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In this study, the combination of Inconel 718 (IN718) alloy, widely used in aerospace applications, and a highly conductive low-density Aluminium (Al) was hypothesized to achieve a disruptive solution with improved thermal conductivity and significantly lower weight, key aspects of aerospace industry. A multi-material IN718 – Al solution was designed and later fabricated by combining laser surface texturing and hot-pressing techniques. The multi-material IN718 – Al specimens were produced without significant defects and exhibited a significantly lower density than the IN718 bulk (

A home-made 3D Multi-Material Laser Powder Bed Fusion (3DMMLPBF) technology was exploited to manufacture novel multi-material Ti6Al4V-CoCrMo parts. This multi-material concept aims to bring to life a new and disruptive material's design concept for the acetabular cup. Only using a layer-by-layer approach it is possible to manufacture an acetabular cup capable to combine CoCrMo alloy wear resistance and Ti6Al4V alloy bone-friendly nature, in a single component, fabricated at once. This system works with multiple powder deposition functions and vacuum cleaning procedures allowing to use two different powders (Ti6Al4V and CoCrMo) in each layer and thus, allowing to construct 3D Multi-Material transition between distinct materials, point-by-point and layer-by-layer. In this sense, the manufacturing strategies and the functional transition between Ti6Al4V and CoCrMo with a mechanical interlocking were analyzed and discussed both from mechanical and metallurgical point of view. A small diffusion area and no evidence of defects or cracks can be found in the transition's regions between the distinct materials which are strong evidences of a solid metallurgical bonding at the interfacial regions of Ti6Al4V and CoCrMo materials. A functional transition is also obtained through a design capable to provide a 3D mechanical interlocking with potential of assuring, simultaneously, tensile and compressive strength. This proof of concept might be a step-ahead in Laser Powder Bed Fusion in which the most desired intrinsic of individual materials can be combined in a single component targeting biomedical disruptive solutions.

Classic galactosemia is an inborn error of metabolism caused by deleterious mutations on the GALT gene, which encodes the Leloir pathway enzyme galactose-1-phosphate uridyltransferase. Previous studies have shown that the endoplasmic reticulum unfolded protein response (UPR) is relevant to galactosemia, but the molecular mechanism behind the endoplasmic reticulum stress that triggers this response remains elusive. In the present work, we show that the activation of the UPR in yeast models of galactosemia does not depend on the binding of unfolded proteins to the ER stress sensor protein Ire1p since the protein domain responsible for unfolded protein binding to Ire1p is not necessary for UPR activation. Interestingly, myriocin - an inhibitor of the de novo sphingolipid synthesis pathway - inhibits UPR activation and causes galactose hypersensitivity in these models, indicating that myriocin-mediated sphingolipid depletion impairs yeast adaptation to galactose toxicity. Supporting the interpretation that the effects observed after myriocin treatment were due to a reduction in sphingolipid levels, the addition of phytosphingosine to the culture medium reverses all myriocin effects tested. Surprisingly, constitutively active UPR signaling did not prevent myriocin-induced galactose hypersensitivity suggesting multiple roles for sphingolipids in the adaptation of yeast cells to galactose toxicity. Therefore, we conclude that sphingolipid homeostasis has an important role in UPR activation and cellular adaptation in yeast models of galactosemia, highlighting the possible role of lipid metabolism in the pathophysiology of this disease.

WC-Co cutting tools performance under demanding cutting conditions largely depend on the efficiency of the cutting fluid, mainly its ability to remove heat and reduce friction, both highly dependent on the wettability and drop spreading behaviour of the fluid. In this context, this study focuses on the spreading behaviour of machining cutting fluid and water in WC-10 wt%Co cutting tools surface. Contact angles were experimentally measured and then used for performing numerical simulations by the level set method. A contact angle of 75.3˚ and 92.8˚ were measured for the machining cutting fluid and distilled water, respectively, and coincident values were found by numerical simulation, as well as a strong agreement in the drop shape. It was also possible to observe that machining cutting fluid has a lower spreading time than water, due to a lower contact angle and higher viscous dissipation, allowing to reach equilibrium phase sooner. Also, the machining cutting fluid presents a higher drop radius than water, meaning a 24.2% contact area increase over 50 ms of spreading time. Furthermore, numerical simulation showed that the drops spreading over the capillary-inertial time, at the early stage of spreading, follow an exponential dependency with a spreading factor of approximately t1/2, which indicates that the initial spreading of both drops is driven and controlled by the balance between inertial and capillary forces. This work intends to contribute to the knowledge on the phenomena that drive the drop spreading behaviour on WC-10 wt%Co cutting tools, being the development of numerical models to predict this behaviour of utmost importance, since it can lead to the development of novel surface improved tools, with an enhanced lubrification effect and heat removal capacity closer to the cutting zone during machining processes, and consequently allowing an improvement in the tribological and cutting performance of these tools published

Funding Information: This work was supported by FCT (Fundação para a Ciência e a Tecnologia) through the grant SFRH/BD/140191/2018 , the work contract CEECIND/04794/2007 , the project PTDC/EME-EME/1442/2020 (Add2MechBio) and the project NORTE-01-0145-FEDER-029968 . This work has been also funded by ICVS Scientific Microscopy Platform, member of the national infrastructure PPBI - Portuguese Platform of Bioimaging ( PPBI–POCI-01-0145-FEDER-022122 ). Additionally, it was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 , UIDP/50011/2020 & LA/P/0006/2020 , financed by national funds through the FCT/MEC (PIDDAC). Finally, this work was supported by FCT national funds, under the national support to R&D units grant, through the reference projects UIDB/04436/2020 , UIDP/04436/2020 , UIDB/50026/2020 and UIDP/50026/2020 . Publisher Copyright: © 2022 Elsevier Ltd In this study, Selective Laser Melting (SLM) was used to produce mono-material Ti64Al4V- and NiTi-cubic cellular structures with an open-cell size and wall thickness of 500 μm and 100 μm, respectively. Bioactive beta-tricalcium phosphate (βTCP) and polymer poly-ether-ether ketone (PEEK) were used to fill the produced structures open-cells, thus creating multi-material components. These structures were characterized in vitro in terms of cell viability, adhesion, differentiation and mineralization. Also, bio-tribological experiments were performed against bovine plate to mimic the moment of implant insertion. Results revealed that metabolic activity and mineralization were improved on SLM mono-material groups, when compared to the control group. All cell metrics were improved with the addition of PEEK, conversely to βTCP where no significant differences were found. These results suggest that the proposed solutions can be used to improve implants performance.

Environmental enrichment (EE) is an animal management technique, which seems to improve adaptation to the experimental conditions of housing in laboratory animals. Previous studies have pointed to different beneficial effects of the procedure in the treatment of several disorders, including psychiatric conditions such as depression. The anxiolytic effects induced by EE, on the other hand, are not as clear. In fact, it has been proposed that EE acts as a mild stressor agent. To better understand the relationship of EE with anxiety-related responses, the present study exposed rats to one week of EE and subsequently tested these animals in the inhibitory avoidance and escape tasks of the elevated T-maze (ETM). In clinical terms, these responses have been respectively related to generalized anxiety and panic disorder. All animals were tested in an open field, immediately after the ETM, for locomotor activity assessment. Additionally, analysis of delta FosB protein immunoreactivity (FosB-ir) was used to map areas activated by EE exposure and plasma corticosterone measurements were performed. The results obtained demonstrate that exposure to EE for one week impaired avoidance responses, an anxiolytic-like effect, without altering escape reactions. Also, in animals submitted to the avoidance task EE exposure decreased FosB-ir in the cingulate cortex, dorsolateral and intermediate lateral septum, hippocampus (cornus of Ammon), anterior and dorsomedial hypothalamus, medial and basolateral amygdala and ventral region of the dorsal raphe nucleus. Although no behavioral differences were observed in animals submitted to the escape task, EE exposure also decreased FosB-ir in the cingulate cortex, hippocampus (dentate gyrus), lateral amygdala, paraventricular, anterior and ventromedial hypothalamus, dorsomedial periaqueductal gray and ventral and dorsal region of the dorsal raphe. No changes in corticosterone levels, however, were observed. These results contribute to a better understanding of the effects of EE on anxiety.

In a previous study, we showed that exposure of rats to a one-week environmental enrichment (EE) protocol decreases elevated T-maze (ETM) avoidance responses, an anxiolytic-like effect, without altering escape reactions, in clinical terms related to panic disorder. These anxiolytic-like effects were followed by decreased delta FosB-immunoreactivity (delta FosB-ir) in the cingulate cortex, dorsolateral and intermediate lateral septum, hippocampus (cornus of Ammon), anterior and dorsomedial hypothalamus, medial and basolateral amygdala and ventral region of the dorsal raphe nucleus. The purpose of the present study was to further investigate behavioral and neurophysiological alterations induced by EE exposure. For that, in a first experiment we verified if increasing the time of exposure to the same EE protocol used in our previous study (from one to two weeks) altered male Wistar rats’ ETM escape responses. All animals were tested in an open field, immediately after the ETM, for locomotor activity assessment. Since anxiety and panic-related reactions have been associated to the functioning of specific subnuclei of the dorsal raphe nucleus (DR), we also evaluated delta FosB-ir in serotonergic cells of DR regions. At last, we analyzed plasma corticosterone levels in animals submitted to EE and to standard housing. Results showed that a two-week exposure to EE decreases both ETM avoidance and escape reactions, inducing anxiolytic and panicolytic-like effects, respectively. There was also a significant decrease in the number of double staining neurons in the midrostral region of the dorsal subnucleus of the dorsal raphe. No changes in corticosterone levels, however, were observed. These results contribute to a better understanding of the effects of EE on anxiety and panic-related responses.

The polydimethylsiloxane (PDMS)/ZnO nanocomposite coatings were deposited on the borosilicate substrate by spray method. ZnO nanoparticles were synthesized by polyol method and further surface modification by functionalization with [(3-Aminopropyl)triethoxysilane] (APTS) in different concentrations (0.5, 1.0, and 1.5 ml). The results showed that there is an influence in the exposure to UV radiation and a decrease in the temperature, consequently presenting decreases in the contact angle of ZnO/PDMS nanocomposites. The 0.5 ml of APTS was the best design for ZnO/PDMS nanocomposite with photocatalytic and hydrophobic characteristics, showing a contact angle of 117° and 25% of MB discoloration in 90 min

The high moisture content of pepper makes it a highly perishable product, being necery studies to inform better conditions of processing, storage and packaging for this product. For drying and storage, knowledge of the relationship between the moisture of the material and the relative humidity is essential since the sorption isotherms (adsorption and desorption) help to establish the final water content in the product. The objective of this study was to determine and analyze the curves of sorption of pepper whole and in paste, at temperatures of 20, 30, 40 and 50oC, and calculate the area of the hysteresis. The sorption isotherms were determined by static method using acid solutions and adjusted different mathematical models to the experimental data by nonlinear regression analysis. The model that best fit the sorption isotherms of whole pepper and pasta was the GAB model. Then, by the method of desorption and adsorption curves integration area and the hysteresis area was calculated by the difference between the curves. According to the results it was observed that the hysteresis was smaller for the sorption

Background Polycystic ovary syndrome (PCOS) is a complex endocrine disorder that involves multiple factors. Although the etiology of PCOS is unknown, there is an involvement of sex steroid hormones in the pathophysiology of this syndrome. Therefore, polymorphisms in genes involved in the action of estrogen may contribute to a woman's susceptibility to PCOS. Aim This study aimed to evaluate the association between the polymorphisms PvuII and XbaI in the estrogen receptor alpha (ESR1) gene and the occurrence of PCOS. The study also aimed to assess the influence of these polymorphisms on the metabolic and inflammatory profiles of women with PCOS. Material and methods This case–control study included 99 women with PCOS, diagnosed according to the Rotterdam criteria, and 104 age-matched healthy women. The polymorphisms were evaluated using polymerase chain reaction–restriction fragment length polymorphism. Results No association between the ESR1 gene polymorphisms and the presence of PCOS was observed. However, we found associations between the PvuII polymorphism and C-reactive protein levels, testosterone levels, family history of diabetes, and waist circumference. The XbaI polymorphism was associated with fasting glucose and a family history of hypertension. Conclusion These polymorphisms are not associated with PCOS development, but they are involved in the phenotype of complications of the syndrome. Therefore, prior knowledge of these genomic variants might contribute to taking preventive measures that could delay the metabolic and reproductive complications commonly seen in women with PCOS.

Schiff bases m-toluene N-Salicylideneaniline (m-TOL), (B) m-nitro-N- Salicylideneaniline (m-NTR) and (C) m-methoxy-N-salicylideneaniline (m-MTX) and cerium ions were studied added to 3.5 wt.% NaCl solution and added to the hybrid film based tetraethoxysilane (TEOS) e 3-methacryloxypropyltrimethoxysilane (MPTS). The polarization measurements showed lower current densities for the steel in NaCl with m-MTX, indicating that the m-MTX may be acting as an inhibitor. The hybrid films were doped with the m-MTX, Ce (III) or Ce (IV). Electrochemical measurements of open circuit potential (EOC), polarization curves and electrochemical impedance spectroscopy (EIS), were used to evaluate the corrosion behavior of the hybrid films. According Electrochemical Impedance measurements, all hybrid films, provided protection to the carbon steel. The films doped with Ce (IV), provided greater protection than the other, which indicates that this is the most suitable dopant for use in films.

This paper presents the development of a photovoltaic (PV) system to supply electric energy to a typical rural school in the countryside of the sunny Northern East of Brazil. The system is designed to supply a rural school for up to two days, even under minimum solar radiation conditions. The solar energy is captured by PV panels and stored in lead acid batteries. The solar battery charger (A boost converter) extracts the maximum power from the PV panels for any radiation. The load is supplied through a high gain boost converter (24 Vcc to 311 Vcc) and the entire system is controlled by a microcontroller, which runs the MPP algorithm, monitors the charge state of the batteries and controls the operation of the DC/DC boost converter according to the load demand.

Este artigo descreve a validação de método analítico para determinação do acaricida amitraz em mel utilizando extração com n-hexano/acetona, cleanup em cartucho de extração em fase sólida (SPE) e análise por cromatografia a gás com detector termoiônico seletivo (GC-TSD). O método pode ser utilizado para monitorar a presença do pesticida amitraz em mel, devido aos bons parâmetros analíticos, precisão (CV80%) dentro do intervalo 100-400 ng g-1. O limite estabelecido na União Européia, pelo Committee for Veterinary Medicinal Products, para amitraz em mel (200 ng g-1) está dentro deste intervalo. A resposta do sistema analítico apresentou linearidade entre 100 e 800 ng mL-1 com coeficiente de correlação de 0,9996, limite de detecção (LD-7 ng g-1) e de quantificação (LQ-100 ng g-1). O método validado foi utilizado para avaliar a qualidade de méis comercializados na cidade de Araraquara/SP, nas quais não foram detectados resíduos de amitraz.This paper describes the validation of method for analysis of the acaricide amitraz in honey using n-hexane/acetone extraction, cleanup in cartridge of solid phase extraction (SPE) and analysis by gas chromatography with nitrogen-phosphorus detector (GC -TSD). The method can be used to monitor the presence of the pesticide amitraz in honey because of its good analytical parameters, precision (CV 80%) in the range of 100-400 ng g-1. The limit set in the European Union, by Committee for Veterinary Medicinal Products, for amitraz in honey (200 ng g-1) is within this range. The response of the analytical system was linear between 100 and 800 ng mL-1 with correlation coefficient of 0.9996, limit of detection (LD -7 ng g-1) and quantification (LQ -100 ng g-1). The sample was fortified at three concentrations 100 ng g-1, 200 ng g-1 and 400 ng g-1, giving an average recovery of 80, 88 and 92% respectively. The validated method was used to assess the quality of honey sold in the city of Araraquara/SP, in which there were no residues of amitraz.

In this work, an extended version of a quasichemical thermodynamic model is presented. The swelling behavior of crosslinked acrylamide polymer gels and N-substituted derivatives, such as N-isopropylacrylamide and N-tert-butylacrylamide has been compared to predictions from such model which takes into account the specific hydrogen bonding interactions encountered in these systems. The calculated volume transition temperature of the poly(N-isopropylacrylamide) gel is 0.8 °C lower than the experimental value and the predicted solvent volume fraction in the collapsed and swollen gel states are about 2% larger than the corresponding experimental data measured at the transition point. Applying the same energy parameters obtained from regressing poly(N-isopropylacrylamide) gel swelling pressure data, the model has also been capable to correctly represent the major features found in the swelling behavior of linear poly(N-tert-butylacrylamide) and poly(N-tert-butylacrylamide) gels, after the model parameters that characterize the molecular structure were changed in accord to each polymer repetitive unit.

The degradation of caffeine in different kind of effluents, via photo-Fenton process, was investigated in lab-scale and in a solar pilot plant. The treatment conditions (caffeine, Fe 2+ and H 2 O 2 concentrations) were defined by experimental design. The optimized conditions for each variable, obtained using the response factor (% mineralization), were: 52.0 mg L −1 caffeine, 10.0 mg L −1 Fe 2+ and 42.0 mg L −1 H 2 O 2 (replaced in kinetic experiments). Under these conditions, in ultrapure water (UW), the caffeine concentration reached the quantitation limit (0.76 mg L −1 ) after 20 min, and 78% of mineralization was obtained respectively after 120 min of reaction. Using the same conditions, the matrix influence (surface water – SW and sewage treatment plant effluent – STP) on caffeine degradation was also evaluated. The total removal of caffeine in SW was reached at the same time in UW (after 20 min), while 40 min were necessary in STP. Although lower mineralization rates were verified for high organic load, under the same operational conditions, less H 2 O 2 was necessary to mineralize the dissolved organic carbon as the initial organic load increases. A high efficiency of the photo-Fenton process was also observed in caffeine degradation by solar photocatalysis using a CPC reactor, as well as intermediates of low toxicity, demonstrating that photo-Fenton process can be a viable alternative for caffeine removal in wastewater.