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The substrates of the Brazilian campos rupestres, a grassland ecosystem, have extremely low concentrations of phosphorus and nitrogen, imposing restrictions to plant growth. Despite that, this ecosystem harbors almost 15% of the Brazilian plant diversity, raising the question of how plants acquire nutrients in such a harsh environment. Here, we set out to uncover the taxonomic profile, the compositional and functional differences and similarities, and the nutrient turnover potential of microbial communities associated with two plant species of the campos rupestres-dominant family Velloziaceae that grow over distinct substrates (soil and rock). Using amplicon sequencing data, we show that, despite the pronounced composition differentiation, the plant-associated soil and rock communities share a core of highly efficient colonizers that tend to be highly abundant and is enriched in 21 bacterial families. Functional investigation of metagenomes and 522 metagenome-assembled genomes revealed that the microorganisms found associated to plant roots are enriched in genes involved in organic compound intake, and phosphorus and nitrogen turnover. We show that potential for phosphorus transport, mineralization, and solubilization are mostly found within bacterial families of the shared microbiome, such as Xanthobacteraceae and Bryobacteraceae. We also detected the full repertoire of nitrogen cycle-related genes and discovered a lineage of Isosphaeraceae that acquired nitrogen-fixing potential via horizontal gene transfer and might be also involved in nitrification via a metabolic handoff association with Binataceae. We highlight that plant-associated microbial populations in the campos rupestres harbor a genetic repertoire with potential to increase nutrient availability and that the microbiomes of biodiversity hotspots can reveal novel mechanisms of nutrient turnover.

The main aim of this study was to perform an integrative review on the toxic effects of resin-matrix cements and their products in contact with fibroblasts or mesenchymal cells. A bibliographic search was performed on PubMed using the following search terms: "cytotoxicity" AND "fibroblast" OR "epithelial" OR "mesenchymal" AND "polymerization" OR "degree of conversion" OR "methacrylate" OR "monomer" AND "resin cement" OR "resin-based cement". The initial search in the available database yielded a total of 277 articles of which 21 articles were included in this review. A decrease in the viability of mouse fibroblasts ranged between 13 and 15% that was recorded for different resin-matrix cements after light curing exposure for 20 s. The viability of human fibroblasts was recorded at 83.11% after light curing for 20 s that increased up to 90.9% after light curing exposure for 40 s. Most of the studies linked the highest toxicity levels when the cells were in contact with Bis-GMA followed by UDMA, TEGDMA and HEMA. Resin-matrix cements cause a cytotoxic reaction when in contact with fibroblasts or mesenchymal cells due to the release of monomers from the polymeric matrix. The amount of monomers released from the resin matrix and their cytotoxicity depends on the polymerization parameters.

The objective of this work was to measure the tooth root canals’ diameter, remnant dentin thickness, endodontic post to dentin distance, and resin-matrix cement layer after three types of root canal shaping. Thirty extracted human premolars were endodontically treated and groups of specimens were divided according to the cementation with two different endodontic posts as follow: A) Fibio Fiberglass Post™, Anthogyr, France; B) multi-filament GFRC (Rebilda GT™, VOCO, Germany). Cone beam computed tomography (CBCT) and conventional X-ray analyses were performed before and after the endodontic post cementation. After cementation, specimens were cross-sectioned and inspected by optical microscopy and scanning electron microscopy at magnification ranging from × 30 up to × 2000. Changes in shaping of the root canals caused a decrease in the thickness of the remnant tooth tissues. CBCT and microscopic analyses also revealed a clear variation of resin-matrix cement around the glass fiber-reinforced composite (GFRC) posts. A multi-filament GFRC post provided an adequate distribution of filaments although the resin-matrix cement revealed a high volume among the filaments. An increase in thickness and volume of resin-matrix cement was noticed at the coronal third since the fitting was compromised due to tooth anatomic variations and root canal preparation. Defects such macro-scale pores, cracks, and voids were also detected by microscopic analyses. The root canal shaping can promote a decrease in the thickness of the remnant tooth tissues that can increase the risks of clinical failures by fracture. The thickness and volume of resin-matrix cement varied around both GFRC posts and increased from the apex up to the coronal third due to the lack of fitting. Graphical Abstract

Objective The purpose of this study was to perform an integrative review on laser texturing the inner surface of lithium disilicate-reinforced glass ceramic or zirconia to increase their bond strength to resin-matrix cements. Materials and method A bibliographic review was performed on PubMed using the following search terms: “zirconia” OR “lithium disilicate” AND “laser” AND “surface” OR “roughness” AND “bond strength” AND “luting agent” OR “resin cement.” Studies published in English language until March 15, 2023, were selected regarding the purpose of this study. Results A total of fifty-six studies were identified althoug thirteen studies were selected. The findings revealed that zirconia surfaces were significantly modified after laser irradiation resulting in macro-scale aligned retentive regions with depth values ranging from 50 to 120 µm. Average roughness values of laser-textured zirconia by Er,Cr:YSGG laser (~ 0.83 µm) were quite similar when compared to grit-blasted zirconia surfaces (~ 0.9 µm) although roughness increased up to 2.4 µm depending on the laser type and parameters. Lithium disilicate-reinforced glass ceramics textured with Er:YAG revealed an average roughness of around 3.5 µm while surfaces textured using Nd:YAG laser revealed an average roughness of 2.69 µm; that was quite similar to the roughness values recorded for etched surfaces (2.64 µm). The shear bond strength (SBS) values of zirconia surfaces textured on Nd:YVO4 laser irradiation were slightly higher (~ 33.5 MPa) than those recorded for grit-blasted zirconia surfaces (28 MPa). Laser-textured zirconia surfaces on CO2 laser revealed higher SBS values (18.1 ±0.8 MPa) than those (9.1 ± 0.56 MPa) recorded for untreated zirconia surfaces. On lithium disilicate-reinforced glass ceramics, higher SBS values to resin-matrix cements were recorded for specimens textured with a combination of fractional CO2 laser irradiation and HF acid etching (~ 22–24 MPa) when compared with grit-blasted specimens (12.2 MPa). Another study revealed SBS values at around 27.5 MPa for Er:YAG-textured lithium disilicate-reinforced glass ceramics to resin-matrix cements. Conclusions The laser irradiation at high power increases the roughness of the inner surface of lithium disilicate-reinforced glass ceramic or zirconia leading to an enhanced bond strength to resin-matrix cements. Thus, the laser type and irradiation parameters can be adjusted to enhance the macro- and micro-scale retention of zirconia and glass ceramic surfaces to resin-matrix cements. Clinical relevance Alternative methods for surface modification of lithium disilicate-reinforced glass ceramic and zirconia surfaces have been assessed to provide proper morphological aspects for enhanced adhesion to resin-matrix cements. An increase in the bond strength of glass ceramics or zirconia to resin-matrix cements can improve the long-term performance of cemented prosthetic structures in the oral cavity.

The aim of this work was to perform an integrative literature review on the influence of laser irradiation on zirconia implants to enhance surface topographic aspects and the biological response for osseointegration. An electronic search was carried out on the PubMed database using the following search terms: "zirconia" AND "laser" AND "surface modification" OR "surface treatment" AND "dental implants" OR "bone" OR "osteoblast" OR "osseointegration." Of the identified articles, 12 studies were selected in this review. Results reported that the laser irradiation was capable of promoting changes on the zirconia surfaces regarding topographic aspects, roughness, and wettability. An increase in roughness was recorded at micro- and nano-scale and it resulted in an enhanced wettability and biological response. Also, adhesion, spreading, proliferation, and differentiation of osteogenic cells were also enhanced after laser irradiation mainly by using a femtosecond laser at 10nJ and 80 MHz. After 3 months of osseointegration, in vivo studies in dogs revealed a similar average percentage of bone-to-implant contact (BIC) on zirconia surfaces (around 47.9 ± 16%) when compared to standard titanium surfaces (61.73 ±16.27%), denoting that there is no significant difference between such different materials. The laser approach revealed several parameters that can be used for zirconia surface modification such as irradiation intensity, time, and frequency. Laser irradiation parameters can be optimized and well-controlled to reach desirable surface morphologic aspects and biological response concerning the osseointegration process.

Blockchain is a disruptive technology that will revolutionize the Internet and our way of living, working, and trading. However, the consensus protocols of most blockchain-based public systems show vulnerabilities and performance limitations that hinder the mass adoption of blockchain. This paper presents and compares the main proof-based consensus protocols, focusing on the security and performance of each consensus protocol. Proof-based protocols use the probabilistic consensus model and are more suitable for public environments with many participants, such as the Internet of Things (IoT). We highlight the centralization tendency and the main vulnerabilities of Proof of Work (PoW), Proof of Stake (PoS), and their countermeasures. We also analyze and compare alternative proof-based protocols, such as Proof of Elapsed Time (PoET), Proof of Burn (PoB), Proof of Authority (PoA), and Delegated Proof of Stake (DPoS). Finally, we analyze the security of the IOTA consensus protocol, a DAG-based platform suited for the IoT environment.

Carbon-based catalysts functionalized with sulfonic groups are candidates for replacing homogeneous catalysts such as H2SO4. Mainly due to their high structural stability under hydrothermal reaction conditions, their easy preparation, their efficient catalytic performance, their easy separation from the reaction medium and their low cost. In general, lignocellulosic biomass residues are common precursors used in the manufacture of carbon material, reinforcing the ecologically correct character of its production. Acid catalysts derived from biomass residues can be synthesized by two methods of insertion of sulfonic groups into their structure. The first manner is postgrafting functionalization and the second is in-situ functionalization. In this study, a solid acid catalyst was developed, which used the acai seed residue as a precursor, and the in-situ functionalization method. This sulfonation route has the advantage of carbonizing and sulfonating the material simultaneously, and avoids wasting time and energy. Catalyst samples were prepared at different time and temperature of hydrothermal treatment. The HTAS6-130 sample, simultaneously carbonized and sulfonated at 130 °C for 6 h, showed better performance in the esterification reaction of oleic acid and methanol with a 95% conversion at a reaction temperature 100 °C, reaction time of 1 h, catalyst loading of 3 wt% and 12:1 methanol to oleic acid molar ratio. The recyclability of HTAS6-130 was satisfactory, reducing conversion only 18% after the five reaction cycles. In summary, the in-situ functionalization method brought together the advantages of rapid synthesis, low energy consumption and high density of active acid sites after use in five consecutive reaction cycles.

The search for new materials that can be applied in the treatment of injured human tissues has led to the development of new dressings. Membranes have potential as dressing materials because they can be fitted to and interact with the tissue surface. In this study, we analyze the morphological properties and wettability of latex membranes, along with the incorporation of the photosensitizer methylene blue, in the context of the utility of the membranes in curative applications involving photodynamic therapy (PDT). It was observed that deposition of the photosensitizer into latex membranes increased both the surface roughness and wettability. Antifungal testing indicated that antimicrobial PDT assisted by the latex membranes incorporating methylene blue effectively inactivated Candida albicans.

Economic and social development around the world has contributed to increased energy demands, which have strained the energy supply chain. The global energy matrix depends on the exploitation of fossil fuels, which are responsible for disastrous social, political, and environmental impacts. This situation has led to the need for technological advances in the development of new sources of safe, renewable, and sustainable energy production. In recent years, biomass has gained importance among emerging sources of energy production due to its abundance and renewable nature. Therefore, this study reviews the availability and physicochemical properties of unexplored Amazonian biomass sources, which, in principle, neither compete with food production nor have disastrous environmental impacts on the Amazon forest. This review also focuses on thermochemical conversion methods for possible application of the biomasses under study to produce electricity for geographically isolated communities in the Amazon, whose electricity comes from generators powered by diesel oil, a nonrenewable and relatively expensive resource. The information provided in this article is important for the formulation of alternative and renewable energy government policies for the Amazon region, in addition to presenting a scientific study of the main biomass available in the region, including thermochemical characteristics for energy conversion.

The interest on applications where machine learning algorithms and communications are combined has been on a rising in recent years. Machine learning and neural networks are being advocated as a way of improving the performance of several functions across all layers of future communication systems. Furthermore, in applications where complexity reduction is essential for the system feasibility at the cost of an affordable performance loss, more efficient systems might be achieved with the aid of machine learning algorithms. Signal detection for multiple-input multiple-output (MIMO) systems has become a hot topic in recent years given its prominent role in fourth and fifth generations of mobile networks. However, the computational complexity in MIMO systems can become prohibitive when the number of antennas increases. Therefore, by leveraging neural networks architectures we propose a deep unfolded detector, whereby the algorithm of the probability data association (PDA) detector is adapted and enhanced by means of neural network learning capabilities. We unveil that the proposed detector is orders-of-magnitude less complex than the PDA detector, yet presenting no severe penalties in performance in terms of bit error rate (BER).

Background Recent research has shown that pregnant individuals experience weight stigma throughout gestation, including negative comments and judgement associated with gestational weight gain (GWG). Weight bias internalization (WBI) is often a result of exposure to weight stigma and is detrimental to biopsychological health outcomes. The purpose of this study was to explore WBI in pregnancy and compare scores based on maternal weight-related factors including pre-pregnancy body mass index (BMI), obesity diagnosis and excessive GWG. Methods Pregnant individuals in Canada and USA completed a modified version of the Adult Weight Bias Internalization Scale. Self-reported pre-pregnancy height and weight were collected to calculate and classify pre-pregnancy BMI. Current weight was also reported to calculate GWG, which was then classified as excessive or not based on Institute of Medicine (2009) guidelines. Participants indicated if they were diagnosed with obesity by a healthcare provider. Inferential analyses were performed comparing WBI scores according to pre-pregnancy BMI, excessive GWG, and obesity diagnosis. Significance was accepted as p Result 336 pregnant individuals completed the survey, with an average WBI score of 3.9 ± 1.2. WBI was higher among those who had a pre-pregnancy BMI of obese than normal weight (p = 0.04, η2 = 0.03), diagnosed with obesity than not diagnosed (p p Conclusions Pregnant individuals who have a higher BMI, obesity and gain excessively may experience WBI. Given that weight stigma frequently occurs in pregnancy, effective person-oriented strategies are needed to mitigate stigma and prevent and care for WBI.

In this work, the surface of commercial activated carbon was modified with the copper sulfate salt by impregnation method, aiming at the removal of reduced sulfur compounds from aqueous media. The materials were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy with energy dispersion spectroscopy, and using nitrogen gas as adsorbent, the apparent specific surface areas were determined. In addition, the semiquantitative analysis to explore the surface area was performed using methylene blue a ‘molecular probe.’ For the adsorption, was used l-cysteine as the model adsorbate. After the impregnation of activated carbon, the presence of copper in the forms of copper oxide and metallic copper was confirmed. The mapping of functional groups demonstrated the carbonaceous characteristic of the material. The photomicrographs showed crystals on the surface of the activated carbon impregnated with copper and revealed a copper atomic content of 16.8% w/w. However, the impregnation caused a reduction in the apparent specific surface, probably due to the clogging of the pores with the impregnation salt. On the other hand, the results of adsorption tests showed an increase in l-cysteine removal with impregnation, ranging from 76 to 93%. The results suggest that the adsorbent impregnated with copper is considered promising for the removal of compounds with reduced sulfur.

In this study, the modulation of enzymatic biocatalysts were developed by the use of lipase B from Candida antarctica covalently immobilized on an eco-friendly support, cashew apple bagasse, activated with 10% glycidol-ethylenediamine-glutaraldehyde (GEG) under different immobilization strategies (5 mM or 100 mM ionic strength and in absence or presence of 0.5% (v/v) Triton X-100). The biocatalysts were characterized for thermal and organic solvents stabilities and compared with the soluble enzyme. The biocatalysts were then applied to the hydrolysis of the rac-indanyl acetate (2:1 ratio enzyme/substrate) at pH 7.0 and 30 °C for 24 h. For all the strategies evaluated, GEG promoted kinetic resolution of rac-indanyl acetate with maximum conversion (50%) and led to (R)-indanol with excellent enantiomeric excess (97%), maintaining the maximum conversion for five consecutive cycles of hydrolysis. Therefore, the use of cashew apple bagasse has proved to be a promising eco-friendly support for enzyme immobilization, since it resulted in stable biocatalysts for enzymatic kinetic resolution.

Limited research has measured the effect of physical activity (PA) interventions on health-related quality of life (HRQoL) among pre-school-aged children. This study evaluates the effect of the Activity Begins in Childhood (ABC) cluster-randomized controlled trial designed to increase PA in the ages 3–5 years on HRQoL. This was a cluster-randomized controlled trial where the intervention group included PA education delivered to daycare providers only, or daycare providers and parents. In the current study, the two PA intervention groups were combined. The comparator group received standard daycare curriculum (COM). A total of 215 children were included (PA n = 161, COM n = 54). Parents completed the proxy Pediatric Quality of Life Inventory Generic Core Scale (PedsQL™ 4.0) to measure HRQoL at baseline and the end of the 6-month trial. HRQoL scores were analyzed as physical, psychosocial, and total domains. Baseline and 6-months measurements were compared for PA and COM groups, and mean changes in scores (95% confidence intervals) were measured using absolute values. No between-group differences were observed for the physical (p = 0.17), psychosocial (p = 0.95) or total scores (p = 0.20). Paired comparisons showed that only the PA group improved psychosocial- (PA mean difference = 2.18 (0.20, 4.15), p = 0.03; COM mean difference = 2.05 (− 1.03, 5.13), p = 0.19) and total-HRQoL scores (PA mean difference = 2.83 (1.83, 3.84), p

Creating energy storage devices from biomass waste has great scientific and industrial significance by providing an eco-friendly and sustainable alternative to reuse biowaste. This study demonstrates the production of high-performance supercapacitor electrodes using acai seed as a precursor for creating carbon materials. Porous carbons were synthesized by carbonization and subsequent KOH activation to generate microporosity then mesoporosity upon further activation. The materials displayed large specific surface areas and total pore volumes, with tunable pore structures depending on the degree of activation. The biomass-derived electrodes exhibited high specific capacitances of 346 F g−1 at 1 mA cm−2 and good electrochemical stability in which 88% of the initial capacitance was retained after 5000 charges/discharges cycles at 7 mA cm−2 in 1 M KOH electrolyte. These results place these materials among the best biomass-derived supercapacitors reported thus far. This study provides a great alternative for the management of the large-scale biowaste, acai seed.

The final disposal of hazardous waste, such as cigarette waste, cannot be the same as conventional urban solid waste because it has considerable levels of toxic substances. In this context, this work presents a methodology for the application of cigarette waste in clay mixtures at incorporation ratios of 0%, 2.5%, 5%, 7.5% and 10%. 50 × 6 mm cylindrical specimens were tested in compression, water absorption and shrinkage after firing at 900 °C. Even with a reduction in the evaluated parameters, it was proved that the use of up to 5% of cigarette waste is technically feasible. Gas chromatogram, dilatometry, mercury intrusion porosimetry and scanning electron microscopy tests were also performed. These tests helped to prove that the loss of mechanical properties occurred due to the increase of the porosity of the red ceramic artifacts with the incorporation of cigarette waste, as a result of the combustion of the organic matter present in the waste. However, this combustion is also beneficial because it increases energy efficiency during the burning of ceramic products. The feasibility of using up to 5% cigarette waste in ceramic materials has been proven, provided that the waste is dispersed and homogenized within the clay in the production of the raw materials.

We use the maps elaborated within the Mexican Mangrove Monitoring System (MMMS) project of the National Commission for Knowledge and Use of Biodiversity (CONABIO) to analyze the changes in mangrove area distribution during the last 45 years, within the framework of the coastal regional characteristics in Mexico. We found that 19% of the primary mangrove area identified in 1970/1980 was lost and that 9.4% was gained as secondary mangrove forests due to the colonization of new or disturbed areas. Using location and residence stability indexes, we identified two main change dynamics within three periods (1970/1980–2005, 2005–2010 and 2010–2015): (1) the dominant effect of climate change, especially in northwest Mexico and (2) the dominant effect of anthropic activities, mainly in the Gulf of Mexico. Significant differences in changes in the area of mangroves between regions over time highlight the relevance of more detailed and local studies to understand the processes leading to the degradation or conservation of mangroves.

This paper presents the results of the numerical investigation of a hypersonic air flow in two different types of intake configurations of a scramjet engine. These configurations, referred as the internal compression intake system and the mixed compression intake system, are designed to operate at an altitude of 30 km and with an inlet air flow corresponding to a Mach number of 6.8. In order to investigate the general behavior of the flow, a set of RANS simulations were performed for both cases. The results show relevant details of the flow such as the proper capturing of the shock wave fronts, the engine compression performance and the spatial development of the flow through the engine. In general, a substantial amount of similarities concerning the flow behavior are observed when both configurations are directly compared. A quantitative analysis centered in specific parameters describing the compression of the inlet flow, e.g., the adiabatic compression efficiency, indicates minor differences when these parameters are assessed. Nevertheless, additional considerations reveal a greater versatility of the internal intake system; for instance, an analysis of the spatial development of the boundary layer flow, as quantified by the velocity profiles of the flow extracted at different locations, suggests better mixing properties in comparison with the mixed intake system. The latter effect is desirable since mixing enhancement in the combustion chamber can help to achieve stable conditions for supersonic combustion.

In this study, the energy potential of buriti (Mauritia flexuosa L. f.) and inaja (Attalea maripa Aubl. Mart.) seeds for pyrolysis was evaluated via thermogravimetric analysis in the temperature range of 30–900 °C at heating rates of 5, 10, 15, and 20 °C min−1 in an inert atmosphere. Five isoconversional methods were used, i.e., Ozawa-Flynn-Wall, Kissinger–Akahira–Sunose, Starink, Tang, and Vyazovkin, to determine the kinetic and thermodynamic parameters. The mean activation energies were 146.84, 144.99, 144.21, 145.28, and 145.36 kJ mol−1 for the buriti seed and 115.88, 112.01, 111.52, 112.37, and 112.38 kJ mol−1 for the inaja seed, respectively. The values of the high heating value (HHV) of buriti and inaja seeds were similar to lignocellulosic biomasses and are estimated at 21.3 and 18.0 MJ kg−1, respectively. The thermodynamic parameters (ΔG, ΔH, and ΔS) and the reaction mechanism using the master plot method were determined. Furthermore, the evolution of the gas during pyrolysis was performed by thermogravimetry coupled with mass spectrometry (TG/MS). The main gaseous products evolved during active pyrolysis were H2O, CO2, CO, aldehydes, esters, carboxylic acids, and saturated and unsaturated hydrocarbons, which can be converted into energy and valuable chemicals. This dataset contributes to investigating these biomasses as candidates for applications in the pyrolysis process.

We study the convergence of a modified proximal point method for DC functions in Hadamard manifolds. We use the iteration computed by the proximal point method for DC function extended to the Riemannian context by Souza and Oliveira (J Glob Optim 63:797–810, 2015) to define a descent direction which improves the convergence of the method. Our method also accelerates the classical proximal point method for convex functions. We illustrate our results with some numerical experiments.

Huanglonbing, or citrus greening, is the most serious disease of citrus which cause large economic losses. One of the strategies to avoid the spread of the disease is the control of Diaphorina citri psyllid, its insect vector, by the application of insecticides. Development of nanoinsecticides, which are less harmful to the environment and more efficient (in terms of cost and performance) than the existing formulations, is a current challenge. In this work, nanocarriers composed of chitosan–tripolyphosphate (by ionic gelification approach) and poly-e-caprolactone (PCL)–chitosan (by double-emulsion–solvent evaporation method) for thiametoxam insecticide were developed and characterized. Toxicological assessments using Raphidocelis subcapta, Artemia salina and Caernohabditis elegans were performed comparing PCL–chitosan nanoparticle and PCL–chitosan loaded thiamethoxam in comparison to commercial pesticide. The nanoparticles obtained from optimized conditions resulted in positive charged nanoparticles, with medium dispersity. The double-emulsion method resulted in smaller nanoparticles (313.5 ± 7 nm) and increased encapsulation efficiency (36.6 ± 0.2%) in comparison to chitosan–tripolyphosphate nanoparticles. The lower encapsulation efficiency was observed in chitosan–tripolyphosphate, impairing agricultural applications. The EC50 values (mg L−1) of Raphidocelis subcapitata and C. elegans obtained for poly-e-caprolactone with thiamethoxam were 56.15 (18.91–131.21) and 66.07 (1.20–274.14), respectively, and poly-e-caprolactone without thiamethoxam 94.26 (22.42–166.10) and 214.63 (139.08–494.3), respectively. No toxicity was found in Artemia salina. Our results indicate that nanoparticles (with and without thiamethoxam) were more toxic to soil organisms (C. elegan) than commercial formulations.

In this paper, we perform the steepest descent method for computing Riemannian center of mass on Hadamard manifolds. To this end, we extend convergence of the method to the Hadamard setting for continuously differentiable (possible nonconvex) functions which satisfy the Kurdyka–Łojasiewicz property. Some numerical experiments computing $$L^1$$ and $$L^2$$ center of mass in the context of positive definite symmetric matrices are presented using two different stepsize rules.

The objective of this research was to evaluate the Anadenanthera peregrina wood cultivated in five spacing and pyrolyzed in two different heating rates. Three trees were collected from each spacing (3 × 2, 3 × 3, 4 × 3, 4 × 4 and 5 × 5 m), and samples were taken for the determination of the physical and chemical properties of the wood, the pyrolysis under the two heating rates (1.67 and 0.83 °C min−1) and the subsequent analysis of the charcoal produced. Planting spacing did not influence the properties of A. peregrina wood. The heating rate influenced the charcoal properties, interacting with the spacing for the ash content and apparent density, yields of pyroligneous liquid and non-condensable gases.

Biomass has great potential for the production of fuels with high volatility and reactivity. In the Amazon region, biomass waste is mainly from fruits, which generate a large amount of stone and shell. Therefore, there is a need for technology to advance the use of renewable energy. This study aims to evaluate the combustion properties of biomass waste by using thermogravimetric analysis (TG-DTG). Five residues were used: acai stone, cocoa shell, coconut shell, cupuacu shell and Brazil nut shell. TG curves show the mass loss from room temperature to 140 °C, which is related to the removal of moisture. The second mass loss is ascribed to volatile matter in the temperature range of 140–400 °C, and the third mass loss from 400 to 600 °C is due to the decomposition of fixed carbon. By evaluating the thermal properties such as volatile matter, moisture, ignition temperature and mean reactivity index, it can be said that the coconut shell sample has combustion features that lead to its better use as fuel, while the acai stone biomass presents unsatisfactory combustion properties among the biomasses studied. The higher heating value is an important property which defines the energy content and efficient use of these fuels, and thus, for the biomass samples, the following order of higher heating value can be observed: Brazil nut shell, acai stone, cupuacu shell, cocoa shell and coconut shell.

Natural and anthropogenic hazards have the potential to impact all aspects of society including its economy and the environment. Diagnostic data to inform decision-making are critical for hazard management whether for emergency response, routine monitoring or assessments of potential risks. Imaging spectroscopy (IS) has unique contributions to make via the ability to provide some key quantitative diagnostic information. In this paper, we examine a selection of key case histories representing the state of the art to gain an insight into the achievements and perspectives in the use of visible to shortwave infrared IS for the detection, assessment and monitoring of a selection of significant natural and anthropogenic hazards. The selected key case studies examined provide compelling evidence for the use of the IS technology and its ability to contribute diagnostic information currently unattainable from operational spaceborne Earth observation systems. User requirements for the applications were also evaluated. The evaluation showed that the projected launch of spaceborne IS sensors in the near-, mid and long term future, together with the increasing availability, quality and moderate cost of off the shelf sensors, the possibilities to couple unmanned autonomous systems with miniaturized sensors, should be able to meet these requirements. The challenges and opportunities for the scientific community in the future when such data become available will then be ensuring consistency between data from different sensors, developing techniques to efficiently handle, process, integrate and deliver the large volumes of data, and most importantly translating the data to information that meets specific needs of the user community in a form that can be digested/understood by them. The latter is especially important to transforming the technology from a scientific to an operational tool. Additionally, the information must be independently validated using current trusted practices and uncertainties quantified before IS derived measurement can be integrated into operational monitoring services.

In this paper, we propose a Bregman regularized proximal point method for solving monotone equilibrium problems. Existence and uniqueness results as well as convergence of the sequence to a solution of an equilibrium problem is analyzed. We assume a coercivity condition on the Bregman function weaker than the one considered in the literature on equilibrium problems with Bregman regularization. Numerical experiments illustrate the efficiency of the method.

The Co-doped molybdenum carbides are considered promising catalytic materials. These materials have been employed in photocatalytic degradation reactions, which is the emission of radiation from sunlight or artificial light for the activation of the material to occur. In this work, we have studied the behavior of the Mo2C and Co-doped Mo2C, with Co concentration of 5% and 10%, through the photodegradation of the Maxilon Blue GRL 300 basic dye under tungsten light irradiation, varying the pH of the solutions. The carbide materials were characterized by X-ray diffraction, scanning electron microscopy coupled to EDS, and determination of the band gap energy by NIR Cary model 5G UV–visible spectrophotometer. Concerning the photocatalysis tests, the resulting solutions were analyzed by UV–visible spectroscopy, to calculate the final concentrations of the samples. This experimental procedure led to a decrease in carbonation temperature usually employed on the synthesis, as well as the modification/control of the photodegradation of the Maxilon Blue GRL 300 by manipulating the pH. The significant reaction yield results were for the acid medium molybdenum carbide sample, achieving a yield of 90.5% at the final concentration of the dye solution.

To evaluate the influence of the pre-treatment with 2.5% nanoparticulate chitosan (2.5% NanoChi) solution on eroded dentin before the restorative dental treatment. The sample consisted of 22 patients (age between 33 and 52 years) with shallow or medium erosion lesions located in two homologous teeth. The teeth were randomly assigned according to dentin treatment: with 2.5% NanoChi and without with chitosan (control). The NanoChi were applied immediately after acid etching. The teeth were restored with Single Bond Universal (3 M) and Charisma resin (Kulzer). Analyzes were done using modified USPHS (retention, secondary caries, marginal adaptation, and sensitivity) and photographic (color, marginal pigmentation, and anatomical form) criteria at 7 days (baseline) and 1 year. Population demographics, Kaplan–Meier estimates and log-rank test (Mantel–Cox) were calculated for 1 year (α = 0.05). No significant difference was found in the survival rates between groups (p > 0.05) at 7 days and 1 year after treatment. After 7 days, 100% of the restorations were scored as Alpha on all criteria. After 1 year, 91% of the NanoChi restorations were scored as Alpha and 9% as Charlie for the retention, marginal adaptation, and anatomical form criteria, while 86% of the control restorations (without NanoChi) received the Alpha score and 14% received the Charlie. Secondary caries, sensitivity, color, and marginal pigmentation criteria were scored as Alpha in 100% of the restorations. The biomodification of eroded dentin with 2.5% NanoChi did not influence the survival of the restorations after 1 year. The application of 2.5% NanoChi on eroded dentin did not increase failures of resin restorations after 1 year and it can be used as a pre-treatment solution.

In this work, we present a computational investigation on the photoexcitation of indigo carmine (IC). Physical insights regarding IC photoexcitation and photolysis were obtained from a fundamental perspective through quantum chemistry computations. Density functional theory (DFT) was used to investigate the ground state while its time-dependent formalism (TD-DFT) was used for probing excited state properties, such as vertical excitation energies, generalized oscillator strengths (GOS), and structures. All the computations were undertaken using two different approaches: M06-2X/6-311+G(d,p) and CAM-B3LYP/6-311+G(d,p), in water. Results determined using both methods are in systematic agreement. For instance, the first singlet excited state was found at 2.28 eV (with GOS = 0.4730) and 2.19 eV (GOS = 0.4695) at the TD-DFT/CAM-B3LYP/6-311+G(d,p) and TD-DFT/M06-2X/6-311+G(d,p) levels of theory, respectively. Excellent agreement was observed between the computed and the corresponding experimental UV-Vis spectra. Moreover, results suggest IC undergoes photodecomposition through excited state chemical reaction rather than via a direct photolysis path. To the best of our knowledge, this work is the first to tackle the photoexcitation, and its potential connections to photodegradation, of IC from a fundamental chemical perspective, being presented with expectations to motivate further studies.

Giant fractional Shapiro steps have been observed in Josephson junction arrays as resulting from magnetic flux quantization in the two-dimensional array. We demonstrate experimentally the appearance of giant fractional Shapiro steps in anisotropic Josephson junction arrays as unambiguous evidence of a skewed current phase relationship. Introducing anisotropy in the array results in a giant collective high frequency response that reflects the properties of a single junction, as evidenced by the observation of a Fraunhofer like magnetic field dependence of the total critical current of the system. The observed phase dynamics can be perfectly captured within an extended resistively shunted Josephson junction model. These results directly indicate the potential of Josephson junction arrays to explore the current phase relation in a very broad frequency range (down to 50 MHz) and in a wide variety of novel link materials exhibiting non-conventional current phase relationships. Giant fractional Shapiro steps have been observed in Josephson junction arrays as resulting from magnetic flux quantization in the two-dimensional array. Here, the authors demonstrate the observation of giant fractional Shapiro steps in an anisotropic Josephson junction array, as unambiguous evidence of a skewed current phase relationship.

Made available in DSpace on 2019-10-04T12:42:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-11-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) National Institute for Science and Technology on Organic Electronics FAPEMAT CENAPAD/SP Experimental and theoretical techniques are commonly utilized to characterization of materials. In this work, TiO2 nanoparticles (TiO2NP) from anatase and rutile were analyzed by X-ray diffraction (XRD), that was used to follow the structural evolution of the amorphous precipitate, and microstructure analysis was realized with Rietveld refinement. By Rietveld refinements, the crystallographic image file are generated for each sample to be able to perform simulations of the material structure. In addition, density functional theory was used to analyze electronic structures, several adsorptions of the H2O molecule onto TiO2 were performed, using -H was displaced in steps 0.01 angstrom and calculation/optimization energies were obtained up to cleavage H-O-H and O-H formation, taking into account photocatalytic mode of electron density distribution isosurfaces. Univ Fed Mato Grosso, LCM, Dept Quim, Cuiaba, MT, Brazil Univ Estadual Paulista, Fac Engn, Ilha Solteira, SP, Brazil Univ Sao Paulo, Inst Fis Sao Carlos, Sao Carlos, SP, Brazil Univ Estadual Paulista, Fac Engn, Ilha Solteira, SP, Brazil CNPq: 454704/2014-3 CNPq: 152036/2016-4 CNPq: 427161/2016-9 FAPESP: 2011/11065-0 National Institute for Science and Technology on Organic Electronics: CNPq 573762/2008-2 National Institute for Science and Technology on Organic Electronics: FAPESP 2008/57706-4 FAPEMAT: 214599/2015 FAPEMAT: Pronem/569157-2014 CENAPAD/SP: Proj650

We study the convergence of exact and inexact versions of the proximal point method with a generalized regularization function in Hadamard manifolds for solving scalar and vectorial optimization problems involving Lipschitz functions. We consider a local dominance property of the directional derivative of the objective function over the regularization term in order to obtain that cluster points of the sequence are stationary points. Under an additional assumption, we prove that every cluster point of the sequence is a minimizer in the scalar case and a weak efficient point in the vectorial case. Our results extend some of the existing ones in the literature about optimization on manifolds.

Stemphylium solani is an important foliar pathogen that infects many agricultural plants, especially solanaceous plants. The difficulty inducing sporulation in pure culture is a limiting factor for research on the different pathosystems involving S. solani. In this study, the influence of the culture medium, photoperiod with alternating temperatures, Petri dish cover materials (glass, polystyrene and PVC film) and stress factors of the colonies were investigated in the conidia production. Six sequential assays were performed with four isolates of S. solani, obtained from tomato plants. The inoculum produced was evaluated for infectivity on tomato plants under greenhouse conditions. The addition of fresh tomato juice to the agar medium and incubation temperatures of approximately 25 °C favoured mycelial growth. The ability to sporulate in vitro varied with the isolate, but in general the conidia production was significantly higher in V8 medium at 25 °C 6 h−1 light and 10 °C 18 h−1 of darkness. Sporulation was lower in glass Petri dishes but higher in transparent polystyrene dishes. The methodology allowed the production of viable and infective inoculum in sufficient quantity to inoculate plants under experimental conditions.

We study some conditions for a monotone bifunction to be maximally monotone by using a corresponding vector field associated to the bifunction and vice versa. This approach allows us to establish existence of solutions to equilibrium problems in Hadamard manifolds obtained by perturbing the equilibrium bifunction.

In this work, we present a computational study on the antioxidant potential of myricetin 3-O-α-L-rhamnopyranoside (Compound M3) and myricetin 4′-O-α-L-rhamnopyranoside (Compound M4′). Structural parameters, bond dissociation enthalpies (BDEs), ionization potentials (IPs), proton dissociation enthalpies (PDEs), proton affinities (PAs), and electron transfer enthalpies (ETEs), which are properties connected with different mechanisms related to antioxidant activity, were determined using density functional theory (DFT) with B3LYP, LC-ωPBE, M06-2X, and BMK functionals along with the 6-311G(d,p) and 6-311+G(d,p) basis sets in the gas phase, water, and pentylethanoate. The values obtained were compared with results previously available in the literature for myricetin (the parent molecule and a well-known antioxidant) and myricetin 3,4′-di-O-α-L-rhamnopyranoside (Compound M3,4′). As the BDEs are considerably lower than the IPs, the HAT mechanism is preferred over SET for the compounds M3 and M4′. The present study indicates Compound M3 as having its lowest bond dissociation enthalpy from the several different OH groups with similar value to the lowest for myricetin (74.72 kcal/mol versus 74.8 kcal/mol, respectively, at the B3LYP/6-311G(d,p) level of theory in the gas phase) and, thus, presenting antioxidant potential as good as its parent molecule. On the other hand, Compound M4′ presented 78.97 kcal/mol as the lowest BDE at the B3LYP/6-311G(d,p) level of theory in the gas phase, that is very close to the 78.34 kcal/mol computed using the same approach for Compound M3,4′. Therefore, the present investigation indicated Compound M4′ as being a slightly inferior antioxidant (with antioxidant potential comparable to Compound M3,4′) than Compound M3. In addition, the inclusion of the sugar moiety studied here in the position 4′-ArOH of myricetin seems to have a more marked impact (downward) on the antioxidant activity than the glycosylation in the position 3-ArOH.