Robust Adaptive Intra Refresh for Multiview Video

Transmission error propagation in wireless multimedia communication systems has become a recurring problem. This persistent problem has led to grave consequences on the visual quality of the decoded video. It is against this backdrop that, we present an adaptive intra refresh (AIR) error-resilient coding tool to mitigate the effect of transmission error propagation in 3D video communications. This work utilizes periodic insertion of intra macroblocks in badly error-infected frames temporally as well as related frames in the multi view video scheme. Our objective is to maximize the transmission efficiency while ensuring the transmission robustness of the coded bitstream. The selection of periodic macroblocks is based on areas with high motion above a pre-set threshold. The coding modes of the macroblocks are based on the distortion expectation due to transmission errors. Extensive simulation results show significant improvement in both objective and subjective video quality at different intra refresh rates

Low Cost Constant – Head Drip Irrigation Emitter for Climate Change Adaptation in Nigeria: Engineering Design and Calibration

A low cost constant – head emitter for drip irrigation was developed using cheap and readily available materials as a substitute for the imported drip emitters which deter the adoption of drip irrigation in sub – Saharan Africa (SSA). The emitter was calibrated at both laboratory scale and on the field. The drip system comprises of abarrel, sub-main line, lateral lines, tubes and emitters, it can irrigate140 crop stands and can be extended to 560 stands. The emitters produced a mean discharge and emission uniformity (Eu) of 1.60l/hr. and 74 % respectively; while the calibrated manufacturer’s coefficient of variation and distribution uniformity of discharge were 0.098 and 86.3% respectively. The system operates under low pressure (87.9 mbar) and can deliver the daily crop water requirement of a crop like maize in 20 minutes; the overall system performance based on field calibration is generally satisfactory and show potential for improvement when compared with global standards for drip systems. The system’s low cost of N15, 870 ($79) gives it an edge over existing locally developed drip systems, the low technology and the use of locally available materials coupled with the water savings will enable famers to adapt to the impact of climate change in sub-Saharan Africa through the production of high value crops in the dry season.http://dx.doi.org/10.4314/njt.v34i4.3

Reduction of liver stiffness following resolution of acute flares of chronic hepatitis B

Background: Measuring liver stiffness is becoming more popular as a non-invasive tool for assessing liver fibrosis. Aim: To assess the effect of severe hepatitis B flare on liver stiffness and determine factors that correlate with liver stiffness measurements. Methods: Twenty-nine patients with severe hepatitis B flare (ALT > 10 × upper limit of normal) were followed up for 1 year. Serial transient elastography was performed at the time of flare, 3-6, and 12 months after flare. Results: At the time of flare, the median liver stiffness was 16.8 kPa, with no patients having normal liver stiffness (<6 kPa). There was a significant decrease in liver stiffness from baseline to 3-6 months (16.8 vs. 7.9 kPa, respectively, P < 0.001), and a further smaller decline from 3-6 to 12 months (7.9 vs. 6.9 kPa, respectively, P = 0.039). By 12 months, 10 (34%) had normalized their liver stiffness. Baseline parameters which correlated with liver stiffness include bilirubin, ALT, albumin, prothrombin time and platelet levels (all P < 0.05). Conclusion: Liver stiffness was increased in patients with severe hepatitis B flares, with return to near normal levels by 6 months. Transient elastography for proper assessment of liver fibrosis should be performed at least 6 months after flare. © 2010 The Author(s).published_or_final_versionSpringer Open Choice, 31 May 201

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum