QCD Sum Rules, Scattering Length and the Vector Mesons in Nuclear Medium

Critical examination is made on the relation between the mass shift of vector mesons in nuclear medium and the vector-meson $-$ nucleon scattering length. We give detailed comparison between the QCD sum rule approach by two of the present authors (Phys. Rev. {\bf C46} (1992) R34) and the scattering-length approach by Koike (Phys. Rev. {\bf C51} (1995) 1488). It is shown that the latter approach is mortally flawed both technically and conceptually.Comment: 16 pages, latex, 4 figures appended as uu-encoded fil

In-Plane Deformation Mechanics for Highly Stretchable Electronics

Scissoring in thick bars suppresses buckling behavior in serpentine traces that have thicknesses greater than their widths, as detailed in a systematic set of analytical and experimental studies. Scissoring in thick copper traces enables elastic stretchability as large as approximate to 350%, corresponding to a sixfold improvement over previously reported values for thin geometries (approximate to 60%).</p

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine

[This corrects the article DOI: 10.1186/s13054-016-1208-6.]

Pan-cancer analysis of whole genomes

Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe

Progradation and erosion of a fine-grained tidally dominated delta: A case study of the Jiangsu coast, China

A large proportion of the world population lives in the coastal zone, which is facing a variety of natural and anthropogenic impacts on its evolution. A better understanding of coastal evolution can be obtained when it is based on an accurate knowledge of coastal dynamics. This thesis aims to study the long-term (hundreds of years) coastal evolution of the Jiangsu coast, China, under both natural and anthropogenic impacts. The recent (hundreds of years) evolution of the Jiangsu coast is closely related to the shifting course of the Yellow River. The coastline of Jiangsu experienced a rapid progradation stage (1128~1855), when the Yellow River discharged into the Yellow Sea, and a following modification stage (after 1855), when the Yellow River abandoned its piror course. Simultaneously, the sedimentary environment of the Jiangsu coast changed from sandy to silty. In contrast, the tide, which is a dominant driving force for the sediment transport and morphological changes along the Jiangsu coast, has been stable for at least thousands of years. As one of the fundamental factors controlling the coastal evolution, local hydrodynamics has at the outset drawn our attention. A large tidal wave model containing the Bohai Sea, the Yellow Sea and the East China Sea is established to investigate the near-field hydrodynamic conditions of the Jiangsu coast. For instance, existing knowledge always suggested that the geographical position of the Shandong Peninsula is crucial for the local tidal wave system off the Jiangsu coast. However, this is a hypothesis without any verification. Moreover, the role of the local bathymetry on the formation of the radial tidal current off the Jiangsu coast is debatable. These two factors of influence are assessed based on the tidal wave system (Chapter 2). The results demonstrate that the Shandong Peninsula plays a secondary role, rather than a crucial role on the Jiangsu local tidal wave system. The radial tidal current is independent of the geographic position of Shandong Peninsula and local ridge-channel morphologies. Besides the existence of the special tidal wave system, another characteristic of the Jiangsu coast is the existence of the silt-dominated sedimentary environment. To gain insight into the characteristics of silt-dominant sediment, flume experiments with various wave and current conditions have been conducted with two sediment samples from the field (Chapter 3). A high concentration layer is observed near the bottom together with ripples under wave-only conditions. Moreover, a significant vertical sediment sorting phenomenon has been found near-bottom for both sediment samples. As a widely used instrument for measuring suspended sediment concentration in both field and laboratory conditions, the Optical Backscatter Sensor (OBS), has been introducted, requiring additional caution due to its sensitivity to sediment grain size. As observed in the flume experiments, vertical sorting leads to vertical grain size differences in a water column. Thus, traditional approaches converting OBS signals based on one fixed calibration curve (i.e. against the bottom sediment) may lead to large deviations over silt-sand mixed suspensions. To extend the application of OBS for fine mixed sediment, we take the grain size effect into account and propose a new approach (Chapter 4). The new approach introduces an accompanying sediment sample besides the original bed samples for calibrating the OBS instrument. Besides, a multi-fraction sediment model is developed to predict the vertical distribution of sediment grain sizes. The reliability of this approach has been validated by the flume experiments. Regarding the aforementioned coastal evolution of the Jiangsu coast since 1128, previous studies using a geological approach failed to reach a satisfactory agreement. To investigate the long-term evolution of the Jiangsu coast, a large-scale morphodynamic model is established (Chapter 5, 6). Due to the scarcity of historical data, we have simplified several data, such as the bathymetric data and the hydrodynamic conditions (e.g. river discharge). Historical maps, records and geological measurements have been utilized for determining model settings and validating the model results. We first focus on the formation and the development of the deltaic system (Chapter 5). In spite of the simplifications on model setting, the model shows a good capability to reproduce the development of the AYD. Sensitivity analyses of uncertainties (e.g. sediment discharge, accommodation space) on the performance of long-term morphodynamic model are further conducted. Subsequently, we focus on the modification stage of the AYD, when the Yellow River shifted its course after 1855. In this stage, the fluvial impact on the coastal evolution disappeared, while the impact of wave and human activity rose. Therefore, we take tides, waves and artificial revetments (sea dikes) into account in the model to understand the ongoing coastal behavior (Chapter 6). Based on modelling results, the Yellow River has been proven as one of the sediment sources for the RSRs, and the relevant contribution is neither restricted to the northern RSRs nor to a certain period (even at present). Moreover, the results show that the sea dikes play a significant role on the evolution of the nearshore regions, and that wind waves play a remarkable role on the erosion of offshore shoals. In the perspective of time and hydrodyanmic forces, tide is the most dominant force governing the overall evolution of the Jiangsu coast. This thesis addresses the long-term morphological evolution of the Jiangsu coast through a process-based morphodynamic modelling approach. The corresponding insights and findings improve our understanding on the long-term evolution of the Jiangsu coast.Hydraulic EngineeringCivil Engineering and Geoscience

Whole failure process analysis for jointed rock masses based on coupling method of DDA and FEM

The elastic-plastic mechanical behaviour is a typical characteristic of rock mass. The load action will bring on the local destruction, large deformation, even whole failure of rock mass with the discontinuous mediums (e.g. joint, crack and fault). It is a coupling process of the continuous deformation and the discontinuous deformation. The discontinuous deformation analysis (DDA) and finite element method (FEM) are combined to build the elastic-plastic mechanical model. The rock block is divided into the finite element meshes. FEM is used to solve the displacement field and the stress field inside the block. The contacts between the deformable blocks are simulated DDA method. The parametric variational principle is derived to analyze the elastic-plastic problem with above coupling model. The theoretical calculating formulae are obtained from the variational principle. The governing equations of mechanical model are established. The proposed method coupling DDA and FEM is used to implement the simulation and analysis for the deformation process of jointed rock masses around one underground cavern. It is easy to simulate the whole process from plastic to elastic yielding failure, and to the large deformation under the condition of plastic flow or instability

Behavior of Orthotropic Steel-UHPC Composite Bridge Deck under Cyclic Loading

In recent years, ultra-high performance concrete (UHPC) has been introduced in the design of orthotropic steel decks (OSD) to reduce the risk of fatigue cracking. To investigate the fatigue behaviour and fatigue damage process of the orthotropic steel-UHPC composite bridge deck, a fullscale specimen was designed and tested under cyclic loading. Test results show that the fatigue resistance of orthotropic steel-UHPC composite bridge deck satisfies the requirements of the designed vehicle load up to 2 million cycles with no cracks occurred in this phase. Rib-to-crossbeam weld and U-rib butt-welded connection are the two most vulnerable details to crack in OSD under cyclic loading. The fatigue resistance of U-rib bolted connection was investigated, and it is concluded that it performs better than that of U-rib butt-welded connection. The short-headed studs fractured under excessive cyclic loading and 5 types of the fatigue failure modes are identified. And the UHPC layer above the crossbeam exhibited limited number of cracks with the maximum crack width less than 0.05mm at the end of the cyclic, much beyond the requirements.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Steel & Composite Structure

Analysing the influence of preferential flow on pressure transmission and landslide triggering

Water ManagementCivil Engineering and Geoscience

Effective roughness height in high-concentrated flows

The effective roughness height is an important parameter in coastal sediment transport models. It has been extensively investigated in the past but few research results are related to the high-concentrated flows which often occur in a silty coast. A series of experiments has been carried out in a wave-current flume with silt-sized sediment bed. The mean velocity profiles were measured under different combined wave-current conditions. The effective roughness heights were calculated based on the curve fitting of measured velocity profiles by following the velocity profile model of You (1994). The accuracy of three empirical models, namely, Grant and Madsen (1982), Li and Amos (1998) and You (1996) was examined with the 'measured' effective roughness heights. The results show that all the models are not much accurate for the high-concentrated flows, particularly in the case with a relatively small sediment size. Therefore, cautions should be taken when applying those models in the silty coast, particularly during the extreme events.Coastal Engineerin