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Soil organic carbon (SOC) plays an important role in regulating global climate change, carbon and nutrient cycling in soils, and soil moisture. Organic matter (OM) additions to soils can affect the rate at which SOC is mineralized by microbes, with potentially important effects on SOC stocks. Understanding how pyrogenic organic matter (PyOM) affects the cycling of native SOC (nSOC) and the soil microbes responsible for these effects is important for fire-affected ecosystems as well as for biochar-amended systems. We used an incubation trial with five different soils from National Ecological Observatory Network sites across the US and 13C-labelled 350°C corn stover PyOM and fresh corn stover OM to trace nSOC-derived CO2 emissions with and without PyOM and OM amendments. We used high-throughput sequencing of rRNA genes to characterize bacterial, archaeal, and fungal communities and their response to PyOM and OM in soils that were previously stored at -80°C. We found that the effects of amendments on nSOC-derived CO2 reflected the unamended soil C status, where relative increases in C mineralization were greatest in low-C soils. OM additions produced much greater effects on nSOC-CO2 emissions than PyOM additions. Furthermore, the magnitude of microbial community composition change mirrored the magnitude of increases in nSOC-CO2, indicating a specific subset of microbes were likely responsible for the observed changes in nSOC mineralization. However, PyOM responders differed across soils and did not necessarily reflect a common "charosphere". Overall, this study suggests that soils that already have low SOC may be particularly vulnerable to short-term increases in SOC loss with OM or PyOM additions.Importance Soil organic matter (SOM) has an important role in global climate change, carbon and nutrient cycling in soils, and soil moisture dynamics. Understanding the processes that affect SOM stocks is important for managing these functions. Recently, understanding how fire-affected organic matter (or "pyrogenic" organic matter (PyOM)) affects existing SOM stocks has become increasingly important, both due to changing fire regimes, and to interest in "biochar" - pyrogenic organic matter that is produced intentionally for carbon management or as an agricultural soil amendment. We found that soils with less SOM were more prone to increased losses with PyOM (and fresh organic matter) additions, and that soil microbial communities changed more in soils that also had greater SOM losses with PyOM additions. This suggests that soils that already have low SOM content may be particularly vulnerable to short-term increases in SOM loss, and that a subset of the soil microbial community is likely responsible for these effects.
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Hemangiomas are rarely found in the axilla, with the most commonly identified axillary mass being lymphadenopathy. We report a unique case report of a post-partum female with an axillary mass that became larger and symptomatic while breastfeeding. On imaging, the mass was found to be complex and cystic, and aspiration was attempted several times. With a rapid return of swelling and worsening symptoms, there was concern for bleeding into the cystic cavity. Ultimately, the >10 cm mass had to be formally excised in the operating room, yielding definitive relief of symptoms. Final pathology reported the mass as a vascular malformation, either a hemangioma or arteriovenous malformation. It has been postulated that estrogen and progesterone may stimulate the growth of hemangiomas, which may explain this patient's post-partum presentation. This case demonstrates a perplexing axillary mass that continued to re-accumulate until final excision.
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In this study, the suitability of biochar and activated carbon (AC) for contaminated soil remediation is investigated by determining the sorption of pyrene to both materials in the presence and absence of soil and before as well as after aging. Biochar and AC were aged either alone or mixed with soil via exposure to (a) nutrients and microorganisms (biological), (b) 60 and 110 °C (chemical), and (c) freeze-thaw cycles (physical). Before and after aging, the pH, elemental composition, cation exchange capacity (CEC), microporous SA, and sorption isotherms of pyrene were quantified. Aging at 110 °C altered the physicochemical properties of all materials to the greatest extent (for example, pH increased by up to three units and CEC by up to 50% for biochar). Logarithmic K(Fr) values ranged from 7.80 to 8.21 (ng kg(-1))(ng L(-1))(-nF) for AC and 5.22 to 6.21 (ng kg(-1))(ng L(-1))(-nF) for biochar after the various aging regimes. Grinding biochar to a smaller particle size did not significantly affect the sorption of d(10) pyrene, implying that sorption processes operate on the subparticle scale. Chemical aging decreased the sorption of pyrene to the greatest extent (up to 1.8 log unit for the biochar+soil). The sorption to AC was affected more by the presence of soil than the sorption to biochar was. Our results suggest that AC and biochar have a high sorption capacity for pyrene that is maintained both in the presence of soil and during harsh aging. Both materials could therefore be considered in contaminated land remediation.
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Carvão Vegetal/química , Recuperação e Remediação Ambiental/métodos , Pirenos/química , Poluentes do Solo/química , Solo/química , Adsorção , Hidrocarbonetos Policíclicos Aromáticos/química , Microbiologia do SoloRESUMO
BACKGROUND: Epithelioid hemangioendothelioma (EHE) is a rare malignant vascular tumor characterized by WWTR1-CAMTA1, t (1:3) (p36;q25) translocation in 90% of cases. Without prior EHE history, it can mimic other malignant effusions. Recently, CAMTA1 was published as an excellent immunohistochemical surrogate marker for molecular testing for WWTR1-CAMTA1 fusion in surgical specimens. METHODS: A 6-year retrospective search using our computer system was performed for cases diagnosed as EHE on effusion cytology and surgical specimens. The clinical presentation, cytologic findings and immunohistochemical stain results, including CAMTA1 were reviewed. RESULTS: Four pleural and one peritoneal effusions were identified. The median age was 52 years with a female to male ratio of 3:2. Most patients presented with pulmonary symptoms. The cytologic features were non-specific easily mimicking other malignancies; especially in the absence of known prior malignancy. This was exemplified by one of our cases which was initially misdiagnosed as adenocarcinoma. Intracytoplasmic erythrocytes were present only on the cell blocks but not on cytology. The cytology cell blocks from patients with prior EHE confirmed on surgical biopsies stained positive for vascular markers (CD31, ERG) and CAMTA1. CONCLUSION: The features of EHE in effusion are non-specific and a diagnostic pitfall in cytology. In the absence of prior EHE diagnosis, inclusion of this entity in the differential diagnoses and application of immunohistochemical stain panels will be prudent in avoiding a misdiagnosis. However, in cases with prior EHE diagnosis, CAMTA1 could serve as diagnostic marker; especially on limited cytology material. Additional studies will be helpful in supporting our results.
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Hemangioendotelioma Epitelioide/diagnóstico , Hemangioendotelioma Epitelioide/patologia , Adulto , Idoso , Biomarcadores Tumorais/genética , Proteínas de Ligação ao Cálcio/genética , Feminino , Hemangioendotelioma Epitelioide/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Transcrição/genética , Translocação Genética/genéticaRESUMO
The Revised fourth Edition World Health Organization (WHO) Classification of Tumors of Hematopoietic and Lymphoid Tissues suggests novel categories, including "high grade B-cell lymphoma with MYC and BCL2 and BCL6 gene rearrangements." These diseases are known colloquially as "double hit" and "triple hit" lymphomas. The "first-hit" in these cases is the harboring of a MYC rearrangement. Concurrent derangements of BCL2 and BCL6 can be the "second-hit" or "third-hit." To our knowledge, this is the first report of "triple-hit" lymphomas in cytology specimens. The files of the Cleveland Clinic (January 2007 through December 2017) were searched for all "triple hit" lymphomas. Four cases met inclusion criteria (cytology slides in files and histologically confirmed "triple hit" lymphoma). All slides were reviewed. The mean age was 65 years, with a male predominance. All patients presented at advanced stage and showed progressive disease despite therapy. FISH studies (histologic sections) confirmed translocations of MYC (8q24), BCL2 (18q21) and BCL6 (3q27) in all patients. All cases were characterized by high cellularity, dispersed cells, presence of stripped nuclei, lymphoglandular bodies, apoptotic bodies, cytomegaly, nucleomegaly, nuclear envelope irregularities, macronucleoli (most often single), recognizable mitoses and presence of cytoplasmic vacuoles (variable). The WHO recommends that all large B-cell lymphomas be investigated using cytogenetic or molecular techniques. Concurrent inhibition of MYC and BCL2 is a potentially effective treatment strategy for triple hit lymphomas, and an expanding literature exists regarding predictive biomarkers and therapeutic regimens. It is our intention to raise awareness of this uncommon mature B-cell neoplasm within the cytodiagnostic community.
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Rearranjo Gênico , Linfoma de Células B/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-myc/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Antígeno Ki-67/metabolismo , Linfoma de Células B/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Biochar produced by pyrolysis of organic residues is increasingly used for soil amendment and many other applications. However, analytical methods for its physical and chemical characterization are yet far from being specifically adapted, optimized, and standardized. Therefore, COST Action TD1107 conducted an interlaboratory comparison in which 22 laboratories from 12 countries analyzed three different types of biochar for 38 physical-chemical parameters (macro- and microelements, heavy metals, polycyclic aromatic hydrocarbons, pH, electrical conductivity, and specific surface area) with their preferential methods. The data were evaluated in detail using professional interlaboratory testing software. Whereas intralaboratory repeatability was generally good or at least acceptable, interlaboratory reproducibility was mostly not (20% < mean reproducibility standard deviation < 460%). This paper contributes to better comparability of biochar data published already and provides recommendations to improve and harmonize specific methods for biochar analysis in the future.
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Carvão Vegetal/análise , Técnicas de Química Analítica/normas , Laboratórios/normas , Técnicas de Química Analítica/instrumentação , Técnicas de Química Analítica/métodos , Padrões de Referência , Reprodutibilidade dos TestesRESUMO
The objective of this work was to investigate the retention mechanisms of ammonium in aqueous solution by using progressively oxidized maple wood biochar at different pH values. Hydrogen peroxide was used to oxidize the biochar to pH values ranging from 8.1 to 3.7, with one set being adjusted to a pH of 7 afterwards. Oxidizing the biochars at their lowered pH did not increase their ability to adsorb ammonium. However, neutralizing the oxygen-containing surface functional groups on oxidized biochar to pH 7 increased ammonia adsorption two to three-fold for biochars originally at pH 3.7-6, but did not change adsorption of biochars oxidized to pH 7 and above. The adsorption characteristics of ammonium are well described by the Freundlich equation. Adsorption was not fully reversible in water, and less than 27% ammonium was desorbed in water in two consecutive steps than previously adsorbed, for biochars with a pH below 7, irrespective of oxidation. Recovery using an extraction with 2M KCl increased from 34% to 99% of ammonium undesorbed by both preceding water extractions with increasing oxidation, largely irrespective of pH adjustment. Unrecovered ammonium in all extractions and residual biochar was negligible at high oxidation, but increased to 39% of initially adsorbed amounts at high pH, likely due to low amounts adsorbed and possible ammonia volatilization losses.
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Acer , Compostos de Amônio/análise , Carvão Vegetal/química , Madeira/química , Adsorção , Poluição Ambiental/prevenção & controle , Concentração de Íons de Hidrogênio , Modelos Teóricos , OxirreduçãoRESUMO
This study underpins quantitative relationships that account for the combined effects that starting biomass and peak pyrolysis temperature have on physico-chemical properties of biochar. Meta-data was assembled from published data of diverse biochar samples (n=102) to (i) obtain networks of intercorrelated properties and (ii) derive models that predict biochar properties. Assembled correlation networks provide a qualitative overview of the combinations of biochar properties likely to occur in a sample. Generalized Linear Models are constructed to account for situations of varying complexity, including: dependence of biochar properties on single or multiple predictor variables, where dependence on multiple variables can have additive and/or interactive effects; non-linear relation between the response and predictors; and non-Gaussian data distributions. The web-tool Biochar Engineering implements the derived models to maximize their utility and distribution. Provided examples illustrate the practical use of the networks, models and web-tool to engineer biochars with prescribed properties desirable for hypothetical scenarios.
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Carvão Vegetal/química , Engenharia/métodos , Biomassa , Intervalos de Confiança , Concentração de Íons de Hidrogênio , Internet , Modelos LinearesRESUMO
Agricultural soils represent the main source of anthropogenic N2O emissions. Recently, interactions of black carbon with the nitrogen cycle have been recognized and the use of biochar is being investigated as a means to reduce N2O emissions. However, the mechanisms of reduction remain unclear. Here we demonstrate the significant impact of biochar on denitrification, with a consistent decrease in N2O emissions by 10-90% in 14 different agricultural soils. Using the (15)N gas-flux method we observed a consistent reduction of the N2O/(N2 + N2O) ratio, which demonstrates that biochar facilitates the last step of denitrification. Biochar acid buffer capacity was identified as an important aspect for mitigation that was not primarily caused by a pH shift in soil. We propose the function of biochar as an "electron shuttle" that facilitates the transfer of electrons to soil denitrifying microorganisms, which together with its liming effect would promote the reduction of N2O to N2.
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Carvão Vegetal/química , Óxido Nitroso/química , Solo/química , Agricultura/métodos , Desnitrificação , Gases/química , Nitrogênio/químicaRESUMO
Biochars (n=94) were found to have ash contents from 0.4% to 88.2%, volatile matter from 13.2% to 70.0%, and fixed carbon from 0% to 77.4% (w/w). Greater pyrolysis temperature for low-ash biochars increased fixed carbon, but decreased it for biochars with more than 20% ash. Nitrogen recovery varied depending on feedstock used to a greater extent (12-68%) than organic (25-45%) or total C (41-76%) at a pyrolysis temperature of 600 °C. Fixed carbon production ranged from no enrichment in poultry biochar to a 10-fold increase in corn biochar (at 600 °C). Prediction of biochar stability was improved by a combination of volatile matter and H:C ratios corrected for inorganic C. In contrast to stability, agronomic utility of biochars is not an absolute value, as it needs to meet local soil constraints. Woody feedstock demonstrated the greatest versatility with pH values ranging from 4 to 9.