Assessment of sperm count in rural population of central India

26 clinician trainees' recollections of experiences in a diagnostic preschool program were analyzed in terms of strength and weaknesses of the program.     

High resistivity In-doped ZnTe: electrical and optical properties

Semi-insulating <111> ZnTe prepared by In doping during Bridgman growth was found to have a resistivity of 5.74 × 10⁷ ohm-cm, the highest reported so far in ZnTe, with hole concentration of 2.4 × 10⁹/cm³ and hole mobility of 46 cm² /V.s at 300 K. The optical band gap was 2.06 eV at 293 K compared with 2.26 eV for undoped semiconducting ZnTe. Thermally stimulated current (TSC) studies revealed 2 trap levels at depths of 202–222 meV and 412–419 meV, respectively. Photoluminescence (PL) studies at 10 K showed strong peaks at 1.37 eV and 1.03 eV with a weak shoulder at 1.43 eV. Short anneal for 3 min at 250°C led to conversion to a p-type material with resistivity, 14.5 ohm-cm, indicating metastable behaviour. Raman studies carried out on undoped and In-doped samples showed small but significant differences. Possible models for semi-insulating behaviour and meta-stability are proposed.     

Analysis of Fatty Acid and Lignan Composition of Indian Germplasm of Sesame to Evaluate Their Nutritional Merits

An attempt was made to individually analyze a germplasm collection of 54 indigenous Indian sesame cultivars for fatty acid and lignan composition of their seed oil by gas chromatography and high performance liquid chromatography, respectively. The entries varied in their fatty acid and lignan composition. The mean percentage contents of palmitic, stearic, oleic, linoleic and α‐linolenic acids ranged between 10–22, 5–10, 38–50, 18–43 and less than 1 whereas sesamol, sesamin and sesamolin scored between 3–37, 27–67, 20–59 of the total percentage of lignan, respectively. The highest percentage of α‐linolenic acid (ALA) was obtained in Var‐9 (1.3 % of the total fatty acids). Among the lignans, high sesamin content is considered to be significant, particularly in terms of long shelf life and nutraceutical value of sesame seed oil. The study has broadened our understanding related to differential biochemical composition of the rich sesame germplasms, thereby providing us with a useful groundwork for identifying potential targets and suitable cultivars for genetic engineering approaches to be undertaken in order to improve the nutritional quality of sesame oil, which in turn would be beneficial towards human health.     

Biodegradation kinetic modeling of acrylic acid-grafted polypropylene during thermophilic phase of composting

Iranian Polymer Journal - This work aims at modelling and characterizing the kinetics of biodegradation of acrylic acid-grafted polypropylene. Different films of acrylic acid-grafted polypropylene...     

Self-Assembly and Neurotoxicity of β-Amyloid (21–40) Peptide Fragment: The Regulatory Role of GxxxG Motifs

The three GxxxG repeating motifs from the C-terminal region of β-amyloid (Aβ) peptide play a significant role in regulating the aggregation kinetics of the peptide. Mutation of these glycine residues to leucine greatly accelerates the fibrillation process but generates a varied toxicity profile. Using an array of biophysical techniques, we demonstrated the uniqueness of the composite glycine residues in these structural repeats. We used solvent relaxation NMR spectroscopy to investigate the role played by the surrounding water molecules in determining the corresponding aggregation pathway. Notably, the conformational changes induced by Gly³³ and Gly³⁷ mutations result in significantly decreased toxicity in a neuronal cell line. Our results indicate that G³³xxxG³⁷ is the primary motif responsible for Aβ neurotoxicity, hence providing a direct structure–function correlation. Targeting this motif, therefore, can be a promising strategy to prevent neuronal cell death associated with Alzheimer's and other related diseases, such as type II diabetes and Parkinson's.     

Genetic homogeneity among Listeria monocytogenes strains from infected patients and meat products from two geographic locations determined by phenotyping,ribotyping and PCR analysis of virulence genes

Thirty Listeria monocytogenes isolates from human patients and foods originated from two different geographic locations without any epidemiological relations were analyzed for their genotypic and phenotypic virulence gene expressions and genetic relatedness. All strains contained virulence genes, inlA, inlB, actA, hlyA, plcA and plcB, with expected product size in PCR assay except for the actA gene. Some strains produced actA gene product of 268 and others 385 bp. Phenotypically, all were hemolytic but showed variable expressions of phospholipase activity. Ribotyping classified isolates into 12 different groups based on the similarity to DuPont Identification numbers (DID), which consisted primarily of clinical or food isolates or both. Cluster analysis also indicated possible existence of clones of L. monocytogenes that are found in food or human hosts or are evenly distributed between these two. Two isolates (F1 from food and CHL1250 from patient) had unique ribotype patterns that were not previously reported in the RiboPrinter database. This study indicates distribution of diverse L. monocytogenes strains in clinical and food environments. The isolates showed 92-99% genetic homogeneity, in spite of their origins from two different geographic locations and environments.     

Novel Low-Overhead Operand Isolation Techniques for Low-Power Datapath Synthesis

Power consumption in datapath modules due to redundant switching is an important design concern for high-performance applications. Operand isolation schemes that reduce this redundant switching incur considerable overhead in terms of delay, power, and area. This paper presents novel operand isolation techniques based on supply gating that reduce overheads associated with isolating circuitry. The proposed schemes also target leakage minimization and additional operand isolation at the internal logic of datapath to further reduce power consumption. We integrate the proposed techniques and power/delay models to develop a synthesis flow for low-power datapath synthesis. Simulation results show that the proposed operand isolation techniques achieve at least 40% reduction in power consumption compared to original circuit with minimal area overhead (5%) and delay penalty (0.15%)     

Instability of plane compressible gas sheets

Summary The instability of a plane compressible gas sheet in a quiescent viscous liquid medium of infinite expanse has been studied. It is found that there exist two unstable modes of disturbances, sinuous and varicose. For temporal instability, sinuous disturbance is stable if the gas Weber number, defined as the ratio of aerodynamic to capillary forces, is less than unity, varicose mode controls the instability process except for large Weber numbers when both modes become equally important, and gas compressibility effect always enhances instability development and induces an additional range of unstable wave numbers. For spatial-temporal evolution of disturbances, it is found that convective instability does not exist at all and the instability of plane gas sheets is always absolute in nature, which is strikingly opposite to the instability of plane liquid sheets. The absolutely unstable disturbance is found always temporally growing, although it may be spatially growing or decaying depending on flow conditions. Gas compressibility always enhances and liquid viscosity damps out both the temporal and the spatial part of absolute instability growth rate. Although the Weber number always promotes the temporal growth rate of absolute instability, it has a dual effect of enhancing and inhibiting the spatial growth rate.     

Device-Aware Yield-Centric Dual-Vt Design Under Parameter Variations in Nanoscale Technologies

Dual-V_t design technique has proven to be extremely effective in reducing subthreshold leakage in both active and standby mode of operation of a circuit in submicrometer technologies. However, aggressive scaling of technology results in different leakage components (subthreshold, gate and junction tunneling) to become significant portion of total power dissipation in CMOS circuits. High-V_t devices are expected to have high junction tunneling current (due to stronger halo doping) compared to low-V_t devices, which in the worst case can increase the total leakage in dual-V_t design. Moreover, process parameter variations (and in turn V_t variations) are expected to be significantly high in sub-50-nm technology regime, which can severely affect the yield. In this paper, we propose a device aware simultaneous sizing and dual-V_t design methodology that considers each component of leakage and the impact of process variation (on both delay and leakage power) to minimize the total leakage while ensuring a target yield. Our results show that conventional dual-V_t design can overestimate leakage savings by 36% while incurring 17% average yield loss in 50-nm predictive technology. The proposed scheme results in 10%-20% extra leakage power savings compared to conventional dual-V_t design, while ensuring target yield. This paper also shows that nonscalability of the present way of realizing high-V_t devices results in negligible power savings beyond 25-nm technology. Hence, different dual-V_t process options, such as metal gate work function engineering, are required to realize high-performance and low-leakage dual-V_t designs in future technologies.