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Copyright of Ciência & Trópico (03042685) is the property of Fundacao Joaquim Nabuco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To take structure information into consideration, we propose a fractional-order image denoising model based on structure tensor. The existence and uniqueness of solution is proved. Furthermore, we also propose an alternating direction implicit (ADI) scheme of this model to find numerical solution and keep the stability of algorithm. Unconditional stability and convergence of this scheme is proved. Moreover, several numerical tests show that the proposed model can improve the denoising results of some published denoising models. [ABSTRACT FROM AUTHOR]

In this study a group of selected transformation kinetics equations is applied to describe the isothermal ferritic transformation in austempered ductile iron (ADI). A series of dilatometric tests has been carried out on ADI at different temperatures. The obtained experimental data are utilized to determine the parameter values of the considered kinetic equations. It is found that the transformation kinetics models by Starink, Austin and Rickett are substantially more effective at describing the ferritic transformation in ADI than the much celebrated Johnson-Mehl-Avrami-Kolmogorov (JMAK) equation. Furthermore, it is demonstrated that evaluating the kinetic parameters using the least squares method instead of calculating them from vastly used formulas can significantly improve the accuracy of the JMAK model's predictions. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we propose an alternating direction implicit (ADI) scheme of a fractional-order diffusion tensor image (DTI) registration model. Furthermore, compatibility, stability and convergence of ADI scheme are proved. Moreover, five numerical tests are also performed to show the efficiency of this scheme. [ABSTRACT FROM AUTHOR]

Two-step austempering treatment has been carried out by heating FCD at an austenitising temperature of 900 °C for 60 minutes, then FCD has been quenched in 50% NaNO3 + 50% KNO3 salt solution at an austempering temperature of 260 °C with 5 minutes and 15 minutes holding time, finally, the FCD has been reheated for 60 minutes. It has caused an improved tensile strength with increasing holding time at 260 °C. The treatment with 15-minute holding time generated the highest tensile strength of 621.65 N/mm², while the one with 5-minute holding time has yielded the lowest one of 548.15 N/mm². The microstructure of material held for 5 minutes has consisted of an austenite matrix with a small amount of coarse-grained acicular ferrite matrix, whereas the treatment with 15 minute holding time has resulted in a drop in the amount of austenite matrix and an increase in the amount of fine-grained acicular ferrite matrix. A rise in the amount and fineness of acicular ferrite matrix has brought improved tensile strength and ductility. The material subjected to the treatment with 15 minute holding time had the greatest ductility of 12%. The raw material and the material with 5 minute holding time had brittle fracture since their fracture surface has been flat and occurred by cleavage. [ABSTRACT FROM AUTHOR]

This paper considers the important factors of the production of high-strength ADI (Austempered Ductile Iron); namely, the austenitization stage during heat treatment. The two series of ADI with different initial microstructures were taken into consideration in this work. Experiments were carried out for castings with a 25-mm-walled thickness. Variable techniques (OM, SEM, dilatometry, DSC, Variable Magnetic Field, hardness, and impact strength measurements) were used for investigations of the influence of austenitization time on austempering transformation kinetics and structure in austempered ductile iron. The outcome of this work indicates that the austenitizing temperature has a very significant impact on structure homogeneity and the resultant mechanical properties. It has been shown that the homogeneity of the metallic matrix of the ADI microstructure strongly depends on the austenitizing temperature and the initial microstructure of the spheroidal cast irons (mainly through the number of graphite nodules). In addition, this work shows the role of the austenitization temperature on the formation of Mg–Cu precipitations in ADI. [ABSTRACT FROM AUTHOR]

Highlights • This is the first report on nitrate and nitrite dietary intake from meat samples. • Quantification of nitrate and nitrite was done using an optimized RP-HPLC methodology. • Nitrate and nitrite were detected simultaneously in a 12-min sample run. • Estimated dietary intake (EDI) calculated using food balance sheets and a 24-h diet recall study. • The EDI of nitrite from meat consumption exceeded the established acceptable daily intake. Abstract To assess the risk posed by meat consumption to the Fiji and Pacific populace, the present study reports nitrate and nitrite in meat. Twelve commercially available meat products, with a total of 210 fresh and processed meat samples, were analysed for nitrate and nitrite by an optimised RP-HPLC technique with isocratic elution using n-octylamine in 20.0% methanol at pH 6.60. The nitrate content in the meat samples ranged from 0.00 to 124 mg kg−1 whereas the nitrite ranged from 0.00 to 164 mg kg−1. The study shows that the nitrate and nitrite contents of meat samples in Fiji were below the maximum level proposed by European Union legislation but above the limit set by Food Standards Australia and New Zealand (FSANZ). The estimated dietary intake of nitrate and nitrite was calculated from a 24-h diet recall study as well as from Fiji's food balance sheets. [ABSTRACT FROM AUTHOR]

Ductile iron camshafts low alloyed with 0.2 and 0.3 wt % vanadium were produced by one of the largest manufacturers of the ductile iron camshafts in México “ARBOMEX S.A de C.V” by a phenolic urethane no-bake sand mold casting method. During functioning, camshafts are subject to bending and torsional stresses, and the lobe surfaces are highly loaded. Thus, high toughness and wear resistance are essential for this component. In this work, two austempering ductile iron heat treatments were evaluated to increase the mechanical properties of tensile strength, hardness, and toughness of the ductile iron camshaft low alloyed with vanadium. The austempering process was held at 265 and 305 °C and austempering times of 30, 60, 90, and 120 min. The volume fraction of high-carbon austenite was determined for the heat treatment conditions by XRD measurements. The ausferritic matrix was determined in 90 min for both austempering temperatures, having a good agreement with the microstructural and hardness evolution as the austempering time increased. The mechanical properties of tensile strength, hardness, and toughness were evaluated from samples obtained from the camshaft and the standard Keel block. The highest mechanical properties were obtained for the austempering heat treatment of 265 °C for 90 min for the ADI containing 0.3 wt % V. The tensile and yield strength were 1200 and 1051 MPa, respectively, while the hardness and the energy impact values were of 47 HRC and 26 J; these values are in the range expected for an ADI grade 3.

Prolonged exposure to low levels of dietary contaminants is a context in modern life that could alter organ physiology gradually. Here, we aimed to investigate the impact of continuous exposure to acceptable daily intake (ADI) and non-observable adverse effect level (NOAEL) of glyphosate from gestation to adulthood using C57BL/6J mice and incorporating these levels into their food pellets. From adulthood, we analyzed neurophysiological and neuro-glia cellular adaptations in male and female animals. Using ex-vivo hippocampal slice electrophysiology, we found a reduced efficacy of Schaffer collateral-to-CA1 excitatory synapses in glyphosate-exposed dietary conditions, with ADI and NOAEL dose-dependent effects. Short-term facilitation of excitatory synaptic transmission was specifically increased in NOAEL conditions, with a predominant influence in males, suggesting a reduced probability of neurotransmitter release. Long-term synaptic potentiation (LTP) was decreased in NOAEL-exposed mice. Next, we explore whether these neurophysiological modifications are associated with neuro-glia changes in the somatosensory cortex and hippocampus. High-resolution confocal microscopy analyses unveil a dose-dependent increased density of excitatory Vglut1+ Homer1+ synapses. Microglial Iba1+ cells displayed a shortening of their ramifications, a sign of cellular reactivity that was more pronounced in males at NOAEL levels. The morphology of GFAP+ astrocytes was generally not modified. Finally, we asked whether mouse-specific cross-correlations exist among all data sets generated. This examination included the novel object recognition (NOR) test performed before ex vivo functional and immunohistochemical examinations. We report a negative linear regression between the number of synapses and NOR or LTP maintenance when plotting ADI and NOAEL datasets. These results outline synaptic and microglial cell adaptations resulting from prenatal and continuous dietary low levels of glyphosate, discernible in, but not limited to, adult males exposed to the NOAEL. We discuss the potential significance of these findings to real-world consumer situations and long-term brain resilience. [Display omitted] • Dietary exposure to low glyphosate levels from prenatal to adulthood prompts neuro-glial adjustments. • In adults, synaptic function and number are modified mainly at NOAEL glyphosate compared to ADI. • Reduced microglial cell ramifications hint at activation, mainly at NOAEL dose. • These results support a framework highlighting a long-term risk of brain frailty due to continuous contaminant exposure. [ABSTRACT FROM AUTHOR]

Serendipity berry plant (Dioscoreophyllum cumminsii (Stapf) Diels) is the source of a naturally sweet protein referred to as monellin. The safety of serendipity berry sweet protein (SBSP) containing single polypeptide monellin (MON) expressed in Komagataella phaffii (formerly Pichia pastoris) and produced via precision fermentation was examined comprehensively through assessments of in vitro and in silico protein digestion , in silico allergenicity, in vitro genotoxicity (reverse mutation and mammalian micronucleus assays), and 14-day and 90-day oral (dietary) toxicity studies in rats. There was no indication of allergenicity for SBSP in the in silico analyses. Results from both in vitro and in silico protein digestibility assessments indicated that SBSP is digested upon ingestion and would therefore be unlikely to pose a toxigenic or allergenic risk to consumers. SBSP was non-genotoxic in in vitro assays and showed no adverse effects in the 14-day or 90-day toxicity studies up to the highest dose tested. The 90-day toxicity study supports a NOAEL for SBSP of 1954 mg/kg bw/day, which corresponds to a NOAEL for MON of 408 mg/kg bw/day. • Serendipity Berry Sweet Protein can be used as a sweetener in food and beverages. • Serendipity Berry Sweet Protein is digestible and not a toxigenic/allergenic risk. • Serendipity Berry Sweet Protein was non-genotoxic. • Serendipity Berry Sweet Protein 90 day oral no adverse effect level of 1954 mg/kg/d. • Oobli is producing the Serendipity Berry Sweet Protein via precision fermentation. [ABSTRACT FROM AUTHOR]

Austempered Ductile Iron (ADI) is a class of ductile iron subjected to a two-step heat treatment process – austenitization and austempering. The heat treatment gives to ADI a high value of tensile strength and an especially good strength-to-weight ratio. However, designers in most cases are unfamiliar with this material that can compete favorably with steel and aluminum castings, weldments and forgings. The high tensile strength of ADI is the result of its unique ausferrite microstructure. In this paper, an investigation of the influence of the austempering temperature on the tensile strength of the ADI samples is presented.

The paper presents results of the wear tests of chain wheels made of austempered ductile iron with various content of residual austenite. The aim of this study was to demonstrate the impact of the dynamic surface treatment (shot peening) on wear properties of surface layers of the chain wheels tested that were subjected to the action of quartz abrasive. Apart from determining the value of the abrasive wear, examinations of the magnetic phase content in the microstructure were carried out and plots of hardness of the surface layer as a function of the distance from the surface and microstructure of the materials were prepared. Based on the results, the following was found: an increase in the abrasive wear and a reduction in the hardness of the surface layer of chain wheels subjected to shot peening, as well as reduction of susceptibility to negative action of the shot for cast irons with the structure of upper ausferrite.

A person is forced to travel constantly throughout its entire life. The more modern the society, the greater the pace of life, and the greater the need to be present in many places that are distant from each other. Rail transport occupies second place in this regard, after air transport. This means of transportation has many advantages, however the time of travel requires continuous improvement, in particular, to match the competition. One factor limiting the speed of travel is inter-operation between the wheels – rail kinematic pair. When rolling on a rail, a wheel is subject to wear, which unavoidably leads to its degradation. Frequent damage to both the wheel and the rail necessitates consideration of this problem. Because any changes to the rail are very expensive and time-consuming, this paper focuses on possible changes to the wheel.

The factors that affect the value of parsley for consumption include its taste, flavour and dietary utility (vitamins C and E, β-carotene, potassium, calcium, phosphorus and iron, raw fibre, proteins) as well as the content of hazardous substances, especially nitrogen compounds. A study was carried out in 2013–2015 to determine the effect of the cultivation technology and storage on the safety of parsley intended for processing. The study material was taken from an experiment where the following fertilisers were applied to the ground: nitrogen (0, 40, 80, 120 kg N∙ha−1) and magnesium (0; 30 kg Mg∙ha−1). Parsley roots were stored for six months in a storage room at +1°C and RH 95%. The content of nitrates (V) and (III) was determined by the ion selective method immediately after the harvest and after storage in parsley roots.

Individuals’ behaviors are regulated by how they perceive themselves and their surroundings. Learning that encourages students to be active will provide more effective environment to facilitate them to achieve predetermined learning objectives. It is very important to identify college students’ perception and investigate to what extent they can understand learning strategies that are being implemented. This research was a descriptive quantitative research which involved 142 biology education students. Two questionnaires were distributed to obtain students’ perception on the implementation of Reading Questioning and Answering (RQA) and Argument Driven Inqury (ADI) learning strategies. As to collect more data, observation and interviews were also conducted. Research findings indicate that (1) 38,32% of the students have ever heard about RQA, but only 18,60 of them have experienced learning biology with RQA; (2) around 24,26% of the students are quite familiar with ADI, however, only 9,45% have been taught using the strategy.

Studies were carried out to determine the effect of heat treatment parameters on the plastic properties of unalloyed ausferritic ductile iron, such as the elongation and toughness at ambient temperature and at – 60 °C. The effect of austenitizing temperature (850, 900 and 950°C) and ausferritizing time (5 - 180 min.) at a temperature of 360°C was also discussed. The next step covered investigations of a relationship that is believed to exist between the temperature (270, 300, 330, 360 and 390 °C) and time (5, 10, 30, 60, 90, 120, 150, 180, 240 min.) of the austempering treatment and the mechanical properties of unalloyed ausferritic ductile iron, when the austenitizing temperature is 950°C. The “process window” was calculated for the ADI characterized by high toughness corresponding to the EN-GJS-800-10-RT and EN-GJS-900-8 grades according to EN-PN 1564 and to other high-strength grades included in this standard. Low-alloyed cast iron with the nodular graphite is an excellent starting material for the technological design of all the ausferritic ductile iron grades included in the PN-EN-1624 standard. The examined cast iron is characterized by high mechanical properties stable within the entire range of heat treatment parameters.

The objective of studies presented in this publication was structuring of research knowledge about the ADI functional properties and changes in these properties due to material treatment. The results obtained were an outcome of research on the selection of a format of knowledge representation that would be useful in further work aiming at the design, application and implementation of an effective system supporting the decisions of a technologist concerning the choice of a suitable material (ADI in this case) and appropriate treatment process (if necessary). ALSV(FD) logic allows easy modelling of knowledge, which should let addressees of the target system carry out knowledge modelling by themselves. The expressiveness of ALSV (FD) logic allows recording the values of attributes from the scope of the modelled domain regarding ADI, which is undoubtedly an advantage in the context of further use of the logic. Yet, although the logic by itself does not allow creating the rules of knowledge, it may form a basis for the XTT format that is rule-based notation. The difficulty in the use of XTT format for knowledge modelling is acceptable, but formalism is not suitable for the discovery of rules, and therefore the knowledge of technologist is required to determine the impact of process parameters on values that are functional properties of ADI. The characteristics of ALSV(FD) logic and XTT formalism, described in this article, cover the most important aspects of a broadly discussed, full evaluation of the applicability of these solutions in the construction of a system supporting the decisions of a technologist.

Austempered ductile iron (ADI) is a revolutionary material with high strength and hardness combined with excellent ductility and toughness. The discovery of a two-step austempering process has resulted in superior combination of all the mechanical properties. Therefore, ADI has many different applications in varying fields. One notable application of ADI is in transmission components for new energy vehicles. As the automotive continues to develop, ADI transmission components with higher damping properties are required, because the damping properties of ADI affect the vibration and noise of the transmission system. However, the mechanism behind the damping of ADI, as well as a full characterisation of the damping properties, has not been thoroughly investigated in the literature. Therefore, it is necessary to reveal the influencing factors and mechanism of the damping properties of ADI. In this paper, the effect of first-step austempering temperature on the microstructure, mechanical properties, and damping properties of ADI was investigated. The results revealed that the tensile strength, yield strength, and elongation of ADI all initially increased, until reaching a global maximum value (1320 MPa, 1230 MPa, and 13.2%, respectively) when the first-step austempering temperature was 280 °C, followed by a decrease in value. Interestingly, the impact energy of ADI initially decreased before reaching a global minimum and then increasing to a maximum value of 93.5 J, when the first-step austempering temperature reached 320 °C. With increasing strain amplitude, the internal friction values (Q ^−1 ) of ADI treated with different first-step austempering temperatures all increased gradually, and the Q ^−1 values of ADI with first-step austempering temperatures of 240 and 260 °C were higher than those of other samples. Moreover, the damping properties of ADI varied with frequency with obvious S-K peaks and Ge peaks.

Austempered Ductile Iron (ADI) is widely implemented to achieve lightweight and optimized components in power transmissions (e.g., internal gear in planetary stages), by substituting steel castings or a combination of Ductile Iron and steel-assembled structures. In this paper, the contact fatigue of two ADI grades (ADI J/S900-8; ADI J/S1200-3) is investigated by disk-on-disk tests. The disk-on-disk contact is an analogy model of the tooth contact and represents the tribological conditions at a specific point on the path of contact. The experimental results cover the endurance limit as well as the short time fatigue behavior for both ADI variants. In addition, the pitting characteristics and microstructural changes are analyzed in order to get a further understanding of the fatigue behavior of ADI.

Samples of ductile cast irons alloyed with Cu, Cu-Ni and Cu-Ni-Mo were austempered, borided and boro-austempered and characterized for hardness and micro-adhesive wear behavior. The kinetics of layer formation was also studied. The boriding method used was molten borax bath, in periods of 2 and 4 hours at temperatures of 850, 900 and 950 ºC. The direct austempering treatment was performed immediately following the boriding treatment (from 850, 900 and 950 ºC) using molten salt baths at temperatures of 240, 300 and 360 ºC for 4 hours (boro-austempering treatment). For comparative purposes, the conventional austempering treatment was also conducted. Optical microscopy, scanning electron microscopy, Brinell hardness measurements (on the substrate) and Vickers (on the layers) were performed, along with micro-adhesive wear tests. The boriding treatment resulted in the formation of high hardness layers, in the range of 1450 to 1750 HV, with high wear resistance. The wear resistance of borided and boro-austempered samples were increased by 40 times when compared to as cast or austempered samples, indicating the high efficiency of this type of treatment in increasing the wear resistance of this material.

Introduction: Living in disadvantaged neighborhoods has been shown to result in worse healthcare outcomes. The Area Deprivation Index (ADI) is a metric that ranks neighborhoods by socioeconomic disadvantage utilizing numerous factors including income, education, employment, and housing quality., Methods: A retrospective review of all patients who underwent surveillance in an APP-led head and neck cancer survivorship clinic from Dec 2016 to Oct 2020 at an academic tertiary care center were included. Tumor characteristics, visit frequency, recurrence, number of missed appointments, loss of follow up, and ADI scores were collected., Results: 543 patients were included in the study. A majority were male (69.9 %) and white race (84.9 %) with an average age of 64.6 years old. Average ADI national percentile score was 71.6(range: 17 to 100). ADI national percentile score was not predictive of tumor characteristics at initial presentation: lymphovascular invasion (p = 0.940; OR 1.0 [95 % CI: 0.9 to 1.1]), extranodal extension (p = 0.576; OR 1.0 [95 % CI: 0.9 to 1.2]), positive margins (p = 0.069; OR 0.9 [95 % CI: 0.9 to 1.0]). ADI national percentile score was not significantly correlated with loss to follow up (p = 0.153; OR 1.2 [95 % CI: 0.9 to 1.7] or cancer recurrence (p = 0.594; OR 1.0 [95 % CI: 0.9 to 1.1]). Missing one or more clinic visits was correlated with loss to follow up (p = 0.029; OR 13.1 [95 % CI: 1.3 to 131.7]., Conclusion: Living in a disadvantaged neighborhood did not correlate with negative tumor characteristics, loss to follow up, or recurrence within an APP-led survivorship head and neck cancer clinic., Competing Interests: Declaration of competing interest None., (Copyright © 2023. Published by Elsevier Inc.)

Area-level measures of the social exposome provide powerful tools to understand how context contributes to health disparities. Due to the geographic phenomenon of the modifiable aerial unit problem, the geographic level at which the index is constructed can threaten it utility. Previous work indicates that using smaller geographic levels lead to increased measurement precision which may result in closer alignment to policies that directly address health disparities. To provide an illustrative example of this phenomenon, we use Medicare 100% Fee-for Service hospitalization claims data to evaluate the association between area-level disadvantage and 30-day readmissions when the Area Deprivation Index (ADI) is constructed at different geographic levels. When area-level disadvantage is summarized at the "neighborhood" census block group-the study's smallest geographic level-there was a 20% higher odds of readmissions for those living in the top 20% most disadvantaged neighborhoods compared to those living in the lowest 80% neighborhoods nationwide. Yet, evidence for an association with readmissions was not found when neighborhood disadvantaged was summarized at larger geographic levels. Smaller geographic levels appear most optimal to capture these effects. In order to provide publicly available data that is truly publicly useable, greater attention in providing small area health data is needed., Competing Interests: Disclosure statement No potential conflict of interest was reported by the authors.

The aim of this study is to develop computer tools for calculation of the Fe - Fe3C phase equilibrium diagram. The phase equilibrium diagram is of fundamental importance in materials science and heat treatment processes of ferrous alloys. It enables prediction of carbon steel microstructure in the annealed condition, and facilitates selection of proper temperature for the heat treatment process. Choosing the right values of the heat treatment process parameters is essential in the production of Austempered Ductile Iron (ADI).

Abstract The austempered ductile iron (ADI) with carbides in its microstructure, commonly known as CADI, is a relatively new variant of ductile iron intended to resist abrasive wear in different tribosystems by selecting the appropriate casting procedure, chemical composition and heat treatment. In this case, the rolling contact fatigue (RCF) behavior of CADI with two heat treatments was compared to that of ADI to evaluate its potential use as an alternative material for machine parts subjected to point or line rolling/sliding contact fatigue conditions. The RCF tests were done in a flat washer type testing machine under contact conditions (load, roughness, lubricant and velocity) leading to contact of micro-asperities. When compared to ADI, the microstructure of CADI has similar nodularity and nodule size, but the nodule count is lower because part of the carbon is combined in the form of carbides. While having similar hardness and failure appearance, CADI RCF resistance was higher than that of ADI. It was observed that the nodules at or near the surface work as crack nucleation sites and then, when replacing part of the graphite content with carbides the load carrying capacity and the RCF resistance are improved with respect to those of ADI. Highlights • Heterogeneous materials under RCF perform different than homogeneous materials. • In general, CADI performed better than ADI under RCF conditions. • Compliant inclusions as micro-voids and graphite are very harmful for RCF life. • Carbide inclusions are less harmful than graphite for RCF performance. • Carbide reinforcement increased hardness and load carrying capacity. [ABSTRACT FROM AUTHOR]

Abstract: Since the invention by Peaceman and Rachford, more than 60 years ago, of the well celebrated ADI finite difference scheme for parabolic initial-boundary problems on rectangular regions, many papers have been concerned with prescribing the boundary values for the intermediate approximations at half time levels in the case of nonzero Dirichlet boundary conditions. In the present paper, for variable coefficient parabolic problems and time-stepsize sufficiently small, we prove second order accuracy in the discrete norm of the ADI finite difference scheme in which the intermediate approximations do not involve the so called "perturbation term". As a byproduct of our stability analysis we also show that, for variable coefficients and time-stepsize sufficiently small, the ADI scheme with the perturbation term converges with order two in the discrete norm. Our convergence results generalize previous results obtained for the heat equation. [ABSTRACT FROM AUTHOR]

The objective of this work stems from the environmentally assisted embrittlement suffered by austempered ductile iron (ADI) when its surface is submerged in water. This phenomenon leads to a drop in elongation and ultimate tensile strength of about 75% and 10%, respectively, while the 0.2% offset strain stress remains unaffected. Heat-treating a high Si steel, an ausferritic matrix similar to that present in the ADI under study is obtained, yielding giving a very good combination of tensile strength and elongation. In this manner, it was possible to examine the influence of the metallic matrix such as that present in ADI, though without nodules and cell boundaries, also called last to freeze zones (LTF). Tensile test evaluations on ADI and steel samples under dry and wet conditions were carried out. Additionally, a very specific test, introducing surface cracks, was conducted with the purpose of expanding the current knowledge on this particular kind of fracture. Earlier investigations on ADI have suggested that the process of embrittlement starts in a surface crack generated at the early stages of plastic deformation in LTF zones, which results from the solidification process, where pores, inclusions and unreacted austenite are present. In this manner, water penetrates and weakens the material strength, making the crack grow very fast and leading to an instantaneous samples failure. The main results obtained in this work include the confirmation of the deleterious effect of the LTF zones in the embrittlement process and the fracture surface analysis showing characteristic features of this kind of failure. [ABSTRACT FROM AUTHOR]

Steviol glycoside sweeteners are extracted and purified from the Stevia rebaudiana Bertoni plant, a member of the Asteraceae (Compositae) family that is native to South America, where it has been used for its sweet properties for hundreds of years. With continued increasing rates of obesity, diabetes, and other related comorbidities, in conjunction with global public policies calling for reductions in sugar intake as a means to help curb these issues, low- and no-calorie sweeteners (LNCSs, also known as high-potency sweeteners) such as stevia are gaining interest among consumers and food manufacturers. This appeal is related to stevia being plant-based, zero calorie and with a sweet taste that is 50-350 times sweeter than sugar, making it an excellent choice for use in sugar- and calorie-reduced food and beverage products. Despite the fact that the safety of stevia has been affirmed by several food regulatory and safety authorities around the world, insufficient education about stevia's safety and benefits, including continuing concern with regard to the safety of LNCSs in general, deters health professionals and consumers from recommending or using stevia. Therefore, the aim of this review and the stevia symposium that preceded this review at the ASN's annual conference in 2017 was to examine, in a comprehensive manner, the state of the science for stevia, its safety and potential health benefits, and future research and application. Topics covered included metabolism, safety and acceptable intake, dietary exposure, impact on blood glucose and insulin concentrations, energy intake and weight management, blood pressure, dental caries, naturality and processing, taste and sensory properties, regulatory status, consumer insights, and market trends. Data for stevia are limited in the case of energy intake and weight management as well as for the gut microbiome; therefore, the broader literature on LNCSs was reviewed at the symposium and therefore is also included in this review. [ABSTRACT FROM AUTHOR]

Nitrate and nitrite content was determined on a total of 900 samples of vegetables and cured meat and the nitrite and nitrate exposure assessment was evaluated for central Italy population based on the food consumption data reported by the national dietary surveys. The highest average content of nitrate was detected in rocket salad (4415 mg/kg) and radish (3817 mg/kg) and for cured meat in "Bresaola" (188 mg/kg) and in Bacon (178 mg/kg). The nitrite content was negligible both in vegetables than in cured meat. The average consumption among population resulted 3.45 g/kg bw/die and 0.62 g/kg bw/die for vegetables and cured meat respectively. The obtained data confirm that nitrate ADI was higher than the limits of 3.7 mg/kg bw/die for infants and was the highest exposure level for people of all ages. Cured meat consumption did not contribute to nitrate ADI exceedance neither as a mean nor as 99th percentile of exposure. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Ciências Sociais - Brazil is the property of Revista de Ciencias Socias do Universidade Federal do Ceara and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the case of mining machines, tribocorrosion damage is often observed. This type of consumption is caused by the joint action of mining environment factors such as abrasive and water. The search for methods to counteract tribocorrosion is of great practical importance, but it must be combined with the knowledge of methods of forecasting the value of wear. This paper presents a model of prediction of tribocorrosive wear adapted to corrodible materials - ADI containing Ni and Cu, with the strength class of 800 MPa - and results of a two-stage study on the tribocorrosive wear. Presented results indicate a distinct effect of synergy between friction and corrosion in the total wear of ADI. The tribocorrosion tests confimed the adequacy of the model developed for the ADI. [ABSTRACT FROM AUTHOR]

In this 28 day-study, we evaluated the effects of herbicide glyphosate administered by gavage to Wistar rats at daily doses equivalent to 0.1 of the acceptable operator exposure level (AOEL), 0.5 of the consumer acceptable daily intake (ADI), 1.75 (corresponding to the chronic population-adjusted dose, cPAD), and 10 mg kg-1 body weight (bw) (corresponding to 100 times the AOEL). At the end of each treatment, the body and liver weights were measured and compared with their baseline values. DNA damage in leukocytes and liver tissue was estimated with the alkaline comet assay. Oxidative stress was evaluated using a battery of endpoints to establish lipid peroxidation via thiobarbituric reactive substances (TBARS) level, level of reactive oxygen species (ROS), glutathione (GSH) level, and the activity of glutathione peroxidase (GSH-Px). Total cholinesterase activity and the activities of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) were also measured. The exposed animals gained less weight than control. Treatment resulted in significantly higher primary DNA damage in the liver cells and leukocytes. Glyphosate exposure significantly lowered TBARS in the liver of the AOEL, ADI, and cPAD groups, and in plasma in the AOEL and cPAD group. AChE was inhibited with all treatments, but the AOEL and ADI groups significantly differed from control. Total ChE and plasma/liver ROS/GSH levels did not significantly differ from control, except for the 35 % decrease in ChE in the AOEL and ADI groups and a significant drop in liver GSH in the cPAD and 100xAOEL groups. AOEL and ADI blood GSH-Px activity dropped significantly, but in the liver it significantly increased in the ADI, cPAD, and 100xAOEL groups vs. control. All these findings show that even exposure to low glyphosate levels can have serious adverse effects and points to a need to change the approach to risk assessment of low-level chronic/sub-chronic glyphosate exposure, where oxidative stress is not necessarily related to the genetic damage and AChE inhibition. [ABSTRACT FROM AUTHOR]

In this work the percent dimensional change (DC%) and its dispersion in high silicon Ductile Iron with ADI and Dual-Phase-ADI structures obtained through heat treatment starting from different as-cast microstructures, was studied. Specimens were obtained from three different melts with Si content ranging from 3.1 to 4.2%. Dual-Phase-ADI structures were obtained using special heat treatment, starting from as-cast structures. Regarding dimensional change, DC% in ADI and Dual-Phase-ADI decrease as Si% and the proportion of ferrite phase in as-cast specimens increased. On the other hand, DC% increased with austenitizing temperature and ausferrite content in the final microstructure. A fuzzy model to predict DC% in ADI parts was adapted to include DC% prediction in Dual-Phase-ADI. The fuzzy model allowed to predict the DC% for ADI and Dual-Phase-ADI parts with an root mean square <0.05%. [ABSTRACT FROM AUTHOR]

Image analysis allows to acquire a number of valuable quantitative informations on the observed structure and make appropriate conclusions. So far, a large part of analyzed images came only from light microscopes, where it was a possibility of accurately distinguish the different phases on the plane. However, the problem happened in the case of the observation of images obtained by scanning electron microscopy. In this case, the presence of various shades of gray, and the spaciousness of the image attained. To perform the analysis the matrix images of the ausferritic ductile iron were used. Full analysis was carried out using the computer program MicroMeter 1.03. Results obtained in the analysis were related directly to the results from X-ray diffraction. Obtained as a result of the analysis were related directly to the results from X-ray diffractometer. The following technique has weaknesses, including the misinterpretation by the operator microscope or program. After all, it was possible to obtain similar results to the result that has been obtained from X-ray diffractometer. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyse an innovative, cyclic heat treatment used to obtain austempered ductile iron (ADI) in laboratory conditions by means of quenching dilatometer. The relationship between the physical properties of ADI – hardness HV30 and fraction of carbon-enriched austenite V a , considered as parameters forecasting the mechanical properties of ADI – tensile strength R m and elongation A, was compared with the relationship between two basic dimensional effects revealed in differential dilatometric curves of ausferrite decomposition. The mutual compatibility between these relationships was established. Heat treatment optimization method based on the analysis of differential dilatometric curves of the ausferrite decomposition has been developed. The both approaches enabled selection of the optimal parameters of cyclic austempering and prediction of the mechanical properties which were unattainable by means of standard one-step ADI heat treatment. A kinetic analysis of decomposition after 1-step and cyclic ADI heat treatments was performed. The activation energy values for decomposition of ausferrite obtained by cyclic heat treatment 270 °C ∧∨ 390 °C and 270 °C ∧∨ 350 °C – 156 and 181 kJ/mol, respectively were found. The comparison with the activation energy for decomposition of ausferrite obtained by standard, 1-step heat treatment – 249 kJ/mol (270 °C), 230 kJ/mol (310 °C), 174 kJ/mol (350 °C) and 170 kJ/mol (390 °C) indicates that the cyclic heat treatment does not improve thermal stability of ausferrite. [ABSTRACT FROM AUTHOR]

The aim of the study was to design and optimize the complex, two-step heat treatment of Cu-Ni (Mn, Mo) ductile iron. A method for the formation and investigation of austempered ductile iron (ADI) by means of complex two-step and as comparative, standard one-step heat treatments has been developed, using quenching dilatometer. Investigations of proceeding phase transformations using differential dilatometric and DSC analysis supported by microstructural observations, hardness and austenite volume measurements have been carried out. An analysis of the temperature sequence of the ausferrite decomposition in the one-step and two-step ADI was performed, which allowed for the separation and identification of the effects responsible for the carbon-enriched austenite decomposition. A quantitative relationship was established between basic dimensional effects revealed on the differential dilatometric curve of ausferrite decomposition, which enables prognosis and optimization of the parameters of complex ADI heat treatment variants. Verification tests were performed on a stand equipped with salt furnaces enabling a quick transfer of samples from one bath to another without changing their initial temperature. Optimization of the two-step ADI heat treatment with the use of quantitative dilatometric analysis of the ausferrite decomposition, allowed to obtain for the temperature step-down heat treatment 390 °C/15, 20 min ≫ 270 °C/130 min the excellent mechanical properties, unattainable by means of standard 1-step ADI heat treatment. [ABSTRACT FROM AUTHOR]

The effects of mechanical properties and slurry erosive wear behaviour on combination of Chromium and Nickel Alloyed Ductile Iron before and after austempering process were investigated in this study. Specimens of pure ductile iron and addition of 0.16 % Cr+ 1.3 2% Ni alloyed ductile iron were produced through conventional CO2 sand casting method. The specimens were then austenitized at 900 0C before being tempered at 300 0C for 40 minutes. The slurry erosion of newly developed material were obtained by means of slurry erosive wear and the mechanical testing involved tensile test (TS 138 EN1002-1), Vickers hardness test and Charpy Impact test (ASTM E23). Roughness tests as well as SEM observations were also done to Cr-Ni alloyed ductile iron samples. All the testing was done to both as cast and austempered specimens. Austempering process heat treatment of Cr-Ni alloyed ductile iron has shown an increase in slurry wear and mechanical properties compared to as cast due to solid strengthening effect of Chromium and Nickel. Meanwhile, the austempering process does improve the hardness of alloyed ductile iron. [ABSTRACT FROM AUTHOR]

Consumer use of hemp-derived products continues to rise, underscoring the need to establish evidence-based safety guidance. The present study sought to develop recommendations for oral upper intake limits of cannabidiol (CBD) isolate. Sufficiently robust and reliable data for this purpose were identified from published human clinical trials and guideline-compliant toxicity studies in animal models. Based on the metrics used in this assessment, a potential Acceptable Daily Intake (ADI) value of 0.43 mg/kg-bw/d (e.g., 30 mg/d for 70-kg adult) was determined for the general population based on liver effects in human studies. This value applies to the most sensitive subpopulations, including children, over a lifetime of exposure and from all sources, including food. For dietary supplements with adequate product labeling intended for use by healthy adults only, a potential Upper Intake Limit (UL) of 70 mg/d was determined based on reproductive effects in animals. For healthy adults, except those trying to conceive, or currently pregnant or lactating, a conservative dietary supplement UL of 100 mg/d was identified based on liver effects; however, as the target population excludes individuals at risk for liver injury, an alternative dietary supplement UL of 160 mg/d for this population can also be considered. • Potential Acceptable Daily Intake value of 0.43 mg/kg-bw/d was derived for the general population. • ADI applies to sensitive subpopulations, including children, and from all sources, including food. • Upper Intake Limit (UL) of 70 mg/d was developed for dietary supplement use by all healthy adults. • ULs of 100 and 160 mg/d derived for healthy adults not trying to conceive, pregnant, or lactating. • Recommendations are based solely on the authors' assessments and are not regulatory guidelines. [ABSTRACT FROM AUTHOR]

The article presents opportunities offered by the data mining analysis as applied to studies of the effect of process parameters on the mechanical properties of ADI. The applied methods of regression trees and cluster analysis allow for the detection of relationships between parameters and also allow determination of strength and form of the impact of different factors. The results of this study allow the creation of knowledge bases for systems supporting the decision-making process in technology.

Technical standards are important documents for the development, application and expansion of any engineering material. In the casting industry, technical standards are the premise for producing high quality castings and they provide tools for inspection and acceptance of castings, and aid both the purchaser and the producer. In this paper, the most recent worldwide and Chinese technical standards for SG iron, ADI, CGI and heat resisting iron castings are described. It can be seen that these Chinese national standards have reached the level of world-class standards. This will be beneficial for enhancing the Chinese foundry industry, improving Chinese casting quality and aid the supply of good quality castings to China’s own industry. It is also good for the international buyer to source castings in China, and for the Chinese casting producer to export castings to other parts of the world. Current development trends for cast irons are also discussed.

The paper discusses possible applications of the percolation theory in analysis of the microstructure images of polycrystalline materials. Until now, practical use of this theory in metallographic studies has been an almost unprecedented practice. Observation of structures so intricate with the help of this tool is far from the current field of its application. Due to the complexity of the problem itself, modern computer programmes related with the image processing and analysis have been used. To enable practical implementation of the task previously established, an original software has been created. Based on cluster analysis, it is used for the determination of percolation phenomena in the examined materials. For comparative testing, two two-phase materials composed of phases of the same type (ADI matrix and duplex stainless steel) were chosen. Both materials have an austenitic - ferritic structure. The result of metallographic image analysis using a proprietary PERKOLACJA.EXE computer programme was the determination of the content of individual phases within the examined area and of the number of clusters formed by these phases. The outcome of the study is statistical information, which explains and helps in better understanding of the planar images and real spatial arrangement of the examined material structure. The results obtained are expected to assist future determination of the effect that the internal structure of two-phase materials may have on a relationship between the spatial structure and mechanical properties.

Neuroanatomical differences in the cerebellum are among the most consistent findings in autism spectrum disorder (ASD), but little is known about the relationship between cerebellar dysfunction and core ASD symptoms. The newly-emerging existence of cerebellar sensorimotor and cognitive subregions provides a new framework for interpreting the functional significance of cerebellar findings in ASD. Here we use two complementary analyses — whole-brain voxel-based morphometry (VBM) and the SUIT cerebellar atlas — to investigate cerebellar regional gray matter (GM) and volumetric lobular measurements in 35 children with ASD and 35 typically-developing (TD) children (mean age 10.4 ± 1.6 years; range 8–13 years). To examine the relationships between cerebellar structure and core ASD symptoms, correlations were calculated between scores on the Autism Diagnostic Observation Schedule (ADOS) and Autism Diagnostic Interview (ADI) and the VBM and volumetric data. Both VBM and the SUIT analyses revealed reduced GM in ASD children in cerebellar lobule VII (Crus I/II). The degree of regional and lobular gray matter reductions in different cerebellar subregions correlated with the severity of symptoms in social interaction, communication, and repetitive behaviors. Structural differences and behavioral correlations converged on right cerebellar Crus I/II, a region which shows structural and functional connectivity with fronto-parietal and default mode networks. These results emphasize the importance of the location within the cerebellum to the potential functional impact of structural differences in ASD, and suggest that GM differences in cerebellar right Crus I/II are associated with the core ASD profile.

Abstract Following a request from the European Commission to EFSA, the EFSA Scientific Committee (SC) prepared a guidance for the risk assessment of substances present in food intended for infants below 16 weeks of age. In its approach to develop this guidance, the EFSA SC took into account, among others, (i) an exposure assessment based on infant formula as the only source of nutrition; (ii) knowledge of organ development in human infants, including the development of the gut, metabolic and excretory capacities, the brain and brain barriers, the immune system, the endocrine and reproductive systems; (iii) the overall toxicological profile of the substance identified through the standard toxicological tests, including critical effects; (iv) the relevance for the human infant of the neonatal experimental animal models used. The EFSA SC notes that during the period from birth up to 16 weeks, infants are expected to be exclusively fed on breast milk and/or infant formula. The EFSA SC views this period as the time where health‐based guidance values for the general population do not apply without further considerations. High infant formula consumption per body weight is derived from 95th percentile consumption. The first weeks of life is the time of the highest relative consumption on a body weight basis. Therefore, when performing an exposure assessment, the EFSA SC proposes to use the high consumption value of 260 mL/kg bw per day. A decision tree approach is proposed that enables a risk assessment of substances present in food intended for infants below 16 weeks of age. The additional information needed when testing substances present in food for infants below 16 weeks of age and the approach to be taken for the risk assessment are on a case‐by‐case basis, depending on whether the substance is added intentionally to food and is systemically available.