Arrhythmogenic or dilated or desmoplakin cardiomyopathy? A challenging case managed by our multidisciplinary cardiogenetic team.

Arrhythmogenic cardiomyopathy (ACM), characterized by fibro or fibrofatty infiltration of the myocardium with a predominant arrhythmic presentation, is a genetically mediated cause of sudden cardiac death in the young and athletic individuals. We report a case of a severe form of biventricular ACM in a middle-aged man with a family history of cardiomyopathy-related young death. The proband was identified to harbor two novel mutations in the DES and DOLK genes and was managed comprehensively with a multidisciplinary team approach. This report reinforces the need for a dedicated cardiovascular genetics program as well as a population-specific genetic database in developing countries.

Brain Tumor Detection and Segmentation by Intensity Adjustment.

In recent years, Brain tumor detection and segmentation has created an interest on research areas. The process of identifying and segmenting brain tumor is a very tedious and time consuming task, since human physique has anatomical structure naturally. Magnetic Resonance Image (MRI) scan analysis is a powerful tool that makes effective detection of the abnormal tissues from the brain. Among different techniques, Magnetic Resonance Image (MRI) is a liable one which contains several modalities in scanning the images captured from interior structure of human brain. A novel hybrid energy-efficient method is proposed for automatic tumor detection and segmentation. The proposed system follows K-means clustering, integrated with Fuzzy C-Means (KMFCM) and active contour by level set for tumor segmentation. An effective segmentation, edge detection and intensity enhancement can detect brain tumor easily. For that, active contour with level set method has been utilized. The performance of the proposed approach has been evaluated in terms of white pixels, black pixels, tumor detected area, and the processing time. This technique can deal with a higher number of segmentation problem and minimum execution time by ensuring segmentation quality. Additionally, tumor area length in vertical and horizontal positions is determined to measure sensitivity, specificity, accuracy, and similarity index values. Further, tumor volume is computed. Knowledge of the information of tumor is helpful for the physicians for effective diagnosing in tumor for treatments. The entire experimentation was implemented in MATLAB environment and simulation results were compared with existing approaches.

Myocardial infarction following bee sting.

Bee stings are commonly encountered worldwide. Various manifestations after bee sting have been described. Local reactions are common. Unusually, manifestations like vomiting, diarrhoea, dyspnoea, generalised oedema, acute renal failure, hypotension and collapse may occur. Rarely vasculitis, serum sickness, neuritis and encephalitis have been described which generally develop days to weeks after a sting. Acute coronary syndromes after hymenoptera stings and other environmental exposures are referred to as the Kounis syndrome or allergic myocardial ischaemia and infarction. We report a 60 year old male who developed myocardial infarction after multiple bee stings over his body.

Results of comprehensive genetic testing in patients presenting to a multidisciplinary inherited heart disease clinic in India.

OBJECTIVES: This study aims to analyze the results of comprehensive genetic testing in patients presenting to a dedicated multidisciplinary inherited heart disease clinic in India. METHODS: All patients presenting to our clinic from August 2017 to October 2023 with a suspected inherited heart disease and consenting for genetic testing were included. The probands were grouped into familial cardiomyopathies namely hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), arrhythmogenic cardiomyopathy (ACM) and peripartum cardiomyopathy (PPCM), channelopathies namely congenital long QT syndrome (LQTS) and Brugada syndrome (BrS), and heritable connective tissue disorder namely Marfan Syndrome (MFS). Next generation sequencing (NGS) was used, and pre-test and post-test counseling were provided to probands and cascade screening offered to relatives. RESULTS: Mean age of the subjects (n = 77; 48 probands, 29 relatives) was 43 ± 18 years, 68 % male and 44 % symptomatic, with 36 HCM, 3 DCM, 3 ACM, 1 PPCM, 3 LQTS, 1 BrS and 1 MFS probands. The diagnostic yield of NGS-based genetic testing was 31 %; variants of uncertain significance (VUS) were identified in 54 %; and 15 % were genotype-negative. Twenty-nine relatives from 18 families with HCM (n = 12), DCM (n = 3), ACM (n = 2) and MFS (n = 1) underwent genetic testing. The genotype positive probands/relatives and VUS carriers with strong disease phenotype and/or high risk variant were advised periodic follow-up; the remaining probands/relatives were discharged from further clinical surveillance. CONCLUSIONS: Genetic testing guides treatment and follow-up of patients with inherited heart diseases and should be carried out in dedicated multidisciplinary clinics with expertise for counseling and cascade screening of family members.

Local structural studies of the cubic Cd1-xCaxO system through Cd K-edge extended X-ray absorption spectroscopic studies.

Cd K-edge extended X-ray absorption fine-structure spectroscopic studies were carried out on Cd(1-x)Ca(x)O (0 ≤ x ≤0.9) solid solutions and the first and second nearest neighbour (NN) distances and their mean square relative displacement σ(2) were estimated. The first NN distance, d(Cd-O)(x), was found to be smaller than its expected value, a(x)/2, obtained from the X-ray diffraction measurements. It increases monotonically and non-linearly with a negative curvature, comparable with that of the a(x) value variation. The variation σ(2) of the 1NN with x is consistent with a disordered solid solution model. The 2NN distances d(Cd-Cd)(x) and d(Cd-Ca)(x) are found to follow the average values obtained by X-ray diffraction with d(Cd-Ca)(x) > d(Cd-Cd)(x). From detailed analysis it is argued that the solid solution exhibits a bimodal distribution of the 1NN distances, d(Cd-O)(x) and d(Ca-O)(x), and that the system belongs to a persistent type.

UV induced zener diode characteristic in a single n-ZnO/p++-Si nanoheterojunction.

Rectification is observed in a single n-ZnO/p++-Si nanoheterojunction using ultra high vacuum compatible scanning tunneling microscope. The nanohetrojunctions have been grown using catalyst free vapor-solid growth of ZnO nanorods on p++-Si substarte. A high rectification ratio approximately 100 at 2 V is observed in the current voltage measurements. Temperature dependent study in these nanohetero-junctions showed activation energy for carrier conduction approximately 66 meV, which is primarily associated to the presence of heterojunction induced interface states. Role of ultra violet excitation on these finite sized (approximately 500 nm) nanoheterojunction is also studied with photo-generated electron-hole pairs. A Zener breakdown is observed in this photo-excitation process. Increase in the concentration of minority carriers and corresponding decrease in barrier width and height at the junction have been identified for the observed tunneling behavior under UV illumination. The large carrier concentration in the finite sized device with large diffusion length of electron (approximately 2 microm) is made responsible for the observed voltage regulation.

Stroke after multiple bee sting.

Bee stings are commonly encountered worldwide. Various manifestations after bee sting have been described. Local reactions are common. Unusually, manifestations like vomiting, diarrhea, dyspnea, generalized edema, acute renal failure, hypotension and collapse may occur. Rarely vasculitis, serum sickness, neuritis and encephalitis have been described which generally develop days to weeks after a sting. We report a case of a 25-year-old male who developed left sided monoparesis and transient visual loss following multiple bee stings. Unlike the previous case reports, in our case there has been involvement of both the anterior circulation and posterior circulation territory to the brain. We report this case due to it's rarity.

SecDedoop: Secure Deduplication with Access Control of Big Data in the HDFS/Hadoop Environment.

With the rapid growth of storage providers, data deduplication is an essential storage optimization technique that greatly minimizes data storage costs by storing a unique copy of duplicate data. Nowadays, deduplication introduces various new challenges such as security and insufficient space issue. Hence, in this article, we propose a secure data deduplication with access control of big data over HDFS (Hadoop Distributed File System)/Hadoop environment, called SecDedoop. First, the system achieves security for data confidentiality by third party vendor using elliptic curve cryptography. There are two types of keys (public key and private key) generated for data retrieval. Second, we consider data deduplication. The user's original file is divided into a number of equal chunks. Then, each chunk (e.g., 1. txt) is tokenized into words and the weight of words is computed by using TF-IDF frequency. The SHA-3 hash computation is performed to the user's original file. If the hash value is not duplicate, then we store data in HDFS. The PSO (particle swarm optimization)-based MapReduce model is the proposed best data node selection. Initially, MapReduce process is finished for the user's original file and it results in the best set of data nodes; then, we apply PSO to compute the fitness value for best data node selection. Further, we consider MongoDB for fast indexing of the user's original files and also apply FCM (fuzzy-C-means clustering) for clustering the user's files. In this article, we consider the modified version of PSO and FCM to eliminate the open issues in conventional PSO and FCM. The performance of our proposed SecDedoop has been evaluated by using various performance metrics and also proved it outperforms better than previous approaches.

Temperature dependence of phonon modes in nanocrystalline La0.67ca0.33MnO3 as observed by infrared spectroscopy.

Low temperature infrared absorption measurements have been carried out on nanocrystalline La0.67Ca0.33MnO3 powder across the magnetic and the insulator-to-metal phase transitions. Interesting changes are observed in the temperature dependence of the mid-IR polaronic background and the stretching mode of the MnO, octahedron. Upon cooling below 250 K, the overall absorbance increases, but, unlike in the case of microcrystalline LCMO, the stretching mode is not completely screened even at 5 K. The temperature dependence of the stretching mode parameters points to a much reduced phonon-polaron coupling as compared to that in the bulk material.

Studies of local structure at Zr sites in pressure amorphized zirconium tungstate.

Amorphous to crystalline transition in pressure quenched Zr(0.5)Hf(0.5)W(2)O(8) has been studied with respect to local structures of ZrO(6) using the perturbed angular correlation technique. In an untreated crystalline sample close to 0.7 fraction of the probe atoms occupy Zr sites of regular ZrO(6) while the remaining three fractions are understood to be associated with contracted and distorted octahedra. The existence of six distinct ZrO(6) could be deduced based on perturbed angular correlation studies in the pressure amorphized sample. In the amorphous sample these ZrO(6) are associated with appreciable octahedral distortions. Isochronal annealing measurements show that these octahedra remain structurally quite stable up to 800 K. Values of quadrupole frequencies tend to become close to those experienced by probe atoms in a crystalline sample for annealing at 870 K, implying that around this temperature there is an onset of amorphous to crystalline transition. Complete restoration of quadrupole parameters to those of the untreated crystalline sample is seen subsequent to annealing at 975 K.

Evaluation of the hypothalamo-pituitary-adrenal axis during the post-COVID-19 period in patients treated with steroids during the illness

ABSTRACT Objective: COVID-19 is a multisystem immunoinflammatory disorder, and the hypothalamo-pituitary-adrenal (HPA) axis may be affected by SARS-CoV-2 as well as by steroid treatment during the illness. Information on the HPA axis after recovering from COVID-19, especially in those treated with steroids, is sparse. Hence, this study was performed to evaluate the hypothalamo-pituitary-adrenal axis during the post-COVID-19 period in patients treated with steroids during the illness. Subject and methods: This prospective study involved 60 patients aged 18-60 years who had recovered from moderate or severe COVID-19 and had received steroid treatment during the illness. The HPA axis was assessed with a low-dose (1 mcg) adrenocorticotropic hormone stimulation test at 3, 6 and 9 months in the post-COVID period. Results: The HPA axis was suppressed in 31.66% of the patients at 3 months and 5% at 6 months; however, all patients recovered at 9 months. Cumulative steroid use during the illness was inversely correlated with stimulated cortisol at 3 months in the post-COVID period. Fatigue was present in 58.33% of the patients at 3 months and was more prevalent in those with HPA axis suppression. Conclusion: Nearly one-third of the patients with moderate to severe COVID-19 who were treated with steroids had suppressed HPA axis at 3 months, with gradual recovery over a period of 9 months. Cumulative steroid equivalent dose, but not disease severity, was predictive of HPA axis suppression at 3 months.

Spectroscopic characterization of nanocrystalline chromium nitride (CrN).

Nanocrystalline chromiuim nitride has been synthesised by direct gas phase nitridation of nanocrystalline chromia at 1100 degrees C in ammonia-atmosphere. XRD of this material showed formation of single phase CrN with particle size around 20 nm. AFM studies showed particle distribution along with some soft agglomerated nanostructures. Nanocrystalline Cr2O3 and partially-as well as fully--converted nanocrystalline CrN were also investigated using various spectroscopic techniques like XPS, FT-IR, and Raman for gaining insight into the conversion pathways. Spectroscopic investigations of these materials clearly indicate that complete conversion of CrN occurs by nitriding at 1100 degrees C for 4 hrs. The salient spectroscopic features of these nanocrystalline materials with respect to their microcrystalline counterparts are discussed.

Competing magnetic phases in La(0.7)Sr(0.3)MnO(3) as deduced from Mn site hyperfine parameters.

Time differential perturbed angular correlation measurements using the (181)Ta probe in La(0.7)Sr(0.3)Mn(0.995)Hf(0.005)O(3) reveal the presence of two distinct hyperfine components, identified with probe atoms occupying Mn sites which are rich and deficient in hole concentration. The Mn(4+) rich zones exhibit ferromagnetic ordering at all temperatures below 360 K, the bulk Curie temperature. In the case of Mn(4+) deficient zones, the paramagnetic order is seen to evolve into a canted antiferromagnetic ordering below 360 K, that becomes ferromagnetic below 250 K. Concomitantly, there is a change in the fractions below 250 K. The implications of these results are discussed in terms of electronic phase separation.

Magneto-transport behaviour of Bi2Se3-xTex : role of disorder.

Magneto-resistance and Hall resistance measurements have been carried out in fast-cooled single crystals of Bi2Se3-xTex (x = 0 to 2) in 4-300 K temperature range, under magnetic fields up to 15 T. The variation of resistivity with temperature that points to a metallic behaviour in Bi2Se3, shows an up-turn at low temperatures in the Te doped samples. Magneto-resistance measurements in Bi2Se3 show clear signatures of Shubnikov-de Hass (SdH) oscillations that gets suppressed in the Te doped samples. In the Bi2SeTe2 sample, the magneto-resistance shows a cusp like positive magneto-resistance at low magnetic fields and low temperatures, a feature associated with weak anti-localisation (WAL), that crosses over to negative magneto-resistance at higher fields. The qualitatively different magneto-transport behaviour seen in Bi2SeTe2 as compared to Bi2Se3 is rationalised in terms of the disorder, through an estimate of the carrier density, carrier mobility and an analysis in terms of the Ioffe-Regel criterion with support from Hall Effect measurements. We demonstrate that by introducing Te, in the strongly disordered samples a smooth crossover of SdH and WAL can be seen in the Bi2Se3-xTex series, both of which provide signatures for the presence of topological surface states.

Structural investigations in BaFe(2-x)Ru(x)As2 as a function of Ru and temperature.

We present the results of synchrotron X-ray diffraction (XRD) measurements on powdered single-crystal samples of BaFe(2-x)Ru(x)As2, as a function of Ru content, and as a function of temperature, across the spin-density wave transition in BaFe(1.9)Ru(0.1)As2. The Rietveld refinements reveal that with Ru substitution, while the a-axis increases, the c-axis decreases. In addition, the variation of positional coordinates of As (z(As)), the Fe-As bond length and the As-Fe-As bond angles have also been determined. In the sample with x = 0.1, temperature-dependent XRD measurements indicate that the orthorhombicity shows the characteristic increase with a decrease in temperature, below the magnetic transition. It is seen that the c-axis, the As-Fe-As bond angles, Fe-As bond length and positional coordinates of the As show definite anomalies close to the structural transition. The observed anomalies in structural parameters are analysed in conjunction with restricted geometric optimization of the structure using ab initio electronic structure calculations.

Quantification of oxide particle composition in model oxide dispersion strengthened steel alloys.

Oxide dispersion strengthened ferritic steels (ODS) are being considered for structural components of future designs of fission and fusion reactors because of their impressive high-temperature mechanical properties and resistance to radiation damage, both of which arise from the nanoscale oxide particles they contain. Because of the critical importance of these nanoscale phases, significant research activity has been dedicated to analysing their precise size, shape and composition (Odette et al., Annu. Rev. Mater. Res. 38 (2008) 471-503 [1]; Miller et al., Mater. Sci. Technol. 29(10) (2013) 1174-1178 [2]). As part of a project to develop new fuel cladding alloys in India, model ODS alloys have been produced with the compositions, Fe-0.3Y2O3, Fe-0.2Ti-0.3Y2O3 and Fe-14Cr-0.2Ti-0.3Y2O3. The oxide particles in these three model alloys have been studied by APT in their as-received state and following ion irradiation (as a proxy for neutron irradiation) at various temperatures. In order to adequately quantify the composition of the oxide clusters, several difficulties must be managed, including issues relating to the chemical identification (ranging and variable peak-overlaps); trajectory aberrations and chemical structure; and particle sizing. This paper presents how these issues can be addressed by the application of bespoke data analysis tools and correlative microscopy. A discussion follows concerning the achievable precision in these measurements, with reference to the fundamental limiting factors.

Effect of surface stress on microcantilever resonance frequency during water adsorption: influence of microcantilever dimensions.

This paper reports the effect of dimensions of microcantilever (MC) on its resonance frequency and bending upon adsorption of water molecules. Study is conducted on three MCs having the dimensions of 450 × 40 × 2.5 µm(3) (MC1), 225 × 30 × 3 µm(3) (MC2) and 125 × 35 × 4.5 µm(3) (MC3). The measured resonant frequency showed the expected negative shift in MC1, initially positive followed by a negative shift in MC2 and only positive shift in MC3 during adsorption. This behavior is attributed to changes in the stiffness of the MC associated with the surface stress. The surface stress generated on the MC has been derived from its bending measurements upon water adsorption. The change in the stiffness of MC evaluated from an independent estimate of expected frequency shift showed that the relative stiffness change of MC increases linearly with the surface stress scaled with cube of width to height ratio of MCs, confirming the dimensional dependence of adsorption induced stiffness change.

Baseline drift removal and denoising of MCG data using EEMD: role of noise amplitude and the thresholding effect.

We adopt the Ensemble Empirical Mode Decomposition (EEMD) method, with an appropriate thresholding on the Intrinsic Mode Functions (IMFs), to denoise the magnetocardiography (MCG) signal. To this end, we discuss the two associated problems that relate to: (i) the amplitude of noise added to the observed signal in the EEMD method with a view to prevent mode mixing and (ii) the effect of direct thresholding that causes discontinuities in the reconstructed denoised signal. We then denoise the MCG signals, having various signal-to-noise ratios, by using this method and compare the results with those obtained by the standard wavelet based denoising method. We also address the problem of eliminating the high frequency baseline drift such as the sudden and discontinuous changes in the baseline of the experimentally measured MCG signal using the EEMD based method. We show that the EEMD method used for denoising and the elimination of baseline drift is superior in performance to other standard methods such as wavelet based techniques and Independent Component Analysis (ICA).