The Friedreich ataxia GAA repeat expansion mutation induces comparable epigenetic changes in human and transgenic mouse brain and heart tissues

Friedreich ataxia (FRDA) is caused by a homozygous GAA repeat expansion mutation within intron 1 of the FXN gene, leading to reduced expression of frataxin protein. Evidence suggests that the mutation may induce epigenetic changes and heterochromatin formation, thereby impeding gene transcription. In particular, studies using FRDA patient blood and lymphoblastoid cell lines have detected increased DNA methylation of specific CpG sites upstream of the GAA repeat and histone modifications in regions flanking the GAA repeat. In this report we show that such epigenetic changes are also present in FRDA patient brain, cerebellum and heart tissues, the primary affected systems of the disorder. Bisulfite sequence analysis of the FXN flanking GAA regions reveals a shift in the FRDA DNA methylation profile, with upstream CpG sites becoming consistently hypermethylated and downstream CpG sites becoming consistently hypomethylated. We also identify differential DNA methylation at three specific CpG sites within the FXN promoter and one CpG site within exon 1. Furthermore, we show by chromatin immunoprecipitation (ChIP) analysis that there is overall decreased histone H3K9 acetylation together with increased H3K9 methylation of FRDA brain tissue. Further studies of brain, cerebellum and heart tissues from our GAA repeat expansion-containing FRDA YAC transgenic mice reveal comparable epigenetic changes to those detected in FRDA patient tissue. We have thus developed a mouse model that will be a valuable resource for future therapeutic studies targeting epigenetic modifications of the FXN gene to increase frataxin expression

Evaluation of Power Quality Issues in grid Connected PV Systems

This paper deals with the evaluation of power quality issues in grid connected PV systems. This paper also presents  complete simulation, modeling and control of three phase grid connected solar PV module with Maximum Power Point Tracking. Perturb and Observe (P&O) method has been used for Maximum Power Point Tracking. In the proposed model DC bus voltage control , harmonic mitigation and power factor control are discussed as power quality issues. The simulation results are shown in the graphical waveforms and simulation is performed in MATLAB using SIMULINK environment and PSB toolboxes.

Optimum Power Randomization for the Minimization of Outage Probability

Cataloged from PDF version of article.The optimum power randomization problem is studied to minimize outage probability in flat block-fading Gaussian channels under an average transmit power constraint and in the presence of channel distribution information at the transmitter. When the probability density function of the channel power gain is continuously differentiable with a finite second moment, it is shown that the outage probability curve is a nonincreasing function of the normalized transmit power with at least one inflection point and the total number of inflection points is odd. Based on this result, it is proved that the optimum power transmission strategy involves randomization between at most two power levels. In the case of a single inflection point, the optimum strategy simplifies to on-off signaling for weak transmitters. Through analytical and numerical discussions, it is shown that the proposed framework can be adapted to a wide variety of scenarios including log-normal shadowing, diversity combining over Rayleigh fading channels, Nakagami-m fading, spectrum sharing, and jamming applications. We also show that power randomization does not necessarily improve the outage performance when the finite second moment assumption is violated by the power distribution of the fading. © 2013 IEEE

Possible manifestation of spin fluctuations in the temperature behavior of resistivity in Sm_{1.85}Ce_{0.15}CuO_4 thin films

A pronounced step-like (kink) behavior in the temperature dependence of resistivity $\rho (T)$ is observed in the optimally-doped $Sm_{1.85}Ce_{0.15}CuO_4$ thin films around $T_{sf}=87K$ and attributed to manifestation of strong spin fluctuations induced by $Sm^{3+}$ moments with the energy $\hbar \omega_{sf}=k_BT_{sf}\simeq 7meV$. In addition to fluctuation induced contribution $\rho_{sf}(T)$ due to thermal broadening effects (of the width $\omega_{sf}$), the experimental data are found to be well fitted accounting for residual (zero-temperature) $\rho_{res}$, electron-phonon $\rho _{e-ph}(T)=AT$ and electron-electron $\rho_{e-e}(T)=BT^2$ contributions. The best fits produced $\omega_p=2.1meV$, $\tau_0^{-1}=9.5\times 10^{-14}s^{-1}$, $\lambda =1.2$, and $E_F=0.2eV$ for estimates of the plasmon frequency, the impurity scattering rate, electron-phonon coupling constant, and the Fermi energy, respectively.Comment: 6 pages (REVTEX4), 2 EPS figures; accepted for publication in JETP Letter

The Queensland Mango Genomics Initiative

Mango is an important industry for Queensland, Australia, with an annual value exceeding $80 million. The Kensington Pride cultivar, prized by consumers for desirable taste and colour characteristics, commands 60% of the domestic market though this market share has declined in recent years as new varieties, such as Calypso™, get established with consumers. In 2005, the Queensland Government's Department of Agriculture and Fisheries commenced the Mango Genomics Initiative. This project brought together multidisciplinary teams of breeders, pathologists, sensory scientists, flavour chemists and molecular biologists to develop a suite of tools and inter-related data sets to support the accelerated development of new commercial mango varieties. An overview of the Mango Genomics Initiative will be presented here culminating in the generation of a draft Kensington Pride mango genome sequence

Mission India for Transforming Agriculture (MITrA)

Humankind’s biggest challenge in the 21st century is to ensure food and nutritional security for the growing population and improved livelihoods for smallholder farmers. World population is estimated to swell to 9.3 billion by 2050. India has to feed 1.4 billion people by 2025 and water demand for food production will increase dramatically. This challenge becomes increasingly acute in light of the depleting water resources (5177 m3 in 1951 to 1545 m3 in 2011), degrading land and increasingly variable weather associated with climate change. The Ministry of Agriculture & Farmers Welfare, Government of India has taken a novel initiative to transform agriculture in India as part of the Digital India program by transforming the rural economy and creating skilled jobs in rural areas. The Government of India has initiated various innovative schemes to enhance food production and to mitigate impacts of climate change. At the request of the Prime Minister’s Office, Government of India, to prepare a long-term strategy to increase economic opportunities for rural families in India, the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT)1 has prepared a set of six strategy papers: 1) Pulses2 2) PMKSY3) Soil Mapping4) Agri Markets5) Crop Insurance6 and 6) Digital Agriculture. The draft versions, based on the PMO request, were discussed with the Ministry of Agriculture & Farmers Welfare, Government of India7 and its senior officers made detailed suggestions to refine and strengthen these papers. This summary, elaborated in the following sections and the set of strategy papers, attached separately, incorporate the suggestions made by the Ministry officials and other leading sector-specialists from India