47 research outputs found
Intermediate Phases, structural variance and network demixing in chalcogenides: the unusual case of group V sulfides
We review Intermediate Phases (IPs) in chalcogenide glasses and provide a
structural interpretation of these phases. In binary group IV selenides, IPs
reside in the 2.40 < r < 2.54 range, and in binary group V selenides they shift
to a lower r, in the 2.29< r < 2.40 range. Here r represents the mean
coordination number of glasses. In ternary alloys containing equal proportions
of group IV and V selenides, IPs are wider and encompass ranges of respective
binary glasses. These data suggest that the local structural variance
contributing to IP widths largely derives from four isostatic local structures
of varying connectivity r; two include group V based quasi-tetrahedral (r =
2.29) and pyramidal (r = 2.40) units, and the other two are group IV based
corner-sharing (r = 2.40) and edge-sharing (r = 2.67) tetrahedral units.
Remarkably, binary group V (P, As) sulfides exhibit IPs that are shifted to
even a lower r than their selenide counterparts; a result that we trace to
excess Sn chains either partially (As-S) or completely (P-S) demixing from
network backbone, in contrast to excess Sen chains forming part of the backbone
in corresponding selenide glasses. In ternary chalcogenides of Ge with the
group V elements (As, P), IPs of the sulfides are similar to their selenide
counterparts, suggesting that presence of Ge serves to reign in the excess Sn
chain fragments back in the backbone as in their selenide counterparts
Representing Semantified Biological Assays in the Open Research Knowledge Graph
In the biotechnology and biomedical domains, recent text mining efforts
advocate for machine-interpretable, and preferably, semantified, documentation
formats of laboratory processes. This includes wet-lab protocols, (in)organic
materials synthesis reactions, genetic manipulations and procedures for faster
computer-mediated analysis and predictions. Herein, we present our work on the
representation of semantified bioassays in the Open Research Knowledge Graph
(ORKG). In particular, we describe a semantification system work-in-progress to
generate, automatically and quickly, the critical semantified bioassay data
mass needed to foster a consistent user audience to adopt the ORKG for
recording their bioassays and facilitate the organisation of research,
according to FAIR principles.Comment: In Proceedings of 'The 22nd International Conference on Asia-Pacific
Digital Libraries
Neutrino Anomalies in Gauge Mediated Model with Trilinear R violation
The structure of neutrino masses and mixing resulting from trilinear
violating interactions is studied in the presence of the gauge mediated
supersymmetry breaking. Neutrino masses arise in this model at tree level
through the RG-induced vacuum expectation values of the sneutrinos and also
through direct contribution at 1-loop. The relative importance of these
contributions is determined by the values of the strong and weak coupling
constants. In case of purely couplings, the tree contribution
dominates over the 1-loop diagram. In this case, one simultaneously obtains
atmospheric neutrino oscillations and quasi-vacuum oscillations of the solar
neutrinos if all the \l' couplings are assumed to be of similar magnitudes.
If R parity violation arises from the trilinear \l couplings, then the loop
induced contribution dominates over the tree level. One cannot simultaneously
explain the solar and atmospheric deficit in this case if all the \l
couplings are of similar magnitude. This however becomes possible with
hierarchical \l and we give a specific example of this.Comment: 26 pages Latex, 2 figures, certain sections rewritten, improved
discussion about derivations added. To appear in Physical Review
The Discovery Potential of a Super B Factory
The Proceedings of the 2003 SLAC Workshops on flavor physics with a high
luminosity asymmetric e+e- collider. The sensitivity of flavor physics to
physics beyond the Standard Model is addressed in detail, in the context of the
improvement of experimental measurements and theoretical calculations.Comment: 476 pages. Printed copies may be obtained by request to
[email protected] . arXiv admin note: v2 appears to be identical to v
The Thermally Reversing Window in Ternary GexPxS1-2x glasses
GexPxS1-2x glasses in the compositional range 0.05 < x < 0.19 have been
synthesized and examined in temperature modulated differential scanning
calorimetry (MDSC) and Raman scattering experiments. Trends in the
non-reversing enthalpy DHnr(x) near Tg show the term to almost vanish in the
0.090(5) < x < 0.135(5) range, and to increase by an order of magnitude at x <
0.09, and at x > 0.135. In analogy to previous results on chalcogenide glasses,
we identify compositions at x < 0.09 to be elastically floppy, those in the
0.090 0.135
to be stressed rigid. MDSC results also show the DHnr term ages in the
stressed-rigid and floppy phases but not in the intermediate phase. The
intermediate phase is viewed to be a self-organized phase of a disordered
network. It consists of at least four isostatically rigid local structures;
corner-sharing GeS4, edge-sharing GeS2, pyramidal P(S1/2)3 and
quasi-tetrahedral S=P(S1/2)3 units for which evidence comes from Raman
scattering. The latter method also shows existence of P4S7 and P4S10 molecules
in the glasses segregated from the backbone. These aspects of structure
contribute to an intermediate phase that is significantly narrower in width
than in corresponding selenide glasses.Comment: 1 PDF file has text, 9 figures and 3 table
Status of Supersymmetric Seesaw in SO(10) models
We report on the status of supersymmetric seesaw models in the light of
recent experimental results on , and the
light Higgs mass at the LHC. SO(10)-like relations are assumed for neutrino
Dirac Yukawa couplings and two cases of mixing, one large, PMNS-like, and
another small, CKM-like, are considered. It is shown that for the large mixing
case, only a small range of parameter space with moderate is still
allowed. This remaining region can be ruled out by an order of magnitude
improvement in the current limit on BR(). We also explore a
model with non-universal Higgs mass boundary conditions at the high scale. It
is shown that the renormalization group induced flavor violating slepton mass
terms are highly sensitive to the Higgs boundary conditions. Depending on the
choice of the parameters, they can either lead to strong enhancements or
cancellations within the flavor violating terms. Such cancellations might relax
the severe constraints imposed by lepton flavor violation compared to mSUGRA.
Nevertheless for a large region of parameter space the predicted rates lie
within the reach of future experiments once the light Higgs mass constraint is
imposed. We also update the potential of the ongoing and future experimental
searches for lepton flavor violation in constraining the supersymmetric
parameter space.Comment: 18 Pages, 7 figure
Incidence of and risk factors for major haemorrhage in patients treated with ibrutinib: An integrated analysis.
Ibrutinib, a Bruton tyrosine kinase inhibitor, is approved for treatment of various B-cell malignancies. In ibrutinib clinical studies, low-grade haemorrhage was common, whereas major haemorrhage (MH) was infrequent. We analysed the incidence of and risk factors for MH from 15 ibrutinib clinical studies (N = 1768), including 4 randomised controlled trials (RCTs). Rates of any-grade bleeding were similar for single-agent ibrutinib and ibrutinib combinations (39% and 40%). Low-grade bleeding was more common in ibrutinib-treated than comparator-treated patients (35% and 15%), and early low-grade bleeding was not associated with MH. The proportion of MH in RCTs was higher with ibrutinib than comparators (4.4% vs. 2.8%), but after adjusting for longer exposure with ibrutinib (median 13 months vs. 6 months), the incidence of MH was similar (3.2 vs. 3.1 per 1000 person-months). MH led to treatment discontinuation in 1% of all ibrutinib-treated patients. Use of anticoagulants and/or antiplatelets (AC/AP) during the study was common (~50% of patients) and had an increased exposure-adjusted relative risk for MH in both the total ibrutinib-treated population (1.9; 95% confidence interval, 1.2-3.0) and RCT comparator-treated patients (2.4; 95% confidence interval, 1.0-5.6), indicating that ibrutinib may not alter the effect of AC/AP on the risk of MH in B-cell malignancies
Displayed correlation between gene expression profiles and submicroscopic alterations in response to cetuximab, gefitinib and EGF in human colon cancer cell lines
Background: EGFR is frequently overexpressed in colon cancer. We characterized HT-29 and
Caco-2, human colon cancer cell lines, untreated and treated with cetuximab or gefitinib alone and
in combination with EGF.
Methods: Cell growth was determined using a variation on the MTT assay. Cell-cycle analysis was
conducted by flow cytometry. Immunohistochemistry was performed to evaluate EGFR expression
and scanning electron microscopy (SEM) evidenced the ultrastructural morphology. Gene
expression profiling was performed using hybridization of the microarray Ocimum Pan Human 40
K array A.
Results: Caco-2 and HT-29 were respectively 66.25 and 59.24 % in G0/G1. They maintained this
level of cell cycle distribution after treatment, suggesting a predominantly differentiated state.
Treatment of Caco-2 with EGF or the two EGFR inhibitors produced a significant reduction in their
viability. SEM clearly showed morphological cellular transformations in the direction of cellular death in both cell lines treated with EGFR inhibitors. HT-29 and Caco-2 displayed an important
reduction of the microvilli (which also lose their erect position in Caco-2), possibly invalidating
microvilli absorption function. HT-29 treated with cetuximab lost their boundary contacts and
showed filipodi; when treated with gefitinib, they showed some vesicles: generally membrane
reshaping is evident. Both cell lines showed a similar behavior in terms of on/off switched genes
upon treatment with cetuximab. The gefitinib global gene expression pattern was different for the
2 cell lines; gefitinib treatment induced more changes, but directly correlated with EGF treatment.
In cetuximab or gefitinib plus EGF treatments there was possible summation of the morphological
effects: cells seemed more weakly affected by the transformation towards apoptosis. The genes
appeared to be less stimulated than for single drug cases.
Conclusion: This is the first study to have systematically investigated the effect of cetuximab or
gefitinib, alone and in combination with EGF, on human colon cancer cell lines. The EGFR inhibitors
have a weaker effect in the presence of EGF that binds EGFR. Cetuximab treatment showed an
expression pattern that inversely correlates with EGF treatment. We found interesting cytomorphological
features closely relating to gene expression profile. Both drugs have an effect on
differentiation towards cellular death