33 research outputs found

    Search for Gravitational Waves from Core Collapse Supernovae in Ligo\u27s Observation Runs Using a Network of Detectors

    Get PDF
    Core-Collapse Supernova (CCSN) is one of the most anticipated sources of Gravitational Waves (GW) in the fourth observation run (O4) of LIGO and other network of GW detectors. A very low rate of galactic CCSN, coupled with the fact that the CCSN waveforms are unmodeled, make detection of these signals extremely challenging. Mukherjee et. al. have developed a new burst search pipeline, the Multi-Layer Signal Enhancement with cWB and CNN or MuLaSEcC, that integrates a non-parametric signal estimation and Machine Learning. MuLaSEcC operates on GW data from a network of detectors and enhances the detection probability while reducing the false alarm significantly. The aim of this research is to analyze the detection probability of CCSN during O4 and how well the signals may be reconstructed for parameter estimation. CCSN waveforms are generated in supercomputers by the implementation of complex physics. The CCSN GW waveforms used in this analysis correspond to various explosion scenarios. These are Powell and Muller s18, Scheidegger R3E1AC_L, Ott 2013_s27_fheat1d00, Mezzacappa 2020_c15_3D, Morozova 2018_M13_SFHo_multipole, Andresen 2019 s15fr, Kuroda 2016_TM1, Kuroda 2017 s11.2 and Richers 2017 A300w0_50_HSDD2. The study has demonstrated improved result in terms of reduction in the false alarm rate and broadband reconstruction of the detected signals. Efficiency of the pipeline as a function of distance has been seen to be sensitive up to the galactic range. Receiver operating characteristics have been generated to demonstrate the performance of the pipeline in comparison to other standard operating pipelines within the GW community

    O gravitomagnetskom satnom č

    Get PDF
    We show that the whole of the gravitomagnetic clock effect in the orbit of a spinning test particle which is revolving round a spinning central massive astrophysical body can be calculated using a gravitational spin-orbit coupling potential which involves the two spins and the orbital angular momentum of the test particle.Pokazujemo da se ukupni gravitomagnetski satni učinak za stazu ispitne čestice, koja se vrti i kruži oko središnjeg masivnog astrofizičkog tijela koje se vrti, može izračunati primjenom gravitacijskog potencijala vezanja spina i staze dviju vrtnji i staznog momenta impulsa ispitne čestice

    LogShield: A Transformer-based APT Detection System Leveraging Self-Attention

    Full text link
    Cyber attacks are often identified using system and network logs. There have been significant prior works that utilize provenance graphs and ML techniques to detect attacks, specifically advanced persistent threats, which are very difficult to detect. Lately, there have been studies where transformer-based language models are being used to detect various types of attacks from system logs. However, no such attempts have been made in the case of APTs. In addition, existing state-of-the-art techniques that use system provenance graphs, lack a data processing framework generalized across datasets for optimal performance. For mitigating this limitation as well as exploring the effectiveness of transformer-based language models, this paper proposes LogShield, a framework designed to detect APT attack patterns leveraging the power of self-attention in transformers. We incorporate customized embedding layers to effectively capture the context of event sequences derived from provenance graphs. While acknowledging the computational overhead associated with training transformer networks, our framework surpasses existing LSTM and Language models regarding APT detection. We integrated the model parameters and training procedure from the RoBERTa model and conducted extensive experiments on well-known APT datasets (DARPA OpTC and DARPA TC E3). Our framework achieved superior F1 scores of 98% and 95% on the two datasets respectively, surpassing the F1 scores of 96% and 94% obtained by LSTM models. Our findings suggest that LogShield's performance benefits from larger datasets and demonstrates its potential for generalization across diverse domains. These findings contribute to the advancement of APT attack detection methods and underscore the significance of transformer-based architectures in addressing security challenges in computer systems

    IN-VITRO COMPARATIVE STUDY OF ANTI-INFLAMMATORY AND ANTI-ARTHRITIC EFFECTS OF FLEMINGIA STRICTA ROXB AND NYMPHAEA NOUCHALI LEAF

    Get PDF
    Objective: To evaluate the comparative study of anti-inflammatory, anti-arthritic activity of methanol extract of Flemingia stricta and Nymphaea nouchali leaf.Methods: Human Red Blood Cell (HRBC) membrane stabilization method was evaluated for anti-inflammatory activity. Anti-denaturation method was performed by using Bovine Serum Albumin (BSA) to evaluate the anti-arthritic potential.Results: The in vitro anti-inflammatory activity of the methanol extracts of Flemingia stricta and Nymphaea nouchali showed 81.85±0.67% (P<0.01) and 85.59±0.58% (P<0.01) of membrane stabilization at 1000µg/ml conc. and 51.85±0.49% (P<0.01) and 70.63±0.50% (P<0.01) at 31.25µg/ml respectively. All the results were compared with standard Diclofenac which showed 93.15±1.03% protection at 1000µg/ml conc. The in vitro study on both leaves also showed the presence of significant anti-arthritic activity. Here the extracts showed 70.43±1.42% (P<0.01) and 83.33±0.54% of protein denaturation at the highest conc. (1000 µg/ml) and 39.25±1.08% (P<0.01) and 38.71±0.93% (P<0.01) at the lowest conc. (31.25µg/ml), in where the standard drug displayed the 86.56±2.15% at 1000ug/ml and 51.08±1.42% at 31.25 µg/ml.Conclusion: These results suggest that both the methanol extract of Flemingia stricta and Nymphaea nouchali possess significant anti-inflammatory and anti-arthritic activity.Â

    Assessment of in-vivo anti-diabetic and anti-diarrheal effects of Flemingia stricta Roxb. leaf

    Get PDF
    The objective of this study was to evaluate the anti-diabetic and anti-diarrheal activity of methanol extract of Flemingia stricta Roxb. (Fabaceae) leaf. In anti-diabetic study, the extract was administered to alloxan-induce diabetic mice at two concentrations (200 mg/kg and 400 mg/kg body weight) for acute (12 hours) and prolong treatments (15 days) and blood glucose levels of diabetic mice were monitored at intervals of hours and days throughout the duration of treatment. Antidiarrheal test was conducted by castor oil induced diarrhea and enteropooling as well as intestinal motility in mice at three different concentration (100 mg/kg, 200 mg/kg and 400 mg/kg body weight). Treatment of alloxan induce diabetic mice with the extract caused a significant reduction in fasting blood glucose level of the diabetic mice both in acute (12 hours) and prolong treatment (15 days) and it was determined that the F. stricta methanol extract at both concentration (200 mg/kg and 400 mg/kg) showed the significant (P<0.05) hypoglycemic effect in comparison to the standard drug metformin. In the case of castor oil induced diarrheal test, enteropooling test and gastrointestinal motility test, the extract of F. stricta  at 100 mg/kg, 200 mg/kg and 400 mg/kg has given significant effect (P<0.05) compared to the standard drug loperamide. But 400 mg/kg demonstrated the highest activity amongst the three doses. These results suggested that the methanol extract of F. stricta Roxb. possess promising anti-diabetic effect on alloxan-induced mice and significant antidiarrheal effect on castor oil induced diarrheal mice. DOI: http://dx.doi.org/10.5281/zenodo.383974

    Anti-oxidant effect of Flemingia stricta Roxb. leaves methanolic extract

    Get PDF
    Aim of the study was to evaluate the possible anti-oxidant activity of Flemingia stricta leaf extract. In antioxidant study, plant crude methanol extract was evaluated for 1,1-diphenyl,2-picrylhydrazyl (DPPH) and reducing power capacity. Moreover, total phenolic and total flavonoid content of plant extracts were determined and expressed in mg of gallic acid equivalent per gram of dry sample (mg GAE/g dry weight). In the DPPH free radical scavenging assay, methanol extract showed concentration dependent inhibition of the free radicals. IC50 of ascorbic acid and F. stricta leaves were 4.25 µg/ml and 320.47 µg/ml respectively. In case of reducing capacity, the methanol extract at concentrations of 25, 50, 100, 200, 400 µg/ml, the absorbances were 0.56, 0.92, 1.41, 1.76, 2.23, respectively. Total phenolic content was estimated by gallic acid and expressed as milligrams of gallic acid equivalent (GAE). The methanol extracts contained a considerable amount of phenolic contents of 482±8.72 of GAE/g of extract and the total flavonoid content of the F. stricta leaf was estimated by using aluminium chloride colorimetric technique and found that the extract contained flavonoid content 340.625±4.50 of GAE/g of extract. These results suggested that the methanol extract of F. stricta Roxb. possess anti-oxidant activity. DOI: http://dx.doi.org/10.5281/zenodo.146976

    Alterations In the Transciptome and Antibiotic Susceptibility of \u3ci\u3eStaphylococcus aureus\u3c/i\u3e Grown In the Presence of Diclofenac

    Get PDF
    Background Diclofenac is a non-steroidal anti-inflammatory drug (NSAID) which has been shown to increase the susceptibility of various bacteria to antimicrobials and demonstrated to have broad antimicrobial activity. This study describes transcriptome alterations in S. aureus strain COL grown with diclofenac and characterizes the effects of this NSAID on antibiotic susceptibility in laboratory, clinical and diclofenac reduced-susceptibility (DcRS) S. aureus strains. Methods Transcriptional alterations in response to growth with diclofenac were measured using S. aureus gene expression microarrays and quantitative real-time PCR. Antimicrobial susceptibility was determined by agar diffusion MICs and gradient plate analysis. Ciprofloxacin accumulation was measured by fluorescence spectrophotometry. Results Growth of S. aureus strain COL with 80 μg/ml (0.2 × MIC) of diclofenac resulted in the significant alteration by ≥2-fold of 458 genes. These represented genes encoding proteins for transport and binding, protein and DNA synthesis, and the cell envelope. Notable alterations included the strong down-regulation of antimicrobial efflux pumps including mepRAB and a putative emrAB/qacA-family pump. Diclofenac up-regulated sigB (σB), encoding an alternative sigma factor which has been shown to be important for antimicrobial resistance. Staphylococcus aureus microarray metadatabase (SAMMD) analysis further revealed that 46% of genes differentially-expressed with diclofenac are also σB-regulated. Diclofenac altered S. aureus susceptibility to multiple antibiotics in a strain-dependent manner. Susceptibility increased for ciprofloxacin, ofloxacin and norfloxacin, decreased for oxacillin and vancomycin, and did not change for tetracycline or chloramphenicol. Mutation to DcRS did not affect susceptibility to the above antibiotics. Reduced ciprofloxacin MICs with diclofenac in strain BB255, were not associated with increased drug accumulation. Conclusions The results of this study suggest that diclofenac influences antibiotic susceptibility in S. aureus, in part, by altering the expression of regulatory and structural genes associated with cell wall biosynthesis/turnover and transport

    Alterations in the transcriptome and antibiotic susceptibility of Staphylococcus aureus grown in the presence of diclofenac

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Diclofenac is a non-steroidal anti-inflammatory drug (NSAID) which has been shown to increase the susceptibility of various bacteria to antimicrobials and demonstrated to have broad antimicrobial activity. This study describes transcriptome alterations in <it>S. aureus </it>strain COL grown with diclofenac and characterizes the effects of this NSAID on antibiotic susceptibility in laboratory, clinical and diclofenac reduced-susceptibility (Dc<sup>RS</sup>) <it>S. aureus </it>strains.</p> <p>Methods</p> <p>Transcriptional alterations in response to growth with diclofenac were measured using <it>S. aureus </it>gene expression microarrays and quantitative real-time PCR. Antimicrobial susceptibility was determined by agar diffusion MICs and gradient plate analysis. Ciprofloxacin accumulation was measured by fluorescence spectrophotometry.</p> <p>Results</p> <p>Growth of <it>S. aureus </it>strain COL with 80 μg/ml (0.2 × MIC) of diclofenac resulted in the significant alteration by ≥2-fold of 458 genes. These represented genes encoding proteins for transport and binding, protein and DNA synthesis, and the cell envelope. Notable alterations included the strong down-regulation of antimicrobial efflux pumps including <it>mepRAB </it>and a putative <it>emrAB/qacA</it>-family pump. Diclofenac up-regulated <it>sigB </it>(σ<sup>B</sup>), encoding an alternative sigma factor which has been shown to be important for antimicrobial resistance. <it>Staphylococcus aureus </it>microarray metadatabase (SAMMD) analysis further revealed that 46% of genes differentially-expressed with diclofenac are also σ<sup>B</sup>-regulated. Diclofenac altered <it>S. aureus </it>susceptibility to multiple antibiotics in a strain-dependent manner. Susceptibility increased for ciprofloxacin, ofloxacin and norfloxacin, decreased for oxacillin and vancomycin, and did not change for tetracycline or chloramphenicol. Mutation to Dc<sup>RS </sup>did not affect susceptibility to the above antibiotics. Reduced ciprofloxacin MICs with diclofenac in strain BB255, were not associated with increased drug accumulation.</p> <p>Conclusions</p> <p>The results of this study suggest that diclofenac influences antibiotic susceptibility in <it>S. aureus</it>, in part, by altering the expression of regulatory and structural genes associated with cell wall biosynthesis/turnover and transport.</p
    corecore