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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]

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]

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]

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]

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]

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]

Bone defects are a challenging clinical situation, and the development of hydroxyapatite-based biomaterials is a prolific research field that, in addition, can be joined by stem cells and growth factors in order to deal with the problem. This study compares the use of synthetic hydroxyapatite and xenograft, used pure or enriched with bone marrow mononuclear fraction for the regeneration of critical size bone defects in rat calvaria through histomorphometric (Masson's staining) and immunohistochemical (anti-VEGF, anti-osteopontin) analysis. Forty young adult male rats were divided into five groups (n = 8). Animals were submitted to critical size bone defects (Ø = 8 mm) in the temporoparietal region. In the control group, there was no biomaterial placement in the critical bone defects; in group 1, it was filled with synthetic hydroxyapatite; in group 2, it was filled with xenograft; in group 3, it was filled with synthetic hydroxyapatite, enriched with bone marrow mononuclear fraction (BMMF), and in group 4 it was filled with xenograft, enriched with BMMF. After eight weeks, all groups were euthanized, and histological section images were captured and analyzed. Data analysis showed that in groups 1, 2, 3 and 4 (received biomaterials and biomaterials plus BMMF), a significant enhancement in new bone matrix formation was observed in relation to the control group. However, BMMF-enriched groups did not differ from hydroxyapatite-based biomaterials-only groups. Therefore, in this experimental model, BMMF did not enhance hydroxyapatite-based biomaterials' potential to induce bone matrix and related mediators. [ABSTRACT FROM AUTHOR]

Background Whole body vibration exercise (WBVE) has been shown to improve muscular strength and power, and increase peripheral blood flow. The aim of this study was to evaluate the behavior of the skin temperature (Tsk) on regions of the lower limbs from an acute bout of WBVE. Methods and findings Cross-sectional study approved by local ethics committee (Certificado de Apresentação para Apreciação Ética—CAAE—19826413.8.0000.5259) and Trial registration (Registro Brasileiro de Ensaios Clı´nicos—REBEC—RBR-738wng). Using Infrared thermography (IRT), Tsk and thermal symmetry of the posterior lower extremities (thigh, knee, calf and heel) were examined in 19 healthy participants. IRT was assessed during 60-second WBVE exposures of 0, 30 and 50 Hz. From the adjusted linear mixed effects model, vibration frequency, time and regions of the lower extremity were significant (p<0.001). However, the variable laterality was not significant (p = 0.067) and was excluded from the adjusted statistical model. The adjusted model was significant (p<0.00001) and all variables in the model were significant (p<0.01) indicating that Tsk decreases with time, independently of the vibration frequency. The value of the Pseudo-R-Squared for the model was 0.8376. The presented mathematical model of the current study may be useful to justify the patterns observed for all vibration frequencies between and 0 and 50 Hz. The main limitations of the study were the reduced time of the intervention and not having evaluated other regions of the body. Conclusions The acute exposure of 60-second mechanical vibration has effect on the behavior of Tsk of the posterior region of the lower limbs, which is likely to be associated with a decrease on the blood flow due to WBVE. It is speculated that during WBVE a greater supply of blood is required where the body responds by shunting blood flow from the skin to working muscle in the first seconds of exercise. Further investigative work is required to verify this hypothesis. [ABSTRACT FROM AUTHOR]

Physical activity is recommended in the management of individuals with metabolic syndrome (MetS), and recent studies have suggested whole-body vibration exercise (WBVe) for this population. The aim of this study was to evaluate the functionality through the Short Physical Performance Battery (SPPB) in individuals with MetS after WBVe. The SPPB evaluates the balance, the gait speed, and the lower limb strength (five-chair stand [5CS] test). Forty-four individuals with MetS were divided into WBVe (WBVeG) and control (CG) groups. The individuals of the WBVeG performed 10 sessions of WBVe in an oscillating/vibratory platform (OVP), barefoot, for 3 minutes at the peak-to-peak displacements of 2.5, 5.0, and 7.5 mm, with a resting period of 1 minute (total time: 18 minutes/session). The frequencies ranged from 5 up to 14 Hz. The individuals of the CG performed all the steps of the study, but the OVP was turned off. Before the first and after the tenth session, the individuals performed the SPPB. Significant responses were found in the WBVeG, analyzing the total score of the SPPB (P ¼ .005), the balance test (P ¼ .01), the gait speed (P ¼ .006), and the 5CS test (P ¼ .03), resulting in the improvement of the functionality of individuals with MetS. [ABSTRACT FROM AUTHOR]

The optimal scheduling of hydrothermal systems requires the representation of uncertainties in future streamflows to devise a cost-effective operations policy. Stochastic optimization has been widely used as a powerful tool to solve this problem but results will necessarily depend on the stochastic model used to generate future scenarios for streamflows. Periodic autoregressive (PAR) models have been widely used in this task. However, its parameters are typically unknown and must be estimated from historical data, incorporating a natural estimation error. Furthermore, the model is just a linear approximation of the real stochastic process. The consequence is that the operator will be uncertain about the correct linear model that should be used at each period. The objective of this work is to assess the impacts of incorporating the uncertainty of the parameters of the PAR models into a stochastic hydrothermal scheduling model. The proposed methodology is tested with case studies based on data from the Brazilian hydroelectric system. It is shown that when the uncertainty of the parameters is ignored, the policies given by the stochastic optimization tend to be too optimistic. [ABSTRACT FROM AUTHOR]

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]

The development of new bone substitutes has become an area of great interest in materials science. In fact, hydroxyapatite is the most commonly used biomaterial in defects that require bone reconstruction, and that is certainly why the discovery of new products with its formulation has been increasing continuously. The aim of this study was to analyze the biological behavior of a xenogeneic hydroxyapatite widely disclosed in the literature and a synthetic nano-hydroxyapatite/Beta tricalcium phosphate in critical defects in the calvaria of Wistar rats. For this, the groups were divided as follows: 24 adult male Wistar rats were used, weighing between 300 and 350 g, in three groups with eight animals each. In the CTRL group (control), only the clot was kept, without material insertion; in the Bioss group (bovine hydroxyapatite), Bio Oss®—Gleistlich® was introduced; and in the Blue Bone group (REG), the defect was filled in with synthetic nano-hydroxyapatite associated with betatriphosphate of calcium, Blue Bone®—Regener®. According to the results in Goldner's Trichromics, we can observe a higher percentage of newly formed bone matrix in the REG group than in the CTRL and Bioss groups; in the VEGF, we had a more adequate cell modulation for blood vessel formation in the Blue Bone group (REG) compared to the Bioss and CTRL groups, while in osteopontin, a higher percentage of bone formation was observed in the Blue Bone group (REG) and Bioss group when compared to the CTRL group. We conclude that bone formation, mitosis-inducing cell modulation and main osteoblast activity were higher in the Blue Bone group (REG) than in the CTRL and Bioss groups. [ABSTRACT FROM AUTHOR]

• 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]