High-Intensity Discharge Lamp and Duffing Oscillator - Similarities and Differences

The processes inside the arc tube of high-intensity discharge lamps are investigated by finite element simulations. The behavior of the gas mixture inside the arc tube is governed by differential equations describing mass, energy and charge conservation as well as the Helmholtz equation for the acoustic pressure and the Navier-Stokes equation for the flow driven by the buoyancy and the acoustic streaming force. The model is highly nonlinear and requires a recursion procedure to account for the impact of acoustic streaming on the temperature and other fields. The investigations reveal the presence of a hysteresis and the corresponding jump phenomenon, quite similar to a Duffing oscillator. The similarities and, in particular, the differences of the nonlinear behavior of the high-intensity discharge lamp to that of a Duffing oscillator are discussed. For large amplitudes the high-intensity discharge lamp exhibits a stiffening effect in contrast to the Duffing oscillator.Comment: 14 pages, 8 figure

Sourcing and automation decisions in financial value chains

Online research maps are websites that present information about certain research activities in a structured manner. Institutions like universities, states, or individual researchers use them as knowledge base to identify and communicate “who knows what” and “where can the respective information be found”. Furthermore, these items are used as a research marketing measure, stressing the importance of this kind of portal. However, research maps differ in their range of functionalities, their respective naming, their target audience and so on. Thus, it is an exhausting task identifying and choosing the right set of functionalities. Our goal is to offer a template for the creation of common practice online research maps. For this purpose, we present a reference model and describe its development process. As preliminary measure, 66 research maps have been carefully analysed with respect to the formerly mentioned aspects. Derived from the results of our analysis, common practice was identified and used as basis for developing a reference model for online research maps. For development purposes, an existing language for describing internet portals was chosen and adapted to suite the requirements of describing research maps. The reference model presented in this article was then evaluated in a multi-methodical procedure

What is it about humanity that we can't give away to intelligent machines? A European perspective

One of the most significant recent technological developments concerns the development and implementation of ‘intelligent machines’ that draw on recent advances in artificial intelligence (AI) and robotics. However, there are growing tensions between human freedoms and machine controls. This article reports the findings of a workshop that investigated the application of the principles of human freedom throughout intelligent machine develop- ment and use. Forty IS researchers from ten different countries discussed four contemporary AI and humanity issues and the most relevant IS domain challenges. This article summarizes their experiences and opinions regarding four AI and humanity themes: Crime & conflict, Jobs, Attention, and Wellbeing. The outcomes of the workshop discussions identify three attributes of humanity that need preservation: a critique of the design and application of AI, and the intelligent machines it can create; human involvement in the loop of intelligent ma- chine decision-making processes; and the ability to interpret and explain intelligent machine decision-making processes. The article provides an agenda for future AI and humanity researchpublishedVersio

Indications for cardiovascular magnetic resonance in children with congenital and acquired heart disease: an expert consensus paper of the Imaging Working Group of the AEPC and the Cardiovascular Magnetic Resonance Section of the EACVI

This article provides expert opinion on the use of cardiovascular magnetic resonance (CMR) in young patients with congenital heart disease (CHD) and in specific clinical situations. As peculiar challenges apply to imaging children, paediatric aspects are repeatedly discussed. The first section of the paper addresses settings and techniques, including the basic sequences used in paediatric CMR, safety, and sedation. In the second section, the indication, application, and clinical relevance of CMR in the most frequent CHD are discussed in detail. In the current era of multimodality imaging, the strengths of CMR are compared with other imaging modalities. At the end of each chapter, a brief summary with expert consensus key points is provided. The recommendations provided are strongly clinically oriented. The paper addresses not only imagers performing CMR, but also clinical cardiologists who want to know which information can be obtained by CMR and how to integrate it in clinical decision-makin

GRADE equity guidelines 3: considering health equity in GRADE guideline development: rating the certainty of synthesized evidence

Objectives: The aim of this paper is to describe a conceptual framework for how to consider health equity in the Grading Recommendations Assessment and Development Evidence (GRADE) guideline development process. Study Design and Setting: Consensus-based guidance developed by the GRADE working group members and other methodologists. Results: We developed consensus-based guidance to help address health equity when rating the certainty of synthesized evidence (i.e., quality of evidence). When health inequity is determined to be a concern by stakeholders, we propose five methods for explicitly assessing health equity: (1) include health equity as an outcome; (2) consider patient-important outcomes relevant to health equity; (3) assess differences in the relative effect size of the treatment; (4) assess differences in baseline risk and the differing impacts on absolute effects; and (5) assess indirectness of evidence to disadvantaged populations and/or settings. Conclusion: The most important priority for research on health inequity and guidelines is to identify and document examples where health equity has been considered explicitly in guidelines. Although there is a weak scientific evidence base for assessing health equity, this should not discourage the explicit consideration of how guidelines and recommendations affect the most vulnerable members of society

Serpentinization in the trench-outer rise region offshore of Nicaragua: constraints from seismic refraction and wide-angle data

Recent seismic evidence suggested that most oceanic plate hydration is associated with trench-outer rise faulting prior to subduction. Hydration at trenches may have a significant impact on the subduction zone water cycle. Previous seismic experiments conducted to the northwest of Nicoya Peninsula, Northern Costa Rica, have shown that the subducting Cocos lithosphere is pervasively altered, which was interpreted to be due to both hydration (serpentinization) and fracturing of the crustal and upper-mantle rocks. New seismic wide-angle reflection and refraction data were collected along two profiles, running parallel to the Middle American trench axis offshore of central Nicaragua, revealing lateral changes of the seismic properties of the subducting lithosphere. Seismic structure along both profiles is characterized by low velocities both in the crust and upper mantle. Velocities in the uppermost mantle are found to be in the range 7.3–7.5 km s−1; thus are 8–10 per cent lower than velocities typical for unaltered peridotites and hence confirm the assumption that serpentinization is a common process at the trench-outer rise area offshore of Nicaragua. In addition, a prominent velocity anomaly occurred within the crust beneath two seamounts. Here, velocity reduction may indicate increased porosity and perhaps permeability, supporting the idea that seamounts serve as sites for water percolation and circulation

Expression and clinical significance of Glucose Regulated Proteins GRP78 (BiP) and GRP94 (GP96) in human adenocarcinomas of the esophagus

<p>Abstract</p> <p>Background</p> <p>Glucose regulated proteins (GRPs) are main regulators of cellular homeostasis due to their role as molecular chaperones. Moreover, the functions of GRPs suggest that they also may play important roles in cancer biology. In this study we investigated the glucose regulated proteins GRP78 (BiP) and GRP94 (GP96) in a series of human esophageal adenocarcinomas to determine their implications in cancer progression and prognosis.</p> <p>Methods</p> <p>Formalin-fixed, paraffin-embedded tissues of primary resected esophageal (Barrett) adenocarcinomas (n = 137) and corresponding normal tissue were investigated. mRNA-gene expression levels of GRP78 and GRP94 were determined by quantitative real-time RT-PCR after mRNA extraction. Protein expression analysis was performed with immunohistochemical staining of the cases, assembled on a tissue micorarray. The results were correlated with pathologic features (pT, pN, G) and overall survival.</p> <p>Results</p> <p>GRP78 and GRP94 mRNA were expressed in all tumors. The relative gene expression of GRP78 was significantly higher in early cancers (pT1m and pT1sm) as compared to more advanced stages (pT2 and pT3) and normal tissue (p = 0.031). Highly differentiated tumors showed also higher GRP78 mRNA levels compared to moderate and low differentiated tumors (p = 0.035). In addition, patients with higher GRP78 levels tended to show a survival benefit (p = 0.07). GRP94 mRNA-levels showed no association to pathological features or clinical outcome.</p> <p>GRP78 and GRP94 protein expression was detectable by immunohistochemistry in all tumors. There was a significant correlation between a strong GRP78 protein expression and early tumor stages (pT1m and pT1sm, p = 0.038). For GRP94 low to moderate protein expression was significantly associated with earlier tumor stage (p = 0.001) and less lymph node involvement (p = 0.036). Interestingly, the patients with combined strong GRP78 and GRP94 protein expression exclusively showed either early (pT1m or pT1sm) or advanced (pT3) tumor stages and no pT2 stage (p = 0.031).</p> <p>Conclusion</p> <p>We could demonstrate an association of GRP78 and GRP94 mRNA and protein expression with tumor stage and behaviour in esophageal adenocarcinomas. Increased expression of GRP78 may be responsible for controlling local tumor growth in early tumor stages, while high expression of GRP78 and GRP94 in advanced stages may be dependent from other factors like cellular stress reactions due to glucose deprivation, hypoxia or the hosts' immune response.</p