Inhibited spontaneous emission of quantum dots observed in a 3D photonic band gap

We present time-resolved emission experiments of semiconductor quantum dots in silicon 3D inverse-woodpile photonic band gap crystals. A systematic study is made of crystals with a range of pore radii to tune the band gap relative to the emission frequency. The decay rates averaged over all dipole orientations are inhibited by a factor of 10 in the photonic band gap and enhanced up to 2? outside the gap, in agreement with theory. We discuss the effects of spatial inhomogeneity, nonradiative decay, and transition dipole orientations on the observed inhibition in the band gap.Comment: 5 figures, update author lis

Virtual-pion and two-photon production in pp scattering

Two-photon production in pp scattering is proposed as a means of studying virtual-pion emission. Such a process is complementary to real-pion emission in pp scattering. The virtual-pion signal is embedded in a background of double-photon bremsstrahlung. We have developed a model to describe this background process and show that in certain parts of phase space the virtual-pion signal gives significant contribution. In addition, through interference with the two-photon bremsstrahlung background, one can determine the relative phase of the virtual-pion process

Serial intravascular ultrasound assessment of changes in coronary atherosclerotic plaque dimensions and composition: an update

This manuscript reviews the use of serial intravascular ultrasound (IVUS) examination of coronary atherosclerosis in recent observational studies and randomized trials that revealed the effects of cholesterol-lowering and lipid-modifying therapies and offered novel insight into plaque progression and regression. We discuss the value of plaque progression–regression as complementary imaging endpoint and potential surrogate marker of cardiovascular event risk. In addition, the progress in serial assessment of coronary plaque composition and plaque vulnerability by radiofrequency-based analyses is reviewed. Finally, we report on the evaluation of true vessel remodelling in recent serial IVUS trials and discuss the future perspective of serial invasive imaging of coronary atherosclerosis

Higher education reform and the landscape diversity of higher education institutions in the Kyrgyz Republic, 1991–2015

Following its independence from the Soviet Union in 1991, Kyrgyzstan experienced processes of change across all areas of social, political and economic life. Higher education reform has been central to this agenda, and between 1991 and today the Soviet-era system of state-funded and Communist Party controlled higher education institutions (HEIs) in Kyrgyzstan has been transformed into an expansive, diverse, unequal, semi-privatized and marketized higher education (HE) landscape. Mindful of arguments that the marketization of higher education does not necessarily generate institutional diversification, that government regulation does not necessarily lead to homogenization among institutions, and that universities’ own institutional strategies and responses to environmental changes shape processes of structural reform in complex ways, this paper assesses the specific character of these changes to the higher education landscape in post-Soviet Kyrgyzstan. After briefly describing the structure and financing of higher education in the Kirgiz Soviet Socialist Republic from 1917–1991, we consider some key factors which have shaped patterns of the differentiation and diversification of HE in the post-Soviet period. These include the historical legacies of Soviet HE infrastructures, new legal and political frameworks for HE governance and finance, changes to regulations for the licensing of institutions and academic credentials, the introduction of new multinational policy agendas for higher education in the Central Asian region, changes in the relationship between higher education and labor, the introduction of a national university admissions examination, and the adoption of certain principles of the European Bologna Process. The picture of HE reform that emerges from this analysis is one in which concurrent processes of diversification and homogenization are not driven wholly by either state regulation or forces of market competition, but mediated by universities’ strategic negotiations of these forces in the context of historical institutional formations in Kyrgyzstan

Trends in Frailty and Its Association With Mortality:Results From the Longitudinal Aging Study Amsterdam, 1995-2016

The aim of this study was to investigate trends in frailty and its relationship with mortality among older adults aged 64-84 years across a period of 21 years. We used data from 1995 to 2016 from the Longitudinal Aging Study Amsterdam. A total of 7,742 observations of 2,874 respondents in the same age range (64-84 years) across 6 measurement waves were included. Frailty was measured with a 32-item frailty index, with a cutpoint of ≥0.25 to indicate frailty. The outcome measure was 4-year mortality. Generalized estimating equation analyses showed that among older adults aged 64-84 years the 4-year mortality rate declined between 1995 and 2016, while the prevalence of frailty increased. Across all measurement waves, frailty was associated with 4-year mortality (odds ratio = 2.79, 95% confidence interval: 2.39, 3.26). There was no statistically significant interaction effect between frailty and time on 4-year mortality, indicating a stable association between frailty and mortality. In more recent generations of older adults, frailty prevalence rates were higher, while excess mortality rates of frailty remained the same. This is important information for health policy-makers and clinical practitioners, showing that continued efforts are needed to reduce frailty and its negative health consequences

Single-center versus multi-center biparametric MRI radiomics approach for clinically significant peripheral zone prostate cancer

Contains fulltext : 239809.pdf (Publisher’s version ) (Open Access

Development of a thermal ionizer as ion catcher

An effective ion catcher is an important part of a radioactive beam facility that is based on in-flight production. The catcher stops fast radioactive products and emits them as singly charged slow ions. Current ion catchers are based on stopping in He and H$_2$ gas. However, with increasing intensity of the secondary beam the amount of ion-electron pairs created eventually prevents the electromagnetic extraction of the radioactive ions from the gas cell. In contrast, such limitations are not present in thermal ionizers used with the ISOL production technique. Therefore, at least for alkaline and alkaline earth elements, a thermal ionizer should then be preferred. An important use of the TRI$\mu$P facility will be for precision measurements using atom traps. Atom trapping is particularly possible for alkaline and alkaline earth isotopes. The facility can produce up to 10$^9$ s$^{-1}$ of various Na isotopes with the in-flight method. Therefore, we have built and tested a thermal ionizer. An overview of the operation, design, construction, and commissioning of the thermal ionizer for TRI$\mu$P will be presented along with first results for $^{20}$Na and $^{21}$Na.Comment: 10 pages, 4 figures, XVth International Conference on Electromagnetic Isotope Separators and Techniques Related to their Applications (EMIS 2007