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Nonparametric Estimation of the Conditional Distribution Function For Surrogate Data by the Regression Model
Get PDFThe main objective of this paper is to estimate the conditional cumulative distribution using the nonparametric kernel method for a surrogated scalar response variable given a functional random one. We introduce the new kernel type estimator for the conditional cumulative distribution function (cond-cdf) of this kind of data. Afterward, we estimate the quantile by inverting this estimated cond-cdf and state the asymptotic properties. The uniform almost complete convergence (with rate) of the kernel estimate of this model and the quantile estimator is established. Finally, a simulation study completed to show how our methodology can be adopted
A High Order Finite Difference Method to Solve the Steady State Navier-Stokes Equations
Get PDFIn this article, we develop a fourth order finite difference method to solve the system of steady state Navier-Stokes equations and apply it to the benchmark problem known as the square cavity flow problem. The numerical results of -velocity components and -velocity components obtained at the center of the cavity are compared with the results obtained by the method developed by Greenspan and Casulli to solve the time dependent system of Navier-Stokes equations. The method described in this article is easy to implement and it has been shown to be more efficient and stable than the method by Greenspan and Casulli. Present method converges for a range of various viscosity coefficients for which the method of Greenspan and Casulli is not stable. We have included the contour plots of horizontal velocity () components and vertical velocity () components to facilitate the understanding of the steady state flow inside the cavity
Energy stored and capacitance of a circular parallel plate nanocapacitor
No full textNanocapacitors have received a great deal of attention in recent years due to the promises of high energy storage density as device scaling continues unabated in the nanoscale era. High energy storage capacity is a key ingredient for many nanoelectronic applications in which the significant consumption of energy is required. The electric properties of a nanocapacitor can be strongly modified from the expected bulk properties due to finite-size effects which means that there is an increased need for the accurate characterization of its properties. In this work, we considered a theoretical model for a circular parallel plate nanocapacitor and calculated exactly, in closed analytic form, the electrostatic energy stored in the nanocapacitor as a function of the size of the circular plates and inter-plate separation. The exact expression for the energy is used to derive an analytic formula for the geometric capacitance of this nanocapacitor. The results obtained can be readily amended to incorporate the effects of a dielectric thin film filling the space between the circular plates of the nanocapacitor
Risk and Protective Markers for Well-Being in Latinx Immigrants in Removal Proceedings
No full textObjectives: There are currently 1,308,327 immigrants in removal proceedings, over 80% of whom are Latinx (TRAC, 2021b). This study examined the relation among putative protective markers (i.e. social support, religious support, and legal support) and the emotional and physical well-being of Latinx individuals facing removal proceedings. Hypotheses: We hypothesized that increased social support, religious support, and legal support would buffer the negative relations between hopelessness, poor self-efficacy, and well-being measures (depression, anxiety, stress, mental well-being, somatic symptoms, and physical well-being). Method: Participants (N = 157; 31.2% men, M age = 33.4 years) had an active immigration court case in Texas and completed a demographic questionnaire, the Beck Hopelessness Scale, General Self-Efficacy Scale, Multidimensional Scale of Perceived Social Support, Multi-Faith Religious Support Scale, Depression, Anxiety, Stress Scale-21, Patient Health Questionnaire-15, and Short Form Health Survey-12. Results: Higher levels of hopelessness and poor self-efficacy were associated with more negative well-being outcomes, while social support was associated with more positive well-being outcomes. Contrary to hypotheses, religious support and legal support served as risk markers independently, while legal support interacted with hopelessness, such that decreased legal support was associated with higher mental well-being at lower levels of hopelessness and interacted with poor self-efficacy, such that increased legal support was associated with poorer mental well-being at lower levels of self-efficacy. All effect sizes were small (rsp2 =.04 to.16). Conclusions: Targeting hopelessness and poor self-efficacy while promoting social support may help mental health professionals improve the well-being of immigrants in removal proceedings
Impact of interfacial barriers onthe oxidative stability of lipophilicbioactive compounds in oil-in-wateremulsions - The case of lutein
No full textOils, which consist of fatty acids (FA), are dispersed in the aqueous phase of food emulsions. Under food processing conditions (e.g., high heat, shear forces), and in the presence of oxygen, polyunsaturated fatty acids (PUFA) may become oxidized. It is generally accepted that the interfacial region, which is the contact region between the oil phase and the aqueous phase, represents a critical area in the emulsion system with regard to the development of oxidation. A better understanding of the relationship between the interfacial region (oil droplet size) and interfacial composition (emulsifier type) may allow the creation of stable food emulsions against oxidation. Emulsifiers work by stabilizing oils suspended in water, and this is achieved electrostatically. A part of an emulsifier is attracted to water while its other part is attracted to the oil. The effects of emulsifiers in limiting the transport of free radicals across the emulsion interface and its impact on the oxidative stability of lipophilic bioactive compounds is an area of active research. The transport of free radicals across the emulsion interface can be measured using a peroxide method. The free radicals are generated in the aqueous phase using 2,2\u27-azobis (2-amidinopropane) dihydrochloride (AAPH). The peroxide method can reveal the barrier properties of emulsifiers towards a water-soluble radical initiator (AAPH) in emulsion systems. Lutein, a xanthophyll carotenoid, was selected as a lipophilic bioactive compound (phytonutrient) model to evaluate the interfacial barrier properties of emulsifiers in an emulsion-based delivery system prepared with corn oil, which is high in PUFA. The lutein-loaded emulsions were formulated with the following emulsifiers: bovine casein; caprine casein (αs1-I); and caprine casein (as1-II). The peroxide value (PV) demonstrated that lutein-loaded emulsions stabilized with caprine casein (αs1-II) provided a significantly (p \u3c 0.05) enhanced interfacial barrier limiting the transport of peroxyl radicals across the oil-water interface. In agreement with PV measurements, chemical (color) stability results showed that lutein was most stable (p\u3c0.05) under the photo-oxidative conditions when emulsions were stabilized by caprine casein (αs1-II). The better interfacial barrier properties exhibited by caprine casein (αs1-II) can be used to create lutein-loaded emulsion formulations with improved chemical (color) stability for food and beverage applications.
Potential role of technology innovation in transformation of sustainable food systems: A review
No full textAdvanced technologies and innovation are essential for promoting sustainable food systems (SFSs) because these technologies can be used to answer some of the critical questions needed to transform SFSs and help us better understand global food security and nutrition. The main ob-jective of this study is to address the question of whether technological innovations have an impact on the transformation of SFSs. There are certain innovations including agricultural land utilization, food processing, production systems, improvement in diets according to people’s needs, and management of waste products. This study provides an overview of new technologies and innovations being used with potential to transform SFSs. Applications of emerging technologies in digital agri-culture, including the Internet of Things (IoT), artificial intelligence and machine learning, drones, use of new physical systems (e.g., advanced robotics, autonomous vehicles, advanced materials), and gene technology (e.g., biofortified crops, genome-wide selection, genome editing), are dis-cussed in this study. Additionally, we suggest eight action initiatives, which are transforming mind-sets, enabling social licensing, changing policies and regulations, designing market incentives, safe-guarding against undesirable effects, ensuring stable finance, building trust, and developing transition pathways that can hasten the transition to more SFSs. We conclude that appropriate incen-tives, regulations, and social permits play a critical role in enhancing the adoption of modern technologies to promote SFSs
An integrated approach to estimate surface soil moisture in agricultural lands
No full textSentinel-1 and Landsat-8 data were used to retrieve soil moisture from top soil surface (0–5 cm depth) at agricultural land (area under wheat crop). After pre-processing of satellite data and removal of vegetation influence (σ°veg) using Water Cloud Model (WCM), total backscattering coefficient (σ°total) and Normalized Difference Vegetation Index (NDVI) were used to simulate backscattering from soil (σ°soil). Modified Dubois Model (MDM) and Topp\u27s Model were used to retrieve soil moisture using ε. Further, modelled soil moisture was evaluated using in situ soil moisture measurements and a Time Domain Reflectometer during Sentinel-1 overpass (24 January, 25 February and 13 March 2018). Statistical tests showed that an integrated approach has potential to improve soil moisture estimates over the vegetated/cropped area for agricultural and hydrological studies
Biowastes of slaughterhouses and wet markets: an overview of waste management for disease prevention
No full textSlaughterhouse and wet market wastes are pollutants that have been always neglected by society. According to the Food and Agriculture Organization of the United Nations, more than three billion and nineteen million livestock were consumed worldwide in 2018, which reflects the vast amount and the broad spectrum of the biowastes generated. Slaughterhouse biowastes are a significant volume of biohazards that poses a high risk of contamination to the environment, an outbreak of diseases, and insecure food safety. This work comprehensively reviewed existing biowaste disposal practices and revealed the limitations of technological advancements to eradicate the threat of possible harmful infectious agents from these wastes. Policies, including strict supervision and uniform minimum hygienic regulations at all raw food processing factories, should therefore be tightened to ensure the protection of the food supply. The vast quantity of biowastes also offers a zero-waste potential for a circular economy, but the incorporation of biowaste recycling, including composting, anaerobic digestion, and thermal treatment, nevertheless remains challenging
Some Asymptotic Properties of Conditional Density Function for Functional Data Under Random Censorship
Get PDFIn this work, we investigate the asymptotic properties of a nonparametric mode of a conditional density when the real response variable is censored and the explanatory variable is valued in a semi- metric space under ergodic data. First of all, we establish asymptotic properties for a conditional density estimator from which we derive an central limit theorem (CLT) of the conditional mode estimator. Simulation study is also presented to illustrate the validity and finite sample performance of the considered estimator
Global Stability of Generalized Within-host Chikungunya Virus Dynamics Models
Get PDFThis paper proposes two models of a general nonlinear within-host Chikungunya virus (CHIKV) dynamics. The production, incidence, proliferation and removal rates of all compartments are modeled by general nonlinear functions that satisfy a set of reasonable conditions. The second model takes into consideration two forms of infected host cells: (i) latently infected cells which do not produce the CHIKV, (ii) actively infected cells which generate the CHIKV particles. We show that all the solutions of the models are nonnegative and bounded. The global stability of the steady states of the models is proven by applying Lyapunov method and LaSalle’s invariance principle. We perform numerical simulations to complement the obtained theoretical results