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We aim to establish relative importance of socioeconomic, demographic, geographic and other determinants of national suicide rates. To this aim, we apply Bayesian model averaging (BMA) approach to a dataset of 27 potential determinants in a cross-section of 173 countries. Life expectancy at birth, ambient temperature, age dependency ratio and religious affiliation were found to be the most robust protective factors. Life expectancy at age 65 and unemployment rate are the most robust determinants that are positively associated with suicide mortality. [ABSTRACT FROM AUTHOR]

Plasmon nanoantennas are extensively used with molecular systems for chemical and biological ultra-sensing, for boosting the molecular emissive and energy transfer properties, for nanoscale catalysis, and for building advanced hybrid nanoarchitectures. In this perspective, we focus on the latest developments of using plasmon nanoantennas for nanoscale chiral chemistry and for advancing molecular magnetism. We overview the decisive role nanoplasmonics and nano-optics can play in achieving chirally selective molecular synthesis and separation and the way such processes might be precisely controlled by potentially merging chirality and magnetism at the molecular scale. We give our view on how these insights might lead to the emergence of exciting new fundamental concepts in nanoscale materials science.

This Perspective surveys the state-of-the-art and future prospects of science and technology employing nanoconfined light (nanophotonics and nanoplasmonics) in combination with magnetism. We denote this field broadly as nanoscale magnetophotonics. We include a general introduction to the field and describe the emerging magneto-optical effects in magnetoplasmonic and magnetophotonic nanostructures supporting localized and propagating plasmons. Special attention is given to magnetoplasmonic crystals with transverse magnetization and the associated nanophotonic non-reciprocal effects and to magneto-optical effects in periodic arrays of nanostructures. We also give an overview of the applications of these systems in biological and chemical sensing, as well as in light polarization and phase control. We further review the area of nonlinear magnetophotonics, the semiconductor spin-plasmonics, and the general principles and applications of opto-magnetism and nano-optical ultrafast control of magnetism and spintronics. [ABSTRACT FROM AUTHOR]

Optical polaritons appear when a material excitation strongly couples to an optical mode. Such strong coupling between molecular transitions and optical cavities results in far‐reaching opportunities in modifying fundamental properties of chemical matter. More recently an exciting prospect of self‐coupled polaritons has emerged by matter sustaining the optical mode with its geometry. Here, it is shown how strong coupling of the interband transition and surface plasmons can be engineered in nickel at the nanoscale to realize self‐coupled plasmon–interband polaritons inside metals. Using electron energy‐loss spectroscopy, it is demonstrated that in nickel thin films and nanoantennas the propagation and radiation losses result in a broadening of the plasmon linewidth and a transition from strong to weak coupling. Further, higher‐order plasmon resonances couple to the interband transition, and the multipolar‐coupled states acquire the field profile of the plasmon. The results provide a fundamental understanding of plasmon–interband coupling in metals and establish the base for the design of photocatalytic and magneto‐optical nanosystems. [ABSTRACT FROM AUTHOR]

We present a compact platform for biochemosensing based on the combination of a vertical-cavity surface-emitting laser (VCSEL) light source, microelectromechanical systems (MEMS)-based microoptics, a specially designed nanoplasmonic sensing chip, and charge-coupled device (CCD) detector. The platform does not require any spectral analyzer for signal evaluation, showing good promise for facile integration, neither does it use any microscope setup for the signal collection or imaging. The analytical capabilities of the developed biochemosensing platform are demonstrated by evaluation of the protein-substrate (biotinylated bovine serum albumin-gold) and the protein-protein (biotin--NeulrAvidin) binding kinetics, which is further compared to detection based on conventional optical extinction spectroscopy. The instrument is able to detect low femtomoles of adsorbed proteins with the limit of detection comparable to the state-of-the-art research and commercial optical label-free biochemosensors. 10.1021/ac9025169

The rational design of nanoporous two-dimensional supramolecular structures by the hierarchical assembly of organic molecules and transition metal atoms at surfaces is demonstrated. From primary components secondary mononuclear chiral complexes are formed, which represent antecedents for tertiary polynuclear metal-organic nanogrids.

Nanophotonic chiral antennas exhibit orders of magnitude higher circular dichroism (CD) compared to molecular systems. When the structural chirality is merged with magnetism at the nanoscale, efficient magnetic control over the dichroic response is achieved, bringing exciting prospects to active nanophotonic devices. Here, we devise macroscopic enantiomeric magnetophotonic metasurfaces of plasmonic-ferromagnetic spiral antennas assembled on large areas via hole-mask colloidal lithography. The simultaneous presence of 3D- and 2D-features in chiral nanoantennas induces large CD response, where we identify reciprocal and non-reciprocal contributions, respectively. Exploring further this type of magnetophotonic metasurfaces might allow the realization of high-sensitivity chiral sensors and prompts the design of advanced macroscopic optical devices operating with polarized light. [ABSTRACT FROM AUTHOR]

An ab initio theoretical analysis for an exemplary metal-organic coordination networks (MOCN) is reported, which was modeled using density functional theory (DFT) calculations. An indepth theoretical investigation is presented of a 2D-metal-organic coordination network comprising functional carboxylate-bridged diiron units.

Single-molecule level STM observations of chiral complexes generated by the assembly of achiral components and metal centers at a metal surface are reported. The findings indicate that a square planar ML(sub 4) complex can be chiral in two dimensions when symmetric bidentate ligands are employed which link to the metal atom in an organized unidentate fashion.

We report on the fabrication, integration, and simulation, both optical and optoelectrical, of two-dimensional photonic nanostructures for advanced light trapping in thin crystalline silicon (c-Si) solar cells. The photonic nanostructures are fabricated by the combination of various lithography (nanoimprint, laser interference, and hole mask colloidal) and etching (dry plasma and wet chemical) techniques. The nanopatterning possibilities thus range from periodic to random corrugations and from inverted nanopyramids to high aspect ratio profiles. Optically, the nanopatterning results in better performance than the standard pyramid texturing, showing a more robust behavior with respect to light incidence angle. Electrically, wet etching results in higher minority carrier lifetimes compared to dry etching. From the integration of the photonic nanostructures into a micron-thin c-Si solar cell certain factors limiting the efficiencies are identified. More precisely: (a) the parasitic absorption is limiting the short circuit current, (b) the conformality of thin-film coatings on the nanopatterned surface is limiting the fill factor, and (c) the material damage from dry etching is limiting the open circuit voltage. From optical simulations, the optimal pattern parameters are identified. From optoelectrical simulations, cell design considerations are discussed, suggesting to position the junction on the opposite side of the nanopattern. [ABSTRACT FROM AUTHOR]

Magnetoplasmonics is an emerging field of intense research on materials combining magnetic and plasmonic functionalities. The novel optical and magneto-optical (MO) properties displayed by these materials could allow the design of a new class of magnetically controllable optical nano-devices. In this work, we investigate the effects of a non-absorbing (insulating) substrate on the MO activity of pure ferromagnetic disk-shaped nanostructures supporting localized plasmon resonances. We show that the red-shift of the localized plasmon resonance, related to the modification of the localization of the electromagnetic field due to the substrate, is not the only effect that the substrate has on the MO response. We demonstrate that the reflectivity of the substrate itself plays a key role in determining the MO response of the system. We discuss why it is so and provide a description of the modeling tools suitable to take into account both effects. Understanding the role of the substrate will permit a more aware design of magnetoplasmonic nanostructured devices for future biotechnological and optoelectronic applications. Ferromagnetic nickel nanodisk in vacuum (left) and on a non-absorbing substrate (right), illuminated by linearly polarized light. The polarization of the reflected field is changed in the first case due to a combination of intrinsic magneto-optical properties and the nanoconfinement of the material. In the second case, the polarization of the reflected light is affected also by the presence of the substrate. [ABSTRACT FROM AUTHOR]

This article focuses on the empirical approach proposed by Hall and Jones (1999) to estimate the effect of what they call ‘social infrastructure’ on productivity across countries. We consider the issue of weak identification in their linear instrumental variables model. The evidence obtained from partially robust estimators, such as the k-class and jackknife estimators, is interpreted on the basis of Monte Carlo studies. Our findings suggest that using certain k-class estimators allows exclusive reliance on the linguistic variables to instrument for institutional quality despite their low correlation with the endogenous regressor in question. [ABSTRACT FROM PUBLISHER]

A strategy and implementation for efficiency enhancement of optimized high performance organic solar cells by a plasmonic nanostructured Ag rear electrode is presented. This enhancement is achieved by tuning the surface plasmon resonance of the nanostructures to the active layer absorption tail, which generates enhanced absorption by light scattering, as verified by experiment and simulation. [ABSTRACT FROM AUTHOR]

Two-country, one-good business cycle models with Cobb–Douglas preferences predict procyclical net exports. The opposite is observed in the data. We show that introduction of preferences that eliminate wealth effects on labour supply remedies this discrepancy. It also improves the model's ability in matching cross-country correlations. [ABSTRACT FROM AUTHOR]

Theoretically, two-country real business cycle models with time-separable preferences and complete markets predict that cross-country investment correlations will be negative. The opposite is true in the data. This phenomenon has been described by Backus et al. [in Cooley (ed.), Frontiers of Business Cycle Research, pp. 331–356 (Princeton, NJ: Princeton University Press, 1995)] as a quantity anomaly. This paper proposes to address this discrepancy by allowing the nonseparability of preferences over time. Here, we incorporate internal habit formation into consumption. Our model predicts the empirically plausible value of cross-country investment correlation without sacrificing other business cycle statistics. The results are robust to the degree of spillovers and persistence in the specification of the productivity shocks. [ABSTRACT FROM PUBLISHER]

Magnetic atoms at surfaces are a rich model system for solid-state magnetic bits exhibiting either classical or quantum behaviour. Individual atoms, however, are difficult to arrange in regular patterns. Moreover, their magnetic properties are dominated by interaction with the substrate, which, as in the case of Kondo systems, often leads to a decrease or quench of their local magnetic moment. Here, we show that the supramolecular assembly of Fe and 1,4-benzenedicarboxylic acid molecules on a Cu surface results in ordered arrays of high-spin mononuclear Fe centres on a 1.5 nm square grid. Lateral coordination with the molecular ligands yields unsaturated yet stable coordination bonds, which enable chemical modification of the electronic and magnetic properties of the Fe atoms independently from the substrate. The easy magnetization direction of the Fe centres can be switched by oxygen adsorption, thus opening a way to control the magnetic anisotropy in supramolecular layers akin to that used in metallic thin films. [ABSTRACT FROM AUTHOR]

We demonstrate the rational design of nanoporous two-dimensional supramolecular structures by the hierarchical assembly of organic molecules and transition metal atoms at surfaces. Single-molecule level observations with scanning tunneling microscopy monitor the successive aufbau of structures with increasing complexity. From the primary components secondary mononuclear chiral complexes are formed, which represent antecedents for tertiary polynuclear metal-organic nanogrids. These nanogrids represent the constituents of the eventually evolving two-dimensional networks comprising homochiral nanocavity arrays. Our findings visualize the evolution of complex matter in an exemplary way: from per se achiral species via chiral intermediates to mesoscale dissymmetric structures. [ABSTRACT FROM AUTHOR]

In this ‘focus on’ collection, a snapshot of the new, fast emerging field of magnetoplasmonics is presented. The research in the field deals with the combination of plasmonics and magnetism to elucidate the fundamentals of spin--plasmon interactions and reach new functionalities such as the enhancement of magneto-optical activity in various materials, active control of plasmons with weak magnetic fields, magnetoplasmonics-based bio- and chemical sensing, magnetophotonic and magnetoplasmonic crystals as modulators of light transmission and reflection, and many others. [ABSTRACT FROM AUTHOR]