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In this paper the application of a novel robust predictive controller for tracking periodic references to a section of Barcelona's drinking water network is presented. The system is modeled using a large scale uncertain differential-algebraic discrete time linear model in which it is assumed that a prediction of the water demand is available and that it is affected by unknown and bounded uncertainties. The control objective is to satisfy the water demand while trying to follow a given reference of the level of the tanks of the network. The controller considered has been modified to account for algebraic equations and large scale models and it joins a dynamic trajectory planner and a robust predictive controller in a single layer to guarantee that the closed-loop system converges asymptotically to a neighborhood of optimal reachable periodic trajectory satisfying the constraints for all possible uncertainties even in the presence of sudden changes in the reference. To demonstrate these properties three different simulation scenarios have been considered. [ABSTRACT FROM AUTHOR]

There is a growing appreciation of the role of aquaculture in improving food and nutrition security in Timor-Leste. The Timor-Leste government's National Aquaculture Development Strategy (NADS; 2012–30) envisions to increase domestic aquaculture production to 12,000 tons to achieve per capita fish consumption of 15 kg annually by 2030. However, aquaculture development is constrained by limited access to quality seed, feed, and improved technologies. WorldFish has been collaborating with the Ministry of Agriculture and Fisheries since 2015 to help realise the target. The objective was to present step-wise interventions – Genetically Improved Farmed Tilapia (GIFT) hatcheries establishment and monosex seed production and distribution; conduct of on-farm grow-out trials; training and capacity building; and extension, communication and marketing services - carried out, and demonstrate how availability, accessibility and consumption of fish could be increased sustainably in the subsistence farming systems of Timor-Leste. Farmers' participatory grow-out trials following better management practices (BMPs) were conducted in two phases from 2015 to 2023 across ten farmers clusters in four municipalities in inlands. The trials in Phase 1 tested GIFT stocked at 3 fingerlings/m2 using green water in ponds and fed with locally made plant-based feed. In Phase 2, trials tested GIFT stocked at 5 fingerings/m2 with high quality imported pelleted feed supplemented with local feed and green water. To facilitate scaling, local service providers, feed importers and fish market operators were trained to facilitate input supply and output marketing. In Phase-1, one existing public hatchery was upgraded for producing and supplying quality GIFT broodstock to private hatcheries and one private hatchery was established with public-private partnership (PPP) model. On-farm trials showed that farmers following BMPs and feeding with farm made feed achieved fish yield averaging 4.3 ± 1.5 t/ha/11 months production cycle. In Phase-2, PPP model hatcheries were established; nursery operators connected to each hatchery started nursing fry to fingerlings to local farmers. On-farm trials results managed by 169 farmers in 417 ponds during 2020–2022 showed fish yield of 12.4 ± 0.1 t/ha/ 6 month cycle with full BMPs , suggesting the viability of GIFT intensification across Timor-Leste. Continuous technical backstopping of public and private sectors, however, is crucial for scaling and sustainable intensification of aquaculture. GIFT aquaculture development model of Timor-Leste has potential for scaling across the country for reducing peoples' malnutrition and poverty. The model can also potentially be replicated to other small island nations of the Asia-Pacific region and beyond. [Display omitted] • Sustainable intensification of genetically improved farmed tilapia (GIFT) in the subsistence farming systems • On-farm trialsfollowed unique methods, fostering linkages across value chain for provisioning of input and services • Fish yield increased to 12.4 t/ha/cycle from 4.3 t/ha/cycle(∼300% increment) as a result of sustainable intensification • One-third (33%) of the tilapia produced by farmers contributed to the food and nutrition security of the rural communities • Economically, small-scale aquaculture has proven to be highly attractive, with a gross profit of 136% • The proven aquaculture development model has potential for scaling in Timor-Leste and the pacific island nations [ABSTRACT FROM AUTHOR]

In this work, the formation of the orthorhombic phase of ZrO 2 together with the minor monoclinic phase were elucidated by X-ray diffraction and transmission electron microscopy. Moreover, oxidized W can be responsible for the formation of oxygen vacancies in the ZrO 2 through oxygen scavenging. The ferroelectric properties of the W/ZrO 2 /W film capacitors were investigated through piezoresponse force microscopy (PFM) and polarization-voltage measurements. A second-order phase transition from the polar orthorhombic phase to the non-polar tetragonal phase was observed. Density functional theory calculations confirm our experimental results and propose that oxygen vacancies are responsible for the Curie–Weiss temperature of 130 °C, significantly lower than the theoretical value for the bulk. • Dielectric properties of ferroelectric orthorhombic ZrO 2 films were investigated. • An activation energy of 0.48 eV was estimated which can be associated to oxygen vacancies. • DFT calculations suggest that oxygen vacancies are responsible for lowering the Curie–Weiss temperature. [ABSTRACT FROM AUTHOR]

Abstract: Overnutrition during critical developmental periods is believed to be a risk factor for the emergence of metabolic disorders in adulthood. The present study investigated the effects of pups overfeeding during lactation on offspring''s insulin secretion. To study the consequences of overnutrition early in life in rats, litter size reduction has been shown to be an appropriate experimental model. To induce early postnatal overnutrition, litter size was reduced to three pups per litter at the third day following birth [overfed group (OG)]. In the control group (CG), the litter size was adjusted to 10 pups per litter. Metabolic parameters and glucose-stimulated insulin secretion were assessed. OG pups ingested more milk at 10 and 21 days and had an augmented food intake at 1 year compared to the CG. Consistently, body weight, body fat, and fasting plasma levels of insulin were higher in 1-year-old OG rats. In addition, OG rats exhibited enhanced insulin secretion, accompanied by elevated content of GLUT-2 in pancreatic islets compared to CG. These findings indicate that early postnatal overnutrition during a critical developmental period in life may program permanent alterations in glucose-stimulated insulin secretion. [Copyright &y& Elsevier]

CdS nanoparticles (NPs) were synthesized using colloidal methods and incorporated within a diureasil hybrid matrix. The surface capping of the CdS NPs by 3-mercaptopropyltrimethoxysilane (MPTMS) and 3-aminopropyltrimethoxysilane (APTMS) organic ligands during the incorporation of the NPs within the hybrid matrix has been investigated. The matrix is based on poly(ethylene oxide)/poly(propylene oxide) chains grafted to a siliceous skeleton through urea bonds and was produced by sol–gel process. Both alkaline and acidic catalysis of the sol–gel reaction were used to evaluate the effect of each organic ligand on the optical properties of the CdS NPs. The hybrid materials were characterized by absorption, steady-state and time-resolved photoluminescence spectroscopy and High Resolution Transmission Electron Microscopy (HR-TEM). The preservation of the optical properties of the CdS NPs within the diureasil hybrids was dependent on the experimental conditions used. Both organic ligands (APTMS and MPTMS) demonstrated to be crucial in avoiding the increase of size distribution and clustering of the NPs within the hybrid matrix. The use of organic ligands was also shown to influence the level of interaction between the hybrid host and the CdS NPs. The CdS NPs showed large Stokes shifts and long average lifetimes, both in colloidal solution and in the xerogels, due to the origin of the PL emission in surface states. The CdS NPs capped with MPTMS have lower PL lifetimes compared to the other xerogel samples but still larger than the CdS NPs in the original colloidal solution. An increase in PL lifetimes of the NPs after their incorporation within the hybrid matrix is related to interaction between the NPs and the hybrid host matrix. [ABSTRACT FROM AUTHOR]

The incorporation of CdS nanoparticles (NPs), as prepared through colloidal methods using reverse micelles, within diureasil hybrid organic–inorganic sol–gel matrices was investigated. Several experimental conditions, namely the influence of capping agent 3-mercaptopropyltrimethoxysilane (MPTMS) or the use of tetraethoxysilane (TEOS), were studied in order to assure the preservation of the original optical properties of colloidal CdS NPs after the incorporation of the NPs within the solid diureasil hybrid matrix. The diureasil matrix is based on a siliceous network cross linked through urea bonds to poly(oxyethylene)/poly(oxypropylene) (PEO/PPO) chains. The influence of the Cd 2+ /S 2− molar ratio of the NPs in the stability and dispersion of the NPs within the diureasil matrix was also investigated. The obtained CdS doped hybrid matrix was characterized by absorption, steady-state and time-resolved photoluminescence (PL) spectroscopy and by transmission electron microscopy (TEM). The stability of the CdS NPs within the hybrid matrix showed to be dependent on the Cd 2+ /S 2− molar ratio used in the synthesis of the NPs. The use of MPTMS proved to be crucial in the preservation of the original optical properties of the colloidal CdS NPs after the incorporation of the NPs within the hybrid matrix. The effect of MPTMS was in turn influenced by the Cd 2+ /S 2− molar ratio employed in the synthesis of the CdS NPs. The use of MPTMS was less effective when Cd 2+ /S 2− molar ratio equal to 0.5 was used. In the absence of MPTMS or TEOS larger NPs size distribution and clustering of the CdS NPs were obtained after the transfer of the NPs into the hybrid matrix. [ABSTRACT FROM AUTHOR]

Abstract: Optically clear and flexible organic–inorganic hybrid materials doped with CdSe nanoparticles (NPs) were synthesized by a sol–gel method based on the hydrolysis and condensation reactions of ureasilicate precursors. The CdSe NPs were produced by a colloidal method using reverse micelles and were then transferred to the ureasilicate precursor solution followed by gelation of the mixture using ammonia/water vapours as catalyst for the sol–gel process. The influence of the NPs surface in the dispersion of the NPs within the matrix was investigated by the addition of a capping agent with both thiol and siloxane groups (3-mercaptopropyltrimethoxysilane, MPTMS). This capping agent was used in order to improve compatibility and avoid aggregation of the NPs within the matrix and to increase the preservation of the original optical properties of the NPs. The nanocomposites obtained were characterized by absorption spectroscopy, steady-state photoluminescence, time resolved photoluminescence, HRTEM and FTIR spectroscopy. The results obtained showed the influence of the use of MPTMS in the preservation of the original optical properties of the CdSe NPs after their transfer into the ureasilicate matrix. The HRTEM analysis showed the presence of well-dispersed spherical NPs with well-defined lattice fringes. The obtained nanocomposites exhibit high transparency in the visible range as a result of the good dispersion of the NPs within the matrix, showing the potentials of the developed method in the production of composite materials in which the optical properties of the NPs incorporated are crucial to the desired application. [Copyright &y& Elsevier]

Highlights: [•] In situ synthesis of CdSe nanoparticles within a hybrid ureasilicate matrix. [•] Influence of Cd/MPTMS and Cd/Se molar ratios in optical properties of nanocomposites. [•] Absorption and PL spectra of doped xerogels show features of quantum size effect. [•] PL decay profiles of doped xerogels showed to be dependent on the Cd/Se molar ratio. [ABSTRACT FROM AUTHOR]

We present preclinical studies that demonstrate in vitro the feasibility and efficacy of lentivirus-based vector antisense gene therapy for control of HIV replication in primary T lymphocytes isolated from HIV-infected patients discordant for clinical status. VRX496 is a VSV-G-pseudotyped HIV-based vector that encodes an antisense payload against the HIV envelope gene. The antisense payload is under the control of the native LTR promoter, which is highly transactivated by tat upon HIV infection in the cell. Transfer of autologous CD4+ T lymphocytes genetically modified with VRX496 (VRX496T) into HIV-infected patients is intended to provide a reservoir of cells capable of controlling HIV, potentially delaying AIDS onset. To determine the patient population likely to respond to VRX496 for optimal efficacy, we examined the ability of our research vector, VRX494, to modify and suppress HIV in vitro in lymphocytes isolated from 20 study subjects discordant for CD4 count and viral load. VRX494 is analogous to the clinical vector VRX496, except that it contains GFP as a marker gene instead of the 186-tag marker in the clinical vector. To transfer VRX494 to target cells we developed a novel scalable two-step transduction procedure that has been translated to the clinic in an ongoing clinical trial. This procedure achieved unprecedented transduction efficiencies of 94 ± 5% in HIV+ study subject cells. In addition the vector inhibited HIV replication ≥93% in culture regardless of the viral load or CD4 count of the subject or tropism of the virus strain with which they were infected. These findings demonstrate that VRX496T therapy is expected to be beneficial to patients that differ in their status in term of CD4 count and viral load. The methods described represent significant technical advances facilitating execution of lentivirus vector-mediated gene therapy for treatment of HIV and are currently being employed in the first trial evaluating lentivirus vector safety in humans. [Copyright &y& Elsevier]

• MCMC used to obtain samples of supply failure states used in IS optimization. • Stratification used to represent VRE and load variation. • Preserves daily and seasonal variation, temporal and spatial correlation. • Reliability indices estimated using VRT-based Monte Carlo Simulation. • Speedups of 300 to 800 times compared with the standard MCS. This paper presents a new methodology for Monte Carlo-based multi-area reliability assessment based on optimal Importance Sampling (IS), Markov Chain Monte Carlo (MCMC) and optimal stratification. The proposed methodology allows the representation of relevant features of variable renewable energy (VRE) resources such as intermittency, daily and seasonal variation and spatial correlation with other sources (e.g. correlation between wind and hydro). The effectiveness of the proposed methodology is illustrated with case studies based on the Saudi Arabia and Chilean systems, with speedups of 300 and 800 times compared with the standard Monte-Carlo simulation. [ABSTRACT FROM AUTHOR]