DODAB and DODAC bilayer-like aggregates in the micromolar surfactant concentration domain

In the millimolar concentration domain (typically 1 mM), dioctadecyldimethylammonium bromide and chloride (DODAX, X representing Br- or Cl- counterions) molecules assemble in water as large unilamellar vesicles. Differential scanning calorimetry (DSC) is a suitable technique to obtain the melting temperature (Tm) characteristic of surfactant bilayers, while fluorescence spectroscopy detects formation of surfactant aggregates, like bilayers. These two techniques were combined to investigate the assemble of DODAX molecules at micromolar concentrations, from 10 to 100 micromolar. At 1 mM surfactant, Tm ~ 45 ºC and 49 oC, respectively for DODAB and DODAC. DSC and fluorescence of Nile Red were used to show the formation of DODAX aggregates, at the surfactant concentration as low as 10 micromolar, whose Tm decreases monotonically with increasing DODAX concentration to attain the value for the ordinary vesicles. The data indicate that these aggregates are organized as bilayer-like structures.Fundação para a Ciência e a Tecnologia (FCT

Life history and chemical ecology of the Warrior wasp Synoeca septentrionalis (Hymenoptera : Vespidae, Epiponini)

Swarm-founding ‘Warrior wasps’ (Synoeca spp.) are found throughout the tropical regions of South America, are much feared due to their aggressive nest defence and painful sting. There are only five species of Synoeca, all construct distinctive nests that consist of a single sessile comb built onto the surface of a tree or rock face, which is covered by a ribbed envelope. Although locally common, research into this group is just starting. We studied eight colonies of Synoeca septentrionalis, a species recently been described from Brazil. A new colony is established by a swarm of 52 to 140 adults that constructs a colony containing around 200 brood cells. The largest colony collected containing 865 adults and over 1400 cells. The number of queen’s present among the eight colonies varied between 3 and 58 and no clear association between colony development and queen number was detected. Workers and queens were morphologically indistinguishable, but differences in their cuticular hydrocarbons were detected, particularly in their (Z)-9-alkenes. The simple cuticular profile, multiple queens, large size and small number of species makes the ‘Warrior wasps’ an excellent model group for further chemical ecology studies of swarm-founding wasps

Synthesis and Anti-Mycobacterium tuberculosis Activity of Imidazo[2,1-b][1,3]oxazine Derivatives against Multidrug-Resistant Strains

The emergence of multidrug-resistant strains of M. tuberculosis has raised concerns due to the greater difficulties in patient treatment and higher mortality rates. Herein, we revisited the 2-nitro-6,7-dihydro-5H-imidazo[2,1-b][1,3]oxazine scaffold and identified potent new carbamate derivatives having MIC90 values of 0.18–1.63 μM against Mtb H37Rv. Compounds 47–49, 51–53, and 55 exhibited remarkable activity against a panel of clinical isolates, displaying MIC90 values below 0.5 μM. In Mtb-infected macrophages, several compounds demonstrated a 1-log greater reduction in mycobacterial burden than rifampicin and pretomanid. The compounds tested did not exhibit significant cytotoxicity against three cell lines or any toxicity to Galleria mellonella. Furthermore, the imidazo[2,1-b][1,3]oxazine derivatives did not show substantial activity against other bacteria or fungi. Finally, molecular docking studies revealed that the new compounds could interact with the deazaflavin-dependent nitroreductase (Ddn) in a similar manner to pretomanid. Collectively, our findings highlight the chemical universe of imidazo[2,1-b][1,3]oxazines and their promising potential against MDR-TB

Dimensão pessoal do processo de trabalho para enfermeiras de Unidades de Terapia Intensiva

OBJETIVO: Compreender os aspectos da dimensão pessoal do processo de trabalho para enfermeiras que atuam em Unidades de Terapia Intensiva (UTI) de um hospital universitário do interior do Estado de São Paulo. MÉTODOS: Estudo de abordagem qualitativa utilizando o método fenomenológico. Foram entrevistadas 12 enfermeiras que trabalhavam nas UTI de adulto, pediátrica e coronariana dessa instituição hospitalar e para análise dos relatos, utilizou-se o referencial da estrutura do fenômeno situado. RESULTADOS: A análise dos relatos permitiu identificar a categoria: dimensão pessoal do trabalho na UTI, com os temas - trabalho gratificante, trabalho desgastante e (des) valorização do trabalho. CONCLUSÃO: Os resultados do estudo revelam que as enfermeiras das UTI selecionadas identificam-se com o trabalho, porém vivenciam situações desmotivadoras decorrentes da elevada carga de trabalho, que dificulta o desenvolvimento do processo de trabalho e compromete a qualidade do cuidado.OBJETIVO: Comprender los aspectos de la dimensión personal del proceso de trabajo para enfermeras que actúan en Unidades de Cuidados Intensivos (UCI) de un hospital universitario del interior del Estado de Sao Paulo. MÉTODOS: Se trata de un estudio con abordaje cualitativo en el que se usó el método fenomenológico. Se entrevistaron a 12 enfermeras que trabajaban en las UCI de adulto, pediátrica y coronaria de esa institución hospitalaria y para el análisis de los relatos, se consideró el referencial de la estructura del fenómeno situado. RESULTADOS: El análisis de los relatos permitió identificar la categoría: dimensión personal del trabajo en la UCI, con los temas - trabajo gratificante, trabajo desgastante y (des) valorización del trabajo. CONCLUSIÓN: Los resultados del estudio revelan que las enfermeras de las UCI seleccionadas se identifican con el trabajo, no obstante vivencian situaciones desmotivadoras como consecuencia de la elevada carga de trabajo, que dificulta el desarrollo del proceso de trabajo y compromete la calidad del cuidado.OBJECTIVE: To understand the personal dimension of the work process for nurses working in intensive care units (ICU) of a university hospital in the state of São Paulo. METHODS: A qualitative study using the phenomenological method. We interviewed 12 nurses working in adult, pediatric and coronary ICUs in this hospital; to analyze results, we used the phenomenonogical method. RESULTS: The analysis of the results identified the category, personal dimension of ICU work, which included the themes, "rewarding work", "exhausting work", and, "lack of appreciation of the work". CONCLUSION: The results of this study revealed that the ICU nurses interviewed identified with their work, but that they experience discouraging situations resulting from high workload, which hinders the development of the work process and compromises the quality of care

Monitoring of metals, organic compounds and coliforms in water catchment points from the Sinos River basin

&lt;p&gt;Unplanned use and occupation of the land without respecting its capacity of assimilation and environmental purification leads to the degradation of the environment and of water used for human consumption. Agricultural areas, industrial plants and urban centres developed without planning and the control of effluent discharges are the main causes of water pollution in river basins that receive all the liquid effluents produced in those places. Over the last decades, environmental management has become part of governmental agendas in search of solutions for the preservation of water quality and the restoration of already degraded resources. This study evaluated the conditions of the main watercourse of the Sinos River basin by monitoring the main physical, chemical and microbiological parameters described in the CONAMA Resolution no. 357/2005.The set of parameters evaluated at five catchment points of water human consumption revealed a river that has different characteristics in each reach, as the upper reach was class 1, whereas the middle and lower reaches of the basin were class 4. Monitoring pointed to households as the main sources of pollutants in those reaches, although metals used in the industrial production of the region were found in the samples analyzed.&lt;/p&gt;</jats:p

Response of foundation macrophytes to near‐natural simulated marine heatwaves

Marine heatwaves have been observed worldwide and are expected to increase in both frequency and intensity due to climate change. Such events may cause ecosystem reconfigurations arising from species range contraction or redistribution, with ecological, economic and social implications. Macrophytes such as the brown seaweed Fucus vesiculosus and the seagrass Zostera marina are foundation species in many coastal ecosystems of the temperate northern hemisphere. Hence, their response to extreme events can potentially determine the fate of associated ecosystems. Macrophyte functioning is intimately linked to the maintenance of photosynthesis, growth and reproduction, and resistance against pathogens, epibionts and grazers. We investigated morphological, physiological, pathological and chemical defence responses of western Baltic Sea F. vesiculosus and Z. marina populations to simulated near‐natural marine heatwaves. Along with (a) the control, which constituted no heatwave but natural stochastic temperature variability (0HW), two treatments were applied: (b) two late‐spring heatwaves (June, July) followed by a summer heatwave (August; 3HW) and (c) a summer heatwave only (1HW). The 3HW treatment was applied to test whether preconditioning events can modulate the potential sensitivity to the summer heatwave. Despite the variety of responses measured in both species, only Z. marina growth was impaired by the accumulative heat stress imposed by the 3HW treatment. Photosynthetic rate, however, remained high after the last heatwave indicating potential for recovery. Only epibacterial abundance was significantly affected in F. vesiculosus. Hence both macrophytes, and in particular F. vesiculosus, seem to be fairly tolerant to short‐term marine heatwaves at least at the intensities applied in this experiment (up to 5°C above mean temperature over a period of 9 days). This may partly be due to the fact that F. vesiculosus grows in a highly variable environment, and may have a high phenotypic plasticit

Agronomic performance of sweet potato with different potassium fertilization rates

ABSTRACT Sweet potato is a vegetable with great potential due to its versatility of use, which covers human food, animal feed and biofuels. However, it is still little studied, especially regarding mineral nutrition and potassium. Thus, a study was conducted to evaluate potassium fertilizer doses (0, 30, 60, 90, 120 and 150 kg/ha K2O) on mineral nutrition and yield of 'Beauregard' sweet potato in a typic Hapludult soil with low K level (0.3 mmolc/dm3). The experimental design was of randomized blocks with four repetitions. Harvest took place 123 days after seedling transplanting. Foliar K content, shoot, root and total dry matter, root total yield, root commercial yield, K accumulation, K content in the soil and K optimal economic dose were assessed. The highest foliar K content was observed at the dose of 100 kg/ha K2O, with K value of 44.6 g/kg on leaf dry matter. In soils with low K availability, the highest yield (38 t/ha) was observed at the dose of 87 kg/ha K2O. Maximum commercial yield (24.3 t/ha) was obtained at the dose of 85 kg/ha K2O, and K accumulation of 150 kg/ha in the shoot and 57 kg/ha in the root, respectively, were observed (72.5 and 27.5%). Optimal economic production was of 71 kg/ha K2O, which corresponds to 83% of the dose that maximized commercial production

“Se viveres como louco, sabes que hás de morrer sem juízo”: as orientações para o bem morrer na literatura cristã portuguesa do século XVIII

Resumo Orientar os fiéis para uma vida santificada e instruí-los para uma boa morte foram objetivos muito comuns na literatura religiosa portuguesa do período moderno, especialmente aquela divulgada no século XVIII e que se propunha a definir e propagar virtudes morais e comportamentos que garantissem o bem morrer. Nosso objetivo, neste artigo, é o de analisar as orientações que todo fiel católico deveria observar como preparação prévia para a morte nas obras Sermão da Missão da quarta tarde da quaresma (1734), Terceiro Instruído na Virtude (1742) e Mestre da Virtude(1745), produzidas pelo padre dominicano português João Franc

Expression in Antennae and Reproductive Organs Suggests a Dual Role of an Odorant-Binding Protein in Two Sibling Helicoverpa Species

Odorant-binding proteins (OBPs) mediate both perception and release of semiochemicals in insects. These proteins are the ideal targets for understanding the olfactory code of insects as well as for interfering with their communication system in order to control pest species. The two sibling Lepidopteran species Helicoverpa armigera and H. assulta are two major agricultural pests. As part of our aim to characterize the OBP repertoire of these two species, here we focus our attention on a member of this family, OBP10, particularly interesting for its expression pattern. The protein is specifically expressed in the antennae of both sexes, being absent from other sensory organs. However, it is highly abundant in seminal fluid, is transferred to females during mating and is eventually found on the surface of fertilised eggs. Among the several different volatile compounds present in reproductive organs, OBP10 binds 1-dodecene, a compound reported as an insect repellent. These results have been verified in both H. armigera and H. assulta with no apparent differences between the two species. The recombinant OBP10 binds, besides 1-dodecene, some linear alcohols and several aromatic compounds. The structural similarity of OBP10 with OBP1 of the mosquito Culex quinquefasciatus, a protein reported to bind an oviposition pheromone, and its affinity with 1-dodecene suggest that OBP10 could be a carrier for oviposition deterrents, favouring spreading of the eggs in these species where cannibalism is active among larvae