156 research outputs found
Criticality of tuning in athermal phase transitions
We experimentally address the importance of tuning in athermal phase
transitions, which are triggered only by a slowly varying external field acting
as tuning parameter. Using higher order statistics of fluctuations, a singular
critical instability is detected for the first time in spite of an apparent
universal self-similar kinetics over a broad range of driving force. The
results as well as the experimental technique are likely to be of significance
to many slowly driven non-equilibrium systems from geophysics to material
science which display avalanche dynamics.Comment: 5 pages, 4 figure
Benign struma ovarii-a rare monodermal ovarian teratoma-a case report
Struma ovarii is a rare ovarian tumour, first described in 1889 by Boettlin. It is defined by the presence of thyroid tissue comprising of >50% of overall mass. It comprises 1% of all ovarian tumours and 2-5% of all ovarian teratomas. Preoperative diagnosis of struma ovarii is difficult because symptoms, clinical presentation and ultrasound are often similar to that of ovarian carcinoma. Hence most of the patients are diagnosed post operatively. Most cases of strum aovarii are benign and can be treated by excision of the ovary or by unilateral salpingo-oophorectomy. In a small number of cases, there are complications, the most important being the development of malignancy or ascites associated with pleural effusion producing a pseudo-Meigs' syndrome. This is a case of struma ovary presented with features of pseudo-Meig’s syndrome. A 68 year old post-menopausal woman presented with acute abdomen and respiratory distress with an ultrasound diagnosis of ovarian torsion, ascites and pleural effusion and found to have atrial thrombus on evaluation. She had undergone staging laparotomy, TAH+ BSO, omental biopsy and peritoneal fluid cytology. Histopathology revealed predominantly benign and mature colloid filled thyroid follicles of varying sizes lined by cuboidal epithelium surrounded by lymphocytic infiltrate and congested blood vessels, which was suggestive of struma ovary.
A study of vaginal misoprostol tablet versus intra cervical dinoprostone gel for the induction of labour
Background: This was a comparative study conducted to compare the effectiveness of 25 microgram of intravaginal misoprostol with intracervical dinoprostone gel in terms of efficacy of drug, feto-maternal outcome, side effects and complications of drugs.Methods: 400 nulliparas at term, admitted for induction of labor were included in this study. They were randomly selected to receive either intravaginal misoprostol or intracervical dinoprostone gel. Group A (200 women) recieved tablet misoprostol 25 micrograms vaginally 4 hrly to a maximum of 3 doses and Group B (200 women) received dinoprostone gel 0.5mg intracervically 6 hrly to a maximum of 3 doses. Comparison was done in terms of Induction to delivery interval, need for augmentation, LSCS and instrumentation rate, need for NICU admissions and cost effectiveness.Results: The mean induction to delivery interval was less in the misoprostol group than dinoprostone group (12.5 hrs vs. 20 hrs). 78% patients delivered in the first 24 hrs in misoprostol group compared to 52 % patients in dinoprostone group. Group A had a higher success rate (81% vs.76%) and also required less augmentation of labor ( 30% vs. 60%) compared to group B. Need for LSCS was also lower in misoprostol group (11% vs. 16%). Need for instrumentation and incidence of NICU admission was similar in both groups. Misoprostol was more cost effective compared to dinoprostone.Conclusions: The misoprostol group had a shorter induction to delivery interval, more number of deliveries in the first 24 hrs of induction and a reduced need of augmentation of labor with oxytocin. There was no significant difference in the rate of caesarean section, hyper-stimulation syndrome, neonatal and maternal morbidity between the two groups. Thus, misoprosol appears to be safer, cheaper and more efficacious alternative for induction of labor especially for non-fetal indications as compared to dinoprostone gel
Application of Least Square Denoising to Improve ADMM Based Hyperspectral Image Classification
AbstractHyperspectral images contain a huge amount of spatial and spectral information so that, almost any type of Earth feature can be discriminated from any other feature. But, for this classification to be possible, it is to be ensured that there is as less noise as possible in the captured data. Unfortunately, noise is unavoidable in nature and most hyperspectral images need denoising before they can be processed for classification work. In this paper, we are presenting a new approach for denoising hyperspectral images based on Least Square Regularization. Then, the hyperspectral data is classified using Basis Pursuit classifier, a constrained L1 minimization problem. To improve the time requirement for classification, Alternating Direction Method of Multipliers (ADMM) solver is used instead of CVX (convex optimization) solver. The method proposed is compared with other existing denoising methods such as Legendre-Fenchel (LF), Wavelet thresholding and Total Variation (TV). It is observed that the proposed Least Square (LS) denoising method improves classification accuracy much better than other existing denoising techniques. Even with fewer training sets, the proposed denoising technique yields better classification accuracy, thus proving least square denoising to be a powerful denoising technique
Signature of Martensite transformation on conductivity noise in thin films of NiTi shape memory alloys
Slow time-dependent fluctuations, or noise, in the electrical resistance of
dc magnetron sputtered thin films of Nickel Titanium shape memory alloys have
been measured. Even in equilibrium, the noise was several orders of magnitude
larger than that of simple diffusive metallic films, and was found to be
non-monotonic around the martensitic transformation regime. The results are
discussed in terms of dynamics of structural defects, which also lay foundation
to a new noise-based characterization scheme of martensite transformation.Comment: 4 pages, 3 figure
Correlation of age with the size of subcortical nuclei of the brain and its implication in degenerative disease: A magnetic resonance imaging study [version 2; peer review: 2 approved]
Background Aging is a non-modifiable risk factor for neurodegenerative disease. It is well established that the brain undergoes physiological atrophy with age. So, this study was conducted to analyse the correlation between the age of the person and the size of the various subcortical nuclei of the brain and whether these measurements can serve as a useful indicator for physiological atrophy leading to degenerative disease in clinical practice. Methods A total of 600 MRI scans from healthy individuals were examined and the measurements of subcortical nuclei were taken and subsequently analysed. Results A statistically significant difference between the genders was observed in the sizes of the axial diameters of caudate nucleus, putamen and globus pallidus. Caudate nucleus transverse diameter showed a moderate negative correlation with age in males. Globus pallidus axial diameter with age showed weak positive correlation for males. Globus pallidus transverse diameter showed weak positive correlation with age for both males and females, but it was stronger for males compared to females. Conclusions These results will help neurologists and neurosurgeons in analysing various early degenerative diseases and treat them accordingly
Curvature sensing amphipathic helix in the C-terminus of RTNLB13 is conserved in all endoplasmic reticulum shaping reticulons in Arabidopsis thaliana
The reticulon family of integral membrane proteins are conserved across all eukaryotes and typically localize to the endoplasmic reticulum (ER), where they are involved in generating highly-curved tubules. We recently demonstrated that Reticulon-like protein B13 (RTNLB13) from Arabidopsis thaliana contains a curvature-responsive amphipathic helix (APH) important for the proteins’ ability to induce curvature in the ER membrane, but incapable of generating curvature by itself. We suggested it acts as a feedback element, only folding/binding once a sufficient degree of curvature has been achieved, and stabilizes curvature without disrupting the bilayer. However, it remains unclear whether this is unique to RTNLB13 or is conserved across all reticulons—to date, experimental evidence has only been reported for two reticulons. Here we used biophysical methods to characterize a minimal library of putative APH peptides from across the 21 A. thaliana isoforms. We found that reticulons with the closest evolutionary relationship to RTNLB13 contain curvature-sensing APHs in the same location with sequence conservation. Our data reveal that a more distantly-related branch of reticulons developed a ~ 20-residue linker between the transmembrane domain and APH. This may facilitate functional flexibility as previous studies have linked these isoforms not only to ER remodeling but other cellular activities
Cardio-metabolic disease risk factors among south Asian labour migrants to the Middle East: A scoping review and policy analysis
This paper aims to explore the burgeoning burden of cardiovascular and metabolic disease (CMD) risk factors among South Asian labor migrants to the Middle East. We conducted a qualitative synthesis of literature using PubMed/Medline and grey literature searches, supplemented by a policy review of policies from the South Asian countries. We found a high burden of cardio-metabolic risk factors among the migrants as well as among the populations in the home and the host countries. For example, two studies reported the prevalence of diabetes mellitus (DM) ranging between 9 and 17% among South Asian migrants. Overweight and obesity were highly prevalent amongst South Asian male migrants; prevalence ranged from 30 to 66% (overweight) and 17-80% (obesity) respectively. The home country population had a significant CMD risk factor burden. Nearly 14 to 40% have three or more risk factors: such as hypertension (17 to 37%), diabetes (3 to 7%), overweight (18 to 41%), and obesity (2 to 15%). The host country also exhibited similar burden of risk factors: hypertension (13 to 38%), diabetes (8 to 17%), overweight (33 to 77%) and obesity (35 to 41%). Only Nepal, Bangladesh and Sri Lanka have some provisions related to screening of CMDs before labor migration. Further, analysis of policy papers showed that none of the reviewed documents had requirements for screening of any specific CMDs, but chronic diseases were used generically, failing to specify specific screening target. Given the high burden of risk factors, migrants\u27 health should become an urgent priority. The lack of specific focus on screening during different stages of labor migration should receive attention. The International Labour Organization and the International Office for Migration, through their country coordination teams should engage local stakeholders to create policies and plans to address this concern. Similarly, there is a need for the host country to become an equal partner in these efforts, as migrant\u27s better cardiometabolic health is in the benefit of both host and home countries
Modelling avalanches in martensites
Solids subject to continuous changes of temperature or mechanical load often
exhibit discontinuous avalanche-like responses. For instance, avalanche
dynamics have been observed during plastic deformation, fracture, domain
switching in ferroic materials or martensitic transformations. The statistical
analysis of avalanches reveals a very complex scenario with a distinctive lack
of characteristic scales. Much effort has been devoted in the last decades to
understand the origin and ubiquity of scale-free behaviour in solids and many
other systems. This chapter reviews some efforts to understand the
characteristics of avalanches in martensites through mathematical modelling.Comment: Chapter in the book "Avalanches in Functional Materials and
Geophysics", edited by E. K. H. Salje, A. Saxena, and A. Planes. The final
publication is available at Springer via
http://dx.doi.org/10.1007/978-3-319-45612-6_
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