Computational Parametric Analysis of Cellular Solids with the Miura-Ori Metamaterial Geometry under Quasistatic Compressive Loads

Origami-based metamaterials have widespread application prospects in various industries including aerospace, automotive, flexible electronics, and civil engineering structures. Among the wide range of origami patterns, the fourfold tessellation known as Miura-ori is of particular attraction to engineers and designers. More specifically, researchers have proposed different 3D structures and metamaterials based on the geometric characteristics of this classic origami pattern. Herein, a computational modeling approach for the design and evaluation of 3D cellular solids with the Miura-ori metamaterial geometry which can be of zero or nonzero thicknesses is presented. To this end, first, a range of design alternatives generated based on a numerical parametric model is designed. Next, their mechanical properties and failure behavior under quasistatic axial compressive loads along three perpendicular directions are analyzed. Then, the effects of various geometric parameters on their energy absorption behavior under compression in the most appropriate direction are investigated. The findings of this study provide a basis for future experimental investigations and the potential application of such cellular solids for energy-absorbing purposes.     

Mathematical Modeling of Coke Formation and Deposition due to Thermal Cracking of Petroleum Fluids

A two‐dimensional mathematical dynamics model is presented to predict coke formation due to thermal cracking inside the tubes of fired heaters on two types of petroleum fluid. The laminar and turbulent flows are analyzed for both petroleum fluids. The second‐order k‐? standard model is adopted to make this mathematical model more accurate than previous models of coke formation. The radial and axial variations for temperature, velocity, and concentration due to the high temperature gradients inside the tubes are considered in the model equations. The finite volume method is the numerical model used to discretize the conservation equations. The proposed model is suitable to predict coke formation inside heater tubes since it indicates operational conditions where coke formation is minimized.     

Soft computing methodologies for estimation of energy consumption in buildings with different envelope parameters

In this study, soft computing methods are designed and adapted to estimate energy consumption of the building according to main building envelope parameters such as material thicknesses and insulation K-value. In order to predict the building energy consumption, novel intelligent soft computing schemes, support vector regression (SVR), and adaptive neuro-fuzzy inference system (ANFIS) are used. The polynomial, linear, and radial basis function (RBF) is applied as the kernel function of the SVR to estimate the optimal energy consumption of buildings. The performance of proposed optimizers is confirmed by simulation results. The SVR results are compared with the ANFIS, artificial neural network (ANN), and genetic programming (GP) results. The computational results show that an improvement in predictive accuracy and capability of generalization can be achieved by the ANFIS approach in comparison to the SVR estimation. Based on the simulation results, the effectiveness of the proposed optimization strategies is verified. The data used in soft computing were obtained from 180 simulations in EnergyPlus for variations of building envelope parameters.     

Landscape practice in the Middle East between local and global aspirations

In the Middle East today, there are strong tensions between global and local aspirations in landscape architectural projects. Modernism, introduced to major cities in the Middle East, led to design approaches that are detached from local context, some adopting a tabula rasa attitude to site or inspired by Western models with little adaptation. Ambitious designers who seek to celebrate local values through context-based designs face dilemmas between client-driven global aspirations and local contextual particularities. This perspective essay critically reviews landscape design approaches in the region against discourses of Modernism, regionalism and critical regionalism. Projects in Abu Dhabi, Dubai, Riyadh and Muscat were examined to provide a spectrum of current trends in landscape practices. Insights gained show that valuing intangible cultural meanings attached to landscapes, acknowledging particular ecological processes and working within the profound connections between culture and ecology, are critical to inform future design strategies.     

Fried egg digest decreases blood pressure in spontaneous hypertensive rats

Our previous study showed that in vitro simulated gastrointestinal digestion of fried whole egg (FWE) released several peptides with angiotensin converting enzyme-I (ACE-I) inhibitory properties. The present study evaluated in vivo blood pressure lowering effect of FWE digest in spontaneously hypertensive rats (SHR). Twelve to fourteen weeks old male SHRs were surgically implanted with telemetric blood pressure (BP) measuring devices. After one week recovery, animals were randomly allocated to three groups at dosage of FWE digest 0 (control), 100, and 1000 mg of FWE digest/kg body weight for 3 days (n = 8), and the BP was recorded continuously. The 1000 mg/kg BW group showed a significant decrease in BP and also rectified the impaired circadian blood pressure rhythm compared to the control group. This study indicates a potential blood pressure lowering effect of egg consumption.     

Kernel analysis on Grassmann manifolds for action recognition

Modelling video sequences by subspaces has recently shown promise for recognising human actions. Subspaces are able to accommodate the effects of various image variations and can capture the dynamic properties of actions. Subspaces form a non-Euclidean and curved Riemannian manifold known as a Grassmann manifold. Inference on manifold spaces usually is achieved by embedding the manifolds in higher dimensional Euclidean spaces. In this paper, we instead propose to embed the Grassmann manifolds into reproducing kernel Hilbert spaces and then tackle the problem of discriminant analysis on such manifolds. To achieve efficient machinery, we propose graph-based local discriminant analysis that utilises within-class and between-class similarity graphs to characterise intra-class compactness and inter-class separability, respectively. Experiments on KTH, UCF Sports, and Ballet datasets show that the proposed approach obtains marked improvements in discrimination accuracy in comparison to several state-of-the-art methods, such as the kernel version of affine hull image-set distance, tensor canonical correlation analysis, spatial-temporal words and hierarchy of discriminative space-time neighbourhood features.     

A Taguchi approach production of spray-dried whey powder enriched with nanoencapsulated vitamin D3

Abstract

The objective of the present study was to investigate the effect of inlet air temperature of spray drying and different combinations of carrier agents (maltodextrin (MD), gum Arabic (GA), modified starch (MS), and whey protein concentrate (WPC)) on the physicochemical characteristics of spray-dried whey powder, enriched with vitamin D₃ to improve its usage as a functional ingredient. Firstly, vitamin D₃ was nanoencapsulated by nanoliposome prepared with egg yolk lecithin, sesame oil, and glycerol through thin-film dispersion method. The mean particle size of prepared nanoliposomes was 140?nm. Then, the prepared nanocarriers loaded with vitamin D₃ were added into the feed solution and dried through spray dryer. The effect of carrier agent types and inlet air temperature on the physicochemical (moisture content, solubility, porosity, color, and powder yield) and microstructure properties of obtained spray-dried powders were investigated. The optimal carrier agents and condition of spray drying were selected by Taguchi design. Our results showed that the inlet air temperature and carrier agent had significant effects on the characterization of powders. Powders produced by 2% WPC, 3% MS, and 25% MD at 170?°C inlet air temperature showed the highest powder yield (96.4%). Also, the morphology of powders was affected by carrier agent types; increase in MD concentration in feed solution causes to create smoother and spherical spray-dried powder particles.     

Adsorptive separation of La(III) from aqueous solution via the synthesized [Zn(bim)2(bdc)]n metal-organic framework

Lanthanum is one of the rare earth metals which due to specific chemio-physical properties, has wide applications in different industries. In this research, the ability of the synthesized metal-organic framework (MOF), [Zn(bim)₂(bdc)]_n (ZBB) for the removal of lanthanum ions from the aqueous stream was investigated in the batch and column processes. The synthesized MOF was characterized by using scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The effect of pH on lanthanum ions adsorption was evaluated in the range from 1 to 7. Moreover, isothermal, kinetic, and thermodynamic parameters for adsorption of La(III) ions onto the synthesized MOF were evaluated. The adsorption capacity of lanthanum ions onto the synthesized MOF was calculated to be about 130 mg/g. Thermodynamic studies demonstrate the endothermic and chemical nature of lanthanum adsorption, while kinetic studies suggest the pseudo-first-order of reaction. In column mode, the effect of solution flow rate passing through the fixed-bed was studied. Experimental data confirm that increasing the bed flow rate causes a decrease in the adsorption capacity of lanthanum ions on the synthesized MOF.     

Co-Stimulation of Oxytocin and Arginine-Vasopressin Receptors Affect Hypothalamic Neurospheroid Size

Oxytocin (OXT) is a neuropeptide involved in a plethora of behavioral and physiological processes. However, there is a prominent lack of 3D cell culture models that investigate the effects of OXT on a cellular/molecular level. In this study, we established a hypothalamic neuronal spheroid model to investigate the cellular response in a more realistic 3D setting. Our data indicate that the formation of spheroids itself does not alter the basic characteristics of the cell line and that markers of cellular morphology and connectivity are stably expressed. We found that both OXT and arginine vasopressin (AVP) treatment increase spheroid size (surface area and volume), as well as individual nucleus size, which serves as an indicator for cellular proliferation. The cellular response to both OXT and AVP seems mainly to be mediated by the AVP receptor 1a (V1aR); however, the OXT receptor (OXTR) contributes significantly to the observed proliferative effect. When we blocked the OXTR pharmacologically or knocked down the OXTR by siRNA, the OXT- or AVP-induced cellular proliferation decreased. In summary, we established a 3D cell culture model of the neuronal response to OXT and AVP and found that spheroids react to the treatment via their respective receptors but also via cross-talk between the two receptor types.     

ContainerCloudSim: An environment for modeling and simulation of containers in cloud data centers

Containers are increasingly gaining popularity and becoming one of the major deployment models in cloud environments. To evaluate the performance of scheduling and allocation policies in containerized cloud data centers, there is a need for evaluation environments that support scalable and repeatable experiments. Simulation techniques provide repeatable and controllable environments, and hence, they serve as a powerful tool for such purpose. This paper introduces ContainerCloudSim, which provides support for modeling and simulation of containerized cloud computing environments. We developed a simulation architecture for containerized clouds and implemented it as an extension of CloudSim. We described a number of use cases to demonstrate how one can plug in and compare their container scheduling and provisioning policies in terms of energy efficiency and SLA compliance. Our system is highly scalable as it supports simulation of large number of containers, given that there are more containers than virtual machines in a data center. Copyright © 2016 John Wiley & Sons, Ltd.