3,287 research outputs found
He then said..: Understudied deviations from V2 in Early Germanic
ABSTRACT This paper discusses a V3-pattern in Early Germanic that has so far not been considered independently. In this construction, a clause-initial XP is followed by the adverbial element OHG do/OE þa/OS tho (lit. ‘then’), which is directly followed by the finite verb. Based on a pilot study of the OHG translation of Tatian’s gospel harmony and the OE Blickling Homilies, it is shown that the pattern exhibits slightly different properties in OE and OHG. In OHG, the element preceding do is usually a pronominal shifting topic, while in OE, the clause-initial XP may also be a full DP that is either a shifting topic or a continuing topic. To account for these differences between OE and OHG, we argue that OE þa is first-merged as the head of a clause-medial projection that serves to mark the boundary between the topic and the focus domain. In contrast, OHG do (and OS tho) is a topic marker that is either part of the fronted shifting topic, or base-generated as a head in the left clausal periphery. As to its internal syntax, we propose a grammaticalization path for do/þa/tho in which a demonstrative adverb first turns into an adverbial discourse marker that may also serve expletive functions before it eventually grammaticalizes into the topic particle addressed in this paper
A correlational analysis of the relationships among intolerance of uncertainty, anxiety sensitivity, subjective sleep quality, and insomnia symptoms
In this study, we used structural equation modeling to investigate the interplay among Intolerance of Uncertainty (IU), Anxiety Sensitivity (AS), and sleep problems. Three hundred undergraduate students completed the Intolerance of Uncertainty Scale, the Intolerance of Uncertainty Inventory, the Anxiety Sensitivity Index, the Beck Depression Inventory, the State-Trait Anxiety Inventory, the Pittsburgh Sleep Quality Index and the Insomnia Severity Index. 68% and 40% of the students reported poor sleep quality or sub-threshold insomnia problems, respectively. Depression and anxiety levels were above the cut-off for about one-fourth of the participants. Structural equation modeling revealed that IU was strongly associated with AS, in turn influencing both insomnia severity and sleep quality via depression and anxiety. Significant indirect effects revealed that an anxious pathway was more strongly associated with insomnia severity, while a depression pathway was more relevant for worsening the quality of sleep. We discussed the results in the frameworks of cognitive models of insomnia. Viewing AS and IU as antecedents of sleep problems and assigning to AS a pivotal role, our study suggested indications for clinical interventions on a population at risk for sleep disorders
Experimental Determination of Momentum-Resolved Electron-Phonon Coupling
We provide a novel experimental method to quantitatively estimate the
electron-phonon coupling and its momentum dependence from resonant inelastic
x-ray scattering (RIXS) spectra based on the detuning of the incident photon
energy away from an absorption resonance. We apply it to the cuprate parent
compound NdBaCuO and find that the electronic coupling to the
oxygen half-breathing phonon mode is strongest at the Brillouin zone boundary,
where it amounts to eV, in agreement with previous studies. In
principle, this method is applicable to any absorption resonance suitable for
RIXS measurements and will help to define the contribution of lattice
vibrations to the peculiar properties of quantum materials.Comment: 6 pages, 3 figure
2D perovskite stabilized phase-pure formamidinium perovskite solar cells.
Compositional engineering has been used to overcome difficulties in fabricating high-quality phase-pure formamidinium perovskite films together with its ambient instability. However, this comes alongside an undesirable increase in bandgap that sacrifices the device photocurrent. Here we report the fabrication of phase-pure formamidinium-lead tri-iodide perovskite films with excellent optoelectronic quality and stability. Incorporation of 1.67 mol% of 2D phenylethylammonium lead iodide into the precursor solution enables the formation of phase-pure formamidinium perovskite with an order of magnitude enhanced photoluminescence lifetime. The 2D perovskite spontaneously forms at grain boundaries to protect the formamidinium perovskite from moisture and suppress ion migration. A stabilized power conversion efficiency (PCE) of 20.64% (certified stabilized PCE of 19.77%) is achieved with a short-circuit current density exceeding 24 mA cm-2 and an open-circuit voltage of 1.130 V, corresponding to a loss-in-potential of 0.35 V, and significantly enhanced operational stability
Flashback Avoidance in Swirling Flow Burners
AbstractLean premixed combustion using swirling flows is widely used in gas turbines and combustion. Although flashback is not generally a problem with natural gas combustion, there are some reports of flashback damage with existing gas turbines, whilst hydrogen enriched fuel blends cause concerns in this area. Thus, this paper describes a practical approach to study and avoid flashback in a pilot scale 100kW tangential swirl burner. The flashback phenomenon is studied experimentally via the derivation of flashback limits for a variety of different geometrical conditions. A high speed camera is used to visualize the process and distinguish new patterns of avoidance. The use of a central fuel injector is shown to give substantial benefits in terms of flashback resistance. Conclusions are drawn as to mitigation technologies
The Creation of Puffin, the Automatic Uncertainty Compiler
An uncertainty compiler is a tool that automatically translates original computer source code lacking explicit uncertainty analysis into code containing appropriate uncertainty representations and uncertainty propagation algorithms. We have developed an prototype uncertainty compiler along with an associated object-oriented uncertainty language in the form of a stand-alone Python library. It handles the specifications of input uncertainties and inserts calls to intrusive uncertainty quantification algorithms in the library. The uncertainty compiler can apply intrusive uncertainty propagation methods to codes or parts of codes and therefore more comprehensively and flexibly address both epistemic and aleatory uncertainties
Towards an automatic uncertainty compiler
An uncertainty compiler is a tool that automatically translates original computer source code lacking explicit uncertainty quantification into code containing appropriate uncertainty representations and uncertainty propagation algorithms. It handles the specifications of input uncertainties, and inserts calls to intrusive uncertainty quantification algorithms. In theory, one could create an uncertainty compiler for any scientific programming language. The uncertainty compiler can apply intrusive uncertainty propagation methods to codes or parts of codes and, therefore, more comprehensively and flexibly address epistemic and aleatory uncertainties. This paper explores the concept and the practicalities of creating such a compiler
Perovskite-polymer composite cross-linker approach for highly-stable and efficient perovskite solar cells.
Manipulation of grain boundaries in polycrystalline perovskite is an essential consideration for both the optoelectronic properties and environmental stability of solar cells as the solution-processing of perovskite films inevitably introduces many defects at grain boundaries. Though small molecule-based additives have proven to be effective defect passivating agents, their high volatility and diffusivity cannot render perovskite films robust enough against harsh environments. Here we suggest design rules for effective molecules by considering their molecular structure. From these, we introduce a strategy to form macromolecular intermediate phases using long chain polymers, which leads to the formation of a polymer-perovskite composite cross-linker. The cross-linker functions to bridge the perovskite grains, minimizing grain-to-grain electrical decoupling and yielding excellent environmental stability against moisture, light, and heat, which has not been attainable with small molecule defect passivating agents. Consequently, all photovoltaic parameters are significantly enhanced in the solar cells and the devices also show excellent stability
A wide field-of-view, modular, high-density diffuse optical tomography system for minimally constrained three-dimensional functional neuroimaging
The ability to produce high-quality images of human brain function in any environment and during unconstrained movement of the subject has long been a goal of neuroimaging research. Diffuse optical tomography, which uses the intensity of back-scattered near-infrared light from multiple source-detector pairs to image changes in haemoglobin concentrations in the brain, is uniquely placed to achieve this goal. Here, we describe a new generation of modular, fibre-less, high-density diffuse optical tomography technology that provides exceptional sensitivity, a large dynamic range, a field-of-view sufficient to cover approximately one-third of the adult scalp, and also incorporates dedicated motion sensing into each module. Using in-vivo measures, we demonstrate a noise-equivalent power of 318 fW, and an effective dynamic range of 142 dB. We describe the application of this system to a novel somatomotor neuroimaging paradigm that involves subjects walking and texting on a smartphone. Our results demonstrate that wearable high-density diffuse optical tomography permits three-dimensional imaging of the human brain function during overt movement of the subject; images of somatomotor cortical activation can be obtained while subjects move in a relatively unconstrained manner, and these images are in good agreement with those obtained while the subjects remain stationary. The scalable nature of the technology we described here paves the way for the routine acquisition of high-quality, three-dimensional, whole-cortex diffuse optical tomography images of cerebral haemodynamics, both inside and outside of the laboratory environment, which has profound implications for neuroscience
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