Tunnel spectroscopy in ac-driven quantum dot nanoresonators

Electronic transport in a triple quantum dot shuttle device in the presence of an ac field is analyzed within a fully quantum mechanical framework. A generalized density matrix formalism is used to describe the time evolution for electronic state occupations in a dissipative phonon bath. In the presence of an ac gate voltage, the electronic states are dressed by photons and the interplay between photon and vibrational sidebands produces current characteristics that obey selection rules. Varying the ac parameters allows to tune the tunneling current features. In particular, we show that coherent destruction of tunneling can be achieved in our device

Transient tunneling effects of resonance doublets in triple barrier systems

Transient tunneling effects in triple barrier systems are investigated by considering a time-dependent solution to the Schr\"{o}dinger equation with a cutoff wave initial condition. We derive a two-level formula for incidence energies $E$ near the first resonance doublet of the system. Based on that expression we find that the probability density along the internal region of the potential, is governed by three oscillation frequencies: one of them refers to the well known Bohr frequency, given in terms of the first and second resonance energies of the doublet, and the two others, represent a coupling with the incidence energy $E$. This allows to manipulate the above frequencies to control the tunneling transient behavior of the probability density in the short-time regim

Antibacterial effect of four endodontic cements against Enterococcus faecalis ATCC 29212. An in vitro study.

Abstract: Objective: To compare the in vitro antibacterial effect of the root canal cements Endobalsam®, Top Seal®, Apexit® and Endofill® against Enterococcus faecalis ATCC 29212. Materials and method: Eighty-five applications of cements on Enterococcus faecalis, cultured in vitro on solid media in Petri dishes, were analyzed. Five groups were evaluated: four for each cement, and the fifth for the positive control (amoxicillin). The antibacterial effect was measured by the diameters of the bacterial inhibition halos at 24 hours, 48 hours, and seven days. Student´s t-test, ANOVA and the Tukey test were used for the statistical analysis. Results: No statistically significant differences were found at 24 hours (p>0.05); at 48 hours and seven days, Endofill and Apexit® had the greatest effect (p<0.05); finally, on  day 7 only Endofill® showed an effect similar to the positive control (p>0.05). Conclusion: Enterococcus faecalis ATCC 29212 was susceptible to all cements. Endofill® had greater in vitro antibacterial effect than Apexit®, Top Seal® and Endobalsam®

Systematic Review of Neovascular Age-Related Macular Degeneration Disease Activity Criteria Use to Shorten, Maintain or Extend Treatment Intervals with Anti-VEGF in Clinical Trials: Implications for Clinical Practice

Introduction: Clinical trials in neovascular age-related macular degeneration (nAMD) using anti-vascular endothelial growth factor (ant-VEGF) injections use disease activity (DA) criteria to shorten, maintain or increase the interval between injections. Differences in these DA criteria may contribute to differences in the proportions of patients with macular fluid at key time points or achieving extended dosing intervals in these trials. We identified, collated and evaluated DA criteria from pivotal anti-VEGF nAMD trials to understand how differences impact on these studies and real-world visual acuity and extending dosing outcomes. Methods: This was a systematic review of literature on Pubmed for randomised clinical trials in nAMD using a proactive treatment regimen. We excluded case reports, review articles and studies on fewer than 50 participants. Results: Twelve clinical trials (LUCAS, VIEW, TREX-AMD, FLUID, TREND, RIVAL, ALTAIR, CANTREAT, ARIES, TREX-Conbercept, HAWK & HARRIER, TENAYA & LUCERNE) investigating anti-VEGF treatment of nAMD were identified according to our search strategy. Different studies utilised a different combination of DA criteria. Specifically, six trials included visual acuity change; four included macular thickness change; one included visual acuity change if associated with macular thickness change; one with qualitative optical coherence tomography (OCT) features; four with qualitative OCT features if also associated with visual acuity change; 10 with macular haemorrhage and five with other fluorescein angiographic features. Conclusion: Different clinical trials use different DA criteria when altering the interval between anti-VEGF injections. This makes it difficult to draw meaningful conclusions about secondary outcomes such as proportion of patients treated at extended dosing intervals or proportions of eyes with persistent subretinal or intraretinal fluid. Standardising DA criteria in clinical trials and preferentially using those easily applied in a real-world setting would lead to results more achievable in real-world settings and for a meaningful comparison of treatment durability