Photosynthesis in estuarine intertidal microphytobenthos is limited by inorganic carbon availability.

The effects of dissolved inorganic carbon (DIC) availability on photosynthesis were studied in two estuarine intertidal microphytobenthos (MPB) communities and in the model diatom species Phaeodactylum tricornutum. Kinetics of DIC acquisition, measured with a liquid-phase oxygen electrode, showed higher K(1/2)(DIC) (0.31 mM) and Vm (7.78 nmol min(-1) µg (Chl a)(-1)) for MPB suspensions than for P. tricornutum (K(1/2)(DIC) = 0.23 mM; Vm = 4.64 nmol min(-1) µg (Chl a)(-1)), suggesting the predominance of species with lower affinity for DIC and higher photosynthetic capacity in the MPB. The net photosynthetic rate of the MPB suspensions reached saturation at a DIC concentration of 1-1.5 mM. This range was lower than the concentrations found in the interstitial water of the top 5-mm sediment layer, suggesting no limitation of photosynthesis by DIC in the MPB communities. Accordingly, carbon isotope discrimination revealed a moderate activity of CO2-concentrating mechanisms in the MPB. However, addition of NaHCO3 to intact MPB biofilms caused a significant increase in the relative maximum photosynthetic electron transport rate (rETR max) measured by imaging pulse-amplitude modulated chlorophyll a fluorescence. These results suggest local depletion of DIC at the photic layer of the sediment (the first few hundred µm), where MPB cells accumulate during diurnal low tides. This work provides the first direct experimental evidence of DIC limitation of photosynthesis in highly productive intertidal MPB communities.

Effects of elevated temperature and CO2 on intertidal microphytobenthos.

BACKGROUND: Microphytobenthos (MPB) are the main primary producers of many intertidal and shallow subtidal environments. Although these coastal ecosystems are particularly vulnerable to anthropogenic activities, little is known on the effects of climate change variables on the structure and productivity of MPB communities. In this study, the effects of elevated temperature and CO2 on intertidal MPB biomass, species composition and photosynthetic performance were studied using a flow-through experimental life support system. RESULTS: Elevated temperature had a detrimental effect on MPB biomass and photosynthetic performance under both control and elevated CO2. Furthermore, elevated temperature led to an increase of cyanobacteria and a change in the relative abundance of major benthic diatom species present in the MPB community. The most abundant motile epipelic species Navicula spartinetensis and Gyrosigma acuminatum were in part replaced by tychoplanktonic species (Minidiscus chilensis and Thalassiosira cf. pseudonana) and the motile epipelic Nitzschia cf. aequorea and N. cf. aurariae. Elevated CO2 had a beneficial effect on MPB biomass, but only at the lower temperature. It is possible that elevated CO2 alleviated local depletion of dissolved inorganic carbon resulting from high cell abundance at the sediment photic layer. No significant effect of elevated CO2 was detected on the relative abundance of major groups of microalgae and benthic diatom species. CONCLUSIONS: The interactive effects of elevated temperature and CO2 may have an overall detrimental impact on the structure and productivity of intertidal MPB, and eventually in related ecosystem services.

Mapping grape berry photosynthesis by chlorophyll fluorescence imaging: the effect of saturating pulse intensity in different tissues.

Grape berry development and ripening depends mainly on imported photosynthates from leaves, however, fruit photosynthesis may also contribute to the carbon economy of the fruit. In this study pulse amplitude modulated chlorophyll fluorescence imaging (imaging-PAM) was used to assess photosynthetic properties of tissues of green grape berries. In particular, the effect of the saturation pulse (SP) intensity was investigated. A clear tissue-specific distribution pattern of photosynthetic competence was observed. The exocarp revealed the highest photosynthetic capacity and the lowest susceptibility to photoinhibition, and the mesocarp exhibited very low fluorescence signals and photochemical competence. Remarkably, the seed outer integument revealed a photosynthetic ability similar to that of the exocarp. At a SP intensity of 5000 µmol m(-2) s(-1) several photochemical parameters were decreased, including maximum fluorescence in dark-adapted (F(m)) and light-adapted (F'(m)) samples and effective quantum yield of PSII (Φ(II)), but the inner tissues were susceptible to a SP intensity as low as 3200 µmol m(-2) s(-1) under light-adapted conditions, indicating a photoinhibitory interaction between SP and actinic light intensities and repetitive exposure to SP. These results open the way to further studies concerning the involvement of tissue-specific photosynthesis in the highly compartmentalized production and accumulation of organic compounds during grape berry development.

Photosynthesis assessment in microphytobenthos using conventional and imaging pulse amplitude modulation fluorometry.

Imaging pulse amplitude modulated (Imaging-PAM) fluorometry is a breakthrough in the study of spatial heterogeneity of photosynthetic assemblages. However, Imaging and conventional PAM uses a different technology, making comparisons between these techniques doubtful. Thereby, photosynthetic processes were comparatively assessed using conventional (Junior PAM and PAM 101) and Imaging-PAM on intertidal microphytobenthos (MPB; mud and sand) and on cork oak leaves. Lower values of α (initial slope of the rETR, relative photosynthetic electron transport rate) vs E (incident photosynthetic active radiation) curve), ETR(max) (maximum relative ETR), E(k) (light saturation parameter) and F(v)/F(m) (maximum quantum efficiency of photosystem II of dark-adapted samples) were obtained using the Imaging-PAM. The level of discrepancy between conventional and Imaging-PAM systems was dependent on the type of sample, being more pronounced for MPB muddy sediments. This may be explained by differences in the depth integration of the fluorescence signal related to the thickness of the photosynthetic layer and in the light attenuation coefficients of downwelling irradiance. An additional relevant parameter is the taxonomic composition of the MPB, as cyanobacteria present in sandy sediments rendered different results with red and blue excitation light fluorometers. These findings emphasize the caution needed when interpreting chlorophyll fluorescence data of MPB communities.

Statistical methods for assessing agreement between double readings of clinical measurements.

UNLABELLED: Statistical analysis of data is crucial in cephalometric investigations. There are certainly excellent examples of good statistical practice in the field, but some articles published worldwide have carried out inappropriate analyses. OBJECTIVE: The purpose of this study was to show that when the double records of each patient are traced on the same occasion, a control chart for differences between readings needs to be drawn, and limits of agreement and coefficients of repeatability must be calculated. MATERIAL AND METHODS: Data from a well-known paper in Orthodontics were used for showing common statistical practices in cephalometric investigations and for proposing a new technique of analysis. RESULTS: A scatter plot of the two radiograph readings and the two model readings with the respective regression lines are shown. Also, a control chart for the mean of the differences between radiograph readings was obtained and a coefficient of repeatability was calculated. CONCLUSIONS: A standard error assuming that mean differences are zero, which is referred to in Orthodontics and Facial Orthopedics as the Dahlberg error, can be calculated only for estimating precision if accuracy is already proven. When double readings are collected, limits of agreement and coefficients of repeatability must be calculated. A graph with differences of readings should be presented and outliers discussed.

Statistical methods for assessing agreement between double readings of clinical measurements

Statistical analysis of data is crucial in cephalometric investigations. There are certainly excellent examples of good statistical practice in the field, but some articles published worldwide have carried out inappropriate analyses. OBJECTIVE: The purpose of this study was to show that when the double records of each patient are traced on the same occasion, a control chart for differences between readings needs to be drawn, and limits of agreement and coefficients of repeatability must be calculated. MATERIAL AND METHODS: Data from a well-known paper in Orthodontics were used for showing common statistical practices in cephalometric investigations and for proposing a new technique of analysis. RESULTS: A scatter plot of the two radiograph readings and the two model readings with the respective regression lines are shown. Also, a control chart for the mean of the differences between radiograph readings was obtained and a coefficient of repeatability was calculated. CONCLUSIONS: A standard error assuming that mean differences are zero, which is referred to in Orthodontics and Facial Orthopedics as the Dahlberg error, can be calculated only for estimating precision if accuracy is already proven. When double readings are collected, limits of agreement and coefficients of repeatability must be calculated. A graph with differences of readings should be presented and outliers discussed.

Perfil da publicação científica brasileira sobre a temática da classe hospitalar / Profile of Brazilian scientific publications on the subject of hospital shooling

O objetivo do trabalho foi descrever o perfi l da publicação científi ca brasileira sobre a temática da escolarização em hospitais, iniciativa justifi cada a partir do reconhecimento da importância da produção científi ca na legitimação e consolidação de uma nova área do saber. Foram analisados 47 artigos publicadosem periódicos científi cos entre os anos de 1997 e 2008. Tratou-se, basicamente, de um estudo de avaliação do Estado do Conhecimento (ou Estado da Arte) de uma área de interesse crescente dentro da Educação Especial: a escolarização de crianças hospitalizadas e/ou doentes crônicas, designada pelo MEC segundo o termo Classe Hospitalar. Do ponto de vista do corpus empírico, tratou-se de uma pesquisa documental, alicerçada metodologicamente na Análise de Conteúdo. Os artigos da amostra foram quantifi cados e qualifi cados segundo o tipo de investimento empírico predominante, quais fossem: ensaio, relato de experiência, relatos de pesquisa original (pesquisa com desenho de investigação) ou revisão de literatura. Buscou-se, também, identifi car se o periódico ao qual o artigo pertencia encontrava-se indexado em bases de dados: SciELO, Edubase, Bireme e catálogo do INEP. Descreveu-se, ainda, a distribuição dos artigos por área de conhecimento e por instituições de onde provinham. Os principais resultados obtidos revelaram que dos 47 artigos analisados 22 foram classifi cados como sendo oriundos de pesquisa original, apenas dois periódicos encontravam-se indexados em todas as bases de dados consideradas em relevância e as publicações foram originadas, em sua grande parte, da atividade de pesquisadores estabelecidos em instituições federais de ensino superior.

The aim of this paper was to describe the profi le of Brazilian scientifi c publications on the topic of education in hospitals, an initiative justifi ed since the recognition of the importance of scientifi c output in legitimizing and consolidating this new area of knowledge. We analyzed 47 articles published in scientifi c journals between the years 1997 to 2008. Basically, the study assessed the state of knowledge (or state of the art) of an area of growing interest and importance within the fi eld of Special Education: the education of hospitalizedchildren and/or chronic patients, designated by the Brazilian Ministry of Education under the term Hospital Schooling. From the standpoint of the empirical corpus, this was a documentary study, methodologically based on a technique called Content Analysis. The articles of the sample were classifi ed and quantifi ed according to the predominant type of empirical investment, i.e.: essay, case study, reports of original research (survey with design of research) and literature review. We also sought to identify the indexation databases to which the journals in question pertained, such as: SciELO, Edubase, Bireme and INEP catalog. We also described the distribution of thearticles by area of expertise and institutions they came from. The main results showed that 22 of the 47 articles analyzed were classifi ed as having been derived from original research; only two journals were indexed in all the relevant databases, and most the publications were produced by researchers working in federal institutions of higher education.

Percepção das puérperas sobre a assistência prestada pela equipe de saúde no pré-natal / Perceptions among pregnant women on pre-natal care provided by the health team / La percepción de las puérperas sobre la asistencia prestada por el equipo de salud en el prenatal

Trata-se de uma pesquisa qualitativa e descritiva, objetivando identificar de que modo as puérperas usuárias de um serviço público de saúde de Porto Alegre percebem a assistência prestada pela equipe de saúde no pré-natal e o que pensam sobre o acesso, o acolhimento e o atendimento recebido durante esse período. Realizamos entrevista, em setembro de 2009, com 11 puérperas, em uma maternidade de Porto Alegre-RS. Os dados coletados foram analisados e discutidos à luz das recomendações do Ministério da Saúde para o atendimento no pré-natal, e estruturados em cinco categorias: adesão ao pré-natal; acesso, acolhimento e humanização; acompanhamento do profissional de saúde no pré-natal; a visibilidade do enfermeiro no pré-natal; e finalizando o pré-natal na maternidade. Concluímos que, apesar do Programa de Humanização no Pré-Natal e Nascimento e do esforço da instituição pesquisada em adequar as políticas de saúde no seu cotidiano, ainda existem lacunas em relação à assistência humanizada e holística à gestante e puérpera.

This is a qualitative and descriptive study whose aim is to identify in what way pregnant women users of the Brazilian public health service perceived of the care provided by the prenatal health care team, examining the conditions, care, and assistance received. We conducted interviews in September of 2009 with 11 mothers in a maternity hospital in Porto Alegre, RS, Brazil. The data was analyzed and discussed in light of the Brazilian Ministry of Health's recommendations for pre-natal care then structured into five categories: adherence to prenatal care; access, reception, and humanization; monitoring the health professional in prenatal; the visibility of nurses in prenatal care; and finalizing prenatal maternity. We conclude that despite the Humanization Program in Prenatal and Delivery and the effort of the research institution to adequate health policies into their daily lives, there are still gaps with respect to humane and holistic care for pregnant and puerperal women.

La presente es una investigación cualitativa y descriptiva, con el objetivo de identificar cómo las puérperas que acuden a un servicio público de salud perciben la asistencia prestada por parte del equipo de salud en el prenatal. Para el estudio se analizaron las condiciones, el cuidado y la ayuda recibida. Se hicieron entrevistas con 11 puérperas, en septiembre de 2009, en una maternidad de Porto Alegre-RS. Los datos se analizaron y discutieron según las recomendaciones del Ministerio de Salud para la atención prenatal, y se organizaron en cinco categorías: la adhesión a la atención prenatal; acceso, atención y humanización; la supervisión del profesional de salud en el período del prenatal; la visibilidad de las enfermeras en la atención prenatal; y la finalización del prenatal en la maternidad. Se concluye que a pesar del Programa de Humanización del Prenatal y Nacimiento y del esfuerzo de la institución investigada por adecuar las políticas de salud en su vida diaria, aún existen brechas en relación a una atención humanizada y holística a las mujeres embarazadas y puérperas.

Impacto da condição autoavaliada de saúde bucal na qualidade de vida / Self evaluated oral status impact on quality of life

Objetivo: Associar a percepção das pessoas sobre o impacto das condições de saúde e doença bucal na qualidade de vida, com as seguintes variáveis: faixa de idade, condições socioeconômicas, escolaridade, situação da dentição, utilização de serviços odontológicos e hábitos de higiene bucal. Métodos: Foi utilizado um indicador subjetivo (OHIP-14) para avaliar a percepção das pessoas sobre o impacto da condição autoavaliada de saúde bucal na qualidade de vida delas próprias. Foram levantados dados demográficos, situação da dentição, utilização de serviços odontológicos e hábitos de higiene bucal. A amostra foi constituída por funcionários das escolas estaduais da cidade de Montes Claros, Minas Gerais. A análise estatística foi feita por meio de testes paramétricos, usando o programa SPSS. Resultados: Idosos percebem e registram maior limitação funcional e mais dor do que jovens. Edentados percebem e registram maior limitação funcional e incapacidade física do que dentados. Pessoas que precisam de próteses bucais sentem o impacto dessa situação na qualidade de vida. Melhor saúde bucal está associada a melhores condições econômicas, maior escolaridade, à procura por serviços odontológicos pagos para prevenção ou rotina e uso regular de instrumentos de higiene dental. Conclusão: As condições de saúde e doença bucal percebidas pelas pessoas estão associadas às variáveis pesquisadas. Como as pessoas têm percepção do impacto da saúde bucal sobre a qualidade de vida, mais condições para a procura de serviços odontológicos para prevenção ou rotina e uso regular de instrumentos de higiene dental melhorariam a saúde bucal da população.

Objective: To associate people's perception of the impact of oral health and disease status on the quality of life, with the following variables: Age bracket, socioeconomic conditions, educational level, dentition status, use of dental services, and oral hygiene habits. Methods: A subjective indicator (OHIP-14) was used to evaluate people's perception of the impact of the self-evaluated oral health status on the quality of their own lives. A survey was made of demographic data, dentition status, use of dental services and oral hygiene habits. The sample was constituted by employees of state schools in the city of Montes Claros, Minas Gerais, Brazil. Statistical analysis was performed by parametric tests using the SPSS program. Results: The elderly perceived and recorded greater functional limitation and more pain than young persons. Edentulous perceived and recorded greater functional limitation and physical incapacity than dentate persons. Persons that required dental prostheses felt the impact of this situation on the quality of life. Better oral health is associated with better economic conditions, higher educational level, seeking paid dental services for prevention or routine care and regular use of dental hygiene instruments. Conclusion: The oral health and disease status perceived by people is associated with the researched variables. As people perceive the impact of oral health on the quality of life, more conditions to seek dental services for prevention or routine care and the regular use of dental hygiene instruments would improve the population's oral health.

Como elaborar questionários

Este livro foi escrito com a intenção de dar contribuição para todos aqueles que têm de desenvolver um questionário. Começa dando um panorama geral das pesquisas, explica as etapas da construção de um questionário, mostra como redigir as questões e como propor alternativas de resposta. A obra explica, ainda, as escalas de mensuração usadas nas ciências sociais, mostra como testar o questionário e como escolher os respondentes. A abordagem dos temas está acompanhada de exemplos em diversas áreas.

Committees for Ethics in Research involving human subjects.

In Brazil since October 1996 there have been guidelines for research involving human subjects. Now human subjects know when their treatment is part of research. Deceit is no longer tolerated. But is not enough to say we offer an explanation to the potential subject and we offer a choice before he or she is confronted with an informed consent form. As in all professional activity, scientific investigation needs social controls. In Brazil, the ultimate responsibility of an investigation lies on the investigator, but in every institution where research is carried out there is a Committee for Ethics in Research. All Committees are subordinated to the National Commission of Ethics in Research, which is submitted to the Brazilian Institute of Health. During 2005 around 17,000 protocols involving 700,000 human subjects were revised by 475 Committees distributed all over the country. Approximately 7,000 people are now working in these Committees.

Rapid light-response curves of chlorophyll fluorescence in microalgae: relationship to steady-state light curves and non-photochemical quenching in benthic diatom-dominated assemblages.

Rapid light-response curves (RLC) of variable chlorophyll fluorescence were measured on estuarine benthic microalgae with the purpose of characterising its response to changes in ambient light, and of investigating the relationship to steady-state light-response curves (LC). The response of RLCs to changes in ambient light (E, defined as the irradiance level to which a sample is acclimated to prior to the start of the RLC) was characterised by constructing light-response curves for the RLC parameters alpha (RLC), the initial slope, ETR(m,RLC), the maximum relative electron transport rate, and E (k,RLC), the light-saturation parameter. Measurements were carried out on diatom-dominated suspensions of benthic microalgae and RLC and LC parameters were compared for a wide range of ambient light conditions, time of day, season and sample taxonomic composition. The photoresponse of RLC parameters was typically bi-phasic, consisting of an initial increase of all parameters under low ambient light (E < 21-181 micromol m(-2) s(-1)), and of a phase during which alpha (RLC) decreased significantly with E, and the increase of ETR(m,RLC) and E (k,RLC) was attenuated. The relationship between RLC and LC parameters was dependent on ambient irradiance, with significant correlations being found between alpha (RLC) and alpha, and between ETR(m,RLC) and ETR(m), for samples acclimated to low and to high ambient irradiances, respectively. The decline of alpha (RLC) under high light (Deltaalpha (RLC)) was strongly correlated (P < 0.001 in all cases) with the level of non-photochemical quenching (NPQ) measured before each RLC. These results indicate the possibility of using RLCs to characterise the steady-state photoacclimation status of a sample, by estimating the LC parameter E (k), and to trace short-term changes in NPQ levels without dark incubation.

Ética e metodologia na pesquisa médica / Ethics and methodology in medical research

Os princípios éticos que devem ser respeitados na pesquisa médica, bem como o histórico do desenvolvimento de um pensamento sobre a bioética no Brasil e no mundo são apresentados. São enfatizadas a importância da Resolucão 196/96 do Conselho Nacional de Saúde e a preocupacão da Comissão Nacional de Ética em Pesquisa (CONEP) como orientadores para a conduta na pesquisa com seres humanos. Fundamentados naqueles princípios e na experiência mundial acumulada até agora são abordadas questões no sentido da máxima protecão ao participante de uma pesquisa em especial na área de saúde.

Impactos da saúde bucal sobre a qualidade de vida entre homens e mulheres / The impact of dental health in the life quality between men and women

Os indicadores subjetivos ou sócio dentais tem sido utilizados em diversos estudos, e um tipo deste indicador é o questionário OHIP (Oral Health Impact Profile) que mede a percepção do indivíduo das desordens bucais, associados a qualidade de vida. A versão original deste questionário apresenta 49 itens e a versão reduda 14 itens. O presente trabalho avaliou a relação entre homens e mulheres do impacto da saúde bucal na qualidade de vida. A pesquisa teve uma amostra de 298 questionários válidos. Dois roteiros de entrevistas padronizadas, foram utilizadas permitindo a obtenção de informações sobre usuários do serviço público odontológico da Beneficência da Prefeitura de Belo Horizonte (BEPREM), no Estado de Minas Gerais: a) Roteiro de Seleção de Participantes e o Oral Health Impact Profile - short form (OHIP-14). Ao aplicar-se o teste t-Student observou-se que não existe diferença estatisticamente significativa entre homens e mulheres, nas dimenções e no escore total do OHIP-14