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Introduction: Chagas disease is an endemic parasitic infection in Latin America transmitted by triatomines. It is associated with risk factors such as poverty and rurality. After acute infection, a third of patients will present target organ involvement (heart, digestive tract, central nervous system). The remaining two thirds remain asymptomatic throughout their life. Pharmacological immunosuppression breaks the balance between the immune system and the parasite, favoring its reactivation. Clinical case: We present the case of a 58-year-old man from a Colombian rural area with a diagnosis of multiple myeloma refractory to the first line of treatment who required a new chemotherapy scheme and consolidation with autologous stem cell transplant. During the post-transplant period, he suffered from febrile neutropenia. Initial microbiological studies were negative but the peripheral blood smear evidenced trypomastigotes in blood. With a diagnosis of acute Chagas disease in a post-transplant patient, benznidazole was started. The evolution of the patient was satisfactory. Conclusions: Positive serology prior to transplantation makes it necessary to rule out reactivation of the pathology in the setting of febrile neutropenia. More studies are required to determine tools for estimating the probability of reactivation of the disease and defining the best cost-risk-benefit relation for the prophylactic therapy. [ABSTRACT FROM AUTHOR]

The objective of this project is to identify psychosocial variables that predict social responsibility among university students. A random selection was made of 500 students at a public university in southeastern Mexico, to complete questionnaires measuring social responsibility, self-concept, empathy, locus of control, coping with problems, and positive mental health. Correlations are reported between the variables and multiple regression analysis to predict social responsibility as well as each one of its dimensions (social participation, social management of knowledge, responsible management, and professional training). Self-satisfaction (a factor of positive mental health), personal discomfort (a factor of empathy), revaluing/direct confrontation, and self-concept (a constructive and affiliative social instrument) were found to predict social responsibility. The results generate alternatives for promoting social responsibility among students. [ABSTRACT FROM AUTHOR]

This paper proposes the theoretical bases for the elaboration of a new definition for Psychopathology, conceiving it as the study of the morbid impasses disturbing, or even preventing, the realization of a singular subject within the social bond. The notion of subject at issue is the one arising from the psychoanalytic thinking of Freud and Lacan. The (psycho)pathology of the subject relies on the ideas of Viktor von Waizsaecker, for whom "pathology", unlike the biological notion of "disease", is a phenomenon that presupposes a subject as such. It is also inspired by Pierre Fédida's work, which claims that psychopathology refers fundamentally to the subjective pathos, in its multiple semantic dimensions of passivity, suffering and passion. The consequences of the redefinition of the (psycho)pathology proposed here apply to the set of clinical practices, either medical-psychiatric or others, through the ethical and technical specification of the treatment, now guided by the care with the possible and responsible realization of the subject as a language being, inside the social bond. [ABSTRACT FROM AUTHOR]

Objective: This review integrates published scientific information about the fluorescence of natural teeth, dental resins and ceramics, and the main methods of analysis and quantification presented in the literature. Overview Fluorescence is an emission of light (photons) by a substance that has absorbed light of higher energy. In natural teeth, it is more intense in the dentin than in the enamel and presents a bluish‐white color. In dental resins and ceramics, fluorescence is obtained by the incorporation of materials that contain rare‐earth luminescence centers (more precisely lanthanide luminescence centers), which allows these artificial materials to simulate natural teeth in a more beautiful and vital‐looking way. However, the lack of knowledge about this optical phenomenon on the part of professionals indicates the need for more scientific studies and dissemination on this topic. Conclusions: Aesthetic materials have variable spectral compositions and fluorescence intensities, which are not always compatible with natural teeth. The fluorescence of teeth and restorative materials can be influenced by several factors, such as aging, temperature, and bleaching. Several devices for fluorescence evaluation and quantification are used in studies under different methodologies, but the small number of studies on the subject make it difficult to compare their results. Clinical Significance: Fluorescence is a fundamental optical property for aesthetic rehabilitations since its presence and intensity in the restorative materials allows achieving an aesthetic result much closer to reality. However, the fluorescent behavior of natural teeth and aesthetic restorative materials is not yet fully understood by researchers and clinicians. Greater understanding of this phenomenon will contribute to the selection, indication, and clinical use of these materials. [ABSTRACT FROM AUTHOR]

This work aims to relativize the psychoanalytic criticisms addressed to the psychiatric field based on the conception of the unitary, absolute and undivided existence of something that would function as "the Psychiatry". By showing the tensions existing within psychiatric psychopathology by the emergence of the subject and his/her singularity, we seek to indicate ways of constructing a Psychiatry based on an ethics of the subject and of his/her desire. [ABSTRACT FROM AUTHOR]

In this work, the influence of oxygen partial pressure on structural, morphological, and optical properties of TiO2 thin films grown on fused quartz substrate at different oxygen partial pressure by pulsed laser deposition were examined. X-Ray diffraction (XRD) patterns show the formation of TiO2 anatase phase deposited at high oxygen pressure. Atomic Force Microscopy (AFM) reveals that surface roughness of the films increases with oxygen pressure. Variation of surface morphology of films with increasing oxygen partial pressure was studied by AFM. It is observed that energy band gap of the films increases from 3.27 eV to 3.52 eV with the increase of oxygen pressure and is attributed to the decrease of oxygen defects. TiO2 thin films exhibited blue emission under the excitation of 320 nm wavelength. De-convoluted photoluminescence (PL) peaks showed that defect states are responsible for visible emission in TiO2 thin films. The intensity of PL emission associated with oxygen vacancies decreases with increasing oxygen pressure. Photometric characteristic analysis shows that the films deposited 1x10-4 mbar oxygen pressure exhibited intense blue emission with high luminescence efficacy of radiation. [ABSTRACT FROM AUTHOR]

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]

This paper presents the application of economic predictive control to minimize the cost of operating a nonisolated microgrid connected to an electric utility (EU) subject to a periodic internal demand. The microgrid considered is composed of a set of photovoltaic panels and two storage systems and it can buy and sell energy to an EU. The first storage system is composed of a cluster of batteries of lead acid, and the second storage system is based on hydrogen storage. A function that describes the economic cost of operating the plant taking into account aspects such as electric market costs, degradation of the microgrid, and amortization costs is proposed. Based on this cost and considering the periodic nature of the plant, an economic predictive controller capable of adapting to sudden changes on the cost function while guaranteeing stability and recursive feasibility has been successfully tested on a realistic nonlinear model of an experimental configurable testbed located in the laboratories of the University of Seville. [ABSTRACT FROM PUBLISHER]

The progress of modern psychiatry in the paths of biomedicine has led to the impression that psychopathology, as a science of human suffering in its various dimensions, would have become obsolete. A psychiatric nosology built exclusively on biological and experimental bases would take its place, definitely founding psychiatry as a medical specialty in its own right. This paper examines the dilemmas of that project to the reduction of the psychopathology into nosology and point some clues by which psychoanalytic theory of the subject and its pathos could provide the anthropological basis for the foundation of a psychopathology able to sustain psychiatric clinical practice. [ABSTRACT FROM AUTHOR]

Entropion is a common eyelid malposition in which the margin turns inward against the globe. If untreated, this condition can cause irritative symptoms like ocular discomfort, corneal abrasion, microbial keratitis, corneal vascularization, and visual loss. It may be classified as cicatricial, congenital, acute spastic and involutional. Involutional entropion is the most common type seen in general ophthalmic practice and its prevalence is increasing as the population ages. There are several treatment strategies including nonsurgical and surgical procedures. This paper describes the surgical techniques most commonly used to treat entropion: everting sutures (Quickert), transverse blepharotomy and marginal rotation (Weis procedure), orbicularis transfer technique, tarsal strip, and advancement of the lower lid retractors. [ABSTRACT FROM AUTHOR]

Through accurate photometry (resolution in hundredths of magnitude), it was obtained the luminous curve of the asteroid Toutatis, which wade its maximum approximation to the Earth (0.0104 A.U) at September 29th, 2004, and reached a magnitude of the order of 8.9 at September 28th of 2004. In some of the graphics we got it can be appreciated the variation of the brightness associated with this slow rotation movement of the asteroid which main period has been estimated at 7 days 48 minutes by other authors. This asteroid has a very complex rotation movement around two axes, which can be due to a collision with another body in the past. [ABSTRACT FROM AUTHOR]

This work presents a binary expansion (BE) solution approach to the problem of strategic bidding under uncertainty in short-term electricity markets. The BE scheme is used to transform the products of variables in the nonlinear bidding problem into a mixed integer linear programming formulation, which can be solved by commercially available computational systems. The BE scheme is applicable to pure price, pure quantity, or joint price/quantity bidding models. It is also possible to represents transmission networks, uncertainties (scenarios for price, quantity, plant availability, and load), financial instruments, capacity reinforcement decisions, and unit commitment. The application of the methodology is illustrated in case studies, with configurations derived from the 80-GW Brazilian system. [ABSTRACT FROM AUTHOR]

Presents information on a study regarding a Benders decomposition model to solve electric power transmission network expansion planning problems. Details on the mathematical model for the design problem; Application of Benders decomposition model; Information on Gomory cuts and Benders decomposition; Results and discussion.

This article aims to analyze agents' behavior in a competitive hydrothermal energy market. The idea is to investigate how much the day-to-day behavior of the market can be different from the predictions presented by cost-based models because of the risk perception of each agent (hydroelectric energy producer, in this case) as a participant of the market. The main contribution is in determining the impact on the agents' revenue in the short-term market due to the variation in the amount of energy generated and the market price, which other methodologies may not be able to capture. For this reason, a case study was made using daily simulations in a given month, observing the strategy and bids of eight hydroelectric agents for a central market operator emulated by an energy price offer simulator called SOPEE. The study reflected qualitative and quantitative examples of how the risk perception and the behavior of each agent can influence market behavior due to the variation in their perceptions of the parameters that form the energy price. [ABSTRACT FROM AUTHOR]

Aim: To compare eight large‐ and low‐tapered heat‐treated reciprocating instruments regarding their design, metallurgy, mechanical properties, and irrigation flow through an in silico model. Methodology: A total of 472 new 25‐mm E‐Flex Rex (25/.04 and 25/.06), Excalibur (25/.05), Procodile (25/.06), Reciproc Blue R25 (25/.08v), WaveOne Gold Primary (25/.07v), and Univy Sense (25/.04 and 25/.06) instruments were evaluated regarding their design (stereomicroscopy, scanning electron microscopy, and 3D surface scanning), metallurgy (energy‐dispersive X‐ray spectroscopy and differential scanning calorimetry), and mechanical performance (cyclic fatigue, torsional resistance, cutting ability, bending and buckling resistance). Computational fluid dynamics assessment was also conducted to determine the irrigation flow pattern, apical pressure, and wall shear stress in simulated canal preparations. Kruskal–Wallis and one‐way anova post hoc Tukey tests were used for statistical comparisons (α = 5%). Results: Instruments presented variations in blade numbers, helical angles, and tip designs, with all featuring non‐active tips, symmetrical blades, and equiatomic nickel‐titanium ratios. Cross‐sectional designs exhibited an S‐shaped geometry, except for WaveOne Gold. Univy 25/.04 and Reciproc Blue displayed the smallest and largest core diameters at D3. Univy 25/.04 and E‐Flex Rec 25/.04 demonstrated the longest time to fracture (p <.05). Reciproc Blue and Univy 25/.04 exhibited the highest and lowest torque to fracture, respectively (p <.05). Univy 25/.04 and Reciproc Blue had the highest rotation angles, whilst E‐Flex Rec 25/.06 showed the lowest angle (p <.05). The better cutting ability was observed with E‐Flex Rec 25/.06, Procodile, Excalibur, and Reciproc Blue (p >.05). Reciproc R25 and E‐Flex Rec showed the highest buckling resistance values (p <.05), with WaveOne Gold being the least flexible instrument. The impact of instruments' size and taper on wall shear stress and apical pressure did not follow a distinct pattern, although Univy 25/.04 and E‐Flex Rec 25/.06 yielded the highest and lowest values for both parameters, respectively. Conclusions: Low‐tapered reciprocating instruments exhibit increased flexibility, higher time to fracture, and greater angles of rotation, coupled with reduced maximum bending loads and buckling strength compared to large‐tapered instruments. Nevertheless, low‐tapered systems also exhibit lower maximum torque to fracture and inferior cutting ability, contributing to a narrower apical canal enlargement that may compromise the penetration of irrigants in that region. [ABSTRACT FROM AUTHOR]

Points out that asset reuse, cost-cutting, outsourcing to Asia and consolidation in the Electronics Manufacturing Service (EMS) business are expanding the list of challenges for Agilent Technologies. Challenge on how to continue to service customers, specially when EMS companies have consolidated their production lines, grown bigger and are more demanding in terms of service and advanced equipment. INSET: FINANCIAL WELLBEING.

A new approach for the stabilization of the ferroelectric orthorhombic ZrO2 films is demonstrated through nanosecond laser annealing (NLA) of as‐deposited Si/SiOx/W(14 nm)/ZrO2(8 nm)/W(22 nm), grown by ion beam sputtering at low temperatures. The NLA process optimization is guided by COMSOL multiphysics simulations. The films annealed under the optimized conditions reveal the presence of the orthorhombic phase, as confirmed by X‐ray diffraction, electron backscatter diffraction, and transmission electron microscopy. Macroscopic polarization‐electric field hysteresis loops show ferroelectric behavior, with saturation polarization of 12.8 µC cm−2, remnant polarization of 12.7 µC cm−2 and coercive field of 1.2 MV cm−1. The films exhibit a wake‐up effect that is attributed to the migration of point defects, such as oxygen vacancies, and/or a transition from nonferroelectric (monoclinic and tetragonal phase) to the ferroelectric orthorhombic phase. The capacitors demonstrate a stable polarization with an endurance of 6.0 × 105 cycles, demonstrating the potential of the NLA process for the fabrication of ferroelectric memory devices with high polarization, low coercive field, and high cycling stability. [ABSTRACT FROM AUTHOR]

Presents news related to software and semiconductor industries in Asia as of July 2004. Flextronics International's purchase of 55% share of Hughes Software Systems Ltd.; Hong Kong Science and Technology Parks Corp.'s partnership with Korean System Integration and Intellectual Property Authoring Center to create a semiconductor intellectual property exchange platform.

Points out that surging domestic and overseas demand for electronics equipment is expected to transform China's semiconductor industry into a $42 billion market by 2006. Combination of favorable government policies and tremendous surge in foreign investment; Plans to ramp up integrated circuit-making facilities; Initial public offerings to fuel the ramp up.

Reports on developments related to electrical engineering in Asia as of February 2004. Worldwide shortage of flat-screen monitors; Change in the focus of TCL International Holdings; Plan of Sharp to build successive large-LCD factories.

TiO2:Dy3+ powders without any secondary phases have been prepared by solid-state reaction through the optimization of synthesis conditions, doping amount and subsequently through a purification step. The maximum dysprosium solubility was found at 0.43 mol% in the range 800-900°C. The Rietveld refinement was performed to calculate the amount of phases and lattice constants. The effect of synthesis conditions and doping on strain and crystallite size is also discussed. Room temperature photoluminescence of TiO2:Dy3+ shows blue and yellow color emission. It is shown that yellow emission can be enhanced with the reduction of the pyrochlore phase Dy2Ti2O7. [ABSTRACT FROM AUTHOR]

Reports on the expected increase of text messages to be sent by mobile telephone users in China in 2004. Benefit of the increase for the operators; Number of short messages to be handled by the two mobile telecommunications operators; Implications of the growth for the customers.

Reports on Samsung Electronics Co. Ltd.'s decision to move its core liquid crystal display operations in South Korea. Construction of a seventh-generation fabrication plant; Reason for bypassing six-generation plant.

Reports on the growth of Internet-access revenues in China in 2003. Increase in broadband connections; Projected Internet and broadband access revenues in Asia by 2008.

Reports Advanced Micro Devices Inc.'s' announcement that China-based computer maker Lenovo Group Ltd. will use its chips for a line of desktop personal computers. Terms and conditions of the deal.

Reports on Japan-based Elpida Memory Inc.'s plan to build a large-scale advanced memory chip plant. Aim to catch up with industry leaders; Budget allocated for the project.

Reports on an investment to be made by Advanced Micro Devices (AMD) in an assembly and test facility for microprocessors in Suzhou, China. Company's other plant for packaging flash memory chips; Number of employees; Company's plan to open an engineering design center in Bangalore, India in July 2004; Indian plant's contribution to the design of AMD microprocessors.

Presents news briefs relating to telecommunication and electronics companies in the Asian region, compiled as of June 2004. Sony Corp.'s joint development with Toppan Printing Co. of a paper disc that holds more data than a digital videodisc (DVD); Chinese semiconductor company Green Mountain Integrated's plan to set up an eight-inch wafer facility in Nantong, Jiangsu Province in China; Toshiba Corp.'s budget for displays and semiconductor devices to help make up for its personal computer (PC) business.

Reports that Hewlett-Packard (HP) has beaten Asian market leader Lenovo in terms of total Asian personal computer (PC) sales in the first quarter of 2004. Number of computers shipped by the two companies; Market shares of other vendors such as IBM Corp., Dell and Samsung Electronics; Lenovo's market share in China; Increase in PC sales in the Asia-Pacific region, excluding Japan.

Reports on a handset joint venture formed by China-based TCL Corp. and France's Alcatel in April 2004. Alcatel's placement of its mobile phone production business with TCL; Alcatel's efforts to reduce its exposure to the mobile phone business, where it has been losing money and market share to Asian competitors; Right of TCL to buy Alcatel's stake; Deal's opening of the way for Alcatel's eventual withdrawal from the handset business; Alcatel's focus on building telecommunications equipment for carriers and commercial businesses.

Reports that German firm Siemens AG will partner with Chinese handset manufacturer Ningbo Bird to develop and market mobile handsets in China. Development of mobile phones to be sold under the Bird brand; Siemens' supply of the chipsets and platforms; Access to be gained by Siemens to Bird's outlets throughout China; Bird's use of Siemens' wireless modules for its phones; Entry into the major growth market of smaller cities and counties.

Presents news briefs relating to the Asian electronics industry, compiled as of June 2004. Samsung's goal of making a percentage of its output in China in 2004; Investment to be made by Canon to build a high-end copier plant in Japan; Joint venture called Eudyna Devices launched by Fujitsu and Sumitomo Electric Industries to make compound semiconductors used for home appliances.

Discusses the implications of China's adoption of its own third generation standardization, time division synchronous code division multiple access (TD-SCDMA). Aim of China to minimize foreign intellectual property rights owners; Ability of TD-SCDMA to encompass all radio deployment scenarios; Impact of China's TD-SCDMA on the wireless market.

Reports on the decision of Intel Corp. to stop selling its widely used Centrino Wifi chip package in China. Need for using a Chinese encryption software by overseas makers trying to sell wireless communication devices; Deadline for compliance in the use of Wapi; Factor affecting the delay of laptop computer purchases of consumers.

Reports on the plan of Matsushita Electric Industrial to shift production from Japan to China. Cuts in sales and production subsidiaries.

Reports that makers of handset components in Taiwan are struggling to supply big mobile phone companies with colour displays and camera lenses. Parts shortage problems of Motorola, Nokia and Siemens.

In this paper, we propose a flexible mixed-integer linear programming formulation of the AC OPF problem for distribution systems, using convexification and linearization techniques. The proposed formulation allows the representation of discrete decisions via integer decision variables, captures the nonlinear behavior of the electrical network via approximations of controllable accuracy, and can be solved to global optimality with commercial optimization solvers. The formulation is based on conventional variables that describe network behavior, which ensures its flexibility and the possibility of application to various distribution system problems, as we indicate with case studies. [ABSTRACT FROM PUBLISHER]

Climate change is the most serious environmental, social, and economic problem humanity is currently facing. Education is a fundamental pillar for societies in their efforts to address climate change, as stated in Article 12 of the Paris Agreement. In view of this imperative, the need to develop a Climate Change Education (CCE) plan that would be up to the challenge arose in the field of educational research. The guidelines for such a task are based on the study of four educational factors: the students, the teachers, the teaching and learning strategies and methods, and the goals of education. Research on these factors is abundant; nevertheless, there is a lack of these studies concerning Africa. Here, we present an exploratory study which focuses on students in Pemba (Mozambique) and aims to be the first step in the exploration and development of a basis for CCE in this country. We employed a questionnaire consisting of 38 closed-end items which was administered to 256 Mozambican students (aged 16–18). Findings suggest that students declared a limited knowledge about climate change, erroneous beliefs about the anthropogenic causes of climate change, and low levels of responsibility and risk perception. Further progress in the development of CCE in Mozambique would require future research to explore other educational factors with the aim of building a more accurate image of the educational reality of climate change in this country. [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]

Despite the uncertainty surrounding the design of a mechanism which is ultimately accepted by nations worldwide, the necessity to implement regulations to curb emissions of greenhouse gases on a global scale is consensual. The electricity sector plays a fundamental role in this puzzle and countries may soon have to revise their operating policy directives in order to make them compatible with additional constraints imposed by such regulations. We present a modeling approach for greenhouse gas emissions quotas which can be incorporated into a stochastic dual dynamic programming algorithm, commonly used to solve the hydro-thermal scheduling problem. Our approach is flexible and capable of accommodating a detailed representation of emissions and related constraints. A case study based on the Guatemalan power system exemplifies the potential effects of considering these restrictions. [ABSTRACT FROM PUBLISHER]

This work develops a stochastic optimization model for the creation of a bidding strategy for a generator in an energy call option auction similar to Brazil's, i.e., where the bidder can offer both the premium and the strike price. The objective of the model is to maximize the bidder's competitiveness while ensuring that the project's target rate of return is achieved with a given probability, for example 95%. The problem's complexity is compounded by uncertainties in fuel supply and the need to switch between fuels. The generators face the conundrum of bidding a single strike price to cover the expenses generated by using multiple types of fuels. We address the problem of finding bidding strategies which, taking into account uncertainty in fuel supply and risk constraints, set the combination of strike price and option premium that ensure a desired risk-adjusted return for greenfield dual-fuel thermal plants. [ABSTRACT FROM PUBLISHER]

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]

The growth of the global population, together with climate change and water scarcity, has made the shift towards efficient and sustainable agriculture increasingly important. Undoubtedly, the recent development of low-cost IoT-based sensors and actuators offers great opportunities in this direction since these devices can be easily deployed to implement advanced monitoring and irrigation control techniques at a farm scale, saving energy and water and decreasing costs. This paper proposes an economic and periodic predictive controller taking advantage of the irrigation periodicity. The goal of the controller is to find an irrigation technique that optimizes water and energy consumption while ensuring adequate levels of soil moisture for crops, achieving the maximum crop yield. For this purpose, the developed predictive controller makes use of soil moisture data at different depths, and it formulates a constrained optimization problem that considers energy and water costs, crop transpiration, and an accurate dynamical nonlinear model of the water dynamics in the soil, reflecting the reality. This controller strategy is compared with a classical irrigation strategy adopted by a human expert in a specific case study, demonstrating that it is possible to obtain significant reductions in water and energy consumption without compromising crop yields. [ABSTRACT FROM AUTHOR]

Transmission planning studies in hydrothermal systems deal with complex issues. Two include 1) the need for a robust grid that can accommodate a large number of economic dispatch patterns caused by differing hydrological conditions in the river basins and 2) the high cost of grid reinforcements due to the large distance from hydro plants to load centers and the required N-1 security criterion. It is thus necessary to consider the tradeoff between supply reliability and reinforcement cost. The resulting planning problem is formulated as a large-scale mixed integer nonlinear optimization model. The objective function is to minimize the sum of investment costs and expected load-shedding costs. The constraints include linearized power flow equations, limits on circuit flows for all combinations of economic dispatch points (which capture hydrological variation), and circuit contingencies (which capture supply reliability). This paper describes a new solution scheme for this problem that is based on two techniques: 1) the extension of a binary disjunctive technique, which transforms the integer nonlinear problem into a linear one and 2) screening strategies, which allow a judicious choice of contingencies and candidate circuits. Planning studies for Brazil and Bolivia are presented and discussed. [ABSTRACT FROM AUTHOR]