Fully Probabilistic Design for Stochastic Discrete System with Multiplicative Noise

In this paper, a novel algorithm based on fully probabilistic design (FPD) is proposed for a class of linear stochastic dynamic processes with multiplicative noise. Compared with the traditional FPD, the new procedure is presented to deal with multiplicative noise and the system parameters are estimated online using linear optimisation methods. The performance index is characterised by the Kullback-Leibler divergence (KLD) distance. The generalised probabilistic control law is obtained by solving a generalised Riccatti equation that takes the multiplicative noise into consideration. To demonstrate the effectiveness of the proposed method, a numerical example is given and the results are compared with the traditional FPD

Fully probabilistic control for uncertain nonlinear stochastic systems

This paper develops a novel probabilistic framework for stochastic nonlinear and uncertain control problems. The proposed framework exploits the Kullback–Leibler divergence to measure the divergence between the distribution of the closed-loop behavior of a dynamical system and a predefined ideal distribution. To facilitate the derivation of the analytic solution of the randomized controllers for nonlinear systems, transformation methods are applied such that the dynamics of the controlled system becomes affine in the state and control input. Additionally, knowledge of uncertainty is taken into consideration in the derivation of the randomized controller. The derived analytic solution of the randomized controller is shown to be obtained from a generalized state-dependent Riccati solution that takes into consideration the state-and control-dependent functional uncertainty of the controlled system. The pro-posed framework is demonstrated on an inverted pendulum on a cart problem, and the results are obtaine

Consensus, Control and Message Passing in Complex Control Systems

Real-world merging systems are characterised by several challenges and high level of complexities, such as stochasticity, nonlinearities, high dimensionality, and systems with coupling. The aim of this thesis is to address these inconveniences in order to develop robust control algorithms for such real engineered emergent systems. The study in this thesis considered the development of the fully probabilistic (FP) framework that addresses the main challenge of controlling real-world stochastic and uncertain systems.The probabilistic framework characterises the dynamics of the system to be controlled in terms of probability distributions which is a desirable approach to handle the stochasticity of dynamical systems. Non-linearity of real-world systems on the other hand, hinders the derivation of analytic control solutions, yielding expensive numerical computations. To address this problem, a transformation method has been introduced to the developed FP control framework which facilitated the derivation of an analytic solution despite the nonlinearity of the system dynamics. This method transformed the nonlinear state function to another variant where the nonlinearities are preserved but have now been transformed to a nonlinear affine state function. The inclusion of this novelty allows for the control of more realistic systems which tend to be nonlinear. Further advancement includes the extension of the developed nonlinear FP control method to control large-scale complex nonlinear systems. This is achieved by decomposing the complex system into small subsystems and then decentrally controlling each individual subsystem by a local controller. Probabilistic message passing is thereafter used to coordinate between the subsystems constituting the complex system, thus achieving the overall objective of the controlled complex system. This decentralised control framework has further been advanced to consider several control objectives, including regulation, tracking and formation control where the subsystems that constitute the overall network rely on the probabilistic message passing approach to interact with each other

Additively Manufactured High-Strength Aluminum Alloys: A Review

This chapter summarizes the recent advances in additive manufacturing of high-strength aluminum alloys, the challenges of printability, and defects in their builds. It further intends to provide an overview of the state of the art by outlining potential strategies for the fabrication of bulk products using these alloys without cracking. These strategies include identifying a suitable processing window of additive manufacturing using metallic powders of conventional high-strength aluminum alloys, pre-alloying the powders, and developing advanced aluminum-based composites with reinforcements introduced either by in situ or ex situ methods. The resulting microstructures and the relationship between these alloys’ microstructure and mechanical properties have been discussed. Since post-processing is inevitable in several critical applications, the chapter concludes with a brief account of post-manufacturing heat treatment processes of additively manufactured aluminum alloys

To reach the poor: results from the ISNAR-IFPRI Next Harvest study on genetically modified crops, public research, and policy implications

"Local farming communities throughout the world face productivity constraints, environmental concerns, and diverse nutritional needs. Developing countries address these challenges in a number of ways. One way is public research that produces genetically modified (GM) crops and recognize biotechnology as a part of the solution. To reach these communities, GM crops, after receiving biosafety agreement, must be approved for evaluation under local conditions. However, gaps between approvals in the developed and developing world grow larger, as the process of advancing GM crops in developing countries becomes increasingly difficult. In several countries, only insect resistant cotton has successfully moved from small, confined experimental trials to larger, open trials and to farms. By far, most GM crop approvals have been for commercial products that perform well under tropical conditions. However, complete information on public GM crop research in developing countries has not been assessed. “Will policies and research institutions in the developing world stimulate the safe use of publicly funded GM food crops?” The relatively few GM crops approved from public research, coupled with growing regulatory, biosafety capacity, trade, and political concerns, argue to the contrary. To tackle this issue, we identified and analyzed public research pipelines for GM crops among 16 developing countries and transition economies. Respondents reported 209 genetic transformation events for 46 different crops at the time when the survey was conducted. The pipelines demonstrate scientific progress among publicly funded crop research institutes in participating countries. Information and findings are presented for GM crops nearing final stages of selection. Additional details are provided for the types of genes and traits used, the breadth of genetic resources documented, implications for regulation, and the type of research partnerships employed. Regulations, GM crop approvals, choice of transgene, and policy implications are discussed as they affect this research. Based on these findings, recommendations are presented that would help sustain and increase efficiency of publicly supported research while meeting biosafety requirements. To do so, the study examines results concerning investments and choices made in research, capacity, and policy development for biotechnology. These indicate the risk and potential for GM technologies in developing countries. Policy makers, those funding biotechnology, and other stakeholders can use this information to prioritize investments, consider product advancement, and assess relative magnitude of potential risks, and benefits." Authors' Abstract

Interface Modification for Energy Levels Alignment and Charge Extraction in CsPbI3_3 Perovskite Solar Cells

In perovskite solar cells (PSCs) energy levels alignment and charge extraction at the interfaces are the essential factors directly affecting the device performance. In this work, we present a modified interface between all-inorganic CsPbI$_3$ perovskite and its hole selective contact (Spiro-OMeTAD), realized by a dipole molecule trioctylphosphine oxide (TOPO), to align the energy levels. On a passivated perovskite film, by n-Octyl ammonium Iodide (OAI), we created an upward surface band-bending at the interface by TOPO treatment. This improved interface by the dipole molecule induces a better energy level alignment and enhances the charge extraction of holes from the perovskite layer to the hole transport material. Consequently, a Voc of 1.2 V and high-power conversion efficiency (PCE) of over 19% were achieved for inorganic CsPbI$_3$ perovskite solar cells. Further, to demonstrate the effect of the TOPO dipole molecule, we present a layer-by-layer charge extraction study by transient surface photovoltage technique (trSPV) accomplished by charge transport simulation.Comment: 20 pages, 4 Figure

Maternal time investment in caregiving activities to promote early childhood development: evidence from rural India

INTRODUCTION: Intervention strategies that seek to improve early childhood development outcomes are often targeted at the primary caregivers of children, usually mothers. The interventions require mothers to assimilate new information and then act upon it by allocating sufficient physical resources and time to adopt and perform development promoting behaviours. However, women face many competing demands on their resources and time, returning to familiar habits and behaviours. In this study, we explore mothers' allocation of time for caregiving activities for children under the age of 2, nested within a cluster randomised controlled trial of a nutrition and care for development intervention in rural Haryana, India. METHODS: We collected quantitative maternal time use data at two time points in rural Haryana, India, using a bespoke survey instrument. Data were collected from 704 mothers when their child was 12 months old, and 603 mothers when their child was 18 months old. We tested for significant differences in time spent by mothers on different activities when children are 12 months of age vs. 18 months of age between arms as well as over time, using linear regression. As these data were collected within a randomised controlled trial, we adjusted for clusters using random effects when testing for significant differences between the two time points. RESULTS: At both time points, no statistically significant difference in maternal time use was found between arms. On average, mothers spent most of their waking time on household chores (over 6 h and 30 min) at both time points. When children were aged 12 months, approximately three and a half hours were spent on childcare activities for children under the age of 2 years. When children were 18 months old, mothers spent more time on income generating activities (30 min) than when the children were 12 years old, and on leisure (approximately 4 h and 30 min). When children were 18 months old, less time was spent on feeding/breastfeeding children (30 min less) and playing with children (15 min). However, mothers spent more time talking or reading to children at 18 months than at 12 months. CONCLUSION: We find that within a relatively short period of time in early childhood, maternal (or caregiver) time use can change, with time allocation being diverted away from childcare activities to others. This suggests that changing maternal time allocation in resource poor households may be quite challenging, and not allow the uptake of new and/or optimal behaviours

New Water-Soluble Copper(II) Complexes with Morpholine-Thiosemicarbazone Hybrids: Insights into the Anticancer and Antibacterial Mode of Action

Six morpholine-(iso)­thiosemicarbazone hybrids HL1–HL6 and their Cu­(II) complexes with good-to-moderate solubility and stability in water were synthesized and characterized. Cu­(II) complexes [Cu­(L1–6)­Cl] (1–6) formed weak dimeric associates in the solid state, which did not remain intact in solution as evidenced by ESI-MS. The lead proligands and Cu­(II) complexes displayed higher antiproliferative activity in cancer cells than triapine. In addition, complexes 2–5 were found to specifically inhibit the growth of Gram-positive bacteria Staphylococcus aureus with MIC50 values at 2–5 μg/mL. Insights into the processes controlling intracellular accumulation and mechanism of action were investigated for 2 and 5, including the role of ribonucleotide reductase (RNR) inhibition, endoplasmic reticulum stress induction, and regulation of other cancer signaling pathways. Their ability to moderately inhibit R2 RNR protein in the presence of dithiothreitol is likely related to Fe chelating properties of the proligands liberated upon reduction

New Water-Soluble Copper(II) Complexes with Morpholine-Thiosemicarbazone Hybrids: Insights into the Anticancer and Antibacterial Mode of Action

Six morpholine-(iso)thiosemicarbazone hybrids HL1-HL6 and their Cu(II) complexes with good-to-moderate solubility and stability in water were synthesized and characterized. Cu(II) complexes [Cu(L1-6)Cl] (1-6) formed weak dimeric associates in the solid state, which did not remain intact in solution as evidenced by ESI-MS. The lead proligands and Cu(II) complexes displayed higher antiproliferative activity in cancer cells than triapine. In addition, complexes 2-5 were found to specifically inhibit the growth of Gram-positive bacteria Staphylococcus aureus with MIC50 values at 2-5 μg/mL. Insights into the processes controlling intracellular accumulation and mechanism of action were investigated for 2 and 5, including the role of ribonucleotide reductase (RNR) inhibition, endoplasmic reticulum stress induction, and regulation of other cancer signaling pathways. Their ability to moderately inhibit R2 RNR protein in the presence of dithiothreitol is likely related to Fe chelating properties of the proligands liberated upon reduction

pH-Sensitive Peptide Hydrogels as a Combination Drug Delivery System for Cancer Treatment

Conventional antitumor chemotherapeutics generally have shortcomings in terms of dissolubility, selectivity and drug action time, and it has been difficult to achieve high antitumor efficacy with single-drug therapy. At present, combination therapy with two or more drugs is widely used in the treatment of cancer, but a shortcoming is that the drugs do not reach the target at the same time, resulting in a reduction in efficacy. Therefore, it is necessary to design a carrier that can release two drugs at the same site. We designed an injectable pH-responsive OE peptide hydrogel as a carrier material for the antitumor drugs gemcitabine (GEM) and paclitaxel (PTX) that can release drugs at the tumor site simultaneously to achieve the antitumor effect. After determining the optimal gelation concentration of the OE polypeptide, we conducted an in vitro release study to prove its pH sensitivity. The release of PTX from the OE hydrogel in the medium at pH 5.8 and pH 7.4 was 96.90% and 38.98% in 7 days. The release of GEM from the OE hydrogel in media with pH of 5.8 and 7.4 was 99.99% and 99.63% in 3 days. Transmission electron microscopy (TEM) and circular dichroism (CD) experiments were used to observe the microstructure of the peptides. The circular dichroism of OE showed a single negative peak shape when under neutral conditions, indicating a β-folded structure, while under acidic conditions, it presented characteristics of a random coil. Rheological experiments were used to investigate the mechanical strength of this peptide hydrogel. Furthermore, the treatment effect of the drug-loaded peptide hydrogel was demonstrated through in vitro and in vivo experiments. The results show that the peptide hydrogels have different structures at different pH values and are highly sensitive to pH. They can reach the tumor site by injection and are induced by the tumor microenvironment to release antitumor drugs slowly and continuously. This biologically functional material has a promising future in drug delivery for combination drugs