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Background: Selectively targeting dopamine receptors (DRs) has been a persistent challenge in the last years for the development of new treatments to combat the large variety of diseases involving these receptors. Although, several drugs have been successfully brought to market, the subtype-specific binding mode on a molecular basis has not been fully elucidated. Methods: Homology modeling and molecular dynamics were applied to construct robust conformational models of all dopamine receptor subtypes (D1-like and D2-like). Fifteen structurally diverse ligands were docked. Contacts at the binding pocket were fully described in order to reveal new structural findings responsible for selective binding to DR subtypes. Results: Residues of the aromatic microdomain were shown to be responsible for the majority of ligand interactions established to all DRs. Hydrophobic contacts involved a huge network of conserved and non-conserved residues between three transmembrane domains (TMs), TM2-TM3-TM7. Hydrogen bonds were mostly mediated by the serine microdomain. TM1 and TM2 residues were main contributors for the coupling of large ligands. Some amino acid groups form electrostatic interactions of particular importance for D1R-like selective ligands binding. Conclusions: This in silico approach was successful in showing known receptor-ligand interactions as well as in determining unique combinations of interactions, which will support mutagenesis studies to improve the design of subtype-specific ligands.

Stargazin, a transmembrane AMPAR regulatory protein (TARP), plays a crucial role in facilitating the transport of AMPA receptors to the cell surface, stabilising their localisation at synapses and influencing their gating properties. The primary objective of this study was to investigate the effect of the V143L mutation in stargazin, previously linked to intellectual disability, on the interaction between stargazin and AMPA receptors. To achieve this, we conducted a thorough examination of eight distinct molecular dynamics simulations of AMPA receptor-stargazin complexes, each associated with different conductance levels. Through extensive analysis of complex interface structures and dynamics, we revealed that the stargazin V143L mutation had a more pronounced destabilising effect on complexes with lower conductance levels than on the conductive states of the receptor, suggesting a potential association with impaired synaptic transmission in individuals with this mutation.

The Hudson Bay Lowlands (HBL) are recognized as the second largest peatland complex in the world. Due to variability in peat thickness across a large and heterogeneous landscape, the existing carbon (C) storage estimates for the HBL may contain large uncertainty. Here, we use geospatial variables that are associated with HBL peat formation, age, accumulation, and occurrence to understand the driving factors for peat depth variability and map peat depth and C storage at 30 m spatial resolution. The estimated average peat depth of HBL is 184(±48) cm with 90% of values falling between 89 and 264 cm. Based on the spatially explicit peat depth, the HBL total C storage is estimated to be 30(±6) Pg. Distance to the coastline is the most important indicator of peat depth where the depth increases with distance further away from Hudson Bay coastline, confirming that the time since peat formation is closely related to peat depth. Plain Language Summary The Hudson Bay Lowlands (HBL) contain the second largest peatland complex in the world. We used spatial data sourced from satellite observations and geospatial information that are associated with peat occurrence, age, formation, and accumulation to estimate peat depth and carbon storage at 30 × 30 m spatial details for the entire HBL. We combined several machine learning models together in a way that improves their ability to work well on new data with a technique called “stacking,” to improve the accuracy of peat depth estimation. The estimated average peat depth was 184 cm while the entire HBL stores 30 billion tonnes of carbon. The peat depth and carbon storage information presented in this study will help monitor and assess the vulnerability of carbon storage to anticipated changes in climate, resource development, land use, and disturbances that are intensifying in the region. They are also crucial for managing and protecting this vital ecosystem, quantifying the carbon cost of resource development, and for developing ecologically sound land management practices in the region. Key Points We use stacking, an ensemble learning technique designed to mitigate overfitting, to estimate peat depth in the Hudson Bay Lowlands (HBL) The average peat depth of HBL is 184 (±48) cm with 90% of depths falling within 89–264 cm HBL stores 30 (±6) Pg carbon (C) with average value of 86 (±35) kg m−2

This article proposes the design and control of a Tara flour processing machine with the aim of increasing profitability and reducing the time required for its processing. The research presents a mechatronic system composed of two main systems: one mechanical and the other electrical-electronic. The mechanical system consists of three parts. In the first part, the feeding and dosing is carried out, where the Tara is filled and shelled. In the second part, there is the shaking process, which consists of separating the seeds from the shell. The third part refers to the grinding of the Tara, thus obtaining the final product: flour. The electric-electronic system incorporates an AtMega 328P microcontroller to regulate the speeds of the motors based on the readings of the sensors used for proper processing. The implementation of this project would reduce the production time of Tara flour in the city of Ayacucho by 75% compared to the traditional method. This demonstrates the possibility of improving the production process of Tara flour.

We evaluated the impact of environmental variability on lobster Panulirus argus and Panulirus laevicauda resources in the waters off Brazil and southern Cuba. This study also covered aspects of larval recruitment associated with the availability of fishing resources in the Southern and Northern Hemispheres. Satellite-generated environmental data were sampled from 18 stations, 6 of which were in the sea off southern Cuba, 6 of which were in the coastal region of Brazil, and 6 of which were offshore near Brazil, covering important lobster fishing grounds and phyllosoma-rich areas of ocean surface circulation along the offshore boundary. The Southern Oscillation Index (SOI) was used to quantify the global ocean–atmosphere variability. Other environmental parameters included in the analysis were the monthly coastal sea levels, surface temperature (SST), salinity, wind/current speed, chlorophyll-a (Chl-a) concentrations, rainfall (RF), and Amazon River discharge (ARD). Variations in the level of puerulus settlement, juveniles, and population harvest in the coastal region of Brazil and Cuba were used to better understand the impact of environmental variability on organisms in their larval stages and their subsequent recruitment to fisheries. The surface temperature, chlorophyll-a concentration, and wind/current patterns were significantly associated with the variability in puerulus settlement. Larger-scale processes (as proxied by the SOI) affected RF, ARD, and sea levels, which reached a maximum during La Niña. As for Brazil, the full-year landings prediction model included Chl-a concentration, SST, RF, and ARD and their association with lobster landings (LLs). The landing predictions for Cuba were based on fluctuations in the Chl-a concentration and SST.

The aim of the present work is to evaluate the effect of NaOH solution as a stress cracking agent on the thermal and tensile properties of PET and PET/ZnO composites. The solutions were applied during tensile testing and the effects were monitored by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and testing the actual mechanical properties. The rate of crystallization was increased when the samples were exposed to NaOH, as observed by both cold and melt crystallization; this is possibly due to the reduction in molar mass of the PET molecules caused by NaOH. During melting, the DSC peaks became more complex, which is probably due to the distinct macromolecular mass, as well as crystallites with different sizes and levels of perfection. According to TGA analyses, no drastic changes were observed on the thermal stability of PET due to the action of NaOH. The tensile properties were shown to decrease drastically upon exposure to NaOH, which is the main symptom of stress cracking, leading to increased fragility, as also observed in the scanning electron microscopy (SEM) images. The presence of ZnO improved PET crystallization and provided some protection against the harmful effects of NaOH.

This work investigated the effect of thermo-oxidation aging in blends of copolymer polypropylene (PPc)/recycled copolymer polypropylene (PPcr) from industrial container waste, coded as PPc/PPcr blends. All compounds were melt extruded, and the injection molded specimens were characterized by mechanical properties (tensile and impact), Fourier-transform infrared spectroscopy (FTIR), melt flow index (MFI), contact angle, heat deflection temperature (HDT), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). FTIR spectra presented bands related to the hydroperoxides and carbonyl groups, as resulted from thermo-oxidation aging. The contact angle decreased upon a thermo-oxidation aging influence, corroborating the FTIR spectra. PPcr presented higher MFI as a consequence of reprocessing. Impact strength and elongation at break were quite sensible to the thermo-oxidation aging influence and were progressively reduced upon increased time, whereas tensile strength, elastic modulus, and HDT only slightly changed. SEM images of PPc presented a higher quantity of pulled-out particles, resulted from a lower interaction between phases, i.e., polypropylene and ethylene/propylene. From the impact strength and toughness data, proper dissipation energy mechanisms were found in PPc/PPcr blends. Summing up, using PPcr contributed to minimize properties’ losses, which may be related to the stabilizer agents, whereas the described results presented great potential for the PP market, while contributing to the sustainable environment.

This work aimed to investigate the biopolyethylene (BioPE)/wood powder (WP) composites compatibilized with polyethylene-grafted maleic anhydride (PE-g-MA), using macaíba oil (OM) as a processing aid. The composites were prepared, fist, in an internal mixer and, later, the crushed flakes were molded by injection. Mechanical properties (impact, tensile, flexural and Shore D hardness), heat deflection temperature (HDT), differential scanning calorimetry (DSC), thermogravimetry (TG), water absorption, torque rheometry and scanning electron microscopy (SEM) were evaluated. The addition of 30% wood powder to the BioPE matrix increased the elastic modulus (tensile and flexural), Shore D hardness and heat deflection temperature (HDT), compared to neat BioPE. These properties were improved when 10% of the PE-g-MA compatibilizer was added, compared to neat BioPE and the non-compatibilized composite. There was a significant reduction in the torque of the composites with the addition of macaíba oil, indicating that it improved the processability. In addition, the incorporation of macaíba oil into the composites helped to reduce water absorption, as well as to increase impact strength. SEM micrographs illustrated a greater degree of interfacial adhesion when PE-g-MA and macaiba oil were added.

Membranes were assessed on a bench scale for their performance in methylene blue dye separation. The sawdust, along with Brazilian clay and kaolin, were mixed and compacted by uniaxial pressing and sintered at 650 °C. The membranes were characterized by several techniques, including X-ray diffraction, scanning electron microscopy, porosity, mechanical strength, water uptake, and membrane hydrodynamic permeability. The results demonstrated that the incorporation of sawdust not only altered the pore morphology but also significantly improved water permeation and dye removal efficiency. The ceramic membrane had an average pore diameter of 0.346–0.622 µm and porosities ranging from 40.85 to 42.96%. The membranes were applied to the microfiltration of synthetic effluent containing methylene blue (MB) and, additionally, subjected to investigation of their adsorptive capacity. All membrane variants showed high hydrophilicity (contact angles < 60°) and achieved MB rejection efficiencies higher than 96%, demonstrating their efficiency in treating dye-contaminated effluents. Batch adsorption using ceramic membranes (M0–M3) removed 34.0–41.2% of methylene blue. Adsorption behavior fitted both Langmuir and Freundlich models, indicating mixed mono- and multilayer mechanisms. FTIR confirmed electrostatic interactions, hydrogen bonding, and possible π–π interactions in dye retention.

Nowadays, there is a need to obtain eco-friendly materials, especially plastics that are responsible for most of the environmental pollution. In this regard, poly(ɛ-caprolactone) PCL biocomposites with 10wt% of the oil (O) and/or 10wt% of the flour (F) extracted from the macaíba almond were produced in order to carry out a study of this polymer biodegradation acceleration. Mechanical properties (impact, traction and flexural), differential scanning calorimetry (DSC), thermogravimetric (TGA), water absorption, contact angle and analysis by optical microscopy (OM) and scanning electronics (SEM) were evaluated. Through these analyzes, it was noted that in the PCL–O biocomposite, the oil acted as a plasticizer in the PCL and in the PCL–FO biocomposite, there was an interaction among both phases. The samples biodegradation took place in accordance with ASTM G160-03 by burying impact specimens in compost for 60 days. The PCL–F biocomposite showed a mass loss of approximately 45%, followed by PCL–FO, with a loss of approximately 25%, both compositions also presented a rough morphology, with cracks and pores presence due to biodegradation from the microorganism action. These results have shown that the flour obtained from the macaíba almond is a promising agent for accelerating the PCL biodegradation.