Water rock interaction, hydrology and geochemistry of ground and surface waters

Ground and surface waters are essential for human communities and ecosystems. They are complex interconnected systems and are largely controlled by climate and regional geology. The Lawn Hill region, northwest Queensland, Australia is subject to a semi-arid monsoonal climate and is situated on predominantly either carbonate tablelands or plains formed over siliciclastic units. This study analysed rock and water geochemistry, including major and minor elements and stable- and radio-isotopes (3H, 14CDIC¸14CDOC, δ13CDIC, δ13CDOC) and found the following trends of water-rock interaction and flow systems in the region. (1) Groundwater is vital for perennial surface waters. (2) When using chemical tracers to quantify groundwater discharge to surface waters, the volumes could be commonly underestimated if input concentrations are obtained from regional groundwater values, as found for Louie Creek. (3) Host geology is an important control on groundwater flow and chemistry. (4) Groundwaters from carbonate aquifers typically have a chemical composition controlled by dolomite dissolution, they exhibit minimal evapotranspirative enrichment, and have relatively fast recharge (mean residence times were generally <50 a, based on 3H, 14CDIC¸14CDOC analyses). (5) In contrast with carbonate aquifers, groundwaters from siliciclastic aquifers have a chemical composition typically controlled by transpiration, and have highly variable recharge rates but tend to be much slower and older (mean residence times were generally 500-1000s years with minor post-1950 components, based on 3H, 14CDIC¸14CDOC analyses). (6) Radiocarbon analysis of DOC have been rarely applied in Australia and this study highlights the importance of DOC radiocarbon analysis particularly as groundwater residence time estimates from DIC radiocarbon are more error prone in carbonate aquifers

O-antigenic chains of lipopolysaccharide prevent binding of antibody molecules to an outer membrane pore protein in Enterobacteriaceae

The accessibility of outer membrane pore protein PhoE to antibody molecules at the cell surface of intact cells of various Enterobacteriaceae was investigated. Significant antibody binding was observed for only two of the nine strains tested. Analysis of the lipopolysaccharide by sodium dodecyl sulphate gel electrophoresis revealed a clear correlation between the presence of an O-antigenic side chain and the inability to bind PhoE protein-specific antibodies. As mutants that lack the O-antigen chain appeared to have acquired the ability to bind antibody, it must be concluded that the presence of O-antigenic chains of lipopolysaccharide prevents binding of antibodies to PhoE protein at the surface of intact cells. The relevance of this conclusion for the potential use of enterobacterial outer membrane pore proteins as vaccine components is discussed

O Colégio de Aplicação da UFRJ como unidade extensionista: a educação básica na Universidade como espaço de formação e de produção de saberes entre professores

A extensão universitária é um processo educativo, cultural e científico que articula o ensino e a pesquisa. Os Colégios de Aplicação, como unidades de Educação Básica universitárias, devem também ser espaços para o desenvolvimento de atividades extensionistas. Sendo assim, o objetivo deste trabalho é refletir sobre o papel do CAp da UFRJ como espaço produtor de ações de extensão. Para tanto, foram levantadas as ações registradas nos anos de 2012 a 2019. As ações desenvolvidas na escola têm dialogado de forma direta ou indireta com a formação de professores. Recentemente parte das ações passou a integrar o Complexo de Formação de Professores, política universitária que visa repensar a formação docente. Avalia-se, portanto, que a partir das ações desenvolvidas, o CAp cumpre seu papel como unidade de Educação Básica Universitária imbuída da produção de conhecimento e da construção de práticas ligadas à formação docente

A História e os objetivos da Iniciação Científica no Ensino Médio: uma análise a partir dos programas do Estado do Rio de Janeiro

Este trabalho pretende discutir os sentidos da iniciação científica no ensino médio (IC-EM). Considerando a IC-EM como uma experiência em que o aluno tem a possibilidade de vivenciar as etapas do fazer científico, pretendemos discutir os significados formativos dessa atividade. Para tanto, traçamos um histórico do surgimento da IC-EM e analisamos os programas existentes no Estado do Rio de Janeiro. Todos esses programas parecem reproduzir os objetivos da IC feita por alunos de graduação, na medida em que indicam a possibilidade da IC-EM “despertar vocações científicas” e de levar o aluno a vivenciar o fazer científico. Entretanto, esses programas também possuem objetivos próprio, que apontam para o diálogo entre a IC-EM e a melhoria do ensino de ciências; a articulação entre educação básica e o ensino superior e a possibilidade de novas experiências de ensino e aprendizagem no ensino médio. Percebemos que os estudos sobre as especificidades formativas da IC para alunos de ensino médios ainda são escassos e que o maior diálogo entre as instituições de ensino superior e as escolas seria de grande importância para ampliar as potencialidades desses programas

Українська культура як чинник української державності: історичний аспект

У статті подано особливості формування української національної культури кінця XIX - XX століть. Охарактеризовано розвиток культури за умови становлення української державності. Автор намагався простежити вплив національного суспільства на розвиток культури в конкретний історичний період.The article introduces the features of formation of the Ukrainian national culture of the 19th-20th centuries. Characterized by the development of culture during becoming of Ukrainian statehood. The author tried to trace the influence of the national society for the development of culture in a specific historical period

Vitamin D concentration and psychotic disorder:associations with disease status, clinical variables and urbanicity

Background The association between schizophrenia and decreased vitamin D levels is well documented. Low maternal and postnatal vitamin D levels suggest a possible etiological mechanism. Alternatively, vitamin D deficiency in patients with schizophrenia is presumably (also) the result of disease-related factors or demographic risk factors such as urbanicity. Methods In a study population of 347 patients with psychotic disorder and 282 controls, group differences in vitamin D concentration were examined. Within the patient group, associations between vitamin D, symptom levels and clinical variables were analyzed. Group x urbanicity interactions in the model of vitamin D concentration were examined. Both current urbanicity and urbanicity at birth were assessed. Results Vitamin D concentrations were significantly lower in patients (B= -8.05; 95% confidence interval (CI) -13.68 to -2.42;p= 0.005). In patients, higher vitamin D concentration was associated with lower positive (B= -0.02; 95% CI -0.04 to 0.00;p= 0.049) and negative symptom levels (B= -0.03; 95% CI -0.05 to -0.01;p= 0.008). Group differences were moderated by urbanicity at birth (chi(2)= 6.76 andp= 0.001), but not by current urbanicity (chi(2)= 1.50 andp= 0.224). Urbanicity at birth was negatively associated with vitamin D concentration in patients (B= -5.11; 95% CI -9.41 to -0.81;p= 0.020), but not in controls (B= 0.72; 95% CI -4.02 to 5.46;p= 0.765). Conclusions Lower vitamin D levels in patients with psychotic disorder may in part reflect the effect of psychosis risk mediated by early environmental adversity. The data also suggest that lower vitamin D and psychopathology may be related through direct or indirect mechanisms.</p

In matrix derivatization combined with LC-MS/MS results in ultra-sensitive quantification of plasma free metanephrines and catecholamines

Plasma-free metanephrines and catecholamines are essential markers in the biochemical diagnosis and follow-up of neuroendocrine tumors and inborn errors of metabolism. However, their low circulating concentrations (in the nanomolar range) and poor fragmentation characteristics hinder facile simultaneous quantification by liquid chromatography and tandem mass spectrometry (LC-MS/MS). Here, we present a sensitive and simple matrix derivatization procedure using propionic anhydride that enables simultaneous quantification of unconjugated l-DOPA, catecholamines, and metanephrines in plasma by LC-MS/MS. Dilution of propionic anhydride 1:4 (v/v) in acetonitrile in combination with 50 μL of plasma resulted in the highest mass spectrometric response. In plasma, derivatization resulted in stable derivatives and increased sensitivity by a factor of 4-30 compared with a previous LC-MS/MS method for measuring plasma metanephrines in our laboratory. Furthermore, propionylation increased specificity, especially for 3-methoxytyramine, by preventing interference from antihypertensive medication (β-blockers). The method was validated according to international guidelines and correlated with a hydrophilic interaction LC-MS/MS method for measuring plasma metanephrines (R2 > 0.99) and high-performance liquid chromatography with an electrochemical detection method for measuring plasma catecholamines (R2 > 0.85). Reference intervals for l-DOPA, catecholamines, and metanephrines in n = 115 healthy individuals were established. Our work shows that analytes in the subnanomolar range in plasma can be derivatized in situ without any preceding sample extraction. The developed method shows improved sensitivity and selectivity over existing methods and enables simultaneous quantification of several classes of amines

Production of bacterial outer membrane vesicles as vaccine platform

Bacterial outer membrane vesicles (OMVs) are non-infectious but highly immunogenic particles. These vesicles are used as vaccines against the disease of the source bacteria. Fascinatingly, the addition of heterologous antigens to these vesicles creates a versatile vaccine platform. Such a platform can be used as an alternative to subunit vaccines, during infectious disease outbreaks or for the development of vaccines against pathogens that require high containment. A unique aspect of this platform is the reusability of the production process for many different vaccines. This in turn could reduce the time to market for new vaccines significantly. We designed a heterologous OMV vaccine concept for Lyme disease based on spontaneous released OMVs from Neisseria meningitidis that express the Outer surface protein A (OspA) of Borrelia burgdorferi on the surface. The productivity of spontaneously released OMVs was improved by the introduction of oxidative stress to the bacterial culture. Increased dissolved oxygen concentrations during cultivation showed to be an excellent process parameter for enhanced release of OMVs, while the bacterial culture remains viable. This presentation will cover the development of the OMV-based vaccine platform and the impact of changes in the upstream process on the downstream process of the investigational OMV-based Lyme disease vaccine. Please click Additional Files below to see the full abstract

Substrate specificity of the pyrophosphohydrolase LpxH determines the asymmetry of Bordetella pertussis lipid A

Lipopolysaccharides are anchored to the outer membrane of Gram-negative bacteria by a hydrophobic moiety known as lipid A, which potently activates the host innate immune response. Lipid A of Bordetella pertussis, the causative agent of whooping cough, displays unusual structural asymmetry with respect to the length of the acyl chains at the 3 and 3′ positions, which are 3OH-C10 and 3OH-C14 chains, respectively. Both chains are attached by the acyltransferase LpxA, the first enzyme in the lipid A biosynthesis pathway, which, in B. pertussis, has limited chain length specificity. However, this only partially explains the strict asymmetry of lipid A. In attempts to modulate the endotoxicity of B. pertussis lipid A, here we expressed the gene encoding LpxA from Neisseria meningitidis, which specifically attaches 3OH-C12 chains, in B. pertussis. This expression was lethal, suggesting that one of the downstream enzymes in the lipid A biosynthesis pathway in B. pertussis cannot handle precursors with a 3OH-C12 chain. We considered that the UDP-diacylglucosamine pyrophosphohydrolase LpxH could be responsible for this defect as well as for the asymmetry of B. pertussis lipid A. Expression of meningococcal LpxH in B. pertussis indeed resulted in new symmetric lipid A species with 3OH-C10 or 3OH-C14 chains at both the 3 and 3′ positions, as revealed by MS analysis. Furthermore, co-expression of meningococcal lpxH and lpxA resulted in viable cells that incorporated 3OH-C12 chains in B. pertussis lipid A. We conclude that the asymmetry of B. pertussis lipid A is determined by the acyl chain length specificity of LpxH