250 research outputs found
Comparison of 16S rRNA gene sequences of genus Methanobrevibacter
BACKGROUND: The phylogeny of the genus Methanobrevibacter was established almost 25 years ago on the basis of the similarities of the 16S rRNA oligonucleotide catalogs. Since then, many 16S rRNA gene sequences of newly isolated strains or clones representing the genus Methanobrevibacter have been deposited. We tried to reorganize the 16S rRNA gene sequences of this genus and revise the taxonomic affiliation of the isolates and clones representing the genus Methanobrevibacter. RESULTS: The phylogenetic analysis of the genus based on 786 bp aligned region from fifty-four representative sequences of the 120 available sequences for the genus revealed seven multi-member groups namely, Ruminantium, Smithii, Woesei, Curvatus, Arboriphilicus, Filiformis, and the Termite gut symbionts along with three separate lineages represented by Mbr. wolinii, Mbr. acididurans, and termite gut flagellate symbiont LHD12. The cophenetic correlation coefficient, a test for the ultrametric properties of the 16S rRNA gene sequences used for the tree was found to be 0.913 indicating the high degree of goodness of fit of the tree topology. A significant relationship was found between the 16S rRNA sequence similarity (S) and the extent of DNA hybridization (D) for the genus with the correlation coefficient (r) for logD and logS, and for [ln(-lnD) and ln(-lnS)] being 0.73 and 0.796 respectively. Our analysis revealed that for this genus, when S = 0.984, D would be <70% at least 99% of the times, and with 70% D as the species "cutoff", any 16S rRNA gene sequence showing <98% sequence similarity can be considered as a separate species. In addition, we deduced group specific signature positions that have remained conserved in evolution of the genus. CONCLUSIONS: A very significant relationship between D and S was found to exist for the genus Methanobrevibacter, implying that it is possible to predict D from S with a known precision for the genus. We propose to include the termite gut flagellate symbiont LHD12, the methanogenic endosymbionts of the ciliate Nyctotherus ovalis, and rat feces isolate RT reported earlier, as separate species of the genus Methanobrevibacter
Anisotropic Compact Star Model on Finch-Skea Spacetime
In this study, we demonstrate a new anisotropic solution to the Einstein
field equations in Finch-Skea spacetime. The physical features of stellar
configuration are studied in previous investigations. We create a model that
meets all physical plausibility conditions for a variety of stars and plot
graphs for \textbf{4U 1820-30}.Comment: 9 figures, 1 table and 7 page
Study of various reasons for interruption of anti-tubercular treatment in patients of tuberculosis reporting to tertiary care center of west Rajasthan
Background: Tuberculosis is a major cause of death in India. Premature cessation of treatment in tuberculosis patient is a leading cause for developing MDR (multidrug resistant tuberculosis) as well as a major threat to control programs. Despite the easy approach and free of cost, availability to antitubercular medicines the interruptions of the treatment are still on a high. So, we analyzed such various reasons leading to interrupt the antitubercular treatment.Methods: Total 150 patients who interrupted the antitubercular treatment, were interviewed with a predesigned questionnaire and the result was analyzed.Results: Out of total 150 patients 115 (76.7%) male and 35 (23.3%) female were interviewed, who were having history of antitubercular treatment interruption. Out of 150 patients, 79 (52.7%) patients stopped their treatment because of improvement. Total 25 (16.7%) patients had stopped their treatment because of high cost, 16 (10.7%) due to personal/family reason, 17 (11.4%) patients had stopped their treatment due to nausea/vomiting/anorexia, 5 (3.3%) due to alcoholism/drug or other addiction, 2 (1.3%) patients had stopped their treatment because they were advised to stop it by health personnel and long distance travelled to take drugs.Conclusions: Improvement of symptoms was the most common reason in patients who received DOTS treatment and high cost of treatment in patients who received non DOTS treatment. Poor education and socioeconomic status of society are the other reasons for possible treatment interruptions because as soon as the patient improves, they move out to earn their wages to run the family with the unavoidable default from the treatment
Vacuum Stability in Inert Higgs Doublet Model with Right-handed Neutrinos
We analyze the vacuum stability in the inert Higgs doublet extension of the
Standard Model (SM), augmented by right-handed neutrinos (RHNs) to explain
neutrino masses at tree level by the seesaw mechanism. We make a comparative
study of the high- and low-scale seesaw scenarios and the effect of the Dirac
neutrino Yukawa couplings on the stability of the Higgs potential. Bounds on
the scalar quartic couplings and Dirac Yukawa couplings are obtained from
vacuum stability and perturbativity considerations. The regions corresponding
to stability, metastability and instability of the electroweak vacuum are
identified. These theoretical constraints give a very predictive parameter
space for the couplings and masses of the new scalars and RHNs which can be
tested at the LHC and future colliders. The lightest non-SM neutral CP-even/odd
scalar can be a good dark matter candidate and the corresponding collider
signatures are also predicted for the model.Comment: 38 pages and 44 figures, citation and text added, JHEP accepted
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Superconductivity with high upper critical field in Ta-Hf Alloys
High upper-critical field superconducting alloys are required for
superconducting device applications. In this study, we extensively
characterized the structure and superconducting properties of alloys Ta
Hf (x = 0.2, 0.4, 0.5, 0.6 and 0.8). The substitution of Hf (T =
0.12 K, type-I superconductor) with Ta (T = 4.4 K, type-I superconductor)
shows an anomalous enhancement of T with variation of composition.
Interestingly, all compositions exhibited strongly coupled bulk type-II
superconductivity with a high upper critical field. In particular, for
compositions x = 0.2, and 0.4, the upper critical field (H) approached
the Pauli limiting field.Comment: 8 pages, 6 figure
Comparative Analysis of Speech Emotion Recognition Models and Technique
Speech Emotion Recognition (SER) refers to accurately predicting human emotions from their speech. The ability to predict emotions through speech signals is a motivating factor in achieving Human-Computer Interaction (HCI). This paper contains a comparative study of the existing research on speech emotion models. It makes use of the RAVDESS and SAVEE dataset containing audio input. The study of speech emotion recognition is made on SVM, CNN, KNN, MLP, Decision Tree, XGBoost, and Random Forest models. This paper presents a comparative analysis of the models highlighting the accuracy, F1 Score, bar plots, and loss graphs of the same. The paper also highlights the significant future areas for study in speech emotion recognition
RF Controlled Robotic Vehicle with Metal Detection Project
The project is intended to cultivate a robotic vehicle that can sense metals ahead of it on its path similar to detecting land mines. The robot is controlled by a remote using RF technology. It consists of a metal detector circuit interfaced to the control unit that alarms the user behind it about a doubted land mine ahead. An 8051 series of microcontroller is used for the preferred operation.
For controlling the movement of robot either to forward, backward & right or left commands are sent to the receiver by using push buttons of the transmitter. At the receiving end two motors are interfaced to the microcontroller where they are used for the movement of the vehicle. The RF transmitter acts as a RF remote control that has the advantage of sufficient range (up to 200 meters) with proper antenna, while the receiver decodes before serving it to another microcontroller to drive DC motors via motor driver IC for necessary work. A metal detector circuit is attached on the robot body and its operation is carried out automatically on sensing any metal underneath. The instant the robot senses this metal it produces an alarm sound through buzzer. This is to aware the operator of a probable metal (eg: land mine) ahead on its path.
Further the project can be enhanced by mounting a wireless camera on the robot so that the operator can govern the movement of the robot remotely by observing it on a screen
Domain fluctuations in a ferroelectric low-strain BaTiO3 thin film
A ferroelectric BaTiO3 thin film grown on a NdScO3 substrate was studied using x-ray photon correlation spectroscopy (XPCS) to characterize thermal fluctuations near the a/b to a/c domain structure transformation present in this low-strain material, which is absent in the bulk. XPCS studies provide a direct comparison of the role of domain fluctuations in first- and second-order phase transformations. The a/b to a/c domain transformation is accompanied by a decrease in fluctuation timescales, and an increase in intensity and correlation length. Surprisingly, domain fluctuations are observed up to 25 degrees C above the transformation, concomitant with the growth of a/c domains and coexistence of both domain types. After a small window of stability, as the Curie temperature is approached, a/c domain fluctuations are observed, albeit slower, potentially due to the structural transformation associated with the ferroelectric to paraelectric transformation. The observed time evolution and reconfiguration of domain patterns highlight the role played by phase coexistence and elastic boundary conditions in altering fluctuation timescales in ferroelectric thin films
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