The Role of Families in Shaping Youth Social Participation: Evidence from Singapore

Youth participation in social groups is important in developing skills and experience for successful transition to adulthood. What kinds of families do youth who are active in social groups and who take on leadership positions come from? Using data from the National Youth Survey 2005, this research studies the social participation of Singaporean youth aged 15 -18. Through probit regression analysis, it examines how youth participation in Singapore is associated with two types of family characteristics. First, it examines the role of maternal education. As a proxy for social class, maternal education represents the roles of cultural capital formation and concerted involvement by middle class parents. Second, it studies the role of family challenge and support. Maternal education is found to predict both high participation and leadership. While additional family challenge induces greater participation, family support increases participation only when the level of support is high.youth participation; family challenge; family support; social class

Filmwise condensation on micro-fin surfaces produced by selective laser melting

This paper presents an experimental investigation on the condensation of steam on vertical flat surfaces with arrays of micro-fins. Three micro-fin surfaces (MF1, MF2 and MF3) of the same fin diameter and fin height but with different fin pitch were fabricated by selective laser melting. The surfaces were tested in a condensation chamber where the gravity driven condensate flow and vapor velocity are orthogonal to one another. The effects of fin pitch and vapor velocity on the heat transfer performances of the surfaces were examined. Our results suggest that fin pitch has significant influence on the condensate drainage path as compared to the increase in heat transfer area. In addition, above a certain wall subcooled temperature, the increase in vapor velocity also resulted in the systematic increase in condensation heat flux indicating the significant effects of vapor shear force. In all, up to 1.4 times enhancement in the heat transfer coefficient was achieved with the micro-fin surface with a fin pitch of 300 μm as compared to a plain Al-6061 surface at constant vapor velocity.Papers presented at the 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portoroz, Slovenia on 17-19 July 2017 .International centre for heat and mass transfer.American society of thermal and fluids engineers

Enhanced thermal performance of a water-cooled cold plate with porous inserts fabricated by selective laser melting

The paper presents an experimental investigation of the thermal and hydraulic performance of a new class of porous metallic foams with ordered arrangements of the Rhombi-Octet unit cell design for use in a water-cooled cold plate. Selective laser melting (SLM) was employed to fabricate the porous metallic foams of two different unit cell sizes. A closed-loop chilled water test facility was set up to perform the experimental investigation and the results of the SLM fabricated porous metallic foams were compared with those of a commercially available metallic foam of random tetrakaidecahedron-like unit cell structures. The permeability (K) and inertia coefficient (CE) of the various metallic foams were characterized using the Forchheimer-extended Darcy equation and it was determined that K can be enhanced by 3.3 times with an increase in unit cell size of the Rhombi-Octet design from 5 mm to 10 mm. In addition, the Rhombi-Octet metallic foam insert also exhibits up to 91% enhancement in the heat transfer coefficient (have) as compared to the empty channel cold plate and up to 47% as compared to the commercial metallic foam insert.Papers presented at the 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portoroz, Slovenia on 17-19 July 2017 .International centre for heat and mass transfer.American society of thermal and fluids engineers

Exactly solvable path integral for open cavities in terms of quasinormal modes

We evaluate the finite-temperature Euclidean phase-space path integral for the generating functional of a scalar field inside a leaky cavity. Provided the source is confined to the cavity, one can first of all integrate out the fields on the outside to obtain an effective action for the cavity alone. Subsequently, one uses an expansion of the cavity field in terms of its quasinormal modes (QNMs)-the exact, exponentially damped eigenstates of the classical evolution operator, which previously have been shown to be complete for a large class of models. Dissipation causes the effective cavity action to be nondiagonal in the QNM basis. The inversion of this action matrix inherent in the Gaussian path integral to obtain the generating functional is therefore nontrivial, but can be accomplished by invoking a novel QNM sum rule. The results are consistent with those obtained previously using canonical quantization.Comment: REVTeX, 26 pages, submitted to Phys. Rev.

Intracranial Metastatic Melanoma

Central nervous system (CNS) metastases are a common manifestation of malignant melanoma, with a median overall survival of as little as 4.7 months based on a study of patients diagnosed between 1986 and 2004 prior to the era of effective systemic therapy. Yet most of the clinical trials exclude patients with intra-cranial metastases. CNS involvement often causes neurological deficits and functional impairment. Localised therapies, such as surgical excision and stereotactic radiotherapy are applicable to only a minority of patients. There are evidences of clinical benefits for immunotherapy than best supportive care and when given alongside radiotherapy provides a better overall survival than radiotherapy alone. This chapter evaluates the efficacy and toxicity of these treatments against advanced melanoma patients with brain metastases

Energy related public environmental concerns and intra-firm pay gap in polluting enterprises: Evidence from China

YesThis study empirically investigates the impact of energy related public environmental concerns on the pay gap within polluting companies. It uses the extreme environmental event of the PM2.5 surge at the end of 2011, which led to an upsurge in energy related public environmental concerns in China, as a quasi-natural experiment. According to our findings, energy related public environmental concerns lead to a significant increase in the executive–employee pay gap of polluting companies compared to that of non-polluting companies, owing to a significant increase in executive compensation and no significant change in employee income. The effect of energy related public environmental concerns on increasing the pay gap within polluting companies is more significant in samples with high agency costs, poor information transparency, less analyst follow-up, and fewer institutional investors' shareholding. Furthermore, as energy related public environmental concerns exacerbate the polluting firms' internal pay gap, their total factor productivity and investment efficiency fall significantly. In summary, energy related public environmental concerns not only widen the wage gap within polluting enterprises but also worsen their operational and investment efficiency, which has important policy implications for emerging market economies seeking to balance environmental protection and economic development.The authors wew funded by NSFC number (71903199), Fujian Pro vincial Federation of Social Sciences (FJ2023BF045), Guangdong Phi losophy and Social Sciences Project (GD23XYJ08), the Innovation and Talent Base for Digital Technology and Finance (B21038), and "the Fundamental Research Funds for the Central Universities", Zhongnan Univeristy of Economics and Law (2722023EJ002)

Geometrically Tailored Skyrmions at Zero Magnetic Field in Multilayered Nanostructures

Magnetic skyrmions are chiral spin structures recently observed at room temperature in multilayer films. Their topological stability will enable high scalability in confined geometries—a sought-after attribute for device applications. Despite numerous theoretical studies examining sub-100-nm Néel skyrmions in nanostructures, in practice their ambient stability and evolution with confinement and their magnetic parameters remain to be established. Here we present the zero-field stabilization of sub-100-nm room-temperature Néel-textured skyrmions confined in Ir/Fe(x)/Co(y)/Pt nanodots over a wide range of magnetic and geometric parameters. The zero-field skyrmion size, here as small as approximately 50 nm, can be tailored by a factor of 4 with variation of dot size and magnetic interactions. Crucially, skyrmions with differing thermodynamic stability exhibit an unexpected dichotomy in confinement phenomenologies. These results establish skyrmion phenomenology in multilayer nanostructures, and prompt the synergistic use of magnetic and geometric parameters to achieve desired properties in devices

A high performance dye-sensitized solar cell with a novel nanocomposite film of PtNP/MWCNT on the counter electrode

An imide-functionalized material, poly(oxyethylene)-segmented polymer, was synthesized from the reaction of poly(oxyethylene) diamine of 2000 g mol(-1) M(w) and 4,4'-oxydiphthalic anhydride and used to disperse hybrid nanomaterials of platinum nanoparticles and multi-wall carbon nanotubes (PtNP/MWCNT). The composite material was spin-coated into film and further prepared as the counter electrode (PtNP/MWCNT-CE) for a dye-sensitized solar cell (DSSC). The short-circuit current density (J(SC)) and power-conversion efficiency (eta) of the DSSC with PtNP/MWCNT-CE were found to be 18.01 +/- 0.91 mA cm(-2) and 8.00 +/- 0.23%, respectively, while the corresponding values were 14.62 +/- 0.19 mA cm(-2) and 6.92 +/- 0.07% for a DSSC with a bare platinum counter electrode (Pt-CE). The presence and distribution of PtNP/MWCNT on the CE were characterized by using scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The attachment of PtNPs on MWCNTs was observed by transmission electron microscopy (TEM). Cyclic voltammetry (CV), incident-photo-to-current efficiency (IPCE) and electrochemical impedance spectra (EIS) were correlated to explain the efficacy of this nanocomposite system

Oseltamivir- and Amantadine-Resistant Influenza Viruses A (H1N1)

Surveillance of amantadine and oseltamivir resistance among influenza viruses was begun in Hong Kong in 2006. In 2008, while both A/Brisbane/59/2007-like and A/Hong Kong/2652/2006-like viruses (H1N1) were cocirculating, we detected amantadine and oseltamivir resistance among A/Hong Kong/2652/2006-like viruses (H1N1), caused by genetic reassortment or spontaneous mutation