1,121 research outputs found
Focus feature percolation: Evidence from Tundra Nenets and Tundra Yukaghir
Two Siberian languages, Tundra Nenets and Tundra Yukaghir, do not obey strong island constraints in questioning: any sub-constituent of a relative or adverbial clause can be questioned. We argue that this has to do with how focusing works in these languages. The focused sub-constituent remains in situ, but there is abundant morphosyntactic evidence that the focus feature is passed up to the head of the clause. The result is the formation of a complex focus structure in which both the head and non head daughter are overtly marked as focus, and they are interpreted as a pairwise list such that the focus background is applicable to this list, but not to other alternative list
Charge transfer mechanism and Tc(x) dependence in Y0.8(Ca)0.2Ba2Cu3O6+x
We propose a model for charge transfer mechanism in Y0.8(Ca)0.2Ba2Cu3O6+x to
count hole doping of CuO2 planes and x dependence of critical transition
temperature T_c. It is assumed the total number of doped holes in the planes is
sum of holes that are introduced through two separate channels: substitution of
Y3+ by Ca2+ and from CuO chains that are longer than a minimal (critical)
length l_min needed for charge transfer to take place. The T_c(x) dependence is
obtained by combining calculated x dependence of doping, p(x), and universal
T_c versus p relation. Although calculated T_c(x) dependences for l_min=3 and
l_min=4 both remarkably correlate to the experimental T_c(x), we argue that the
value l_min=4 gives a reasonable overall agreement.Comment: Four pages of text, 2 figures, corrected typing error in abstract:
Y2+ and Ca3+ replaced by Y3+ and Ca2+. Thw word "each" added in page 3, line
4. Accepted in Superconductor Science and Technology, on 07.Apr.2008, after
having been considerably revise
The microRNA analysis portal is a next-generation tool for exploring and analyzing miRNA-focused data in the literature.
MicroRNAs constitute a class of noncoding small RNAs involved in the posttranscriptional regulation of many biological pathways. In recent years, microRNAs have also been associated with regulation across kingdoms, demonstrating that exogenous miRNAs can function in mammals in a fashion similar to mammalian miRNAs. The growing interest in microRNAs and the increasing amount of literature and molecular and biomedical data available make it difficult to identify records of interest and keep up to date with novel findings. For these reasons, we developed the microRNA Analysis Portal (MAP). MAP selects relevant miRNA-focused articles from PubMed, links biomedical and molecular data and applies bioinformatics modules. At the time of this writing, MAP represents the richest, most complete and integrated database focused on microRNAs. MAP also integrates an updated version of MirCompare (2.0), a computational platform used for selecting plant microRNAs on the basis of their ability to regulate mammalian genes. Both MAP and MirCompare functionalities were used to predict that microRNAs from Moringa oleifera have putative roles across kingdoms by regulating human genes coding for proteins of the immune system. Starting from a selection of 94 human microRNAs, MirCompare selected 6 Moringa oleifera functional homologs. The subsequent prediction of human targets and areas of functional enrichment highlighted the central involvement of these genes in regulating immune system processes, particularly the host-virus interaction processes in hepatitis B, cytomegalovirus, papillomavirus and coronavirus. This case of use showed how MAP can help to perform complex queries without any computational background. MAP is available at http://stablab.uniroma2.it/MAP
A role for TSPO in mitochondrial Ca2+ homeostasis and redox stress signaling
The 18 kDa translocator protein TSPO localizes on the outer mitochondrial membrane (OMM). Systematically overexpressed at sites of neuroinflammation it is adopted as a biomarker of brain conditions. TSPO inhibits the autophagic removal of mitochondria by limiting PARK2-mediated mitochondrial ubiquitination via a peri-organelle accumulation of reactive oxygen species (ROS). Here we describe that TSPO deregulates mitochondrial Ca2+ signaling leading to a parallel increase in the cytosolic Ca2+ pools that activate the Ca2+-dependent NADPH oxidase (NOX) thereby increasing ROS. The inhibition of mitochondrial Ca2+ uptake by TSPO is a consequence of the phosphorylation of the voltage-dependent anion channel (VDAC1) by the protein kinase A (PKA), which is recruited to the mitochondria, in complex with the Acyl-CoA binding domain containing 3 (ACBD3). Notably, the neurotransmitter glutamate, which contributes neuronal toxicity in age-dependent conditions, triggers this TSPO-dependent mechanism of cell signaling leading to cellular demise. TSPO is therefore proposed as a novel OMM-based pathway to control intracellular Ca2+ dynamics and redox transients in neuronal cytotoxicity
Aligning daily activities with personality: towards a recommender system for improving wellbeing
Recommender Systems have not been explored to a great extentfor improving health and subjective wellbeing. Recent advances inmobile technologies and user modelling present the opportunityfor delivering such systems, however the key issue is understand-ing the drivers of subjective wellbeing at an individual level. Inthis paper we propose a novel approach for deriving personalizedactivity recommendations to improve subjective wellbeing by maxi-mizing the congruence between activities and personality traits. Toevaluate the model, we leveraged a rich dataset collected in a smart-phone study, which contains three weeks of daily activity probes,the Big-Five personality questionnaire and subjective wellbeingsurveys. We show that the model correctly infers a range of activ-ities that are ’good’ or ’bad’ (i.e. that are positively or negativelyrelated to subjective wellbeing) for a given user and that the derivedrecommendations greatly match outcomes in the real-world
A Sublinear Variance Bound for Solutions of a Random Hamilton Jacobi Equation
We estimate the variance of the value function for a random optimal control
problem. The value function is the solution of a Hamilton-Jacobi
equation with random Hamiltonian
in dimension . It is known that homogenization occurs as , but little is known about the statistical fluctuations of .
Our main result shows that the variance of the solution is bounded
by . The proof relies on a modified Poincar\'e
inequality of Talagrand
Positive temperature versions of two theorems on first-passage percolation
The estimates on the fluctuations of first-passsage percolation due to
Talagrand (a tail bound) and Benjamini--Kalai--Schramm (a sublinear variance
bound) are transcribed into the positive-temperature setting of random
Schroedinger operators.Comment: 15 pp; to appear in GAFA Seminar Note
Identification of <i>Salvia haenkei</i> as gerosuppressant agent by using an integrated senescence-screening assay.
Cellular senescence is a stable cell cycle arrest that is the causative process of aging. The PI3K/AKT/mTOR pathway is implicated in the control of cellular senescence and inhibitors of this pathway have been successfully used for life span prolongation experiments in mammals. PTEN is the major regulator of the PI3K/AKT/mTOR pathway and loss of PTEN promotes a senescence response termed PICS. Here we report a novel-screening assay, for the identification of compounds that block different types of senescence response. By testing a library of more than 3000 natural and chemical compounds in PTEN deficient cells we have found that an extract from <i>Salvia haenkei</i> (SH), a native plant of Bolivia is a potent inhibitor of PICS. SH also decreases replicative and UV-mediated senescence in human primary fibroblasts and in a model of <i>in vitro</i> reconstructed human epidermis. Mechanistically, SH treatment affects senescence driven by UV by interfering with IL1-α signalling. Pre-clinical and clinical testing of this extract by performing toxicity and irritability evaluation <i>in vitro</i> also demonstrate the safety of SH extract for clinical use as anti-aging skin treatment
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