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Deep Learning models have presented promising results when applied to Agriculture 4.0. Among other applications, these models can be used in disease detection and fruit counting. Deep Learning models usually have many layers in the architecture and millions of parameters. This aspect hinders the use of Deep Learning on mobile devices as they require a large amount of processing power for inference. In addition, the lack of high-quality Internet connectivity in the field impedes the usage of cloud computing, pushing the processing towards edge devices. This work describes the proposal of an edge AI application to detect and map diseases in citrus orchards. The proposed system has low computational demand, enabling the use of low-footprint models for both detection and classification tasks. We initially compared AI algorithms to detect fruits on trees. Specifically, we analyzed and compared YOLO and Faster R-CNN. Then, we studied lean AI models to perform the classification task. In this context, we tested and compared the performance of MobileNetV2, EfficientNetV2-B0, and NASNet-Mobile. In the detection task, YOLO and Faster R-CNN had similar AI performance metrics, but YOLO was significantly faster. In the image classification task, MobileNetMobileV2 and EfficientNetV2-B0 obtained an accuracy of 100%, while NASNet-Mobile had a 98% performance. As for the timing performance, MobileNetV2 and EfficientNetV2-B0 were the best candidates, while NASNet-Mobile was significantly worse. Furthermore, MobileNetV2 had a 10% better performance than EfficientNetV2-B0. Finally, we provide a method to evaluate the results from these algorithms towards describing the disease spread using statistical parametric models and a genetic algorithm to perform the parameters' regression. With these results, we validated the proposed pipeline, enabling the usage of adequate AI models to develop a mobile edge AI solution. [ABSTRACT FROM AUTHOR]

Background: Vitamin A deficiency (VAD) and anemia are the most prevalent nutritional deficiency in children globally. The dried blood spot (DBS) method has been used in prevalence studies of VAD and anemia in different age groups. However, it has not yet been validated for children.Objectives: This study aimed to assess the reproducibility and validity of DBS in the diagnosis of VAD and anemia in preschoolers.Methods: Venous and capillary blood samples were collected from a representative sample of children <5 y old who attended the public health system in Rio de Janeiro. Serum retinol and hemoglobin were measured in 235 and 182 children, respectively. Serum retinol was measured with HPLC and hemoglobin was measured with spectrophotometry in samples of venous (gold standard) and capillary blood (test method, DBS). DBS reproducibility was assessed with the intraclass correlation coefficient (ICC), κ, and prevalence-adjusted and bias-adjusted κ (PABAK). DBS validity was assessed with sensitivity, specificity, accuracy index (AI), positive predictive value (PPV), and negative predictive value (NPV).Results: DBS showed very good reproducibility for serum retinol (ICC = 0.94, κ = 0.83, PABAK = 0.76) and very good/good reproducibility for hemoglobin (ICC = 0.86, κ = 0.69, PABAK = 0.69). Prevalence rates for VAD by the reference and test methods were 11.5% and 11.9%, respectively, whereas the anemia rates were 19.2% and 46.2%. The test method showed low sensitivity (33%) and PPV (32%) and high specificity (91%) and NPV (92%) for serum retinol. For hemoglobin, the test method showed fair sensitivity (71%), low PPV (30%), fair specificity (60%), and high NPV (90%). AI was 83% for VAD and 62% for anemia.Conclusions: The results suggest that DBS is adequate for the diagnosis of VAD in preschool children, but not for anemia. [ABSTRACT FROM AUTHOR]

We propose a new way to assess the output signal of a quantum-well infrared photodetector (QWIP). Instead of measuring the photocurrent produced by the device, as usually done, we show that the noise induced by the absorption process can be used to generate a useful detection signal. We built a simple electronic circuit able to quantify the noise of an AlGaAs/GaAs QWIP that was intentionally designed to produce no photocurrent at all, and we demonstrated that such a circuit was able to generate a strong output signal whenever an infrared radiation of a specific wavelength was shed on the detector. This concept opens new possibilities for the design of novel types of photodetection systems. [ABSTRACT FROM AUTHOR]

Introdução: Os bifenilos policlorados (PCBs) são compostos sintéticos que se bioacumularam e contaminaram o ecossistema global. Estudos identificaram o cérebro como um alvo vulnerável para esses compostos. Substâncias com ação no Sistema Nervoso Central (SNC), como os polifenóis, têm demonstrado efeito neuroprotetor. Nosso grupo mostrou que o extrato de folhas frescas de Alpinia zerumbet (AZE), rico em polifenóis, possui efeitos antioxidantes e anti-inflamatórios em modelo de hipertensão. Objetivo: O estudo teve como objetivo avaliar se o AZE é capaz de prevenir a neurotoxicidade e as alterações locomotoras induzidas pelo PCB126 em camundongos C57BL/6 adultos. Método: Camundongos C57BL/6 machos foram divididos em quatro grupos: controle (Cont), Cont+AZE (50mg/kg/dia na água de beber), PCB (2mg/Kg/uma vez por semana), PCB+AZE (2mg/Kg/uma vez por semana; 50mg/Kg/dia intraperitoneal), durante quatro semanas. Ao final do experimento, os animais realizaram o teste do labirinto em cruz elevado e foram eutanasiados. O estresse oxidativo foi avaliado por espectrofotometria em homogenato de tronco encefálico, cerebelo, mesencéfalo e córtex esquerdo. Os dados estão expressos como média e erro padrão da média. As diferenças entre os grupos foram analisadas por análise de variância (ANOVA) seguidas pelo pós-teste de Tukey. Resultados: Houve uma diminuição (p<0,05) da atividade locomotora no grupo PCB em comparação aos grupos Cont e Cont+AZE, que foi prevenida pelo AZE no grupo PCB+AZE. O tempo nos braços abertos não foi estatisticamente diferente entre os grupos. No tronco encefálico, o grupo PCB apresentou aumento (p<0,05) da peroxidação lipídica em relação ao grupo Cont+AZE, o que foi prevenido pelo tratamento com AZE no grupo PCB+AZE. Não houve diferença estatística na atividade da enzima antioxidante catalase (CAT) entre os grupos. Houve diminuição (p<0,05) da atividade antioxidante da enzima superóxido dismutase (SOD) no grupo PCB em relação aos grupos Cont e Cont+AZE, que foi prevenida pelo tratamento com AZE no grupo PCB+AZE. No cerebelo, o dano oxidativo não foi estatisticamente diferente entre os grupos. O tratamento com AZE preveniu a redução (p<0,05) da atividade da CAT no grupo PCB+AZE em comparação aos grupos Cont+AZE e PCB. O grupo PCB apresentou diminuição (p<0,05) da atividade de SOD em relação ao grupo Cont+AZE, o que foi prevenido pelo tratamento com AZE no grupo PCB+AZE. No mesencéfalo, não houve diferença estatística na peroxidação lipídica e na atividade antioxidante da SOD entre os grupos. No entanto, o grupo PCB apresentou diminuição (p<0,05) da atividade da CAT em relação ao grupo Cont, o que foi prevenido pelo tratamento com AZE no grupo PCB+AZE. No córtex esquerdo, a peroxidação lipídica foi aumentada (p<0,05) no grupo PCB em comparação ao grupo Cont+AZE. O tratamento com AZE preveniu esse aumento no grupo PCB+AZE. As atividades da CAT e da SOD não diferiram entre os grupos. Conclusão: Nossos resultados preliminares demonstraram que o AZE preveniu o desenvolvimento de déficits locomotores induzidos pelo PCB e não causou comportamento do tipo ansioso. Além disso, o extrato também preveniu o dano oxidativo e a redução da atividade antioxidante em diferentes regiões do cérebro, sugerindo um efeito neuroprotetor. [ABSTRACT FROM AUTHOR]

We present anisotropic nonparabolic position-dependent effective-mass calculations of the bound energy levels of electrons confined in lens-shaped InxGa1-xAs quantum dots embedded in a GaAs matrix. The strain and In gradient inside the quantum dots and their wetting layer (due to the strong In segregation effect present in the InxGa1-xAs/GaAs system) were taken into account. The bound eigenstates and eigenenergies of electrons in a finite 3D confinement potential were determined by the full numerical diagonalization of the Hamiltonian. The quantum dots and their wetting layer were sliced into a finite number of monolayers parallel to the substrate surface, each one with a specific In concentration, in order to be able to reproduce any composition profile along the growth direction. A comparison between the eigenenergies of the 'pure' InAs quantum dots and the quantum dots with an inhomogeneous In content indicates that In segregation dramatically affects their electronic structure and must be taken into account if one wishes to accurately simulate the real optoelectronic properties of such nanostructures. [ABSTRACT FROM AUTHOR]

Whiteflies cause significant crop losses through direct sap feeding, inducing plant physiological disorders and promoting the growth of sooty mold. Moreover, whiteflies can indirectly harm plants by transmitting plant viruses, particularly begomoviruses and criniviruses, resulting in severe viral disease epidemics. This study aimed to evaluate the physiological characteristics of susceptible and resistant soybean cultivars to B. tabaci. The experiments were conducted in a greenhouse. Eleven soybean cultivars were selected and infested with 100 adults of B. tabaci at the V3 stage. The evaluation of photosynthetic parameters, such as photosynthetic rate, leaf transpiration, stomatal conductance, and internal CO2 concentration, revealed that B. tabaci infestation influenced gas exchange in soybean plants. The photosynthetic rate was higher in cultivars AS3810 and M8349 during the V6 stage. Infestations caused alterations in photosynthetic parameters, suggesting increased energy demand to maintain photosynthetic activity. However, the response to infestation varied among the different cultivars, indicating varying levels of resistance and tolerance to the whitefly's damage. Furthermore, the infestation had a more notable impact during the vegetative phenological stage. In summary, infestation by B. tabaci has a discernible impact on the physiology of soybean plants, resulting in alterations in gas exchange parameters and water use efficiency. The reaction to infestation exhibited variations among different soybean cultivars, indicating potential differences in resistance to the pest. This study underscores the significance of assessing the physiological consequences of whitefly infestations on soybean crops. [ABSTRACT FROM AUTHOR]

In this work we studied the transport properties of a two-dimensional electron gas (2DEG) in a series of GaAs/InGaAs delta-modulation-doped quantum wells, in which an InAs layer was located in the vicinity of the electron channel. We observed that, even after illumination, all samples exhibited a total free-electron concentration slightly lower than the one measured in a reference sample (without the InAs layer), an effect that was attributed to the transfer of carriers from the 2DEG to the surface states. Our data also provided evidence that strain fields in and around the quantum dots act as additional scattering sources for the 2DEG. [ABSTRACT FROM AUTHOR]

Photoluminescence (PL) spectroscopy and atomic-force microscopy (AFM) were used to investigate the size evolution of InAs quantum dots on GaAs(001) as a function of the amount of InAs material. Different families of islands were observed in the AFM images and unambiguously identified in the PL spectra, together with the signal of the wetting layer. PL measurements carried out at low and intermediate temperatures showed a thermal carrier redistribution among dots belonging to different families. The physical origin of this behavior is explained in terms of the different temperature dependence of the carrier-capture rate into the quantum dots. At high temperatures, an enhancement of the total PL-integrated intensity of the largest-sized quantum dots was attributed to the increase of diffusivity of the photogenerated carriers inside the wetting layer. [ABSTRACT FROM AUTHOR]

Crabs are important predators of inter-tidal ecosystems, controlling the abundance and distribution of their prey populations. Often the same crab species occupies several habitats and, although their effects on prey have been quantified across habitats, crabs' dietary and morphological responses to differing environmental influences have been overlooked. Here, we used the crabs Eriphia verrucosa and Pachygrapsus marmoratus as model species to examine differences in claw morphometry - size and wear - and diet between rocky shore and heterogeneous sand flat habitats. We predicted that, intra-specifically, crabs from rocky shores would consume more hard-shelled prey owing to their high availability and consequently, would display chelipeds with the following claw characteristics: a higher degree of claw damage, stronger musculature (higher propel height) and increased mechanical advantage (defined as the ratio of input lever length to output lever length) than crabs in the heterogeneous sand flat habitats. Sampling was performed in heterogeneous sand flat habitats and rocky shores of the Central Portuguese coast. For each crab species, carapace width, diet composition and several claw morphometric measures were recorded, revealing significant intra-specific differences (using multivariate analysis) between shore types. We found that E. verrucosa and P. marmoratus consumed more hard prey on rocky shore than on sand flat habitats, which resulted in rocky shore crabs having more accentuated dentition wear and larger musculature than their sand flat habitat counterparts. We suggest that the strong response of crab claw morphometry to environmentally induced diet variations is an important mechanism in the successful adaptation of crab species to inhabit differing habitats. A major implication is that the impact of the same species on prey may vary largely with habitat type as a result of predation efficiency varying with claw condition. [ABSTRACT FROM AUTHOR]

In habitats where competition for space is a shaping force of animal distribution such as in the intertidal rocky ecosystem, new habitats are readily taken by colonising species. We examined the importance of empty Chthamalus spp. tests as a habitat for the intertidal common periwinkle Melaraphe neritoides on Portuguese rocky shores. The role played by the space between neighbouring barnacles as a habitat for other species has been largely studied with regard to how an ecosystem functions, whereas the equivalent role of empty barnacle tests remains largely unknown. The small periwinkle is one of the most abundant snails in European rocky shores and is an important prey for key mobile predators. Biological facilitation is common in the rocky intertidal zone, where biological structures often potentiate the abundance of other species. The role played by barnacles as biological facilitators through habitat provision is not fully understood. In this study, the abundance and morphometric features of empty barnacle tests and their occupants were examined across shore levels and shores with differing exposures, as these are important gradients explaining barnacle distribution. The availability of empty barnacle tests was also experimentally manipulated to examine the percentage, time and length of occupation. Empty barnacles were more abundant on the midshore of sheltered shores and barnacle tests were wider on the upper shore but taller on the midshore. The minimum barnacle test occupation rate by the periwinkle was 70%. Barnacle shell height was an important factor determining snail occupation, where taller barnacles harboured significantly more, but not necessarily larger, snails. Snails outside the barnacle tests were significantly larger than those found within, suggesting that this crustacean group has an increased importance as a habitat for juvenile snails, thus potentially influencing the population dynamics of M. neritoides. We found that occupation of experimentally created empty barnacles was extremely high (70%) on the day after, and remained at 100% after 3 months of monitoring. Our study is the first of its kind to focus on the features of barnacle tests that snails occupy and their occupying snail traits. According to our results, it is clear that barnacles have an important role in providing additional habitat for young gastropods. The small periwinkle is an important grazer and prey for intertidal and subtidal foraging predators; hence, the potential refuge role of barnacle tests for juvenile M. neritoides may be important in the dynamics of intertidal communities. [ABSTRACT FROM AUTHOR]

Friction stir welding is an emergent technique that still lacks optimization studies in the literature. Optimum parameters are of prime importance for future investigations, as it will allow for consistent and sound welds. This is of even greater relevance for industrial applications, as for friction stir welding to become a mainstream joining technology. This paper presents an optimization study of friction stir welded butt joints through the Taguchi method. The most influent welding parameters and their trends were identified. The process optimization for the selected aluminium alloy was achieved and the best parameters combination to accomplished quality welds was selected. The parameters combination that lead to higher mechanical stiffness were: 1000 min-1, 290 mm/min, 0.15 mm from the probe to the root surface and a shoulder/probe diameters ratio of 2 (shoulder diameter of 12 mm). Equations to estimate joint properties were derived by multiregression. [ABSTRACT FROM AUTHOR]

Background Sclerotinia sclerotiorum is a necrotrophic fungus that is pathogenic to many plants. Genomic analysis of its revealed transposable element expansion that has strongly influenced the evolutionary trajectory of several species. Transposons from the Tc1-Mariner superfamily are thought to be ubiquitous components of fungal genomes and are generally found in low copy numbers with large numbers of deleterious mutations in their transposase coding sequence. Results This study shows that the genome of S. sclerotiorum has a large number of copies of Tc1- Mariner transposons, and in silico analysis shows evidence that they were recently active. This finding was confirmed by expressed sequence tag (EST) analysis. Fourteen new Tc1- Mariner transposon families that were distributed throughout the genome were identified, and in some cases, due to the excision/retention of introns, different transcripts were observed for the same family, which might be the result of an efficient strategy to circumvent mutations that generate premature stop codons in the RNA sequence. In addition, the presence of these introns shows that the transposase protein has a flexible coding sequence and, consequently, conformation. No evidence for RIP-like gene silencing mechanisms, which are commonly found in fungi, was found in the identified Tc1-Mariner elements, and analysis of the genomic insertion sites of these elements showed that they were widely distributed throughout the genome with some copies located near the 3' regions of genes. In particular, EST analysis demonstrated that one of these copies was co-expressed with a gene, which showed the potential for these elements to undergo exaptation. Conclusions Fourteen novel Tc1-Mariner families were characterized. Some families had evidence of introns, which might or might not be excised depending on the family or element in question, and this finding demonstrates a possible strategy for overcoming possible mutations that generate premature stop codons in a RNA sequence. Tc1-Mariner elements likely play an important role in the structure and evolution of the S. sclerotiorum genome. [ABSTRACT FROM AUTHOR]

Background Cochliobolus heterostrophus is a dothideomycete that causes Southern Corn Leaf Blight disease. There are two races, race O and race T that differ by the absence (race O) and presence (race T) of ∼ 1.2-Mb of DNA encoding genes responsible for the production of Ttoxin, which makes race T much more virulent than race O. The presence of repetitive elements in fungal genomes is considered to be an important source of genetic variability between different species. Results A detailed analysis of class I and II TEs identified in the near complete genome sequence of race O was performed. In total in race O, 12 new families of transposons were identified. In silico evidence of recent activity was found for many of the transposons and analyses of expressed sequence tags (ESTs) demonstrated that these elements were actively transcribed. Various potentially active TEs were found near coding regions and may modify the expression and structure of these genes by acting as ectopic recombination sites. Transposons were found on scaffolds carrying polyketide synthase encoding genes, responsible for production of T-toxin in race T. Strong evidence of ectopic recombination was found, demonstrating that TEs can play an important role in the modulation of genome architecture of this species. The Repeat Induced Point mutation (RIP) silencing mechanism was shown to have high specificity in C. heterostrophus, acting only on transposons near coding regions. Conclusions New families of transposons were identified. In C. heterostrophus, the RIP silencing mechanism is efficient and selective. The co-localization of effector genes and TEs, therefore, exposes those genes to high rates of point mutations. This may accelerate the rate of evolution of these genes, providing a potential advantage for the host. Additionally, it was shown that ectopic recombination promoted by TEs appears to be the major event in the genome reorganization of this species and that a large number of elements are still potentially active. So, this study provides information about the potential impact of TEs on the evolution of C. heterostrophus. [ABSTRACT FROM AUTHOR]

Viruses are extremely diverse and abundant and are present in countless environments. Giant viruses of the Megavirales order have emerged as a fascinating research topic for virologists around the world. As evidence of their ubiquity and ecological impact, mimiviruses have been found in multiple environmental samples. However, isolation of these viruses from environmental samples is inefficient, mainly due to methodological limitations and lack of information regarding the interactions between viruses and substrates. In this work, we demonstrate the long-lasting stability of mimivirus in environmental (freshwater and saline water) and hospital (ventilator plastic device tube) substrates, showing the detection of infectious particles after more than 9 months. In addition, an enrichment protocol was implemented that remarkably increased mimivirus detection from all tested substrates, including field tests. Moreover, biological, morphological and genetic tests revealed that the enrichment protocol maintained mimivirus particle integrity. In conclusion, our work demonstrated the stability of APMV in samples of environmental and health interest and proposed a reliable and easy protocol to improve giant virus isolation. The data presented here can guide future giant virus detection and isolation studies. [ABSTRACT FROM AUTHOR]

Obesity prevalence in the Brazilian adult population is 12.5% among men and 16.9% among women. Obesity control has been a subject of concern in Brazilian health policies since the publication of the National Food and Nutrition Policy in 1999. The initiatives include a comprehensive national intersectorial plan for obesity prevention and control focused on confronting its social and environmental causes, development of a food and nutrition education framework aimed at intersectorial public policies in the food and nutritional security field, promotion and provision of healthy food in school environments (linked to family farming), structuring nutrition actions in primary healthcare in the national healthcare system, promoting community physical activity, food regulation and control, and encouragement of public participation and food control. We conclude that several initiatives have been developed in Brazil to deal with the challenge of implementing an intergovernmental, intersectorial response to reverse the rising overweight and obesity rates. The success of this response will depend on a governance model that promotes joint and integrated action by different sectors and active participation of society to consolidate the actions, places and laws that protect health and promote healthy lifestyles. [ABSTRACT FROM AUTHOR]

Background: Mycosphaerella fijiensis is a ascomycete that causes Black Sigatoka in bananas. Recently, the M. fijiensis genome was sequenced. Repetitive sequences are ubiquitous components of fungal genomes. In most genomic analyses, repetitive sequences are associated with transposable elements (TEs). TEs are dispersed repetitive DNA sequences found in a host genome. These elements have the ability to move from one location to another within the genome, and their insertion can cause a wide spectrum of mutations in their hosts. Some of the deleterious effects of TEs may be due to ectopic recombination among TEs of the same family. In addition, some transposons are physically linked to genes and can control their expression. To prevent possible damage caused by the presence of TEs in the genome, some fungi possess TE-silencing mechanisms, such as RIP (Repeat Induced Point mutation). In this study, the abundance, distribution and potential impact of TEs in the genome of M. fijiensis were investigated. Results: A total of 613 LTR-Gypsy and 27 LTR-Copia complete elements of the class I were detected. Among the class II elements, a total of 28 Mariner, five Mutator and one Harbinger complete elements were identified. The results of this study indicate that transposons were and are important ectopic recombination sites. A distribution analysis of a transposable element from each class of the M. fijiensis isolates revealed variable hybridization profiles, indicating the activity of these elements. Several genes encoding proteins involved in important metabolic pathways and with potential correlation to pathogenicity systems were identified upstream and downstream of transposable elements. A comparison of the sequences from different transposon groups suggested the action of the RIP silencing mechanism in the genome of this microorganism. Conclusions: The analysis of TEs in M. fijiensis suggests that TEs play an important role in the evolution of this organism because the activity of these elements, as well as the rearrangements caused by ectopic recombination, can result in deletion, duplication, inversion and translocation. Some of these changes can potentially modify gene structure or expression and, thus, facilitate the emergence of new strains of this pathogen. [ABSTRACT FROM AUTHOR]

This study was performed to evaluate the effects of different in vitro ageing techniques on the dentine-bonded interface produced by a two-step etch-and-rinse adhesive. Composite build-ups were bonded to sectioned human molars using XP BOND and cut into non-trimmed dentine–composite beams for microtensile testing. Beams were assigned to one of the following storage conditions: (i) artificial saliva, 24 h (control); (ii) 10% sodium hypochlorite (NaOCl), 1 h; (iii) 10% NaOCl, 3 h; (iv) 60,000 thermal cycles, 2 months; (v) artificial saliva, 2 months; (vi) 60,000 thermal cycles, 6 months; and (vii) artificial saliva, 6 months. Beams were then pulled until failure and bond strength was calculated. Additional specimens were examined to investigate interfacial nanoleakage expression. NaOCl solution significantly reduced bonding compared with the control (group 2 = group 3 < group 1); and thermocycling reduced the bond strength in comparison to specimens stored for the same time-period in artificial saliva (group 4 < group 5; group 6 < group 7). Artificial ageing affected bond strength only after 6 months of storage (group 7 < group 5 = group 1). Increased nanoleakage was found under all ageing conditions in comparison with controls. NaOCl solution is a rapid and reliable in vitro ageing method for examining the durability of the adhesive interface produced by two-step etch-and-rinse adhesive systems. [ABSTRACT FROM AUTHOR]

Ecological environments research helps to assess the impacts on forests and managing forests. The usage of novel software and hardware technologies enforces the solution of tasks related to this problem. In addition, the lack of connectivity for large data throughput raises the demand for edge-computing-based solutions towards this goal. Therefore, in this work, we evaluate the opportunity of using a Wearable edge AI concept in a forest environment. For this matter, we propose a new approach to the hardware/software co-design process. We also address the possibility of creating wearable edge AI, where the wireless personal and body area networks are platforms for building applications using edge AI. Finally, we evaluate a case study to test the possibility of performing an edge AI task in a wearable-based environment. Thus, in this work, we evaluate the system to achieve the desired task, the hardware resource and performance, and the network latency associated with each part of the process. Through this work, we validated both the design pattern review and case study. In the case study, the developed algorithms could classify diseased leaves with a circa 90% accuracy with the proposed technique in the field. This results can be reviewed in the laboratory with more modern models that reached up to 96% global accuracy. The system could also perform the desired tasks with a quality factor of 0.95, considering the usage of three devices. Finally, it detected a disease epicenter with an offset of circa 0.5 m in a 6 m × 6 m × 12 m space. These results enforce the usage of the proposed methods in the targeted environment and the proposed changes in the co-design pattern. [ABSTRACT FROM AUTHOR]

B[e] supergiants (sgB[e]) are rare objects whose evolutionary stage remains uncertain. Observationally, they display strong Balmer emission lines, infrared excess, and intrinsic polarization, indicating a non-spherical circumstellar envelope. We present a study of the sgB[e] RMC 82, using new spectropolarimetric data complemented by photometry from the ultraviolet (UV) to the mid-infrared. Our two-component model comprises a slow, dense equatorial wind wherein dust grains form and a fast polar wind. We applied the hdust radiative transfer code and Bayesian statistics to infer the parameters from a grid of 3240 pre-computed models. The model accurately reproduces the spectral energy distribution and polarized spectrum, but struggles to match the H α emission. Our results suggest a large mass-loss rate of |$6.6 \times 10^{-6}\, \mathrm{{\rm M}_{\odot }\, yr^{-1}\, sr^{-1}}$|⁠. The dense wind is confined within an opening angle of 11°. The hottest dust grains are located at 277  R * with a temperature of 870 K. The dust grains are porous, with a density of 0.051  |$\rm {g\, cm^{-3}}$|⁠. The central star was found to be significantly hotter than previous estimates (T eff =  |$27\, 000$|  K). By comparing models with different components, we find that gas reprocesses a significant amount of UV radiation, shielding the dust. However, the dust also scatters UV photons back to the inner disc, increasing its temperature and H α emission. We conclude that self-consistent models, that account for the gas–dust interplay in the envelope, are essential for studying sgB[e] and similar objects. [ABSTRACT FROM AUTHOR]

The influence of the impurity background on the recombination processes in type-II InAs/GaSb superlattice photodiodes with a cutoff wavelength of approximately 4.8 μm was investigated by electroluminescence measurements. Using an iterative fitting procedure based on the dependence of the quantum efficiency of the electroluminescence on the injection current, the Auger and Shockley-Read-Hall lifetimes were determined for photodiodes with background concentration below 1015 cm-3. The authors determined in which range of the injection current Shockley-Read-Hall or Auger recombination is predominant. At T=300 K, the findings indicate that in high quality material with a low background concentration Auger effect becomes the prevalent mechanism even at low applied current. [ABSTRACT FROM AUTHOR]

Non-relativistic quantum effects of the topology of the spacetime with the distortion of a vertical line into a vertical spiral on the harmonic oscillator are investigated. By searching for analytical solutions to the Schrödinger equation in this topological defect background, it is shown that the topology of the spacetime modifies the spectrum of energy of the harmonic oscillator. Besides, it is shown that there exists an Aharonov–Bohm-type effect for bound states. [ABSTRACT FROM AUTHOR]

It is analysed Aharonov–Bohm-type effects when a spinless quantum particle is in an elastic medium with the distortion of a vertical line into a vertical spiral. By confining the spinless particle to a cylindrical box, the analogue of the Aharonov–Bohm effect for bound states is observed due to the influence of the topological defect on the allowed energies of the system. It corresponds to the shift in the angular momentum quantum number yielded by the effects of the topology of the distortion of a vertical line into a vertical spiral. In addition, it is analysed the effects of rotation. It is shown that the Aharonov–Bohm effect for bound states exists. Besides, there is an analogue of the coupling between the angular momentum and angular velocity of the rotating frame. [ABSTRACT FROM AUTHOR]

Classical B emission (Be) stars are fast rotating, near-main-sequence B-type stars. The rotation and the presence of circumstellar discs profoundly modify the observables of active Be stars. Our goal is to infer stellar and disc parameters, as well as distance and interstellar extinction, using the currently most favoured physical models for these objects. We present BeAtlas , a grid of |$61\, 600$| non-local thermodynamic equilibrium radiative transfer models for Be stars, calculated with the hdust code. The grid was coupled with a Monte Carlo Markov chain (MCMC) code to sample the posterior distribution. We test our method on two well-studied Be stars, α Eri and β CMi, using photometric, polarimetric, and spectroscopic data as input to the code. We recover literature determinations for most of the parameters of the targets, in particular the mass and age of α Eri, the disc parameters of β CMi, and their distances and inclinations. The main discrepancy is that we estimate lower rotational rates than previous works. We confirm previously detected signs of disc truncation in β CMi and note that its inner disc seems to have a flatter density slope than its outer disc. The correlations between the parameters are complex, further indicating that exploring the entire parameter space simultaneously is a more robust approach, statistically. The combination of BeAtlas and Bayesian-MCMC techniques proves successful, and a powerful new tool for the field: The fundamental parameters of any Be star can now be estimated in a matter of hours or days. [ABSTRACT FROM AUTHOR]

Bos taurus indicusfemales provide a greater in vivooocyte recovery (2-4 times more) in comparision with Bos taurus taurus. This aspect has strongly contributed for the success of the embryo industry in Brazil. Little information is available to explain this difference. Our objective was to test the hypothesis that the difference in oocyte yield is a result of higher numbers of preantral follicles in the ovaries of B. indicusfemales. Ovaries (n= 44) of fetuses aging from 180 to 240 days and of heifers from 20 and 24 months were collected from Bos taurus indicus(Nelore) and Bos taurus taurus(Aberdeen Angus) females at a slaughterhouse. Fetal age was estimated from the crown-rump length (Evans HE and Sack WO 1973 Anat. Hist. Embryol. 2, 11-45). Ovaries from Nelore fetuses (n= 10) and heifers (n= 12) and Aberdeen Angus fetuses (n= 10) and heifers (n= 12) were cut longitudinally into two halves, fixed in Bouin''s solution, and processed for histological evaluation. The ovarian halves were dehydrated in alcohol, cleared with xylene, embbebed in paraffin, and serially sectioned at 7 μm. Every 120th section was mounted and stained with periodic acid Schiff and hematoxylin. The number of preantral follicles was estimated through the counting of follicles in each section using the nucleus of the oocyte as a marker and a correction factor (Gougeon A and Chainy GBN 1987 J. Reprod. Fertil. 81, 433-442). Only 1 ovary per female was analyzed. Preantral follicles were classified according to the developmental stage as primordial (1 layer of flattened granulosa cells surrounding the oocyte), primary (1 layer of cuboidal granulosa cells), or secondary (2 or more layers of cuboidal granulosa cells), and as normal or degenerated according to their morphological appearance. The number of preantral follicles was not normally distributed and was compared using the Mann-Whitney test. There was no difference (P> 0.05) between the average number of preantral follicles in the ovaries of Bos indicusand Bos taurusfemales. The average number of preantral follicles per female was 143 929 ± 253 (mean ± SD) and 285 155 ± 570 for Bos taurusand Bos indicusfetuses, respectively, and 76 851 ± 280 and 109 673 ± 293 for Bos taurus andBos indicus heifers (P> 0.05), respectively. A large variation in numbers of preantral follicles was observed among individuals within the same category and between breeds. Our results suggest that there might be differences in mechanisms controlling follicle development after the preantral stage accounting for the greater oocyte yield from Bos indicusfemales. This work was supported by grants from the Universidad Nacional del Litoral (CAI+D program), Universidad Nacional de Lomas de Zamora, the Argentine National Agency for the Promotion of Science and Technology (ANPCyT), and the Argentine National Council for Science and Technology (CONICET). [ABSTRACT FROM AUTHOR]

Water pollution by dyes has been a major environmental problem to be tackled, and magnetic adsorbents appear as promising alternatives to solve it. Herein, magnetic activated carbons were prepared by the single−step method from Sapelli wood sawdust, properly characterized, and applied as adsorbents for brilliant blue dye removal. In particular, two magnetic activated carbons, MAC1105 and MAC111, were prepared using the proportion of biomass KOH of 1:1 and varying the proportion of NiCl2 of 0.5 and 1. The characterization results demonstrated that the different proportions of NiCl2 mainly influenced the textural characteristics of the adsorbents. An increase in the surface area from 260.0 to 331.5 m2 g−1 and in the total pore volume from 0.075 to 0.095 cm3 g−1 was observed with the weight ratio of NiCl2. Both adsorbents exhibit ferromagnetic properties and the presence of nanostructured Ni particles. The different properties of the materials influenced the adsorption kinetics and equilibrium of brilliant blue dye. MAC111 showed faster kinetics, reaching the equilibrium in around 10 min, while for MAC1105, it took 60 min for the equilibrium to be reached. In addition, based on the Sips isotherm, the maximum adsorption capacity was 98.12 mg g−1 for MAC111, while for MAC1105, it was 60.73 mg g−1. Furthermore, MAC111 presented the potential to be reused in more adsorption cycles than MAC1105, and the use of the adsorbents in the treatment of a simulated effluent exhibited high effectiveness, with removal efficiencies of up to 90%. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Streptococcus pneumoniae colonizes the nasopharynx of healthy individuals establishing a commensal relationship with the host. In some conditions, bacteria invade the lower respiratory tract and innate immune responses are crucial to avoid diseases such as pneumonia, sepsis, or meningitis. Methods: Here, we compared the susceptibility to pneumococcal respiratory infection of two outbred mouse lines, AIRmin and AIRmax, selected for low or high acute inflammatory responses, respectively. Results: AIRmin mice showed increased susceptibility to infection with different pneumococcal serotypes, when compared to AIRmax. Significant higher numbers of alveolar macrophages expressing the CD206 mannose receptor were observed in AIRmin mice when compared to AIRmax mice. Despite this difference, secretion of several cytokines and chemokines in the respiratory tract of AIRmin and AIRmax mice, after infection, was similar. The only exception was CXCL5, which was highly induced after pneumococcal infection in AIRmax mice but not in AIRmin mice. Reduced expression of the matrix metalloproteinases (MMP) 2, 3, 8, and 9, as well as reduced activities of MMPs were also observed in the lungs of AIRmin mice, after infection. Such impaired responses may have contributed to the low influx of neutrophils observed in the airways of these mice. Finally, high percentages of macrophages and neutrophils in apoptosis or necrosis, at the site of infection, were also observed in AIRmin mice, suggesting that leukocyte functionality is also compromised. Conclusions: Our results indicate that CXCL5 and MMPs contribute to the resistance to pneumococcal infection in mice. [ABSTRACT FROM AUTHOR]

Context Nutritional interventions for newborns with brain injury are scarce, and there are gaps in the knowledge of their mechanisms of action in preventing the occurrence of cerebral palsy (CP) or the incidence of other developmental disabilities. Objective The objective of this review was to assess the effect of nutritional interventions in preventing nonprogressive congenital or perinatal brain injuries, or in improving outcomes related to neurological development. Data Sources Randomized trials on any nutritional intervention for pregnant women at risk of preterm delivery, or for children with low birth weight, preterm, or with confirmed or suspected microcephaly, CP, or fetal alcohol syndrome disorders (FASDs) were retrieved from MEDLINE, Embase, Scopus, Web of Science, LILACS, and CENTRAL databases from inception to September 17, 2020. Data Extraction Data extraction, risk of bias (Cochrane Risk of Bias tool 2), and quality of evidence (GRADE approach) were assessed by 2 authors. Data Analysis Pooled risk ratios (RRs) with 95% confidence intervals were calculated using a random-effects meta-analysis. Seventeen studies were included on intravenous interventions (magnesium sulfate [n = 5], amino acids [n = 4], vitamin A [n = 1], and N-acetylcysteine [n = 1]); enteral interventions (vitamin D [n = 1], prebiotic [n = 1], nutrient-enriched formula [n = 1], and speed of increasing milk feeds [n = 1]); and oral interventions (choline [n = 1] and docosahexaenoic acid, choline, and uridine monophosphate [n = 1]). All studies assessed CP, except 1 on FASDs. Eight studies were judged as having high risk of bias. Five studies (7413 babies) with high-quality evidence demonstrated decreased risk of childhood CP (RR = 0.68, 95% CI: 0.52–0.88) with magnesium sulfate. Interventions with amino acids had no effect on CP prevention or other outcomes. Except for 1 study, no other intervention decreased the risk of CP or FASDs. Conclusion Although different types of nutritional interventions were found, only those with antenatal magnesium sulfate were effective in decreasing CP risk in preterm infants. Well-designed, adequately powered randomized clinical trials are required. [ABSTRACT FROM AUTHOR]

Plants are constantly exposed to environmental changes that affect their performance. Metabolic adjustments are crucial to controlling energy homoeostasis and plant survival, particularly during stress. Under carbon starvation, coordinated reprogramming is initiated to adjust metabolic processes, which culminate in premature senescence. Notwithstanding, the regulatory networks that modulate transcriptional control during low energy remain poorly understood. Here, we show that the WRKY45 transcription factor is highly induced during both developmental and dark‐induced senescence. The overexpression of Arabidopsis WRKY45 resulted in an early senescence phenotype characterized by a reduction of maximum photochemical efficiency of photosystem II and chlorophyll levels in the later stages of darkness. The detailed metabolic characterization showed significant changes in amino acids coupled with the accumulation of organic acids in WRKY45 overexpression lines during dark‐induced senescence. Furthermore, the markedly upregulation of alternative oxidase (AOX1a, AOX1d) and electron transfer flavoprotein/ubiquinone oxidoreductase (ETFQO) genes suggested that WRKY45 is associated with a dysregulation of mitochondrial signalling and the activation of alternative respiration rather than amino acids catabolism regulation. Collectively our results provided evidence that WRKY45 is involved in the plant metabolic reprogramming following carbon starvation and highlight the potential role of WRKY45 in the modulation of mitochondrial signalling pathways. The WRKY45 transcription factor mediates metabolic reprogramming during carbon starvation. The overexpression of WRKY45 triggered a differential accumulation of amino acids, organic acids and respiratory adjustments through the regulation of mitochondrial signalling and alternative respiration. [ABSTRACT FROM AUTHOR]

We present effective-mass calculations of the bound-state energy levels of electrons confined inside lens-shaped InxGa1−xAs quantum dots (QDs) embedded in a GaAs matrix, taking into account the strain as well as the In gradient inside the QDs due to the strong In segregation and In-Ga intermixing present in the InxGa1−xAs/GaAs system. In order to perform the calculations, we used a continuum model for the strain, and the QDs and wetting layer were divided into their constituting monolayers, each one with a different In concentration, to be able to produce a specific composition profile. Our results clearly show that the introduction of such effects is very important if one desires to correctly reproduce or predict the optoelectronic properties of these nanostructures. [ABSTRACT FROM AUTHOR]

In recent years, Brazil has become the leading country in the world for the number of embryos produced in vitro(Thibier M 2009 IETS Embryo Transfer Newsletter 22, 12-19). This is partly due to the large numbers of Bos indicusanimals in Brazil, making up about 80% of the total cattle. The mean oocyte production per ultrasound-guided follicular aspiration from Bos indicusis higher than those for European breeds (Pontes JHF et al.2009 Theriogenology 71, 690-697). In the present study, we analyzed 5407 ovum pick ups (OPU) and compared the average production of total (n= 90,086) and viable (n= 64,826) oocytes and the number of embryos produced in vitrofrom Gir (Bos taurus indicus), Holstein (Bos taurus taurus), 1/4 Holstein × 3/4 Gir, and 1/2 Holstein-Gir crossbreed cows. To obtain oocytes, OPU was repeated from 4 to 7 times (mean = 5.7 ± 2.4) in each donor cow aged from 3 to 7 years (mean = 5.0 ± 2.3) during a 12-mo period. COCs (n= 90,086) obtained were classified according to the presence of cumulus cells and the oocyte cytoplasm aspect (homogeneous or heterogeneous/fragmented). The viable oocytes (n= 64,826) were in vitromatured for 24 h at 38.8°C in an atmosphere of 5% CO2in air. Since this was a commercial programm, frozen sexed semen (2 × 106mL-1) from Gir (n= 8) or Holstein (n= 7) sires previously tested for high efficiency was used for IVF. Fertilization was carried out (18-20 h) and the presumed embryos were cultured for 7 days in the same conditions as were used for IVM. Data were analyzed by ANOVA. On average, 16.7 ± 6.2 oocytes were obtained per OPU/IVF procedure and 71.96% were considered viable. The mean numbers of total oocytes per OPU/IVF procedure were 17.1 ± 4.4 for Gir cows (n= 617), 11.4 ± 3.9 for Holstein cows (n= 180), 20.4 ± 5.8 for 1/4 Holstein × 3/4 Gir (n= 44), and 31.4 ± 5.6 for 1/2 Holstein-Gir crossbreed females (n= 37, P< 0.01). The mean numbers of viable oocytes per OPU/IVF procedure were 12.1 ± 3.8 for Gir cows, 8.0 ± 2.6 for Holstein cows, 16.8, ± 5.0 for 1/4 Holstein × 3/4 Gir, and 24.3 ± 4.7 for 1/2 Holstein-Gir crossbreed females (P< 0.01). The average number of embryos produced by OPU/IVF were 3.2 (n= 12,243/3378) for Gir cows, 2.2 (n= 2426/1138) for Holstein cows, 3.9 (n= 1033/267) for 1/4 Holstein × 3/4 Gir, and 5.5 (n= 1222/224) for 1/2 Holstein-Gir. The average number of embryos produced per IVF session from 1/2 taurus × indicusdonor cows was greater (P< 0.01) than from Bos indicuscows. The number of recoverable and viable oocytes and the number of embryos produced in vitrofrom Bos indicusdonors were higher than from Bos taurusfemales. Therefore, the highest oocyte yield and the greatest embryo production were obtained from 1/2 taurus × indicusfemales. This work was supported by In Vitro Brasil. [ABSTRACT FROM AUTHOR]

In 2003, Acanthamoeba polyphaga mimivirus (APMV) was first described and began to impact researchers around the world, due to its structural and genetic complexity. This virus founded the family Mimiviridae. In recent years, several new giant viruses have been isolated from different environments and specimens. Giant virus research is in its initial phase and information that may arise in the coming years may change current conceptions of life, diversity and evolution. Thus, this review aims to condense the studies conducted so far about the features and peculiarities of APMV, from its discovery to its clinical relevance. [ABSTRACT FROM AUTHOR]

Spinocerebellar ataxias (SCAs) are characterized by a heterogeneous set of clinical manifestations. Our aims were to assess the neurological features of SCA3, and to describe and test the feasibility, reliability, and validity of a comprehensive Neurological Examination Score for Spinocerebellar Ataxia (NESSCA). The NESSCA was administered to molecularly diagnosed SCA3 patients at an outpatient neurogenetics clinic. The scale, based on the standardized neurological examination, consisted of 18 items that yielded a total score ranging from 0 to 40. The score’s interrater reliability and internal consistency were investigated, and a principal components analysis and a correlation with external measures were performed. Ninety-nine individuals were evaluated. Interrater reliability ranged from 0.8 to 1 across individual items ( P < 0.001); internal consistency, indicated by Cronbach’s alpha, was 0.77. NESSCA scores were significantly correlated with measures of disease severity: disease stage (rho = 0.76, P < 0.001), duration (rho = 0.56, P < 0.001), and length of CAG repeat (rho = 0.30, P < 0.05). NESSCA was a reliable measure for the assessment of distinct neurological deficits in SCA3 patients. Global scores correlated with all external variables tested, showing NESSCA to be a comprehensive measure of disease severity that is both clinically useful and scientifically valid. [ABSTRACT FROM AUTHOR]

Photoluminescence measurements at different temperatures have been performed to investigate the optical response of a two-dimensional electron gas in n-type wide parabolic quantum wells. A series of samples with different well widths in the range of 1000–3000 Å was analyzed. Many-body effects, usually observed in the recombination process of a two-dimensional electron gas, appear as a strong enhancement in the photoluminescence spectra at the Fermi level at low temperature only in the thinnest parabolic quantum wells. The suppression of the many-body effect in the thicker quantum wells was attributed to the decrease of the overlap between the wavefunctions of the photocreated holes and the two-dimensional electrons belonging to the highest occupied electron subband. [ABSTRACT FROM AUTHOR]

The optical properties of n- and p-type, modulation- and delta-doped Al[sub 0.35]Ga[sub 0.65]As-GaAs single heterojunctions (SHs) have been studied by means of low-temperature photoluminescence measurement and self-consistent calculation. A very strong, broad, and asymmetric H-band emission was observed only in p-type delta-doped SH. When the optical excitation intensity increases by two orders of magnitude a redshift as large as 27 meV is observed in the H-band emission energy. The large redshift observed is attributed to both inefficiency of screening in the two-dimensional-hole gas and effective band-gap renormalization. It was also observed that the H-band emission strongly depends upon the doping type (n or p type) and doping profile (modulation doping or delta doping). [ABSTRACT FROM AUTHOR]

The surface segregation of indium (In) atoms was investigated during the growth of InGaAs layers by reflection high-energy electron diffraction (RHEED). We observed that the decay constant of the RHEED-oscillation amplitude during growth depends on the growth conditions and is related, in a very simple way, to the segregation coefficient of the In atoms in the InGaAs layers. [ABSTRACT FROM AUTHOR]

Summary: Gobius paganellus, Lipophrys pholis and Coryphoblennius galerita are wide‐spread intertidal fish that spend their earlier life stages in rock pools, and yet very little is known about their site fidelity behaviour. For these species, fidelity to rockpools may result in increased fitness costs in a predicted scenario of warmer sea water, due to the low thermal inertia of these water bodies. In this context, it is relevant to investigate these species' site fidelity. We made a mark‐recapture study to assess the mentioned species' movements within and between rockpools. We tagged a total of 530 individuals of the aforementioned species with the Visible Implant Elastomer and tracked their movement for a 7‐month period. We found that site fidelity and specific rockpools conditions are important factors in distribution of intertidal blennies and gobies. We also examined the relations between rockpool volume, depth and site fidelity. We found that G. paganellus tends to remain in its original marking pool, with an average recapture rate of 20.5%, but showed no evidence of inter‐pool movement. Rockpool depth, however, proved to be important in the blennies' movements. Our findings are among the first to prove that a mark‐recapture method can be successfully used to track intertidal fish movements. In particular, we showed that G. paganellus presents site fidelity in intertidal rockpools during its early ontogeny for a period of two to three months. [ABSTRACT FROM AUTHOR]

Calculations using the dynamical theory of diffraction together with a sample model which considers the segregation of indium atoms were employed to fit the high-resolution x-ray spectra of strained InGaAs/GaAs quantum wells grown by molecular-beam epitaxy. The segregation coefficients obtained from the best fits to the experimental data of samples grown at different temperatures are in excellent agreement with the expected values and confirm that x-ray diffraction is a valuable tool for the investigation of the segregation phenomenon. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

•A number of genes that confer resistance to coffee leaf rust (SH1-SH9) have been identified within the genus Coffea, but despite many years of research on this pathosystem, the complementary avirulence genes of Hemileia vastatrix have not been reported. • After identification of H. vastatrix effector candidate genes (HvECs) expressed at different stages of its lifecycle, we established an assay to characterize HvEC proteins by delivering them into coffee cells via the type-three secretion system (T3SS) of Pseudomonas syringae pv. garcae (Psgc). • Employing a calmodulin-dependent adenylate cyclase assay, we demonstrate that Psgc recognizes a heterologous P. syringae T3SS secretion signal which enables us to translocate HvECs into the cytoplasm of coffee cells. Using this Psgc-adapted effector detector vector (EDV) system, we found that HvEC-016 suppresses the growth of Psgc on coffee genotypes with the SH1 resistance gene. Suppression of bacterial blight symptoms in SH1 plants was associated with reduced bacterial multiplication. By contrast, HvEC-016 enhanced bacterial multiplication in SH1-lacking plants. • Our findings suggest that HvEC-016 may be recognized by the plant immune system in a SH1-dependent manner. Thus, our experimental approach is an effective tool for the characterization of effector/avirulence proteins of this important pathogen. [ABSTRACT FROM AUTHOR]

Chitons are very common molluscs on European rocky shores. They are common prey of fish and crabs and often display several colour morphs within a given habitat. Predation is one of the potential mechanisms accounting for chiton colour polymorphism. The colour variation is considered to provide a camouflage protection through a match with the substratum surface typology. However, the effectiveness of chiton polymorphism as a predation defence requires further investigation. Previously we found a relationship between chiton colour morphs and substrate characteristics, with chitons most commonly found on substrates that were of similar colour to their shells. Here, we examined whether each morph displayed an active choice for matching the substratum. Next, we assessed if the predation success of the intertidal common crab Carcinus maenas varied significantly with the absence/presence of an apparent camouflage effect created between the chiton colour morph and the substratum type. The present study indicates that chiton colour morphs probably actively choose substratum types where they blend in. Carcinus maenas was able to prey on all Lepidochitona cinereus colour morphs, regardless of the substrate camouflage effect. Surprisingly, the predation frequency was higher on camouflaged chitons than on contrasting chitons. It was concluded that chiton camouflage is probably not a defence mechanism against predation by the crab C. maenas, and that chiton colour polymorphism is probably promoted by other, more visual predators. [ABSTRACT FROM AUTHOR]

This study presents a new approach to examining European chiton habitat use according to morphological characteristics. Time-search transects were conducted on four Portuguese rocky shores at two shore levels. The chiton species, abundance and individual morphometric features were recorded and related to the substratum dominant epiphytes and surface roughness. The chiton Lepidochitona cinerea (Linnaeus 1767) was the dominant species (77%), followed by Leptochiton algesirensis (Capellini 1859) (15%) and Acanthochitona crinita (Pennant 1777) (8%). Species abundance did not vary significantly with shore level or amongst shores. Six colour morphs were considered for Lepidochitona cinerea, four for A. crinita and one for Lepidochiton algesirensis. Substratum characteristics significantly explained the variation in species and colour morph distribution. There was a high correlation between the presence/absence and type of epiphytic algae and the substratum surface roughness level. We hypothesize that three mechanisms operating either independently or in interaction may explain the non-random distribution of colour polymorphisms according to their habitat characteristics: (i) presence of algae that are part of their diet; (ii) use of rock as shelter - for instance, crevices and cover resulting from algae fronds and; (iii) morph-rock colour matching as a camouflage mechanism to reduce predation pressure. [ABSTRACT FROM AUTHOR]

Background: The identification of novel giant viruses from the nucleocytoplasmic large DNA viruses group and their virophages has increased in the last decade and has helped to shed light on viral evolution. This study describe the discovery, isolation and characterization of Samba virus (SMBV), a novel giant virus belonging to the Mimivirus genus, which was isolated from the Negro River in the Brazilian Amazon. We also report the isolation of an SMBV-associated virophage named Rio Negro (RNV), which is the first Mimivirus virophage to be isolated in the Americas. Methods/results: Based on a phylogenetic analysis, SMBV belongs to group A of the putative Megavirales order, possibly a new virus related to Acanthamoeba polyphaga mimivirus (APMV). SMBV is the largest virus isolated in Brazil, with an average particle diameter about 574 nm. The SMBV genome contains 938 ORFs, of which nine are ORFans. The 1,213.6 kb SMBV genome is one of the largest genome of any group A Mimivirus described to date. Electron microscopy showed RNV particle accumulation near SMBV and APMV factories resulting in the production of defective SMBV and APMV particles and decreasing the infectivity of these two viruses by several logs. Conclusion: This discovery expands our knowledge of Mimiviridae evolution and ecology. [ABSTRACT FROM AUTHOR]

To investigate circulation of mimiviruses in the Amazon Region of Brazil, we surveyed 513 serum samples from domestic and wild mammals. Neutralizing antibodies were detected in 15 sample pools, and mimivirus DNA was detected in 9 pools of serum from capuchin monkeys and in 16 pools of serum from cattle. [ABSTRACT FROM AUTHOR]

Two fosmid libraries, totaling 13,200 clones, were obtained from bioreactor sludge of petroleum refinery wastewater treatment system. The library screening based on PCR and biological activity assays revealed more than 400 positive clones for phenol degradation. From these, 100 clones were randomly selected for pyrosequencing in order to evaluate the genetic potential of the microorganisms present in wastewater treatment plant for biodegradation, focusing mainly on novel genes and pathways of phenol and aromatic compound degradation. The sequence analysis of selected clones yielded 129,635 reads at an estimated 17-fold coverage. The phylogenetic analysis showed Burkholderiales and Rhodocyclales as the most abundant orders among the selected fosmid clones. The MG-RAST analysis revealed a broad metabolic profile with important functions for wastewater treatment, including metabolism of aromatic compounds, nitrogen, sulphur and phosphorus. The predicted 2,276 proteins included phenol hydroxylases and cathecol 2,3- dioxygenases, involved in the catabolism of aromatic compounds, such as phenol, byphenol, benzoate and phenylpropanoid. The sequencing of one fosmid insert of 33 kb unraveled the gene that permitted the host, Escherichia coli EPI300, to grow in the presence of aromatic compounds. Additionally, the comparison of the whole fosmid sequence against bacterial genomes deposited in GenBank showed that about 90% of sequence showed no identity to known sequences of Proteobacteria deposited in the NCBI database. This study surveyed the functional potential of fosmid clones for aromatic compound degradation and contributed to our knowledge of the biodegradative capacity and pathways of microbial assemblages present in refinery wastewater treatment system. [ABSTRACT FROM AUTHOR]

The aim of this study was to verify the possible interactions between ethanol extracts of Amburana cearensis A. C. Smith and Anadenanthera macrocarpa (Benth.) Brenan, combined with six antimicrobial drugs against multiresistant strains of Staphylococcus aureus and Escherichia coli isolated from humans. The antibacterial activity of the extracts was determined using the minimum inhibitory concentration (MIC). The microdilution assay was performed to verify the interactions between the natural products and the antibiotics using a subinhibitory concentration. The activity of amikacin associated with the extract of Anadenanthera macrocarpa against EC 27 was enhanced, demonstrating an MIC reduction from 128 to 4 µg/mL. Among the β-lactams, no potentiation on its activity was observed, with exception to the antagonism of the natural products with ampicillin against S. aureus 358. [ABSTRACT FROM AUTHOR]

The Leishmania species present a genetic homology that ranges from 69 to 90%. Because of this homology, heterologous antigens have been used in the immunodiagnosis and vaccine development against Leishmania infections. In the current work, we describe the identification of species-specific and cross-reactive antigens among several New World Leishmania species, using symptomatic and asymptomatic naturally Leishmania chagasi-infected dog sera. Soluble antigens from five strains of New World Leishmania were separated by electrophoresis in SDS-PAGE and immunoblotted. Different proteins were uniquely recognized in the L. chagasi panel by either symptomatic or asymptomatic dog sera suggesting their use as markers for the progression of disease and diagnosis of the initial (sub-clinical) phase of the infection. Cross-reactive antigens were identified using heterologous antigenic panels ( L. amazonensis strains PH8 and BH6, L. guyanensis and L. braziliensis). L. guyanensis panel showed the highest cross-reactivity against L. chagasi specific antibodies, suggesting that proteins from this extract might be suitable for the diagnosis of visceral canine leishmaniasis. Interestingly, the 51 and 97 kDa proteins of Leishmania were widely recognized (77.8% to 100%) among all antigenic panels tested, supporting their potential use for immunodiagnosis. Finally, we identified several leishmanial antigens that might be useful for routine diagnosis and seroepidemiological studies of the visceral canine leishmaniasis. [ABSTRACT FROM AUTHOR]

InAs quantum dots grown by molecular-beam epitaxy on GaAs substrates are demonstrated to be suitable structures to achieve an optical emission in the 1.3-1.5-μm range. Their tuning towards such long wavelengths was made possible by combining an extreme reduction of the InAs growth rate and a fast growth of the GaAs cap layer at low temperature. Our results create perspectives for the fabrication of GaAs-based devices operating in the most important telecommunications window. [ABSTRACT FROM AUTHOR]

The aim of this study was to verify the possible interactions between ethanol extracts of Amburana cearensis A. C. Smith and Anadenanthera macrocarpa (Benth.) Brenan, combined with six antimicrobial drugs against multiresistant strains of Staphylococcus aureus and Escherichia coli isolated from humans. The antibacterial activity of the extracts was determined using the minimum inhibitory concentration (MIC). The microdilution assay was performed to verify the interactions between the natural products and the antibiotics using a subinhibitory concentration. The activity of amikacin associated with the extract of Anadenanthera macrocarpa against EC 27 was enhanced, demonstrating an MIC reduction from 128 to 4¿ ¿g/mL. Among the ß-lactams, no potentiation on its activity was observed, with exception to the antagonism of the natural products with ampicillin against S. aureus 358. [ABSTRACT FROM AUTHOR]