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Characteristics and influence of biosmoke on the fine-particle ionic composition measured in Asian outflow during the Transport and Chemical Evolution Over the Pacific (TRACE-P) experiment
Probing the Position Resolved Energy Density Inside Photonic Scattering Slabs with Strong Absorption and Anisotropy
Understanding the transport of light in photonic scattering media is crucial for many application areas, such as atmospheric and climate sciences [1,2], oceanography [3], biophysics [4,5], powder technology [6], and solid-state lighting [7,8]. In photonic scattering media, such as paint, foam, and tissue, the refractive index varies spatially causing incident waves to be scattered and absorbed [9,10]. While Monte Carlo simulations accurately describe light transport in complex media, they are extremely slow and require high computation power. Fast and accurate analytical methods are needed especially for industrial applications. The P1 approximation to the radiative transfer equation (RTE) is a commonly utilized analytical method [11]. However, it is known that P1 fails for samples with both predominant forward scattering and strong absorption, resulting in unphysical negative energy densities. The accuracy of the analytical PN approximation depends on the order N, the scattering properties of the sample, like albedo, anisotropy, optical thickness, and refractive index contrast of the sample and the surrounding medium [12].</p
Self-Organization and the Physics of Glassy Networks
Network glasses are the physical prototype for many self-organized systems,
ranging from proteins to computer science. Conventional theories of gases,
liquids, and crystals do not account for the strongly material-selective
character of the glass-forming tendency, the phase diagrams of glasses, or
their optimizable properties. A new topological theory, only 25 years old, has
succeeded where conventional theories have failed. It shows that (probably all
slowly quenched) glasses, including network glasses, are the result of the
combined effects of a few simple mechanisms. These glass-forming mechanisms are
topological in nature, and have already been identified for several important
glasses, including chalcogenide alloys, silicates (window glass, computer
chips), and proteins.Comment: One PDF file contains 10 figures and tex
Theorems on existence and global dynamics for the Einstein equations
This article is a guide to theorems on existence and global dynamics of
solutions of the Einstein equations. It draws attention to open questions in
the field. The local-in-time Cauchy problem, which is relatively well
understood, is surveyed. Global results for solutions with various types of
symmetry are discussed. A selection of results from Newtonian theory and
special relativity that offer useful comparisons is presented. Treatments of
global results in the case of small data and results on constructing spacetimes
with prescribed singularity structure or late-time asymptotics are given. A
conjectural picture of the asymptotic behaviour of general cosmological
solutions of the Einstein equations is built up. Some miscellaneous topics
connected with the main theme are collected in a separate section.Comment: Submitted to Living Reviews in Relativity, major update of Living
Rev. Rel. 5 (2002)
Reaction rates and transport in neutron stars
Understanding signals from neutron stars requires knowledge about the
transport inside the star. We review the transport properties and the
underlying reaction rates of dense hadronic and quark matter in the crust and
the core of neutron stars and point out open problems and future directions.Comment: 74 pages; commissioned for the book "Physics and Astrophysics of
Neutron Stars", NewCompStar COST Action MP1304; version 3: minor changes,
references updated, overview graphic added in the introduction, improvements
in Sec IV.A.
‘How, for God’s sake, can I be a good Muslim?' Gambian Youth in Search of a Moral Lifestyle
By analysing the case study of a young Muslim man's conversion within and between different expressions of Islam in the Gambia, this article challenges common understandings of conversion that see it as a transition from one form of religious belief or identity to another, as well as theories of Islam's place in Africa that distinguish between ‘local’ traditions and ‘world’ religions. The ethnographic case study illustrates that, for Gambian youth, conversion is not a unilinear path but entails the continuous making of moral negotiations and a preparedness to reflect on the ambiguity of selfhood – an inevitable result of the making of these negotiations
Development of a biomechanical energy harvester
© 2009 Li et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
HER2 gene amplification and EGFR expression in a large cohort of surgically staged patients with nonendometrioid (type II) endometrial cancer
Type II endometrial cancers (uterine serous papillary and clear cell histologies) represent rare but highly aggressive variants of endometrial cancer (EC). HER2 and EGFR may be differentially expressed in type II EC. Here, we evaluate the clinical role of HER2 and EGFR in a large cohort of surgically staged patients with type II (nonendometrioid) EC and compare the findings with those seen in a representative cohort of type I (endometrioid) EC. In this study HER2 gene amplification was studied by fluorescence in situ hybridisation (FISH) and EGFR expression by immunohistochemistry. Tissue microarrays were constructed from 279 patients with EC (145 patients with type I and 134 patients with type II EC). All patients were completely surgically staged and long-term clinical follow up was available for 258 patients. The rate of HER2 gene amplification was significantly higher in type II EC compared with type I EC (17 vs 1%, P<0.001). HER2 gene amplification was detected in 17 and 16% of the cases with uterine serous papillary and clear cell type histology, respectively. In contrast, EGFR expression was significantly lower in type II compared with type I EC (34 vs 46%, P=0.041). EGFR expression but not HER2 gene amplification was significantly associated with poor overall survival in patients with type II EC, (EGFR, median survival 20 vs 33 months, P=0.028; HER2, median survival 18 vs 29 months, P=0.113) and EGFR expression retained prognostic independence when adjusting for histology, stage, grade, and age (EGFR, P=0.0197; HER2, P=0.7855). We conclude that assessment of HER2 gene amplification and/or EGFR expression may help to select type II EC patients who could benefit from therapeutic strategies targeting both HER2 and EGFR
Mechanisms of hypoxic up-regulation of versican gene expression in macrophages
Hypoxia is a hallmark of many pathological tissues. Macrophages accumulate in hypoxic sites and up-regulate a range of hypoxia-inducible genes. The matrix proteoglycan versican has been identified as one such gene, but the mechanisms responsible for hypoxic induction are not fully characterised. Here we investigate the up-regulation of versican by hypoxia in primary human monocyte-derived macrophages (HMDM), and, intriguingly, show that versican mRNA is up-regulated much more highly (>600 fold) by long term hypoxia (5 days) than by 1 day of hypoxia (48 fold). We report that versican mRNA decay rates are not affected by hypoxia, demonstrating that hypoxic induction of versican mRNA is mediated by increased transcription. Deletion analysis of the promoter identified two regions required for high level promoter activity of luciferase reporter constructs in human macrophages. The hypoxia-inducible transcription factor HIF-1 has previously been implicated as a key potential regulator of versican expression in hypoxia, however our data suggest that HIF-1 up-regulation is unlikely to be principally responsible for the high levels of induction observed in HMDM. Treatment of HMDM with two distinct specific inhibitors of Phosphoinositide 3-kinase (PI3K), LY290042 and wortmannin, significantly reduced induction of versican mRNA by hypoxia and provides evidence of a role for PI3K in hypoxic up-regulation of versican expression
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