Simple and Safe Packing Method for High-Grade Liver Injuries

Background: Injury to the liver is a commonly encountered problem in trauma cases and is a frequent cause of morbidity and mortality. Because gauze packing is easy to use and has the potential for rapid hemorrhage control, it is the most commonly used method for patients with severe liver injuries, particularly those with coagulopathy. Objectives: In this study, OpSite sheets were used to make three-layer packs for decreasing the complication associated with removing gauze packing. Patients and Methods: Twenty male patients with grade IV or V liver injuries that required laparotomy were enrolled in the study. Ten patients were treated using conventional packing, while the other 10 were treated using the three-layer pack. In the case group, the liver was mobilized as much as possible. The three-layer pack was then placed at the site of liver damage and extended onto the liver surface, and the other pads were placed on top of this pad. After 72 h, reoperation was performed, the packs were removed, and the packs causing injury were recorded. Additionally, if rebleeding due to the adhesive bands of the pack was observed, the blood was suctioned and bleeding volume was measured. Data were analyzed using the Mann–Whitney test. Results: Patients in the case and control groups were similar in age and admission vital signs. During the second operation, the bleeding volumes measured in the case and control groups were 66 ± 27.01 mL and 152 ± 85.4 mL, respectively. There was some pad-induced damage after the removal of the pad in the control group. Conclusions: Our study has provided a simple and safe packing method for high-grade liver injuries

Structural shape optimization using Cartesian grids and automatic h-adaptive mesh projection

[EN] We present a novel approach to 3D structural shape optimization that leans on an Immersed Boundary Method. A boundary tracking strategy based on evaluating the intersections between a fixed Cartesian grid and the evolving geometry sorts elements as internal, external and intersected. The integration procedure used by the NURBS-Enhanced Finite Element Method accurately accounts for the nonconformity between the fixed embedding discretization and the evolving structural shape, avoiding the creation of a boundary-fitted mesh for each design iteration, yielding in very efficient mesh generation process. A Cartesian hierarchical data structure improves the efficiency of the analyzes, allowing for trivial data sharing between similar entities or for an optimal reordering of thematrices for the solution of the system of equations, among other benefits. Shape optimization requires the sufficiently accurate structural analysis of a large number of different designs, presenting the computational cost for each design as a critical issue. The information required to create 3D Cartesian h- adapted mesh for new geometries is projected from previously analyzed geometries using shape sensitivity results. Then, the refinement criterion permits one to directly build h-adapted mesh on the new designs with a specified and controlled error level. Several examples are presented to show how the techniques here proposed considerably improve the computational efficiency of the optimization process.The authors wish to thank the Spanish Ministerio de Economia y Competitividad for the financial support received through the project DPI2013-46317-R and the FPI program (BES-2011-044080), and the Generalitat Valenciana through the project PROMETEO/2016/007.Marco, O.; Ródenas, J.; Albelda Vitoria, J.; Nadal, E.; Tur Valiente, M. (2017). 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Tailoring the separation performance and fouling reduction of PES based nanofiltration membrane by using a PVA/Fe3O4 coating layer

© 2019 Institution of Chemical Engineers In the current research, the surface of a polyethersulfone (PES) nanofiltration membrane was modified by polyvinyl alcohol (PVA) and iron-oxide nanoparticles (Fe 3 O 4 ) through a crosslinking reaction with glutaraldehyde (GA).The effect of the coating layer on the morphology, physico-chemical properties, separation and antifouling performance of the membranes was studied. The analysis of FTIR spectra, scanning electron microscopy (SEM), atomic force microscopy (AFM), porosity and mean pore size measurement, contact angle analysis, salt rejection and filtration of a powder milk solution was the basis of membrane characterization. Surface and cross-sectional SEM images showed the formation of a dense layer on the PES based NF membrane after coating. The pure water flux, porosity and mean pore size were decreased; the water contact angle was slightly lower due to the hydrophilic nature of PVA and Fe 3 O 4 nanoparticles. The surface roughness initially decreased for a coating with a low concentration of nanoparticles but increased when a higher amount of nanoparticles was used. The salt rejection significantly increased from 68.4% for a bare PES membrane to 94% for the modified ones (sample 6) by surface modification. Filtration of a powder milk solution revealed the best antifouling performance for the membrane modified by PVA/Fe 3 O 4 (2 wt %).status: publishe

Isolation and removal of cyanide from tailing dams in gold processing plant using natural bitumen

Gilsonite as a natural occurrence of bitumen and due to the presence of carbon in its structure is a suitable adsorbent for a wide variety of pollutants. In this research, the adsorption of cyanide from the wastewater of gold processing plants using gilsonite were investigated. In this way, the effect of particle size of gilsonite, the weight and mixing time with solution, on the amount of cyanide adsorption have been studied. In addition, in one experiment, the effect of processed gilsonite on its adsorption ability was investigated. Based on the obtained results, the maximum adsorption of 61.64 was obtained in the size range of �1+0.5 and �2+1 mm of gilsonite. With increasing adsorbent weight and mixing time, the cyanide adsorption rate were increased. On the other hand, with the processing of the gilsonite sample, the amounts of adsorption were increased considerably. This study indicated that gilsonite can be used as an isolation and absorbent in the structure and floor of the tailing dumps of mineral processing plants. © 2020 Elsevier Lt

Novel composite graphene oxide/chitosan nanoplates incorporated into PES based nanofiltration membrane: Chromium removal and antifouling enhancement

© 2018 The Korean Society of Industrial and Engineering Chemistry In this work, novel nanofiltration membranes with outstanding performance and antifouling properties were fabricated by incorporating composite graphene oxide/chitosan (GOC) nanoplates into the membrane structure. GOC composite nanoplates were prepared by surface modification of GO with chitosan. The GOC nanoplates were then introduced as additives in a polymeric phase in different concentrations (up to 1%) in view of membrane synthesis. these membranes were thoroughly characterized and assessed for their Na2SO4 and CrSO4 rejection and water flux. Furthermore, the antifouling performance of GO and GOC filled membranes in high concentration (1 wt%) was investigated. Modified membranes with addition of GOCs showed a higher hydrophilicity, pure water flux and rejection, and a smoother surface compared to a bare PES and a GO incorporated membrane. SEM surface images indicated a more uniformed distribution of GOCs at a high loading rate (1 wt%) compared to GO. Due to the uniform dispersion of GOCs, a better antifouling performance was observed than for GO filled membranes. The results indicate that surface modification of GO with chitosan can enhance the membrane performance and properties, due to availability of sites with higher activity.status: publishe

Desalination and heavy metal ion removal from water by new ion exchange membrane modified by synthesized NiFe <inf>2</inf> O <inf>4</inf> /HAMPS nanocomposite

© 2019, Springer-Verlag GmbH Germany, part of Springer Nature. Magnetic nickel ferrite (NiFe 2 O 4 ) nanoparticles were synthesized and then modified by a novel hydrogel based on 2-acrylamido-2-methyl propane sulfonic acid (HAMPS). Field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR) analyses were conducted to prove the NiFe 2 O 4 /HAMPS nanocomposite formation decisively. The effect of NiFe 2 O 4 /HAMPS in the matrix of the heterogeneous cation exchange membrane on separation performance was studied. Adding of NiFe 2 O 4 /HAMPS into the membrane body up to 1%wt resulted in an increase of sodium flux obviously. The sodium flux showed a decreased trend at higher nanocomposite ratios slightly. Membrane potential, permselectivity, and transport numbers also showed improving trends. Results exhibited more value for Na + dynamic transport numbers compared to static ones. Membrane water content and porosity increased from 13.07 to 27.7% and 9.6 to 20.2% by utilizing NiFe 2 O 4 /HAMPS, respectively. By adding NiFe 2 O 4 -HAMPS into the membrane structure a pronounced improvement in membrane mechanical resistance (~ 94%) and chemical stability was observed. Modified membrane containing 1.0%wt NiFe 2 O 4 -HAMPS showed effective separation in Pb 2+ (~ 98%), Cu 2+ (~ 48%), and Ni 2+ (~ 34%) removal. This sample also showed highest current efficiency (78.9%) in Pb 2+ removal and lowest energy consumption (6.97 W/mol) compared to others.status: publishe

PREDICTION OF VAPOR LIQUID EQUILIBRIUM (VLE) DATA FOR BINARY SYSTEMS; CASE STUDY: METHANE/TETRAFLUOROMETHANE

ABSTRACT In this research, the ability of multilayer perceptron neural networks to estimate vapor liquid equilibrium data have been studied. Isothermal vapor-liquid equilibrium (VLE) data for the binary mixture of methane (R50) + tetrafluoromethane (R14) have been investigated at (159.61, 161.58, 169.38, 173.90, and 178.93) K. Two different models with one hidden layer consisted of five hidden neurons are developed as the optimal structures. For this binary system, uncertainties of ANN models were 0.14, 0.26%. In addition, the abilities of ANNs are shown by comparisons with Margules, van Laar, and some other correlations