Impact of Fabrication Parameters on the Internal Structure of Poly(3-hexylthiophene) Nanoparticles

Morphological control of organic functional materials is central to understanding and improving upon current technologies. The ability to create hierarchical assemblies with purposeful design from nano to meso scale has remained largely unattainable. This body of work aims to provide a foundation for creating nanoscale domains of poly (3-hexylthiophene) (P3HT) that can be used as building blocks to larger scale assemblies. We present a method for the fabrication of P3HT nanoparticles on the ability to vary the particle size and more importantly, the internal structure. We have identified the oil phase and surfactant as parameters able to influence the nature of P3HT aggregate within nanoparticles fabricated through the miniemulsion process

Job Satisfaction, Leadership Styles, and Teaching Practices among CNMI Public Elementary School Teachers

This study investigated whether teacher leadership styles and teaching practices influenced teacher job satisfaction among public elementary school teachers in the Commonwealth of the Northern Mariana Islands. The study answered the following questions: (1) what is the level of job satisfaction among public elementary school teachers in the CNMI; (2) to what extent do CNMI teachers fall into the personal leadership style categories of transactional or transformational; (3) to what extent do CNMI public school teachers prefer either didactic or constructivist teaching practices; (4) to what extent do demographic factors, preferred leadership styles, and preferred teaching practices affect the degree of job satisfaction expressed by the CNMI public elementary school teachers; and (5)to what extent does the interaction between leadership style and teaching practice affect the degree of job satisfaction expressed by the CNMI public elementary school teachers. This study used survey research and multiple regression to answer the questions. Teachers were moderately satisfied with their jobs. They preferred transformational leadership styles to transactional ones and didactic teaching practices to constructivist ones. The dependent variable job satisfaction, when regressed against the eight independent variables age, gender, years teaching, highest degree held, English as a mother tongue, leadership styles, teaching practices, and an interaction variable between leadership styles and teaching practices called agreement, was found to be significantly influenced by only gender and agreement. For gender, females were more satisfied than men, and for agreement, teachers whose leadership styles and teaching practices were in dissonance were more satisfied than those whose styles and practices were in harmony

Facebook : espaço para expressão e comunicação

Os websites de redes sociais representam o que há de mais contemporâneo na comunicação e interação entre os internautas. O Facebook é a segunda rede social mais usada no Brasil. Um grupo de amigos desta rede foi entrevistado a fim de se constatar o uso que estes fazem na rede. Para a realização da entrevista foram usados o Google Docs, Pbwiki e uma ferramenta do próprio Facebook, chamada eventos. O problema “A rede social Facebook serve como um recurso significativo na vida destas pessoas?” foi respondida com base em dados informados na pesquisa. Muitos gostam da ideia de compartilhar informações e se identificam como produtores de conteúdo. A maioria dos entrevistados evidencia que entendeu a proposta da rede social e faz bom uso dela no cotidiano. As respostas recebidas foram comparadas e estudadas com base em autores e suas publicações.The social networking web sites represent what is most contemporary communication and interaction among bloggers. Facebook is the second most used social network in Brazil. A group of friends this network was interviewed to see if they are using the network. For the interview were used Google Docs, a tool and PBwiki's own Facebook network, called events. The problem, "Social network Facebook serves as a significant resource in the lives of these people?" Was answered based on data reported in the survey. Many like the idea of sharing information and identifying themselves as content producers. Most respondents considered the proposal shows that social networking and makes good use of it in everyday life. The responses were compared and evaluated based on authors and their publications

Differential virus restriction patterns of rhesus macaque and human APOBEC3A: Implications for lentivirus evolution

AbstractThe human apolipoprotein B mRNA editing enzyme catalytic peptide-like 3 (APOBEC3; A3) family of proteins (A3A-H) are known to restrict various retroviruses and retroelements, but the full complement of rhesus macaque A3 proteins remains unclear. We report the isolation and characterization of the hA3A homologue from rhesus macaques (rhA3A) and show that the rhesus macaque and human A3 genes are orthologous. RhA3A is expressed at high levels in activated CD4+ T cells, is widely expressed in macaque tissues, and is degraded in the presence of the human immunodeficiency virus (HIV-1) and simian–human immunodeficiency virus (SHIV) genomes. Our results indicate that rhA3A is a potent inhibitor of SHIVΔvif and to a lesser extent HIV-1Δvif. Unlike hA3A, rhA3A did not inhibit adeno-associated virus 2 (AAV-2) replication and L1 retrotransposition. These data suggest an evolutionary switch in primate A3A virus specificity and provide the first evidence that a primate A3A can inhibit lentivirus replication

Isorhapontigenin, a resveratrol analogue selectively inhibits ADP-stimulated platelet activation

Isorhapontigenin is a polyphenolic compound found in Chinese herbs and grapes. It is a methoxylated analogue of a stilbenoid, resveratrol, which is well-known for its various beneficial effects including anti-platelet activity. Isorhapontigenin possesses greater oral bioavailability than resveratrol and has also been identified to possess anti-cancer and anti-inflammatory properties. However, its effects on platelet function have not been reported previously. In this study, we report the effects of isorhapontigenin on the modulation of platelet function. Isorhapontigenin was found to selectively inhibit ADP-induced platelet aggregation with an IC50 of 1.85µM although it displayed marginal inhibition on platelet aggregation induced by other platelet agonists at 100µM. However, resveratrol exhibited weaker inhibition on ADP-induced platelet aggregation (IC50>100µM) but inhibited collagen induced platelet aggregation at 50µM and 100µM. Isorhapontigenin also inhibited integrin αIIbβ3 mediated inside-out and outside-in signalling and dense granule secretion in ADP-induced platelet activation but interestingly, no effect was observed on α-granule secretion. Isorhapontigenin did not exert any cytotoxicity on platelets at the concentrations of up to 100µM. Furthermore, it did not affect haemostasis in mice at the IC50 concentration (1.85µM). In addition, the mechanistic studies demonstrated that isorhapontigenin increased cAMP levels and VASP phosphorylation at Ser157 and decreased Akt phosphorylation. This suggests that isorhapontigenin may interfere with cAMP and PI3K signalling pathways that are associated with the P2Y12 receptor. Molecular docking studies emphasised that isorhapontigenin has greater binding affinity to P2Y12 receptor than resveratrol. Our results demonstrate that isorhapontigenin has selective inhibitory effects on ADP-stimulated platelet activation possibly via P2Y12 receptor

Facebook : espaço para expressão e comunicação

Os websites de redes sociais representam o que há de mais contemporâneo na comunicação e interação entre os internautas. O Facebook é a segunda rede social mais usada no Brasil. Um grupo de amigos desta rede foi entrevistado a fim de se constatar o uso que estes fazem na rede. Para a realização da entrevista foram usados o Google Docs, Pbwiki e uma ferramenta do próprio Facebook, chamada eventos. O problema “A rede social Facebook serve como um recurso significativo na vida destas pessoas?” foi respondida com base em dados informados na pesquisa. Muitos gostam da ideia de compartilhar informações e se identificam como produtores de conteúdo. A maioria dos entrevistados evidencia que entendeu a proposta da rede social e faz bom uso dela no cotidiano. As respostas recebidas foram comparadas e estudadas com base em autores e suas publicações.The social networking web sites represent what is most contemporary communication and interaction among bloggers. Facebook is the second most used social network in Brazil. A group of friends this network was interviewed to see if they are using the network. For the interview were used Google Docs, a tool and PBwiki's own Facebook network, called events. The problem, "Social network Facebook serves as a significant resource in the lives of these people?" Was answered based on data reported in the survey. Many like the idea of sharing information and identifying themselves as content producers. Most respondents considered the proposal shows that social networking and makes good use of it in everyday life. The responses were compared and evaluated based on authors and their publications

Fabrication Conditions for Efficient Organic Photovoltaic Cells from Aqueous Dispersions of Nanoparticles

For environmentally friendly and cost-effective manufacturing of organic photovoltaic (OPV) cells, it is highly desirable to replace haloarenes with water as the active layer fabrication solvent. Replacing an organic solvent with water requires retooling the device fabrication steps. The optimization studies were conducted using poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61 butyric acid methyl ester (PCBM) as active layer materials. These materials were dispersed in water as blend and separate nanoparticles using the miniemulsion method. Topologies of the active layers were investigated using atomic force microscopy and electron microscopy techniques. We have identified two essential steps to fabricate efficient OPVs from aqueous dispersions: (1) treatment of the hole-transport layer with UV-O3 to make the surface hydrophilic and (2) the use of an electron-transporting buffer layer for efficient charge extraction. We have also identified relative humidity and substrate temperature as key fabrication parameters for obtaining uniform active layer films. The OPV devices were fabricated using PEDOT:PSS as the hole-transport layer and PCBM as electron-transport layer with Ca/Al as the counter electrode. Efficiencies of 2.15% with a fill factor over 66% were obtained; the efficiency and the fill-factor is the highest among all aqueous processing of P3HT–PCBM nanoparticle solar cells