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Purpose: The objective of this study is to improve our understanding of soil organic matter (SOM) stability in Brazilian Cerrado, by interpreting soil properties at the ecosystem scale and elaborating on the interactions of biotic, climatic and edaphic controls. Methods: Three 2 m soil profiles with significantly different total organic carbon TOC content but located on the same geomorphological unit were studied for δ13C isotopic composition to connect tree-grass patterns to TOC content. To gain insight into soil carbon stability, C/N, δ13C and δ15N were analysed for functional organic matter (OM) pools: free particulate OM (POM), occluded POM, base-extractable OM, and mineral-associated OM. Results: Small but abrupt shifts of δ13C with depth reflected simultaneous changes in tree-grass vegetation patterns over the past 10,000 years in all three profiles. These temporal changes were superimposed on spatial differences as indicated by consistent differences in δ13C values between the profiles, reflecting that site-specific differences in tree-grass patterns persisted over the past 10,000 years. Profiles with a historically larger contribution from trees (as evidenced by lower δ13C) had increased charcoal contents. Downward movement of charcoal by intense bioturbation occurred faster in the OM-rich soils as suggested by 14C dating. Conclusion: We found that long-term carbon storage in Brazilian Cerrado soils was a conjunction of wildfires, bioturbation, and local edaphic controls on tree-grass composition. Soils with an OM-rich thick A-horizon had more trees, more charcoal, and a higher activity of soil macrofauna, which was related to local differences in soil water availability.

Potentially toxic elements (PTEs) are of great concern in steel mill wastes. Therefore, in order to use them as potential fertilizers in soil, risk assessments are needed. Three steel mill wastes were tested as possible amendments for soils at seven different doses (0, 0.5, 1, 2, 4, 8, 16 t ha−1): phosphate mud (PM), metallurgical press residue (MPR), and filter press mud (FPM) during rice cultivation in a pot experiment in a Haplic Gleisol. Analysis on rice tissues, including roots, shoots, husk, and grains, were conducted and contents of Cu, Cd, Ni, Zn, Mn, and Pb were assessed. Translocation and bioaccumulation factors were calculated for each element. In general, PTEs are more accumulated in roots and greater contents of Zn and Mn were found, while the lowest ones were found for Pb, probably due to its lack of functional roles during plants development. Higher translocation was observed for Mn, which is associated to the redox conditions of rice cultivation and the high mobility of this element under this condition. Application of steel mill wastes can increase PTE bioavailability and translocation factors, especially PM, but all of the wastes reveal a high hazard index.

Synthetic chelating agents have high cost and low biodegradation in the environment; thus, the use of natural complexing agents for iron increases the sustainability in crop production. The aim of ...

Zinc deficiency is widespread in cultivated soils, limiting the grain crop production and the adequate human nutrition. Several wastes from metallurgical activity can be used as Zn source, but these materials generally also have other potentially toxic elements, such as Pb, that can be highly toxic for plants and humans. This study aimed to evaluate the efficiency of five chemical extractors (water, citric acid, DTPA, Mehlich 1, and USEPA 3051A) in better correlating with the bioavailable contents of Zn and Pb in soils treated with steel mill wastes (metallurgic press residue (MPR), filter press mud (FPM), and phosphate mud (PM)). Rice plants were cultivated in pots with 4 kg of a Haplic Eutrophic Gleisol and steel mill wastes were applied in soil at increasing doses (0, 0.5, 1, 2, 4, 8, and 16 t ha-1). The availability of the potentially toxic elements Zn and Pb was assessed as total contents in rice shoots, grains, husks, and roots. The results showed that the USEPA 3051A method extracted greater contents of Zn and Pb from soil compared with other extractants. Due to their greater natural Pb and Zn contents, MPR and PM promoted higher contents of these elements in soils, respectively. Doses of PM influenced Zn contents in grains. After adding 16 t ha-1 of PM, Zn content in rice grains was 0.1 mg kg-1. However, at doses 0.5, 1, 2, and 4 t ha-1, the average concentration of Zn in the grains was 40 mg kg-1. The wastes MPR and FPM at 16 t ha-1 promoted Zn concentration in grains of 42 and 45 mg kg-1, respectively. The greatest contents of Pb in grains were found after addition of FPM at doses 0.5, 1, and 2 t ha-1: 6.67, 4.96, and 0.45 mg kg-1, respectively, and above 4 t ha-1 (4, 8, and 16 t ha-1); Pb content in grains was less than 0.3 mg kg-1. The content of Pb in roots at 16 t ha-1 of PM, MPR, and FPM was 18, 25, and 155 mg kg-1, respectively, and for Zn, under the same conditions, 100, 255, and 813 mg kg-1 for MPR, FPM, and PM, respectively. USEPA 3051A can be used to assess Pb and Zn available contents, and positive correlations with bioavailable contents of these elements in roots prove its feasibility. Further studies are necessary to state the safety of using steel mill application, including the use of other crop species, but PM is a promising waste for soil Zn fertilization.

The relation between chemical attributes of complexed Fe sources and the efficiency of foliar fertilization is still unclear. This study aimed to investigate the influence of Fe-complex stability o...

Potentially toxic elements (PTE’s) are of great concern in steel mill wastes. Therefore, in other to use them as potential fertilizers in soil, risk assessments are needed. Three steel mill wastes were tested as possible amendments for soils at six different doses (0; 0,5; 1; 2; 4; 8; 16 t ha-1): Phosphate mud (PM), Metallurgical press residue (MPR) and Filter press mud (FPM) during rice cultivation in a pot experiment in a Haplic Gleisol. Analysis on rice tissues, including roots, shoots, husk and grains were conducted and contents of Cu, Cd, Ni, Zn, Mn and Pb were assessed. Translocation and bioaccumulation factors were calculated for each element. In general, PTE’s are more accumulated in roots and greater contents of Zn and Mn were found, while the lowest ones were found for Pb, probably due to its lack of functional roles during plants development. Higher translocation was observed for Mn, which is associated to the redox conditions of rice cultivation and the high mobility of this element under this condition. Application of steel mill wastes can increase PTE’s bioavailability and translocation factors, especially PM, but all of the wastes reveal a high hazard index.

Potentially toxic elements (PTEs) are of great concern in steel mill wastes. Therefore, in order to use them as potential fertilizers in soil, risk assessments are needed. Three steel mill wastes were tested as possible amendments for soils at seven different doses (0, 0.5, 1, 2, 4, 8, 16 t ha

Zinc deficiency is widespread in cultivated soils, limiting the grain crop production and the adequate human nutrition. Several wastes from metallurgical activity can be used as Zn source, but these materials generally also have other potentially toxic elements, such as Pb, that can be highly toxic for plants and humans. This study aimed to evaluate the efficiency of five chemical extractors (water, citric acid, DTPA, Mehlich 1, and USEPA 3051A) in better correlating with the bioavailable contents of Zn and Pb in soils treated with steel mill wastes (metallurgic press residue (MPR), filter press mud (FPM), and phosphate mud (PM)). Rice plants were cultivated in pots with 4 kg of a Haplic Eutrophic Gleisol and steel mill wastes were applied in soil at increasing doses (0, 0.5, 1, 2, 4, 8, and 16 t ha

The disease caused by the new coronavirus, or COVID-19, has been recently described and became a health issue worldwide. Its diagnosis of certainty is given by polymerase chain reaction. High-resolution computed tomography, however, is useful in the current context of pandemic, especially for the most severe cases, in assessing disease extent, possible differential diagnoses and searching complications. In patients with suspected clinical symptoms and typical imaging findings, in which there is still no laboratory test result, or polymerase chain reaction is not available, the role of this test is still discussed. In addition, it is important to note that part of the patients present false-negative laboratory tests, especially in initial cases, which can delay isolation, favoring the spread of the disease. Thus, knowledge about the COVID-19 and its imaging manifestations is extremely relevant for all physicians involved in the patient care, clinicians or radiologists. RESUMO A doença causada pelo novo coronavírus, ou COVID-19, foi descrita recentemente e tornou-se uma questão de saúde mundial. Seu diagnóstico de certeza é dado pela reação em cadeia da polimerase. A tomografia computadorizada de alta resolução, entretanto, mostra-se útil no contexto atual de pandemia, especialmente nos casos mais graves, na avaliação da extensão da doença, em possíveis diagnósticos diferenciais e na pesquisa de complicações. Em pacientes com quadro clínico suspeito e achados de imagem típicos, nos quais ainda não há resultado laboratorial ou a reação em cadeia da polimerase não se encontra disponível, ainda se discute o papel desse exame. Importante ressaltar que parte dos pacientes apresenta exames laboratoriais falsos-negativos, notadamente em casos iniciais, o que pode retardar medidas de isolamento, favorecendo a propagação da doença. Dessa forma, o conhecimento da COVID-19 e de suas manifestações nos exames de imagem é de extrema importância para os médicos envolvidos no atendimento, sejam clínicos ou radiologistas.

Ground-glass opacity is a very frequent and unspecified finding in chest computed tomography. Therefore, it admits a wide range of differential diagnoses in the acute context, from viral pneumonias such as influenza virus, coronavirus disease 2019 and cytomegalovirus and even non-infectious lesions, such as vaping, pulmonary infarction, alveolar hemorrhage and pulmonary edema. For this diagnostic differentiation, ground glass must be correlated with other findings in imaging tests, with laboratory tests and with the patients’ clinical condition. In the context of a pandemic, it is extremely important to remember the other pathologies with similar findings to coronavirus disease 2019 in the imaging exams. RESUMO A opacidade em vidro fosco é uma alteração muito frequente e pouco específica na tomografia computadorizada de tórax. Ela admite grande leque de diagnósticos diferenciais no contexto agudo, desde pneumonias virais, como as causadas pelo vírus influenza, pela doença do coronavírus 2019 e pelo citomegalovírus, até mesmo lesões de origem não infecciosa, como vaping , infarto pulmonar, hemorragia alveolar e edema pulmonar. Para essa diferenciação diagnóstica, deve-se correlacionar o vidro fosco com os demais achados nos exames de imagem, exames laboratoriais e quadro clínico do paciente. É de suma importância, no contexto de pandemia, recordar as demais patologias com os achados semelhantes aos da doença do coronavírus 2019 nos exames de imagem.

Important parameters that influence biochar properties include charring temperature and biomass type. We characterized the molecular properties of biochars from five agricultural residues with pyrolysis gas chromatography mass/spectrometry (pyrolysis-GC/MS) in comparison with atomic H/C and N/C ratios. Feedstocks included chicken manure, eucalyptus sawdust, coffee husk, sugarcane bagasse and pine bark. Biochars produced at three different temperatures (Tchar) were analyzed, including 350, 450 and 750 °C, as well as the uncharred materials. The optimum temperature during analysis with pyrolysis-GC/MS (Tpy) was examined. Tpy 600 °C gave the best results for all Tchar by showing a larger diversity of pyrolysis products compared to Tpy 700 °C and 800 °C; Tpy 600 °C was therefore used for qualitative and quantitative comparison of the samples. Charring temperature was the dominant factor that determined the chemical composition of the biochar pyrolysates. Uncharred feedstocks had the largest contribution from carbohydrates, lignin phenols and long chain n-alkanes, all of which rapidly decreased with charring; biochars produced at Tchar 350 and 450 °C showed the largest contribution from phenols, mid-chain n-alkanes, benzofurans, indenes, biphenyls and PAHs, from which the benzofurans, indenes, biphenyls and PAHs were particular abundant in samples produced at Tchar 450 °C; pyrolysates of biochars produced at Tchar 750 °C were characterized by branched aliphatics, short chain n-alkanes/n-alkenes and low molecular weight (LMW) benzenes. Factor analysis showed that the variation of products differed largely within some chemical groups. For the N-containing compounds, caffeine, C16 alkylnitrile and diketopiperazines were associated with uncharred materials, benzonitriles and quinolines were associated with Tchar 350–450 °C. Another part of the variation of N-containing compounds was associated with chicken manure, and to a lesser extend also coffee husk, independently of Tchar. For all five agricultural residues, the highest chemical diversity was found for biochar produced at Tchar 350 °C. As the charring temperature increased, the diversity of pyrolysis products diminished.

The disease caused by the new coronavirus, or COVID-19, has been recently described and became a health issue worldwide. Its diagnosis of certainty is given by polymerase chain reaction. High-resolution computed tomography, however, is useful in the current context of pandemic, especially for the most severe cases, in assessing disease extent, possible differential diagnoses and searching complications. In patients with suspected clinical symptoms and typical imaging findings, in which there is still no laboratory test result, or polymerase chain reaction is not available, the role of this test is still discussed. In addition, it is important to note that part of the patients present false-negative laboratory tests, especially in initial cases, which can delay isolation, favoring the spread of the disease. Thus, knowledge about the COVID-19 and its imaging manifestations is extremely relevant for all physicians involved in the patient care, clinicians or radiologists.

Several chemical properties of complexes should be considered to base their suitable applications in agronomic and environmental domains. However, the determination of these characteristics is generally expensive and time consuming. Therefore, the prediction of properties in complexes using a simple and expeditious technique, such as infrared spectroscopy, is highly desirable. This study aimed to investigate the molecular structure and chemical properties of metal complexes, such as stability, metal complexed fraction, and solubility. The complexes were submitted to experimental FTIR analysis and the spectroscopic data were regressed against the above-mentioned properties using partial least squares (PLS) to obtain a predictive model. Low molecular weight carboxylic acids (citric acid, malic acid, tartaric acid, and oxalic acid) were used as complexing agents for three metals (Mn, Zn, and Fe) in two stoichiometric ratios of reaction (1:1 and 1:2, metal: ligand molar ratio). Solubility and complexation ratio appeared to be dependent on the ligand and stoichiometry. Citrate and oxalate have formed the most stable complexes with the tested metals. Metal-oxalates tend to form 1:2 complexes at the pH and stoichiometries tested, whereas citrate, malate, and tartrate tend to form 1:1 complexes. All the complexes exhibited monodentate coordination of carboxylic groups with metals. Overall, the predictive models were built to estimate the solubility and the ratio of complexed metals. Furthermore, the coordination mode of ligands to metals could also be assigned from infrared band shifts of the carboxylate groups. This work revealed crucial chemical properties to base the use of complexes, and show that the fast and non-destructive FTIR technique can be used for predict these properties.

Humic (HA) and fulvic (FA) acids improve the nutrient availability and uptake by plants but some aspects of their agronomic use still need to be clarified. The effects of HA soil application and FA foliar application on the growth, Zn and B uptake by coffee seedlings were evaluated. HA was added to an Oxisol at concentrations 0, 10, 25, 50, 75 and 100 mg kg−1 (C-HA), in both limed (pH 6.2) and overlimed (pH 7.2) conditions. FA (0, 0.2, 0.5 and 1 g L−1 C-FA) was applied to coffee leaves in three different application modes (M): with 0.3% Zn and 0.6% B supplied via foliar (M1), 0.6% B and 1.2% Zn supplied via foliar (M2) and 1.2 mg kg−1 B and 6 mg kg−1 Zn supplied via soil (M3). HA addition in soil significantly (p 1 and M2, FA application significantly (p −1 and B accumulation at 0.96 and 0.45 g L−1 C-FA. Foliar application of C-FA, instead soil application of C-HA, is a suitable practice to improve coffee seedlings growth and nutrition on Oxisol.

Purpose Elbow flexion deficit is a frequent problem in traumatic brachial plexus injuries and reestablishment of this function is the primary treatment goal. When management is delayed, or the initial acute approach fails, free functional transfer of the gracilis muscle for elbow flexion is the treatment of choice. In this report, the authors present the results of a comparison study on different donor nerves (spinal accessory and ulnar) in elbow flexion reconstruction with gracilis flap for traumatic adult brachial plexus injuries. Methods Retrospective analysis of patients with both total or partial traumatic brachial plexus injuries was carried out. Of the 38 patients enrolled, 37 were male (97.4%) with a mean age of 28.3 years. The mean follow-up period was 25 months. Postoperative function of the gracilis muscle flap was recorded and patients were divided into two groups according to donor nerve: spinal accessory nerve (SAN) (18 cases), and motor fascicles of the ulnar (ULNAR) (20 cases). Results Twenty-six cases obtained elbow flexion strength M3 or M4 (68.4%): 0 M0 (0.0%), 4 M1 (10.5%), 8 M2 (21.1%), 9 M3 (23.7%) and 17 M4 (44.7%). The mean interval to first recorded M3 muscular strength was 12.4 months. Functional elbow flexion strength (≥ M3) had the following distribution: SAN 83.3% (15/18) and ULNAR 55.0% (11/20) (p = .086). Conclusion No statistical difference for final muscle strength was found between donor nerve groups.

A matéria orgânica do solo (MOS) representa um importante reservatório de carbono (C) nos ecossistemas terrestres. O conteúdo de C estocado no solo pode ser liberado para a atmosfera na forma de CO2, com a decomposição da MOS, ou pode ser aumentado com a entrada de resíduos e retenção da MOS. Nesse sentido, é importante entender os mecanismos de estabilidade e retenção da MOS para predizer como os solos respondem a mudanças, quer sejam elas induzidas por alterações climáticas ou por práticas de manejo. Dentro dos Latossolos, classe que ocupa cerca de 32 % do território brasileiro, há aqueles que possuem horizonte A húmico hiper espesso e, portanto, com maior estoque de C. Aspectos sobre a origem, formação e preservação do horizonte A húmico destes solos em suas ocorrências em diferentes biomas ainda não foram completamente elucidados e estão estritamente ligados à fonte, dinâmica e mecanismos de preservação e distribuição da MOS no solo. O objetivo deste trabalho é entender a gênese da MO dos Latossolos húmicos que ocorrem no Bioma Cerrado, por meio da caracterização molecular pela técnica da pirólise acoplada à cromatografia gasosa e espectroscopia de massas (pirólise - CG/EM). Para isso, foram coletadas amostras dos horizontes A em dois perfis de Latossolos com horizonte A húmico (LH1, LH2) e um perfil de Latossolo com horizonte A moderado (solo de referência; LNH) situados em superfície de aplanamento adjacente à Serra do Espinhaço, no município de Grão Mogol - MG, sob clima tropical semi-úmido e vegetação de cerrado sensu strictu. Por meio da descrição morfológica dos solos em diferentes níveis de observação (campo, lupa e microscópio) procurou-se entender melhor os mecanismos de espessamento do horizonte A e a distribuição de partículas de carvão ao longo do perfil. As amostras dos horizontes foram submetidas ao fracionamento físico e extração da MOS, gerando as seguintes frações: fração leve livre (FLL); fração leve oclusa (FLO), fração extraível com NaOH (EXT) e resíduo (RES). A morfologia dos perfis evidencia a intensa e longa atividade biológica (fauna e raízes) a que esses solos foram e estão submetidos. Isso explica a abundância de microagregados e a consequente macropososidade elevada, assim como a ampla distribuição de fragmentos de carvão em todo o horizonte A, e parte do B, com dimensões milimétricas a submilimétricas, sugerindo a fragmentação destes ao longo do tempo. Foi evidenciado o maior conteúdo de carvões nos dois LHs em comparação ao LNH. A distribuição da MOS nas frações estudadas foi a mesma para os três perfis estudados: RES>EXT>FLL>FLO, que mostra a importância da fração RES para estes solos. Produtos da carbonização (Black carbon; BC: hidrocarbonetos poliaromáticos) foram mais abundantes na fração RES e FLO, no entanto, a maior diferença qualitativa entre a MOS de LHs e LNH diz respeito à abundância de BC na fração RES, que é maior em LHs do que LNH; confirmando a maior quantidade de carvões em LHs verificada na morfologia. Um índice de degradação do BC foi estabelecido com base em análise fatorial com os todas as frações estudadas e produtos poliaromáticos. Este índice, aplicado às frações EXT e RES, mostrou que a degradação do BC aumenta com a profundidade/idade, e não houve diferenças significativas entre os perfis estudados. Portanto, LHs provavelmente tem maior entrada de carvões, o que deve estar ligado a um histórico de maior incidência de incêndios ou maior abundância local de espécies arbóreas. Soil organic matter (SOM) is an important carbon (C) stock in terrestrial ecosystems. C in soils can be released to the atmosphere in CO2 form by SOM decomposition, or can be stored with residue inputs and SOM retention in the soils. In this sense, it is important to understand the SOM stability mechanisms to predict how soils behave under climatic or human management induced environmental changes. Latosols occupy 40% of the national territory in Brazil. Some of them have a hyper thick A horizon with a major C stock, Humic Latasols. Aspects that underlie the formation of humic A horizon are still unclear, and mainly concern SOM dynamics, SOM preservation mechanisms, and SOM distribution with depth. The aim of this work is to understand the genesis of Humic Latosols through molecular characterization of SOM by pyrolysis coupled to gas chromatography and mass spectrometry (pyrolysis - GC/MS). For this purpose samples from two profiles (LH1, LH2) were collected, and in addition a reference profile was sampled (Latosol without humic characteristics, LNH). All profiles were located near Grão Mogol city (MG) under a semi-humid tropical climate and Cerrado vegetation. Morphology at different levels (field, bloom and microscope) showed that charcoal was abundant in all three profiles, and an extremely high biological activity. Profiles were sampled in detail and all samples were submitted to sequential physical fractionation and chemical extraction, generating the following SOM fractions: free light fraction (FLF); occluded light fraction (OLF); NaOH extractable fraction (EXT) and residue (RES). The molecular composition of the samples was studied by pyrolysis-GC/MS. Profile morphology evidence the long and intense biological activity (faunal and roots) in this soils, in the past and present time. This explains the microaggregate abundance and consequent macroporosity, and also the distribution of charcoal fragments in all of A and part of B horizon. These fragments have submilimetrical a milimetrical dimensions, suggests its fragmentation along the time. It was evidenced too, the bigger charcoal content in LHs than LNH. The C distribution in the fractions was the same for all the studied profiles: RES>EXT>FLL>FLO, which shows the importance of the RES fraction for these soils. Pyrolysis products derived from black carbon (BC; polyaromatics hydrocarbons) were most abundant in RES and FLO. In the RES, PAHs were more abundant in the LH than LNH; confirming the biggest quantity of charcoals in LHs verified in morphology. A BC degradation index was established using factor analysis with all PAH and all fractions studied. Depth records of these parameter showed an increase with depth in both EX and RES, and showed no differences between the studied profiles. It is concluded, therefore, that the LH had a larger input of charcoal. It is hypothesized that the larger contribution from BC in LHs is related to local differences in fire intensity and/or more trees in the vegetation.

OBJECTIVE: Gain in elbow flexion in patients with brachial plexus injury is extremely important. The transfer of a fascicle from the ulnar nerve to the motor branch of the musculocutaneous nerve (Oberlin surgery) is a treatment option. However, in some patients, gain in elbow flexion is associated with wrist and finger flexion. This study aimed to assess the frequency of this association and the functional behavior of the limb. METHODS: Case-control study of 18 patients who underwent the Oberlin surgery. Group 1 included patients without disassociation of range of elbow flexion and that of the fingers and wrist; Group 2 included patients in whom this disassociation was present. In the functional evaluation, the Sollerman and DASH tests were used. RESULTS: It was observed that 38.89% of the patients did not present disassociation of elbow flexion with flexion of the wrist and fingers. Despite the existence of a favorable difference in the group with disassociation of the movement, when the Sollerman protocol was applied to the comparison between both groups, this difference was not statistically significant. With the DASH test, however, there was a statistically significant difference in favor of the group of patients who managed to disassociate the movement. CONCLUSION: The association of elbow flexion with flexion of the wrist and fingers, in the group studied, was shown to be a frequent event, which influenced the functional result of the affected limb. RESUMO OBJETIVO: O ganho da flexão do cotovelo em pacientes com lesão no plexo braquial é de suma importância. A cirurgia de transferência de fascículo do nervo ulnar para ramo motor do nervo musculocutâneo (cirurgia de Oberlin) é uma opção de tratamento. Contudo, o ganho da flexão do cotovelo, em alguns pacientes, vem associado à flexão do punho e dos dedos. O objetivo deste trabalho é avaliar a frequência dessa associação e o comprometimento funcional do membro. MÉTODOS: Estudo tipo caso-controle de 18 pacientes submetidos à cirurgia de Oberlin. No Grupo 1 foram incluídos os pacientes que não apresentavam dissociação do ganho da flexão do cotovelo com a dos dedos e do punho; no Grupo 2, os pacientes em que havia dissociação. Os testes de Sollerman e Disabilities of the Arm, Shoulder and Hand (Dash) foram usados na avaliação funcional. RESULTADOS: Observou-se que 38,89% dos pacientes não dissociavam flexão de cotovelo de flexão de punho e dos dedos. Apesar de existir uma diferença favorável ao grupo que dissociava o movimento quando aplicado o protocolo de Sollerman na comparação entre os pacientes dos dois grupos, essa não se mostrou estatisticamente significante. Já no teste Dash, observou-se diferença estatisticamente significante, favorável ao grupo de pacientes que consegue dissociar o movimento. CONCLUSÃO: A associação da flexão do cotovelo com a flexão de punho e dos dedos no grupo estudado mostrou ser um evento frequente, teve influência no resultado funcional do membro acometido.

The effect of long term degradation on soil black carbon (BC) is important for correctly interpreting the role of BC in the global carbon cycle and in biochar studies. To address this, we studied three soil profiles (0–2 m depth, > 9000 yr) in undisturbed Brazilian Cerrado vegetation naturally affected by wildfires. The molecular composition of several soil organic matter (OM) pools was studied using analytical pyrolysis. Other analyses included general chemical and physical characteristics and micromorphology. The soil OM fractions included the free light fraction (FLF; particulate OM), the occluded light fraction (OLF; particulate OM within aggregates), the 0.1 M NaOH extractable OM (EXT; comparable with the combined humic acid and fulvic acid fractions) and the remaining residue (RES; treated with HF/HCl; comparable with the humin fraction). Although each fraction represents a continuum of material, they were assigned a different degradation level. The light fractions represent relatively intact BC (i.e. charcoal) of which the OLF is more degraded than the FLF, the EXT contains more decomposed material and the RES represents residual OM that is difficult to decompose. The largest contribution to the total soil OM was from RES and EXT, together accounting for > 80% of the total soil C. The relative contribution from BC-associated pyrolysis products was generally large for all fractions (between 5% and 57%) and showed an increase with depth in the OLF and RES. Based on factor analysis exclusively applied to BC-associated pyrolysis products from all four OM fractions, two BC degradation indices were extracted: Index 1, reflecting depolymerization and relative enrichment of N, and Index 2, reflecting a relative increase in condensed structures. Both indices gradually increased with depth for all fractions, except FLF. Based on these indices, we selected some simple ratios that showed good correlation with them (r2 > 0.7). For Index 1, reflecting depolymerization, adequate ratios for all fractions included benzene/indene and benzene/C1 naphthalenes. For Index 2, reflecting the relative accumulation of condensed BC, adequate ratios for all fractions included biphenyl/C2-benzene, fluorene/C2-benzene and 4-ring PAHs/C2-benzene.

Introduction: Elbow flexion deficit is a frequent problem in traumatic brachial plexus injuries and reestablishment of this function is the primary treatment goal. When management is delayed or the initial acute approach fails, free functional transfer of the gracilis muscle for elbow flexion is the treatment of choice: the authors seek to determine which donor nerve (spinal accessory, intercostal, median, or ulnar) results in better elbow flexion after microsurgical reconstruction. Methods: Retrospective analysis of patients with traumatic brachial plexus injuries who underwent functional free gracilis muscle flap for elbow flexion between February 2003 and October 2014 was carried out. Postoperative function of the gracilis functional flap was recorded and patients were divided into 4 groups according to donor nerve: spinal accessory nerve (SAN), intercostal nerves (ICN), motor fascicles of the median (MED), and ulnar nerve (ULNAR). Cases in which a primary neurorrhaphy was not possible were further subdivided into 2 groups: SAN with graft interposition (SAN graft) and ICN with graft interposition (ICN graft). The final elbow flexion strength was evaluated by the British Medical Research Council (BMRC) scale and time in months when the authors first observed M3 muscle power was also of note. Results: Fifty-nine patients met inclusion criteria for this retrospective study. Two cases were excluded due to flap loss (3%) and 3 were lost to follow up (5%). Of the 54 patients enrolled, 53 were males (98.2%) with a mean age of 29 years. The mean follow-up period was 28 months. Thirty-four cases obtained muscle strength of ≥ M3 (62.9%), 6 M0 (11.1%), 4 M1 (7.5%), 10 M2 (18.5%), 13 M3 (24%), and 21 M4 (38.9%). The mean interval to first recorded M3 muscular strength was 16 months. Patients stratified by donor nerve achieving ≥ M3 had the following distribution: SAN 83.3% (15/18), SAN graft 50% (2/4), ICN 50% (2/4), ICN graft 33.3% (1/3), MED 40% (2/5), and ULNAR 60% (12/20). No statistical difference for final muscle strength was found between donor nerve groups. SAN transfer with graft interposition took longer to reach muscle strength of M3 or greater ( P < .05). Conclusion: Free functional gracilis muscle flap for traumatic brachial plexus injuries is a viable option for elbow flexion recovery. Comparison between 4 different nerve transfers—SAN, ICN, MED, and ULNAR—did not clearly indicate a better alternative over the others.

Gain in elbow flexion in patients with brachial plexus injury is extremely important. The transfer of a fascicle from the ulnar nerve to the motor branch of the musculocutaneous nerve (Oberlin surgery) is a treatment option. However, in some patients, gain in elbow flexion is associated with wrist and finger flexion. This study aimed to assess the frequency of this association and the functional behavior of the limb.Case-control study of 18 patients who underwent the Oberlin surgery. Group 1 included patients without disassociation of range of elbow flexion and that of the fingers and wrist; Group 2 included patients in whom this disassociation was present. In the functional evaluation, the Sollerman and DASH tests were used.It was observed that 38.89% of the patients did not present disassociation of elbow flexion with flexion of the wrist and fingers. Despite the existence of a favorable difference in the group with disassociation of the movement, when the Sollerman protocol was applied to the comparison between both groups, this difference was not statistically significant. With the DASH test, however, there was a statistically significant difference in favor of the group of patients who managed to disassociate the movement.The association of elbow flexion with flexion of the wrist and fingers, in the group studied, was shown to be a frequent event, which influenced the functional result of the affected limb.O ganho da flexão do cotovelo em pacientes com lesão no plexo braquial é de suma importância. A cirurgia de transferência de fascículo do nervo ulnar para ramo motor do nervo musculocutâneo (cirurgia de Oberlin) é uma opção de tratamento. Contudo, o ganho da flexão do cotovelo, em alguns pacientes, vem associado à flexão do punho e dos dedos. O objetivo deste trabalho é avaliar a frequência dessa associação e o comprometimento funcional do membro.Estudo tipo caso-controle de 18 pacientes submetidos à cirurgia de Oberlin. No Grupo 1 foram incluídos os pacientes que não apresentavam dissociação do ganho da flexão do cotovelo com a dos dedos e do punho; no Grupo 2, os pacientes em que havia dissociação. Os testes de Sollerman eObservou-se que 38,89% dos pacientes não dissociavam flexão de cotovelo de flexão de punho e dos dedos. Apesar de existir uma diferença favorável ao grupo que dissociava o movimento quando aplicado o protocolo de Sollerman na comparação entre os pacientes dos dois grupos, essa não se mostrou estatisticamente significante. Já no teste Dash, observou-se diferença estatisticamente significante, favorável ao grupo de pacientes que consegue dissociar o movimento.A associação da flexão do cotovelo com a flexão de punho e dos dedos no grupo estudado mostrou ser um evento frequente, teve influência no resultado funcional do membro acometido.

An 86-years-old male patient was admitted to the emergency department with a 1-day history of fever, dyspnea, and cough. After an assessment, there were no criteria that justified the patient’s hospitalization, therefore, he was dismissed and instructed to continue treatment at home. One week after the onset of symptoms, the patient returned with worsening dyspnea and persistent fever, which prompted his hospitalization. A chest computed tomography (CT) demonstrated typical coronavirus disease (COVID-19) findings(,) (), and the real-time polymerase chain reaction [...]

Motivo de grande preocupacao no cenario global atual, a pandemia pelo novo coronavirus (COVID-19) tem sido um dos grandes motivos da realizacao de tomografias computadorizadas de torax, seja na avaliacao inicial ou no controle evolutivo. Esses pacientes apresentam aumento do dimero D, achado provavelmente relacionado a um estado de hipercoagulabilidade e que marca pior prognostico.( )A seguir, ilustramos dois casos de pacientes com confirmacao laboratorial de infeccao pelo coronavirus e sinais de tromboembolismo pulmonar (TEP) – associacao ja descrita.( , [...]