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Phase of solar activity affects response of solar proxy Be-10

The solar proxy Be-10, measured in natural archives, has previously been assumed to lag solar activity by 1-2 yr. This reflects its residence time in the stratosphere where its main source lies. This study, based on a 30-yr global model simulation of the atmospheric transport of Be-10, shows that the stratospheric fraction of production varies significantly with the phase of solar activity. This l

Sparse approximation of functions using sums of exponentials and AAK theory

We consider the problem of approximating functions by sums of few exponentials functions, either on an interval or on the positive half-axis. We study both continuous and discrete cases, i.e. when the function is replaced by a number of equidistant samples. Recently, an algorithm has been constructed by Beylkin and Monzón for the discrete case. We provide a theoretical framework for understanding

Ikaros and leukaemia.

The IKZF1 gene at 7p12.2 codes for IKAROS (also termed IKZF1), an essential transcription factor in haematopoiesis involved primarily in lymphoid differentiation. Its importance is underlined by the fact that deregulation of IKAROS results in leukaemia in both mice and men. During recent years, constitutional as well as acquired genetic changes of IKZF1 have been associated with human disease. For

Impact of a paternal origin of germline BRCA1/2 mutations on the age at breast and ovarian cancer diagnosis in a Southern Swedish cohort.

Three studies have reported that BRCA1/2 mutations of paternal origin confer an earlier age at breast cancer diagnosis compared with maternal origin. The primary aim of this study was to investigate the impact of parental origin of BRCA1/2 mutations on age at breast and ovarian cancer diagnosis. This study included 577 female BRCA1/2 mutation carriers. All BRCA1/2 mutation carriers belonged to fam

Rapid shifts in Atta cephalotes fungus-garden enzyme activity after a change in fungal substrate (Attini, Formicidae)

Fungus gardens of the basidiomycete Leucocoprinus gongylophorus sustain large colonies of leaf-cutting ants by degrading the plant material collected by the ants. Recent studies have shown that enzyme activity in these gardens is primarily targeted toward starch, proteins and the pectin matrix associated with cell walls, rather than toward structural cell wall components such as cellulose and hemi

Lymph node tissue kallikrein-related peptidase 6 mRNA: a progression marker for colorectal cancer

BACKGROUND: A most important characteristic feature for poor prognosis in colorectal cancer (CRC) is the presence of lymph node metastasis. Determination of carcinoembryonic antigen (CEA) mRNA levels in lymph nodes has proven powerful for quantification of disseminated tumour cells. Here, we investigate the utility of human tissue kallikrein-related peptidase 6 (KLK6) mRNA as a progression biomark

Gain of chromosomal region 20q and loss of 18 discriminates between Lynch syndrome and familial colorectal cancer

Lynch syndrome and familial colorectal cancer type X, FCCTX, represent the two predominant colorectal cancer syndromes. Whereas Lynch syndrome is clinically and genetically well defined, the genetic cause of FCCTX is unknown and genomic differences between Lynch syndrome and FCCTX tumours are largely unknown. We applied array-based comparative genomic hybridisation to 23 colorectal cancers from FC

Iron Age migration on the island of Öland : Apportionment of strontium by means of Bayesian mixing analysis

Migration is a complex subject to approach in archeology and the new materials and methods available, such as isotope analysis and DNA, make it possible, and necessary, to ask new questions. The objective of this paper is to highlight the possibilities with using a new approach to migration on a population level by applying Bayesian mixing analysis of strontium isotopes. The selected case, the isl

Zooming in on the small: The plasticity of striatal dendritic spines in l-DOPA-Induced dyskinesia.

The spiny dendrites of striatal projection neurons integrate synaptic inputs of different origins to regulate movement. It has long been known that these dendrites lose spines and display atrophic features in Parkinson's disease (PD), but the significance of these morphological changes has remained unknown. Some recent studies reveal a remarkable structural plasticity of striatal spines in parkins

Differentiated Knowledge Bases and the Nature of Innovation Networks

It is argued in this paper that the nature of innovation networks can vary substantially with regard to the type of knowledge that is critical for innovation. Subject to the knowledge base of an industry, networks between companies can differ in various aspects, such as their geographical configuration, their structure, the type of actors holding a strategic position and the type of relations betw

Vocational education and training – an engine for growth and a vehicle for social inclusion?

Vocational education and training (VET) has in recent years enjoyed a revival for two major reasons. Firstly, it is regarded as a suitable means of promoting economic growth. Secondly, it is seen as a potentially powerful tool for fostering social inclusion. In this review, these assumed effects are critically examined on the basis of the vastly expanding literature in the field. Evidence of the p

Assessment of oxidative burst in avian whole blood samples: Validation and application of a chemiluminescence method based on Pholasin

Immunoecology deals with the questions about how immune defences have evolved and are being used and optimized in different environments, ecological settings and lineages. In such research, often only single time point measures and small sample volumes are available, which limits the applicability of traditional immunological methods. Methodological progress in the field thus largely depends on th

Review of LCA studies of solid waste management systems - Part I: Lessons learned and perspectives.

The continuously increasing solid waste generation worldwide calls for management strategies that integrate concerns for environmental sustainability. By quantifying environmental impacts of systems, life cycle assessment (LCA) is a tool, which can contribute to answer that call. But how, where and to which extent has it been applied to solid waste management systems (SWMSs) until now, and which l

Segmented tetrasulfonated copoly(arylene ether sulfone)s: improving proton transport properties by extending the ionic sequence

The morphologies and proton-transport efficiencies of segmented copoly(arylene ether sulfone) ionomers that contain tetrasulfonated sequences are compared with the corresponding copolymers with disulfonated sequences. Tetrasulfonated 4,4′-bis[(4-chlorophenyl)sulfonyl]-1,1′-biphenyl (sBCPSBP) is synthesized by metalation and sulfination. This new monomer is then used in K2CO3-mediated polycondensat

A computational micro-sphere model applied to the simulation of phase-transformations

We present an efficient model for the simulation of polycrystalline materials undergoing solid to solid phase transformations. As a basis, we use a one-dimensional, thermodynamically consistent phase-transformation model. This model is embedded into a micro-sphere formulation in order to simulate three-dimensional boundary value problems. To solve the underlying evolution equations, we use a newly