1,176 research outputs found
Fermi Velocity Spectrum and Incipient Magnetism in TiBe2
We address the origin of the incipient magnetism in TiBe through precise
first principles calculations, which overestimate the ferromagnetic tendency
and therefore require correction to account for spin fluctuations. TiBe has
sharp fine structure in its electronic density of states, with a van Hove
singularity only 3 meV above the Fermi level. Similarly to the isovalent weak
ferromagnet ZrZn, it is flat bands along the K-W-U lines of hexagonal face
of the fcc Brillouin zone make the system prone to magnetism, and more so if
electrons are added. We find that the Moriya coefficient (multiplying
in the fluctuation susceptibility )
is divergent when the velocity vanishes at a point on the Fermi surface, which
is very close (3 meV) to occurring in TiBe. In exploring how the FM
instability (the =0 Stoner enhancement is ) might be suppressed
by fluctuations in TiBe, we calculate that the Moriya A coefficient (of
) is negative, so =0 is not the primary instability. Explicit
calculation of shows that its maximum occurs at the X point
; TiBe is thus an incipient {\it anti}ferromagnet
rather than ferromagnet as has been supposed. We further show that simple
temperature smearing of the peak accounts for most of the temperature
dependence of the susceptibility, which previously had been attributed to local
moments (via a Curie-Weiss fit), and that energy dependence of the density of
states also strongly affects the magnetic field variation of
4-[3,5-Bis(2-hydroxyphenyl)-1H-1,2,4-triazol-1-yl]benzoic acid dimethylformamide monosolvate
In the molecule of deferasirox dimethylformamide solvate, C21H15N3O4·C3H7NO, the central 1,2,4-triazole ring is tilted with respect to the benzoic acid and one of the 2-hydroxyphenyl units but coplanar with the other 2-hydroxyphenyl group, as indicated by the dihedral angles of 33.69 (9), 72.57 (8) and 5.18 (9)°, respectively. Intramolecular O—H⋯N hydrogen bonds generate an S(6) ring motif. In the crystal, deferasirox molecules are linked by O—H⋯N hydrogen bonds and weak C—H⋯O interactions into chains along the c axis. The dimethylformamide solvent molecules are located between the deferasirox chains and are linked to the deferasirox molecules by O—H⋯O hydrogen bonds and weak C—H⋯O interactions
Dystrophin glycoprotein complex dysfunction:a regulatory link between muscular dystrophy and cancer cachexia
SummaryCachexia contributes to nearly a third of all cancer deaths, yet the mechanisms underlying skeletal muscle wasting in this syndrome remain poorly defined. We report that tumor-induced alterations in the muscular dystrophy-associated dystrophin glycoprotein complex (DGC) represent a key early event in cachexia. Muscles from tumor-bearing mice exhibited membrane abnormalities accompanied by reduced levels of dystrophin and increased glycosylation on DGC proteins. Wasting was accentuated in tumor mdx mice lacking a DGC but spared in dystrophin transgenic mice that blocked induction of muscle E3 ubiquitin ligases. Furthermore, DGC deregulation correlated positively with cachexia in patients with gastrointestinal cancers. Based on these results, we propose that, similar to muscular dystrophy, DGC dysfunction plays a critical role in cancer-induced wasting
Future changes in tropical cyclone activity in the North Indian Ocean projected by high-resolution MRI-AGCMs
Open Access at publisher's web site: http://www.springerlink.com/content/b682734237171631
Designing BODIPY-based probes for fluorescence imaging of β-amyloid plaques
Styryl-congutated BODIPY dyes which are structurally similar to known Aβ peptide binding dyes, were designed and synthesized. The binding is accompanied by a large increase in the emission intensity in all cases, suggesting a high potential for use in the fluorescence imaging of Aβ plaques. © 2014 the Partner Organisations
Electrodeposition of CuGaSe2 and CuGaS2 thin films for photovoltaic applications
The final publication is available at Springer via http://dx.doi.org/10.1007/s10008-016-3237-0.Abstract CuGaSe2 and CuGaS2 polycrystalline thin film absorbers were prepared by one-step electrodeposition from an
aqueous electrolyte containing CuCl2, GaCl3 and H2SeO3.
The pH of the solution was adjusted to 2.3 by adding HCl
and KOH. Annealing improved crystallinity of CuGaSe2 and
further annealing in sulphur atmosphere was required to obtain CuGaS2 layers. The morphology, topography, chemical
composition and crystal structure of the deposited thin films
were analysed by scanning electron microscopy, atomic force
microscopy, energy dispersive spectroscopy and X-ray diffraction, respectively. X-Ray diffraction showed that the asdeposited CuGaSe2 film exhibited poor crystallinity, but
which improved dramatically when the layers were annealed
in forming gas atmosphere for 40 min. Subsequent
sulphurization of CuGaSe2 films was performed at 400 °C
for 10 min in presence of molecular sulphur and under
forming gas atmosphere. The effect of sulphurization was
the conversion of CuGaSe2 into CuGaS2. The formation of
CuGaS2 thin films was evidenced by the shift observed in the
X-ray diffraction pattern and by the blue shift of the optical
bandgap. The bandgap of CuGaSe2 was found to be 1.66 eV,
while for CuGaS2 it raised up to 2.2 eV. A broad intermediate
absorption band associated to Cr and centred at 1.63 eV was
observed in Cr-doped CuGaS2 films.This work was supported by Ministerio de Economia y Competitividad (ENE2013-46624-C4-4-R) and Generalitat Valenciana (Prometeus 2014/044). One of the authors (S. Ullah) acknowledges the European Union (IDEAS-Call-3, Innovation and Design for Euro-Asian scholars) for its financial support.Ullah, S.; Mollar García, MA.; Marí, B. (2016). Electrodeposition of CuGaSe2 and CuGaS2 thin films for photovoltaic applications. Journal of Solid State Electrochemistry. 20(8):2251-2257. https://doi.org/10.1007/s10008-016-3237-0S22512257208Calixto ME, Sebastian PJ, Bhattacharya RN, Noufi (1999) Sol Energ Mat Sol C 59:75–84Mandati S, Sarada BV, Dey SR, Joshi SV (2015) J Power Sources 273:149–157Jacobsson TJ, Fjällström V, Edoff M, Edvinsson T (2015) Sol Energ Mat Sol C 134:185–193Carrete A, Placidi M, Shavel A, Pérez Rodríguez A, Cabot A (2015) Phys Stat Sol (a) 212:67–71Saji VS, Ik-Ho C, Lee CW (2011) Sol Energy 86:2666–2678Park MG, Ahn SJ, Yun JH, Gwak J, Cho A, Ahn SK, Shin K, Nam D, Cheong H, Yoon K (2012) J Alloy Compd 513:68–74Saji VS, Lee SM, Lee CW (2011) J Korean Electrochem Soc 14:61–70Donglin X, Jangzhuang L, Man X, Xiujian Z (2008) J Non-Cryst Solids 354:1447–1450Araujo J, Ortíz R, López-Rivera A, Ortega JM, Montilla M, Alarcón D (2007) J Solid State Electroch 11(Issue 3):407–412Palacios P, Sanchez K, Conesa JC, Fernandez JJ, Wahnon P (2007) Phys Stat Sol A 203:1395–1401Palacios P, Sanchez K, Conesa JC, Wahnon P (2006) Thin Solid Films 515:6280–6284Lee H, Lee J-H, Hwang Y-H, Kim Y (2014) Curr Appl Phys 14:18–22Kim D, Kwon Y, Lee D, Yoon S, Lee S, Yoo B (2015) J Electrochem Soc 162:D36–D41Hou WW, Bob B, Li S, Yang Y (2009) Thin Solid Films 517:6853–6856Lee J, Lee W, Shrestha NK, Lee DY, Lim I, Kang SH, Nah YC, Lee SH, Yi W, Han SH (2014) Mater Chem Phys 144:49–54Yang JY, Lee D, Huh K, Jung SJ, Lee JW, Lee HC, Baek DH, Kim BJ, Kim D, Nam J, Kim GY, Jo W (2015) RSC Adv 5:40719–407257Sall T, Nafidi A, Marí B, Mollar M, Hartiti B, Fahoume M (2014) J Semicond 35:0630021–0630025Lee JH, Song WC, Yi JS, Joonyang K, Han WD, Hawang J (2003) Thin Solid Films 431-432:349–353Prabukanthan P, Dhanasekaran R (2007) Cryst Growth Des 7:618–623Guillemoles JF, Cowache P, Lusson A, Fezzaa K, Boisivon F, Vedel J, Lincot D (1996) J Appl Phys 79:7293–7302Aguilera I, Palacios P, Wahon P (2010) Sol Energ Mat Sol C 94:1903–1906Palacios P, Aguilera I, Wahnón P, Conesa JC (2008) J Phys Chem C 112:9525–952
CCL2 recruits inflammatory monocytes to facilitate breast-tumour metastasis
Macrophages abundantly found in the tumor microenvironment enhance malignancy(1). At metastatic sites a distinct population of metastasis associated macrophages (MAMs) promote tumor cell extravasation, seeding and persistent growth(2). Our study has defined the origin of these macrophages by showing Gr1+ inflammatory monocytes (IMs) are preferentially recruited to pulmonary metastases but not primary mammary tumors, a process also found for human IMs in pulmonary metastases of human breast cancer cells. The recruitment of these CCR2 (receptor for chemokine CCL2) expressing IMs and subsequently MAMs and their interaction with metastasizing tumor cells is dependent on tumor and stromal synthesized CCL2 (FigS1). Inhibition of CCL2/CCR2 signaling using anti-CCL2 antibodies blocks IM recruitment and inhibits metastasis in vivo and prolongs the survival of tumor-bearing mice. Depletion of tumor cell-derived CCL2 also inhibits metastatic seeding. IMs promote tumor cell extravasation in a process that requires monocyte-derived VEGF. CCL2 expression and macrophage infiltration are correlated with poor prognosis and metastatic disease in human breast cancer (Fig S2)(3-6). Our data provides the mechanistic link between these two clinical associations and indicates new therapeutic targets for treating metastatic breast disease
Reactor Measurement of theta_12; Principles, Accuracies and Physics Potentials
We discuss reactor measurement of \theta_{12} which has a potential of
reaching the ultimate sensitivity which surpasses all the methods so far
proposed. The key is to place a detector at an appropriate baseline distance
from the reactor neutrino source to have an oscillation maximum at around a
peak energy of the event spectrum in the absence of oscillation. By a detailed
statistical analysis the optimal distance is estimated to be \simeq (50-70) km
x [8 x 10^{-5} eV^2/\Delta m^2_{21}], which is determined by maximizing the
oscillation effect in the event number distribution and minimizing geo-neutrino
background contamination. To estimate possible uncertainty caused by
surrounding nuclear reactors in distance of \sim 100 km, we examine a concrete
example of a detector located at Mt. Komagatake, 54 km away from the
Kashiwazaki-Kariwa nuclear power plant in Japan, the most powerful reactor
complex in the world. The effect turns out to be small. Under a reasonable
assumption of systematic error of 4% in the experiment, we find that
sin^2{\theta_{12}} can be determined to the accuracy of \simeq 2% (\simeq 3%),
at 68.27% CL for 1 degree of freedom, for 60 GW_th kton yr (20 GW_th kton yr)
operation. We also discuss implications of such an accurate measurement of
\theta_{12}.Comment: 31 pages, 8 figures. version to appear in PR
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