Foreword: Special issue Mycotoxins in Latin America

Latin America with its considerable North-South extent is subject to climate that varies from tropical, subtropical and warm temperate to temperate. Different agricultural products are produced in the area including cereals, oilseeds, beans, fruits and nuts together with animal production including cattle for beef and milk, pigs, poultry and fish. The heterogeneity of agriculture in Latin America is reflected in the diversity of the region's farm structures. While agriculture in the Southern Cone is dominated by large, commercial and export-oriented farms, particularly in Argentina and Brazil, besides increasingly in other countries like Uruguay, much of the rest of the region is characterised by smallholder and family agriculture. The contamination of agricultural products with mycotoxins has impact both human and animal health, as well as the economy due to losses related to rejections of agricultural products and by-products during trade. The economic burden related to the consumption of mycotoxins by animals is especially important, causing productivity losses up to the death of animals. The relevant mycotoxins are fumonisins, deoxynivalenol (DON) and zearalenone (ZEN) in cereals and cereal-based products, aflatoxins in cereals, oily seeds and nuts, aflatoxin M1 in milk and dairy products as well as ochratoxin A (OTA) in coffee, grapes and raisins. Co-occurrence of mycotoxins has also been observed mainly with aflatoxins and fumonisins in different Latin American countries (Torres et al., 2015). Advances on legislation in different countries including Argentina, Brazil, Chile, Mexico and Uruguay have been done to establish maximum limits for mycotoxins including aflatoxins, DON, ZEN, OTA, patulin and ergot alkaloids (ANVISA, 2011/2017; CAA, 2019/2021, Norma Oficial Mexicana, N.-243-S., 2010/2010; Reglamento Sanitario de los Alimentos, 2013).Fil: Chulze, Sofia Noemi. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigación en Micología y Micotoxicología. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación en Micología y Micotoxicología; ArgentinaFil: Torres, Adriana Mabel. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigación en Micología y Micotoxicología. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación en Micología y Micotoxicología; ArgentinaFil: Torres, Olga. Laboratorio Diagnóstico Molecular; GuatemalaFil: Mallmann, Carlos Alberto. Universidade Federal de Santa Maria; Brasi

Specific heat and nonlinear susceptibility in spin glasses with random fields

We study magnetic properties of spin glass (SG) systems under a random field (RF), based on the suggestion that RFs can be induced by a weak transverse field in the compound LiHo x Y 1 − x F 4 .Weconsideracluster spin model that allows long-range disordered interactions among clusters and short-range interactions inside the clusters, besides a local RF for each spin following a Gaussian distribution with standard deviation Δ. We adopt the one-step replica symmetry breaking approach to get an exactly solvable single-cluster problem. We discuss the behavior of order parameters, specific heat C m , nonlinear susceptibility χ 3 , and phase diagrams for different disorder configurations. In the absence of RF, the χ 3 exhibits a divergence at T f , while the C m shows a broad maximum at a temperature T** around 30% above T f , as expected for conventional SG systems. The presence of RF changes this scenario. The C m still shows the maximum at T** that is weakly dependent on Δ. However,the T f is displaced to lower temperatures, enhancing considerably the ratio T** /T f . Furthermore, the divergence in χ 3 is replaced by a rounded maximum at a temperature T*, which becomes increasingly higher than T f as Δ is enhanced. As a consequence, the paramagnetic phase is unfolded in three regions: (i) a conventional paramagnetism ( T>T** ); (ii) a region with formation of short-range order with frozen spins ( T*<T <T** ); (iii) a region with slow growth of free-energy barriers slowing down the spin dynamics before the SG transition ( T f <T <T* ) suggesting an intermediate Griffiths phase before the SG state. Our results reproduce qualitatively some findings of LiHo x Y 1 − x F 4 as the rounded maximum of χ 3 behavior triggered by RF and the deviation of the conventional relationship between the T f and T**

Nonlinear susceptibility of a quantum spin glass under uniform transverse and random longitudinal magnetic fields

The interplay between quantum fluctuations and disorder is investigated in a quantum spin-glass model, in the presence of a uniform transverse field , as well as of a longitudinal random field hi , which follows a Gaussian distribution characterized by a width proportional to . The interactions are infinite-ranged, and the model is studied through the replica formalism, within a one-step replica-symmetry-breaking procedure; in addition, the dependence of the Almeida-Thouless eigenvalue λAT (replicon) on the applied fields is analyzed. This study is motivated by experimental investigations on the LiHoxY1−xF4 compound, where the application of a transverse magnetic field yields rather intriguing effects, particularly related to the behavior of the nonlinear magnetic susceptibility χ3, which have led to a considerable experimental and theoretical debate. We have analyzed two physically distinct situations, namely, and considered as independent, as well as these two quantities related, as proposed recently by some authors. In both cases, a spin-glass phase transition is found at a temperature Tf , with such phase being characterized by a nontrivial ergodicity breaking; moreover, Tf decreases by increasing towards a quantum critical point at zero temperature. The situationwhere and are related [ ≡ ( )] appears to reproduce better the experimental observations on the LiHoxY1−xF4 compound, with the theoretical results coinciding qualitatively with measurements of the nonlinear susceptibility χ3 In this later case, by increasing gradually, χ3 becomes progressively rounded, presenting a maximum at a temperature T ∗ (T ∗ > Tf ), with both the amplitude of the maximum and the value of T ∗ decreasing gradually. Moreover, we also show that the random field is the main responsible for the smearing of the nonlinear susceptibility, acting significantly inside the paramagnetic phase, leading to two regimes delimited by the temperature T ∗, one for Tf T ∗. It is argued that the conventional paramagnetic state corresponds to T >T ∗, whereas the temperature region Tf < T < T ∗ may be characterized by a rather unusual dynamics, possibly including Griffiths singularities

Nonlinear susceptibility of a quantum spin glass under uniform transverse and random longitudinal magnetic fields

The interplay between quantum fluctuations and disorder is investigated in a quantum spin-glass model, in the presence of a uniform transverse field , as well as of a longitudinal random field hi , which follows a Gaussian distribution characterized by a width proportional to . The interactions are infinite-ranged, and the model is studied through the replica formalism, within a one-step replica-symmetry-breaking procedure; in addition, the dependence of the Almeida-Thouless eigenvalue λAT (replicon) on the applied fields is analyzed. This study is motivated by experimental investigations on the LiHoxY1−xF4 compound, where the application of a transverse magnetic field yields rather intriguing effects, particularly related to the behavior of the nonlinear magnetic susceptibility χ3, which have led to a considerable experimental and theoretical debate. We have analyzed two physically distinct situations, namely, and considered as independent, as well as these two quantities related, as proposed recently by some authors. In both cases, a spin-glass phase transition is found at a temperature Tf , with such phase being characterized by a nontrivial ergodicity breaking; moreover, Tf decreases by increasing towards a quantum critical point at zero temperature. The situationwhere and are related [ ≡ ( )] appears to reproduce better the experimental observations on the LiHoxY1−xF4 compound, with the theoretical results coinciding qualitatively with measurements of the nonlinear susceptibility χ3 In this later case, by increasing gradually, χ3 becomes progressively rounded, presenting a maximum at a temperature T ∗ (T ∗ > Tf ), with both the amplitude of the maximum and the value of T ∗ decreasing gradually. Moreover, we also show that the random field is the main responsible for the smearing of the nonlinear susceptibility, acting significantly inside the paramagnetic phase, leading to two regimes delimited by the temperature T ∗, one for Tf T ∗. It is argued that the conventional paramagnetic state corresponds to T >T ∗, whereas the temperature region Tf < T < T ∗ may be characterized by a rather unusual dynamics, possibly including Griffiths singularities

Fibrinas ricas em plaquetas, uma alternativa para regeneração tecidual: revisão de literatura

Objetivo: o potencial de cicatrização dos fatores de crescimento plaquetários tem gerado interesse no uso de Fibrina rica em plaquetas (PRF) que pertence a uma nova geração de concentrados de plaquetas. A membrana de Fibrina Rica em Plaquetas promove uma favorável arquitetura fisiológica para apoiar o processo de cicatrização. O objetivo desse trabalho foi fazer uma revisão de literatura sobre fibrinas ricas em plaquetas na regeneração óssea, evidenciar suas indicações e buscar evidências de benefícios na formação óssea. Metodologia: para isso, foi realizado um levantamento bibliográfico dos artigos publicados entre 1985 e 2013. O termo utilizado foi fibrina rica em plaquetas. Vinte e um artigos foram selecionados, os quais relataram a performance de cicatrização e regeneração óssea pela fibrina rica em plaquetas na Implantodontia. Resultados: nos estudos pôde-se observar que o PRF parece gerar uma rede de fibrina semelhante ao natural, desencadeando uma maior proliferação celular e, consequentemente, regeneração óssea. Conclusão: diante disso, as fibrinas ricas em plaquetas têm demonstrado potencial para auxiliar na regeneração tecidual. A literatura mostra que este biomaterial é favorável para o desenvolvimento de uma matriz de cicatrização coerente sem excessos inflamatórios. É uma terapia promissora, que no entanto necessita de mais estudos clínicos longitudinais de acompanhamento

Digestibility and metabolism of piglet diets containing zearalenone with addition of organoaluminosilicate

Um experimento foi realizado para avaliar a digestibilidade de dietas e balanços metabólicos de suínos alimentados com dietas contendo zearalenona (ZEA) com e sem adição de organoaluminossilicato (OA). Foram utilizadas 12 leitoas com peso inicial de 12 kg, alojadas em gaiolas metabólicas. O delineamento foi inteiramente casualizado, com três tratamentos (controle, controle + 2 ppm de ZEA e controle + 2 ppm de ZEA com adição de 0,3% de OA na dieta) e quatro repetições, com o animal como unidade experimental. A ZEA e o OA não influenciaram (p > 0,05) o consumo de matéria seca, a digestibilidade da matéria seca e energia bruta, metabolização da energia, proteína digestível e energias digestível e metabolizável das dietas. A ZEA e OA não alteraram o balanço do N (p > 0,05), mas modificaram (p 0,05) a absorção de P em função da ingestão. O consumo de 2 ppm de ZEA com ou sem adição de 0,3% de OA não interfere na digestibilidade das dietas e no metabolismo dos suínos.An experiment was carried out to asses diet digestibility and metabolism balance of piglets fed on diets containing zearalenone (ZEA) with and without addition of organaluminisilicate (OA). Twelve gilts littermates were used, with 12 kg initial body weight, housed in metabolic cages. A completely randomized design was used and comprised three treatments (control, control + 2 ppm ZEA, and control + 2 ppm ZEA with addition of 0.3% of OA), and four replications, being the animal as experimental unit. The ZEA and the OA did not affect (p>0.05) dry matter intake, digestibility of dry matter and gross energy, metabolizable energy, digestible energy as well as digestible protein. The nitrogen balance was not modified (p > 0.05) by ZEA and OA. However, it influenced (p 0.05) the absorption of P in relation to the ingestion. The intake of 2 ppm of ZEA with or without addition of 0.3% of OA in diet does not affect the digestibility of diets and the metabolism of pigs

Soil tillage to reduce surface metal contamination – model development and simulations of zinc and copper concentration profiles in a pig slurry-amended soil

Long-term applications of organic amendments, such as pig slurry (PS), may represent environmental risk of soil and water pollution by trace metals (TM). Our objective was to examine different soil and manure management scenarios that enhance the long-term agricultural use of soils under repetitive PS applications while avoiding environmental risk. Firstly, we developed a new module for simulating the impacts of soil tillage frequencies in Hydrus-1D. Secondly, we used a previously validated modeling approach to predict the surface accumulation and movement of the TM during the next 100-year in the soil under different PS doses (80 and 40m3ha-1cultivation-1) and tillage frequencies (no-tillage and 20, 10, and 5-year tillage). No-tillage simulations revealed consistent TM surface accumulations, reaching the soil threshold value for Cu in the 0-20cm layer after 86 years of PS amendments at high doses, but in layers 0-5, 0-10, and 5-10cm, this concentration was already reached after 17, 38, and 75 years, respectively. While soil tillage reduced TM concentrations over the top 20cm of the soil profile, it increased their transfer to deeper layers. Periodical soil tillage each 5, 10, and 20 years was found to allow PS applications without reaching the Cu threshold value in soil during 100 years. However, soil solution concentrations of Zn reached the threshold values for groundwater. Therefore, the best manure management practice for the long-term PS disposal with respect to Zn and Cu concentrations in soil is the application of moderate PS rates. © 2014 Elsevier B.V

Central Pathology Review in SENTIX, a Prospective Observational International Study on Sentinel Lymph Node Biopsy in Patients with Early-Stage Cervical Cancer (ENGOT-CX2)

The quality of pathological assessment is crucial for the safety of patients with cervical cancer if pelvic lymph node dissection is to be replaced by sentinel lymph node (SLN) biopsy. Central pathology review of SLN pathological ultrastaging was conducted in the prospective SENTIX/European Network of Gynaecological Oncological Trial (ENGOT)-CX2 study. All specimens from at least two patients per site were submitted for the central review. For cases with major or critical deviations, the sites were requested to submit all samples from all additional patients for second-round assessment. From the group of 300 patients, samples from 83 cases from 37 sites were reviewed in the first round. Minor, major, critical, and no deviations were identified in 28%, 19%, 14%, and 39% of cases, respectively. Samples from 26 patients were submitted for the second-round review, with only two major deviations found. In conclusion, a high rate of major or critical deviations was identified in the first round of the central pathology review (28% of samples). This reflects a substantial heterogeneity in current practice, despite trial protocol requirements. The importance of the central review conducted prospectively at the early phase of the trial is demonstrated by a substantial improvement of SLN ultrastaging quality in the second-round review