Polyhedral Oligomeric Silsesquioxane-phosphate Glass Matrix Nanocomposites with Additional Chapter on Phosphate Glass-Poly(ethylene terephthalate) Matrix Composites

Preparation and characterization of tin fluorophosphate glass (Pglass) matrix nanocomposites incorporating polyhedral oligomeric silsesquioxane (POSS) were investigated on the structural, thermal, morphological, mechanical, and rheological properties. Various processes including synthesis, extrusion and sintering processes were applied to prepare the nanocomposite samples. Another application of POSS with hydrophobic functional groups on the well-structured nanoscale silicate cage with three silanol groups was investigated to present the feasibility to use POSS molecule as a coating material on the surface of the hydrophilic inorganic glass. In addition, Poly(ethylene terephthalate) polymer matrix composites incorporating Pglass was studied to present the benefits of the Pglass with ultra-low glass transition temperature. The synthesized nanocomposites were effectively mixed in the carbon crucible by gases produced during the process, resulting in homogeneous dispersion of POSS in the Pglass matrix, showing transparent optical property and improved rheological, mechanical, and thermal properties. While during the extrusion process mechanical force was used to homogeneously mix the TSP-POSS in the Pglass matrix, determining highly porosity due to the function of a foaming agent of POSS. The studies revealed tunable morphology with respect to the amount of POSS and extrusion conditions. 29Si Solid state NMR showed that after extrusion process silanol groups of TSP-POSS are all consumed by condensation reaction, consistent with the result of NMR analysis using the Pglass matrix nanocomposites prepared by sintering process. The novel approach using POSS molecule which is grafting hydrophobic function groups on the core, are utilized to lead increased hydrophobicity of the glass surface. To mimick a lotus leaf with a combination of roughness and low surface energy, the micro-sized Pglass particle and hydrophobic POSS were used. Contact angle of the obtained surface-modified hydrophobic Pglass showed significant improvement compared to pure Pglass bulk. In addition, Pglass/PET hybrids were successfully prepared using a mixing process. Various characterizations were performed to understand structure-property correlation in the hybrids with respect to amount of Pglass in the PET and experimental conditions. Unique properties of Pglass/PET hybrids are attributed to the plasticizer and nucleation effects of polydispersed Pglass particles as well as the increased interfacial interaction between two components in the hybrids

Finite Energy Electroweak Dyon

The recent MoEDAL experiment at LHC to detect the electroweak monopole makes the theoretical prediction of the monopole mass an urgent issue. We discuss different ways to estimate the mass of the electroweak monopole. We first present a scaling argument which indicates that the mass of the electroweak monopole to be around 4 TeV. To justify this we construct finite energy analytic dyon solutions which could be viewed as the regularized Cho-Maison dyon, modifying the coupling strengths of the electromagnetic interaction of $W$-boson in the standard model. Our result demonstrates that a genuine electroweak monopole whose mass scale is much smaller than the grand unification scale can exist, which can actually be detected at the present LHC.Comment: arXiv admin note: substantial text overlap with arXiv:hep-th/0210299, arXiv:hep-th/970703

Insights into eisosome assembly and organization

Eisosomes, large protein complexes that are predominantly composed of BAR-domain-containing proteins Pil1 and its homologs, are situated under the plasma membrane of ascomycetes. A successful targeting of Pil1 onto the future site of eisosome accompanies maturation of eisosome. During or after recruitment, Pil1 undergoes self-assembly into filaments that can serve as scaffolds to induce membrane furrows or invaginations. Although a consequence of the invagination is likely to redistribute particular proteins and lipids to a different location, the precise physiological role of membrane invagination and eisosome assembly awaits further investigation. The present review summarizes recent research findings within the field regarding the detailed structural and functional significance of Pil1 on eisosome organization

Smitin, a novel smooth muscle titin–like protein, interacts with myosin filaments in vivo and in vitro

Smooth muscle cells use an actin–myosin II-based contractile apparatus to produce force for a variety of physiological functions, including blood pressure regulation and gut peristalsis. The organization of the smooth muscle contractile apparatus resembles that of striated skeletal and cardiac muscle, but remains much more poorly understood. We have found that avian vascular and visceral smooth muscles contain a novel, megadalton protein, smitin, that is similar to striated muscle titin in molecular morphology, localization in a contractile apparatus, and ability to interact with myosin filaments. Smitin, like titin, is a long fibrous molecule with a globular domain on one end. Specific reactivities of an anti-smitin polyclonal antibody and an anti-titin monoclonal antibody suggest that smitin and titin are distinct proteins rather than differentially spliced isoforms encoded by the same gene. Smitin immunofluorescently colocalizes with myosin in chicken gizzard smooth muscle, and interacts with two configurations of smooth muscle myosin filaments in vitro. In physiological ionic strength conditions, smitin and smooth muscle myosin coassemble into irregular aggregates containing large sidepolar myosin filaments. In low ionic strength conditions, smitin and smooth muscle myosin form highly ordered structures containing linear and polygonal end-to-end and side-by-side arrays of small bipolar myosin filaments. We have used immunogold localization and sucrose density gradient cosedimentation analyses to confirm association of smitin with both the sidepolar and bipolar smooth muscle myosin filaments. These findings suggest that the titin-like protein smitin may play a central role in organizing myosin filaments in the contractile apparatus and perhaps in other structures in smooth muscle cells

Charged Black Cosmic String

Global U(1) strings with cylindrical symmetry are studied in anti-de Sitter spacetime. According as the magnitude of negative cosmological constant, they form regular global cosmic strings, extremal black cosmic strings and charged black cosmic strings, but no curvature singularity is involved. The relationship between the topological charge of a neutral global string and the black hole charge is clarified by duality transformation. Physical relevance as straight string is briefly discussed.Comment: ll pages, LaTe

Statistical Data Analysis Techniques Employed in Sport Marketing Quarterly: 1992 to 2004

This investigation was an assessment of data analysis statistical techniques used in Sport Marketing Quarterly (SMQ) from 1992 to 2004. In 159 quantitative data based articles reviewed, 360 uses of statistical data analysis techniques were identified. The techniques were classified by type of statistical data analysis method as descriptive statistics, parametric statistics, and nonparametric statistics. One half (50.00%) were used as descriptive statistics, 41.94% as parametric statistics, and less than one tenth (8.06%) as nonparametric statistics. Percentages and frequencies were the most frequent descriptive statistics used to answer the research purposes, questions, and/or hypotheses by the researchers of SMQ for this period. One-way ANOVA and regression analysis were the most frequent parametric statistics used and chi-square was the most frequent nonparametric statistic used. The intent of this investigation was to provide undergraduate and graduate students, their instructors, and other scholars with an overview of the most frequently used statistical data analysis techniques used in SMQ during its first 13 years. In addition, this study has provided some insight into the directions of the research conducted in sport marketing studies from a research methodology standpoint. For a new and developing academic area such as sport marketing, it is important for its consumers to know how such an area advances relative to its research methods

Inactivation of Tor proteins affects the dynamics of endocytic proteins in early stage of endocytosis

Tor2 is an activator of the Rom2/Rho1 pathway that regulates α-factor internalization. Since the recruitment of endocytic proteins such as actin-binding proteins and the amphiphysins precedes the internalization of α-factor, we hypothesized that loss of Tor function leads to an alteration in the dynamics of the endocytic proteins. We report here that endocytic proteins, Abp1 and Rvs167, are less recruited to endocytic sites not only in tor2 but also tor1 mutants. Furthermore, we found that the endocytic proteins Rvs167 and Sjl2 are completely mistargeted to the cytoplasm in tor1Δtor2ts double mutant cells. We also demonstrate here that the efficiency of endocytic internalization or scission in all tor mutants was drastically decreased. In agreement with the Sjl2 mislocalization, we found that in tor1Δtor2ts double mutant cells, as well as other tor mutant cells, the overall PIP2 level was dramatically increased. Finally, the cell wall chitin content in tor2ts and tor1Δtor2ts mutant cells was also significantly increased. Taken together, both functional Tor proteins, Tor1 and Tor2, are essentially required for proper endocytic protein dynamics at the early stage of endocytosis

Capping protein binding to actin in yeast: biochemical mechanism and physiological relevance

The mechanism by which capping protein (CP) binds barbed ends of actin filaments is not understood, and the physiological significance of CP binding to actin is not defined. The CP crystal structure suggests that the COOH-terminal regions of the CP α and β subunits bind to the barbed end. Using purified recombinant mutant yeast CP, we tested this model. CP lacking both COOH-terminal regions did not bind actin. The α COOH-terminal region was more important than that of β. The significance of CP's actin-binding activity in vivo was tested by determining how well CP actin-binding mutants rescued null mutant phenotypes. Rescue correlated well with capping activity, as did localization of CP to actin patches, indicating that capping is a physiological function for CP. Actin filaments of patches appear to be nucleated first, then capped with CP. The binding constants of yeast CP for actin suggest that actin capping in yeast is more dynamic than in vertebrates

Vps1 in the late endosome-to-vacuole traffic

Vacuolar protein sorting 1 (Vps1), the yeast homolog to human dynamin, is a GTP hydrolyzing protein, which plays an important role in protein sorting and targeting between the Golgi and late endosomal compartments. In this study, we assessed the functional significance of Vps1 in the membrane traffic towards the vacuole. We show here that vps1Δ cells accumulated FM4-64 to a greater extent than wild-type (WT) cells, suggesting slower endocytic degradation traffic toward the vacuole. In addition, we observed that two endosome-to-vacuole traffic markers, DsRed-FYVE and Ste2-GFP, were highly accumulated in Vps1-deficient cells, further supporting Vps1\u27s implication in efficient trafficking of endocytosed materials to the vacuole. Noteworthy, a simultaneous imaging analysis in conjunction with FM4-64 pulse-chase experiment further revealed that Vps1 plays a role in late endosome to the vacuole transport. Consistently, our subcellular localization analysis showed that Vps1 is present at the late endosome. The hyperaccumulation of endosomal intermediates in the vps1 mutant cells appears to be caused by the disruption of integrity of HOPS tethering complexes, manifested by mislocalization of Vps39 to the cytoplasm. Finally, we postulate that Vps1 functions together with the Endosomal Sorting Complex Required for Transport (ESCRT) complex at the late endosomal compartments, based on the observation that the double mutants, in which VPS1 along with singular ESCRT I, II and III genes have been disrupted, exhibited synthetic lethality. Together, we propose that Vps1 is required for correct and efficient trafficking from the late endosomal compartments to the vacuole