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Chemical and physical changes are necessary to improve the transport properties of polymeric membranes. Cellulose fiber pulp from Pinus taedawas processed in knives and balls mills in order to reduce the dimensions of the fibers for later application in polysulfone (PSf) membranes. By adding cellulosic fibers in PSf membranes, a composite membrane with improved morphological properties, permeate flux and good resistance to pressure was obtained. The fibers as well as the PSf and PSf/cellulose fibers membranes were morphologically characterized by scanning electron microscopy. Tests of pure water permeate flux were performed with pressure up to 20 bar. The addition of 0.2% (wt) of cellulose fibers in the formation of composite membranes resulted in the elimination of macrovoids, causing an increase in pure water flux (50% ±10) when pressure was risen.

Chemical and physical changes are necessary to improve the transport properties of polymeric membranes. Cellulose fiber pulp from Pinus taedawas processed in knives and balls mills in order to reduce the dimensions of the fibers for later application in polysulfone (PSf) membranes. By adding cellulosic fibers in PSf membranes, a composite membrane with improved morphological properties, permeate flux and good resistance to pressure was obtained. The fibers as well as the PSf and PSf/cellulose fibers membranes were morphologically characterized by scanning electron microscopy. Tests of pure water permeate flux were performed with pressure up to 20 bar. The addition of 0.2% (wt) of cellulose fibers in the formation of composite membranes resulted in the elimination of macrovoids, causing an increase in pure water flux (50% ±10) when pressure was risen.

Summary In this work, poly(styrenesulfonate) membranes were produced through the sulfonation of wasted polystyrene plastic cups. The produced membranes presented good workability and ion exchange capacity of 1.3±0.1 meq/g. The sulfonated membranes showed significantly increase in the water sorption, what is relevant in industry since most of the processes of separation deal with the presence of ions which means of transport is the water. The membrane of sulfonated polystyrene plastic cups (PSSwastecups) was compared with the sulfonated membrane of virgin resin (PSSstandard). The viscosimetric molar weight of PSSstandard was higher than PSSwastecups how indicated by difference between intrinsic viscosity. This fact influences the production of the membrane and consequently the transport property. The PSSwastecups absorbs a higher amount of water than the PSSstandard, what is due to the presence of less macromolecule chain coils, producing low-density regions where clusters may be formed. This diminishes the diffusion coefficient and increases the water sorption in the PSSwastecups membrane.

In the present work we blended cellulose acetate (taken from sugar cane bagasse) (CA) with polystyrene (taken from postconsumer plastic cups) (PS). The blends were produced in the following ratios (w/w) of the polymers: CA 50%/PS 50%, CA 90%/PS 10%, and CA 10%/PS 90%, using dichloromethane as solvent. The blends were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, and wide‐angle X‐ray diffraction. The results show that the presence of polystyrene hinders the organization of regions responsible for the crystallinity originally existing in pure cellulose acetate. We also made measurements of water flux through blends, using the Payne cup technique. The flux properties were compared with those obtained for commercial membranes by Osmonix: nanofiltration (SG) and reverse osmosis (CG). The results show that the blend CA 90%/PS 10% presents water vapor flux comparable with that of commercial membranes for nanofiltration (SG). © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 516–522, 2005

Nucleotide sequences, each spanning ∼7 kb of the contiguous γ1and γ2globin genomic loci, were determined for seven species representing all extant genera (Ateles, Lagothrix, Brachyteles,andAlouatta) of the New World monkey subfamily Atelinae. After aligning these seven ateline sequences with outgroup sequences from several other primate (non-ateline) genera, they were analyzed by maximum parsimony, maximum likelihood, and neighbor-joining algorithms. All three analyzes estimated the same phylogenetic relationships: {Alouatta[Ateles(Brachyteles, Lagothrix)]}.BrachytelesandLagothrixare sister-groups supported by 100% of bootstrap replications in the parsimony analyses.Atelesjoins this clade, followed by the basal genusAlouatta;these joinings were strongly supported, again with 100% bootstrap values. This cladistic pattern for the four ateline genera is congruent with that obtained in previous studies utilizing ϵ-globin, IRBP, and G6PD nuclear genomic sequences as well as mitochondrial COII sequences. Because the number of aligned nucleotide positions is much larger in the present dataset than in any of these other datasets, much stronger support was obtained for the cladistic classification that divides subfamily Atelinae into tribes Alouattini (Alouatta) and Atelini, while the latter divides into subtribes Atelina (Ateles) and Brachytelina (BrachytelesandLagothrix).

We sequenced the ∼5-kb long γ-globin gene locus from Tarsius bancanusand compared it to the published γ-globin gene sequence from the related species Tarsius syrichta.The T. syrichtagene's promoter lacks the distal CCAAT box and has a point mutation in the functionally important proximal CCAAT box (CCgAT). This previous finding had suggested that in tarsiers the γ-globin gene might be a nonexpressed pseudogene. The two tarsier species show the same point mutation at the third nucleotide of the proximal CCAAT element and absence of the distal CCAAT element. Nevertheless, our results indicate that in tarsiers the γ-globin gene is active, since all three coding regions show only synonymous substitutions and a much lower level of divergence than the noncoding regions. This is significantly different from what would be expected for a silent gene evading stabilizing selection. Thus, we hypothesize that the tarsier's γ-globin gene locus is expressed even with the mutation in the proximal CCAAT box.

Cowden syndrome (CS) is a rare dominantly inherited multisystem disorder, characterized by an extraordinary malignant potential. In 80% of cases, the human tumor suppressor gene phosphatase and tensin homolog (PTEN) is mutated. We present a case of a 17-year-old boy with genetically confirmed CS and Graves’ disease (GD). At the age of 15, he presented with intention tremor, palpitations, and marked anxiety. On examination, he had macrocephaly, coarse facies, slight prognathism, facial trichilemmomas, abdominal keratoses, leg hemangioma, and a diffusely enlarged thyroid gland. He started antithyroid drug (ATD) therapy with methimazole and, after a 2-year treatment period without achieving a remission status, a total thyroidectomy was performed. Diagnosis and management of CS should be multidisciplinary. Thyroid disease is frequent, but its management has yet to be fully defined. The authors present a case report of a pediatric patient with CS and GD and discuss treatment options.