Time Series Tests of Income Convergence with Two Structural Breaks: An Update and Extension

This paper uses newly available long-span data on real per capita incomes from 1900-2001 to test for stochastic convergence in a diverse group of 29 countries. To perform our tests, we utilize the two-break LM unit root test of Lee and Strazicich (2003) and endogenously determine two distinct structural breaks in level and trend for each country. Despite including both OECD and non-OECD countries, we find significant evidence that incomes are stochastically converging. World War II is the most often identified time period of breaks. The results represent slightly more evidence in favor of convergence than reported in the study by Dawson and Sen (forthcoming) using the same sample of countries.

Mechanism of enhanced light output in InGaN-based microlight emitting diodes

Micro-light emitting diode (LED) arrays with diameters of 4 to 20 mum have been fabricated and were found to be much more efficient light emitters compared to their broad-area counterparts, with up to five times enhancement in optical power densities. The possible mechanisms responsible for the improvement in performance were investigated. Strain relaxation in the microstructures as measured by Raman spectroscopy was not observed, arguing against theories of an increase in internal quantum efficiency due to a reduction of the piezoelectric field put forward by other groups. Optical microscope images show intense light emission at the periphery of the devices, as a result of light scattering off the etched sidewalls. This increases the extraction efficiency relative to broad area devices and boosts the forward optical output. In addition, spectra of the forward emitted light reveal the presence of resonant cavity modes [whispering gallery (WG) modes in particular] which appear to play a role in enhancing the optical output

Health promotion interventions to prevent early childhood human influenza at the household level: A realist review to identify implications for programmes in Hong Kong

© 2014 John Wiley & Sons Ltd. Aims and objectives: To identify factors affecting the delivery of health promotion interventions to prevent early childhood human influenza at the household level. Background: Yearly, influenza epidemics seriously affect all age groups, particularly those with weakened immune systems, including children. Influenza is transmitted easily from person to person through droplet and direct contact. Maintaining personal hygiene, avoiding close contact with the infected person and proper hand washing are recommended as the most effective means of preventing the transmission of influenza. However, it is not clear what programme-related mechanisms and contexts are crucial to the successful delivery of interventions in the home. This study systematically reviewed published research studies to identify factors influencing the effective delivery of health promotion programmes targeting influenza in a household. Design: Realist review. Methods: A realist review methodology was selected to examine what interventions are effective in preventing and managing influenza at the household level and in what circumstances. A structured search of the peer-reviewed primary research literature was undertaken using a defined search protocol. Results: Eight studies were retrieved for the analysis. Mechanisms impacting on intervention delivery were identified, including timing of implementation, programme reach, organisational and healthcare worker involvement, mode and place of delivery, contact with infected person, health practice compliance and sustainability at home. Conclusion: These findings suggest contextual factors that could be identified through ecological approaches to health promotion that are crucial for policymakers to consider when designing interventions. Relevance to clinical practice: The active involvement of community nurses through an integrated household visiting programme may help to better deliver family-based health promotion interventions to prevent illnesses such as influenza in children

The approaches Hong Kong Chinese mothers adopt to teach their preschool children to prevent influenza: A multiple case study at household level

© 2016 The Author(s). Background: In Hong Kong, the population is at risk of seasonal influenza infection twice a year. Seasonal influenza is significantly associated with the increased hospitalization of children. Maintaining personal hygiene and vaccination are the most effective measures to prevent influenza infection. Research demonstrates a positive relationship between the health practices applied by parents and the behaviour of their children highlighting the importance of parental heath education. However, there is minimal research that provides an understanding of how Hong Kong Chinese parents teach their children to prevent seasonal influenza. Methods: Mixed methods research was undertaken that employed a multiple-case study approach to gain an understanding of parental teaching practices regarding seasonal influenza prevention. Purposive intensity sampling was adopted to recruit twenty parents and their healthy children. A thematic analysis was employed to examine the qualitative interview data and the quantitative survey data were examined descriptively. These data were then integrated to provide a more rigorous understanding of parental teaching strategies. Comparisons were made across cases to reveal commonalities and differences. Results: Five major themes were identified: processes parents used to teach personal hygiene; parent-child interaction during teaching; approaches to managing children's health behaviours; enhancing children's healthy practices; and parents' perspective of the role of the nurse in health promotion. Conclusions: This study provided valuable insight into the approach of Hong Kong Chinese parents in teaching their children to prevent seasonal influenza. The results indicate that parents can be better supported to develop effective strategies to teach their preschool children hygiene practices for seasonal influenza prevention. Partnerships with community nurses can play a role in building effective parent-child interactions to enhance children's learning and adoption of healthy practices

InGaN nano-ring structures for high-efficiency light emitting diodes

A technique based on the Fresnel diffraction effect for the fabrication of nano-scale site-controlled ring structures in InGaN/GaN multi-quantum well structures has been demonstrated. The ring structures have an internal diameter of 500 nm and a wall width of 300 nm. A 1 cm-1 Raman shift has been measured, signifying substantial strain relaxation from the fabricated structure. The 9 nm blueshift observed in the cathodoluminescence spectra can be attributed to band filling and/or screening of the piezoelectric field. A light emitting diode based on this geometry has been demonstrated

The role of culture in relation to the seasonal influenza prevention practices of Hong Kong Chinese parents with preschool children

© 2017 Institute of Health Promotion and Education. Aims and objectives: To explore the role of culture in the seasonal influenza prevention practices of Hong Kong Chinese parents with a healthy preschool child. Background: Cultural values and norms significantly influence parents’ health preventive practices and related health promotion strategies. Most research is concerned with influenza prevention and focuses on the factors affecting vaccination uptake, the use of facemasks and effective hand hygiene. There is limited research exploring the influence of culture on the seasonal influenza prevention practices of parents with a young child in Hong Kong. Design: Mixed methods using a multiple-case study approach. Methods: Purposive intensity sampling was employed to recruit 20 parents with children under five years old. A thematic analysis was employed to examine the qualitative interview data and the quantitative data were analysed descriptively. The data were then integrated to provide a more rigorous comprehension of parents’ cultural seasonal influenza preventive practices. Comparisons were conducted across the 20 cases and patterns examined. Results: Five themes were identified. They were sharing beds; boiling white vinegar to kill air-born germs; diet therapy to enhance health; self-prescribed Chinese medication to manage a child’s cold symptoms; and the co-use of Western and traditional Chinese medications to prevent seasonal influenza. Conclusions: The findings indicate that a pluralistic approach to health promotion should be considered to ensure the likelihood that families accept, support and comply with health advice in seasonal influenza prevention. The delivery of culturally appropriate health promotion requires a close partnership between nurses and parents

Discovery of the supernova remnant G351.0-5.4

Context. While searching the NRAO VLA Sky Survey (NVSS) for diffuse radio emission, we have serendipitously discovered extended radio emission close to the Galactic plane. The radio morphology suggests the presence of a previously unknown Galactic supernova remnant. An unclassified {\gamma}-ray source detected by EGRET (3EG J1744-3934) is present in the same location and may stem from the interaction between high-speed particles escaping the remnant and the surrounding interstellar medium. Aims. Our aim is to confirm the presence of a previously unknown supernova remnant and to determine a possible association with the {\gamma}-ray emission 3EG J1744-3934. Methods. We have conducted optical and radio follow-ups of the target using the Dark Energy Camera (DECam) on the Blanco telescope at Cerro Tololo Inter-American Observatory (CTIO) and the Giant Meterwave Radio Telescope (GMRT). We then combined these data with archival radio and {\gamma}-ray observations. Results. While we detected the extended emission in four different radio bands (325, 1400, 2417, and 4850 MHz), no optical counterpart has been identified. Given its morphology and brightness, it is likely that the radio emission is caused by an old supernova remnant no longer visible in the optical band. Although an unclassified EGRET source is co-located with the supernova remnant, Fermi-LAT data do not show a significant {\gamma}-ray excess that is correlated with the radio emission. However, in the radial distribution of the {\gamma}-ray events, a spatially extended feature is related with SNR at a confidence level $\sim 1.5$ {\sigma}. Conclusions. We classify the newly discovered extended emission in the radio band as the old remnant of a previously unknown Galactic supernova: SNR G351.0-5.4.Comment: 6 pages, 6 figures, accepted A&

Marked expansion of exocrine and endocrine pancreas with incretin therapy in humans with increased exocrine pancreas dysplasia and the potential for glucagon-producing neuroendocrine tumors.

Controversy exists regarding the potential regenerative influences of incretin therapy on pancreatic β-cells versus possible adverse pancreatic proliferative effects. Examination of pancreata from age-matched organ donors with type 2 diabetes mellitus (DM) treated by incretin therapy (n = 8) or other therapy (n = 12) and nondiabetic control subjects (n = 14) reveals an ∼40% increased pancreatic mass in DM treated with incretin therapy, with both increased exocrine cell proliferation (P < 0.0001) and dysplasia (increased pancreatic intraepithelial neoplasia, P < 0.01). Pancreata in DM treated with incretin therapy were notable for α-cell hyperplasia and glucagon-expressing microadenomas (3 of 8) and a neuroendocrine tumor. β-Cell mass was reduced by ∼60% in those with DM, yet a sixfold increase was observed in incretin-treated subjects, although DM persisted. Endocrine cells costaining for insulin and glucagon were increased in DM compared with non-DM control subjects (P < 0.05) and markedly further increased by incretin therapy (P < 0.05). In conclusion, incretin therapy in humans resulted in a marked expansion of the exocrine and endocrine pancreatic compartments, the former being accompanied by increased proliferation and dysplasia and the latter by α-cell hyperplasia with the potential for evolution into neuroendocrine tumors

Information requirements for guidance and control systems

Control or guidance system performance dependency on information handling by subsystem

Resummation Effects in Vector-Boson and Higgs Associated Production

Fixed-order QCD radiative corrections to the vector-boson and Higgs associated production channels, pp -> VH (V=W, Z), at hadron colliders are well understood. We combine higher order perturbative QCD calculations with soft-gluon resummation of both threshold logarithms and logarithms which are important at low transverse momentum of the VH pair. We study the effects of both types of logarithms on the scale dependence of the total cross section and on various kinematic distributions. The next-to-next-to-next-to-leading logarithmic (NNNLL) resummed total cross sections at the LHC are almost identical to the fixed-order perturbative next-to-next-to-leading order (NNLO) rates, indicating the excellent convergence of the perturbative QCD series. Resummation of the VH transverse momentum (p_T) spectrum provides reliable results for small values of p_T and suggests that implementing a jet-veto will significantly decrease the cross sections.Comment: 25 pages, references update