Family history in the Aetiology of Gestational Diabetes Mellitus and Type 2 Diabetes

The aetiology of Type 2 diabetes [NIDDM] is assumed to involve a multiplicity of causal factors involving both genetic and environmental, including intrauterine, components. Aim: To identify the relationship of various aspects of family history and hence the possible role of genetic influence in the development of Type 2 DM in the Maltese population. Methods: The family history details of a study population undergoing an oGTT during pregnancy was assessed during pregnancy and at follow-up eight years postpartum. The findings were related to previous national epidemiological studies. Results: The study showed a definite statistical correlation between a maternal and sibling family history of diabetes with the onset of GDM/GIGT and later Type 2 DM. No such correlation was shown with a paternal or grandparent family history. Conclusions: The findings suggest that genetic factors are poor determinants for adult-onset GDM or Type 2 DM, the major role player being apparently alterations in the intrauterine environment of the fetus.peer-reviewe

Long-term significance of gestational carbohydrate intolerance : a longitudinal study

Severe forms of GDM have been conclusively associated with significantly increased risk of developing DM later on in life. The long-term significance of GIGT has not yet been definitely elucidated. The study was set up to compare the present carbohydrate metabolism status and anthropomorphic characteristics of women diagnosed as suffering from abnormal carbohydrate tolerance during pregnancy eight years previously with those recorded as having normal glucose tolerance. The prevalence of present abnormal glucose tolerance was significantly higher in women who had been noted to have carbohydrate intolerance during their pregnancy, the prevalence depending on the gestational severity (10.0% in normal glucose tolerance, 36.4% in borderline GIGT; 66.7% in GIGT). Women whose overweight or obese status persists or develops after their pregnancy were statistically more likely to develop abnormal glucose tolerance later on in life (11.9-12.5% in normal-overweight BMI, 38.2% in obese BMI). A maternal and sibling, but not paternal, family history of diabetes was also a statistically significant risk factor. GIGT appears to be a definite risk factor for the development of carbohydrate metabolism problems later on in life, this being related to the severity during pregnancy and the presence or development of obesity. It is proposed that women diagnosed to suffer from GIGT should be regularly monitored after the pregnancy, particularly if other risk factors such as obesity are also present.peer-reviewe

Realistic heterointerfaces model for excitonic states in growth-interrupted quantum wells

We present a model for the disorder of the heterointerfaces in GaAs quantum wells including long-range components like monolayer island formation induced by the surface diffusion during the epitaxial growth process. Taking into account both interfaces, a disorder potential for the exciton motion in the quantum well plane is derived. The excitonic optical properties are calculated using either a time-propagation of the excitonic polarization with a phenomenological dephasing, or a full exciton eigenstate model including microscopic radiative decay and phonon scattering rates. While the results of the two methods are generally similar, the eigenstate model does predict a distribution of dephasing rates and a somewhat modified spectral response. Comparing the results with measured absorption and resonant Rayleigh scattering in GaAs/AlAs quantum wells subjected to growth interrupts, their specific disorder parameters like correlation lengths and interface flatness are determined. We find that the long-range disorder in the two heterointerfaces is highly correlated, having rather similar average in-plane correlation lengths of about 60 and 90 nm. The distribution of dephasing rates observed in the experiment is in agreement with the results of the eigenstate model. Finally, we simulate highly spatially resolved optical experiments resolving individual exciton states in the deduced interface structure.Comment: To appear in Physical Review

Long-range spin-qubit interaction mediated by microcavity polaritons

We study the optically-induced coupling between spins mediated by polaritons in a planar micro-cavity. In the strong coupling regime, the vacuum Rabi splitting introduces anisotropies in the spin coupling. Moreover, due to their photon-like mass, polaritons provide an extremely long spin coupling range. This suggests the realization of two-qubit all-optical quantum operations within tens of picoseconds with spins localized as far as hundreds of nanometers apart.Comment: 5 pages, 3 figure

Spontaneous self-ordered states of vortex-antivortex pairs in a Polariton Condensate

Polariton condensates have proved to be model systems to investigate topological defects, as they allow for direct and non-destructive imaging of the condensate complex order parameter. The fundamental topological excitations of such systems are quantized vortices. In specific configurations, further ordering can bring the formation of vortex lattices. In this work we demonstrate the spontaneous formation of ordered vortical states, consisting in geometrically self-arranged vortex-antivortex pairs. A mean-field generalized Gross-Pitaevskii model reproduces and supports the physics of the observed phenomenology

Comment on : Zhu et al. Fasting Plasma Glucose at 24–28 Weeks to Screen for Gestational Diabetes Mellitus : New Evidence From China. Diabetes Care 2013; 36:2038–2040

The article by Zhu et al. published inDiabetes Care concludes that a fasting plasma glucose (FPG) at 24–28 weeks’ gestation can be used in low-resource regions as a screening test to identify gestational diabetes mellitus (GDM) in Chinese patients. However, in their experience, a screening protocol using FPG cutoff points of $4.4 and #5.0 mmol/L would fail to identify about 12% of the GDM cases and require a formal oral glucose tolerance test (OGTT) to be performed in about half of the pregnant population. These observations contrast with our findings in a circum-Mediterranean population.peer-reviewe

Direct evidence of reduced dynamic scattering in the lower polariton of a semiconductor microcavity

The temperature dependent linewidths of homogeneously broadened GaAs/AlxGa1-xAs microcavity polaritons are investigated. The linewidths of the lower, middle, and upper polariton resonances are measured directly from reflection spectra at normal incidence (k‖=0). The linewidth of the lower polariton is found to be smaller than the linewidths of the middle and upper polaritons at all investigated temperatures ranging from 11 to 100 K. The results clearly show the reduction of dynamic scattering processes in the lower polariton compared to the middle and upper polaritons, in agreement with theoretical predictions in literature. A nontrivial temperature dependence of the linewidth is found and its physical origin is discussed

History of leprosy in Malta

Abstract Leprosy was always viewed with aborrhence requiring segregation of the unfortunate sufferers. The policy of segregation in dedicated leprosaria, initially introduced during the Medieval Period, was re-adopted during the late 19 th century and persisted well into the 20 th century. The management of lepers in Malta followed similar principles as elsewhere

Strong compensation of the quantum fluctuation corrections in clean superconductor

The theory of fluctuation conductivity for an arbitrary impurity concentration including ultra-clean limit is developed. It is demonstrated that the formal divergency of the fluctuation density of states contribution obtained previously for the clean case is removed by the correct treatment of the non-local ballistic electron scattering. We show that in the ultra-clean limit ($T\tau \gg \sqrt{\frac{T_c}{T-T_c}}$) the density-of-states quantum corrections are canceled by the Maki-Thompson term and only quasi-classical paraconductivity remains.Comment: 7 pages 2 figure