Influence of Pyrolysis Parameters on the Performance of CMSM

Carbon hollow fiber membranes have been prepared by pyrolysis of a P84/S-PEEK blend. Proximate analysis of the precursor was performed using thermogravimetry (TGA), and a carbon yield of approximately 40% can be obtained. This study aimed at understanding the influence of pyrolysis parameters—end temperature, quenching effect, and soaking time—on the membrane properties. Permeation experiments were performed with N2, He, and CO2. Scanning electron microscopy (SEM) has been done for all carbon hollow fibers. The highest permeances were obtained for the membrane submitted to an end temperature of 750°C and the highest ideal selectivities for an end temperature of 700°C. In both cases, the membranes were quenched to room temperatur

Crosstalk between ROS Homeostasis and Secondary Metabolism in S. natalensis ATCC 27448: Modulation of Pimaricin Production by Intracellular ROS

Streptomyces secondary metabolism is strongly affected by oxygen availability. The increased culture aeration enhances pimaricin production in S. natalensis, however the excess of O2 consumption can lead to an intracellular ROS imbalance that is harmful to the cell. The adaptive physiological response of S. natalensis upon the addition of exogenous H2O2 suggested that the modulation of the intracellular ROS levels, through the activation of the H2O2 inducible catalase during the late exponential growth phase, can alter the production of pimaricin. With the construction of defective mutants on the H2O2 related enzymes SodF, AhpCD and KatA1, an effective and enduring modulation of intracellular ROS was achieved. Characterization of the knock-out strains revealed different behaviours regarding pimaricin production: whilst the superoxide dismutase defective mutant presented low levels of pimaricin production compared to the wild-type, the mutants defective on the H2O2-detoxifying enzymes displayed a pimaricin overproducer phenotype. Using physiological and molecular approaches we report a crosstalk between oxidative stress and secondary metabolism regulatory networks. Our results reveal that the redox-based regulation network triggered by an imbalance of the intracellular ROS homeostasis is also able to modulate the biosynthesis of pimaricin in S. natalensis

A Simple in situ Assay to Assess Plant-Associative Bacterial Nitrogenase Activity

Assessment of plant-associative bacterial nitrogen (N) fixation is crucial for selection and development of elite diazotrophic inoculants that could be used to supply cereal crops with nitrogen in a sustainable manner. Although diazotrophic bacteria possess diverse oxygen tolerance mechanisms, most require a sub 21% oxygen environment to achieve optimal stability and function of the N-fixing catalyst nitrogenase. Consequently, assessment of N fixation is routinely carried out on “free-living” bacteria grown in the absence of a host plant and such experiments may not accurately divulge activity in the rhizosphere where the availability and forms of nutrients such as carbon and N, which are key regulators of N fixation, may vary widely. Here, we present a modified in situ acetylene reduction assay (ARA), utilizing the model cereal barley as a host to comparatively assess nitrogenase activity in diazotrophic bacteria. The assay is rapid, highly reproducible, applicable to a broad range of diazotrophs, and can be performed with simple equipment commonly found in most laboratories that investigate plant-microbe interactions. Thus, the assay could serve as a first point of order for high-throughput identification of elite plant-associative diazotrophs

Avaliação dos fatores que influenciam na ocorrência e na concentração das populações de protozoários ciliados (Protista, Ciliophora) do rúmen de ovinos (Ovis Aries L.) mantidos em pastagens naturais no semi-árido de Pernambuco, Brasil

-No Brasil são escassos os estudos sobre morfologia de protozoários ciliados no rúmen de animais domésticos, principalmente em hospedeiros ovinos. O gênero Metadinium Awerinzew & Mutafowa, 1914 compreende atualmente 13 espécies registradas em diversos hospedeiros. Este trabalho teve como objetivo estudar ciliados do rúmen e caracterizar morfologicamente duas espécies do gênero Metadinium, identificadas como Metadinium cf. ossiculi e Metadinium cf. esalqum, em ovinos mestiços Santa Inês mantidos extensivamente em pastagens naturais de caatinga. Foram realizadas análises morfométricas em 30 indivíduos de cada espécie. A população de Metadinium cf. ossiculi apresentou os seguintes valores em micrômetros (mm): 94,4 (76-156) de comprimento total; 56,10 (47-89) de largura; 61,45 de comprimento total da placa; 21,07 de largura total da placa; 33,76 de comprimento total do braço direito; 33,37 de comprimento total do braço esquerdo; 26,71 de distância da extremidade posterior ao ponto de fusão e 10,80 de largura da placa no ponto de fusão dos braços; presença de um lobo na extremidade posterior do corpo e macronúcleo em forma de bastão com a extremidade anterior arredondada. A população de Metadinium cf. esalqum apresentou os seguintes valores: 94,60 (65-186) de comprimento total; 63,20 (46-120) de largura total; 74,30 de comprimento total da placa; 29,55 de largura total da placa; 32,12 de comprimento total do braço direito; 30,76 de comprimento total do braço esquerdo; 42,55 de distância da extremidade posterior ao ponto de fusão e 22,28 de largura da placa no ponto de fusão dos braços; usência de lobo e macronúcleo em forma de F invertido. As duas espécies apresentaram semelhança quanto ao comprimento e à largura do corpo, mas diferiram quanto a morfometria e morfologia das placas esqueléticas, e quanto à forma do macronúcleo. Atributos da morfologia e morfometria da placa esquelética foram sugeridos para se ampliar os caracteres diagnósticos das espécies do gênero Metadinium, táxon este que necessita de revisão taxonômica e de re-descrições de espécies utilizando-se técnicas modernas em ciliatologia. A determinação específica é de fundamental importância para o conhecimento acerca do papel que esses protozoários desempenham no organismo do hospedeiro. O presente trabalho faz o primeiro registro de espécies do gênero Metadinium em ovinos no Brasil e amplia a descrição das espécies M. cf. ossiculi e M. cf. esalqum, com a introdução de novos parâmetros para estudos de taxonomia e morfologia do grupo

Death ideation in cancer patients: contributing factors

Advances in cancer research and therapy have improved prognosis and the quality of life of many patients. However, previous epidemiological studies in oncologic patients have shown an increased risk of suicide. Suicidal thoughts, relatively well known in those terminally ill, may be just as important for cancer patients who are survivors or are living with the disease. Nonetheless, there is a relative paucity of data about suicidality in this setting. The authors conducted a prospective observational study to identify death thoughts and to explore the factors associated with suicidal ideation in cancer patients. A sample of 130 patients referred for psychiatric consultation was obtained following informed consent and authorization from the local ethics committee. A semistructured interview assessed sociodemographic data, psychosocial support, and information regarding the cancer process and its treatment. Psychometric instruments were used to evaluate psychopathology, namely the Hospital Anxiety and Depression Scale, the Beck Hopelessness Scale, and the Beck Scale for Suicide Ideation. Psychiatric diagnoses were obtained through the application of the Mini International Neuropsychiatric Interview. Death ideation was identified in 34.6% of patients, yet only 10% had active suicidal thoughts. Risk of suicide was associated with female gender, a psychiatric diagnosis (major depressive disorder, panic disorder, or dysthymia), difficult interpersonal relationships, associated pain, high hopelessness, and depressive and anxiety symptoms. Although suicidal thoughts are frequent in cancer patients at different stages of disease, most are transitory. Risk factors for suicidal ideation have been identified, such as depression, hopelessness, uncontrolled pain, and difficult interpersonal relationships. Further assessment is necessary to identify those at higher risk of attempting suicide, and underlying psychiatric disorders should be vigorously treated

The view of teachers on bullying and implications for nursing

Objetivo: Compreender o bullying escolar, na perspectiva dos professores, e refletir sobre as possíveis ações da área da saúde em seu enfrentamento. Para tanto, tomaram- se por base as diretrizes do Programa Saúde na Escola, dos Ministérios da Saúde e da Educação. Método: Estudo de caso qualitativo, realizado com professores de uma escola pública de Minas Gerais. Foram utilizados grupos focais na coleta de dados e o material empírico foi decodificado a partir de técnica de análise temática de conteúdo, resultando em uma categoria analítica: concepções e experiências de professores diante do bullying. Resultados: Foram identificadas percepções pontuais sobre o fenômeno e utilização de recursos de intervenção pouco eficazes. No plano interpretativo, problematizaram-se as contribuições da saúde e da enfermagem no redimensionamento das intervenções e no processo de formação continuada dos professores. Conclusão: Os resultados apontam para a construção de práticas intersetoriais para o enfrentamento do bullying.To understand school bullying from the perspective of teachers and reflect about the possible actions of the health area when coping with it. The guidelines of the School Health Program of the Ministries of Health and Education were used to reach that purpose. Method: A qualitative study carried out with teachers of a public school in Minas Gerais. Focus groups were used to collect data and the empirical material was decoded from thematic analysis of content, resulting in an analytical category: conceptions and experiences of teachers on bullying. Results: Specific perceptions about the phenomenon and the use of ineffective intervention resources were identified. In the interpretive plan were problematized the health and nursing contributions with resizing the interventions and the continuing training process of teachers. Conclusion: The results point to the construction of intersectoral practices forcoping with bullying.Objetivo: Comprender el bullying escolar desde la perspectiva de los profesores, y reflexionar sobre las posibles acciones del área de salud en su enfrentamiento. Tomando como base los lineamientos del Programa de Salud Escolar, de los Ministerios de Salud y de Educación. Método: Estudio de caso cualitativo realizado con los profesores de una escuela pública en Minas Gerais. Para la recolección de datos se utilizaron grupos focales y el material empírico fue decodificado a partir de la técnica de análisis temático de contenido, dando lugar a una categoría analítica: concepciones y experiencias de los profesores sobre el acoso escolar. Resultados: Se identificaron percepciones específicas sobre el fenómeno y la utilización de recursos ineficaces de intervención. En el plano interpretativo, se problematizaron las contribuciones de la salud y de la enfermería en el redimensionamiento de las intervenciones y en el proceso de formación continua de los profesores. Conclusión: Los resultados apuntan a la construcción de prácticas intersectoriales para el enfrentamiento del bullying.CIEC - Centro de Investigação em Estudos da Criança, UM (UI 317 da FCT