the fundamental mechanisms (both colloidal and noncolloidal) governing nanoparticle transport and fate in biofilm-laden granular aquatic environments.