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This paper describes and proves the consistency of a flexible numerical method for producing solutions to state and control constrained control problems with parameter dependencies. This method allows for the use of a variety of underlying discretisation schemes, which can be catered to differing numerical challenges of specific problems, such as rapid convergence or large parameter spaces. The paper first provides a broad formulation for optimal control problems with parameter dependencies which includes multiple types of state, control, and end time constraints to enable a wide scope of application. For this formulation, the consistency of these methods for state and control constrained problems is then proved. Finally, a numerical example of an optimal search problem with constraints is demonstrated.

This paper introduces a new concept of partial observability for nonlinear systems. This new approach enables a quantitative analysis on the observability of an individual state variable and unknown parameters of a nonlinear dynamics even when the system is not observable in the traditional sense. The paper develops theoretical properties of partial observability and its computational algorithms. These results are applied and validated on a nonstandard estimation problem of detecting the internal cooperating strategy of a particular adversarial swarm model. Partial observability analysis on the parameters that define the cooperating strategy reveals interesting findings. For example, some parameters are observable even when the swarm is at a steady state that is not observable in traditional sense. It is also shown that observability of the internal cooperating strategy depends on both the swarm trajectory and the time window of the measurement. Motivated by these findings, a variational method of estimation based on the dynamic optimization of a cost function is proposed. Simulation results show that the proposed estimation method outperforms Kalman filters. The results in this paper provide useful tools for applications involving adversarial swarms, including defense against swarm attacks and herding of biological swarms.

This second paper presents an in-depth analysis of the composition of the planetary material that has been accreted on to seven white dwarfs with circumstellar dust and gas emission discs with abundances reported in Rogers et al. The white dwarfs are accreting planetary bodies with a wide range of oxygen, carbon, and sulphur volatile contents, including one white dwarf that shows the most enhanced sulphur abundance seen to date. Three white dwarfs show tentative evidence (2–3 |$\sigma$|⁠) of accreting oxygen-rich material, potentially from water-rich bodies, whilst two others are accreting dry, rocky material. One white dwarf is accreting a mantle-rich fragment of a larger differentiated body, whilst two white dwarfs show an enhancement in their iron abundance and could be accreting core-rich fragments. Whilst most planetary material accreted by white dwarfs display chondritic or bulk Earth-like compositions, these observations demonstrate that core-mantle differentiation, disruptive collisions, and the accretion of core-mantle differentiated material are important. Less than 1 per cent of polluted white dwarfs host both observable circumstellar gas and dust. It is unknown whether these systems are experiencing an early phase in the disruption and accretion of planetary bodies, or alternatively if they are accreting larger planetary bodies. From this work there is no substantial evidence for significant differences in the accreted refractory abundance ratios for those white dwarfs with or without circumstellar gas, but there is tentative evidence for those with circumstellar gas discs to be accreting more water rich material which may suggest that volatiles accrete earlier in a gas-rich phase. [ABSTRACT FROM AUTHOR]

Enhancing food security is one of the United Nations Sustainable Development Goals. Improved agricultural production is an approach to addressing food insecurity. However, these efforts can result in significant changes that are associated with increased risk of non-communicable chronic diseases. Previous research with women in Central Kenya found that the number of years a woman-farmer was engaged in dairy development was associated with greater food security and energy (kJ) intake. No studies have examined food security and the nutrition transition among rural farm women involved in dairy development initiatives. A cross-sectional survey was conducted in 2009 and again in 2017. Chain referral sampling was used in 2009 to recruit 111 women in five groups based on how long they had been a dairy group member (non-members and members from one to more than 10 years). In 2017, 20 women were randomly selected from 85 of the dairy-group member households surveyed in 2009 and a comparison group of 20 women was randomly selected from a list that was generated by referral from the participants. In person one-on-one interviews were conducted with a translator. Demographic, household food security, and dietary intake were collected in both years. In 2009 women's height and weight data were collected for BMI calculation. Associations among food security, BMI, dietary intake, and year of data collection were examined. Demographic characteristics were comparable between 2009 and 2017 and between food secure and food insecure households. In both years, the majority of households were categorized as not food insecure (67% and 75%; 2009 and 2017, respectively). In 2009 almost half the women (49.4%) had BMIs in the overweight and obese category. Food secure women had a significantly higher median BMI (26.5) compared with food insecure women (24.0). Diet diversity was low ([less than or equal to]5) for all women and there was little evidence for a classic 'western diet' of the nutrition transition. There was evidence of globalization in food availability and greater purchasing capacity that was demonstrated by the high proportion of women that consumed sugar, refined fats and oils, refined maize and wheat flours, and bread. Household food security was associated with the consumption of sugar, cabbage, wheat flour and bread. These findings support a unique rural nutrition transition, with food security, characterized by low dietary diversity, access to refined basic foods and high unhealthy BMI. Governments and non-governmental organizations need to support nutrition-sensitive agriculture and public health programs to curb the crisis of overweight, undernourishment and chronic diseases. Key words: agriculture, nutrition transition, rural, farm, Kenya, women, BMI, diet diversity, BACKGROUND Enhancing food security is a key element of the United Nations Sustainable Development Goal of ending hunger [1]. Improved agricultural production is one approach to addressing food insecurity, poverty [...]

This paper focuses on a non-standard constrained nonlinear optimal control problem in which the objective functional involves an integration over a space of stochastic parameters as well as an integration over the time domain. The research is inspired by the problem of optimizing the trajectories of multiple searchers attempting to detect non-evading moving targets. In this paper, we propose a framework based on the approximation of the integral in the parameter space for the considered uncertain optimal control problem. The framework is proved to produce a zeroth-order consistent approximation in the sense that accumulation points of a sequence of optimal solutions to the approximate problem are optimal solutions of the original problem. In addition, we demonstrate the convergence of the corresponding adjoint variables. The accumulation points of a sequence of optimal state-adjoint pairs for the approximate problem satisfy a necessary condition of Pontryagin Minimum Principle type, which facilitates assessment of the optimality of numerical solutions.

Data underlying the findings described in this manuscript may be obtained in accordance with AstraZeneca's data sharing policy described at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure. Lack of effect of benralizumab on signs and symptoms of moderate-to-severe atopic dermatitis: Results from the phase 2 randomized, double-blind, placebo-controlled HILLIER trial Ninety-six patients (including 26 adolescents) and 98 patients (27 adolescents) were randomized into the benralizumab and placebo groups, respectively. [Extracted from the article]

ABSTRACT [ILLUSTRATION OMITTED] The typical high-starch, low diversity diet in developing countries is associated with undernutrition, morbidity and mortality. Previous research with households in Mukurwe-ini Division (Central Kenya) found that [...]