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Poor diets are a leading cause of morbidity and mortality. Exposure to low-quality food environments saturated with fast food outlets is hypothesized to negatively impact diet. However, food environment research has predominantly focused on static food environments around home neighborhoods and generated mixed findings. In this work, we leverage population-scale mobility data in the U.S. to examine 62M people's visits to food outlets and evaluate how food choice is influenced by the food environments people are exposed to as they move through their daily routines. We find that a 10% increase in exposure to fast food outlets in mobile environments increases individuals' odds of visitation by 20%. Using our results, we simulate multiple policy strategies for intervening on food environments to reduce fast-food outlet visits. This analysis suggests that optimal interventions are informed by spatial, temporal, and behavioral features and could have 2x to 4x larger effect than traditional interventions focused on home food environments. Using large-scale mobility data, the authors examine how the quality of food in mobile environments away from home affects food choice. [ABSTRACT FROM AUTHOR]

What predicts a neighborhood's adaptability to essential public health policies and shelter-in-place regulations that prevent the harmful spread of COVID-19? To answer this question, we present a novel application of human mobility patterns and human behavior in a network setting. We analyze 2 years of mobility data (January 2019 to December 2020) from New York City and construct weekly mobility networks between census block groups based on aggregated point-of-interest visit patterns. Our results indicate that neighborhoods' socioeconomic and geographic characteristics play a significant role in predicting their adaptability to active shelter-in-place policies. Our simulation outcomes reveal that, alongside factors such as race, education, and income, the geographical attributes of neighborhoods, such as access to amenities that satisfy community needs are equally important factors in predicting neighborhood adaptability to public health policies. These findings offer valuable insights that can enhance urban planning strategies, thereby aiding pandemic mitigation efforts and fostering increased adaptability of urban areas in the face of exogenous shocks like the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

The characteristics of food environments people are exposed to, such as the density of fast food (FF) outlets, can impact their diet and risk for diet-related chronic disease. Previous studies examining the relationship between food environments and nutritional health have produced mixed findings, potentially due to the predominant focus on static food environments around people's homes. As smartphone ownership increases, large-scale data on human mobility (i.e., smartphone geolocations) represents a promising resource for studying dynamic food environments that people have access to and visit as they move throughout their day. This study investigates whether mobility data provides meaningful indicators of diet, measured as FF intake, and diet-related disease, evaluating its usefulness for food environment research. Using a mobility dataset consisting of 14.5 million visits to geolocated food outlets in Los Angeles County (LAC) across a representative sample of 243,644 anonymous and opted-in adult smartphone users in LAC, we construct measures of visits to FF outlets aggregated over users living in neighborhood. We find that the aggregated measures strongly and significantly correspond to self-reported FF intake, obesity, and diabetes in a diverse, representative sample of 8,036 LAC adults included in a population health survey carried out by the LAC Department of Public Health. Visits to FF outlets were a better predictor of individuals' obesity and diabetes than their self-reported FF intake, controlling for other known risks. These findings suggest mobility data represents a valid tool to study people's use of dynamic food environments and links to diet and health. [ABSTRACT FROM AUTHOR]

Using the finite difference method in the time domain, the present study deals with the effect of the presence of aluminum and gold nanorods on the quantities of the short-circuit current density and the absorption in the ITO/PEDOT:PSS/P3HT:PCBM/ZnO/Al organic solar cell. The nanorods, made of an aluminum cylinder and two golden caps, are located in a hexagonal pattern inside the P3HT:‌PCBM layer and at the border with ZnO. During the simulation, the standard spectral pattern of the sun AM1.5 has been used in the spectral range of 300–1200 nm. Calculations have shown that the presence of nanorods significantly improves the values of the aforementioned quantities. This is especially noticeable in the range of high wavelengths. According to the results, when the height of the nanoparticles changes, one can see changes in the optimal thickness of the highest short-circuit current density and the absorption in a way that the P3HT:PCBM active layer is optimal in thicknesses of 150, 200, and 250 nm at nanorod heights of 50, 100, and 150 nm, respectively. The calculations in different conditions show that the short-circuit current density and the absorption under the optimal thickness of the active layer is 150 nm, the height of the cylinder is 50 nm, the radius of the cylinder is 20 nm, and the curvature radius of both caps is 4 nm. [ABSTRACT FROM AUTHOR]

Small and Medium-sized Enterprises play a significant role in most economies by contributing to job creation and economic growth. A majority of such merchants rely on business financing, and thus, financial institutions and investors need to assess their performance before making decisions on business loans. However, current methods of predicting merchants' future performance involve their private internal information, such as revenue and customer base, which cannot be shared without potentially exposing critical information. To address this problem, we first propose a novel approach to predicting merchants' future performance using credit card transaction data. Specifically, we construct a merchant network, regarding customers as bridges between merchants, and extract features from the constructed network structure for prediction purposes. Our study results demonstrate that the performance of machine learning models with features extracted from our proposed network is comparable to those with conventional revenue- and customer-based features, while maintaining higher privacy levels when shared with third-party organizations. Our approach offers a practical solution to privacy concerns over data and information required for merchants' performance prediction, enabling safe data-sharing among financial institutions and investors, helping them make more informed decisions on allocating their financial resources while ensuring that merchants' sensitive information is kept confidential. [ABSTRACT FROM AUTHOR]

This paper puts forward a transient numerical model for thermoacoustic energy convertors using Rott's equations combined with electrical circuit analogy. To enhance the accuracy of model outcomes, the lumped element values are updated at each time step as a function of temperature. Accordingly, a nonlinear temperature distribution is obtained along the hot core. The developed numerical approach is in line with the experimental results of a standing wave thermoacoustic engine. Based on this method, the temperature variations along the stack and the impact of stack material on start-up time and onset temperature are numerically investigated. Additionally, the onset temperature profiles are calculated and presented comparatively for the numerical and experimental results. The start-up time of spontaneous oscillations is calculated for the standing wave system. Consequently, the best geometry that quickly reaches sustained oscillations can be selected using this model. Examining the temperature profile during the start-up and damping process highlights a temperature difference between these two processes. This is calculated as 35 K in the numerical solution and measured as 38 K in the experiment for a standing wave engine. Observations show that using a material with lower thermal conductivity in the stack section can reduce the onset-damping temperature difference. The novel approach described here shows potential in capturing the onset-damping behavior of thermoacoustic systems efficiently. [ABSTRACT FROM AUTHOR]

Much recent work has illuminated the growth, innovation, and prosperity of entire cities, but there is relatively less evidence concerning the growth and prosperity of individual neighborhoods. In this paper we show that diversity of amenities within a city neighborhood, computed from openly available points of interest on digital maps, accurately predicts human mobility ("flows") between city neighborhoods and that these flows accurately predict neighborhood economic productivity. Additionally, the diversity of consumption behaviour or the diversity of flows together with geographic centrality and population density accurately predicts neighborhood economic growth, even after controlling for standard factors such as population, etc. We develop our models using geo-located purchase data from Istanbul, and then validate the relationships using openly available data from Beijing and several U.S. cities. Our results suggest that the diversity of goods and services within a city neighborhood is the largest single factor driving both human mobility and economic growth. [ABSTRACT FROM AUTHOR]

Objective: Epilepsy is a common neurological disorder, the history of which dates back to thousands of years ago. Avicenna (980-1037 AD) is a famous Persian scholar who considered different types of epilepsy and their specific treatments. His book Al-Qanun fi al-Tibb was taught in Europe for several years. Along with explaining the diseases occurring in various body organs, the book describes neurological and neuropsychological conditions such as epilepsy METHODS: This article is a review of the book Al-Qanun fi al-Tibb and some of the traditional Persian medicine sources, including Kāmil al-Sināa al Tibbiya and Makhzan-O-L Advieh, on uterine epilepsy, its etiology, clinical manifestations and treatments. Also, articles related to this topic in the field of traditional Persian medicine or historical articles have been searched for in Google Scholar search engine or PubMed database.Results: Avicenna categorizes the causes of epilepsy into two main groups: those caused by brain diseases and those associated with the diseases of other organs. He believed that the stomach, the spleen, the maraqq, the uterus, or other body organs influence the brain and can cause epilepsy. In uterine epilepsy, the primary pathology lies with the uterus and can affect the brain. This condition occurs due to the retention of the menses or semen.Conclusion: In this historical article, we intend to explain Avicenna's viewpoint on uterine epilepsy. We suggest further studies on this topic, for example, to evaluate the frequency of epilepsy in patients with the retention of the menses or the semen. [ABSTRACT FROM AUTHOR]

There are studies that show that the concepts of epilepsy have been rooted in Persian medicine; Avicenna "Ibn-e-Sina"-one of the great Persian physicians in the Islamic golden age (9th-12th century AD)-has considered some types of epilepsy with the association of the stomach, the spleen, the "Maraqq," and the whole body which has not been reviewed properly. These organs influence on the brain and can cause epilepsy. This article presents concept of Maraqq-related epilepsy; according to Avicenna's view, "Maraqq" is a membranous structure which is located in the abdomen (equivalent of parietal peritoneum in current nomenclature). We discuss his viewpoint about the diagnosis and treatment of Maraqq-related epilepsy with focus on herbal remedies. The concept of a relationship between the "Maraqq" and the brain is well discussed in the old Persian medicine texts; however, it seems that further studies in this area are required to clarify Avicenna's view about the pathophysiological mechanisms, clinical manifestations, and treatment strategies. [ABSTRACT FROM AUTHOR]

Avicenna has introduced a type of headache and its related treatment called I uda al-Bu rani i (critical headache), in the I Fa l fi A naf a - uda al-Ka'in bi-l-Mosharakat i (section of types of participatory headaches) [[2]]. The critical stage of a disease named I Bu ran i (crisis) is the days in the course of some acute illnesses usually occurring in the climax of the disease that is accompanied by severe and sudden appearance of some symptoms and signs. [Extracted from the article]

One of the best remaining manuscripts is the "Canon of Medicine" fathered by Avicenna in the Islamic Golden Age [ninth to twelfth century AD]. Considering Avicenna's role in the development of medical science in the Islamic Golden Age, we reviewed Avicenna's point of view on sexual headache based on his famous book "Canon of Medicine". This historical review discusses the clinical approaches applied to diagnose, classify, and treat sexual headache-specifically herbal therapy-from the viewpoint of Avicenna and Traditional Persian Medicine. The accurate observations of Avicenna give a comprehensive classified etiology of the sexual headache. The efficacy of some medicinal herbs used by him for sexual headache treatments, such as the analgesic effect of lavender, chamomile, and jasmine has been proved by current medicine; however, the knowledge of medieval physicians should be scientifically investigated even further to extend new remedial options for sexual headache. [ABSTRACT FROM AUTHOR]

This paper presents vibration analysis of a circular piezoelectric micro-plate in fluidic environment. PVDF film is used as the piezoelectric material. PVDF is a material with asymmetric matrix of piezoelectric constants and shows different piezoelectric properties in different directions. The governing equations, which are more complicated compared to piezo-ceramics, are derived. The boundary conditions for the plate are assumed fully clamped at outer edge, as is the case in many micro devices. Liquid is modeled as a damping foundation under the plate. The equations of motion are solved using generalized differential quadrature method to obtain Eigen frequencies and mode shapes of the plate. The results are compared by developed finite element analysis. [ABSTRACT FROM AUTHOR]

Hole transport is numerically studied by means of the Monte Carlo method in a single blended layer of poly(9,9'-dihexyl fluorenyl-2,7-diyl) (PFO) and poly(2-methoxy-5-(2-ethylhexyloxy)-l,4-phenylenevinylene) (ME H-PPV), which is sandwiched between two electrodes. A bimodal Gaussian density of states is used for randomly distributed localized states in the blended organic layer and an exponential distribution function for trap density of states. In this study, a new approximation has been used for the Fermi level instead of the Boltzmann approximation due to the high charge carrier density. The current density and the mobility have been calculated for different concentrations of MEH-PPV versus voltage and 1000/T at temperatures 150-290 K. The results of calculations show that the current density and the mobility are maximized at the blending ratio of 2 wt%, and there is a linear relationship between the current density and 1000/T at different voltages. The comparison of the numerical results with the experimental data shows a very good consistency between them, particularly at low and medium voltages of the working range of organic semiconductor devices. [ABSTRACT FROM AUTHOR]

The Monte Carlo method has been used to simulate the average number of injected electrons and the related electric potential and field distributions in a single film of tris-(8-hydroxyquinoline) aluminum (Alq) and 8-hydroxyquinolinato lithium (Liq) blend which is sandwiched between two electrodes of Al. In our simulations, two correlated and uncorrelated states have been taken into account for the energy of the charge carriers which are located on a 3D simple cubic lattice of sites. The layer averaged number of charges is maximized near the injecting and collecting electrodes, and it decreases as the distance increases from the electrodes for the two states. Moreover, results show that the layer averaged number of charges is higher in pristine Alq, as compared to other materials in the study, but no change is observed in the width of space charge regions in the materials. The electric field distribution related to the electrons injected into the materials is non-uniform, and it has higher values near the electrodes than other places. The electric field distribution shows a nonlinear behavior when the concentration of Liq increases in the Alq host, although it moves towards a linear state, and the magnitude of electric field increases as the blending ratio decreases. [ABSTRACT FROM AUTHOR]

In the present paper, dynamic pull-in instability and free vibration characteristics of circular higher-order shear deformable nanoplates subjected to hydrostatic and electrostatic forces are studied including surface stress effect. For this purpose, Eringen's nonlocal elasticity continuum in conjunction with the Gurtin-Murdoch elasticity theory is incorporated into the classical higher-order shear deformation plate theory to develop size-dependent plate model able to consider both of small scale and surface stress effects. The non-classical governing differential equations are then discretized along with simply supported and clamped edge supports by employing generalized differential quadrature (GDQ) method. To evaluate the size-dependent pull-in voltage of nanoplates, the hydrostatic-electrostatic actuation is assumed to be calculated by neglecting the fringing field effects and utilizing the parallel plate approximation. It is demonstrated that the pull-in instability occurs at lower voltages for nanoplates with higher values of nonlocal parameters. Moreover, it is found that surface stress effect can increase or decrease the pull-in voltage of nanoplates which depends on the sign of surface elastic constants. [ABSTRACT FROM AUTHOR]

In the current paper, dynamic stability analysis of microbeams subjected to piezoelectric voltage is presented in which the microbeam is integrated with piezoelectric layers on the lower and upper surfaces. Both of the flutter and divergence instabilities of microbeams with clamped-clamped and clamped-free boundary conditions are predicted corresponding to various values of applied voltage. To take size effect into account, the classical Timoshenko beam theory in conjunction with strain gradient elasticity theory is utilized to develop nonclassical beam model containing three additional internal length scale parameters. By using Hamilton's principle, the higher-order governing differential equations and associated boundary conditions are derived. Afterward, generalized differential quadrature method is employed to discretize the size-dependent governing differential equations along with clamped-clamped and clamped-free end supports. The critical piezoelectric voltages corresponding to various values dimensionless length scale parameter are evaluated and compared with those predicted by the classical beam theory. It is revealed that in the case of clamped-free boundary conditions, the both of flutter and divergence instabilities occur. However, for the clamped-clamped microbeams, only divergence instability takes place. [ABSTRACT FROM AUTHOR]

In this study, friction stir welding (FSW) technique was employed for joining AZ31 magnesium plates. Since SiC particles had been injected along the joint line, AZ31/SiC nano-composite was developed in the stir zone (SZ). To find the optimum condition, FSW was conducted under the combination of three rotational and two traveling speeds. Microstructural investigations were carried out through optical and scanning electron microscopes. Onion ring structure consisting SiC-rich and SiC-free regions was observed in SZ. In addition, reasonable particle dispersion happened in the specimen friction stir welded (FSWed) at 800 rpm and 75 mm/min. Thanks to the SiC reinforcements, grain size reduced from 44 μm in base metal to 5 μm in the SZ. Compared to previous researches, microstructural evolution associated with reinforcement particles exerted positive effects on the mechanical properties of the joint. Meanwhile, fracture surfaces of tensile specimens were closely examined and an extreme correlation with ductility results was observed. As expected, on the other hand, composite joints exhibited superior hardnesses to the base metal. Despite indiscernible difference, the foregoing specimen showed the highest hardness. [ABSTRACT FROM AUTHOR]

Swimming microrobots can exhibit high levels of performance to move freely in the human body fluids to fulfill risky biomedical operations by mimicking microorganisms. Many researchers have proposed micro swimming methods for viscous flows based on flagellar motion. Here, a novel swimming microrobot inspired by ciliated microorganisms based on artificial cilia is introduced. The hydrodynamic model is developed and performance parameters such as propulsive force, propulsive velocity and efficiency of the microrobot are computed. The velocity and efficiency dependence on design parameters of microrobot is evaluated. The proposed micro swimming concept offers appropriate efficiency, thrust, speed and maneuverability. It is shown that the introduced swimming microrobot can reach a maximum speed 4.5 mm/s and efficiency of 40%. The proposed microrobot has the potential to be utilized in both viscous and turbulent body flows. [ABSTRACT FROM AUTHOR]

Micromachining of microelectromechanical systems such as other fabrication processes has inherent variation that leads to uncertain dimensional and material properties. In this paper, the effect of material and feature dimension uncertainties due to fabrication process on electrothermal microactuator tip deflection is investigated. A simple and efficient uncertainty analysis method is used based on direct linearization method (DLM); uncertainty analysis is performed by creating second-order metamodel through Box-Behnken design and Monte Carlo simulation. The standard deviations of tip deflection obtained by these two probabilistic methods are very close. Simulation results have been validated by a comparison with experimental results in literature. Experimental results fall within 95% confidence boundary obtained by DLM method. Also, sensitivity analysis of microactuator has been explored; the results show that microactuator performance has been affected more by thermal expansion coefficient and microactuator gap uncertainties. [ABSTRACT FROM AUTHOR]

The present work deals with the study of the plasmonic modes of core–shell nanostructures (silver–aluminum nanocylinders) using the finite-difference time-domain (FDTD) numerical method. The nanocylinders are placed in a two-dimensional square periodic array under normal radiation in the spectral range of 200–800 nm. This study has tried to reduce radiation losses and create strong surface lattice resonances (SLR) in the ultraviolet (UV) region by using a suitable combination of materials and nanostructures. In this regard, it is demonstrated that by changing the dimensions and geometry of the cores of nanocylinders, as well as the characteristics of incident light radiation, one can obtain a suitable optical response in the near-UV spectral region. The calculations show that a new SLR peak related to the hybrid nanostructure is formed in the near-UV region under s-polarized radiation, and for the core with a circular cross-section, in addition to the primary modes related to an array composed of individual nanoparticles. This peak, with a quality factor of 41 at the wavelength of 372 nm, is close to the diffraction modes of the dielectric substrate. Also, by reducing the height of the core, another peak is formed with a quality factor of 12 at the wavelength of 260 nm under the shell’s plasmonic effects and close to the environment’s diffraction modes. These modes (SLRs) provide the possibility of achieving high-energy spectral regions with a suitable quality factor, which is not usually possible in other nanostructures. By changing the polarization of the incident light to p-polarization, depending on the period of the array, the principle resonance peak is formed with a shift to higher wavelengths in the visible region with a quality factor of 20 at the wavelength of 452 nm, as compared to s-polarization. This demonstrates the different spectral responses of nanocylinders under the influence of changes in the polarization of the incident light. The effects of the refractive index of the substrate on the plasmonic modes are also studied. The results indicate that the location and intensity of the core–shell modes (372 and 260 nm) are highly dependent on the substrate refractive index. The findings of the present study suggest the use of nanocylinders (core–shell) as a suitable option for application in sensors, nanolasers, and other optoelectronic devices. [ABSTRACT FROM AUTHOR]