Kinetic model of II-VI(001) semiconductor surfaces: Growth rates in atomic layer epitaxy

We present a zinc-blende lattice gas model of II-VI(001) surfaces, which is investigated by means of Kinetic Monte Carlo (KMC) simulations. Anisotropic effective interactions between surface metal atoms allow for the description of, e.g., the sublimation of CdTe(001), including the reconstruction of Cd-terminated surfaces and its dependence on the substrate temperature T. Our model also includes Te-dimerization and the potential presence of excess Te in a reservoir of weakly bound atoms at the surface. We study the self-regulation of atomic layer epitaxy (ALE) and demonstrate how the interplay of the reservoir occupation with the surface kinetics results in two different regimes: at high T the growth rate is limited to 0.5 layers per ALE cycle, whereas at low enough T each cycle adds a complete layer of CdTe. The transition between the two regimes occurs at a characteristic temperature and its dependence on external parameters is studied. Comparing the temperature dependence of the ALE growth rate in our model with experimental results for CdTe we find qualitative agreement.Comment: 9 pages (REVTeX), 8 figures (EPS). Content revised, references added, typos correcte

Value of sarcopenia in the resection of colorectal liver metastases—a systematic review and meta-analysis

IntroductionSarcopenia is defined as a decline in muscle function as well as muscle mass. Sarcopenia itself and sarcopenic obesity, defined as sarcopenia in obese patients, have been used as surrogates for a worse prognosis in colorectal cancer. This review aims to determine if there is evidence for sarcopenia as a prognostic parameter in colorectal liver metastases (CRLM).MethodsPubMed, Embase, Cochrane Central, Web of Science, SCOPUS, and CINAHL databases were searched for articles that were selected in accordance with the PRISMA guidelines. The primary outcomes were overall survival (OS) and disease-free survival (DFS). A random effects meta-analysis was conducted.ResultsAfter eliminating duplicates and screening abstracts (n = 111), 949 studies were screened, and 33 publications met the inclusion criteria. Of them, 15 were selected after close paper review, and 10 were incorporated into the meta-analysis, which comprised 825 patients. No significant influence of sarcopenia for OS (odds ratio (OR), 2.802 (95% confidence interval (CI), 1.094–1.11); p = 0.4) or DFS (OR, 1.203 (95% CI, 1.162–1.208); p = 0.5) was found, although a trend was defined toward sarcopenia. Sarcopenia significantly influenced postoperative complication rates (OR, 7.905 (95% CI, 1.876–3.32); p = 0.001) in two studies where data were available.ConclusionExisting evidence on the influence of sarcopenia on postoperative OS as well as DFS in patients undergoing resection for CRLM exists. We were not able to confirm that sarcopenic patients have a significantly worse OS and DFS in our analysis, although a trend toward this hypothesis was visible. Sarcopenia seems to influence complication rates but prospective studies are needed

Binding Energy of Charged Excitons in ZnSe-based Quantum Wells

Excitons and charged excitons (trions) are investigated in ZnSe-based quantum well structures with (Zn,Be,Mg)Se and (Zn,Mg)(S,Se) barriers by means of magneto-optical spectroscopy. Binding energies of negatively () and positively (X+) charged excitons are measured as functions of quantum well width, free carrier density and in external magnetic fields up to 47 T. The binding energy of shows a strong increase from 1.4 to 8.9 meV with decreasing quantum well width from 190 to 29 A. The binding energies of X+ are about 25% smaller than the binding energy in the same structures. The magnetic field behavior of and X+ binding energies differ qualitatively. With growing magnetic field strength, increases its binding energy by 35-150%, while for X+ it decreases by 25%. Zeeman spin splittings and oscillator strengths of excitons and trions are measured and discussed

Optical Method for Determination of Carrier Density in Modulation Doped Quantum Wells

An optical method is suggested to determine the concentration of two-dimensional electrons in modulation-doped quantum wells at low and moderate electron densities between 10^{9} and 2x10^{11} cm^{-2}. The method is based on an analysis of magneto-reflectivity spectra of charged excitons (trions). The circular polarization degree and the oscillator strength of the charged excitons contain information about the density and spin polarization of two-dimensional electron gas. The method is applied to CdTe/(Cd,Mg)Te and ZnSe/Zn,Mg)(S,Se) heterostructures

Treatment of Open-Angle Glaucoma and Ocular Hypertension with Preservative-Free Tafluprost/Timolol Fixed-Dose Combination Therapy : The VISIONARY Study

Funding Information: Funding was provided by Santen SA for the study, medical writing services and Rapid Service Fees. All authors had full access to all of the data in this study and take complete responsibility for the integrity of the data and accuracy of the data analysis. The contribution of IRCCS Fondazione Bietti to this work was supported by the Italian Ministry of Health and by Fondazione Roma. Publisher Copyright: © 2020, The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Introduction: A non-interventional, multicenter, European, prospective evaluation of the effectiveness, tolerability, and safety of a topical preservative-free tafluprost (0.0015%) and timolol (0.5%) fixed-dose combination (PF tafluprost/timolol FC) in adults with open-angle glaucoma (OAG) and ocular hypertension (OHT) demonstrating insufficient response to topical beta-receptor blockers or prostaglandin analogue (PGA) monotherapy. Methods: Mean intraocular pressure (IOP) change from baseline was measured at study visits following a switch to PF tafluprost/timolol FC. Primary endpoint was absolute mean IOP change at month 6. Change from baseline concerning ocular signs and symptoms was also explored. Results: Analyses included 577 patients (59.6% female). Mean age (SD) was 67.8 (11.67) years. Mean (SD) IOP reduction from baseline was significant at all study visits; 5.4 (3.76) mmHg (23.7%) at week 4, 5.9 (3.90) mmHg (25.6%) at week 12, and 5.7 (4.11) mmHg (24.9%) at month 6 (p < 0.0001 for all visits). At month 6, 69.2%, 53.6%, 40.0%, and 25.8% were responders based on ≥ 20%, ≥ 25%, ≥ 30%, and ≥ 35% cutoff values for mean IOP, respectively. Significant reductions were observed concerning corneal fluorescein staining (p < 0.0001), dry eye symptoms, irritation, itching, and foreign body sensation (p < 0.001 for each parameter). Conjunctival hyperemia was significantly reduced at all study visits (p < 0.0001 at each visit). Overall, 69 treatment-related adverse events (AEs) were reported, one of which was serious (status asthmaticus). Most AEs were mild to moderate in severity, and the majority had resolved or were resolving at the end of the study period. Conclusion: In clinical practice, PF tafluprost/timolol FC provided statistically and clinically significant IOP reductions in patients with OAG and OHT insufficiently controlled on or intolerant to PGA or beta-receptor blocker monotherapy. The full IOP reduction appeared at week 4 and was maintained over the 6-month study period. Key symptoms of ocular surface health improved. Trial Registration: European Union electronic Register of Post-Authorisation Studies (EU PAS) register number, EUPAS22204.publishersversionPeer reviewe

β1-integrins signaling and mammary tumor progression in transgenic mouse models: implications for human breast cancer

Consistent with their essential role in cell adhesion to the extracellular matrix, integrins and their associated signaling pathways have been shown to be involved in cell proliferation, migration, invasion and survival, processes required in both tumorigenesis and metastasis. β1-integrins represent the predominantly expressed integrins in mammary epithelial cells and have been proven crucial for mammary gland development and differentiation. Here we provide an overview of the studies that have used transgenic mouse models of mammary tumorigenesis to establish β1-integrin as a critical mediator of breast cancer progression and thereby as a potential therapeutic target for the development of new anticancer strategies