34,001 research outputs found
Divine Deception in Descartes’ Meditations
Descartes, Divine deception, First Meditation, Suare
Search for Pair Production of Scalar Leptoquarks
This article describes the search for pair production of scalar leptoquarks
performed by the CMS collaboration using the data from the 2010 proton-proton
run of the Large Hadron Collider at a center of mass energy of 7 TeV. The
following final state signatures from the decay of a pair of scalar leptoquarks
are described in here: the di-lepton plus jets final state (where the leptons
are either both electrons or both muons) and the lepton plus jets and
transverse missing energy final state (where the lepton is an electron).Comment: 8 pages, 10 figures, 3 tables, presented at the DPF conference
(August 9-13, 2011
Graphene oxide nanoribbons induce autophagic vacuoles in neuroblastoma cell lines
Since graphene nanoparticles are attracting increasing interest in relation to medical applications, it is important to understand their potential effects on humans. In the present study, we prepared graphene oxide (GO) nanoribbons by oxidative unzipping of single-wall carbon nanotubes (SWCNTs) and analyzed their toxicity in two human neuroblastoma cell lines. Neuroblastoma is the most common solid neoplasia in children. The hallmark of these tumors is the high number of different clinical variables, ranging from highly metastatic, rapid progression and resistance to therapy to spontaneous regression or change into benign ganglioneuromas. Patients with neuroblastoma are grouped into different risk groups that are characterized by different prognosis and different clinical behavior. Relapse and mortality in high risk patients is very high in spite of new advances in chemotherapy. Cell lines, obtained from neuroblastomas have different genotypic and phenotypic features. The cell lines SK-N-BE(2) and SH-SY5Y have different genetic mutations and tumorigenicity. Cells were exposed to low doses of GO for different times in order to investigate whether GO was a good vehicle for biological molecules delivering individualized therapy. Cytotoxicity in both cell lines was studied by measuring cellular oxidative stress (ROS), mitochondria membrane potential, expression of lysosomial proteins and cell growth. GO uptake and cytoplasmic distribution of particles were studied by Transmission Electron Microscopy (TEM) for up to 72 h. The results show that GO at low concentrations increased ROS production and induced autophagy in both neuroblastoma cell lines within a few hours of exposure, events that, however, are not followed by growth arrest or death. For this reason, we suggest that the GO nanoparticle can be used for therapeutic delivery to the brain tissue with minimal effects on healthy cells
Architecture, colour and images. Ideas and designs by Friedensreich Hundertwasser
Colour, imagination, inspiration, amazement. These four words very fittingly describe the work of the Viennese artist/architect Friedrich Stowasser, better known as Hundertwasser (meaning hundred water), a master of organic thinking who between 1928 and 2000 worked and lived in Vienna, Venice and New Zealand. He uses eye-catching images to convey his ideas, forcefully expressive chromatic forms and patterns that betray a strong link with a re-interpreted geometric structure. This contribution, inspired by Hundertwasser’s works, intends to study the unique relationship between creativity, imagination and architecture based on sociological, cultural and psychological principles
Decision Rules and their Influence on Asset Prices
This paper develops a market microstructure model with asymmetric information in order to quantify the influence which practical decision rules have on asset process. The users of practical decision rules have incomplete information at their disposal and trade in a market with both fully informed and uninformed investors, as well as with a competitive market maker. The users of practical decision rules affect the periodical ask and bid prices in two ways: by means of the precision of their information and through their share in the totality of investors, respectively. The resulting bid-ask spread is positive and proportional to the c.p. variation of these two influencing factors and is attributable to the adverse selection costs.
Tuning the order of colloidal monolayers: assembly of heterogeneously charged colloids close to a patterned substrate
We study the behavior of negatively charged colloids with two positively
charged polar caps close to a planar patterned surface. The competition between
the different anisotropic components of the particle-particle interaction
patterns is able by itself to give rise to a rich assembly scenario: colloids
with charged surface patterns form different crystalline domains when adsorbed
to a homogeneously charged substrate. Here we consider substrates composed of
alternating (negative/neutral, positive/neutral and positive/negative) parallel
stripes and, by means of Monte Carlo simulations, we investigate the ordering
of the colloids on changing the number of the stripes. We show that the
additional competition between the two different lengths scales characterizing
the system ( the particle interaction range and the size of the stripes)
gives rise to a plethora of distinct particle arrangements, where some
well-defined trends can be observed. By accurately tuning the substrate charged
motif it is possible to, promote specific particles arrangements,
disfavor crystalline domains or induce the formation of extended, open
clusters.Comment: 18 pages, 15 figure
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