Task-Specific Ionic Liquids and Deep Eutectic Solvents for Lubrication Technology

It is estimated that around 23% of the world’s total energy consumption comes from tribological contacts, namely due to energy losses during the mechanical movements, which accentuated the need for more efficient lubrication. Lubricants have been used to lower friction and wear by separating the surfaces sliding in relative motion, increasing the energy efficiency and lifetime of mechanical components. It is of extreme importance that the used lubricants comply with the need for higher sustainability and, with that in mind, researchers all over the world are continuously in the search for new and improved ways of reducing friction and wear. Ionic Liquids (ILs) are organic salts with low melting point (generally lower than 100 °C) that have attracted the research community due to their very interesting properties such as high chemical and thermal stability, high ionic conductivity, non-flammability, ease in dissolving organic, inorganic and polymeric materials and their tunability towards several applications through the combination of different cations and anions. Besides that, they have very low vapor pressures which makes them environmentally friendly materials. Ionic Liquids often have good performance in friction and wear reduction, by enhancing the tribofilm formation between different tribopairs, making them very promising alternative lubricants. However, they are very expensive to be used as pure lubricants. Viable alternatives are the use of ionic liquids as additives to a base oil or the use of Deep Eutectic Solvents (DESs), which are mixtures possessing a significant decrease on the melting temperature comparing to the original individual components. DESs have similar properties to ILs but can be less toxic, cheaper and easier to prepare, which makes them very interesting and promising lubricant candidates. In this thesis, the use of different ionic liquids as additives and deep eutectic solvents as lubricants is proposed, with the goal of reducing friction and wear between moving parts, towards a more sustainable world. The most promising fluids can be applied in Nano and Micro electromechanical devices (NEMS/MEMS) which are made of silicon, and also in bearings of steel, which is one of the main materials used in industry.Estima-se que ~23% da energia total consumida no mundo provem de contactos tribológicos, nomeadamente devido a perdas de energia durante movimentos mecânicos, o que acentua a necessidade de uma lubrificação mais eficiente. Os lubrificantes têm vindo a ser utilizados para reduzir o atrito e desgaste através da separação das superfícies deslizantes em movimento relativo, aumentando a eficiência energética e o tempo de vida dos componentes mecânicos. É de extrema importância que o uso de lubrificantes cumpra os critérios de uma maior sustentabilidade e, com isso em mente, os investigadores estão continuamente à procura de formas novas e melhoradas de reduzir o atrito e desgaste. Os Líquidos Iónicos são sais orgânicos com baixo ponto de fusão (geralmente abaixo de 100 °C) que têm vindo a atrair a atenção da comunidade científica devido às suas propriedades interessantes tais como elevada estabilidade química e térmica, elevada condutividade iónica, não inflamabilidade, facilidade em dissolver materiais orgânicos, inorgânicos e poliméricos e a sua capacidade de adequação para diferentes aplicações através da combinação de catiões e aniões diferentes. Além disso, apresentam uma pressão de vapor muito baixa, o que os torna materiais amigos do ambiente. Os líquidos iónicos têm frequentemente bom desempenho em termos de redução de atrito e desgaste, originando a formação de tribofilmes entre diferentes tribopares, o que os torna lubrificantes alternativos muito promissores. No entanto, o seu preço é demasiado alto para serem utilizados como lubrificantes puros. Algumas alternativas viáveis são o uso de líquidos iónicos como aditivos a um óleo base ou o uso de Solventes Eutéticos Profundos (em inglês Deep Eutectic Solvents, DESs), que são misturas cuja temperatura de fusão é muito menor do que as dos componentes individuais que lhes deram origem. Os DESs apresentam propriedades semelhantes às dos líquidos iónicos mas são menos tóxicos, mais baratos e mais fáceis de preparar, o que os torna muito interessantes como lubrificantes. Nesta tese, propõe-se a utilização de diferentes líquidos iónicos como aditivos e solventes eutéticos profundos como lubrificantes, com o objetivo de diminuir o atrito e desgaste entre superfícies com partes móveis, tendo em vista um mundo mais sustentável. Os fluídos mais promissores poderão ser utilizados em dispositivos Nano e Micro eletromecânicos (NEMS/MEMS) que são constituídos por silício, e também em rolamentos de aço, que é um dos principais materiais utilizados na indústria

Stages for Undertaking a Systematic Review

Tem-se verificado crescente aumento do uso da revisão sistemática como metodologia de investigação para compilar e analisar grandes conjuntos de dados de estudos existentes. Com este aumento também aumentaram as recomendações para conduzir este tipo de investigação. O objectivo deste artigo é fornecer um guia para compreender e/ou realizar uma revisão sistemática para publicação, indicando todas as etapas do processo de revisão. Ao fazerem uma revisão sistemática da literatura, os autores tornam-se conhecedores do tema e, embora consuma muito tempo, podem desenvolver um conjunto de competências incluindo a de pesquisa da literatura e de redacção científica. A revisão sistemática, comparada com a investigação primária, requer relativamente poucos recursos, permitindo que os clínicos normalmente não envolvidos em investigação produzam artigos clinicamente relevantes e de alta qualidade

Estudo de entalpias de sublimação em compostos organometálicos

Tese de mestrado, Química (Química) Universidade de Lisboa, Faculdade de Ciências, 2017A validação de potenciais intermoleculares (campos de força) capazes de modelar convenientemente interações entre moléculas é de extrema importância para a interpretação das propriedades macroscópicas de um sistema recorrendo a métodos teóricos, tais como simulações por Dinâmica Molecular. Na literatura podem ser encontradas diversas parametrizações adequadas utilizadas, por exemplo, em compostos orgânicos. No entanto, este tipo de dados é escasso para moléculas contendo metais de transição e, para além disso, de uma forma geral, os valores disponíveis não correspondem a determinações sistemáticas e consistentes. Um dos procedimentos mais promissores para a validação de campos de força envolve a comparação de dados energéticos e volumétricos, como entalpias de sublimação e volumes de células unitárias de estruturas cristalinas, obtidos experimentalmente, com os previstos por modelos teóricos. Este tipo de parâmetros pode ser encontrado na literatura para, por exemplo, compostos organometálicos. No entanto, verifica-se que, de uma forma geral, a forma cristalina à qual se referem os valores de entalpias de sublimação experimentais é desconhecida, inviabilizando a sua utilização neste tipo de procedimentos. Neste contexto, o principal objetivo desta tese foi a determinação de entalpias de sublimação para compostos organometálicos com estrutura cristalina conhecida, para posterior utilização de referência no estabelecimento de potenciais intermoleculares para este tipo de substâncias. Foram selecionados vários compostos contendo metais das três séries de transição: metiltrioxorénio (VII) (CH3O3Re), decacarbonilo de di-rénio (C10O10Re2), acetilacetonato de ferro (III) (C15H21O6Fe), acetilacetonato de platina (II) (C10H14O4Pt), tetrametil heptanodionato de zinco (II) (C22H38O4Zn), acetilacetonato de zircónio (IV) (C20H28O8Zr), acetilacetonato de níquel (II) (C10H14O4Ni), acetilacetonato de cobre (II) (C10H14O4Cu), acetilacetonato de háfnio (IV) (C20H28O8Hf), acetilacetonato de cobalto (II) (C10H14O4Co) e metóxido de tântalo (V) (C5H15O5Ta). A escolha destas substâncias foi realizada com base nos seguintes critérios: i) são substâncias acessíveis comercialmente; ii) a maioria pertence a famílias quimicamente semelhantes; iii) têm estruturas cristalinas conhecidas; iv) quando existem, os valores de entalpias de sublimação publicados não estão associadas a qualquer estrutura cristalina conhecida e, em muitos casos, apresentam discrepâncias consideráveis entre si. De forma a cumprir o objetivo mencionado, as amostras foram purificadas por sublimação e, posteriormente, caracterizadas em termos de pureza química por análise elementar, espectroscopia de infravermelho de refletância difusa com transformada de Fourier (DRIFT), ressonância magnética nuclear de protão (1H-RMN) e de carbono (13C-RMN) e calorimetria diferencial de varrimento (DSC). Em termos de pureza de fase, foram realizados estudos de difração de raios-X de cristal único e de pós e calorimetria diferencial de varrimento. Os estudos de DSC permitiram verificar se ocorriam transições de fase sólido-sólido que era necessário ter em conta na determinação de entalpias de sublimação e na sua atribuição a uma fase cristalina específica. Após caracterização das amostras, foram determinadas as respetivas entalpias de sublimação padrão, ∆sub H0m , a uma dada temperatura por microcalorimetria Calvet. A correção dos valores de ∆ subH0m da temperatura de trabalho para 298,15 K foi efetuada com recurso às capacidades caloríficas determinadas por DSC e por métodos de termodinâmica estatística. A exatidão do procedimento usado para determinar as entalpias de sublimação foi verificada comparando os resultados obtidos para o ácido benzóico com valores existentes na literatura. Os valores de entalpia de sublimação para os compostos a 298,15 K foram: ∆subH0m (CH3O3Re) = 70,2±0,4 kJ·mol-1, ∆subH0m (C10O10Re2) = 97,4±0,9 kJ·mol-1, ∆subH0m (C15H21O6Fe) = 140,3±3,7 kJ·mol-1, ∆subH0m (C10H14O4Pt) = 123,6±0,9 kJ·mol-1 e o sub m (C22H38O4Zn) = 117,9±0,3 kJ·mol-1. Verificou-se que as restantes substâncias se decompunham durante o processo de sublimação, inviabilizando a determinação. Este resultado sugere que as discrepâncias entre os valores de ∆subH0m reportados na literatura para estes compostos podem ter origem em problemas de decomposição não reportados. Este facto reforça a ideia de que a escolha de entalpias de sublimação publicadas na validação e desenvolvimento de campos de força deve ser realizada com extremo cuidado.The validation of intermolecular potentials (force fields) capable of conveniently modeling interactions between molecules is of extreme importance on the interpretation of the macroscopic properties of a system using theoretical methods, such as Molecular Dynamics simulations. On the literature several parameterizations can be found for organic compounds. However, this type of data is scare for molecules containing transition metals and, besides, generally speaking, most of them do not correspond to systematic and consistent determinations. One of the most promising methods for the validation of force fields involves the comparison of energetic and volumetric data, such as the enthalpy of sublimation and unitary cell volumes of crystalline structures, experimentally obtained, with the ones predicted by theoretical models. This type of parameters can be found on the literature for, for example, organometallic compounds. However, it appears that, in a general way, the crystalline structure to which the experimental values of enthalpies of sublimation refer to is unknown, which makes it impossible to use them in this type of procedure. In this context, the main objective of this thesis was the determination of enthalpies of sublimation for organometallic compounds with a known crystalline structure, for later reference use in the establishment of intermolecular potentials for this type of compounds. Several compounds containing metals from the three transition series were selected: methyltrioxorhenium (VII) (CH3O3Re) decacarbonyl dirhenium (C10O10Re2), iron (III) acetylacetonate (C15H21O6Fe), platinum (II) acetylacetonate (C10H14O4Pt), zinc (II) tetrametyl heptanodionate (C22H38O4Zn), zirconium (IV) acetylacetonate (C20H28O8Zr), niquel (II) acetylacetonate (C10H14O4Ni), copper (II) acetylacetonate (C10H14O4Cu), hafnium (IV) acetylacetonate (C20H28O8Hf), cobalt (II) acetylacetonate (C10H14O4Co) and tantalum (V) methoxide (C5H15O5Ta). The choice of these substances was based on the following criteria: i) they are commercially available substances; ii) most of them belong to chemically similar families; iii) they have known crystal structures; iv) they have several values of enthalpies of sublimation on the literature that, besides not being associated to known crystalline structures, in most cases, present considerable discrepancies among them. In order to fulfil the mentioned objective, the samples were purified by sublimation and, then, characterized in terms of chemical purity by elemental analysis, diffuse reflectance infrared Fourier transform (DRIFT), proton and carbon nuclear magnetic resonance (1H-NMR and 13C-NMR) and differential scanning calorimetry (DSC). In terms of phase purity, single crystal X-ray diffraction, powder X-ray diffraction and DSC studies were carried out. The DSC studies allowed to verify the existence of solid-solid phase transitions that needed to be taken into account on the determination of enthalpies of sublimation and in its assignment to a specific crystalline phase. After the samples were characterized, the respective enthalpies of sublimation,∆subH0m , were determined at a given temperature by Calvet microcalorimetry. The correction of the values of ∆subH0m from the work temperature to 298.15 K was done with the heat capacities determined by DSC and by statistical thermodynamics methods. The accuracy of the procedure used to determine the enthalpy of sublimation was verified by comparing the obtained results for benzoic acid with values from the literature. The values of enthalpies of sublimation for the compounds at 298.15 K were: ∆subH0m (CH3O3Re) = 70.2±0.4 kJ·mol-1,∆subH0m (C10O10Re2) = 97.4±0.9 kJ·mol-1,∆subH0m (C15H21O6Fe) = 140.3±3.7 kJ·mol-1, ∆subH0m (C10H14O4Pt) = 123.6±0.9 kJ·mol-1 and o ∆subH0m (C22H38O4Zn) = 117.9±0.3 kJ·mol-1. For the other studied substances we verified decomposition problems during the sublimation process, making the determination impossible. This result indicated that the discrepancies between the values of ∆subH0m reported on the literature for these compounds can be caused by decomposition problems, which were not reported. This fact enhances the idea that the choice of enthalpies of sublimation published for the validation and development of force fields must be done extremely carefully

New Protic Ionic Liquids as Potential Additives to Lubricate Si-Based MEMS/NEMS

Funding Information: The work was financed by the Portuguese Foundation for Science and Technology (FCT) through the projects UIDB/00100/2020, UIDP/00100/2020 and IMS-LA/P/0056/2020 and through the PhD grant SFRH/BD/140079/2018 from Mariana Donato. Additionally, this work was financed by national funds from FCT in the scope of the projects UIDB/50022/2020 (IDMEC/LAETA) and LA/P/0037/2020, UIDP/50025/2020 and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling and Nanofabrication—i3N. Publisher Copyright: © 2023 by the authors.The motivation for this work was to develop new protic ionic liquids (PILs) as additives for the lubrication of micro and nanoelectromechanical systems (MEMS and NEMS). Ten PILs based on the combination of methylimidazolium ([MIMH]), 4-picolinium ([4-picH]), pyridinium ([PyrH]), 1,8-diazabicyclo[5.4.0]-undec-7-ene-8-ium ([DBUH]) and tetramethylguanidinium ([TMGH]) cations with hydrogen sulfate([HSO4]) and mesylate ([MeSO3]) anions were tested as additives in polyethylene glycol (PEG200) to lubricate steel/silicon and silicon/silicon contacts. The best additive was [4-picH][HSO4], which adsorbed strongly on the Si surface, leading to a protective film that reduced wear by up to 15 times compared to PEG200.publishersversionpublishe

Relationship in the anatomical position of the greater palatine hole in patients with superior premolar exodonctic and orthodontic treatment

Antecedentes: la determinación de la relación entre el agujero palatino mayor (APM), la raíz distal del segundo molar y la sutura media palatina (SMP) permitirá en la población, generar el conocimiento necesario para poder realizar una planificación adecuada de los procedimientos quirúrgicos que involucren esta zona, disminuyendo así la tasa de iatrogenia y las complicaciones intra y posquirúrgicas en esta región anatómica, favoreciendo la toma de mayor cantidad de injerto del paladar. Objetivo: determinar la relación de la posición anatómica del agujero palatino mayor en pacientes con exodoncia de premolares superiores indicados por ortodoncia con tratamiento ortodóntico finalizado comparándolo con pacientes sin exodoncia de premolares y sin tratamiento ortodóntico, mediante tomografías computarizadas de haz de cono. Materiales y métodos: se incluyeron imágenes CBCT de 63 pacientes en este estudio, las cuales se dividieron en dos grupos; el grupo 1 incluyó 33 CBCT de pacientes con exodoncia de premolares y tratamiento ortodóntico finalizado, y el grupo 2 incluyó 30 CBCT de pacientes sin exodoncia de premolares ni tratamiento ortodóntico. Se analizaron las tomografías con el programa CS 3D Imaging Software tomando dos mediciones: a) raíz distal del segundo molar superior y b) sutura media palatina con respecto al agujero palatino mayor. Resultados: la edad promedio de los pacientes del grupo 1 fue de 30,76 y del grupo 2 fue de 44,2; predominó el sexo femenino en ambos grupos. En el grupo 1 la distancia del APM a la SMP del lado derecho fue de 14,16±0,80 mm y del lado izquierdo de 14,28±0,96 mm; respecto a la referencia anatómica de la raíz distal del segundo molar, del lado derecho fue 10,04±2,19 mm y del izquierdo de 10,40±2,53 mm. En el grupo 2 la distancia del APM a la SMP del lado derecho fue de 13,59±2,96 mm y del lado izquierdo de 14,32±1,04 mm. Respecto a la referencia anatómica de la raíz distal del segundo molar, del lado derecho fue 8,15±3,18 mm y del izquierdo de 8,14±3,83 mm en pacientes con exodoncia de premolares y tratamiento de ortodoncia finalizado. La referencia del agujero palatino mayor con respecto a la sutura media palatina, no varió en los pacientes sin exodoncia de premolares ni tratamiento de ortodoncia; mientras que en relación con la raíz distal del segundo molar si se presentó diferencia estadísticamente significativa entre la media de la distancia del APM a la raíz distal del segundo molar en el lado derecho del grupo 1 (M=10,04 DE=2,19) y la media de la distancia del APM a la raíz distal del segundo molar derecho del grupo 2 (M=8,15 DE=3,18) p<0,05. De igual manera, hubo una diferencia estadísticamente significativa entre la distancia del APM a la raíz distal segundo molar izquierdo en el grupo 1 (Me=10 RI=2) y el grupo 2 (Me=7,60 RI=6,1) p <0,05. Conclusión: es importante considerar las tomografías, como ayuda diagnóstica, para el estudio de estructuras anatómicas que a través de otras modalidades de imagen no pueden ser vistas. En procedimientos que requieran una toma extensa de injerto de tejido blando del paladar, el agujero palatino mayor puede ser un obstáculo anatómico, que con el uso de la tomografía puede proporcionarle al clínico una cirugía más segura. El presente estudio mostró una diferencia estadísticamente significativa con respecto a la distancia del APM a la raíz distal del segundo molar, del lado izquierdo y derecho, en pacientes con exodoncia de premolares y tratamiento ortodóntico finalizado.Facultad de Odontología, Pontificia Universidad JaverianaBackground: the determination of the relation between the greater palatine foramen, the distal root of the second upper molar and the middle maxillary suture will allow the population the necessary knowledge to be able to carry out an adequate planning of the surgical procedures that involve this area, thus decreasing the iatrogenic rate and intra and post-surgical complications in this anatomical region, favoring the taking of greater amount of palate graft. Objective: determine the relation of the anatomical position of the greater palatine foramen in patients with exodontic of upper premolar indicated by orthodontics with finished orthodontic treatment by comparing it with patients without premolar orthodontics and without orthodontic treatment, using cone beam computed tomography (CBCT). Materials and methods: CBCT images of 63 patients were included in this study, which were divided into two groups; group 1 included 33 CBCT of patients with premolar exodontic and finished orthodontic treatment, and group 2 included 30 CBCT of patients without premolar exodontic or orthodontic treatment. The tomography were analyzed with the CS 3D Imaging Software program taking two measurements with respect to: a) distal root of the second upper molar and b) middle maxillary suture with respect to the greater palatine foramen. Results: the average age of the patients in group 1 was 30.76 and in group 2 it was 44.2; female sex prevailed in both groups. In group 1, the distance from the GPF to the MMS on the right side was 14.16 ± 0.80 mm and on the left side 14.28 ± 0.96 mm; With respect to the anatomical reference of the distal root of the second upper molar, the right side was 10.04 ± 2.19 mm and the left was 10.40 ± 2.53 mm. In group 2, the distance from the GPF to the MMS on the right side was 13.59 ± 2.96 mm and from the left side of 14.32 ± 1.04 mm. Regarding the anatomical reference of the distal root of the second upper molar, the right side was 8.15 ± 3.18 mm and the left was 8.14 ± 3.83 mm in patients with premolar exodontics and finished orthodontic treatment. The reference of the greater palatine foramen with respect to the middle maxillary suture does not vary in patients without premolar exodontics and orthodontic treatment; while in relation to the distal root of the second molar there was a statistically significant difference between the mean distance of the greater palatine foramen and the distal root of the second molar on the right side of group 1 (M = 10.04 SD = 2 , 19) and the mean distance of the greater palatine foramen than the distal root of the second right molar of group 2 (M = 8.15 SD = 3.18) p <0.05. Similarly, there was a statistically significant difference between the distance of the greater palatine foramen to the left second molar distal root in group 1 (Me = 10 RI = 2) and group 2l (Me = 7.60 RI = 6.1 ) p <0.05.Conclusion: it is important to consider the CBCT as a diagnostic tool for the study of anatomical structures that cannot be seen through other imaging modalities. In procedures that require an extensive palate graft, the greater palatine foramen can be an anatomical obstacle, which with the use of CBCT can provide the clinician a safer surgery. The present study showed a stadistically significant difference between the distance of the GPF to the distal root of the second upper molar, on the left and right side, in patients with premolar exodontics and finished orthodontic treatment.Especialista en PeriodonciaEspecializació

¿Por qué no cansarse? : Cuando el mensaje está en el cuerpo juvenil

Con el objetivo de analizar los sentidos que los jóvenes le atribuyen al cuerpo, a partir de la tensión de dos discursos antagónicos y hegemónicos- que pregonan por un lado el descontrol, lo grotesco, la embriaguez y lo exacerbado, y por otro, la responsabilidad, la estructura, la obligatoriedad y el disciplinamiento-, esta investigación propone la categoría “cuerpo cansado” para visualizar la construcción del cuerpo joven de los estudiantestrabajadores en la ciudad de La Plata. La serie de entrevistas realizadas enfatizaron en los significados, la interpretación y la reapropiación discursiva de los conceptos claves: discurso, cuerpo, joven. Este trabajo analiza la vigencia de los discursos mencionados, la reapropiación de los mismos por parte de los jóvenes como constituyentes de su realidad y la legitimación del cuerpo como concepción social y cultural.Facultad de Periodismo y Comunicación Socia

DOES THE FILM FORMED BY THE BORDEAUX MIXTURE ON THE LEAF SURFACE OF FIG TREES AFFECT PHOTOCHEMICAL PROCESSES?

The objective of this work was to evaluate if the layer formed by the Bordeaux mixture on the leaf surface alters the characteristics of gas exchange, as well as the Fluorescence of chlorophyll A, when applied to combat rust. The experimental design used was entirely randomized with 2 treatments (with and without Bordeaux mixture) with leaves in 3 distinct parts of the plant branch (apical, median and basal), with 5 evaluations in 4 repetitions. The gas exchange evaluations were related to: carbon variation between the external environment and the analysis chamber, leaf temperature, transpiration rate, stomatal conductance and net photosynthesis rate. The chlorophyll A fluorescence evaluations were: maximum quantum yield of the photosystem, effective quantum yield of the photosystem, electron transport rate and photochemical and non-photochemical dissipation. In addition to the leaf area. The film formed by the Bordeaux mixture application did not interfere in the photochemical stages of photosynthesis and the fluorescence of chlorophyll A. The internal CO2 concentration, and net CO2 assimilation are gas exchange variables influenced by the position of the leaf on the branch over time. The leaves in the middle part of the branch showed the largest area, to the detriment of the apical and basal parts of the branch.ABSTRACT: This work aimed to evaluate changes in gas exchanges and chlorophyll a fluorescence in fig plants due to the film formed on the leaf surface by Bordeaux mixture applied to control rust. The experiment was conducted in an orchard with 7-month-old fig trees of the cultivar Roxo de Valinhos, in April 2020. A completely randomized experimental design with four replications was used, consisting of two treatments (with and without application of Bordeaux mixture), evaluating leaves in three different parts of the branch (apical, middle, and basal) in five evaluations. The evaluated gas exchange parameters were: carbon, leaf temperature, transpiration, stomatal conductance, and photosynthesis. The evaluated chlorophyll fluorescence parameters were: maximum and effective quantum yield of the photosystem, electron transport rate, photochemical and non-photochemical quenching, and leaf area. The film formed by Bordeaux mixture application did not affect the photochemical phases of photosynthesis and chlorophyll a fluorescence. The leaf position on the branch affected internal CO2 concentration and net CO2 assimilation over time. Leaves in the middle part of the branch presented larger leaf areas than those in the apical and basal parts. Keywords: Ficus Carica L.; chlorophyll a; rust; leaf area.   A película formada pela calda bordalesa na superfície foliar das figueiras interfere nos processos fotoquímicos?   RESUMO: O objetivo desse trabalho foi avaliar se a camada formada pela solução da calda bordalesa na superfície foliar altera as características das trocas gasosas, bem como a Fluorescência da clorofila A, quando aplicada no combate a ferrugem. O delineamento experimental utilizado foi o inteiramente casualizado com 2 tratamentos (com e sem calda bordalesa) com folhas em 3 partes distintas do ramo da figueira (apical, mediana e basal), sendo feitas 5 avaliações, com 4 repetições, em um pomar de 7 meses de idade da cultivar Roxo de Valinhos, no mês de abril de 2020. As avaliações das trocas gasosas foram referentes a: variação do carbono, temperatura da folha, transpiração, condutância estomática e fotossíntese. As avaliações da fluorescência da clorofila A, foram referentes a: rendimento quântico máximo e efetivo do fotossistema, taxa de transporte de elétrons, dissipação fotoquímica e não fotoquímica e área foliar. A película formada pela aplicação da calda bordalesa não interferiu nas etapas fotoquímicas da fotossíntese e na fluorescência da clorofila A. A Concentração interna, e a assimilação líquida do CO2 foram influenciadas pela posição da folha no ramo ao longo do tempo. As folhas da parte mediana do ramo apresentam a maior área, em detrimento das partes apical e basal. Palavras-chave: Ficus Carica L.; clorofila A; ferrugem; área foliar

a case report

personBACKGROUND: Anaplastic thyroid carcinoma (ATC) is one of the most aggressive solid tumors. ATC is frequently diagnosed at advanced stages with unresectable disease and palliative care is often indicated. Recently, several patient-tailored therapies for ATC are emerging due to advances in molecular profiling of these tumors. Entrectinib is a potent oral selective inhibitor of neutrotrophic tropomyosin receptor kinase (NTRK), ROS1, and anaplastic lymphoma kinase fusions. The experience regarding ATC and other thyroid carcinomas, particularly in the neoadjuvant setting, is minimal. CASE REPORT: We present a case of a 51-year-old female patient presenting with a bulky mass of the left thyroid lobe measuring 100 × 108 × 80 mm that was considered surgically unresectable. While waiting for next-generation sequence (NGS) profiling, lenvatinib was initiated. There was an initial clinical and imagiologic response; however, progression occurred after 12 weeks, and at this time NGS identified an ETV6-NTRK3 fusion and entrectinib was started. After 12 weeks, tumor diameters reduced to a minimum of 68×60×49 mm, and the patient underwent total thyroidectomy plus central lymphadenectomy. Histological diagnosis confirmed an ATC (pT4a R2 N1a). Adjuvant radiotherapy (RT) (60 Grays) with weekly paclitaxel (45 mg/m2) was then administered followed by maintenance entrectinib 600 mg daily. Fluorodeoxyglucose positron emission tomography performed 3 months after completion of RT showed only non-specific uptake in the posterior wall of the hypopharynx and larynx, suggestive of inflammation. CONCLUSION: We report the first case of an ATC with a dramatic response to neoadjuvant therapy with entrectinib, which enabled surgical resection of an ab initio unresectable tumor.publishersversionpublishe

nifH pyrosequencing reveals the potential for location-specific soil chemistry to influence N2-fixing community dynamics

A dataset of 87 020 nifH reads and 16 782 unique nifH protein sequences obtained over 2 years from four locations across a gradient of agricultural soil types in Argentina were analysed to provide a detailed and comprehensive picture of the diversity, abundance and responses of the N2-fixing community in relation to differences in soil chemistry and agricultural practices. Phylogenetic analysis revealed an expected high proportion of Alphaproteobacteria, Betaproteobacteria and Deltaproteobacteria, mainly relatives to Bradyrhizobium and Methylosinus/Methylocystis, but a surprising paucity of Gammaproteobacteria. Analysis of variance and stepwise regression modelling suggested location and treatment-specific influences of soil type on diazotrophic community composition and organic carbon concentrations on nifH diversity. nifH gene abundance, determined by quantitative real-time polymerase chain reaction, was higher in agricultural soils than in non-agricultural soils, and was influenced by soil chemistry under intensive crop rotation but not under monoculture. At some locations, sustainable increased crop yields might be possible through the management of soil chemistry to improve the abundance and diversity of N2-fixing bacteriaFil: Collavino, Mónica Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Nordeste. Instituto de Botánica del Nordeste (i); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Biotecnología y Biología Molecular; ArgentinaFil: Tripp, H. James. University of California. Department of Ocean Sciences; Estados UnidosFil: Frank, Ildiko E.. University of California. Department of Ocean Sciences; Estados UnidosFil: Vidoz, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Nordeste. Instituto de Botánica del Nordeste (i); ArgentinaFil: Calderoli, Priscila Anabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Biotecnología y Biología Molecular; ArgentinaFil: Donato, Mariano Humberto. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Sistemática y Biología Evolutiva; ArgentinaFil: Zehr, Jonathan P.. University of California. Department of Ocean Sciences; Estados UnidosFil: Aguilar, Orlando Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Biotecnología y Biología Molecular; Argentin

Hemorrhagic Meningoencephalomyelitis Due to Ectopic Localization of Aelurostrongylus abstrusus in a Cat: First Case Report

The lungworm Aelurostrongylus abstrusus is one of the main causes of respiratory diseases in cats worldwide. This report describes the unusual case of a kitten infected with A. abstrusus and presented to a veterinary clinic in Brazil with lethargy, dysphagia, non-ambulatory tetraplegia, and pelvic limbs bilateral myoclonus. The clinical picture of the kitten worsened with generalized flaccid tetraplegia and death a few days after hospitalization. At necropsy, hemorrhagic necrosis and subarachnoid hemorrhages were detected in several areas of the central nervous system. Nematode stages were found at post-mortem histological examinations in lungs, cerebellum, subarachnoid space of the brain and spinal cord. Microscopic and molecular (PCRs-coupled-sequencing protocols) examination showed the presence of A. abstrusus in histological samples. This study describes the first neurological aelurostrongylosis due to ectopic localization of adult worms in the central nervous system of a cat, causing acute hemorrhagic multifocal meningoencephalomyelitis. Further studies are necessary to elucidate whether unusual localizations and the migration of A. abstrusus are more frequent than expected