24 research outputs found

    PREDICTIVE MODELING USING CAPILLARY PRESSURE MODELS AND FLUID DENSITIES AND THEIR EFFECT ON RESERVOIR FLUID DISTRIBUTION AND DYNAMICS

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    Capillary pressure has always been a point of concern for reservoir modeling. It describes the initial pressure at which the de-saturation will be initiated and at the other extreme; it defines the irreducible saturation of the displaced fluid. In this study, Brooks & Corey and Van Genuchten models are used to predict maximum displacement pressure data with reference to non-uniformity in pore-size distribution. Both models are compared and a correlation has been developed to predict maximum displacement pressure with reference to variation in pore-size distribution index for Van Genuchten model. Further, the fluid distribution and water-oil contact level with reference to free-water level has been calculated using both models for reservoir modeling. The obtained results show that Van Genuchten model gives higher thickness for transition zones and difference in water-oil contact level with reference to free water level, as compared to Brooks and Corey correlation. Furthermore, on comparative basis, these differences increase with the decrease in uniformity in pore size distribution. Thus, the degree of uncertainty and complexity in developing reservoirs and analyzing fluid dynamics increases, in case of tighter or heterogeneous formations. Further, this study also shows that density also plays an important role in fluid dynamics and distribution with the reservoir

    Ubiquitin-specific peptidase 37: an important cog in the oncogenic machinery of cancerous cells.

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    Protein ubiquitination is one of the most crucial posttranslational modifications responsible for regulating the stability and activity of proteins involved in homeostatic cellular function. Inconsistencies in the ubiquitination process may lead to tumorigenesis. Ubiquitin-specific peptidases are attractive therapeutic targets in different cancers and are being evaluated for clinical development. Ubiquitin-specific peptidase 37 (USP37) is one of the least studied members of the USP family. USP37 controls numerous aspects of oncogenesis, including stabilizing many different oncoproteins. Recent work highlights the role of USP37 in stimulating the epithelial-mesenchymal transition and metastasis in lung and breast cancer by stabilizing SNAI1 and stimulating the sonic hedgehog pathway, respectively. Several aspects of USP37 biology in cancer cells are yet unclear and are an active area of research. This review emphasizes the importance of USP37 in cancer and how identifying its molecular targets and signalling networks in various cancer types can help advance cancer therapeutics.This study was supported by AIIMS Intramural grant (Grant number: A514) and AIIMS IITD Grant (AI-34) from All India Institute of Medical Sciences (AIIMS) New Delhi, Delhi India to Mayank singh. Sidra Medicine Precision Program provides research funding to Mohammad Haris (5081012002). Muzafar A. Macha is supported by Ramalingaswami Fellowship (Grant number: D.O. NO.BT/HRD/35/02/2006) from the Department of Biotechnology, Govt. of India, New Delhi

    Tumor associated PD-L1 expression pattern in microscopically tumor positive sentinel lymph nodes in patients with melanoma

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    Background: Characterization of PD-L1 expression within clinically/radiologically negative but microscopically tumor positive sentinel lymph nodes (SLN) is important to our understanding of the relevance of this immune checkpoint pathway for adjuvant therapy. Methods: Patients included had primary cutaneous melanoma, Breslow thickness of 2.01-4.0 or >4mm with or without tumor ulceration (T3a, T3b, T4a, T4b). All patients had microscopically tumor positive SLN. Hematoxylin and eosin (H&E) staining was performed, followed by PD-L1 immunohistochemical (IHC) staining using a preliminary IHC assay with anti-PD-L1 antibody clone 22C3. The slides were separately evaluated by two pathologists (JY and CG). Samples containing metastatic melanoma lesions were scored separately for PD-L1 expression in intratumoral and peritumoral locations, by utilizing two scoring methods. Results: Twenty-four patients where metastatic melanoma presence in the SLN was confirmed by H&E review of the cut sections were included in the final analysis of PD-L1 expression. SLN tumor size ranged from 1 to 2mm. For three patients, the melanin content was too high to confidently assign a PD-L1 score. For the remaining 21 patients, all had some evidence of either intratumoral or peritumoral PD-L1 expression. The frequency of intratumoral tumor-associated PD-L1 expression was: 0% of tumor cells (3pts, 14%); 10% (7pts, 33%). Conclusions: Tumor-associated PD-L1 expression is readily detectable within melanoma micrometastases in the SLN of the majority of patients. These results support the testing of a therapeutic role for PD1/PD-L1 inhibition in the adjuvant setting, targeting melanoma micrometastases

    Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

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    Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

    Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

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    Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

    Ultralight vector dark matter search using data from the KAGRA O3GK run

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    Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

    Investigative coupled thermo-hydro-mechanical modelling approach for geothermal heat extraction through multistage hydraulic fracturing from hot geothermal sedimentary systems

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    The meaningful utilization of artificially created multiple fractures in tight formations is associated with the performance behavior of such flow channels, especially in the case of thermal energy extraction from sedimentary geothermal system. In this study, an innovative idea is presented to develop a numerical model for geothermal energy production based on concrete physical performance of an artificially created tensile multi-fracture system in a simplified manner. The state-of-the-art software FLAC3Dplus-TOUGH2MP-TMVOC are integrated to develop a coupled thermo-hydro-mechanical (THM) fictive model for constructing a multi-fracture scheme and estimating heat extraction performance. By incorporating the actual fracture width of newly created subsequent fracture under the effect of stress shadow, cubic law is implemented for fluid flow and geothermal energy production. The results depict that fracture spacing plays a vital role in the energy contribution through multiple fractures. Afterwards, a field case study to design huge multiple hydraulic fractures was performed in the geothermal well GB X1 in North Germany. The attenuation of fracture propagation becomes more significant when massive multiple fracturing operation is performed especially in the case of lower fracture spacing. The fictive model results will be extended to study the geothermal utilization of the North German basin through massive multiple fractures in our future work

    Recent Advances in the Synthesis, Application and Economic Feasibility of Ionic Liquids and Deep Eutectic Solvents for CO<sub>2</sub> Capture: A Review

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    Global warming is one of the major problems in the developing world, and one of the major causes of global warming is the generation of carbon dioxide (CO2) because of the burning of fossil fuels. Burning fossil fuels to meet the energy demand of households and industries is unavoidable. The current commercial and experimental techniques used for capturing and storing CO2 have serious operational and environmental constraints. The amine-based absorption technique for CO2 capture has a low absorption and desorption ratio, and the volatile and corrosive nature of the solvent further complicates the situation. To overcome all of these problems, researchers have used ionic liquids (ILs) and deep eutectic solvents (DESs) as a replacement for commercial amine-based solvents. ILs and deep eutectic solvents are tunable solvents that have a very low vapor pressure, thus making them an ideal medium for CO2 capture. Moreover, most ionic liquids and deep eutectic solvents have low toxicity and can be recycled without a significant loss in their CO2 capture capability. This paper first gives a brief overview of the ILs and DESs used for CO2 capture, followed by the functionalization of ILs to enhance CO2 capture. Moreover, it provides details on the conversion of CO2 into different valuable products using ILs and DESs, along with an economic perspective on using both of these solvents for CO2 capture. Furthermore, it provides insight into the difficulties and drawbacks that are faced by industries when using ILs and DESs

    Statistical Simulation of the Switching Mechanism in ZnO-Based RRAM Devices

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    Resistive random access memory (RRAM) has two distinct processes, the SET and RESET processes, that control the formation and dissolution of conductive filament, respectively. The laws of thermodynamics state that these processes correspond to the lowest possible level of free energy. In an RRAM device, a high operating voltage causes device degradation, such as bends, cracks, or bubble-like patterns. In this work, we developed a statistical simulation of the switching mechanism in a ZnO-based RRAM. The model used field-driven ion migration and temperature effects to design a ZnO-based RRAM dynamic SET and RESET resistance transition process. We observed that heat transport within the conducting filament generated a great deal of heat energy due to the carrier transport of the constituent dielectric material. The model was implemented using the built-in COMSOL Multiphysics software to address heat transfer, electrostatic, and yield RRAM energy. The heat energy increased with the increase in the operating power. Hence, the reliability of a device with high power consumption cannot be assured. We obtained various carrier heat analyses in 2D images and concluded that developing RRAM devices with low operating currents through material and structure optimization is crucial

    Gram Negative Extended Spectrum Beta-Lactamase Producing Bacteria Prevalence in Jouf Region Tertiary Care Hospital, Saudi Arabia

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    Extended Spectrum beta lactamase producing pathogens are reported in many clinical samples and pose an emerging threat health. To find the prevalence of ESBL producing Enterobactriacea pathogens isolated from inpatients (Medical and Surgical Wards; Hospital stay > 72 h) admitted to Prince, Mutib, Hospital Sakaka, Jouf. A total of 1043 Enterobactriacea were isolated during April 2015 to October 2016 study period. Vitek -2 compact (biomeriux Leon, France) was used for identification and antimicrobial sensitivity (AST) test. A Total of 115/1043 (11.02%) ESBL producing pathogens were isolated from urine 15.07% (n=242), sputum 13.6 % (n=220), wound 10.8% (n=287) and blood 5.4 % (n=294). Klebsiella pneumonia is most dominant followed by E coli and Proteus miribilis. Cephamycins and carbapenems were found most effective (100% sensitivity) against the pathogens isolated. The aminoglycosides, beta lactams and Fluroquinolnes class of antibiotics, microorganisms have gained the resistance of 20%, 22.7%, 40-70% respectively. The infection control measures should be taken seriously and making of effective use of antibiotics is need of hour
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