Preparation of capacitor’s electrode from sunflower seed shell

Series of nanoporous carbons are prepared from sunflower seed shell (SSS) by two different strategies and used as electrode material for electrochemical double-layer capacitor (EDLC). The surface area and pore-structure of the nanoporous carbons are characterized intensively using N₂ adsorption technique. The results show that the pore-structure of the carbons is closely related to activation temperature and dosage of KOH. Electrochemical measurements show that the carbons made by impregnation-activation process have better capacitive behavior and higher capacitance retention ratio at high drain current than the carbons made by carbonization-activation process, which is due to that there are abundant macroscopic pores and less interior micropore surface in the texture of the former. More importantly, the capacitive performances of these carbons are much better than ordered mesoporous carbons and commercial wood-based active carbon, thus highlighting the success of preparing high performance electrode material for EDLC from SSS.     

Membrane microheterogeneity: Förster resonance energy transfer characterization of lateral membrane domains

Lateral membrane heterogeneity, in the form of lipid rafts and microdomains, is currently implicated in cell processes including signal transduction, endocytosis, and cholesterol trafficking. Various biophysical techniques have been used to detect and characterize lateral membrane domains. Among these, Förster resonance energy transfer (FRET) has the crucial advantage of being sensitive to domain sizes smaller than 50-100 nm, below the resolution of optical microscopy but, apparently, similar to those of rafts in cell membranes. In the last decade, several formalisms for the analysis of FRET in heterogeneous membrane systems have been derived and applied to the study of microdomains. They are critically described and illustrated here.     

Potential new areas for conservation of key botanical families in the subtropical Atlantic Forest

Myrtaceae, Lauraceae and Fabaceae are regarded as essential floristic elements of Atlantic forests due to their outstanding species richness, endemism levels, and ecological functions. Nonetheless, Atlantic forests are being subjected to multiple human disturbances that compromise the conservation of their flora. This study, therefore, intended to address whether there exist potential areas for conservation with great richness of tree/shrub species of the aforementioned families in different forest types within the subtropical Atlantic Forest. For this, data collected systematically across?~?23% of the subtropical Brazilian Atlantic Forest were employed. The univariate Local Moran I statistic was used to search for clusters of sample plots with great richness of species of the studied families. Six clusters were found throughout the evergreen rainforest (ERF) and Araucaria forest (AF), and most of them contained more than half of all species of these families observed on the sample plots, besides many others belonging to different families. A cluster of Myrtaceae and a cluster of Lauraceae in the ERF were the only ones that overlapped protected areas. The clusters of Lauraceae in the AF, located in ecotone zones with the ERF, had?~?50% of native forest cover, whereas the clusters of Myrtaceae and Fabaceae had?~?10% of forest cover. Inasmuch as forests in the study area have been heavily exploited, the clusters have relevant conservation value. Protected areas could be expanded or converted into more restrictive conservation categories to enhance the conservation of populations of key elements of the Atlantic Forest. Yet, non-protected areas deserve attention regarding the management of forest resources and conservation-by-use strategies.

     

The alkene monooxygenase from Xanthobacter Py2 is a binuclear non-haem iron protein closely related to toluene 4-monooxygenase

The genes encoding the six polypeptide components of the alkene monooxygenase from Xanthobacter Py2 have been sequenced. The predicted amino acid sequence of the first ORF shows homology with the iron binding subunits of binuclear non-haem iron containing monooxygenases including benzene monooxygenase, toluene 4-monooxygenase (>60% sequence similarity) and methane monooxygenase (>40% sequence similarity) and that the necessary sequence motifs associated with iron co-ordination are also present. Secondary structure prediction based on the amino acid sequence showed that the predominantly α-helical structure that surrounds the binuclear iron binding site was conserved allowing the sequence to be modelled on the co-ordinates of the methane monooxygenase α-subunit. Significant differences in the residues forming the hydrophobic cavity which forms the substrate binding site are discussed with reference to the differences in reaction specificity and stereospecificity of binuclear non-haem iron monooxygenases.     

The Isolation and Characterization of Glycosylated Phosphoproteins from Herring Fish Bones

Past studies of bone extracellular matrix phosphoproteins such as osteopontin and bone sialoprotein have yielded important biological information regarding their role in calcification and the regulation of cellular activity. Most of these studies have been limited to proteins extracted from mammalian and avian vertebrates and nonvertebrates. The present work describes the isolation and purification of two major highly glycosylated and phosphorylated extracellular matrix proteins of 70 and 22 kDa from herring fish bones. The 70-kDa phosphoprotein has some characteristics of osteopontin with respect to amino acid composition and susceptibility to thrombin cleavage. Unlike osteopontin, however, it was found to contain high levels of sialic acid similar to bone sialoprotein. The 22-kDa protein has very different properties such as very high content of phosphoserine (∼270 Ser(P) residues/1000 amino acid residues), Ala, and Asx residues. The N-terminal amino acid sequence analysis of both the 70-kDa (NPIMA(M)ETTS(M)DSKVNPLL) and the 22-kDa (NQDMAMEASSDPEAA) fish phosphoproteins indicate that these unique amino acid sequences are unlike any published in protein databases. An enzyme-linked immunosorbent assay revealed that the 70-kDa phosphoprotein was present principally in bone and in calcified scales, whereas the 22-kDa phosphoprotein was detected only in bone. Immunohistological analysis revealed diffusely positive immunostaining for both the 70- and 22-kDa phosphoproteins throughout the matrix of the bone. Overall, this work adds additional support to the concept that the mechanism of biological calcification has common evolutionary and fundamental bases throughout vertebrate species.     

Effects of 1-ethynylpyrene and related inhibitors of P450 isozymes upon benzo[a]pyrene metabolism by liver microsomes

The effects of three aryl acetylenes, 1-ethynylpyrene (EP), 2-ethynylnaphthalene (EN) and 3-ethynylperylene (EPE), upon the metabolism of benzo[a]pyrene (BaP) by microsomes isolated from rat liver were investigated. These aryl acetylenes all inhibited the total metabolism of BaP. Formation of BaP 7,8-dihydrodiol and BaP tetrol products by microsomal preparations from rats that had been pretreated with 3-methylcholanthrene (3MC) were preferentially inhibited. The effects of EP upon the metabolism of BaP 7,8-dihydrodiol by microsomes from rat liver were also studied. This aryl acetylene strongly inhibited the formation of BaP tetrols from BaP 7,8-dihydrodiol by liver microsomes both from untreated rats and from rats pretreated with 3MC, but enhanced the conversion of the BaP dihydrodiol into other metabolites.     

Resolving the Conflicts Between Biodiversity Conservation and Socioeconomic Development in China: Fuzzy Clustering Approach

Resolving the conflicts between biodiversity conservation and socioeconomic development is a global pursuit for the long-run prospects of the human species. Based on Wenchuan County, a typical county in southwestern China, a group of 20 indicators quantifying regional biodiversity and socioeconomic development was established to classify and evaluate the county area spatially. A fuzzy c-means clustering (FCM) algorithm was used as the classification method. Three indices including BD, DL and DR characterizing the value of biodiversity, the level and rate of socioeconomic development of the delineated regions were formulated. The results indicated that Wenchuan County was optimally classified into 4 types of regions (region I to IV). The area percentages of the regions vary widely from 4.3 to 65.7%. The sequences of the regions on biodiversity, socioeconomic development level, and socioeconomic development rate were, respectively, IV > II > III > I, I > III > II > IV and III >I >II >IV. The spatial strategy on coordinating biodiversity conservation and regional development is to develop mainly from the east(I, II, III) and to conserve mainly in the west(IV). Eco-industry, such as eco-tourism and eco-agriculture, need to be emphasized in the process of regional development. The quantitative methods used here may have a wide applicability.     

Digest: Developmental life history and adaptive radiation in salamanders*

What determines the rate at which species adapt to new climatic conditions? Weaver et al. found that the evolution of short larval periods promotes climatic niche evolution in salamanders in the genus Desmognathus.