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The electronic structure and optical properties of a series of iso-electronic and iso-structural CdSxSe1-x solid solution nanostructures have been investigated using X-ray absorption near edge structure, extended X-ray absorption fine structure, and X-ray excited optical luminescence at various absorption edges of Cd, S, and Se. It is found that the system exhibits compositions, with variable local structure in-between that of CdS and CdSe accompanied by tunable optical band gap between that of CdS and CdSe. Theoretical calculation using density functional theory has been carried out to elucidate the observations. It is also found that luminescence induced by X-ray excitation shows new optical channels not observed previously with laser excitation. The implications of these observations are discussed. [ABSTRACT FROM AUTHOR]

We use Hubble Space Telescope /Space Telescope Imaging Spectrograph long-slit G430M and G750M spectra to analyse the extended [O  iii ] λ5007 emission in a sample of 12 nearby (z < 0.12) luminous (L bol > 1.6 × 1045 erg s−1) QSO2s. The purpose of the study is to determine the properties of the mass outflows of ionized gas and their role in active galactic nucleus feedback. We measure fluxes and velocities as functions of radial distances. Using cloudy models and ionizing luminosities derived from [O  iii ] λ5007, we are able to estimate the densities for the emission-line gas. From these results, we derive masses of [O  iii ]-emitting gas, mass outflow rates, kinetic energies, kinetic luminosities, momenta, and momentum flow rates as a function of radial distance for each of the targets. For the sample, masses are several times |$10^{3}$| – |$10^{7}\, {\rm M_{\odot }}$| and peak outflow rates are from 9.3 × 10−3 to |$10.3\, {\rm M_{\odot }}\, {\rm yr^{-1}}$|⁠. The peak kinetic luminosities are (3.4 × 10−8)–(4.9 × 10−4) of the bolometric luminosity, which does not approach the (5.0 × 10−3)–(5.0 × 10−2) range required by some models for efficient feedback. For Mrk 34, which has the largest kinetic luminosity of our sample, in order to produce efficient feedback there would have to be 10 times more [O  iii ]-emitting gas than that we detected at its position of maximum kinetic luminosity. Three targets show extended [O  iii ] emission, but compact outflow regions. This may be due to different mass profiles or different evolutionary histories. [ABSTRACT FROM AUTHOR]

One common adverse effect following breast-conservation surgery and adjuvant radiation is lymphedema. While lymphedema of the arm has been well-characterized, there has been less investigation into lymphedema of the breast. We sought to characterize rates of breast lymphedema (BLE) in women with early-stage breast cancer and identify potential predictors in its development. Two hundred and thirty consecutive patients treated with lumpectomy and adjuvant whole breast radiation therapy (WBRT) from January 2016 - June 2017 were included. All patients were seen in our lymphedema monitoring clinic for baseline and at least one follow-up lymphedema measurement. BLE grades were assigned by trained nurses in the lymphedema clinic. Data regarding patient demographic and treatment factors were extracted from the electronic medical record. Comparisons between groups were made using Chi-Square analysis performed in SAS. The median age of the sample was 62 (range 31-90). Median follow-up from surgery was 15.3 months. Fortythree patients were diagnosed with lymphedema of the breast (18.7%). Rates of grade 1 and 2 BLE were 93% and 7%, respectively; there were no cases of severe lymphedema. Sixty-three percent of cases resolved by last follow-up with treatment recommendations. There was no association between development of BLE and patient factors investigated, including age, T stage, radiation dose and fractionation, lymph node biopsy, number of lymph nodes removed, development of arm lymphedema, and use of chemotherapy. Tumor subtype was found to be significant (P = 0.04) and there was a trend towards significance for receipt of trastuzumab (P = 0.09). BLE is a distinct entity from arm lymphedema and is a common finding in women treated with breast-conserving surgery and adjuvant WBRT. It is a generally mild and self-limiting process. There were no treatment or patient-related factors that correlated with increased risk of lymphedema development in our sample except for HER-2 positive disease and receipt of trastuzamab. [ABSTRACT FROM AUTHOR]

In the singular perturbation limit ε → 0, we analyse the linear stability of multi-spot patterns on a bounded 2-D domain, with Neumann boundary conditions, as well as periodic patterns of spots centred at the lattice points of a Bravais lattice in $\mathbb{R}^2$ , for the Brusselator reaction–diffusion model $$ \begin{equation*} v_t = \epsilon^2 \Delta v + \epsilon^2 - v + fu v^2 \,, \qquad \tau u_t = D \Delta u + \frac{1}{\epsilon^2}\left(v - u v^2\right) \,, \end{equation*} $$ where the parameters satisfy 0 < f < 1, τ > 0 and D > 0. A previous leading-order linear stability theory characterizing the onset of spot amplitude instabilities for the parameter regime D = ${\mathcal O}$ (ν−1), where ν = −1/log ϵ , based on a rigorous analysis of a non-local eigenvalue problem (NLEP), predicts that zero-eigenvalue crossings are degenerate. To unfold this degeneracy, the conventional leading-order-in-ν NLEP linear stability theory for spot amplitude instabilities is extended to one higher order in the logarithmic gauge ν. For a multi-spot pattern on a finite domain under a certain symmetry condition on the spot configuration, or for a periodic pattern of spots centred at the lattice points of a Bravais lattice in $\mathbb{R}^2$ , our extended NLEP theory provides explicit and improved analytical predictions for the critical value of the inhibitor diffusivity D at which a competition instability, due to a zero-eigenvalue crossing, will occur. Finally, when D is below the competition stability threshold, a different extension of conventional NLEP theory is used to determine an explicit scaling law, with anomalous dependence on ϵ , for the Hopf bifurcation threshold value of τ that characterizes temporal oscillations in the spot amplitudes. [ABSTRACT FROM AUTHOR]