Ultrafast nonlocal control of spontaneous emission

Solid-state cavity quantum electrodynamics systems will form scalable nodes of future quantum networks, allowing the storage, processing and retrieval of quantum bits, where a real-time control of the radiative interaction in the cavity is required to achieve high efficiency. We demonstrate here the dynamic molding of the vacuum field in a coupled-cavity system to achieve the ultrafast nonlocal modulation of spontaneous emission of quantum dots in photonic crystal cavities, on a timescale of ~200 ps, much faster than their natural radiative lifetimes. This opens the way to the ultrafast control of semiconductor-based cavity quantum electrodynamics systems for application in quantum interfaces and to a new class of ultrafast lasers based on nano-photonic cavities.Comment: 15 pages, 4 figure

Compensated right ventricular function of the onset of pulmonary hypertension in a rat model depends on chamber remodeling and contractile augmentation.

Right-ventricular function is a good indicator of pulmonary arterial hypertension (PAH) prognosis; however, how the right ventricle (RV) adapts to the pressure overload is not well understood. Here, we aimed at characterizing the time course of RV early remodeling and discriminate the contribution of ventricular geometric remodeling and intrinsic changes in myocardial mechanical properties in a monocrotaline (MCT) animal model. In a longitudinal study of PAH, ventricular morphology and function were assessed weekly during the first four weeks after MCT exposure. Using invasive measurements of RV pressure and volume, heart performance was evaluated at end of systole and diastole to quantify contractility (end-systolic elastance) and chamber stiffness (end-diastolic elastance). To distinguish between morphological and intrinsic mechanisms, a computational model of the RV was developed and used to determine the level of prediction when accounting for wall masses and unloaded volume measurements changes. By four weeks, mean pulmonary arterial pressure and elastance rose significantly. RV pressures rose significantly after the second week accompanied by significant RV hypertrophy, but RV stroke volume and cardiac output were maintained. The model analysis suggested that, after two weeks, this compensation was only possible due to a significant increase in the intrinsic inotropy of RV myocardium. We conclude that this MCT-PAH rat is a model of RV compensation during the first month after treatment, where geometric remodeling on EDPVR and increased myocardial contractility on ESPVR are the major mechanisms by which stroke volume is preserved in the setting of elevated pulmonary arterial pressure. The mediators of this compensation might themselves promote longer-term adverse remodeling and decompensation in this animal model

Satellites and large doping- and temperature-dependence of electronic properties in hole-doped BaFe2As2

Over the last years, superconductivity has been discovered in several families of iron-based compounds. Despite intense research, even basic electronic properties of these materials, such as Fermi surfaces, effective electron masses, or orbital characters are still subject to debate. Here, we address an issue that has not been considered before, namely the consequences of dynamical screening of the Coulomb interactions among Fe-d electrons. We demonstrate its importance not only for correlation satellites seen in photoemission spectroscopy, but also for the low-energy electronic structure. From our analysis of the normal phase of BaFe2As2 emerges the picture of a strongly correlated compound with strongly doping- and temperature-dependent properties. In the hole overdoped regime, an incoherent metal is found, while Fermi-liquid behavior is recovered in the undoped compound. At optimal doping, the self-energy exhibits an unusual square-root energy dependence which leads to strong band renormalizations near the Fermi level

Understanding factors associated with the translation of cardiovascular research: A multinational case study approach

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited.This article has been made available through the Brunel Open Access Publishing Fund.Background: Funders of health research increasingly seek to understand how best to allocate resources in order to achieve maximum value from their funding. We built an international consortium and developed a multinational case study approach to assess benefits arising from health research. We used that to facilitate analysis of factors in the production of research that might be associated with translating research findings into wider impacts, and the complexities involved. Methods: We built on the Payback Framework and expanded its application through conducting co-ordinated case studies on the payback from cardiovascular and stroke research in Australia, Canada and the United Kingdom. We selected a stratified random sample of projects from leading medical research funders. We devised a series of innovative steps to: minimize the effect of researcher bias; rate the level of impacts identified in the case studies; and interrogate case study narratives to identify factors that correlated with achieving high or low levels of impact. Results: Twenty-nine detailed case studies produced many and diverse impacts. Over the 15 to 20 years examined, basic biomedical research has a greater impact than clinical research in terms of academic impacts such as knowledge production and research capacity building. Clinical research has greater levels of wider impact on health policies, practice, and generating health gains. There was no correlation between knowledge production and wider impacts. We identified various factors associated with high impact. Interaction between researchers and practitioners and the public is associated with achieving high academic impact and translation into wider impacts, as is basic research conducted with a clinical focus. Strategic thinking by clinical researchers, in terms of thinking through pathways by which research could potentially be translated into practice, is associated with high wider impact. Finally, we identified the complexity of factors behind research translation that can arise in a single case. Conclusions: We can systematically assess research impacts and use the findings to promote translation. Research funders can justify funding research of diverse types, but they should not assume academic impacts are proxies for wider impacts. They should encourage researchers to consider pathways towards impact and engage potential research users in research processes. © 2014 Wooding et al.; licensee BioMed Central Ltd.RAND Europe and HERG, with subsequent funding from the NHFA, the HSFC and the CIHR. This research was also partially supported by the Policy Research Programme in the English Department of Health

The utilisation of health research in policy-making: Concepts, examples and methods of assessment

The importance of health research utilisation in policy-making, and of understanding the mechanisms involved, is increasingly recognised. Recent reports calling for more resources to improve health in developing countries, and global pressures for accountability, draw greater attention to research-informed policy-making. Key utilisation issues have been described for at least twenty years, but the growing focus on health research systems creates additional dimensions. The utilisation of health research in policy-making should contribute to policies that may eventually lead to desired outcomes, including health gains. In this article, exploration of these issues is combined with a review of various forms of policy-making. When this is linked to analysis of different types of health research, it assists in building a comprehensive account of the diverse meanings of research utilisation. Previous studies report methods and conceptual frameworks that have been applied, if with varying degrees of success, to record utilisation in policy-making. These studies reveal various examples of research impact within a general picture of underutilisation. Factors potentially enhancing utilisation can be identified by exploration of: priority setting; activities of the health research system at the interface between research and policy-making; and the role of the recipients, or 'receptors', of health research. An interfaces and receptors model provides a framework for analysis. Recommendations about possible methods for assessing health research utilisation follow identification of the purposes of such assessments. Our conclusion is that research utilisation can be better understood, and enhanced, by developing assessment methods informed by conceptual analysis and review of previous studies

Extrinsic and intrinsic determinants of nerve regeneration

After central nervous system (CNS) injury axons fail to regenerate often leading to persistent neurologic deficit although injured peripheral nervous system (PNS) axons mount a robust regenerative response that may lead to functional recovery. Some of the failures of CNS regeneration arise from the many glial-based inhibitory molecules found in the injured CNS, whereas the intrinsic regenerative potential of some CNS neurons is actively curtailed during CNS maturation and limited after injury. In this review, the molecular basis for extrinsic and intrinsic modulation of axon regeneration within the nervous system is evaluated. A more complete understanding of the factors limiting axonal regeneration will provide a rational basis, which is used to develop improved treatments for nervous system injury

The Significance of Hair for Face Recognition

Hair is a feature of the head that frequently changes in different situations. For this reason much research in the area of face perception has employed stimuli without hair. To investigate the effect of the presence of hair we used faces with and without hair in a recognition task. Participants took part in trials in which the state of the hair either remained consistent (Same) or switched between learning and test (Switch). It was found that in the Same trials performance did not differ for stimuli presented with and without hair. This implies that there is sufficient information in the internal features of the face for optimal performance in this task. It was also found that performance in the Switch trials was substantially lower than in the Same trials. This drop in accuracy when the stimuli were switched suggests that faces are represented in a holistic manner and that manipulation of the hair causes disruption to this, with implications for the interpretation of some previous studies

Carotid bruits as predictor for carotid stenoses detected by ultrasonography: an observational study

<p>Abstract</p> <p>Background</p> <p>Carotid surgery in asymptomatic subjects with carotid stenosis is effective to prevent ischemic stroke. There is, however, uncertainty how to find such persons at risk, because mass screening with carotid artery ultrasonography (US) is not cost-effective. Signs of carotid bruits corresponding to the carotid arteries may serve as a tool to select subjects for further investigation. This study is thus aimed at determining the usefulness of carotid bruits in the screening of carotid stenoses.</p> <p>Methods</p> <p>1555 consecutive carotid ultrasonography investigations from 1486 cases done between January 2004 and March 2006 at Norrlands University Hospital, Sweden, were examined. 356 subjects, medium age 69 (27–88) years, had a significant (≥ 50%) US-verified carotid stenosis uni- or bilaterally, 291 had been examined for signs of carotid bruits. The likelihood ratios for carotid bruits to predict US-verified carotid stenoses were calculated and expressed as likelihood percentages.</p> <p>Results</p> <p>Thirty-one out of 100 persons (31%) with carotid bruit as an indication to perform carotid US had a significant (≥ 50%) carotid stenosis. 281 of the 356 (79%) cases with significant carotid stenoses were found among patients with cerebrovascular disease (CVD). 145 of 226 (64%) CVD patients with a significant carotid stenosis had a carotid bruit. In patients with 50–99% carotid stenoses carotid bruits had an accuracy of 75% (436/582), a sensitivity of 71% (236/334), a specificity of 81% (200/248), a positive likelihood ratio at 3.65 and a negative likelihood at 0.36. Patients with 70–99% stenoses had the highest sensitivity at 77% (183/238). In patients with 100% carotid stenoses, carotid bruits had a sensitivity of 26% (15/57) and a specificity of 49% (256/525).</p> <p>Conclusion</p> <p>Although carotid bruits are not accurate to confirm or to exclude significant carotid stenoses, these signs are appropriate for directed screening for further investigation with carotid US if the patient lacks contraindications for surgery. Lack of carotid bruits in CVD patients does not exclude a carotid stenosis.</p

The influence of semantic and phonological factors on syntactic decisions: An event-related brain potential study

During language production and comprehension, information about a word's syntactic properties is sometimes needed. While the decision about the grammatical gender of a word requires access to syntactic knowledge, it has also been hypothesized that semantic (i.e., biological gender) or phonological information (i.e., sound regularities) may influence this decision. Event-related potentials (ERPs) were measured while native speakers of German processed written words that were or were not semantically and/or phonologically marked for gender. Behavioral and ERP results showed that participants were faster in making a gender decision when words were semantically and/or phonologically gender marked than when this was not the case, although the phonological effects were less clear. In conclusion, our data provide evidence that even though participants performed a grammatical gender decision, this task can be influenced by semantic and phonological factors