56 research outputs found

    Pressure-Induced Topological Phase Transitions in CdGeSb2_2 and CdSnSb2_2

    Full text link
    Topological quantum phase transitions (TQPTs) in a material induced by external perturbations are often characterized by band touching points in the Brillouin zone. The low-energy excitations near the degenerate band touching points host different types of fermions while preserving the topological protection of surface states. An interplay of different tunable topological phases offers an insight into the evolution of the topological character. In this paper, we study the occurrence of TQPTs as a function of hydrostatic pressure in CdGeSb2_2 and CdSnSb2_2 chalcopyrites, using the first-principles calculations. At ambient pressure, both materials are topological insulators having a finite band gap with inverted order of Sb-ss and Sb-pxp_x,pyp_y orbitals of valence bands at the Γ\Gamma point. On the application of hydrostatic pressure the band gap reduces, and at the critical point of the phase transition, these materials turn into Dirac semimetals. On further increasing the pressure beyond the critical point, the band inversion is reverted making them trivial insulators. The pressure-induced change in band topology from non-trivial to trivial phase is also captured by L\"{u}ttinger model Hamiltonian calculations. Our model demonstrates the critical role played by a pressure-induced anisotropy in frontier bands in driving the phase transitions. These theoretical findings of peculiar coexistence of multiple topological phases in the same material provide a realistic and promising platform for the experimental realization of the TQPT.Comment: 7 pages, 7 figure

    Directions for testing cream

    Get PDF
    Caption title

    A Novel Approach for Clustering Big Data based on MapReduce

    Get PDF
    Clustering is one of the most important applications of data mining. It has attracted attention of researchers in statistics and machine learning. It is used in many applications like information retrieval, image processing and social network analytics etc. It helps the user to understand the similarity and dissimilarity between objects. Cluster analysis makes the users understand complex and large data sets more clearly. There are different types of clustering algorithms analyzed by various researchers. Kmeans is the most popular partitioning based algorithm as it provides good results because of accurate calculation on numerical data. But Kmeans give good results for numerical data only. Big data is combination of numerical and categorical data. Kprototype algorithm is used to deal with numerical as well as categorical data. Kprototype combines the distance calculated from numeric and categorical data. With the growth of data due to social networking websites, business transactions, scientific calculation etc., there is vast collection of structured, semi-structured and unstructured data. So, there is need of optimization of Kprototype so that these varieties of data can be analyzed efficiently.In this work, Kprototype algorithm is implemented on MapReduce in this paper. Experiments have proved that Kprototype implemented on Mapreduce gives better performance gain on multiple nodes as compared to single node. CPU execution time and speedup are used as evaluation metrics for comparison.Intellegent splitter is proposed in this paper which splits mixed big data into numerical and categorical data. Comparison with traditional algorithms proves that proposed algorithm works better for large scale of data

    BLUE GREEN DEPLOYMENT STRATEGY FOR APPLICATIONS USING KAFKA

    Get PDF
    BLUE GREEN DEPLOYMENT STRATEGY FOR APPLICATIONS USING KAFKA Disclosed herein is a blue-green deployment strategy for consumer applications using the Kafka system. The present disclosure proposes setting producer and consumer configurations in a way that green application consumers are able to consume messages from Kafka topic, hence enabling application teams to test their changes in a green environment. To achieve this, the present disclosure provides a rebalancing of partitions technique where the number of partitions are configured either twice the number of consumers or greater than twice the number of consumers so that all consumers in a consumer group are active and are able to consume data from Kafka topic

    SYSTEM AND METHOD FOR MANAGING FAULTS IN A DISTRIBUTED ENVIRONMENT

    Get PDF
    The present disclosure discloses a method and a system for managing faults in a distributed environment 102. In the present disclosure, the method includes monitoring health metrics of systems 106 in the distributed environment 102. Further, the method includes detecting faults associated with the systems 106 in the distributed environment 102 by identifying abnormal patterns based on monitored data. Furthermore, the method includes reconfiguring the distributed environment 102 to maintain system resilience and performance based on fault detection. Further, the method includes determining a recovery action based on severity of faults. Furthermore, the method includes analyzing and diagnosing issues by logging and auditing the faults

    Incident Management Using Lightning Connect To Connect External Databases

    Get PDF
    Salesforce Lightning concept is used to create powerful, engaging applications with drag-and drop components for everything from standard fields, reports and charts, to partner-built components from App Exchange marketplace, to your own custom designs. Incident management describes the activities of an organization to identify, analyze and correct hazards to prevent a future re-occurrence. Lightning Connect is used for managing incidents and let’s seamlessly access data from external sources, side-by-side with the Salesforce data. We can also pull data from legacy systems such as SAP, Microsoft and Oracle in real time, without making a copy of the data in Salesforce. And it is all easily configured by a simple yet powerful point and click interface

    Stacking Order Driven Optical Properties and Carrier Dynamics in ReS2

    Get PDF
    Two distinct stacking orders in ReS2 are identified without ambiguity and their influence on vibrational, optical properties and carrier dynamics are investigated. With atomic resolution scanning transmission electron microscopy (STEM), two stacking orders are determined as AA stacking with negligible displacement across layers, and AB stacking with about a one-unit cell displacement along the a axis. First-principle calculations confirm that these two stacking orders correspond to two local energy minima. Raman spectra inform a consistent difference of modes I & III, about 13 cm-1 for AA stacking, and 20 cm-1 for AB stacking, making a simple tool for determining the stacking orders in ReS2. Polarized photoluminescence (PL) reveals that AB stacking possesses blue-shifted PL peak positions, and broader peak widths, compared with AA stacking, indicating stronger interlayer interaction. Transient transmission measured with femtosecond pump probe spectroscopy suggests exciton dynamics being more anisotropic in AB stacking, where excited state absorption related to Exc. III mode disappears when probe polarization aligns perpendicular to b axis. Our findings underscore the stacking-order driven optical properties and carrier dynamics of ReS2, mediate many seemingly contradictory results in literature, and open up an opportunity to engineer electronic devices with new functionalities by manipulating the stacking order

    Interobserver and Intraobserver Reliability of Cephalometric Measurements Performed on Smartphone-Based Application and Computer-Based Imaging Software: A Comparative Study

    Get PDF
    Objective:The aim was to compare the reliability of cephalometric analysis using a smartphone-based application with conventional computer-based imaging software.Methods:Pre-treatment cephalometric radiographs of 50 subjects (26 males, 24 females; mean age, 19.2 years; ±4.2) were traced using the OneCeph® application and Dolphin imaging software®. Two independent observers identified seventeen landmarks and measured fourteen cephalometric measurements at an interval of. Interobserver and intraobserver reliability were evaluated using the intraclass correlation coefficient. Student’s t-test was used to compare the means of two measurement methods for observer 1 and observer 2. Additionally, the time taken to complete the cephalometric measurements was also compared between the two methods.Results:Good (ICC 0.75-0.90) to excellent (ICC 0.90-1.00) interobserver and intraobserver reliability was observed for all hard and soft tissue measurements with both methods. No significant differences were found between the two measurement methods for both observers (p<0.05). OneCeph application took significantly more time to complete the analysis than Dolphin imaging software (p<0.001).Conclusion:Cephalometric measurements made through a smartphone-based application showed good to excellent interobserver and intraobserver reliability and are comparable with the computer-based software. Therefore, it can be recommended for clinical use. The time taken to complete the cephalometric measurements was more with a smartphone-based application (OneCeph application) compared to computer-based software (Dolphin imaging software)

    Optical Genome Mapping for the Molecular Diagnosis of Facioscapulohumeral Muscular Dystrophy: Advancement and Challenges

    Get PDF
    Facioscapulohumeral muscular dystrophy (FSHD) is the second most common muscular dystrophy in adults, and it is associated with local D4Z4 chromatin relaxation, mostly via the contraction of the D4Z4 macrosatellite repeat array on chromosome 4q35. In this study, we aimed to investigate the use of Optical Genome Mapping (OGM) as a diagnostic tool for testing FSHD cases from the UK and India and to compare OGM performance with that of traditional techniques such as linear gel (LGE) and Pulsed-field gel electrophoresis (PFGE) Southern blotting (SB). A total of 6 confirmed and 19 suspected FSHD samples were processed with LGE and PFGE, respectively. The same samples were run using a Saphyr Genome-Imaging Instrument (1-color), and the data were analysed using custom EnFocus FSHD analysis. OGM was able to confirm the diagnosis of FSHD1 in all FSHD1 cases positive for SB (n = 17), and D4Z4 sizing highly correlated with PFGE-SB (p &lt; 0.001). OGM correctly identified cases with mosaicism for the repeat array contraction (n = 2) and with a duplication of the D4Z4 repeat array. OGM is a promising new technology able to unravel structural variants in the genome and seems to be a valid tool for diagnosing FSHD1

    Neuromuscular disease genetics in under-represented populations: increasing data diversity

    Get PDF
    Neuromuscular diseases (NMDs) affect ∼15 million people globally. In high income settings DNA-based diagnosis has transformed care pathways and led to gene-specific therapies. However, most affected families are in low-to-middle income countries (LMICs) with limited access to DNA-based diagnosis. Most (86%) published genetic data is derived from European ancestry. This marked genetic data inequality hampers understanding of genetic diversity and hinders accurate genetic diagnosis in all income settings. We developed a cloud-based transcontinental partnership to build diverse, deeply-phenotyped and genetically characterized cohorts to improve genetic architecture knowledge, and potentially advance diagnosis and clinical management. We connected 18 centres in Brazil, India, South Africa, Turkey, Zambia, Netherlands and the UK. We co-developed a cloud-based data solution and trained 17 international neurology fellows in clinical genomic data interpretation. Single gene and whole exome data were analysed via a bespoke bioinformatics pipeline and reviewed alongside clinical and phenotypic data in global webinars to inform genetic outcome decisions. We recruited 6001 participants in the first 43 months. Initial genetic analyses ‘solved’ or ‘possibly solved’ ∼56% probands overall. In-depth genetic data review of the four commonest clinical categories (limb girdle muscular dystrophy, inherited peripheral neuropathies, congenital myopathy/muscular dystrophies and Duchenne/Becker muscular dystrophy) delivered a ∼59% ‘solved’ and ∼13% ‘possibly solved’ outcome. Almost 29% of disease causing variants were novel, increasing diverse pathogenic variant knowledge. Unsolved participants represent a new discovery cohort. The dataset provides a large resource from under-represented populations for genetic and translational research. In conclusion, we established a remote transcontinental partnership to assess genetic architecture of NMDs across diverse populations. It supported DNA-based diagnosis, potentially enabling genetic counselling, care pathways and eligibility for gene-specific trials. Similar virtual partnerships could be adopted by other areas of global genomic neurological practice to reduce genetic data inequality and benefit patients globally
    corecore