Iron environment non-equivalence in both octahedral and tetrahedral sites in NiFe2O4 nanoparticles: study using Mössbauer spectroscopy with a high velocity resolution

Mössbauer spectrum of NiFe2O4 nanoparticles was measured at room temperature in 4096 channels. This spectrum was fitted using various models, consisting of different numbers of magnetic sextets from two to twelve. Non-equivalence of the 57Fe microenvironments due to various probabilities of different Ni2+ numbers surrounding the octahedral and tetrahedral sites was evaluated and at least 5 different microenvironments were shown for both sites. The fit of the Mössbauer spectrum of NiFe 2O4 nanoparticles using ten sextets showed some similarities in the histograms of relative areas of sextets and calculated probabilities of different Ni2+ numbers in local microenvironments. © 2012 American Institute of Physics

Hydrostatic pressure effect on Tc of new BiS2 based Bi4O4S3 and NdO0.5F0.5BiS2 layered superconductors

We investigate the external hydrostatic pressure effect on the superconducting transition temperature (Tc) of new layered superconductors Bi4O4S3 and NdO0.5F0.5BiS2. Though the Tc is found to have moderate decrease from 4.8 K to 4.3 K (dTconset/dP = -0.28 K/GPa) for Bi4O4S3 superconductor, the same increases from 4.6 K to 5 K (dTconset/dP = 0.44 K/GPa) upto 1.31 GPa followed by a sudden decrease from 5 K to 4.7 K upto 1.75 GPa for NdO0.5F0.5BiS2 superconductor. The variation of Tc in these systems may be correlated to increase or decrease of the charge carriers in the density of states under externally applied pressure.Comment: 3 pages text +Fig

Effects of diet and/or exercise in enhancing spinal cord sensorimotor learning.

Given that the spinal cord is capable of learning sensorimotor tasks and that dietary interventions can influence learning involving supraspinal centers, we asked whether the presence of omega-3 fatty acid docosahexaenoic acid (DHA) and the curry spice curcumin (Cur) by themselves or in combination with voluntary exercise could affect spinal cord learning in adult spinal mice. Using an instrumental learning paradigm to assess spinal learning we observed that mice fed a diet containing DHA/Cur performed better in the spinal learning paradigm than mice fed a diet deficient in DHA/Cur. The enhanced performance was accompanied by increases in the mRNA levels of molecular markers of learning, i.e., BDNF, CREB, CaMKII, and syntaxin 3. Concurrent exposure to exercise was complementary to the dietary treatment effects on spinal learning. The diet containing DHA/Cur resulted in higher levels of DHA and lower levels of omega-6 fatty acid arachidonic acid (AA) in the spinal cord than the diet deficient in DHA/Cur. The level of spinal learning was inversely related to the ratio of AA:DHA. These results emphasize the capacity of select dietary factors and exercise to foster spinal cord learning. Given the non-invasiveness and safety of the modulation of diet and exercise, these interventions should be considered in light of their potential to enhance relearning of sensorimotor tasks during rehabilitative training paradigms after a spinal cord injury

Non-coding and Coding Transcriptional Profiles Are Significantly Altered in Pediatric Retinoblastoma Tumors.

Retinoblastoma is a rare pediatric tumor of the retina, caused by the homozygous loss of the Retinoblastoma 1 (RB1) tumor suppressor gene. Previous microarray studies have identified changes in the expression profiles of coding genes; however, our understanding of how non-coding genes change in this tumor is absent. This is an important area of research, as in many adult malignancies, non-coding genes including LNC-RNAs are used as biomarkers to predict outcome and/or relapse. To establish a complete and in-depth RNA profile, of both coding and non-coding genes, in Retinoblastoma tumors, we conducted RNA-seq from a cohort of tumors and normal retina controls. This analysis identified widespread transcriptional changes in the levels of both coding and non-coding genes. Unexpectedly, we also found rare RNA fusion products resulting from genomic alterations, specific to Retinoblastoma tumor samples. We then determined whether these gene expression changes, of both coding and non-coding genes, were also found in a completely independent Retinoblastoma cohort. Using our dataset, we then profiled the potential effects of deregulated LNC-RNAs on the expression of neighboring genes, the entire genome, and on mRNAs that contain a putative area of homology. This analysis showed that most deregulated LNC-RNAs do not act locally to change the transcriptional environment, but potentially function to modulate genes at distant sites. From this analysis, we selected a strongly down-regulated LNC-RNA in Retinoblastoma, DRAIC, and found that restoring DRAIC RNA levels significantly slowed the growth of the Y79 Retinoblastoma cell line. Collectively, our work has generated the first non-coding RNA profile of Retinoblastoma tumors and has found that these tumors show widespread transcriptional deregulation

A Comprehensive study on Cartilage Tympanoplasty in Adhesive Otitis Media

INTRODUCTION: The management of the atelectatic ear continues to be one of the most controversial issues facing the otolaryngologist. Much of the confusion associated with this disorder stems from a poor understanding of the underlying pathophysiologic conditions that ultimately lead to changes in the tympanic membrane, resulting in atrophy, diffuse or local retractions, and cholesteatoma formation. Likewise, the lack of an accepted classification or grading scheme for the atelectatic ear has made it difficult to elucidate and predict the natural history of this disease and effectively predict those cases that will ultimately develop complications, such as cholesteatoma. The controversy is augmented by the fact that, early in the course of the disease, and even in the presence of incus erosion, hearing loss is frequently minimal and the patient, for the most part, asymptomatic. OBJECTIVE: The surgical management of adhesive otitis media is debatable. Adhesive otitis media progressing to cholesteatoma cannot be predicted, and hearing remains normal until later in the disease course. Hence surgery is done only when there is a hearing loss or frank cholesteatoma develops, where an extensive surgery may be needed. Earlier intervention is often avoided due to near normal hearing levels at this stage in some cases. Hearing results who have undergone cartilage tympanoplasty with or without ossicular reconstruction are reported for patients with adhesive otitis media. Study design: This is a prospective study. Setting: Study was done at Madras Medical College and Rajiv Gandhi Govt General Hospital, Chennai-3. Patients: A total of 30 patients (31 ears) aged 13-48 years underwent cartilage tympanoplasty with or without ossicular reconstruction. Interventions: Tympanotomy followed by cartilage reconstruction of the tympanic membrane, with ossicular reconstruction if there is any ossicular discontinuity. Main Outcome Measure(s): Post-operative pure tone average, air-bone gap for 3 frequencies (500, 1000, 2000 Hz) compared to pre-operative levels. RESULTS: There was a statistically significant improvement in hearing. CONCLUSIONS: Management of adhesive otitis media with cartilage perichondrium tympanoplasty with or without ossiculoplasty is a proven modality of treatment with successful results. Cartilage gives a tensile strength to the tympanic membrane which prevents further retractions inspite of the continuing Eustachian tube dysfunction and thus prevents cholesteatoma formation without compromising on hearing

Traditional Goddess worship culture of Tamil society and its impact on cinematic screen portray of this generation

The life of Ancient Tamil people was beautiful and full of emotions. They were the ones who gained great knowledge and experience from every phase of their lives. The knowledge and experience conserved, concocted and passed on in fragments by older generations. The people had begun to transform their love into worship and celebration. They preserved it in various art forms such as rhetoric, storytelling, painting, sculpture, street play, drama and literature for the future generations to know and cherish it. Different forms of media play a special role in transferring the same to people. Among these, cinema holds a pivotal space. The film captures the social structure born out of the aforementioned people's faith and conveys it through its story, shedding its light in the minds of the people. It is natural for people’s overwhelming beliefs to be reflected as stories of God and Goddesses. This article describes the worship of goddesses in literature and its relation to celebrating female actors on-screen in and by a Tamil society

Morphology of supported polymer electrolyte ultra-thin films: a numerical study

Morphology of polymer electrolytes membranes (PEM), e.g., Nafion, inside PEM fuel cell catalyst layers has significant impact on the electrochemical activity and transport phenomena that determine cell performance. In those regions, Nafion can be found as an ultra-thin film, coating the catalyst and the catalyst support surfaces. The impact of the hydrophilic/hydrophobic character of these surfaces on the structural formation of the films has not been sufficiently explored yet. Here, we report about Molecular Dynamics simulation investigation of the substrate effects on the ionomer ultra-thin film morphology at different hydration levels. We use a mean-field-like model we introduced in previous publications for the interaction of the hydrated Nafion ionomer with a substrate, characterized by a tunable degree of hydrophilicity. We show that the affinity of the substrate with water plays a crucial role in the molecular rearrangement of the ionomer film, resulting in completely different morphologies. Detailed structural description in different regions of the film shows evidences of strongly heterogeneous behavior. A qualitative discussion of the implications of our observations on the PEMFC catalyst layer performance is finally proposed

Modeling and Performance Analysis of New Cuk Converter Topology for Photovoltaic Applications

Photovoltaic (PV) is a technical name in which radiant (photon) energy from the sun is converted to direct current (dc) Electrical Energy. PV power output is still low, continuous efforts are taken to develop the PV converter and controller for maximum power extracting efficiency and reduced cost factor. The maximum power point tracking (MPPT) is a process which tracks one maximum power point from array input, varying the ratio between the voltage and current delivered to get the most power it can. The selection of right converter for different application is a key factor for the optimum performance of the photo voltaic system. This paper details the study on state of the art in research works on Cuk power converters and their characteristics. A new cuk converter topology has also been proposed for the optimal performance of the photovoltaic system. Modeling of the PV array and simulation of basic cuk converter and the proposed cuk converter is carried out in Matlab/Simulink Software. Index Terms - PV Module, MPPT, Incremental Conductance (IC) Algorithm, Cuk converter, Optimal performanc

Thermo-mechanical properties of sodium chloride and alkali-treated sugarcane bagasse fibre

The experimental characterization of mechanical and thermal properties of treated and raw sugarcane bagasse fibre hasbeen studied. The bagasse fibres are treated with sodium chloride (NaCl) and sodium hydroxide (NaOH) solutions. TheNaOH treated fibres show better structural and thermal properties than other two types. SEM image of alkali-treated fibresreveals that the bundles of fibres are mainly composed of thin parenchyma cell walls. The fibres are joined with each otherwhich improves the mechanical properties. The statistical analysis is also performed using ANOVA one-factor method.From ANOVA, the significant difference between the dependent parameters and the various chemical treatments aredetermined. The results show that the NaCl and NaOH treated fibres significantly improve the mechanical properties andthermal stability

The empirical results of conditional analysis of principals' reasons in bullying teachers

Starting from the bullying of teachers by principals, this paper elaborates (a) how incompetency of management favours its emergence, (b) how teachers can see it, and (c) whether this problem affects the performance of teachers or not. The empirical results show that motivation, a positive workplace, and not being bullied or agitated by principals increase teachers' performance. The findings show that the teachers consider management's incompetency the major factor to be blamed. Collaboration between teachers can have a role in limiting this abuse. Because management is the key obligation for clearing the ethos and function of the company and clarifying the translation of words into the organization, there is some laggard of management in the way the control extracted from the structured authority is confused. Success strain!! In the light of the short- and long-term priorities and plans