Polyacetylenes Bearing Chiral-Substituted Fluorene and Terfluorene Pendant Groups: Synthesis and Properties

The synthesis of the first polyacetylenes bearing chiral fluorene-based pendant groups is described. Poly{9,9-bis[(S)-3,7-dimethyloctyl]fluoren-2-ylacetylene} (PFA1), poly{9,9-bis[(S)-2-methylbutyl]- fluoren-2-ylacetylene} (PFA2), and poly{9,9,9′,9′,9′′,9′′-hexakis[(S)-2-methylbutyl]-7,2′;7′,2′′-terfluoren- 2-ylacetylene} (PFA3) have been obtained by Rh(I)-catalyzed polymerization of the corresponding terminal acetylene monomers 2-ethynyl-9,9-bis[(S)-3,7-dimethyloctyl]fluorene (2a), 2-ethynyl-9,9-bis[(S)-2-methylbutyl]fluorene (2b), and 2-ethynyl-9,9,9′,9′,9′′,9′′-hexakis[(S)-2-methylbutyl]-7,2′;7′,2′′-terfluorene (10). The effect of the alkyl chain length at the C-9 position of fluorene on the structural and conformational aspects of the polymers PFA1 and PFA2 as well as on their chiroptical properties was studied by XRD, DSC, TGA, GPC, UV-vis, and CD. A more planar conformation of the polyenic backbone of PFA1 with respect to PFA2 can be inferred by a red shift of the ð-ð* transition in the UV-vis spectra. Their photoluminescence properties are those typical of fluorene systems. CD measurements evidenced Cotton effects of opposite signs in correspondence of the backbone absorption region, ascribable to an excess of a screw sense of the helical conformations assumed by the two polymers. PFA3 revealed an amorphous structure and exhibited peculiar thermal stability features (as indicated by TGA and DSC). Its emission spectra interest the violet-blue region and do not show any substantial red shift passing from solution to solid state, thus pointing out an aggregation prevention of terfluorene groups by means of the polyacetylene backbone

Detecção de Grapevine vírus A no Vale do Sirigi, Zona da Mata de Pernambuco.

Iniciando-se um levantamento e caracterização de vírus, foram coletados ramos de videira das cvs. Isabel, de cultivos tradicionais, Isabel Precoce, Niágara Rosada e Patrícia em São Vicente Férrer, dos quais foram extraídos RNAs total e analisado com um kit One Step RT-PCR com primers específicos para, Grapevine virus A (GVA), Grapevine virus B, Grapevine fanleaf virus e Grapevine leafroll- associated virus-3

Multitrait selection in seedless grape hybrids in semiarid regions of Brazil.

The absence of seeds has been one of the most valued traits in grapes (Vitis spp.) for fresh consumption. However, the simultaneous selection of superior genotypes for multiple traits is complex. The objective of this study was to select genotypes of superior seedless table grapes in semiarid regions of Brazil. Multiple traits were considered by using the factor analysis and genotype?ideotype best linear unbiased prediction (FAI-BLUP) selection index. A total of 110 grape progenies from 24 crosses were evaluated for traits of agronomic interest. Each hybrid was represented by a single vine plant, without experimental design or repetition. The mixed-model methodology was used to predict the breeding values. The FAI-BLUP index was used to select superior genotypes based on factor analysis and the genotype?ideotype distance. Four factors explained the 11 characteristics studied, with a variability of 81.84%. Desirable gains were observed for 10 of the 11 traits evaluated. The FAI-BLUP index allowed the selection of superior seedless table grape hybrids, which can be used in the genetic improvement of grapevines. In conclusion, we report the selection of seedless table grape hybrids for our study to advance in the table grape breeding program in Brazilian semiarid regions.On-line

Evaluation of grapevines for resistance to downy mildew (Plasmopara viticola) under greenhouse conditions.

Grapevine downy mildew, caused by the fungus Plasmopara viticola is a disease with a great economic impact on grapevine in the Brazil. The objective of this study was to evaluate resistance to downy mildew in seedless grapevine hybrids and one susceptible cultivar ?Thompson Seedles? using natural infection (cross-contamination) and artificial inoculation method under greenhouse conditions. The experiments were performed at Embrapa Semiarid, Petrolina, Pernambuco, Brazil. The first used natural infection from plants with diseased vines, and the second artificial infection in which plants were sprayed with a spore suspension with a concentration of 105 conidia mL-1. The evaluated variables were final incidence, final severity, area under the curve of disease incidence progression and area under the curve of disease severity progression. All evaluated genotypes showed symptoms of downy mildew. The CPATSA 28.14 genotype presented the lowest values of final severity, final incidence, area under the disease severity progress curve and area under the disease incidence progress curve in both experiments. Therefore, the CPATSA 28.14 genotype was identified as having greater resistance to grapevine downy mildew. Clustering by the unweighted pair grouping method using arithmetic averages (UPGMA) resulted in the separation of the genotypes into three and two similarity groups in Experiments I and II, respectively, indicating low diversity among the grapevine hybrids evaluated.On line

Comparação entre ELISA e RT-PCR na detecção de vírus em parreirais no Nordeste do Brasil.

Resumo apresentado de número 604-1

Allergy in adolescent population (14-18 years) living in campania region (southern Italy). a multicenter study

Adolescents (Ad) constitute a difficult to manage population among individuals suffering from asthma. The aim of our study was to assess the prevalence, clinical characteristics and age of onset of allergic sensitization and clinical symptoms in a sample of atopic Ad living in the Campania region (Southern Italy). Sixteen Allergy units or Centers belonging to the Italian Association of Hospital and Territorial Allergologists (AAIITO, Campania region) participated in this cross-sectional study. A case report form (CRF) was specifically designed for this study and commercial allergen extracts used for screening SPTs were provided by ALK-Abelló Group (Milan, Italy). A total of 443 patients were examined (females, f 220, 49.6 %; males, m 223, 50.3%). Dust mites represent the most common sensitizing agents in allergic Ad living in Campania region (Dermatoph. pteronyssinus 67.4% and Dermatoph. farinae 66.5%), followed by Parietaria (58.9%), grasses (45.8%), Artemisia vulgaris (16.7%), Olea Europaea (32.2%), dog dander (17.1%), cat dander (20.0%), Alternaria alternata (8.1%), Cupressus sempervirens (4.9%), Betula pendula (4.7%), other allergens (19.4%). An interesting comparison has been made between clinical data of our Ad with data of elderly patients (E). The role of allergic sensitization is significantly higher in Ad compared to E. Dermatophagoides pteronyssinus is the first sensitizing allergen in Ad and the last in E. Parietaria constitutes the first sensitizing pollen both in Ad and E, the percentage of sensitization is higher in Ad. Another important difference is the higher prevalence of As, as only symptom, in E compared to Ad (19.7% versus 7.6%). In conclusion, our findings confirm the high prevalence and clinical significance of airway allergic sensitization in the adolescents living in Campania region