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101.
Swapnil Doijad S.B. Barbuddhe Sandeep Garg Sushanta Kalekar Jenney Rodrigues Dilecta D’Costa S. Bhosle Trinad Chakraborty 《Food Control》2011,22(12):1900-1904
The presence of Listeria in three milk processing environments as a potential source of milk contamination was assessed. Swab samples (n = 210) taken from milk processing plants were examined. Sample sites included the milk processing equipment, besides areas handling raw and pasteurized milk. The USDA Listeria-selective enrichment procedure was used to process the samples. Forty one (19.52%) Listeria isolates were recovered. The isolates were further subjected to biochemical and genotypic characterization. Out of 41 isolates, 16 (7.62%) were confirmed as Listeria monocytogenes, 2 (0.95%) as L. ivanovii, 19 (9.05%) as L. innocua. 1 (0.48%) as L. seeligeri and 3 (1.43%) as L. grayi. All the L. monocytogenes isolates were positive for the hlyA gene. PCR based serotyping revealed all L. monocytogenes to be of 1/2a, 1/2c, 3a and 3c serovar group. AscI and ApaI restriction analysis yielded four PFGE clusters for 16 L. monocytogenes isolates obtained from raw milk collector, milk silos, buttermilk mixer, cheese and other milk product processor. No predominant PFGE cluster was observed among these L. monocytogenes isolates. The main sources of L. monocytogenes were found to be raw milk collector and milk silos. In the present study L. monocytogenes was isolated from milk and milk products processing plants which could cross-contaminate the processed products and may possess a potential threat to public health. 相似文献
102.
Takatsuki H Tanaka H Rice KM Kolli MB Nalabotu SK Kohama K Famouri P Blough ER 《Nanotechnology》2011,22(24):245101
The potential of using actin bundles for the transport of liposomes and single cells across myosin-coated surfaces is investigated. Compared to that observed with filamentous actin, the liposome transport using actin bundles was more linear in nature and able to occur over longer distances. Bundles, but not filamentous actin, were capable of moving single cells. Cargo unloading from bundles was achieved by incubation with Triton X-100. These data suggest that actin bundling may improve the ability of the myosin motor system for nanotransport applications. 相似文献
103.
Yeonsik Jeong Sriram Lakshmanan Sandeep Kakumanu Raghupathy Sivakumar 《Wireless Networks》2011,17(3):567-582
In this paper we present a new approach called cue-based networking that uses hints or cues about the physical environment to optimize networked application behavior. We define the notion of
cues and describe how cues can be obtained using wireless sensor networks as the underlying platform. We identify both the
research and system challenges that need to be addressed to realize benefits of the approach under a target application of
video delivery over IP networks. In the process, we identify key challenges of wireless sensor networks, namely timeliness
and robustness. We design an adaptive algorithm that balances the tradeoff between them satisfying both timeliness and robustness
requirements. Through an implementation of the video delivery application using the proposed algorithm in a real home environment,
we highlight the practical benefits of the proposed approach. 相似文献
104.
Sai Madhukar Reddy Jung Jin Park Suok‐Min Na Mazin M. Maqableh Alison B. Flatau Bethanie J. H. Stadler 《Advanced functional materials》2011,21(24):4677-4683
Arrays of nanowires are fabricated with alternating segments of the magnetostrictive alloy Fe1–xGax and Cu using electrochemical deposition in nanoporous anodic aluminium oxide (AAO) templates. The difficult nature of Ga‐alloy electrochemistry is overcome by controlling mass‐transfer and hydrodynamic conditions using novel rotating disk electrode templates to obtain highly uniform segment lengths throughout the arrays. Extensive structural characterization by XRD, EBSD and TEM reveals a strong <110> textured Fe1–xGax growth. Furthermore, using vibrating sample magnetometry (VSM), we demonstrate that control of magnetization reversal processes is possible once uniform aspect ratios are obtained for both the Fe–Ga and Cu segments. 相似文献
105.
Absorption of CW Yb-fiber laser light of 1.07 μm wavelength in water has been measured at different water temperatures and laser intensities. The absorption coefficient was estimated to be 0.135 cm(-1) at 25 °C water temperature, and this was found to decrease with temperature at a rate of 5.7 × 10(-4) cm(-1) °C(-1). The absorption coefficient increased significantly when the laser beam was focused in water, and the increase depended on the distance of the focal point from the water surface. This has been attributed to the absorption and scattering losses of laser radiation in a cavity formed in water by the focused beam at laser intensities in the megawatts per square centimeter and higher range. 相似文献
106.
An experimental investigation has been conducted to study the dynamic constitutive behavior of Hastelloy X (AMS 5754) at room
and elevated temperatures under varying rates of loading. A split Hopkinson pressure bar (SHPB) apparatus was used in conjunction
with an induction coil heating system for applying dynamic loads at elevated temperatures. Experiments were carried out at
different temperatures ranging from room temperature (25 °C) to 1,100 °C at an average strain rate of 5000/s. Room temperature
experiments were carried out at varying strain rates from 1000 to 4000/s. The results show that as the strain rate increases
from quasi-static to 4000/s, the yield strength increases by approximately 50%. Also, under dynamic loading, the yield stress
decreases with temperature up to 700 °C, after which it shows a peak at 900 °C before beginning to decrease again as the temperature
is further increased. The Johnson–Cook model was used to predict the dynamic plastic response under varying rates of loading
and at different temperatures. 相似文献
107.
108.
Dichloromethane extracts of culture broth from three strains of the entomopathogenic fungusHirsutella thompsonii var.synnematosa were toxic to two species of tephritid fruit fly and inhibited conidial germination in vitro in several other entomopathogenic fungi includingBeauveria bassiana, Tolypocladium spp., andMetarhizium anisopliae. A major metabolite, toxic to apple maggot,Rhagoletis pomonella, and inhibitory to conidial germination inB. bassiana, was isolated and identified as the antibiotic (+)-phomalactone, 6-(1-propenyl)-5,-6-dihydro-5-hydroxypyran-2-one. This is the first biologically active compound of low molecular weight isolated from the genusHirsutella.Mention of a commercial or proprietary product does not constitute an endorsement by the USDA. 相似文献
109.
Tang Q Tummala N Gupta SK Schwiebert L 《IEEE transactions on bio-medical engineering》2005,52(7):1285-1294
A network of biosensors can be implanted in a human body for health monitoring, diagnostics, or as a prosthetic device. Biosensors can be organized into clusters where most of the communication takes place within the clusters, and long range transmissions to the base station are performed by the cluster leader to reduce the energy cost. In some applications, the tissues are sensitive to temperature increase and may be damaged by the heat resulting from normal operations and the recharging of sensor nodes. Our work is the first to consider rotating the cluster leadership to minimize the heating effects on human tissues. We explore the factors that lead to temperature increase, and the process for calculating the specific absorption rate (SAR) and temperature increase of implanted biosensors by using the finite-difference time-domain (FDTD) method. We improve performance by rotating the cluster leader based on the leadership history and the sensor locations. We propose a simplified scheme, temperature increase potential, to efficiently predict the temperature increase in tissues surrounding implanted sensors. Finally, a genetic algorithm is proposed to exploit the search for an optimal temperature increase sequence. 相似文献
110.
Madhukar Nilmani 《加拿大化工杂志》1982,60(5):692-694
Numerical predictions are presented for pressure change left behind by an air bubble accelerating from rest in water. The computations are made with an implicit finite difference procedure for an axisymmetric system. The magnitude of pressure predicted compares well with the results of potential theory given by previous workers1. 相似文献