A comparative study of full‐duplex relaying schemes for low latency applications

Various sectors are likely to carry a set of emerging applications while targeting a reliable communication with low latency transmission. To address this issue, upon a spectrally‐efficient transmission, this paper investigates the performance of a 1 full‐dulpex relay system and considers for that purpose, 2 basic relaying schemes, namely, the symbol‐by‐symbol transmission, i.e., amplify‐and‐forward and the block‐by‐block transmission, i.e., selective decode‐and‐forward. The conducted analysis presents an exhaustive comparison, covering both schemes, over 2 different transmission modes, i.e., the noncombining mode where the best link, direct, or relay link is decoded and the signals combining mode, where direct and relay links are combined at the receiver side. While targeting latency purpose as a necessity, simulations show a refined results of performed comparisons and reveal that amplify‐and‐forward relaying scheme is more adapted to combining mode, whereas the selective decode‐and‐forward relaying scheme is more suitable for noncombining mode.     

Measurement of natural radioactivity and dose rate assessment of terrestrial gamma radiation in the soil of southern Punjab, Pakistan

Activity concentrations of (226)Ra, (232)Th, (40)K and (137)Cs in soil samples collected from the most populous area of southern Punjab of Pakistan have been measured by gamma-ray spectrometry. The measured activity concentrations for these radionuclides are compared with the reported data from different other countries and it is found that measured activity concentrations are comparable with the worldwide measured average values reported by the UNSCEAR. Subsequently assessed radiological effects show that the mean radium equivalent activity (Ra(eq)) is 96.7 +/- 15.2 Bq kg(-1) and air absorbed dose rate (D) is 46.1 +/- 7.3 nGy h(-1). The values of internal and external radiation hazard indices are found to be less than unity. The annual effective radiation dose is calculated to be 0.28 +/- 0.05 mSv, which is well below the limit of 1.0 mSv y(-1) recommended by the International Commission on Radiological Protection, for the general public.     

Physical and chemical modification of distillery sludge for Pb(II) biosorption

The waste distillery sludge from sugar-cane industry was pretreated physically (boiled, heated and autoclaved) as well as chemically (HCl, H(2)SO(4), H(3)PO(4), NaOH, Ca(OH)(2), Al(OH)(3), C(6)H(6), HCHO, CH(3)OH and C1(2)H(25)OSO(3)Na (sodium dodecyl sulphate (SDS)) for assessing the comparative sorption capacity of untreated and modified distillery sludge for Pb(II) biosorption from aqueous solutions. Experiments were conducted in shake flasks on a batch basis to access the effect of different experimental parameters such as pH, biosorbent dosage, biosorbent size, initial Pb(II) concentration and contact time. The uptake capacity 'q' (mg/g) of untreated and pretreated distillery sludge was in following order: NaOH (51.29+/-1.21)>HCl (49.82+/-1.22)>HCHO (49.56+/-1.14)>H(2)SO(4) (47.71+/-1.20)>HgCl(2) (45.32+/-1.06)>Ca(OH)(2) (44.01+/-1.18)>MeOH (43.73+/-1.23)>C(6)H(6) (42.72+/-1.19)>H(3)PO(4) (42.01+/-1.17)>SDS (40.87+/-1.27)>autoclaved (40.23+/-1.24)>Boiled (39.95+/-1.19)>heated (38.87+/-1.32)>Al (OH)(3) (38.30+/-1.14)>untreated (37.76+/-1.21). In further parameter studies, the optimized biosorbent size was 0.250 mm at pH 5 and best dose was 0.05 g of biosorbent. The applicability of the Langmuir and Freundlich models for sorption process was tested and best fitted model was Langmuir with the coefficient of determination (R(2)) value, 0.97, the process followed second order kinetic mechanism.     

Synthesis, conformation and biological evaluation of the enantiomers of 3-fluoro-gamma-aminobutyric acid ((R)- and (S)-3F-GABA): an analogue of the neurotransmitter GABA

Gamma-aminobutyric acid or GABA (1) is one of the major inhibitory amino acid neurotransmitters of the central nervous system. This article describes the first synthesis of both the (R)- and (S)- enantiomers of 3-fluoro-GABA (2, 3F-GABA). DFT calculations were carried out in a continuum solvent model (PCM-B3LYP) to estimate the preferred conformations of 3F-GABA in aqueous solution. NMR coupling constants were calculated for each conformer and were then used to simulate the NMR spectra to evaluate the solution conformation of 3F-GABA. A preliminary evaluation of the 3F-GABA enantiomers shows that they act similarly as agonists of cloned GABA(A) receptors; however, they behave quite differently in a whole animal (Xenopus laevis tadpole model).     

Study of the Role of the Tyrosine Kinase Receptor MerTK in the Development of Kidney Ischemia-Reperfusion Injury in RCS Rats

Renal ischaemia reperfusion (I/R) triggers a cascade of events including oxidative stress, apoptotic body and microparticle (MP) formation as well as an acute inflammatory process that may contribute to organ failure. Macrophages are recruited to phagocytose cell debris and MPs. The tyrosine kinase receptor MerTK is a major player in the phagocytosis process. Experimental models of renal I/R events are of major importance for identifying I/R key players and for elaborating novel therapeutical approaches. A major aim of our study was to investigate possible involvement of MerTK in renal I/R. We performed our study on both natural mutant rats for MerTK (referred to as RCS) and on wild type rats referred to as WT. I/R was established by of bilateral clamping of the renal pedicles for 30′ followed by three days of reperfusion. Plasma samples were analysed for creatinine, aspartate aminotransferase (ASAT), lactate dehydrogenase (LDH), kidney injury molecule -1 (KIM-1), and neutrophil gelatinase-associated lipocalin (NGAL) levels and for MPs. Kidney tissue damage and CD68-positive cell requirement were analysed by histochemistry. monocyte chemoattractant protein-1 (MCP-1), myeloperoxidase (MPO), inducible nitric oxide synthase (iNOS), and histone 3A (H3A) levels in kidney tissue lysates were analysed by western blotting. The phagocytic activity of blood-isolated monocytes collected from RCS or WT towards annexin-V positive bodies derived from cultured renal cell was assessed by fluorescence-activated single cell sorting (FACS) and confocal microscopy analyses. The renal I/R model for RCS rat described for the first time here paves the way for further investigations of MerTK-dependent events in renal tissue injury and repair mechanisms.     

On the adoption of electricity as a domestic source by Mozambican households

In Mozambique, domestic energy is often composed of a mix of sources, primarily used for lighting and cooking, with biomass and kerosene as more common sources. Electrification programs, intended to connect new consumers countrywide, have not significantly contributed either to the intensification of electricity consumption or to the reduction of the use of biomass in households. The choice of energy source is dependent on price and on the capability of the household to invest in energy-consuming appliances. Based on the data from a household survey carried out in Mozambique during 2002/03, this paper analyzes the geographic differences in unit expenditures for domestic energy and finds evidence of an inverted energy ladder with prices of useful energy units. The data show that biomass sources are often more expensive per unit of useful energy than higher-grade sources, supporting arguments favoring electrification as a poverty alleviation strategy. In addition, this study estimates the likelihood of poor households transitioning from biomass to electricity consumption based on various factors. Results indicate that income is not a determining factor in the transition, but wealth and the level of the Primary Energy Consumption Share (PECS) are as important factors as the nature of the energy mix.     

Do African American mothers really “love” their sons and “raise” their daughters?

This study assessed 1500 adolescents from the National Longitudinal Study of Youth to test the hypothesis that African American mothers differentially socialize their girls and boys. The results showed that later-born boys had fewer chores, argued more with their mothers, lived in less cognitively stimulating homes, and were not allowed to make the same decisions as were the girls or firstborn boys at the same age. The later-born boys were also lowest in achievement and highest in externalizing behaviors. Parenting differences accounted for the achievement differences but not for the externalizing behavior differences. It was concluded that the later-born boys would achieve at the same rates as their siblings if they were socialized in the same manner as their siblings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)