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Purpose This paper aims to study the magneto-radiative gas (water vapor) on an unsmooth boundary. Design/methodology/approach This paper provided a numerical treatment via the implicit Chebyshev pseudo-spectral method to investigate unsteady compressible magneto-radiative gas (water vapor Pr = 1) flow near a heated vertical wavy wall through porous medium in the presence of inclined magnetic field. The impacts of viscous dissipation, temperature-dependent fluid properties, thermal conductivity and viscosity in the presence of nonlinear thermal radiation are studied. The sinusoidal surface is transformed into a flat one using a suitable transformation. The comparison figures of published data with the present outcomes illustrate a good match. The present steady-state outcomes are presented for the temperature, velocity, Nusselt number and the shearing stress through figures for several interested physical parameters, namely, compressibility, magnetic, radiation, viscosity–temperature variation, thermal conductivity–temperature variation, surface sinusoidal waveform and porous parameters. Findings The present numerical outcomes confirm the importance of applying nonlinear thermal radiation cases in all studies that investigate heat transfer under the influence of thermal radiation. Originality/value A mathematical model is established for a wavy boundary, and Chebyshev pseudo-spectral method is adopted for the numerical study.

In the present contribution, a numerical treatment is provided to describe unsteady nanofluid flow near a vertical heated wavy surface. A memorable feature of the present work is the investigation of nanofluid flow associated with thermal radiation that acts as a catalyst for heat transfer rates. Likewise, the effectiveness of variable viscosity is examined as it controls fluid flow as well as heat transfer. It is necessary to study heat and mass transfer for complex geometries because predicting heat and mass transfer for irregular surfaces is a topic of fundamental importance, and irregular surfaces frequently appear in many applications, such as flat-plate solar collectors and flat-plate condensers in refrigerators. A simple coordinate transformation from the wavy surface into a flat one is employed. The non-dimensional boundary layer equations that governing both heat transfer and nanofluid flow phenomena along the wavy surface are solved via a powerful numerical approach called the implicit Chebyshev pseudospectral (ICPS) method with Mathematica code. A comparison graph of the current numerical computation and the published data shows a perfect match. Figures depict the effect of various physical parameters on nanofluid velocities, temperature, salt concentration, nanoparticle concentration, skin friction, Sherwood, nanoparticle Sherwood, and Nusselt numbers. According to the numerical results, increasing the variable viscosity parameter value causes a drop in the local skin friction coefficient value and an increase in the steady-state axial nanofluid velocity profile near the wavy surface. Furthermore, as heat radiation is increased, the local Nusselt number decreases but the nanoparticle Sherwood number increases.

This paper presents an adaptive approach to optimize field injection strategies using streamline-based well allocations coupled with fuzzy logic. The strength of our approach comes from the fact that streamlines are generated by running a full-physics reservoir simulator. Streamlines provide great insights about well pattern connectivity and good allocation factors allowing the injection efficiency (IE) for each pattern to be determined. Fuzzy logic can simulate human thinking and handle different categories of information including linguistic, imprecise, approximate, and overlapping to name a few. This paper presents a genuine approach for field injection optimization using a streamlined-based fuzzy logic system. In this work, we present an adaptive streamline-based fuzzy logic system that uses three input parameters namely injection efficiency (IE), water cut (WC), and injection loss to aquifer to assign an injector ranking index (IRI) according to injector performances. The workflow then smartly redistributes water injection by accounting for operational constraints and number of connected producers in a pattern in addition to the IRI. The workflow examines the low performers (i.e., low and medium IRI categories) and assigns different injection reduction factors for each injector in these categories. Then, the total amount of reduced injection is assigned to high performers (i.e., high IRI) while ensuring no operational constraint is violated, such as bottom-hole pressure (BHP) and capacity of pumps. This approach has been tested on a dual-porosity dual-permeability (DPDP) conceptual simulation model. The area of interest has two rows of injectors: downdip and updip. The updip injectors are the focus of the study. The results of applying this approach show noticeable improvements in injection efficiency for most wells in the area of interest ensuring better sweep, good pressure support, and improving cumulative oil production. We believe combining both technologies, namely streamlines and fuzzy logic, can provide reservoir engineers with a robust decision-making tool to attain a more successful field-wide water injection strategy.

Background/Objective: Fish is one of the most valuable food for human consumption. However, fish may also act as a source of foodborne pathogens including Aeromonas species which caused a serious threat to a public health concern. This study aimed to investigate the prevalence and virulence characteristics of Aeromonas species isolated from fish farms in Egypt. Methods: A total of 100 random samples of freshwater fish represented by Nile tilapia and Mugil cephalus (50 of each) were collected from different fish farms in Kafr El-Sheikh governorate and examined bacteriologically and biochemically for the presence of Aeromonas species. Multiplex PCR was done to detect some virulence-associated genes in Aeromonas hydrophila isolates. Results: The obtained results revealed that the incidence of Aeromonas species in Nile tilapia and Mugil cephalus were 32 (64%) and 25 (50%), respectively. The most prevalent Aeromonas species isolated from Nile tilapia were Aeromonas caviae 13 (40.6%), Aeromonas hydrophila 8 (25%), Aeromonas sobria 7 (21.9%), Aeromonas veronii 3 (9.4%), and Aeromonas fluvialis 1 (3.1%), while from fresh Mugil cephalus were Aeromonas sobria 11 (44%), Aeromonas caviae 7 (28%), Aeromonas hydrophila 5 (20%), and Aeromonas veronii 2 (8%). The isolated Aeromonas hydrophila concealed some virulence genes responsible for their pathogenicities such as aerolysin gene (aerA) and cytotonic enterotoxin gene (altA). Conclusion: The hygienic measures should be applied to prevent fish contamination with Aeromonas species.

Presence of paleo zone, which frequently exists below Free-Water-Level surface, can impact dynamic reconciliation of reservoir simulation models. The process is even more challenging with embedded complex representations of reservoir connectivity (conductive fractures) and inherent uncertainty associated with geological and flow modeling. We present a rigorous approach that integrates characterization of paleo zone, parameterization of paleo zone conductivity and application of flow profiles as a guide in accelerated history matching study of large-scale Dual Porosity-Dual Permeability model. The presence of immobile oil within paleo zone can cause permeability reduction and inherently limit aquifer support to oil zone. Accordingly, such occurrence can be represented as a low permeability streak or region in the simulation model and leveraged for more accurate calibration of model injection wells located inside the paleo zone. We performed probabilistic sensitivity analysis and parameterization of paleo zone conductivity using Design of Experiments on a synthetic simulation model with optimized aquifer size and strength as the basecase. The outcome of the synthetic sensitivity scenarios using dynamic model strongly indicates that paleo zone is partially sealing. Multiple scoping runs were performed to identify appropriate permeability values required to calibrate the model. The use of multipliers in porositypermeability transform reproduces blocking or baffling effect of the paleo zone, considering this fluid will behave as part of the rock framework. Porosity and permeability were recomputed inside the paleo zone based on Bulk Volume of Water (BVW) data assessment. The higher the BVW the higher the chance to have effective communication between the oil leg and aquifer. These multipliers represent the probability of the sealing character of the paleo zone and reflect on the non-uniform distribution of accumulated hydrocarbons. Above methodology was used to define the initial set of paleo zone petrophysical property modifiers, rendering multiple model realizations within optimistic-pessimistic range. Flow profiles can be used to guide segmentation of paleo zone with preferential well injectivity to further improve the efficiency of history matching process. Our paper demonstrates a successful application of multi-variate characterization and modeling of paleo zone geometry and properties for a history match of a conceptual, complex reservoir simulation model under reservoir uncertainty. An innovative approach to probabilistic parameterization of paleo zone conductivity has contributed to a model with exceptionally high quality and rendered a reservoir simulation model with reliable predictive capability in accelerated time.

This study aimed to evaluate the effectiveness of tocilizumab in mechanically ventilated patients with coronavirus disease 2019 (COVID-19). This retrospective multicenter study included adults (≥18 years) diagnosed with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by real-time polymerase chain reaction (RT-PCR) from nasopharyngeal swab, and requiring invasive mechanical ventilation during admission. Survival analyses with inverse propensity score treatment weighting (IPTW) and propensity score matching (PSM) were conducted. To account for immortal bias, we used Cox proportional modeling with time-dependent covariance. Competing risk analysis was performed for the extubation endpoint. A total of 556 (tocilizumab = 193, control = 363) patients were included. Males constituted the majority of the participants (69.2% in tocilizumab arm,74.1% in control arm). Tocilizumab was not associated with a reduction in mortality with hazard ratio [(HR) = 0.82,95% confidence interval (95%CI): 0.62–1.10] in the Inverse propensity score weighting (IPTW) analysis and (HR = 0.86,95% CI: 0.64–1.16) in the PSM analysis. However, tocilizumab was associated with an increased rate of extubation (33.6%) compared to the control arm (11.9%); subdistributional hazards (SHR) = 3.1, 95% CI: 1.86–5.16). Although tocilizumab was not found to be effective in reducing mortality, extubation rate while on mechanical ventilation was higher among tocilizumab treated group.

Single-walled carbon nanotubes (SWNTs) and multi-walled nanotubes (MWNTs) are gaining appeal in mechanical engineering and industrial applications due to their direct influence on enhancing the thermal conductivity of base fluids. With such intriguing properties of carbon nanotubes in mind, our goal in this work is to investigate radiation effects on the flow of carbon nanotube suspended nanofluids in the presence of a magnetic field past a stretched sheet impacted by slip state. CNTs flow and heat transmission are frequently modelled in practice using nonlinear differential equation systems. This system has been precisely solved, and an accurate analytical expression for the fluid velocity in terms of an exponential function has been derived, while the temperature distribution is stated in terms of a confluent hypergeometric function. The impact of the radiation parameter, slip parameter, sloid volume fraction, magnetic parameter, Eckart and Prandtl numbers on the velocity, temperature, and heat transfer rate profiles are demonstrated using a parametric analysis. When compared to the two types of nanoparticles (Cooper and Silver) in earlier published articles, temperature profiles for single-walled nanotubes (SWNTs) and multi-walled nanotubes (MWNTs) are revealed to be particularly sensitive to radiation, solid volume fraction, and slip parameters. Nanomechanical gears, nanosensors, nanocomposite materials, resonators, and thermal materials are only a few of the present problem's technical applications.

The flow of nanofluids past a stretching sheet has attracted much attention due to its wide applications in industry and engineering. Theoretical and numerical solutions have been discussed in this paper for studying the effect of suction or injection on flow of nanofluids past a stretching sheet. In the absence of thermophoresis the analytical exact solution of the stream function was obtained in terms of exponential function, while the exact solutions for temperature and nanoparticle volume fraction were obtained in terms of the generalized incomplete gamma function. In addition, in the presence of thermophoresis, the exact solutions are not available. Therefore, the numerical results, carried out by using Chebyshev collocation method (ChCM). It is found that a good agreement exists between the present results and with those published works. Useful results for temperature profile, concentration profile, reduced Nusselt number and reduced Sherwood number are discussed in details graphically. It was also demonstrated that both temperature and concentration profiles decrease by an increase from injection to suction. Finally, the present results showed that increase of the wall mass transfer from injection to suction decreased both reduced Nusselt number and the reduced Sherwood number when Brownian motion parameter and Lewis number increased.

A total of 100 samples of imported frozen liver were randomly collected from different markets at El-Gharbiah governorate, Egypt.The samples were examined for detection of molds and determination of aflatoxins produced by their aflatoxigenic strains. The results showed that 33 % of the samples were contaminated with different mold species and the average mold count (/g)was 3.8 × 104± 8.2× 103/g. Genus Aspergilluswasthe predominant species detected in the positive samples (54.55 %) followed by Genus Penicillium(51.52%). The positive samples were examined for extraction and estimation of aflatoxins B1, B2, G1 and G2 using HPLC. The results indicated that aflatoxins B1, B2, G1 and G2 were detected in 24.2, 21.2, 18.2 and 15.1% of such liver samples, respectively. These results showed that imported frozen liver can represent a potential source of variousmold species and their toxinsconstituting, at times, a public health hazard.

In this paper, the effect of partial slip boundary condition on the heat and mass transfer of the Cu-water and Ag-water nanofluids over a stretching sheet in the presence of magnetic field and radiation. Such partial slip boundary condition has attracted much attention due to its wide applications in industry and chemical engineering. The flow is basically governing by a system of partial differential equations which are reduced to a system of ordinary differential equations. This system has been exactly solved, where exact analytical expression has been obtained for the fluid velocity in terms of exponential function, while the temperature distribution, and the nanoparticles concentration are expressed in terms of the generalized incomplete gamma function. In addition, explicit formulae are also derived from the rates of heat transfer and mass transfer. The effects of the permanent parameters on the skin friction, heat transfer coefficient, rate of mass transfer, velocity, the temperature profile, and concentration profile have been discussed through tables and graphs.

Laboratory studies of Smartwater flood have demonstrated its impact on increasing oil recovery. Smartwater refers to the injection water that is subjected to alteration of total salinity or ionic composition. Several simulation techniques are carried out to match experimental observations. The objective of the paper is to critically examine and assess the simulation practices in the industry. Simulation strives to depict the production profiles along with the primary chemical and physical processes that take place. The simulation studies in the literature were surveyed and classified into categories based on the simulation approach. The capability of the simulation techniques to mimic the oil recovery mechanisms were evaluated. In addition, we explored the operational advantages and limitations of each technique. Most of the simulation techniques estimate the increase in oil recovery mainly from the changes of the relative permeability curves and residual oil saturation. A correlation is often established between these data sets and certain traceable factors such as the total salinity. We identified two adopted modeling categories: single component, and mechanistic reaction models. The single component model is the most commonly used because it requires few additional input data with relatively lower uncertainty. The mechanistic reaction model is a new emerging method that accounts for oil-water-rock interactions. The main limitation of this method is that most simulators are not equipped with chemical reaction functions. In such a case, an external simulation package is required to simulate the reactions. The paper concludes that themechanistic reaction model is an excellent options to replicate the micro-scale processes. Integrating the conventional simulators with chemical reaction functions is required to improve the simulation efficiency and accuracy. There is a gap in the literature between investigating oil recovery mechanisms associated with Smartwater flood and reflecting them in the conventional fluid-flow simulation. To motivate more efforts and bridge the gap, this review provides insights of the recent advancements in the simulation techniques and addresses the expectations from each technique.

Muscular involvement with Echinococcusgranulosus is rare, even in endemic countries where the frequency is estimated to be less than 3%, particularly in the countries of the Mediterranean basin, North Africa and Latin America. We report the rare observation of a hydatid cyst of the anterior thigh room in a 26-year-old patient of rural origin with no significant history and was hospitalized in our department for the exploration of a tumefaction Of the antirior surface of the left thigh appeared gradually and insidiously for 6 months. Magnetic resonance imaging (MRI) showed an oval mass evoking an intramuscular hydatid cyst and its relationship to neighboring structures. She underwent surgical excision under locoregional anesthesia. Solitary hydatid localization in muscle tissue is exceptional, but useful to know. Its diagnosis is often delayed, its treatment is surgical, but recurrences are possible.