Identification of intracellular calcium oxalate crystals in Chamelaucium uncinatum (Myrtaceae)

Intracellular inclusions in the pedicel and calyx-tube tissues of Chamelaucium uncinatum Schauer ( Myrtaceae) flowers are irregular in shape. They were shown, by polarised light and scanning electron microscopy, to be birefringent 8.9-29.5 mum druse (i.e. aggregate) crystals. Energy-dispersive X-ray spectroscopy showed that these crystals were predominantly composed of calcium. Histochemical and acid-solubility tests indicated that the crystals were calcium oxalate. Raman microprobe spectroscopy was used to confirm this chemical identity. The calcium oxalate crystals were located in xylem-vessel lumens and also in parenchyma cells adjacent to vascular tissues. Thus, the crystals may function to regulate soluble calcium concentrations in C. uncinatum tissues near sites where calcium is unloaded from the xylem.

Calcium treatment of harvested Geraldton waxflower does not enhance postharvest quality

Postharvest flower abscission from cut Geraldton waxflower (Chamelaucium uncinatum) is mostly caused by fungal invasion. Elevated plant tissue calcium concentrations through postharvest application reduces fungal disease severity in various crops. Such results may be explained by strengthening of plant cell walls by calcium. Strengthening provides a structural barrier to fungal hyphae, thereby restricting invasion of plant cells. Postharvest pulsing with calcium solution substantially increased calcium concentrations in waxflower tissues. Ca-45 tracer revealed calcium distribution throughout flowering sprigs, including infection sites such as stylar tissue. However, pulsing waxflower sprigs with calcium did not suppress either disease or flower abscission, nor did it enhance vase life.

Effect of organic amendments and solarisation on Fusarium wilt in susceptible banana plantlets, transplanted into naturally infested soil

Despite extensive research since pathogenicity was first established in 1919, no cultural or chemical control strategy has proven effective against Fusarium wilt of bananas. The efficacy of cultural control is attributed to the suppression of pathogen activity. Yet, amending naturally infested soil with aged chicken manure has been shown to enhance disease severity, without any change in the activity of the pathogen Fusarium oxysporum f. sp. cubense (Foc) in the soil. In this study, the effect of amending soil with composted sawdust, and of solarising soil, was compared with the effect of amending soil with chicken manure. Bioassays comparing the activity of Foc in the soil with the extent of invasion of banana pseudostem tissue by Foc were used to investigate why strategies targetting pathogen survival have not proven successful in controlling this disease. The enhancement of Foc invasion of the banana plantlets was reproduced with the addition of chicken manure to the naturally infested soil. However, changes in the activity of Foc in the soil were not associated with changes in the frequency of invasion of the plantlets. Invasion of banana pseudostems in the sawdust and solarisation treatments was not significantly different from invasion in the respective control treatments, despite a reduction in the activity of Foc in the sawdust-amended soil and an enhancement in the solarised soil. Moreover, the increase in Foc activity in the solarised soil recorded during the bioassays occurred despite the effectiveness of solarisation in reducing the survival of Foc in pre-colonised banana root tips buried in the soil. Changes in the frequency of invasion were associated with changes in the availability of mineral nitrogen, particularly ammonium N. These results suggest that the physiological response of banana cultivars to ammonium N may be associated with their susceptibility to Fusarium wilt. Accordingly, cultural strategies for controlling Panama disease will only be effective if they enhance the ability of the host to resist invasion.

Efficacy, timing and method of application of fungicides for management of sorghum ergot caused by Claviceps africana

Trials conducted in Queensland, Australia between 1997 and 2002 demonstrated that fungicides belonging to the triazole group were the most effective in minimising the severity of infection of sorghum by Claviceps africana, the causal agent of sorghum ergot. Triadimenol ( as Bayfidan 250EC) at 0.125 kg a. i./ha was the most effective fungicide. A combination of the systemic activated resistance compound acibenzolar-S-methyl ( as Bion 50WG) at 0.05 kg a. i./ha and mancozeb ( as Penncozeb 750DF) at 1.5 kg a. i./ha has the potential to provide protection against the pathogen, should triazole-resistant isolates be detected. Timing and method of fungicide application are important. Our results suggest that the triazole fungicides have no systemic activity in sorghum panicles, necessitating the need for multiple applications from first anthesis to the end of flowering, whereas acibenzolar-S-methyl is most effective when applied 4 days before flowering. The flat fan nozzles tested in the trials provided higher levels of protection against C. africana and greater droplet deposition on panicles than the tested hollow cone nozzles. Application of triadimenol by a fixed wing aircraft was as efficacious as application through a tractor-mounted boom spray.

An??lise da implementa????o do Programa Sistema Brasiliero de Tecnologia Sibratec Modalidade Extens??o Tecnol??gica

Este trabalho apresenta uma an??lise do processo de implementa????o do Programa Sistema Brasileiro de Tecnologia ??? SIBRATEC, programa do MCTI cujo objetivo geral ?? promover extens??o tecnol??gica para solucionar pequenos gargalos na gest??o tecnol??gica, adapta????o de produtos e processos e a melhoria da gest??o da produ????o das micro, pequenas e m??dias empresas, bem como desenvolver o fomento ?? expans??o do conhecimento cient??fico nas empresas.O objetivo deste trabalho foi avaliar o formato e a adequa????o dessa modalidade do programa a partir da contextualiza????o da implementa????o de pol??ticas que visam ao desenvolvimento da Ci??ncia Tecnologia e Inova????o ??? C T&I no Brasil, da caracteriza????o da pol??tica p??blica lan??adas e da coleta de dados, por meio de question??rio, sobre a percep????o dos coordenadores das redes apoiados pelo programa. A pesquisa permitiu concluir que o programa est?? alinhado ??s caracter??sticas da pol??tica atual de C T&I e que sua implementa????o ?? centrada na avalia????o ex-post. O programa foi considerado bastante adequado pelos coordenadores dos projetos de pesquisa apoiados. Em contrapartida, a continua????o do programa necessita de ajustes para que os objetivos previstos sejam alcan??ados em sua totalidade e a sistematiza????o da avalia????o do programa poder?? se constituir em uma ferramenta bastante ??til na gera????o dos subs??dios necess??rios para a tomada de decis??o sobre os novos rumos do Programa Sibratec

Candidíase laríngea isolada em paciente imunocompetente: relato de caso e revisão literária pertinente

Através de revisão de literatura, confirma-se que infecção laríngea por cândida é uma entidade rara e usualmente associada a infecção pulmonar ou candidíase disseminada¹. Candidíase em laringe de forma isolada (C.L.I.) é uma patologia ainda mais rara, e comumente relacionada a pacientes imunodeficientes². Sabe-se que à laringoscopia direta, a candidíase pode apresentar achados físicos pobres como simples hiperemia local ou mesmo leucoplasia, mimetizando patologias como DRGE até neoplasias, fazendo, pois, parte do diagnóstico diferencial. Encontramos e documentamos em nosso serviço um caso de infecção por cândida de forma isolada em laringe (C.L.I.) em paciente imunocompetente. Havia comprometimento laríngeo importante, inclusive com lesão deformante em epiglote, simulando processo neoplásico. O diagnóstico foi estabelecido por videolaringoscopia e 2 biópsias da lesão encontrada, sendo os materiais obtidos submetidos a 2 estudos histopatológicos. Tomamos o cuidado de afastar síndromes imunodeficitárias, inclusive de etiologia viral, através de pesquisa sorológica e investigação sobre abuso de corticoesteróides ou antibióticos sistêmicos. Fizemos o follow-up do paciente "per" e pós tratamento com antifúngico sistêmico, acompanhando evolução e melhora através da endoscopia e sinais clínicos.

Síntese e Avaliação Biológica de Novas Saponinas Imunoactivas

A saponina QS21 é uma saponina natural extraída da casca das árvores endémicas da América do Sul conhecida por desempenhar um papel importante como adjuvante de vacinas. O objectivo deste estudo foi determinar se os análogos sintéticos mais simples da QS-21 podem induzir respostas imunes com igual vantagem. Para isso, foram desenhados e sintetizados os ácidos 3-ß -O-(ß -D-xilopiranosil)-(1? 3)-[(ß -D-galactopiranosil)-(1? 2)]-6-ß -Dglucurónicos derivados de colestanol e amirina 1 e 2, respectivamente, ligando primeiro resíduos glucósidos ao terpeno e estendendo depois a cadeia de açúcar. A sua actividade adjuvante foi avaliada in vitro através da secreção de mediadores pró-inflamatórios de células IL-6 e IL-1, TNF-a e NO e os níveis de IgG no soro depois da estimulação in vivo das células apresentadoras de antigénio (APCs) . Os compostos 1 e 2 foram bastante mais citotóxicos para as células tumorais J744A.1 de murino do que a QS21 e mostraram menos actividade hemolítica indesejada nos glóbulos vermelhos do que a QS-21, mas não induziram respostas citotóxicas CD8 fortes após uma única injecção, o que aconteceu no processo de imunização com ovalbumina e QS-21. Apesar de os análogos 1 e 2 apresentarem boa actividade adjuvante in vitro, a ausência do grupo aldeído e da cadeia acilo é provavelmente o que afecta negativamente as propriedades das saponinas simplificadas para induzir células T citotóxicas activas em ratinhos.

Completion problems for real matrices, II

Thirty years ago, G.N. de Oliveira has proposed the following completion problems: Describe the possible characteristic polynomials of [C-ij], i,j is an element of {1, 2}, where C-1,C-1 and C-2,C-2 are square submatrices, when some of the blocks C-ij are fixed and the others vary. Several of these problems remain unsolved. This paper gives the solution, over the field of real numbers, of Oliveira's problem where the blocks C-1,C-1, C-2,C-2 are fixed and the others vary.

Sensor element for a metal-insulator-semiconductor camera system (MISCam)

We discuss the operation of a new type of optical sensor (MISCam) based on a metal-insulator-semiconductor (MIS) structure. The operation principle relies on light-induced changes of the band bending and barrier height at the interface between semiconductor and insulator. An image is obtained from the quenching of the ac signal in analogy to the principle of the laser-scanned photodiode (LSP). Lateral resolution depends on the semiconductor material chosen. We have characterised the MIS structures by C-V, I-V, and spectral response measurements testing different types of insulators like a-Si3N4, SiO2, and AlN. The presence of slow interface charges allows for image memory. Colour sensors can be realised by controlling sign and magnitude of the electric fields in the base and the interface region.

Extraction of hemoglobin with calixarenes and biocatalysis in organic media of the complex with pseudoactivity of peroxidase

The present work involves the use of p-tert-butylcalix[4,6,8]arene carboxylic acid derivatives ((t)Butyl[4,6,8]CH2COOH) for selective extraction of hemoglobin. All three calixarenes extracted hemoglobin into the organic phase, exhibiting extraction parameters higher than 0.90. Evaluation of the solvent accessible positively charged amino acid side chains of hemoglobin (PDB entry 1XZ2) revealed that there are 8 arginine, 44 lysine and 30 histidine residues on the protein surface which may be involved in the interactions with the calixarene molecules. The hemoglobin-(t)Butyl[6]CH2COOH complex had pseudoperoxidase activity which catalysed the oxidation of syringaldazine in the presence of hydrogen peroxide in organic medium containing chloroform. The effect of pH, protein and substrate concentrations on biocatalysis was investigated using the hemoglobin-(t)Butyl[6]CH2COOH complex. This complex exhibited the highest specific activity of 9.92 x 10(-2) U mg protein(-1) at an initial pH of 7.5 in organic medium. Apparent kinetic parameters (V'(max), K'(m), k'(cat) and k'(cat)/K'(m)) for the pseudoperoxidase activity were determined in organic media for different pH values from a Michaelis-Menten plot. Furthermore, the stability of the protein-calixarene complex was investigated for different initial pH values and half-life (t(1/2)) values were obtained in the range of 1.96 and 2.64 days. Hemoglobin-calixarene complex present in organic medium was recovered in fresh aqueous solutions at alkaline pH, with a recovery of pseudoperoxidase activity of over 100%. These results strongly suggest that the use of calixarene derivatives is an alternative technique for protein extraction and solubilisation in organic media for biocatalysis.

Diferenciação curricular na resposta às necessidades educativas especiais dos alunos

A i n c l u s ã o e m g e r a l e a e d u c a ç ã o i n c l u s i v a d o s a l u n o s c o m N E E e m p a r t i c u l a r s ã o p r i n c í p i o s o r i e n t a d o r e s d o s i s t e m a e d u c a t i v o p o r t u g u ê s . O s a g r u p a m e n t o s d e e s c o l a s , o s p r o f e s s o r e s , o s a l u n o s , o p e s s o a l a u x i l i a r d a s e s c o l a s e a s f a m í l i a s n ã o p õ e m e m c a u s a , a c t u a l m e n t e , o s f u n d a m e n t o s d e s t e p r i n c í p i o , c o m o m o s t r a m o s s e g u i n t e s e x c e r t o s d e e n t r e v i s t a s a p r o f e s s o r e s :

Adaptive mutations in bacteria: high rate and small effects

Evolution by natural selection is driven by the continuous generation of adaptive mutations. We measured the genomic mutation rate that generates beneficial mutations and their effects on fitness in Escherichia coli under conditions in which the effect of competition between lineages carrying different beneficial mutations is minimized. We found a rate on the order of 10–5 per genome per generation, which is 1000 times as high as previous estimates, and a mean selective advantage of 1%. Such a high rate of adaptive evolution has implications for the evolution of antibiotic resistance and pathogenicity.

Assessing the conservation status of the strict endemic Desertas wolf spider, Hogna ingens (Araneae, Lycosidae)

The Desertas Islands (Madeira, Portugal) are the sole home of one of the largest and rarest wolf spiderspecies, Hogna ingens (Blackwall 1857) (Araneae, Lycosidae). Despite its size, it inhabits a single valleyin the North of the Deserta Grande Island, Vale da Castanheira, currently invaded by the herb Phalarisaquatica. This invasive species competes with the native flora and was subject to several eradicationexperiments, namely through fire and chemicals. The objectives of this work were to: (1) estimate thecurrent distribution and abundance of H. ingens and respective trends; (2) evaluate the impact of theinvasive plant and eradication methods on the spider population; (3) suggest future measures for therecovery of the species; and (4) evaluate its conservation status according to the IUCN criteria. The current distribution of H. ingens covers 23 ha, a recent reduction from its original 83 ha, correspond-ing to the entire Vale da Castanheira. A total of 4447 and 4086 adults and 71,832 and 24,635 juvenileswere estimated to live in the valley during 2011 and 2012, respectively. We found a significant negativeimpact of P. aquatica cover on the presence and abundance of H. ingens and that chemical treatmentspecifically directed towards the invasive plant species may be the only way to effectively recover thespider's habitat. We suggest (1) regular monitoring; (2) extend chemical treatments; (3) ex-situ conserva-tion with future reintroduction of adults. Based on the current area of occupancy (AOO) of H. ingens and itsrecent decline in both AOO and number of individuals, it was recently classified as Critically Endangeredby IUCN and we suggest its urgent inclusion in the Habitats Directive species lists.

A indisciplina nas aulas de Educação Física : crenças de professores e de alunos : um estudo nas escolas dos Açores

[…]. Este livre que agora se publica resulta de mais uma tentativa de compreensão de factores subjacentes as situações de disciplina/indisciplina. Centra-se na óptica dos intervenientes, isto é, professores e alunos, e contém duas particularidades: a de procurar aduzir razões interpretativas da indisciplina no contexto da Educação Física e a de corresponder a um levantamento da situação num ambiente insular cuja descontinuidade territorial separa não só a Região Açores do continente português, mas também as diferentes ilhas que integram o Arquipélago. Pretende, então, neste contexto, fazer emergir informação fundamentada e circunstanciada sobre a temática, para que possa vir a ser utilizada no desenvolvimento da profissionalidade e do profissionalismo docentes e na educação para o bem-estar, para o desporto e para a cidadania dos jovens, em particular dos jovens açorianos. Resulta do esforço e do empreendimento de Isabel Condessa, especialista em Metodologia do Ensino da Educação Física, em colaboração com Isabel Estrela Rego e Suzana Nunes Caldeira, ambas especializadas em Psicologia da Educação. […].

Students' engagement in schools : differentiation and promotion

The objective of this work is to present elements of the project Student engagement in Schools (SES). The team consists of 10 researchers from six Universities. Student engagement in schools is a multidimensional construct that unites affective, behavioural, and cognitive dimensions of student adaptation in the school and has influence on students’outcomes. The team of researchers conceptualized two major studies, a differential study to analyze the relations between SES and contextual factors, personal factors, student’s outcomes, and a quasi-experimental study to analyze the effects on SES of a specific intervention programmes. In study 1, the sample size is around 600 students (150 6th graders, 150 7th graders, 150 9th graders, and 150 10th graders). We shall focus on years of school transition, with rural and urban populations, on different regions of the country, and on students with different family background. We shall conduct questionnaires with national and international scales. The study 2 will involve students in 7th and 9th grade, from four classes, two of the experimental group and two of the control group. Patterns of verbal communication between a teacher and students can influence the classroom environment and SES. This model of communication would result in more effective student management and more time on-task for learning.