24 research outputs found

    Engineering aspects of hydrothermal pretreatment: from batch to continuous operation, scale-up and pilot reactor under biorefinery concept

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    Different pretreatments strategies have been developed over the years mainly to enhance enzymatic cellulose degradation. In the new biorefinery era, a more holistic view on pretreatment is required to secure optimal use of the whole biomass. Hydrothermal pretreatment technology is regarded as very promising for lignocellulose biomass fractionation biorefinery and to be implemented at the industrial scale for biorefineries of second generation and circular bioeconomy, since it does not require no chemical inputs other than liquid water or steam and heat. This review focuses on the fundamentals of hydrothermal pretreatment, structure changes of biomass during this pretreatment, multiproduct strategies in terms of biorefinery, reactor technology and engineering aspects from batch to continuous operation. The treatise includes a case study of hydrothermal biomass pretreatment at pilot plant scale and integrated process design.The authors gratefully thank the Secretary of Public Education ofMexico – Mexican Science and Technology Council (SEP-CONACYT,Mexico) for the Basic Science Project -2015-01 (Ref. 254808), EnergySustainability Fund 2014-05 (CONACYT-SENER), Mexican Centre forInnovation in Bioenergy (Cemie-Bio), Cluster of Bioalcohols (Ref.249564) and the BMBF for the financial support (reference number:031B0660A).info:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Freqüência da doença celáaca e seus marcadores sorológicos em pacientes com hepatite auto-imune

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    Transglutaminase (anti-tTG) and anti-endomysial (AEA) antibodies were reported to occur in patients with autoimmune hepatitis (AIH) as well as in subjects with advanced cirrhosis, but the prevalence of celiac disease (CD) in patients with AIH is either negligible or unknown. The frequency of IgA anti-tTG and IgA AEA was determined in 64 patients (54 females, mean age 19[5-67] years ) with AIH diagnosed according to international criteria. Patients with positive or intermediate results for those antibodies were submitted to duodenal biopsy and HLA-DQ2 or DQ8 typing. Anti-tTG and AEA were detected in 6 (9%) and one patient (1.6%) with AIH, respectively. Positive and borderline results for IgA anti-tTG were detected, respectively, in two (3%) and four (6%) patients. Only one patient with HLA-DQ2 and IgA anti-tTG and IgA AEA had CD on duodenal biopsy. Two patients with either positive or borderline results for IgA anti-tTG antibody and HLA-DQ2 had normal histology on duodenal biopsy. IgA anti-tTG antibody and/or AEA were observed in 9% of AIH patients, but CD was confirmed in only one of them. The occurrence of IgA anti-tTG antibody in the other patients could be ascribed to the presence of chronic liver disease or to latent or potential CD.Anticorpos antitransglutaminase (anti-TGt) e antiendomísio (AAE) são identificados em pacientes com hepatite auto-imune (HAI), assim como em pacientes com cirrose avançada. Contudo, a prevalência de doença celíaca (DC) em pacientes de HAI é desconhecida. A freqüência de anti-TGt IgA e AAE IgA foi determinada em 64 pacientes (54 mulheres,com media de idade de 19 anos [5-67]) com diagnóstico de HAI definido pelos critérios internacionais de HAI. Os pacientes anti-TGt IgA positive ou indeterminado e (ou) AAE IgA positivo foram submetidos à biópsia duodenal e determinou-se o tipo de HLA-DQ2 ou DQ8. Os anticorpos anti-TGt  IgA e AAE IgA foram observados em 6 (9%) pacientes e em um paciente (1,6%) com HAI, respectivamente. Resultados positivos e borderline para anti-TGt IgA foram encontrados, respectivamente, em dois pacientes (3%) e quatro pacientes (6%). A DC foi confirmada pela biópsia duodenal (Marsh 3b) em um paciente com HLA-DQ2, anti-TGt IgA e AAE IgA. Outros dois pacientes apresentaram anti-TGt positivo ou bordeline e HLA DQ2 e a histologia duodenal mostrou-se sem alterações. Positividade para anticorpos anti-TGt IgA e (ou) AAE IgA foi observada em 9% dos pacientes com hepatite auto-imune, porém o diagnóstico foi confirmado em apenas um dos pacientes (1,6%). A ocorrência de anticorpo anti-TGt IgA nos outros pacientes pode ser atribuída à presença de doença hepática crônica, ou, ainda,a  uma DC latente ou um paciente com potencial para DC
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