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Abstract: Purpose This study aimed to (1) quantify the chemical attributes associated with soil fertility and the different fractions of soil organic matter (SOM) under no-tillage (NT) system areas at different time intervals after burning, and (2) measure the impact of burning on soil fertility and organic carbon fractions by comparing the data obtained with information from areas before the action of fire (reference time). Methods Two areas managed under the NT system that were affected by fires in 2020 in the Cerrado biome were evaluated. The areas had different implementation times: the NT07 area was implemented 7 years ago, in the transition phase, and the NT19 area was implemented 19 years ago, in the consolidation phase. Samples collected at four different times after burning (20, 40, 60, and 80 d) were used. Results In the NT19 area, the highest levels of Ca2+, K+, total carbon, total nitrogen, total organic carbon, particulate, and mineral-associated carbon were quantified compared with the NT07 area in the surface layer. Polynomial regression analysis showed significant temporal variations in the contents of chemical attributes and organic fractions of the SOM, especially in the fractions with higher lability in the area of the system in the transition phase. Conclusion The effect of fire was greater in the superficial layer (first 0.10 m depth), wherein greater changes were observed in the chemical attributes and organic matter fractions of the soil compared to the underlying layer (0.10–0.20 m). Burning influenced the dynamics of certain nutrients and the compartmentalization of soil organic matter throughout the 80 days of evaluation. We believe that the evaluation and temporal monitoring of soils in areas affected by fire, both natural and anthropogenic, are essential. These areas are intended for food production. Highlights: i. The Cerrado biome was the most affected by fires in Brazil in 2020, affecting an area of ± 139,649 km2. Graphical Abstract:

Vitamins B6, B12, and folate are essential for the formation and maintenance of the human brain, but studies evaluating these vitamins with early childhood development (ECD) in children under 5 y are limited and controversial.

Small average differences in the left-right asymmetry of cerebral cortical thickness have been reported in individuals with autism spectrum disorder (ASD) compared to typically developing controls, affecting widespread cortical regions. The possible impacts of these regional alterations in terms of structural network effects have not previously been characterized. Inter-regional morphological covariance analysis can capture network connectivity between different cortical areas at the macroscale level. Here, we used cortical thickness data from 1455 individuals with ASD and 1560 controls, across 43 independent datasets of the ENIGMA consortium’s ASD Working Group, to assess hemispheric asymmetries of intra-individual structural covariance networks, using graph theory-based topological metrics. Compared with typical features of small-world architecture in controls, the ASD sample showed significantly altered average asymmetry of networks involving the fusiform, rostral middle frontal, and medial orbitofrontal cortex, involving higher randomization of the corresponding right-hemispheric networks in ASD. A network involving the superior frontal cortex showed decreased right-hemisphere randomization. Based on comparisons with meta-analyzed functional neuroimaging data, the altered connectivity asymmetry particularly affected networks that subserve executive functions, language-related and sensorimotor processes. These findings provide a network-level characterization of altered left-right brain asymmetry in ASD, based on a large combined sample. Altered asymmetrical brain development in ASD may be partly propagated among spatially distant regions through structural connectivity.

This article deals with the design of a digital current control applied to a variable-speed low inductance brushless dc (BLdc) motor drive. A robust static full-state feedback control law is determined by means of a convex optimization problem, subject to linear-matrix-inequality constraints. The optimization is used to achieve a fast time response with reduced overshoot under the parametric variation. Results from a 5 kW/48 V BLdc motor prototype is used to validate the proposed approach with a superior performance when compared to two other control strategies.

This article proposes a systematic state-space procedure to design an optimal discrete-time linear quadratic regulator applied to grid-forming converters. A comprehensive mathematical modeling of a voltage-sourced converter with an LC output filter is performed and a systematic way of including digital resonant compensators is addressed. The choice of weights is based on the minimization of selected transfer functions infinity norm, as well as on the stability margin and bandwidth. The effects of weighting on closed-loop transfer functions shape are analyzed and important points are discussed in order to establish a methodical way of choosing the weighting matrices. Experimental results are presented to validate the design and to demonstrate the system effectiveness with high loading and highly nonlinear balanced and unbalanced loads.

In this study, the microclimate changes in silvopastoral systems are quantified at different time and spatial scales and compared with single-pasture systems. The study was conducted in a silvopastoral system in São Carlos, Brazil (22°01' South and 47°53' West). The silvopastoral system consisted of grass pastures [Urochloa (sin. Brachiaria) decumbens cv. Basilik] lined with strips of native trees spaced at 17 m. Continuous microclimate measurements (air temperature, relative humidity, wind speed, and incident photosynthetically active radiation) were carried out from September 2010 to September 2012 at two positions of the silvopastoral system (2.0 and 8.5 m from the rows of trees) and at a pasture under full sunlight, located in an adjacent area. The soil moisture was monitored weekly from 24 March 2010 to 1 April 2012 at distances of 0.0, 2.0, 4.75, and 8.5 m from the rows of trees. The rows of native trees reduced wind speeds (46% reduction) and changed the photosynthetically active radiation incidence pattern on the pasture (up to 40% reduction of incidence at the point nearest to the trees). The combined action of these factors promoted thermal and air humidity changes on the pasture at the different points measured. With respect to soil moisture, there was greater soil moisture removal at the sampling points near the rows of native trees under the silvopastoral system, mainly due to enhanced exploration by tree roots at greater depths in dry spells or early dry periods, when compared with the midpoints between the rows. [ABSTRACT FROM AUTHOR]

ObjectiveTo evaluate the clinical features of obsessive-compulsive disorder (OCD) patients with comorbid tic disorders (TD) in a large, multicenter, clinical sample.MethodA cross-sectional study was conducted that included 813 consecutive OCD outpatients from the Brazilian OCD Research Consortium and used several instruments of assessment, including the Yale-Brown Obsessive-Compulsive Scale, the Dimensional Yale-Brown Obsessive-Compulsive Scale, the Yale Global Tic Severity Scale (YGTSS), the USP Sensory Phenomena Scale, and the Structured Clinical Interview for DSM-IV Axis I Disorders.ResultsThe sample mean current age was 34.9 years old (SE 0.54), and the mean age at obsessive-compulsive symptoms (OCS) onset was 12.8 years old (SE 0.27). Sensory phenomena were reported by 585 individuals (72% of the sample). The general lifetime prevalence of TD was 29.0% (n= 236), with 8.9% (n= 72) presenting Tourette syndrome, 17.3% (n= 141) chronic motor tic disorder, and 2.8% (n= 23) chronic vocal tic disorder. The mean tic severity score, according to the YGTSS, was 27.2 (SE 1.4) in the OCD + TD group. Compared to OCD patients without comorbid TD, those with TD (OCD + TD group, n= 236) were more likely to be males (49.2% vs. 38.5%, p < .005) and to present sensory phenomena and comorbidity with anxiety disorders in general: separation anxiety disorder, social phobia, specific phobia, generalized anxiety disorder, post-traumatic stress disorder, attention-deficit hyperactivity disorder, impulse control disorders in general, and skin picking. Also, the “aggressive,” “sexual/religious,” and “hoarding” symptom dimensions were more severe in the OCD + TD group.ConclusionTic-related OCD may constitute a particular subgroup of the disorder with specific phenotypical characteristics, but its neurobiological underpinnings remain to be fully disentangled.

ABSTRACTIntroduction:Findings suggest that obsessive-compulsive disorder (OCD) and related disorders, referred to as obsessive-compulsive spectrum disorders (OCSDs), are more common in patients with rheumatic fever (RF).Objectives:To determine whether RF or Sydenham's chorea increases the probability of anxiety disorders in the relatives of individuals with RF with and without SC.Methods:This was a case-control family study in which 98 probands and 389 first-degree relatives (FDRs) were assessed using structured psychiatric interviews. A Poisson regression model was used to determine whether the presence of any disorder in one family member influences the rate of disorders in the remaining family members.Results:Generalized anxiety disorder (GAD) occurred more frequently in the FDRs of RF probands than in those of control probands (P=.018). The presence of RF, GAD, or separation anxiety disorder in one family member significantly increased the chance of OCSDs in another member of the family.

The rates of bacterial growth in nature are often restricted by low concentrations of oxygen or carbon substrates. In the present study the metabolic properties of 24 isolates that had been isolated using various concentrations of 3‐chlorobenzoate, benzoate and oxygen as well as using continuous culture at high and low growth rates were determined to investigate the effects of these parameters on the metabolism of monoaromatic compounds. Bacteria were enriched from different sampling sites and subsequently isolated. In batch culture this was done both under low oxygen (2% O2) and air‐saturated concentrations. Chemostat enrichments were performed under either oxygen or 3‐chlorobenzoate limiting conditions. Bacteria metabolizing aromatics with gentisate or protocatechuate as intermediates (gp bacteria) as well as bacteria metabolizing aromatic compounds via catechols (cat bacteria) were isolated from batch cultures when either benzoate or 3CBA were used as C sources, regardless of the enrichment conditions applied. In contrast, enrichments performed in chemostats at low dilution rates resulted in gp‐type organisms only, whereas at high dilution rates cat‐type organisms were enriched, irrespective of the oxygen and 3‐chlorobenzoate concentration used during enrichment. It is noteworthy that the gp‐type of bacteria possessed relatively low μmaxvalues on 3CBA and benzoate along with relatively high substrate and oxygen affinities for these compounds. This is in contrast with cat‐type of bacteria, which seemed to be characterized by high maximum specific growth rates on the aromatic substrates and relatively high apparent half saturation constants. In contrast, bacteria degrading chlorobenzoate via gentisate or protocatechuate may possibly be better adapted to conditions leading to growth at reduced rates such as low oxygen and low substrate concentrations.

The rates of bacterial growth in nature are often restricted by low concentrations of oxygen or carbon substrates. In the present study the metabolic properties of 24 isolates that had been isolated using various concentrations of 3-chlorobenzoate, benzoate and oxygen as well as using continuous culture at high and low growth rates were determined to investigate the effects of these parameters on the metabolism of monoaromatic compounds. Bacteria were enriched from different sampling sites and subsequently isolated. In batch culture this was done both under low oxygen (2% O2) and air-saturated concentrations. Chemostat enrichments were performed under either oxygen or 3-chlorobenzoate limiting conditions. Bacteria metabolizing aromatics with gentisate or protocatechuate as intermediates (gp bacteria) as well as bacteria metabolizing aromatic compounds via catechols (cat bacteria) were isolated from batch cultures when either benzoate or 3CBA were used as C sources, regardless of the enrichment conditions applied. In contrast, enrichments performed in chemostats at low dilution rates resulted in gp-type organisms only, whereas at high dilution rates cat-type organisms were enriched, irrespective of the oxygen and 3-chlorobenzoate concentration used during enrichment. It is noteworthy that the gp-type of bacteria possessed relatively low μmaxvalues on 3CBA and benzoate along with relatively high substrate and oxygen affinities for these compounds. This is in contrast with cat-type of bacteria, which seemed to be characterized by high maximum specific growth rates on the aromatic substrates and relatively high apparent half saturation constants. In contrast, bacteria degrading chlorobenzoate via gentisate or protocatechuate may possibly be better adapted to conditions leading to growth at reduced rates such as low oxygen and low substrate concentrations.

Desulfovibrio salexigensstrain Mastl was isolated from the oxic/anoxic interface of a marine sediment. Growth under sulfate-reducing conditions was accompanied by polyglucose accumulation in the cell with every substrate tested. Highest polyglucose storage was found with glucose (0.8–1.0 g polyglucose (g protein)−1), but the growth rate with this substrate was very low (0.015 h−1). Anaerobically grown cells of strain Mastl exhibited immediate oxygen-dependent respiration. The endogenous oxygen reduction rate was proportional to the polyglucose content. The rate of aerobic respiration of pyruvate was also directly related to the polyglucose content indicating that this organism was only able to respire with oxygen as long as polyglucose was present. Maximum oxygen reduction rates were found at air saturating concentrations and were relatively low (3–50 nmol O2min−1(mg protein)−1). Catalase was constitutively present in anaerobically grown cells. When batch cultures were exposed to oxygen, growth ceased immediately and polyglucose was oxidized to acetate within 40–50 h. Like the oxygen reduction activity, the nitro blue tetrazolium (NBT)-reduction activity in these cells was proportional to the polyglucose content. Under anaerobic starvation conditions there was no correlation between the NBT-reduction activity and polyglucose concentration and polyglucose was degraded slowly within 240 h. The ecological significance of aerobic polyglucose consumption is discussed.

In the anaerobic fungus Neocallimastix sp. L2 fermentation of glucose proceeds via the Embden-Meyerhof-Parnas pathway. Enzyme activities leading to the formation of succinate, lactate, ethanol, and formate are associated with the cytoplasmic fraction. The enzymes ‘malic enzyme’, NAD(P)H: ferredoxin oxidoreductase, pyruvate: ferredoxin oxidoreductase, hydrogenase, acetate: succinate CoA transferase and succinate thiokinase leading to the formation of H2, CO2, acetate, and ATP are localized in microbodies. Thus, these organelles are identified as hydrogenosomes. In addition, the microbodies contain the O2-scavenging enzymes NADH- and NADPH oxidase, while NAD(P)H peroxidase, catalase, or superoxide dismutase could not be detected. In cell-free extracts from zoospores of Neocallimastix sp. L2 the specific activities of hydrogenosomal enzymes as well as the quantities of these proteins are 2- to 6-fold higher than in mycelium extracts. These findings suggest that hydrogenosomes perform an important role-especially in zoospores — as H2-evolving, ATP-generating and O2-scavenging organelles.

To test conjunctival swabs from patients with laboratory-confirmed severe forms of coronavirus disease 2019 (COVID-19) for the presence of SARS-CoV-2 on real-time reverse-transcription polymerase chain reaction (rRT-PCR).

Fatigue is a mechanical engineering field which has been well studied in recent years. This phenomenon is responsible for causing the great majority of mechanical failures in machine elements. Fatigue analysis in a complex piece with the purpose of determining its durability becomes very complicated when it is performed by means of analytical calculations without the aid of software. Thus, the finite element method, which is studied in several areas and is constantly growing, is the ideal tool for the verification of possible failures due to fatigue in heterogeneous components. This paper offers a numerical simulation by finite element method using the software ANSYS of a hydrogenerator rotor which has presented some cracks. As the manifestation of such defect in hydroelectric plant rotors is not common, it requires a detailed study. The results obtained from this study showed that the cracks in the hydrogenerator rotor have arisen due to fatigue. It has been demonstrated that the method employed is very accurate when it is used correctly and that it provides results which represent reality. Moreover, improved solutions were suggested in order to enlarge the fatigue life of hydrogenerator rotor.