87 research outputs found

    Composition dependent magnetic properties of iron oxide - polyaniline nanoclusters

    Get PDF
    Gamma - Iron Oxide prepared by sol -gel process was used to produce nanocomposites with polyaniline of varying aniline concentrations. TEM shows the presence of chain like structure for lower polyaniline concentration. The room temperature hysteresis curves show finite coercivity of 160 Oe for all the composites while the saturation magnetization was found to decrease with increasing polymer content. ZFC - FC magnetisation measurements indicate high blocking temperatures. It is believed that this indicates a strongly interacting system, which is also shown by our TEM results. Monte Carlo simulations performed on a random anisotropy model with dipolar and exchange inteactions match well with experimental results.Comment: 9 (nine) pages, 6 figures (jpeg and eps

    Magnetic properties of polypyrrole - coated iron oxide nanoparticles

    Full text link
    Iron oxide nanoparticles were prepared by sol -gel process. Insitu polymerization of pyrrole monomer in the presence of oxygen in iron oxide ethanol suspension resulted in a iron oxide - polypyrrole nanocomposite. The structure and magnetic properties were investigated for varying pyrrole concentrations. The presence of the gamma - iron oxide phase and polypyrrole were confirmed by XRD and FTIR respectively. Agglomeration was found to be comparatively much reduced for the coated samples, as shown by TEM. AC susceptibility measurements confirmed the superparamagnetic behaviour. Numerical simulations performed for an interacting model system are performed to estimate the anisotropy and compare favourably with experimental results.Comment: 11 pages,8 figure

    Antibacterial activity of methanolic and acetone extract of some medicinal plants used in indian folklore

    Get PDF
    Antibacterial study of methanolic and acetone extract in crude and treated (with 50 % lead acetate) form of medicinal plants Alstonia scholaris Linn. R.Br. (Stem bark, Apocynaceae), Achyranthus aspera Linn. (Whole plant, acantheceae), Moringa oleifera Lam. (Leaves, Morinaceae), Tinospora cordifolia (Stem, Menispermaceae), and Enicostema hyssopifolium (Willd) (Stem, Gentianaceae). Extractive values in methanol were found higher then the extractive value in acetone, for all plants. All extract of plants were tried at 40-mg/ml concentrations against eight strains of bacteria, by agarwell-difusion test. Acetone extract was found more active as compared to methanol extract. Phytochemical investigation revealed crude and treated extracts of all plants were containing more or less same type of chemical constituents (except protein and carbohydrate). Selected eight strains of bacteria were study for antibiotic susceptibility against standard antibiotics like Ampicillin (10”g), Tetracycline (25”g), Gentamicin (30”g), Co-Trimoxazole (25”g), Amikacin (10”g), by Octadisc. Treated extract of M. oleifera and A. scholaris were count as to new source of antimicrobial agent for the infectious diseases (Typhoid). Keywords: Antibacterial activity, Medicinal Plants, infectious diseases

    17ÎČ-Estradiol dysregulates innate immune responses to Pseudomonas aeruginosa respiratory infection and is modulated by estrogen receptor antagonism

    Get PDF
    ABSTRACT Females have a more severe clinical course than males in terms of several inflammatory lung conditions. Notably, females with cystic fibrosis (CF) suffer worse outcomes, particularly in the setting of Pseudomonas aeruginosa infection. Sex hormones have been implicated in experimental and clinical studies; however, immune mechanisms responsible for this sex-based disparity are unknown and the specific sex hormone target for therapeutic manipulation has not been identified. The objective of this study was to assess mechanisms behind the impact of female sex hormones on host immune responses to P. aeruginosa . We used wild-type and CF mice, which we hormone manipulated, inoculated with P. aeruginosa , and then examined for outcomes and inflammatory responses. Neutrophils isolated from mice and human subjects were tested for responses to P. aeruginosa . We found that female mice inoculated with P. aeruginosa died earlier and showed slower bacterial clearance than males ( P &lt; 0.0001). Ovariectomized females supplemented with 17ÎČ-estradiol succumbed to P. aeruginosa challenge earlier than progesterone- or vehicle-supplemented mice ( P = 0.0003). 17ÎČ-Estradiol-treated ovariectomized female mice demonstrated increased lung levels of inflammatory cytokines, and when rendered neutropenic the mortality difference was abrogated. Neutrophils treated with 17ÎČ-estradiol demonstrated an enhanced oxidative burst but decreased P. aeruginosa killing and earlier cell necrosis. The estrogen receptor (ER) antagonist ICI 182,780 improved survival in female mice infected with P. aeruginosa and restored neutrophil function. We concluded that ER antagonism rescues estrogen-mediated neutrophil dysfunction and improves survival in response to P. aeruginosa . ER-mediated processes may explain the sex-based mortality gap in CF and other inflammatory lung illnesses, and the ER blockade represents a rational therapeutic strategy. </jats:p

    Intrusion Detection Recording System with Biometric Lock

    Get PDF
    We are coming across cases, where the education system is being distorted and perverted. As the present security of our education system has several loopholes that can be exploited to obtain access to the locations were question papers are being kept, posing a significant threat to society, to address this problem we engineered an intrusion detection recording system with a biometric lock. Our project is a result of combination of two already existing methodologies – Wireless Biometric Lock and Noise detector with automatic recording system. This combination provides us with a more secure system than the existing individual implementation. Thus, our project is a noise sensor-based device&nbsp;with an automatic recording system that can also lock the locker or door using a fingerprint-based biometric interface which not only detects intrusion but also traps the person who tries to intrude

    The Perceived Tightness Scale Does Not Provide Reliable Estimates of Blood Flow Restriction Pressure.

    Get PDF
    CONTEXT: The perceived tightness scale is suggested to be an effective method for setting subocclusive pressures with practical blood flow restriction. However, the reliability of this scale is unknown and is important as the reliability will ultimately dictate the usefulness of this method. OBJECTIVE: To determine the reliability of the perceived tightness scale and investigate if the reliability differs by sex. DESIGN: Within-participant, repeated-measures. SETTING: University laboratory. PARTICIPANTS: Twenty-four participants (12 men and 12 women) were tested over 3 days. MAIN OUTCOME MEASURES: Arterial occlusion pressure (AOP) and the pressure at which the participants rated a 7 out of 10 on the perceived tightness scale in the upper arm and upper leg. RESULTS: The percentage coefficient of variation for the measurement was approximately 12%, with no effect of sex in the upper (median ÎŽ [95% credible interval]: 0.016 [-0.741, 0.752]) or lower body (median ÎŽ [95% credible interval]: 0.266 [-0.396, 0.999]). This would produce an overestimation/underestimation of ∌25% from the mean perceived pressure in the upper body and ∌20% in the lower body. Participants rated pressures above their AOP for the upper body and below for the lower body. At the group level, there were differences in participants\u27 ratings for their relative AOP (7 out of 10) between day 1 and days 2 and 3 for the lower body, but no differences between sexes for the upper or lower body. CONCLUSIONS: The use of the perceived tightness scale does not provide reliable estimates of relative pressures over multiple visits. This method resulted in a wide range of relative AOPs within the same individual across days. This may preclude the use of this scale to set the pressure for those implementing practical blood flow restriction in the laboratory, gym, or clinic

    The perceived tightness scale does not provide reliable estimates of blood flow restriction pressure

    Get PDF
    © 2020 Human Kinetics, Inc. Context: The perceived tightness scale is suggested to be an effective method for setting subocclusive pressures with practical blood flow restriction. However, the reliability of this scale is unknown and is important as the reliability will ultimately dictate the usefulness of this method. Objective: To determine the reliability of the perceived tightness scale and investigate if the reliability differs by sex. Design: Within-participant, repeated-measures. Setting: University laboratory. Participants: Twenty-four participants (12 men and 12 women) were tested over 3 days. Main Outcome Measures: Arterial occlusion pressure (AOP) and the pressure at which the participants rated a 7 out of 10 on the perceived tightness scale in the upper arm and upper leg. Results: The percentage coefficient of variation for the measurement was approximately 12%, with no effect of sex in the upper (median ÎŽ [95% credible interval]: 0.016 [-0.741, 0.752]) or lower body (median ÎŽ [95% credible interval]: 0.266 [-0.396, 0.999]). This would produce an overestimation/underestimation of ∌25% from the mean perceived pressure in the upper body and ∌20% in the lower body. Participants rated pressures above their AOP for the upper body and below for the lower body. At the group level, there were differences in participants’ ratings for their relative AOP (7 out of 10) between day 1 and days 2 and 3 for the lower body, but no differences between sexes for the upper or lower body. Conclusions: The use of the perceived tightness scale does not provide reliable estimates of relative pressures over multiple visits. This method resulted in a wide range of relative AOPs within the same individual across days. This may preclude the use of this scale to set the pressure for those implementing practical blood flow restriction in the laboratory, gym, or clinic

    Applying Satellite Observations of Tropical Cyclone Internal Structures to Rapid Intensification Forecast With Machine Learning

    Get PDF
    Tropical cyclone (TC) intensity change is controlled by both environmental conditions and internal storm processes. We show that TC 24‐hr subsequent intensity change (DV24) is linearly correlated with the departures in satellite observations of inner‐core precipitation, ice water content, and outflow temperature from respective threshold values corresponding to neutral TCs of nearly constant intensity. The threshold values vary linearly with TC intensity. Using machine learning with the inner‐core precipitation and the predictors currently employed at the National Hurricane Center (NHC) for probabilistic rapid intensification (RI) forecast guidance, our model outperforms the NHC operational RI consensus in terms of the Peirce Skill Score for RI in the Atlantic basin during 2009–2014 by 37%, 12%, and 138% for DV24 ≄ 25, 30, and 35 kt, respectively. Our probability of detection is 40%, 60%, and 200% higher than the operational RI consensus, while the false alarm ratio is only 4%, 7%, and 6% higher

    ‘I arranged my own marriage': arranged marriages and post-colonial feminism

    Get PDF
    This article looks at the practice of arranged marriage among women of Indian, Pakistani and Bangladeshi origin resident in Britain. It examines the conflation of arranged marriages with forced marriages and the assumption that arranged marriages are examples of cultural practices that thwart individual agency. Drawing upon original empirical data, this article will argue that in the practice of arranged marriage, some South Asian women are able to exercise agency while choosing their marriage partner. They adapt traditional arranged marriage practices to navigate their way around strict cultural expectations and to negotiate with their family members the choice of a match that is favourable for them. It provides a corrective account of arranged marriages by challenging the stereotype of the ‘oppressed third world women' and their experiences of such marriages. The article will do this by employing the idea of post-colonial feminism and by highlighting two long-standing issues in feminist debates: the idea of agency and the conception and role of power in the struggle for women's rights. It will make a case for a post-colonial approach to feminism as one way of reconciling feminism with the politics of multiculturalism
    • 

    corecore