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A pullout analytical model is introduced to simulate the Double Edge Wedge Splitting (DEWS) test to obtain the tensile post-peak response of steel fiber reinforced concretes. One of the main barriers to the widespread utilization of FRC as a structural system is the anisotropy of the material. This augments the uncertainty of the material behavior (fibers random distribution and orientation in the bulk concrete), increases the dispersion of the test results, and requires the performance of characterization tests to check the residual tensile stresses at specific crack opening intervals. The characterization tests proposed in the literature (e.g., Barcelona, Montevideo, Wedge Splitting Test, EN 14651) are time-consuming and relatively complex, demanding careful preparation and hydraulic presses with data acquisition systems. This paper aims to contribute to the discussion of alternatives for FRC characterization procedures by the introduction of a pullout analytical model to predict FRC constitutive law based on DEWS tests. The pullout analytical model is calibrated with pullout tests considering straight and hooked-end steel fibers with different strengths, embedment lengths, inclinations, and diameters. A 3D digital model reproducing the experimental DEWS samples is developed, considering the fibers' randomness distribution, orientation, and wall effect. The analyses are compared with four different experimental tests. The results define a linear post-peak tensile constitutive law, considering the mean residual stress values at different COD values. The model was able to reproduce the specimens' production procedures and the fibers' distribution and orientation correctly. The results demonstrated a good agreement with the experimental data. [Display omitted] • Pullout analytical model for straight and hooked-end steel fibers. • 3D parametric digital model considering fibers random distribution and wall effect. • Prediction of DEWS tests considering the manufacturing process. • Determination of FRC linear tensile post-peak constitutive model. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pelleting improved the bulk density and enzymatic digestibility of corn stover. • Stover composition was not significantly altered by high moisture pelleting. • Pelleting decreased substrate surface area but increased protein accessibility. • Hydrolysis of cross-linking structures may occur during the pelleting process. Pelleting of lignocellulosic biomass to improve its transportation, storage and handling impacts subsequent processing and conversion. This work reports the role of high moisture pelleting in the enzymatic digestibility of corn stover prior to pretreatment, together with associated substrate characteristics. Pelleting increases the digestibility of unpretreated corn stover, from 8.2 to 15.5% glucan conversion, at 5% solid loading using 1 FPU Cellic® CTec2 per g solids. Compositional analysis indicates that loose and pelleted corn stover have similar non-dissolvable compositions, although their extractives are different. Enzymatic hydrolysis of corn stover after size reduction to normalize particle sizes and removal of extractives confirms that pelleting improves corn stover digestibility. Such differences may be explained by the decreased particle size, improved substrate accessibility, and hydrolysis of cross-linking structures induced by pelleting. These findings are useful for the development of processing schemes for sustainable and efficient use of lignocellulose. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the performances of Tanzania and Mombaça grasses intercropped with stylosanthes Campo Grande and Mineirão, and the proportion of legumes in the system over time. Eight treatments were evaluated: 1: Panicum maximum cv. Mombaça, 2: Panicum maximum cv. Tanzania, 3: Stylosanthes guianensis cv. Mineirão, 4: Stylosanthes macrocephala + capitata cv. Campo Grande, 5: Mombaça + Mineirão, 6: Mombaça + cv. Campo Grande, 7: Tanzania + cv. Mineirão, 8: Tanzania + cv. Campo Grande, studied in 4 cycles at two times of the year. The heights, the leaf/stems relation and the number of tiller of the grasses, cultures growth rate and the percentage of present legumes in the system were measured. No influence of the legumes under the characteristics of grass was observed. The legumes diminished the botanical composition of the pasture throughout the year. The performance of the grasses was affected by the time of the year and the structure of the plant for the management of the imposed residue height. The intercrop of Tanzania and Mombaça grasses with the stylosanthes Campo Grande and Mineirão, under intensive production system, was not sustainable. [ABSTRACT FROM AUTHOR]

• Corn stover pellets (300 g/L) were successfully liquefied without pretreatment. • Combination of enzyme and maleic acid liquefactions reduced yield stress 40 times. • Efficient mixing improved liquefaction by an order of magnitude. • Mimetic maleic acid cooking of biomass lowered subsequent inhibition of enzymes. The movement of solid material into and between unit operations within a biorefinery is a bottleneck in reaching design capacity, with formation of biomass slurries needed to introduce feedstock. Corn stover slurries have been achieved from dilute acid, pretreated materials resulting in slurry concentrations of up to about 150 g/L, above which flowability is compromised. We report a new strategy to liquefy corn stover at higher solids concentration (300 g/L) by initially cooking it with the enzyme mimetic maleic acid at 40 mM and 150 °C. This is followed by 6 h of enzymatic modification at 1 FPU (2.2 mg protein)/g solids, resulting in a yield stress of 171 Pa after 6 h and 58 Pa in 48 h compared to 6806 Pa for untreated stover. Mimetic treatment of corn stover pellets minimizes the inhibitory effect of xylo -oligomers on hydrolytic enzymes. This strategy allows for the delivery of solid lignocellulosic slurry into a pretreatment reactor by pumping, improving operability of a biorefinery. [ABSTRACT FROM AUTHOR]

Abstract: Organophosphorus-induced delayed neuropathy (OPIDN) is a neurodegenerative disorder characterised by ataxia progressing to paralysis with concomitant central and peripheral distal axonopathy. Symptoms of OPIDN in people include tingling of the hands and feet. This tingling is followed by sensory loss, progressive muscle weakness and flaccidity of the distal skeletal muscles of the lower and upper extremities and ataxia, which appear about 8–14days after exposure. Some organophosphorus compounds (OPs) that are still used in worldwide agriculture have potential to induce OPIDN, including methamidophos, trichlorfon, dichlorvos and chorpyrifos. This review summarizes experimental attempts to prevent and/or treat OPIDN and the different mechanisms involved in each approach. The initial mechanism associated with development of OPIDN is phosphorylation and inhibition of neuropathy target esterase (NTE). The phosphorylated enzyme undergoes a second reaction known as “aging” that results in the loss of one of the “R” groups bound to the phosphorus of the OP. A second mechanism involved in OPIDN is an imbalance in calcium homeostasis. This can lead to the activation of calcium-activated neutral protease and increases in calcium/calmodulin-dependent protein kinases. These events contribute to aberrant phosphorylation of cytoskeletal proteins and protein digestion in the terminal axon that can proceed similarly to Wallerian-type degeneration. Several experimental studies demonstrated alleviation of the signs and symptoms of OPIDN by restoring calcium balance. Other studies have used preadministration of NTE inhibitors, such as carbamates, thiocarbamates, sulfonyl fluorides and phosphinate to prevent OPIDN. Progress is being made, but there is yet no single specific treatment available for use in clinical practice to prevent or alleviate the severe effects of OPIDN. [Copyright &y& Elsevier]

The use of secondary metabolites with biological properties, such as flavonoids, has been increasingly documented. This work evaluates the in vitro antibiotic activity of two flavonoids: quercetin and isoquercetin. The microdilution broth test was used to measure antimicrobial activity against standard and multiresistant strains of E. coli and S. aureus and strains of Candida. These flavonoids were also tested for a modulatory effect on aminoglycoside antibiotics. The flavonoids studied did not show significant antibacterial activity, while only isoquercetin demonstrated notable antifungal activity, inhibiting the growth of Candida krusei at a concentration of 32 μg/mL. In relation to modifying activity, there was no potentiation of the antibiotics tested. Isoquercetin showed antagonism with all the aminoglycosides examined, considerably increasing their minimal inhibitory concentrations (MICs). In light of these results, more in-depth studies are necessary, aimed at standardizing the protocols of antibiotic assays, as well as evaluating the effect of test substances against other classes of antimicrobials. [ABSTRACT FROM AUTHOR]

Among the forage species cultivated in South America, the genus Urochloa is the most used, and the cultivar Marandu of U. brizantha is the most widely planted in Brazil. The objective of this study was to evaluate forage performance in association with Azospirillum brasilense , combined with nitrogen (N) fertilisation. The study was conducted under field conditions in Araguaína, Tocantins, in the central region of Brazil, between March 2016 and March 2017. Four N fertiliser rates (0, 12.5, 25 and 50 kg/ha of N per cutting cycle) were combined with two inoculation treatments (inoculated and non-inoculated), with evaluations carried out in three periods of the year (transition, dry and wet seasons). Marandu grass plants inoculated with A. brasilense had greater plant height, number of tillers and forage production than non-inoculated plants, regardless of the N rate. Inoculation with A. brasilense allowed a 20% reduction in N fertilisation. Our results indicate that inoculation with A. brasilense in Marandu grass, as well as increasing forage production, can help to mitigate the stresses caused by the dry season. Marandu grass is the most planted in Brazil, with great importance in the bovine productive chain. In our study, we sought to increase productivity and reduce nitrogen fertilization of this grass by association with plant growth promoting bacteria. We observed that, in addition to increased production and reduction of nitrogen fertilization, the association with these bacteria became a sustainable and beneficial practice in the dry period of the year. [ABSTRACT FROM AUTHOR]

Background: Epilepsy is one of the most prevalent neurological disorders. It remains medically intractable for about one-third of patients with focal epilepsy, for whom precise localization of the epileptogenic zone responsible for seizure initiation may be critical for successful surgery. Existing fMRI literature points to widespread network disturbances in functional connectivity. Per previous scalp and intracranial EEG studies and consistent with excessive local synchronization during interictal discharges, we hypothesized that, relative to same regions in healthy controls, epileptogenic foci would exhibit less chaotic dynamics, identifiable via entropic analyses of resting state fMRI time series.Methods: In order to first validate this hypothesis on a cohort of patients with known ground truth, here we test individuals with well-defined epileptogenic foci (left mesial temporal lobe epilepsy). We analyzed voxel-wise resting-state fMRI time-series using the autocorrelation function (ACF), an entropic measure of regulation and feedback, and performed follow-up seed-to-voxel functional connectivity analysis. Disruptions in connectivity of the region exhibiting abnormal dynamics were examined in relation to duration of epilepsy and patients' cognitive performance using a delayed verbal memory recall task.Results: ACF analysis revealed constrained (less chaotic) functional dynamics in left temporal lobe epilepsy patients, primarily localized to ipsilateral temporal pole, proximal to presumed focal points. Autocorrelation decay rates differentiated, with 100 % accuracy, between patients and healthy controls on a subject-by-subject basis within a leave-one-subject out classification framework. Regions identified via ACF analysis formed a less efficient network in patients, as compared to controls. Constrained dynamics were linked with locally increased and long-range decreased connectivity that, in turn, correlated significantly with impaired memory (local left temporal connectivity) and epilepsy duration (left temporal - posterior cingulate cortex connectivity).Conclusions: Our current results suggest that data driven functional MRI methods that target network dynamics hold promise in providing clinically valuable tools for identification of epileptic regions. [ABSTRACT FROM AUTHOR]

Impaired cerebrovascular reactivity (CVR), a predictive factor of imminent stroke, has been shown to be associated with carotid steno-occlusive disease. Magnetic resonance imaging (MRI) techniques, such as blood oxygenation level-dependent (BOLD) and arterial spin labeling (ASL), have emerged as promising noninvasive tools to evaluate altered CVR with whole-brain coverage, when combined with a vasoactive stimulus, such as respiratory task or injection of acetazolamide. Under normal cerebrovascular conditions, CVR has been shown to be globally and homogenously distributed between hemispheres, but with differences among cerebral regions. Such differences can be explained by anatomical specificities and different biochemical mechanisms responsible for vascular regulation. In patients with carotid steno-occlusive disease, studies have shown that MRI techniques can detect impaired CVR in brain tissue supplied by the affected artery. Moreover, resulting CVR estimations have been well correlated to those obtained with more established techniques, indicating that BOLD and ASL are robust and reliable methods to assess CVR in patients with cerebrovascular diseases. Therefore, the present paper aims to review recent studies which use BOLD and ASL to evaluate CVR, in healthy individuals and in patients with carotid steno-occlusive disease, providing a source of information regarding the obtained results and the methodological difficulties. [ABSTRACT FROM AUTHOR]

In cerrado regions, during the rainy season, the occurrence of drought periods that compromise essential functions related to the production of upland rice is very common. In order to explore drought tolerant materials, this study aimed to evaluate the productive aspects of upland rice lines under water stress conditions. The experiment was conducted in two years (2007 and 2008) in the experimental research station of Universidade Federal do Tocantins, Gurupi, Tocantins, Brazil, evaluating 20 upland rice strains, consisting of two parents (Puteca and Chorinho) and 18 F7 strains selected from 186 materials obtained from crossings between the parents. The spikelets sterility, one hundred grains weight, yield and drought susceptibility index (DSI), were evaluated. The Chorinho, CNA 102, CNA 121, CNA 161, CNA 179, CNA 212 and CNA 236 materials were superior in comparison to the other ones, with lower DSI values and higher yields in water stress conditions. From the selection of these lines, genes (or groups of genes) determining this drought tolerance may be found, aiming at the future release of commercial cultivars. [ABSTRACT FROM AUTHOR]

Background: Obstructive sleep apnea (OSA) is related to increased systemic inflammation and arterial hypertension. We hypothesize that OSA is frequent in patients with acute hypertensive intracerebral hemorrhage (ICH) and is related to the perihematoma edema. Methods: Thirty-two non-comatose patients with a hypertensive ICH underwent polysomnography in the acute phase. Perihematoma edema volume was measured on CT scans at admission, after 24 h (early control) and after 4–5 days (late control). The Spearman coefficient (rs) was used for correlations. Results: OSA occurred in 19 (59.4%) patients. The apnea-hypopnea index was correlated with relative edema at admission CT (rs = 0.40; p = 0.031), early CT (rs = 0.46; p = 0.011) and at late CT (rs = 0.59; p = 0.006). Conclusions: OSA is highly frequent during the acute phase of hypertensive ICH and is related to perihematoma edema. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Monocrotaline is a pyrrolizidine alkaloid present in plants of the Crotalaria species, which causes cytotoxicity and genotoxicity, including hepatotoxicity in animals and humans. It is metabolized by cytochrome P-450 in the liver to the alkylating agent dehydromonocrotaline. We evaluated the effects of monocrotaline and its metabolite on respiration, membrane potential and ATP levels in isolated rat liver mitochondria, and on respiratory chain complex I NADH oxidase activity in submitochondrial particles. Dehydromonocrotaline, but not the parent compound, showed a concentration-dependent inhibition of glutamate/malate-supported state 3 respiration (respiratory chain complex I), but did not affect succinate-supported respiration (complex II). Only dehydromonocrotaline dissipated mitochondrial membrane potential, depleted ATP, and inhibited complex I NADH oxidase activity (IC50=62.06μM) through a non-competitive type of inhibition (K I=8.1μM). Therefore, dehydromonocrotaline is an inhibitor of the activity of respiratory chain complex I NADH oxidase, an action potentially accounting for the well-documented monocrotaline''s hepatotoxicity to animals and humans. The mechanism probably involves change of the complex I conformation resulting from modification of cysteine thiol groups by the metabolite. [Copyright &y& Elsevier]

Simple Summary: Zilpaterol hydrochloride (ZH) is a β-adrenergic agonist (βAA) to be feed to feedlot cattle at a rate of 8.3 mg/kg during the final 20 to 40 d of the finishing period followed by a minimum 3 d withdrawal period. This compound has the potential to increase animal performance, improve carcass weight and meat yield. Although significant information regarding the effects of duration of ZH supplementation and days on the feed of Bos taurus cattle has been provided, there is a lack of information relative to its effects on Bos indicus breeds such as Nellore cattle. The current study aimed to evaluate the effects of the duration of ZH supplementation and DOF on performance, carcass characteristics, and saleable meat yield of Nellore bulls. The HCW and total saleable meat yield linearly increased with the duration of ZH supplementation as well as when the length of the feedlot period increased. We recommend supplementing ZH for Nellore bulls at least for 20 days, independently of days on feed, to improve hot carcass weight, hindquarter, and saleable meat yields of Nellore bulls. This study evaluated the effects of the duration of ZH supplementation and days on feed (DOF) on performance, carcass characteristics, and saleable meat yield of Nellore young bulls. The fixed effects included the duration (0, 20, 30, or 40 d before slaughter plus a 3 d ZH withdrawal period—8.33 mg of ZH/kg of DM) and DOF (90 and 117 d). Feed efficiency (G:F) linearly increased when the duration of ZH supplementation increased (p < 0.01). Nellore bulls fed ZH had greater HCW (p < 0.01), dressing percentage (p < 0.01) and Longissimus muscle area (LMA) (p < 0.01), but less 12th-rib fat (p = 0.04) than the control group. The hot carcass weight (HCW) (p < 0.01), and dressing percentage increased linearly (p < 0.01) with the increase of duration of ZH supplementation. The HCW, ossification, and 12th-rib fat increased with DOF (p < 0.01). The ZH supplemented group had most of the individual cuts of hindquarters and total saleable meat increased compared with the control. Zilpaterol hydrochloride was effective in improving hot carcass weight, hindquarter, and saleable meat yields of Nellore bulls when fed for at least 20 d before slaughter, independently of days on feed. [ABSTRACT FROM AUTHOR]