Sensitivity Study Research Articles

Integrating complexity in population modelling: From matrix to dynamic models

Matrix models are widely used in population ecology studies and are valuable for analysing population dynamics, although they are limited in the use of time-varying parameters. This limitation can be overcome by dynamic models. In this study, we revisit a previously published study on a matrix model of a population of the box jellyfish Carybdea marsupialis (L. 1758) in the Western Mediterranean. A dynamic model integrating the transition matrix of the original model is developed in STELLA Architect with the following improvements: (1) Sensitivity study of the reliability of the methodology for calculating the transition matrix and estimation of the errors of the fitting parameters; (2) Closure of the jellyfish life cycle by adding the polyp stage. This will make it possible to simulate scenarios of ecological interest over several years such as a decline in food supply, jellyfish removal strategies, changes in drift currents and changes in substrate availability for planulae to settle. (3) The inclusion of more biological reality. In particular, a temporal pattern of strobilation is added, which improves the fit of the model to the field data.

Target sensitivity study of density transition-injected electrons in laser wakefield accelerators

While plasma-based accelerators have the potential to positively impact a broad range of research topics, a route to application will only be possible through improved understanding of their stability. We present experimental results of a laser wakefield accelerator in the nonlinear regime in a helium gas jet target with a density transition produced by a razor blade in the flow. Modifications to the target setup are correlated with variations in the plasma density profile diagnosed via interferometry and the shot-to-shot variations of the density profile for nominally equal conditions are characterized. Through an in-depth sensitivity study using particle-in-cell simulations, the effects of changes in the plasma density profile on the accelerated electron beams are investigated. The results suggest that blade motion is more detrimental to stability than gas pressure fluctuations, and that early focusing of the laser may reduce the deleterious effects of such density fluctuations. Published by the American Physical Society 2024

Triboplasma assisted chemical conversion in granular systems: a semi-analytic model

Abstract We present a semi-analytic model for a novel plasma-assisted chemical conversion pathway using triboplasmas generated in granular flows. Triboelectric charge relaxation is a well known phenomena where the potential generated from contact charging of particles exceeds the breakdown voltage of the background gas. In this work, we extend the triboelectric charge relaxation theory to include non equilibrium plasma energy and particle balance equations to predict the formation of dissociated and excited species that act as precursors to chemical conversion, for example in plasma-assisted ammonia synthesis. 
Our example case study with nitrogen background gas and Teflon/aluminum tribomaterial system yielded high excited nitrogen species densities per collision that are comparable to current plasma-assisted conversion pathways. We also present a regime diagram for various gases where Paschen breakdown parameters are used to determine whether triboplasmas can be formed for a given effective work-function difference between two materials. Our sensitivity studies indicate particle velocity, particle radius, solids fraction and space charge effects play a critical role in overall plasma densities and excited species production.

Results of the experimental study of the antimicrobial activity of therapeutic waters from various wells managed by the federation of trade unions of Uzbekistan

Introduction. Currently, in addition to the traditional use of mineral waters (MW) for the treatment of gastrointestinal tract and renal diseases, they are also used to correct metabolic disorders, normalize lipid and carbohydrate metabolism. However, many of its properties remain poorly studied, and there is a very limited number of works in the scientific literature concerning the analysis of their antibacterial action. Aim. Study of sensitivity of common microorganisms to the action of some MW. Materials and methods. The following test samples from different wells (DW) served as materials for determining the antimicrobial activity of mineral waters: Sample 1. Sodium bicarbonate weakly alkaline mineral water from SW No. 7 (Chinobod Sanatorium, Tashkent); Sample 2. Radon mineral water mineral water from SW No. 2 (Abu Ali ibn Sino Sanatorium, Samarkand Region); Sample 3. Iodine-bromine mineral water from SW No. 4 (Chartak Sanatorium, Namangan Region); Sample 4. Sulfate-sulfur mineral water from SW No. 14 (Chimen Sanatorium, Fergana Region); Sample 5. Concentrated iodine-bromine brine from SCW No. 2 (Chartak Sanatorium, Namangan Region). Results and discussion. Sample No. 5 (concentrated brine) showed antimicrobial activity against Staphylococcus aureus and Pseudomonas aeruginosa, the diameter of the growth inhibition zone was 22 ± 0.26 and 18 ± 0.35 mm, respectively. Also, sample No. 4 (Sanatorium Chimen DW No = 14, sulfate-sulfur mineral water) showed antimicrobial activity against Staphylococcus aureus, the diameter of the growth inhibition zone was 16 ± 0.11 mm. The samples did not show antimicrobial activity against the other test cultures. The antimicrobial action of water samples was determined by the agar diffusion method against some types of opportunistic bacteria: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis and the yeast fungus Candida albicans. All microorganism cultures were obtained from the collection of the Institute of Microbiology of the Academy of Sciences of the Republic of Uzbekistan. The determination was achieved through the use of the agar diffusion method on a dense nutrient medium. Conclusion. It was found that sample No. 5 concentrated brine «Iodine-shifo» from the Chartak Sanatorium showed antimicrobial activity against Staphylococcus aureus and Pseudomonas aeruginosa, i. e. Staphylococcus aureus and Pseudomonas aeruginosa, the diameter of the growth inhibition zone was 22 ± 0.26 and 18 ± 0.35 mm, respectively. Also, sample No. 4 sulfate-sulfur mineral water from the Chimen Sanatorium showed antimicrobial activity against Staphylococcus aureus, the diameter of the growth inhibition zone was 16 ± 0.11 mm. The samples did not show antimicrobial activity against the other test cultures.

A Design Methodology Incorporating a Sound Insulation Prediction Model, Life Cycle Assessment (LCA), and Thermal Insulation: A Comparative Study of Various Cross-Laminated Timber (CLT) and Ribbed CLT-Based Floor Assemblies

Mass timber is increasingly being employed in constructing low- and mid-rise buildings. One of the primary reasons for using mass timber structures is their sustainability and ability to reduce environmental consequences in the building sector. One criticism of these structures is their lower subjective sound insulation quality. Therefore, acoustic treatments should be considered. However, acoustic solutions do not necessarily contribute to lower environmental impacts or improved thermal insulation performance. This paper discusses a design methodology that incorporates the development of a sound insulation prediction tool (using an artificial neural networks approach), life cycle assessment analysis, and thermal insulation study. A total of 112 sound insulation measurements (in one-third octave bands from 50 to 5000 Hz) are utilized to develop the network model and are also used for the LCA and thermal insulation study. They are lab-based measurements and are performed on 45 various CLT- and ribbed CLT-based assemblies. The acoustic model demonstrates satisfactory results with 1 dB differences in the prediction of airborne and impact sound indices (Rw and Ln,w). An acoustic sensitivity study and a statistical analysis are then conducted to validate the model’s results. Additionally, an LCA analysis is performed on the floor assemblies to calculate their environmental footprints. LCA categories are plotted against the acoustic performance of floors. No correlations are found, and the results emphasize that a wide range of sound insulation can be achieved with similar environmental impacts. Within each acoustic performance tier, the LCA results can be optimized for a floor assembly by selecting appropriate materials. The thermal insulation of floors is then calculated. Overall, a strong positive correlation is found between the total thermal resistance and heat loss against acoustic performance. Designers should be cognizant of the trade-offs between acoustic, thermal insulation, and environmental performance when choosing assemblies with favorable environmental impacts relative to acoustic and thermal insulation ratios.

Study of Antibiotic Sensitivity of Pseudomonas aeruginosa Isolated from Women with Urinary Tract Infection

Study of Antibiotic Sensitivity of Pseudomonas aeruginosa Isolated from Women with Urinary Tract Infection

Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of the Neonatal Fc Receptor Inhibitor Rozanolixizumab: An Ethnic Sensitivity Study in Healthy Japanese, Chinese, and White Participants.

Rozanolixizumab is an anti-human neonatal Fc receptor humanized immunoglobulin (Ig) G4 monoclonal antibody that reduces IgG, including pathogenic IgG autoantibodies. Rozanolixizumab safety and tolerability have been assessed in previous clinical studies with predominantly White participants. We assessed safety, tolerability, pharmacokinetics, and pharmacodynamics of single doses of rozanolixizumab in healthy Japanese and Chinese participants compared with White participants. This double-blind, single-center, UK-based, Phase 1 study randomized 65 participants to rozanolixizumab 4mg/kg (Japanese and White participants only), 7 mg/kg, or 10mg/kg. All treatment-emergent adverse events (TEAEs) were mild to moderate in severity; no severe TEAEs, serious TEAEs, or TEAEs leading to discontinuation occurred. Incidences of TEAEs in Japanese and Chinese participants were comparable to those in White participants. Japanese and Chinese participants had lower systemic rozanolixizumab exposure relative to Caucasian participants, attributable to lower actual doses administered due to lower body weight in Chinese and Japanese participants, indicating that body weight is not a relevant predictor of rozanolixizumab pharmacokinetics. All 3 ethnicities demonstrated dose-dependent IgG reductions, with IgG nadir achieved around Day 10 and gradual return to baseline levels by Day 56. These data support the applicability of safety data from previous clinical studies of rozanolixizumab to individuals of Japanese and Chinese ethnicity.

Exploring Mirror Perspectives Among African American Women Living With Obesity at a Primary Care Clinic in the United States.

To uncover the mirror-viewing experience in African-American (AA) women with obesity. Obesity is among the most preventable healthcare epidemics and is linked to multiple health problems. Unfortunately, AA women are disproportionately affected by obesity. Mirror exposure has exclusively used mirrors to treat various eating disorders such as anorexia nervosa, bulimia nervosa and binge eating. Participants in prior mirror exposure studies reported increased self-esteem, body image acceptance, behaviour modification, decreased weight and body shape concerns and lower rates of depression. This qualitative study used hermeneutic phenomenology to explore and methodically analyse participants' experiences. Thirteen AA women who self-identified as having obesity were interviewed. A phenomenological hermeneutical approach was used to explore their mirror-viewing experience. Two environmental themes surrounding this phenomenon were (1) family and culture and (2) stereotype/stigma and bias. Five phenomenological themes were identified: (1) I do not like what I see, (2) the struggle is real, (3) camouflage, (4) call for action and (5) loving the skin you are in. African-American women grappling with obesity confront emotional and body image challenges compounded by family, culture, bias and a sense of alienation within society. The mirror, for many, is an everyday tool that becomes a call for action. Despite earnest attempts to pursue a healthier weight, many find it daunting. Additional investigation into sensitive mirror intervention studies specific to this demographic is warranted to address these multifaceted issues better. The knowledge gained from the study offers an understanding of the mirror-viewing experience in AA women with obesity. Standards for Reporting Qualitative Research. No patient or public contribution.

“Come as you are”: Reconsidering the need for complex quality control when gridding crowd‐sourced weather data

AbstractRecording hourly‐mean in situ observations of surface air temperature is a core task of most National Meteorological and Hydrological Services (NMHSs). Now, suppose that a user is looking for a best estimate of past or present air temperature at a user‐specified location. Can crowd‐sourced weather data help a NMHS to serve this need? In this work, we provide a quantitative answer to this question by computing the cross‐validation root‐mean‐squared error for 1704 individual time slices of observed air‐temperature data in the Netherlands over the year 2023. We consider two baseline services: (i) providing station data as a basis for nearest‐neighbour approximation, a service widely used in legal disputes, insurance claim evaluations, etc., and (ii) providing a gridded dataset, a technically more advanced current service. Our results indicate that service (i) is not expected to be improved by including crowd‐sourced data—for example, the observed relative success rate is 14%—while service (ii) is expected to be improved by multi‐fidelity blending with crowd‐sourced data—for example, the observed relative success rate is 91%. Furthermore, our observations indicate that state‐of‐the‐art, well‐tuned quality control of the crowd‐sourced data (i.e., removing 85% of the data) can—in some of the metrics—lead to improvements of the expected performance of service (i), but—in all metrics—degrades the expected performance of service (ii) significantly. We then continue with a sensitivity study of 96 individual time slices of synthetic air‐temperature data to further understand and nuance these conclusions. Zooming out to the larger perspective, when considering the need for quality control, our results indicate that, for service (i), fewer crowd‐sourced data is better, while, for service (ii), more crowd‐sourced data is better.

Modelling indoor airborne transmission combining architectural design and people movement using the VIRIS simulator and web app

A Viral Infection Risk Indoor Simulator (VIRIS) has been developed to quickly assess and compare mitigations for airborne disease spread. This agent-based simulator combines people movement in an indoor space, viral transmission modelling and detailed architectural design, and it is powered by topologicpy, an open-source Python library. VIRIS generates very fast predictions of the viral concentration and the spatiotemporal infection risk for individuals as they move through a given space. The simulator is validated with data from a courtroom superspreader event. A sensitivity study for unknown parameter values is also performed. We compare several non-pharmaceutical interventions (NPIs) issued in UK government guidance, for two indoor settings: a care home and a supermarket. Additionally, we have developed the user-friendly VIRIS web app that allows quick exploration of diverse scenarios of interest and visualisation, allowing policymakers, architects and space managers to easily design or assess infection risk in an indoor space.

Identifying putative allergens from Cenostigma pluviosum pollen using proteomic bioinformatics.

Routinely, signs and symptoms of pollinosis worsen during the flowering period of the Cenostigma pluviosum var. peltophoroides (Sibipiruna) trees. This study aimed to determine whether Sibipiruna pollen contains allergenic proteins. The pollen from mature Sibipiruna anthers was morphologically characterized using optical, scanning electron and emission microscopy. Additionally, biochemical characterization was conducted through Shotgun Label-Free Proteomic Analysis. Three hundred and forty-nine proteins were identified using the UNIPROT database and thirty-six were confirmed as homologous allergenic proteins in the Allergome database. At the first time, Sibipiruna pollen allergenic proteins have been described and this study provides a deeper understanding of the allergenic proteins present in this pollen. These preliminary findings can be useful to assist in the development of targeted extracts for the study of sensitization and potential immunotherapy in the future.

A Study of Loss Model Parameter Sensitivity in Compressor Unsteady Flow Simulations

Abstract This article presents results from a comprehensive sensitivity analysis focused on loss models used in a recently developed compressor unsteady mean line flow model for a transonic axial-centrifugal compressor. The mean line flow model treats flow through rotors and stators in their respective reference frames (rotating or stationary), and the compressor performance is determined by the kinetic energy addition and various physics-based loss models in relative frames. In this paper, we describe the modeling approach of the compressor flow model, as well as the loss models that are used to obtain a relatively good match against test data. Sensitivity studies of selected loss model parameters are presented to show the effect of individual loss model parameters on the overall compressor characteristics in the entire speed range. The effects of losses on unsteady flow transients are assessed by comparing the transient responses when a step reduction of throttle area is applied. The comparisons show that the change in loss magnitude has weak effects on transient response if the change of loss does not significantly change the system stability.

The impact of cloud microphysics and ice nucleation on Southern Ocean clouds assessed with single-column modeling and instrument simulators

Abstract. Supercooled liquid clouds are common at higher latitudes (especially over the Southern Ocean) and are critical for constraining climate projections. We take advantage of the Macquarie Island Cloud and Radiation Experiment (MICRE) to perform an analysis of observed and simulated cloud processes over the Southern Ocean in a region and season dominated by supercooled liquid clouds. Using a single-column version of the European Centre for Medium-Range Weather Forecasts (ECMWF) Integrated Forecast System (IFS), we compare two different cloud microphysical schemes to ground-based observations of cloud, precipitation, and radiation over a 2.5-month period (1 January–17 March 2017). Both schemes are able to reproduce aspects of the cloud and radiation observations during MICRE to within the uncertainty of the data when the thermodynamic profile is prescribed with relaxation. There are differences in water mass and representation of reflectivity between the schemes. A sensitivity study of the cloud microphysics schemes, one a bulk one-moment scheme and the other a two-moment scheme with prediction of mass and number, indicates that several key processes create differences between the schemes. Surface radiative fluxes and total water path are highly sensitive to the formation and fall speed of precipitation. The prediction of hydrometeor number with the two-moment scheme yields a better comparison with observed reflectivity and radiative fluxes, despite predicting higher liquid water contents than observed. With the two-moment scheme, we are also able to test the sensitivity of the results to the input of liquid cloud condensation nuclei (CCN) and ice nuclei (IN). The cloud properties and resulting radiative effects are found to be sensitive to the CCN and IN concentrations. More CCN and IN increase liquid and ice water paths, respectively. Thus, both the dynamic environment and aerosols, integrated through the cloud microphysics, are important for properly representing Southern Ocean cloud radiative effects.

A Phase 2 Sensitivity and Selectivity Study of High-Dose 5-Aminolevulinic Acid in Adult Patients Undergoing Resection of a Newly Diagnosed or Recurrent Glioblastoma.

The utility of oral 5-aminolevulinic acid (5-ALA)/protoporphyrin fluorescence for the resection of high-grade gliomas is well documented, but the problem of false-negative observations remains. This study compares high-grade glioma visualization with low/standard dose 5-ALA (<30 mg/kg) to high-dose 5-ALA (>40 mg/kg) to see if by using this higher dose, it is possible to reduce the rate of false-negative observations without increasing the rate of false-positive (FP) observations and therefore increase the sensitivity. This is a prospective study of consecutive patients with radiological evidence of presumed high-grade glioma. We reviewed the data from patients who received preoperative low/standard doses and patients who received a preoperative high dose of 5-ALA. Adverse events, dose to observation time, intensity of tumor fluorescence, and results of biopsies in areas of tumor and tumor bed under deep blue light were recorded. A total of 22 patients with high-grade glioma received a dose >40 mg/kg (high-dose) and 9 patients received <30 mg/kg (low/standard dose). There were no serious adverse events related to 5-ALA in any subject. There was a very high sensitivity and specificity of 5-ALA for the presence of tumor in both groups. There were no FP observations (fluorescence with no tumor) in either group. The specificity and the positive predictive value were 100% in both groups. The sensitivity and the negative predictive value were 53.3% and 30.0% in the low/standard dose group and 59.5% and 31.8% in the high-dose group, respectively. High-dose oral 5-aminolevulinic/protoporphyrin fluorescence is a safe and effective aid to the intraoperative detection of high-grade gliomas with high sensitivity and specificity. False-negative observations with a high dose do not seem to be less than that with a low/standard dose. The rate of FP observations with both groups remains very low.

4E analysis and optimization comparison of solar, biomass, geothermal, and wind power systems for green hydrogen-fueled SOFCs

Integrating renewable energies with hydrogen production via electrolysis and utilizing hydrogen as a fuel for solid oxide fuel cells (SOFCs) presents a synergistic approach towards sustainable energy generation. This coupling offers enhanced flexibility, allowing for efficient energy storage and distribution, thereby addressing intermittency issues associated with renewable sources. Additionally, the utilization of hydrogen in SOFCs enables high-efficiency power generation with reduced emissions, contributing to the transition towards a cleaner energy landscape. In the present study, four types of renewable energies, namely solar, biomass, geothermal, and wind, produce hydrogen by coupling power generation units and a proton exchange membrane electrolyzer (PEME). Then, the produced hydrogen is stored and used for later utilization in an SOFC subsystem. A 4E (energy, exergy, exergy-economic, and environmental) study is conducted for the proposed systems through a sensitivity study and design optimization. In the best output performance mode, the best exergy efficiency is obtained by the biomass-based system, which is equal to 9.40 %, and the lowest values for total cost rate and unit cost of outputs are achievable by the geothermal-based system, with values of 27.72 $/h and 43.23 $/GJ.

A Sensitive Frequency Band Study for Distributed Acoustical Sensing Monitoring Based on the Coupled Simulation of Gas–Liquid Two-Phase Flow and Acoustic Processes

The sensitivity of gas and water phases to DAS acoustic frequency bands can be used to interpret the production profile of horizontal wells. DAS typically collects acoustic signals in the kilohertz range, presenting a key challenge in identifying the sensitive frequency bands of the gas and water phases in the production well for accurate interpretation. In this study, a gas–water two-phase flow–acoustic coupling model for a horizontal well is developed by integrating a gas–water separation flow model with a pipeline acoustic model. The model simulates the sound pressure level (SPL) and amplitude variations of acoustic waves under different flow patterns, spatial locations, and gas–water ratio schemes. The results demonstrate that within the same flow pattern, an increase in the gas–water ratio significantly elevates acoustic amplitude and SPL peaks within the 5–50 Hz frequency band. Analysis of oil field DAS data reveals that the amplitude response range for stages with a lower gas–water ratio falls within 5–10 Hz, whereas stages with a higher gas–water ratio exhibit an amplitude response range of 10–50 Hz.

Generation of 10 kT axial magnetic fields using multiple conventional laser beams: A sensitivity study for kJ PW-class laser facilities

Strong multi-kilotesla magnetic fields have various applications in high-energy density science and laboratory astrophysics, but they are not readily available. In our previous work [Y. Shi et al., Phys. Rev. Lett. 130, 155101 (2023)], we developed a novel approach for generating such fields using multiple conventional laser beams with a twist in the pointing direction. This method is particularly well-suited for multi-kilojoule petawatt-class laser systems like SG-II UP, which are designed with multiple linearly polarized beamlets. Utilizing three-dimensional kinetic particle-in-cell simulations, we examine critical factors for a proof-of-principle experiment, such as laser polarization, relative pulse delay, phase offset, pointing stability, and target configuration, and their impact on magnetic field generation. Our general conclusion is that the approach is very robust and can be realized under a wide range of laser parameters and plasma conditions. We also provide an in-depth analysis of the axial magnetic field configuration, azimuthal electron current, and electron and ion orbital angular momentum densities. Supported by a simple model, our analysis shows that the axial magnetic field decays owing to the expansion of hot electrons.

A fully coupled solid-particle microphysics scheme for stratospheric aerosol injections within the aerosol–chemistry–climate model SOCOL-AERv2

Abstract. Recent studies have suggested that injection of solid particles such as alumina and calcite particles for stratospheric aerosol injection (SAI) instead of sulfur-based injections could reduce some of the adverse side effects of SAI such as ozone depletion and stratospheric heating. Here, we present a version of the global aerosol–chemistry–climate model SOCOL-AERv2 and the Earth system model (ESM) SOCOLv4 which incorporate a solid-particle microphysics scheme for assessment of SAI of solid particles. Microphysical interactions of the solid particle with the stratospheric sulfur cycle were interactively coupled to the heterogeneous chemistry scheme and the radiative transfer code (RTC) for the first time within an ESM. Therefore, the model allows simulation of heterogeneous chemistry at the particle surface as well as feedbacks between microphysics, chemistry, radiation and climate. We show that sulfur-based SAI results in a doubling of the stratospheric aerosol burden compared to the same mass injection rate of calcite and alumina particles with a radius of 240 nm. Most of the sulfuric acid aerosol mass resulting from SO2 injection does not need to be lifted to the stratosphere but is formed after in situ oxidation and subsequent water uptake in the stratosphere. Therefore, to achieve the same radiative forcing, larger injection rates are needed for calcite and alumina particle injection than for sulfur-based SAI. The stratospheric sulfur cycle would be significantly perturbed, with a reduction in stratospheric sulfuric acid burden by 53 %, when injecting 5 Mt yr−1 (megatons per year) of alumina or calcite particles of 240 nm radius. We show that alumina particles will acquire a sulfuric acid coating equivalent to about 10 nm thickness if the sulfuric acid is equally distributed over the whole available particle surface area in the lower stratosphere. However, due to the steep contact angle of sulfuric acid on alumina particles, the sulfuric acid coating would likely not cover the entire alumina surface, which would result in available surface for heterogeneous reactions other than the ones on sulfuric acid. When applying realistic uptake coefficients of 1.0, 10−5 and 10−4 for H2SO4, HCl and HNO3, respectively, the same scenario with injections of calcite particles results in 94 % of the particle mass remaining in the form of CaCO3. This likely keeps the optical properties of the calcite particles intact but could significantly alter the heterogeneous reactions occurring on the particle surfaces. The major process uncertainties of solid-particle SAI are (1) the solid-particle microphysics in the injection plume and degree of agglomeration of solid particles on the sub-ESM grid scale, (2) the scattering properties of the resulting agglomerates, (3) heterogeneous chemistry on the particle surface, and (4) aerosol–cloud interactions. These uncertainties can only be addressed with extensive, coordinated experimental and modelling research efforts. The model presented in this work offers a useful tool for sensitivity studies and incorporating new experimental results on SAI of solid particles.

A time-relaxation reduced order model for the turbulent channel flow

Regularized reduced order models (Reg-ROMs) are stabilization strategies that leverage spatial filtering to alleviate the spurious numerical oscillations generally displayed by the classical Galerkin ROM (G-ROM) in under-resolved numerical simulations of turbulent flows. In this paper, we propose a new Reg-ROM, the time-relaxation ROM (TR-ROM), which filters the marginally resolved scales. We compare the new TR-ROM with the two other Reg-ROMs in current use, i.e., the Leray ROM (L-ROM) and the evolve-filter-relax ROM (EFR-ROM) and one eddy viscosity model, the mixing-length model, in the numerical simulation of the turbulent channel flow at Reτ=180 and Reτ=395 in both the reproduction and the predictive regimes. For each Reg-ROM, we investigate two different filters: (i) the differential filter (DF), and (ii) the higher-order algebraic filter (HOAF). In our numerical investigation, we monitor the Reg-ROM performance with respect to the ROM dimension, N, and the filter order. We also perform sensitivity studies of the three Reg-ROMs with respect to the time interval, relaxation parameter, and filter radius. The numerical results yield the following conclusions: (i) All three Reg-ROMs are significantly more accurate than the G-ROM. (ii) All three Reg-ROMs are more accurate than the ROM projection in terms of Reynolds stresses. (iii) With the optimal parameter values, the new TR-ROM yields more accurate results than the L-ROM and the EFR-ROM in all tests. (iv) The new TR-ROM is more accurate than the mixing-length ROM. (v) For most N values, DF yields the most accurate results for all three Reg-ROMs. (vi) The optimal parameters trained in the reproduction regime are also optimal for the predictive regime for most N values, demonstrating the Reg-ROM predictive capabilities. (vii) All three Reg-ROMs are sensitive to the filter order and the filter radius, and the EFR-ROM and the TR-ROM are sensitive to the relaxation parameter. (viii) The optimal range for the filter radius and the effect of relaxation parameter are similar for the two Reτ values.

Study of Etiopathological Factors, Clinical Parameters and Culture Sensitivity of Patients Suffering from Diabetic Foot Ulcer

Study of Etiopathological Factors, Clinical Parameters and Culture Sensitivity of Patients Suffering from Diabetic Foot Ulcer