Tailoring The Interface Using Thiophene Small Molecules In Tio 2/p3ht Hybrid Solar Cells

In this paper we focus on the effect of carboxylated thiophene small molecules as interface modifiers in TiO 2/P3HT hybrid solar cells. Our results show that small differences in the chemical structure of these molecules, for example, the presence of the -CH 2- group in the 2-thiopheneacetic acid (TAA), can greatly increase the TiO 2 surface wettability, improving the TiO 2/polymer contact. This effect is important to enhance exciton splitting and charge separation. This journal is © 2012 the Owner Societies.14341199011993Huang, Y.-C., Hsu, J.-H., Liao, Y.-C., Yen, W.-C., Li, S.-S., Lin, S.-T., Chen, C.-W., Su, W.-F., (2011) J. Mater. Chem., 21, p. 4450Bouclé, J., Ravirajan, P., Nelson, J., (2007) J. Mater. Chem., 17, p. 3141Bhongale, C.J., Thelakkat, M., (2010) Sol. Energy Mater. Sol. Cells, 94, p. 817Bolognesi, M., Sánchez-Díaz, A., Ajuria, J., Pacios, R., Palomares, E., (2011) Phys. Chem. Chem. Phys., 13, p. 6105Arici, E., Meissner, D., Schaffler, F., Sariciftci, N.S., (2003) Int. J. Photoenergy, 5, p. 199Arici, E., Sariciftci, N.S., Meissner, D., (2003) Adv. Funct. Mater., 13, p. 165De Freitas, J.N., Grova, I.R., Akcelrud, L.C., Arici, E., Sariciftcic, N.S., Nogueira, A.F., (2010) J. Mater. Chem., 20, p. 4845Yella, A., Lee, H.-W., Tsao, H.N., Yi, C., Chandiran, A.K., Nazeeruddin, M.K., Diau, E.W.-G., Grätzel, M., (2011) Science, 334, p. 629Yu, Q., Wang, Y., Yi, Z., Zu, N., Zhang, J., Zhang, M., Wang, P., (2010) ACS Nano, 4, p. 6032Lin, Y.-Y., Chu, T.-H., Li, S.-S., Chuang, C.-H., Chang, C.-H., Su, W.-F., Chang, C.-P., Chen, C.-W., (2009) J. Am. Chem. Soc., 131, p. 3644Sun, Z., Li, J., Liu, C., Yang, S., Yan, F., (2011) Adv. Mater., 23, p. 3648Coakley, K.M., Srinvasan, B.S., Ziebarth, J.M., Goh, C., Liu, Y.X., McGehee, M.D., (2005) Adv. Funct. Mater., 15, p. 1927Huang, Y.-C., Yen, W.-C., Liao, Y.-C., Yu, Y.-C., Hsu, C.-C., Ho, M.-L., Chou, P.-T., Su, W.-F., (2010) Appl. Phys. Lett., 96, p. 123501Zhang, W., Zhu, R., Li, F., Wang, Q., Liu, B., (2011) J. Phys. Chem. C, 115, p. 7038Johansson, E.M.J., Scholin, R., Siegbahn, H., Hagfeldt, A., Rensmo, H., (2011) Chem. Phys. Lett., 515, p. 146Ravirajan, P., Peiró, A.M., Nazeeruddin, M.K., Grätzel, M., Bradley, D.D.C., Durrant, J.R., Nelson, J., (2006) J. Phys. Chem. B, 110, p. 7635Weickert, J., Dunbar, R.B., Hesse, H.C., Wiedemann, W., Mende, L.S., (2011) Adv. Mater., 23, p. 1810Chang, J.A., Rhee, J.H., Im, S.H., Lee, Y.H., Kim, H.-J., Seok, S.I., Nazeeruddin, M.K., Gratzel, M., (2010) Nano Lett., 10, p. 2609Jiang, X., Karlsson, K.M., Gabrielsson, E., Johansson, E.M.J., Quintana, M., Karlsson, M., Sun, L., Hagfeldt, A., (2011) Adv. Funct. Mater., 21, p. 2944Snaith, H.J., Moule, A.J., Klein, C., Meerholz, K., Friend, R.H., Grätzel, M., (2007) Nano Lett., 7, p. 3372Weickert, J., Auras, F., Bein, T., Mende, L.S., (2011) J. Phys. Chem. C, 115, p. 15081Liu, Y., Scully, S.R., McGehee, M.D., Liu, J., Luscombe, C.K., Frechet, J.M.J., Shaheen, S.E., Ginley, D.S., (2006) J. Phys. Chem. B, 110, p. 3257Chang, Y.-M., Su, W.-F., Wang, L., (2008) Macromol. Rapid Commun., 29, p. 1303Cantu, M.L., Chafiq, A., Faissat, J., Valls, I.G., Yu, Y., (2011) Sol. Energy Mater. Sol. Cells, 95, p. 1362Jiang, K.-J., Manseki, K., Yu, Y.-H., Masaki, N., Suzuki, K., Suzuki, Y.-L., Yanagida, S., (2009) Adv. Funct. Mater., 19, p. 2481Goh, C., Scully, S.R., McGehee, M.D., (2007) J. Appl. Phys., 101, p. 114503Krüger, J., Bach, U., Grätzel, M., (2000) Adv. Mater., 12, p. 447Montanari, I., Nogueira, A.F., Nelson, J., Durrant, J.R., Winder, C., Loi, M.A., Sariciftci, N.S., Brabec, C., (2002) Appl. Phys. Lett., 81, p. 3001Nogueira, A.F., Montanari, I., Nelson, J., Brabec, C., Sariciftci, N.S., Durrant, J.R., (2003) J. Phys. Chem., 107, p. 1567Haque, S.A., Palomares, E., Cho, B.M., Green, A.N.M., Hirata, N., Klug, D.R., Durrant, J.R., (2005) J. Am. Chem. Soc., 127, p. 3456Clifford, J.N., Palomares, E., Nazeeruddin, M.K., Grätzel, M., Nelson, J., Li, X., Long, J., Durrant, J.R., (2004) J. Am. Chem. Soc., 126, p. 5225Bouclé, J., Chyla, S., Shaffer, M.S.P., Durrant, J.R., Bradley, D.D.C., Nelson, J., (2008) Adv. Funct. Mater., 18, p. 62

When is policing fair? Groups, identity and judgements of the procedural justice of coercive crowd policing

Procedural justice theory (PJT) is now a widely utilised theoretical perspective in policing research that acknowledges the centrality of police ‘fairness’. Despite its widespread acceptance this paper asserts that there are conceptual limitations that emerge when applying the theory to the policing of crowd events. This paper contends that this problem with PJT is a result of specific assumptions that are highlighted by two studies using a novel experimental approach. Study 1 systematically manipulated the social categories used to describe crowd participants subjected to police coercion. The experiment demonstrates how these social categories dramatically affected participants’ perceptions of the same police action and that it was participants’ relational identification with the police, rather than a superordinate category, that mediated the association between judgements of procedural fairness and intentions to cooperate. In Study 2, using a quasi-experimental design, we then replicated and extended these findings by demonstrating how perceptions of procedural fairness are also influenced by levels of in-group identification. The paper concludes by exploring the implications of the data for reconceptualising the social psychological processes mediating these judgements and impacts of police legitimacy

An extreme value theory approach to calculating minimum capital risk requirements

This paper investigates the frequency of extreme events for three LIFFE futures contracts for the calculation of minimum capital risk requirements (MCRRs). We propose a semiparametric approach where the tails are modelled by the Generalized Pareto Distribution and smaller risks are captured by the empirical distribution function. We compare the capital requirements form this approach with those calculated from the unconditional density and from a conditional density - a GARCH(1,1) model. Our primary finding is that both in-sample and for a hold-out sample, our extreme value approach yields superior results than either of the other two models which do not explicitly model the tails of the return distribution. Since the use of these internal models will be permitted under the EC-CAD II, they could be widely adopted in the near future for determining capital adequacies. Hence, close scrutiny of competing models is required to avoid a potentially costly misallocation capital resources while at the same time ensuring the safety of the financial system

Temporin L and aurein 2.5 have identical conformations but subtly distinct membrane and antibacterial activities

Frogs such as Rana temporaria and Litoria aurea secrete numerous closely related antimicrobial peptides (AMPs) as an effective chemical dermal defence. Damage or penetration of the bacterial plasma membrane is considered essential for AMP activity and such properties are commonly ascribed to their ability to form secondary amphipathic, α-helix conformations in membrane mimicking milieu. Nevertheless, despite the high similarity in physical properties and preference for adopting such conformations, the spectrum of activity and potency of AMPs often varies considerably. Hence distinguishing apparently similar AMPs according to their behaviour in, and effects on, model membranes will inform understanding of primary-sequence-specific antimicrobial mechanisms. Here we use a combination of molecular dynamics simulations, circular dichroism and patch-clamp to investigate the basis for differing anti-bacterial activities in representative AMPs from each species; temporin L and aurein 2.5. Despite adopting near identical, α-helix conformations in the steady-state in a variety of membrane models, these two AMPs can be distinguished both in vitro and in silico based on their dynamic interactions with model membranes, notably their differing conformational flexibility at the N-terminus, ability to form higher order aggregates and the characteristics of induced ion conductance. Taken together, these differences provide an explanation of the greater potency and broader antibacterial spectrum of activity of temporin L over aurein 2.5. Consequently, while the secondary amphipathic, α-helix conformation is a key determinant of the ability of a cationic AMP to penetrate and disrupt the bacterial plasma membrane, the exact mechanism, potency and spectrum of activity is determined by precise structural and dynamic contributions from specific residues in each AMP sequence

The Sudbury Neutrino Observatory

The Sudbury Neutrino Observatory is a second generation water Cherenkov detector designed to determine whether the currently observed solar neutrino deficit is a result of neutrino oscillations. The detector is unique in its use of D2O as a detection medium, permitting it to make a solar model-independent test of the neutrino oscillation hypothesis by comparison of the charged- and neutral-current interaction rates. In this paper the physical properties, construction, and preliminary operation of the Sudbury Neutrino Observatory are described. Data and predicted operating parameters are provided whenever possible.Comment: 58 pages, 12 figures, submitted to Nucl. Inst. Meth. Uses elsart and epsf style files. For additional information about SNO see http://www.sno.phy.queensu.ca . This version has some new reference

Novel genetic loci associated with hippocampal volume

The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal volume, four of them novel. Of the novel loci, three lie within genes (ASTN2, DPP4 and MAST4) and one is found 200 kb upstream of SHH. A hippocampal subfield analysis shows that a locus within the MSRB3 gene shows evidence of a localized effect along the dentate gyrus, subiculum, CA1 and fissure. Further, we show that genetic variants associated with decreased hippocampal volume are also associated with increased risk for Alzheimer's disease (rg =-0.155). Our findings suggest novel biological pathways through which human genetic variation influences hippocampal volume and risk for neuropsychiatric illness