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Enhanced Recovery After Surgery protocols have demonstrated decreased complication rates and length of stay. However, the influence of mental health on Enhanced Recovery After Surgery success is unknown. A retrospective study of patient-reported outcomes for physical and mental health. We included patients who underwent elective minimally invasive colon resections, who completed the Patient-Reported Outcomes Measurement Information System 10 questionnaire preoperatively, and who had successful implementation of perioperative Enhanced Recovery After Surgery components. We evaluated the predictors of having successful expected Enhanced Recovery After Surgery outcomes using a multiple logistic regression, controlling for baseline patient characteristics, history of a mental health diagnosis, inpatient opiate use, and preoperative Patient-Reported Outcomes Measurement Information System 10 scores. In total, 163 patients met inclusion criteria, with 23% failing Enhanced Recovery After Surgery, and 32% having a preoperative mental health diagnosis. The most common reason for failure of expected Enhanced Recovery After Surgery outcomes was length of stay (55.3%) followed by postoperative ileus (31.6%). Age, sex, the American Society of Anesthesiologists physical status classification, and preoperative Patient-Reported Outcomes Measurement Information System 10 scores were not significantly different between those who failed or succeeded, whereas length of stay was typically longer for those who failed Enhanced Recovery After Surgery (5.7 days failure vs 2.2 days success, P <.001). Patients with a previous mental health diagnosis, where depression and anxiety were most common, had significantly lower odds of successfully meeting expected Enhanced Recovery After Surgery outcomes (odds ratio of 0.23, 95% confidence interval: 0.09–0.55, P =.001). Patients with a mental health diagnosis have a lower likelihood of successfully meeting expected Enhanced Recovery After Surgery outcomes. The majority of these patients self-report normal mental and physical health preoperatively, indicating that even well-controlled mental health diagnoses have a negative impact on Enhanced Recovery After Surgery success. [ABSTRACT FROM AUTHOR]

In this study, undoped and Al-doped BiFeO 3 (Bi 1−x Al x FeO 3 : x = 0.0, 0.05, 0.1 and 0.15) nanoparticles were successfully prepared by solution combustion method using urea as the fuel. The obtained product was sintered at 550 °C for 2 h to obtain pure phase. The as-prepared samples were characterized by powder XRD, FT-IR, FE-SEM, EDX, TEM, UV-Vis absorption and PL spectroscopic analysis. Powder XRD study revealed that the synthesized nano-powders exhibit rhombohedral structure. The average crystallite size of the samples decreased from 56.25 to 48.55 nm with “x”. Surface morphology of the samples were analyzed by FE-SEM and TEM micrograph technique and the grain distribution was not quite homogeneous and observed agglomeration, which is mainly due to the magnetic interaction among the particles. EDX analysis showed that the presence of Bi, Fe, O and Al peaks only without any form of impurity peak in all products. PL spectroscopy showed a high intense peak at 464 nm, which was attributed to blue emission. Antibacterial activity of Bi 1−x Al x FeO 3 nanoparticles was found to be enhanced with increase in Al doping concentration as it caused a reduction in the grain size of the samples. [ABSTRACT FROM AUTHOR]

Micro scale structures like beams and plates are used in several micro sensors and actuators, micro level energy harvesters and atomic force microscopes. During their manufacture and in the service condition, micro level voids and cracks are developed on their edges and surfaces. These result-in increasing vibration amplitudes and eventual catastrophic failures. Present work deals with the transient dynamic analysis of bi-directional functionally graded material microbeams with edge cracks resting on nonlinear elastic foundations in the presence of thermal shock loads. The dynamic equations of the beam are derived from Hamilton principle by considering modified couple stress theory and the equations of motion are solved through the finite element model. Natural frequencies of the FG beam are calculated for different boundary conditions and thermal shock response is obtained for different grading indices. Effects of crack parameters, support stiffness and thermal loads on the natural frequencies are studied. The input power flow analysis of the cracked FG microbeam is also conducted. In order to identify the crack depth and location, inverse based optimization methodology is illustrated through minimization of error functions derived from natural frequencies and input power flow. A surrogate scheme with firefly metaheuristic optimization employing back propagation neural network regression model is proposed for obtaining the effective solution. • Dynamic analysis of cracked FG micro beams under thermal shock loads is conducted. • Response of microbeam is studied using a three parameter nonlinear viscoelastic foundation. • Crack parameters are identified through minimization of error function derived from natural frequencies and input power flow. • A surrogate model based optimization technique is employed to obtain the crack parameters with higher accuracy. [ABSTRACT FROM AUTHOR]

Polymer matrix nanocomposites reinforced with uniformly dispersed and randomly oriented multi-walled carbon nanotubes (MWCNTs) are identified as excellent candidates for functionally graded structural members. This paper presents static and dynamic behavior of functionally graded polymer composite plates reinforced by randomly oriented multi-walled carbon nanotubes using novel layer-wise formulation concept. The weight fraction of MWCNTs in functional graded plate is represented by layer-wise variation along the thickness and MWCNTs are considered as uniformly dispersed in each layer. The effective elastic modulus of nanocomposite plate is predicted with modified Halpin-Tsai model, while the Poisson’s ratio and density are determined by rule of mixtures. System of governing equations are derived based on generalized higher order shear deformation (HSDT) plate theory and Navier technique is employed to obtain the solution for free-vibration, buckling and static bending problems of simply supported plates under axial and transverse loading conditions at various aspect-ratios. In order to understand the effect of important reinforcement and plate parameters on the natural frequencies, critical buckling loads and bending deflections, different parametric studies are conducted. Results reveal that different types of weight distributions have significant influence on structural characteristics. [ABSTRACT FROM AUTHOR]

Catalog maintenance for Space Situational Awareness (SSA) demands an accurate and computationally lean orbit propagation and orbit determination technique to cope with the ever increasing number of observed space objects. As an alternative to established numerical and analytical methods, we investigate the accuracy and computational load of the Draper Semi-analytical Satellite Theory (DSST). The standalone version of the DSST was enhanced with additional perturbation models to improve its recovery of short periodic motion. The accuracy of DSST is, for the first time, compared to a numerical propagator with fidelity force models for a comprehensive grid of low, medium, and high altitude orbits with varying eccentricity and different inclinations. Furthermore, the run-time of both propagators is compared as a function of propagation arc, output step size and gravity field order to assess its performance for a full range of relevant use cases. For use in orbit determination, a robust performance of DSST is demonstrated even in the case of sparse observations, which is most sensitive to mismodeled short periodic perturbations. Overall, DSST is shown to exhibit adequate accuracy at favorable computational speed for the full set of orbits that need to be considered in space surveillance. Along with the inherent benefits of a semi-analytical orbit representation, DSST provides an attractive alternative to the more common numerical orbit propagation techniques. [ABSTRACT FROM AUTHOR]

This paper presents modelling and dynamic analysis of an on-board rotor with base excitation. A flexible shaft and rigid disc model is considered for idealizing a turbocharger rotor. The nonlinear hydrodynamic journal bearing forces are computed and the discretized equations of motion using finite element method are solved with time integration scheme. The disc unbalance forces are also accounted. The instability regions are identified by inducing varying sinusoidal support excitations. The work gives insights in design of the automobile engine turbocharger rotor mounted on hydrodynamic journal bearings supported with viscoelastic springs. [ABSTRACT FROM AUTHOR]

This paper presents an optimization methodology for achieving minimum actuation torques of a kinematically redundant planar parallel mechanism following a desired trajectory using binary coded Genetic Algorithms (GA). A user interactive computer program developed in present work helps for obtaining inverse kinematic solution and Jacobian matrices at a given Cartesian coordinate location of the end-effector. Furthermore, the joint torques are obtained from the end-effector forces (wrench) using Jacobian matrix at every location. The resultant joint torque vector can be used to describe the objective function. The variables of the optimization problem are redundant base prismatic joint displacements and the constraints include the variable bounds and the pre-defined trajectory lying within the original workspace. The outputs of the kinematically-redundant 3-PRRR manipulator are compared against the results for a non-redundant 3-RRR manipulator. The results show that the redundant manipulator gives relatively lower input torques. Also, it is observed that while passing through singular configurations on the trajectory, finite values of torques are achieved. Results are shown for a straight-line trajectory. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the stiffening effect of carbon nanotubes dispersed in polymer composites using micromechanics models and finite element analysis. The effective elastic modulus of carbon nanotube (CNT)-reinforced composites is predicted by assuming that all the CNTs are either aligned or randomly oriented in the polymer matrix. An extended three-phase rule of mixture is implemented to analyze the effect of interphase properties on the effective elastic modulus. Homogenized representative volume element with multiple CNTs embedded inside the matrix with an interface layer is employed. The analysis is performed using a 3D finite element model of the representative volume element. Effects of interface stiffness, its thickness and dispersion of CNTs within the polymer matrix are studied. Results reveal the extent these factors influencing the elastic modulus of the composite. [Copyright &y& Elsevier]

Abstract: In this paper, the problem of steady Poiseuille flow of two immiscible incompressible micropolar fluids between two horizontal parallel plates of a channel with constant wall temperatures is studied in terms of entropy generation. The flow is assumed to be governed by Eringen’s micropolar fluid flow equations. The flow region is divided into two zones, the flow of the heavier fluid taking place in the lower zone-I. No slip condition is taken on the plates and at the interface continuity of velocity, micro-rotation, temperature, heat flux and shear stresses is imposed. The velocity, micro-rotation and temperature fields are derived analytically. The dimensionless quantities-entropy generation number (Ns), Bejan number (Be) and irreversibility ratio (ϕ) are analytically derived. The effects of material parameters like micropolarity (c i ), couplestress (s i ) on the velocity, micro-rotation and temperature are investigated. The derived equation for the dimensionless entropy generation number is used to interpret the relative importance of frictions to conduction by varying viscous dissipation parameter. The entropy generation near the plates increases more rapidly in fluid I than in fluid II as viscous dissipation effects become more important in zone I. The velocity and temperature profiles are found to be in good agreement with the distributions of the dimensionless entropy generation number (Ns). [Copyright &y& Elsevier]

Abstract: Soybean meal, a co-product after oil extraction from seeds, is rich in protein. Our objective was to utilize this co-product, obtain gastrointestinal (GI) resistant peptides from the isolated protein, and test for bioactivity against colon, liver and lung cancer cell lines. N98-4445A, S03-543CR high oleic acid soybean lines, and R95-1705 high protein soybean line were used for this study. Protein isolates were prepared at alkaline pH and hydrolyzed using alcalase enzyme to generate peptide hydrolysates. After determining gastrointestinal resistance of the peptide hydrolysates they were fractionated into definite molecular sizes of <5kDa, 5–10kDa, and 10–50kDa and tested against human colon (HCT-116, Caco-2), liver (HepG-2) and lung (NCL-H1299) cancer cell lines. MTS, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H-tetrazolium, cytotoxicity assay was performed to test in vitro cancer cell viability upon treatment with peptide fractions. The peptide fractions from N98-4445A and S03-543CR lines showed cell growth inhibition of 73% of colon cancer (HCT-116), 70% of liver cancer cells and 68% of lung cancer cells. Dose response showed that the peptides had significant inhibitory effect at higher concentrations (1000μg/mL to 600μg/mL) and gradually decreased with decreased dosage (500μg/mL to 100μg/mL). Reverse phase HPLC identified three single peptides from the 10–50kDa fractions of N98-4445A soy line that have potential for enhanced activity. Soybean peptide fractions can thus be a source of bioactivity against colon, liver and lung cancer cell proliferation. [Copyright &y& Elsevier]

Abstract: This paper presents results of linear stability analysis in turning using nonlinear force–feed dynamic model by considering three-dimensional cutting tool geometry. The modified analytical equations for cutting insert with three-dimensional tool geometry are derived by including relative displacements of the tool with respect to a two-degree of freedom work-piece model. The critical stability points obtained as a function of feed are validated against time-domain solutions. Simulation results are shown in the form of limit cycles and bifurcation diagram. Influence of static-feed term on cutting dynamics over a cantilever work-piece is illustrated along with the experimental results. [Copyright &y& Elsevier]

Abstract: This paper proposes an optimization methodology for the selection of best process parameters in electro-discharge machining. Regular cutting experiments are carried out on die-sinking machine under different conditions of process parameters. The system model is created using counter-propagation neural network using experimental data. This system model is employed to simultaneously maximize the material removal rate as well as minimize the surface roughness using simulated annealing scheme. Finally consistency of the method is tested with several initial trail values. Results are shown in the form of tables and figures. [Copyright &y& Elsevier]

Little is known about the pathogenesis of Entamoeba histolytica and how epithelial cells respond to the parasite. Herein, we characterized the interactions between E. histolytica and colonic epithelial cells and the role macrophages play in modulating epithelial cell responses. The human colonic epithelial cell lines Caco-2 and T84 were grown either as monoculture or co-cultured in transwell plates with differentiated human THP-1 macrophages for 24 h before stimulation with soluble amebic proteins (SAP). In naive epithelial cells, prolonged stimulation with SAP reduced the levels of heat shock protein (Hsp) 27 and 72. However in THP-1 conditioned intestinal epithelial cells SAP enhanced Hsp27 and Hsp72, which was dependent on the activation of ERK MAP kinase. Hsp synthesis induced by SAP conferred protection against oxidative and apoptotic injuries. Treatment with SAP inhibited NF-κB activation induced by interleukin-1β; specifically, the NF-κB-DNA binding, nuclear translocation of p65 subunit, and phosphorylation of IκB-α were reduced. Gene silencing by small interfering RNA confirmed the role of Hsp27 in suppressing NF-κB activation at IκB kinase (IKK) level. By co-immunoprecipitation studies, we found that Hsp27 interacts with IKK-α and IKK-β, and this association was increased in SAP-treated conditioned epithelial cells. Overexpression of wild type Hsp27 amplified the effects of SAP, whereas a phosphorylation-deficient mutant of Hsp27 abrogated SAP-induced NF-κB inhibition. In conditioned epithelial cells, Hsp27 was phosphorylated at serine 15 after prolonged exposure to SAP. This mechanism may explain the absence of colonic inflammation seen in the majority of individuals infected with E. histolytica. [ABSTRACT FROM AUTHOR]

This paper proposes a method of locating and quantifying the damage in structural members using the concept of residual forces. To describe the damage in a structure, finite element (FE) models are parameterised by structural stiffness reduction parameters. The damage parameters are determined by minimising a global error derived from dynamic residual vectors, which are obtained by introducing a simulated “experimental” data into the eigenproblem. An eigenvalue prediction algorithm along with normalised residual function is employed to formulate the objective function. Two-point crossover binary coded genetic algorithm (GA) with tournament selection approach is adopted in minimising the objective and optimum set of stiffness reduction parameters are predicted. Current structural defect-identification scheme is verified and assessed using an analytically derived plane truss, a cantilever Euler–Bernoulli beam and a portal truss. Results are presented in the form of tables and graphs. [Copyright &y& Elsevier]

Gastrointestinal mucin is a constituent of luminal barrier function and is the first line of host defense against invading pathogens. Mucin carbohydrates and amino acids, as well as trapped soluble host defense molecules, serve as substrates for colonization and control or deter pathogen invasion to the underlying mucosal epithelial cells. Toll-like receptors on the surface of epithelial cells act as sensors for invading pathogens, and the ensuing host response limits parasite invasion and leads to adaptive immunity. The latest work in the field and the use of parasite model systems to illustrate the delicate host-parasite interaction at the mucosal surface of the gut are discussed here. [Copyright &y& Elsevier]

Supersonic combustion was experimentally investigated in a strut-cavity based scramjet combustor with kerosene and pilot hydrogen as fuels. Strut-cavity is the space between two tandem struts in streamwise direction. The occurrence of cavity induced pressure oscillations in the strut-cavity was confirmed through cold flow experiments. The dominant modes of pressure oscillations were strongly influenced by the cavity aspect ratio. A ventilated rear wall (VRW), which is a new passive control device, was adopted in the strut-cavity. The strut-cavity with the VRW attenuated pressure oscillations better than the ‘ramp rear wall’ configuration. A scramjet combustor was realized with two strut-cavities in tandem for mixing enhancement and a strut-cavity with the VRW for flame stabilization. The combustor was tested at the following inlet conditions: total pressure of 4.89 bar, total temperature of 1517 K, and Mach number of 2. Supersonic combustion was observed. Steep increase in static pressure in the region of the strut-cavity with the VRW indicated that the flame was stabilized. The combustor was operated at a wide range of equivalence ratios (0.3–0.7) without inlet interactions. The total pressure at the combustor exit plane indicated that the flow was uniform, except at the central region. The total pressure loss and combustion efficiency of the combustor were evaluated for various equivalence ratios. [ABSTRACT FROM AUTHOR]

Soy proteins when prepared to high purity can confer good functional properties and the whey by-product is a potential source for bioactivity. In this study, we determined the protein, moisture, fiber, solubility, foaming, emulsion properties, as well as Angiotensin-I converting enzyme (ACE-I) inhibitory activity of prepared soy–whey proteins and its fractions. The soy–whey proteins were fractionated into < 5, > 5, > 10, and > 50 kDa using ultrafiltration. The expanded AACC methods were used to determine protein, moisture, and fiber analyses of the whey and its fractions. Solubility method was conducted to determine the protein solubility profile of the soy–whey and its fractions at varying pHs. Turbidimetric method was used to evaluate emulsifying activity (EA) and emulsion stability (ES). There were significant differences observed in moisture, protein and salt contents between unfractionated, > 50 kDa and smaller sized fractions. No significant differences were observed with phytic acid and total dietary fiber contents among all samples. The unfractionated whey protein and > 50 kDa fraction showed better solubility than other fractions. Unfractionated whey protein had the highest foam capacity (42.7 mL) while the fraction > 5 kDa showed the greatest foaming stability (46 min). The highest emulsion activity (0.33 ± 0.1) and stability (825.1 ± 45.1) was obtained with the > 50 kDa fraction while the unfractionated whey protein had the highest ACE-I inhibition activity. The findings indicate that soy–whey protein fraction (> 50 kDa) had good solubility, emulsion activity and stability, while the unfractionated whey protein exhibited the strongest ACE-I inhibition percentage (19%). [ABSTRACT FROM AUTHOR]

Background: To optimize responsible opioid prescribing after inpatient operation, we implemented a clinical trial with the following objectives: prospectively validate patient-centered opioid prescription guidelines and increase the FDA-compliant disposal rate of leftover opioid pills to higher than currently reported rates of 20% to 30%.Study Design: We prospectively enrolled 229 patients admitted for 48 hours or longer after elective general, colorectal, urologic, gynecologic, or thoracic operation. At discharge, patients received a prescription for both nonopioid analgesics and opioids based on their opioid usage the day before discharge: if 0 oral morphine milligram equivalents (MME) were used, then five 5-mg oxycodone pill-equivalents were prescribed; if 1 to 29 MME were used, then fifteen 5-mg oxycodone pill-equivalents were prescribed; if 30 or more MME were used, then thirty 5-mg oxycodone pill-equivalents were prescribed. We considered patients' opioid pain medication needs to be satisfied if no opioid refills were obtained. To improve FDA-compliant disposal of leftover pills, we implemented patient education, convenient drop-box, reminder phone call, and questionnaire.Results: Our opioid guideline satisfied 93% (213 of 229) of patients. Satisfaction was significantly higher in lower opioid usage groups (p = 0.001): 99% (99 of 100) in the 0 MME group, 90% (91 of 101) in the 1 to 29 MME group, and 82% (23 of 28) in the 30 or more MME group. Overall, 95% (217 of 229) of patients used nonopioid analgesics. Sixty percent (138 of 229) had leftover pills; 83% (114 of 138) disposed of them using an FDA-compliant method and 51% (58 of 114) used the convenient drop-box. Of 2,604 prescribed pills, only 187 (7%) were kept by patients.Conclusions: This clinical trial prospectively validated a patient-centered opioid discharge prescription guideline that satisfied 93% of patients. FDA-compliant disposal of excess pills was achieved in 83% of patients with easily actionable interventions. [ABSTRACT FROM AUTHOR]