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161.
In this study we present an analysis of the research trends in Pakistan in the field of biotechnology for the period 1980–2011. Starting with just 15 publications in 1980 with a negligible annual growth rate for the initial 15 years, the number of publications reached 3,273 in 2011 with an annual growth rate of 22 % for the last 15 years. This growth in publications is studied through factors such as Relative Growth Rate and Doubling Time. A comparison of organizations actively engaged in research in biotechnology is made through factors such as their total publications, total citations, and average citations per paper and indices that determine the quality of publications like h-index, g-index, hg-index and p-index. University of Karachi shows the highest number of publications (2,698), while National Institute of Biotechnology and Genetic Engineering with fewer publications shows the highest average citation per paper (8.07). Agha Khan University however, shows the highest h, g, hg and p indices.  相似文献   
162.
Radiation-induced free radicals were investigated in the shells and membranes of ostrich, duck, hen, and quail eggs using electron spin resonance (ESR) spectroscopy. The non-irradiated egg shells and membranes showed a single resonance signal centered at g?=?2.0048?±?0.0001 and 2.0072?±?0.0002, respectively. Upon irradiation (1–3 kGy), a dose-dependent asymmetric ESR signal centered at g?=?1.9998?±?0.0002 was also determined in all eggshell samples, whereas the membranes were found silent for radiation-specific ESR signals. An X-ray diffraction spectrometric study showed the abundance of calcite minerals in the all egg shells. Radiation-induced and trapped CO 3 3? , CO 3 ? , and CO 2 ? paramagnetic entities in the calcite matrix of egg shells might be responsible for a typical ESR signal. The ESR-based identification of all irradiated eggshells was easily possible in practical dose range (1–3 kGy).  相似文献   
163.
We measure the elastic modulus of a single horizontal ZnO nanorod [NR] grown by a low-temperature hydrothermal chemical process on silicon substrates by performing room-temperature, direct load-controlled nanoindentation measurements. The configuration of the experiment for the single ZnO NR was achieved using a focused ion beam/scanning electron microscope dual-beam instrument. The single ZnO NR was positioned horizontally over a hole on a silicon wafer using a nanomanipulator, and both ends were bonded with platinum, defining a three-point bending configuration. The elastic modulus of the ZnO NR, extracted from the unloading curve using the well-known Oliver-Pharr method, resulted in a value of approximately 800 GPa. Also, we discuss the NR creep mechanism observed under indentation. The mechanical behavior reported in this paper will be a useful reference for the design and applications of future nanodevices.  相似文献   
164.
Functional magnetic resonance imaging (fMRI) data is processed by different techniques for detection of activated voxels including principal component analysis (PCA), independent component analysis (ICA), non‐negative matrix factorization (NMF), and so on. In this work, a modified version of NMF method is proposed in which data is not supposed to be non‐negative. The proposed scheme is applied to synthetic fMRI data along with NMF conventional method. The results of the proposed scheme show that it is not only computationally efficient but also has good quality results as compared to that of NMF in terms of average correlation. Finally, proposed method is applied to monkey's fMRI data, and the results are compared with that of NMF and ICA. © 2012 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 22, 195–199, 2012  相似文献   
165.
This paper presents a statistical technique to optimise process conditions for multiple quality criteria in micro-injection moulding. A sample hierarchical component with micro-features was replicated where it was required to improve the process conditions for both complete mould filling and variability in mass. A design-of-experiments approach was used to investigate the effect of five processing parameters on both criteria. It was found that holding pressure, melt temperature and injection velocity were statistically significant for part mass, whereas injection velocity alone was significant for mass variation. Desirability functions were used to predict processing conditions that improved both requirements within pre-set conditions. The technique was validated by experiment and it was shown to be applicable for process parameters for multiple criteria.  相似文献   
166.
The effect of guar gum, a non-gelling neutral polysaccharide, on the thermal gelation of soybean β-conglycinin was analysed using the dynamic oscillatory rheological measurement, differential scanning calorimetry and texture profile analysis. The endothermic peak temperature of β-conglycinin in the presence of 0.5% guar gum was about 89.1 °C. However, the endothermic peaks shifted to higher temperatures as the guar gum concentration increased from 0.05% to 0.5%, which could be attributed to the thermodynamic incompatibility with guar gum, resulting in a promoted aggregation of the thermally denatured β-conglycinin. Furthermore, the elastic modulus increased with increasing concentration of guar gum, with a less frequency dependence. In addition, the springiness, cohesiveness and fracturability enhanced but the hardness decreased, as the guar gum concentration increased. The study demonstrated that incorporation of guar gum improved markedly the thermal and functional properties of soybean β-conglycinin thermal-induced gel, which can help better to design new food formulations.  相似文献   
167.
Herein an improved protocol for the synthesis of imidazo[4,5‐b]pyridines and imidazo[4,5‐b]pyrazines using a palladium‐catalyzed amidation that utilizes Xantphos as an ancillary phosphine ligand is reported. The use of a binary solvent system comprised of 1,4‐dioxane and tert‐amyl alcohol was crucial in eliminating unwanted by‐products.

  相似文献   

168.
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.  相似文献   
169.
We studied the effects of different processing treatments, including soaking, steeping, boiling in water and germination and chemical treatments with H2SO4, HCl, lime and NaHCO3, on the removal of a neurotoxin, β‐N‐oxalyl‐L ‐α,β‐diaminopropionic acid (β‐ODAP), from Indian vetch (Iv) and addition of detoxified Iv in chapatti. The toxin level was quantified by using thin‐layer chromatographic and spectrophotometric methods. Maximum removal was observed after steeping in water at 60–70°C for 8 h with seven rinses. The samples were dried, milled into flour and added to chapatti at different levels. Sensory attributes revealed that the chapattis were most acceptable by judges when supplemented with up to 200 g kg−1 of flour. The protein level of Iv flour increased from 124 to 174 g kg−1 as result of supplementation at 300 g kg−1. Biological studies with albino rats showed that detoxified Iv had a better impact on nutritional status. Copyright © 2006 Society of Chemical Industry  相似文献   
170.
Power consumption analyzes of embedded processors indicate that a significant amount of power is consumed in accessing memory and in the control path. Based on this, and on the runtime characteristics of signal processing applications, we advocate the use of instruction buffering as a power-saving technique for processors for signal processing and multimedia applications. Two approaches, a decoded instruction buffer (DIB) and a decoded instruction cache, are considered. Performance improvements in representative applications in speech processing such as, the vector sum excited linear prediction (VSELP), linear prediction coding coefficient computation (LPC), and two-dimensional 2-D 8×8 DCT which is used in image compression, are provided. The reduction in power obtained is between between 25 and 30%  相似文献   
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