54 research outputs found
On the action of the complete Brans-Dicke theory
Recently the most general completion of Brans-Dicke theory was appeared with
energy exchanged between the scalar field and ordinary matter, given that the
equation of motion for the scalar field keeps the simple wave form of
Brans-Dicke. This class of theories contain undetermined functions, but there
exist only three theories which are unambiguously determined from consistency.
Here, for the first such theory, it is found the action of the vacuum theory
which arises as the limit of the full matter theory. A symmetry transformation
of this vacuum action in the Jordan frame is found which consists of a
conformal transformation of the metric together with a redefinition of the
scalar field. Since the general family of vacuum theories is parametrized by an
arbitrary function of the scalar field, the action of this family is also
found. As for the full matter theory it is only found the action of the system
when the matter Lagrangian vanishes on-shell, as for example for pressureless
dust. Due to the interaction, this matter Lagrangian is non-minimally coupled
either in the Jordan or the Einstein frame.Comment: To appear in EPJC; minor change
Money and Information in a New Neoclassical Synthesis Framework
We consider an (otherwise standard) New Neoclassical Synthesis theoretical framework that allows a role for money. Money in our model has an informational role which consists in facilitating the estimation of the unobserved shocks that drive potential output and thus the state of the economy. For this purpose we estimate a small-scale sticky price model using Bayesian techniques. Our findings support the view that money has information value. This is reflected in higher precision in terms of unobserved model concepts such as the natural rate of output. Moreover, our results highlight how modelling money demand can provide insights about structural features of the economy that may be important for the design of interest rate rules. Focusing on money also allows for a step towards resolving the price puzzle. Money demand shocks can confound monetary policy shocks to generate a perverse price response in vector autoregressions (VAR).DSGE models, New Keynesian models, Money Monetary Policy, Bayesian analysis.
Money and Information in a New Neoclassical Synthesis Framework
We consider an (otherwise standard) New Neoclassical Synthesis theoretical framework that allows a role for money. Money in our model has an informational role which consists in facilitating the estimation of the unobserved shocks that drive potential output and thus the state of the economy. For this purpose we estimate a small-scale sticky price model using Bayesian techniques. Our findings support the view that money has information value. This is reflected in higher precision in terms of unobserved model concepts such as the natural rate of output. Moreover, our results highlight how modelling money demand can provide insights about structural features of the economy that may be important for the design of interest rate rules. Focusing on money also allows for a step towards resolving the price puzzle. Money demand shocks can confound monetary policy shocks to generate a perverse price response in vector autoregressions (VAR).DSGE models; New Keynesian models; Money; Monetary Policy; Bayesian analysis
Cover Picture: Ann. Phys. 2'2018
In article number 1700256, Emanuele Verrelli and coāworkers propose that cluster beam deposition of subā2nm magic number Au clusters, Au20 and Au55, on flat surfaces reveals a rich evolution of the phenomena taking place at substrate level. New magic number clusters have been formed via coalescence of neighbouring clusters, such as Au561. Experimental and simulation results reveal that neighbouring clusters on the substrate coalesce only when the distance from their nearest neighbour cluster is below a critical mark of 0.5 nm
Measles pneumonitis
Measles is an acute febrile illness, potentially fatal and highly contagious, which is transmitted through the respiratory mode. Fevercombined with one of the following: cough, coryza, conjunctivitis are the first manifestations of the disease. Koplikās spots mayalso appear on the buccal mucosa providing an opportunity to set the diagnosis even before the emergence of rash. Rash typicallyappears 3ā4 days after the onset of fever, initially on the face and behind the ears, and its appearance is associated with the peakof the symptoms. Measles affects multiple systems, including the respiratory system, with pneumonia being one of the most lethalcomplications. Management involves best supportive care, correction of dehydration and nutritional deficiencies, treatment ofsecondary bacterial infections and provision of vitamin A. Importantly, given that measles present with lifelong immunity followinginfection or vaccination, prevention through measles vaccination has a cardinal role for measlesā elimination. Indeed, public educationand vaccination led to an estimated 79% decrease in global measles deaths from 2000 to 2015. Nonetheless, the last two years haveseen a measles outbreak in several countries, partially due to the anti-vaccination movement. This article aims to present two casesof measles in our hospital and highlight the pressing need for vaccination in order to eradicate a potentially fatal disease
Telex: Principled System Support for Write-Sharing in Collaborative Applications
The Telex system is designed for sharing mutable data in a distributed
environment, particularly for collaborative applications. Users operate on
their local, persistent replica of shared documents; they can work disconnected
and suffer no network latency. The Telex approach to detect and correct
conflicts is application independent, based on an action-constraint graph (ACG)
that summarises the concurrency semantics of applications. The ACG is stored
efficiently in a multilog structure that eliminates contention and is optimised
for locality. Telex supports multiple applications and multi-document updates.
The Telex system clearly separates system logic (which includes replication,
views, undo, security, consistency, conflicts, and commitment) from application
logic. An example application is a shared calendar for managing multi-user
meetings; the system detects meeting conflicts and resolves them consistently
Persistent left superior vena cava mistaken for nodal metastasis: a case report
<p>Abstract</p> <p>Introduction</p> <p>Evaluation of the mediastinum is crucial for patients with lung cancer. Mediastinal lymph node metastases play a dramatic role in the process of staging. Physicians should be aware of the potential pitfalls regarding mediastinal evaluation. This case report provides an example.</p> <p>Case presentation</p> <p>We report the case of a 57-year-old Caucasian man who presented with a four-month history of non-productive cough. He was diagnosed with non-small cell lung cancer. Initially, it was thought to be inoperable due to the presence of a para-aortic lymph node. A more careful examination of the mediastinum revealed that the "lymph node" was in fact a persistent left superior vena cava.</p> <p>Conclusions</p> <p>This study highlights the difficulties in mediastinal staging, especially when intravenous contrast is not used. The recognition of this vascular malformation dramatically changed the therapeutic decisions, giving our patient the opportunity of surgical resection. To the best of our knowledge, such correlation has not been described in English literature.</p
Telex: A Semantic Platform for Cooperative Application Development
International audienceDeveloping write-sharing applications is challenging. Remote and offline data sharing are increasingly important. We propose a generic platform called Telex to ease development and to provide guarantees. Telex is driven by application semantics. Telex takes care of replication and persistence, drives application progress, and ensures that replicas eventually agree on a correct, common state. We show by example how application design proceeds from high-level application invariants to application-provided parameters that guides Telex. The main data structure of Telex is a large, replicated, highly dynamic graph; we discuss the engineering trade-offs for such a graph and our solutions. Finally, we report an experimental evaluation of Telex based on a cooperative calendar application and on benchmarks
Removal of phosphate from aqueous solutions by adsorption onto Ca(OH)2 treated natural clinoptilolite
Phosphorus (P) recovery from wastewater is of great interest especially when the loaded adsorbent can be used in the agriculture as slow-release fertilizer. The application depends on environmental concerns related to the chemical modification of the adsorbent and the release of toxic compounds from the loaded material to the soil or the water during adsorption. The present work focused on the phosphate (PO4-P) removal from aqueous solutions under low P concentrations (0.5ā10mg/L) by using Ca(OH)2-pretreated natural zeolite (CaT-Z). As activation agent, Ca(OH)2 presents benefits in terms of pretreatment costs and environmental impact of the applied adsorbent. The pretreatment of natural zeolite (clinoptilolite) with 0.25mol/L Ca(OH)2 led to an increase of P removal from 1.7 to 97.6% at initial P concentration of 10mg/L, pH 7 and 298K. Low residual concentrations of 81ā238Ī¼g P/L were achieved at 298K rendering CaT-Z a promising sorbent for tertiary wastewater treatment. At 200mg P/L, the adsorption capacity was 7.57mg P/g CaT-Z. The P removal efficiency was pH-independent suggesting a beneficial use of CaT-Z under acidic and alkaline conditions. Adsorption was found to be an endothermic and slow process reaching equilibrium after 120h, whereas the half of the PO4-P was adsorbed in the first 8h. The applied kinetic models showed that both film and intraparticle diffusion contributed to phosphate removal. Phosphate sorption decreased in the presence of the anionic surfactant SDS, Fe2+, HCO3ā, acetate and citrate anion. The predominant mechanisms of ligand exchange and Ca-P surface precipitation were confirmed by the IR-ATR and SEM-EDS analyses, respectively
Chemical Wave Computing from Labware to Electrical Systems
Unconventional and, specifically, wave computing has been repeatedly studied in laboratory based experiments by utilizing chemical systems like a thin film of BelousovāZhabotinsky (BZ) reactions. Nonetheless, the principles demonstrated by this chemical computer were mimicked by mathematical models to enhance the understanding of these systems and enable a more detailedinvestigation of their capacity. As expected, the computerized counterparts of the laboratory based experiments are faster and less expensive. A further step of acceleration in wave-based computingis the development of electrical circuits that imitate the dynamics of chemical computers. A key component of the electrical circuits is the memristor which facilitates the non-linear behavior of the chemical systems. As part of this concept, the road-map of the inspiration from wave-based computing on chemical media towards the implementation of equivalent systems on oscillating memristive circuits was studied here. For illustration reasons, the most straightforward example was demonstrated, namely the approximation of Boolean gates
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