292 research outputs found
Structure in the optical absorption edge of amorphous selenium technical note no. 8
Temperature measurement of absorption spectrum near band edge of amorphous selenium on evaporated samples with and without substrate
Research in far ultraviolet filtering for space optical systems
Design and fabrication of multilayer interference filters for ultraviole
Hedgehog-mediated regulation of PPARγ controls metabolic patterns in neural precursors and shh-driven medulloblastoma
Sonic hedgehog (Shh) signaling is critical during development and its aberration is common across the spectrum of human malignancies. In the cerebellum, excessive activity of the Shh signaling pathway is associated with the devastating pediatric brain tumor medulloblastoma. We previously demonstrated that exaggerated de novo lipid synthesis is a hallmark of Shh-driven medulloblastoma and that hedgehog signaling inactivates the Rb/E2F tumor suppressor complex to promote lipogenesis. Indeed, such Shh-mediated metabolic reprogramming fuels tumor progression, in an E2F1- and FASN-dependent manner. Here, we show that the nutrient sensor PPARγ is a key component of the Shh metabolic network, particularly its regulation of glycolysis. Our data show that in primary cerebellar granule neural precursors (CGNPs), proposed medulloblastoma cells-of-origin, Shh stimulation elicits a marked induction of PPARγ alongside major glycolytic markers. This is also documented in the actively proliferating Shh-responsive CGNPs in the developing cerebellum, and PPARγ expression is strikingly elevated in Shh-driven medulloblastoma in vivo. Importantly, pharmacological blockade of PPARγ and/or Rb inactivation inhibits CGNP proliferation, drives medulloblastoma cell death and extends survival of medulloblastoma-bearing animals in vivo. This coupling of mitogenic Shh signaling to a major nutrient sensor and metabolic transcriptional regulator define a novel mechanism through which Shh signaling engages the nutrient sensing machinery in brain cancer, controls the cell cycle, and regulates the glycolytic index. This also reveals a dominant role of Shh in the etiology of glucose metabolism in medulloblastoma and underscores the function of the Shh → E2F1 → PPARγ axis in altering substrate utilization patterns in brain cancers in favor of tumor growth. These findings emphasize the value of PPARγ downstream of Shh as a global therapeutic target in hedgehog-dependent and/or Rb-inactivated tumors
Are sciences essential and humanities elective? Disentangling competing claims for humanities research public value
[EN] Recent policy discourse suggests that arts and humanities research is seen as being less useful to society than other disciplines, notably in science, technology, engineering and mathematics. The paper explores how this assumption s construction has been built and whether it is based upon an unfair prejudice: we argue for a prima facie case to answer in assuming that arts and humanities research s lower societal value. We identify a set of claims circulating in policy circles regarding science, technology, engineering and math- ematics research and arts and humanities research s differences. We find two groups: arts and humanities research is less useful than science, technology, engineering and mathematics, and arts and humanities research is merely differently useful. We argue that empirical analysis is necessary to disentangle which ones are true to assess whether policy-making is being based on rational and evidence-based claims. We argue that debates about public research value should recognise that humanities have different (but equally valid) kinds of societal value.This work was supported by the Spanish Ministry of Education, which funded the PhD research fellowship of Julia Olmos Peñuela through the F.P.U program [AP2007- 01850]. The research fellowship took place in the framework of the HERAVALUE project, Measuring the public value of arts and humanities research, financially supported by the HERA Joint Research Programme, cofunded by AHRC, AKA, DASTI, ETF, FNR, FWF, HAZU, IRCHSS, MHEST, NWO, RANNIS, RCN, VR and The European Community FP7 2007-2013, under the Socio-economic Sciences and Humanities programme. The
authors would like to thank the editors and two anonymous referees for their invaluable comments. Any errors or omissions remain the authors’ responsibilitieOlmos-Peñuela, J.; Benneworth, P.; Castro-Martínez, E. (2015). Are sciences essential and humanities elective? Disentangling competing claims for humanities research public value. Arts and Humanities in Higher Education. 14(1):61-78. https://doi.org/10.1177/1474022214534081S617814
Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC
The uncertainty on the calorimeter energy response to jets of particles is
derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the
calorimeter response to single isolated charged hadrons is measured and
compared to the Monte Carlo simulation using proton-proton collisions at
centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009
and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter
response to specific types of particles (positively and negatively charged
pions, protons, and anti-protons) is measured and compared to the Monte Carlo
predictions. Finally, the jet energy scale uncertainty is determined by
propagating the response uncertainty for single charged and neutral particles
to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3%
for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table,
submitted to European Physical Journal