4,943 research outputs found
Functions of innovation systems as a framework to understand sustainable technological change: empirical evidence for earlier claims
Understanding the emergence of innovation systems is recently put central in research analysing the process of technological change. Especially the key-activities that are important for the build up of an innovation system receive much attention. These are labeled ‘functions of innovation systems’. In most cases the authors apply this framework without questioning its validity. This paper builds on five empirical studies, related to renewable energy technologies, to test whether the functions of innovation systems framework is a valid framework to analyse processes of technological change. We test the claim that a specific set of functions is suitable. We also test whether the claim made in previous publications that the interactions between system functions accelerate innovation system emergence and growth is valid. Both claims are confirmed.
Surface plasmon resonance imaging for affinity-based biosensors
SPR imaging (SPRi) is at the forefront of optical label-free and real-time detection. It offers the possibility of monitoring hundreds of biological interactions simultaneously and from the binding profiles, allows the estimation of the kinetic parameters of the interactions between the immobilised probes and the ligands in solution. We review the current state of development of SPRi technology and its application including commercially available SPRi instruments. Attention is also given to surface chemistries for biochip functionalisation and suitable approaches to improve sensitivity
Organic supply chain collaboration: a case study in eight EU Countries
This study aims at contributing to a better understanding of the linkage between supply chain performance and possible performance improvement with respect to food quality and safety. Therefore, the paper addresses the question whether the level of collaborative planning and close supply chain relationships could help improve quality and safety of organic supply chains. The study was conducted as a part of the multi-disciplinary EU-wide survey of organic supply chains, carried out in 8 European countries. In this paper we report the results of the study regarding the structures and performance of six different organic supply chains in these eight European countries: milk (CH, UK), apples (DE, CH), pork (UK, NL), eggs (DE, UK), wheat (HU, IT, FR) and tomatoes (IT, NL). In depth interviews with key-informants were carried out in 2006 to investigate the structures, performance and relationships within the supply chains. Results show a low level of collaboration among various actors especially on cost and benefits sharing. Highly integrated supply chains show higher collaboration especially in the domain of Decision Synchronization. Trust and collaboration appear to be related with increased performance, while, the higher the perceived risk for quality and safety is, the higher the probability of supply chain collaboration.Agricultural and Food Policy, Food Consumption/Nutrition/Food Safety,
DNMT3B in vitro knocking-down is able to reverse embryonal rhabdomyosarcoma cell phenotype through inhibition of proliferation and induction of myogenic differentiation
Aberrant DNA methylation has been frequently observed in many human cancers, including rhabdomyosarcoma (RMS), the most common soft tissue sarcoma in children. To date, the expression and function of the de novo DNA methyltransferase (DNMT) 3B in RMS have not yet been investigated. Our study show for the first time a significant up-regulation of DNMT3B levels in 14 RMS tumour samples and 4 RMS cell lines in comparison to normal skeletal muscle. Transfection of RD and TE671 cells, two in vitro models of embryonal RMS (ERMS), with a synthetic DNMT3B siRNA decreased cell proliferation by arresting cell cycle at G1 phase, as demonstrated by the reduced expression of Cyclin B1, Cyclin D1 and Cyclin E2, and by the concomitant up-regulation of the checkpoint regulators p21 and p27. DNMT3B depletion also impaired RB phosphorylation status and decreased migratory capacity and clonogenic potential. Interestingly, DNMT3B knock-down was able to commit ERMS cells towards myogenic terminal differentiation, as confirmed by the acquisition of a myogenic-like phenotype and by the increased expression of the myogenic markers MYOD1, Myogenin and MyHC. Finally, inhibition of MEK/ERK signalling by U0126 resulted in a reduction of DNMT3B protein, giving evidence that DNMT3B is a down-stream molecule of this oncogenic pathway.Taken together, our data indicate that altered expression of DNMT3B plays a key role in ERMS development since its silencing is able to reverse cell cancer phenotype by rescuing myogenic program. Epigenetic therapy, by targeting the DNA methylation machinery, may represent a novel therapeutic strategy against RMS
Crizotinib-induced antitumour activity in human alveolar rhabdomyosarcoma cells is not solely dependent on ALK and MET inhibition
BACKGROUND: Rhabdomyosarcoma (RMS) is the most commonly diagnosed malignant soft tissue tumour in children and adolescents. Aberrant expression of Anaplastic Lymphoma Kinase (ALK) and MET gene has been implicated in the malignant progression of RMS, especially in the alveolar subtype. This observation suggests that crizotinib (PF-02341066), a kinase inhibitor against ALK and MET, may have a therapeutic role in RMS, although its antitumour activity in this malignancy has not yet been studied.
METHODS: RH4 and RH30 alveolar RMS (ARMS) cell lines were treated with crizotinib and then assessed by using proliferation, viability, migration and colony formation assays. Multiple approaches, including flow cytometry, immunofluorescence, western blotting and siRNA-based knock-down, were used in order to investigate possible molecular mechanisms linked to crizotinib activity.
RESULTS: In vitro treatment with crizotinib inhibited ALK and MET proteins, as well as Insulin-like Growth Factor 1 Receptor (IGF1R), with a concomitant robust dephosphorylation of AKT and ERK, two downstream kinases involved in RMS cell proliferation and survival. Exposure to crizotinib impaired cell growth, and accumulation at G2/M phase was attributed to an altered expression and activation of checkpoint regulators, such as Cyclin B1 and Cdc2. Crizotinib was able to induce apoptosis and autophagy in a dose-dependent manner, as shown by caspase-3 activation/PARP proteolytic cleavage down-regulation and by LC3 activation/p62 down-regulation, respectively. The accumulation of reactive oxygen species (ROS) seemed to contribute to crizotinib effects in RH4 and RH30 cells. Moreover, crizotinib-treated RH4 and RH30 cells exhibited a decreased migratory/invasive capacity and clonogenic potential.
CONCLUSIONS: These results provide a further insight into the molecular mechanisms affected by crizotinib in ARMS cells inferring that it could be a useful therapeutic tool in ARMS cancer treatment
Spectroscopy of an AdS Reissner-Nordstrom black hole
In the framework of black hole spectroscopy, we extend the results obtained
for a charged black hole in an asymptotically flat spacetime to the scenario
with non vanishing negative cosmological constant. In particular, exploiting
Hamiltonian techniques, we construct the area spectrum for an AdS
Reissner-Nordstrom black hole.Comment: 21 pages, enhanced conclusions, references adde
SMAUG: a new technique for the deprojection of galaxy clusters
This paper presents a new technique for reconstructing the spatial
distributions of hydrogen, temperature and metal abundance of a galaxy cluster.
These quantities are worked out from the X-ray spectrum, modeled starting from
few analytical functions describing their spatial distributions. These
functions depend upon some parameters, determined by fitting the model to the
observed spectrum. We have implemented this technique as a new model in the
XSPEC software analysis package. We describe the details of the method, and
apply it to work out the structure of the cluster A1795. We combine the
observation of three satellites, exploiting the high spatial resolution of
Chandra for the cluster core, the wide collecting area of XMM-Newton for the
intermediate regions and the large field of view of Beppo-SAX for the outer
regions. We also test the validity and precision of our method by i) comparing
its results with those from a geometrical deprojection, ii) examining the
spectral residuals at different radii of the cluster and iii) reprojecting the
unfolded profiles and comparing them directly to the measured quantities. Our
analytical method yields the parameters defining the spatial functions directly
from the spectra. Their explicit knowledge allows a straightforward derivation
of other indirect physical quantities like the gravitating mass, as well as a
fast and easy estimate of the profiles uncertainties.Comment: 24 pages, 11 figures, 3 tables; emulateapj; accepted for publication
in the Astrophysical Journa
Social situational business ethics framing for engaging with ethics issues
This article considers the problem of how employees and observers of business ethics behaviors often do not know how to safely and effectively engage with business ethics issues and cases. The ameliorative method of social situational business ethics framing was analyzed. Key parts of the related literature from philosophy, sociology, organizational studies, and business ethics are reviewed. A literature gap between general framing theory and business ethics was identified with respect to the need for social situational framing in business ethics at the micro individual, meso organizational, and macro institutional levels. Theoretical propositions for bridging the literature gap and a wide variety of business ethics engagement case examples are developed as illustrations of and support for the propositions. Practical social situational business ethics framing implications for safe and effective business ethics engagement are considered.</p
Amorphous silica modeled with truncated and screened Coulomb interactions: A molecular dynamics simulation study
We show that finite-range alternatives to the standard long-range BKS pair
potential for silica might be used in molecular dynamics simulations. We study
two such models that can be efficiently simulated since no Ewald summation is
required. We first consider the Wolf method, where the Coulomb interactions are
truncated at a cutoff distance r_c such that the requirement of charge
neutrality holds. Various static and dynamic quantities are computed and
compared to results from simulations using Ewald summations. We find very good
agreement for r_c ~ 10 Angstroms. For lower values of r_c, the long--range
structure is affected which is accompanied by a slight acceleration of dynamic
properties. In a second approach, the Coulomb interaction is replaced by an
effective Yukawa interaction with two new parameters determined by a force
fitting procedure. The same trend as for the Wolf method is seen. However,
slightly larger cutoffs have to be used in order to obtain the same accuracy
with respect to static and dynamic quantities as for the Wolf method.Comment: 10 pages; 11 fig
The Complete Local Volume Groups Sample - I. Sample Selection and X-ray Properties of the High-Richness Subsample
We present the Complete Local-Volume Groups Sample (CLoGS), a statistically
complete optically-selected sample of 53 groups within 80 Mpc. Our goal is to
combine X-ray, radio and optical data to investigate the relationship between
member galaxies, their active nuclei, and the hot intra-group medium (IGM). We
describe sample selection, define a 26-group high-richness subsample of groups
containing at least 4 optically bright (log L_B>=10.2 LBsol) galaxies, and
report the results of XMM-Newton and Chandra observations of these systems. We
find that 14 of the 26 groups are X-ray bright, possessing a group-scale IGM
extending at least 65kpc and with luminosity >10^41 erg/s, while a further 3
groups host smaller galaxy-scale gas halos. The X-ray bright groups have masses
in the range M_500=0.5-5x10^13 Msol, based on system temperatures of 0.4-1.4
keV, and X-ray luminosities in the range 2-200x10^41 erg/s. We find that
~53-65% of the X-ray bright groups have cool cores, a somewhat lower fraction
than found by previous archival surveys. Approximately 30% of the X-ray bright
groups show evidence of recent dynamical interactions (mergers or sloshing),
and ~35% of their dominant early-type galaxies host AGN with radio jets. We
find no groups with unusually high central entropies, as predicted by some
simulations, and confirm that CLoGS is in principle capable of detecting such
systems. We identify three previously unrecognized groups, and find that they
are either faint (L_X,R500<10^42 erg/s) with no concentrated cool core, or
highly disturbed. This leads us to suggest that ~20% of X-ray bright groups in
the local universe may still be unidentified.Comment: Accepted for publication by MNRAS, 25 Manuscript pages with 6 tables
and 10 figures, plus 30 pages of appendices. v2 corrects minor typographical
errors identified at proof stag
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