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An acidic fibroblast growth factor protein generated by alternate splicing acts like an antagonist.
Polymerase chain reaction amplification of cDNA for acidic fibroblast growth factor in several lines of cultured human cells revealed two forms of mRNA. The novel smaller mRNA lacks the entire second coding exon of the acidic fibroblast growth factor gene, whereas the previously identified mRNA consists of three coding exons. The truncated variant of acidic fibroblast growth factor (aFGF') is only 60 amino acids long with an apparent molecular mass of 6.7 kD on sodium dodecyl sulfate gels in contrast to 18 kD for the full-length acidic fibroblast growth factor. aFGF' elicits only minimal fibroblast proliferation and antagonizes the effects of acidic fibroblast growth factor when added exogenously to or when coexpressed with aFGF in BALB/c/3T3 fibroblasts. Thus, the truncated variant of acidic fibroblast growth factor may provide fibroblasts with a unique mechanism for endogenous regulation of their responses to acidic fibroblast growth factor
Nonconventional Large Deviations Theorems
We obtain large deviations theorems for nonconventional sums with underlying
process being a Markov process satisfying the Doeblin condition or a dynamical
system such as subshift of finite type or hyperbolic or expanding
transformation
Expression of prostate-specific antigen (PSA) correlates with poor response to tamoxifen therapy in recurrent breast cancer
Prostate-specific antigen (PSA) is a serine protease which may play a role in a variety of cancer types, including breast cancer. In the present study, we evaluated whether the level of PSA in breast tumour cytosol could be associated with prognosis in primary breast cancer, or with response to tamoxifen therapy in recurrent disease. PSA levels were determined by enzyme-linked immunosorbent assay (ELISA) in breast tumour cytosols, and were correlated with prognosis in 1516 patients with primary breast cancer and with response to first-line tamoxifen therapy in 434 patients with recurrent disease. Relating the levels of PSA with classical prognostic factors, low levels were more often found in larger tumours, tumours of older and post-menopausal patients, and in steroid hormone receptor-negative tumours. There was no significant association between the levels of PSA with grade of differentiation or the number of involved lymph nodes. In patients with primary breast cancer, PSA was not significantly related to the rate of relapse, and a positive association of PSA with an improved survival could be attributed to its relationship to age. In patients with recurrent breast cancer, a high level of PSA was significantly related to a poor response to tamoxifen therapy, and a short progression-free and overall survival after start of treatment for recurrent disease. In Cox multivariate analyses for response to therapy and for (progression-free) survival, corrected for age/menopausal status, disease-free interval, site of relapse and steroid hormone receptor status, PSA was an independent variable of poor prognosis. It is concluded that the level of PSA in cytosols of primary breast tumours might be a marker to select breast cancer patients who may benefit from systemic tamoxifen therapy. © 1999 Cancer Research Campaig
Investigation of fiber/matrix adhesion: test speed and specimen shape effects in the cylinder test
The cylinder test, developed from the microdroplet test, was adapted to assess the interfacial adhesion strength between fiber and matrix. The sensitivity of cylinder test to pull-out speed and specimen geometry was measured. It was established that the effect of test speed can be described as a superposition of two opposite, simultaneous effects which have been modeled mathematically by fitting two parameter Weibull curves on the measured datas. Effects of the cylinder size and its geometrical relation on the measured strength values have been analyzed by finite element method. It was concluded that the geometry has a direct influence on the stress formation. Based on the results achieved, recommendations were given on how to perform the novel single fiber cylinder test
A personalized and context-aware news offer for mobile devices
For classical domains, such as movies, recommender systems have proven their usefulness. But recommending news is more challenging due to the short life span of news content and the demand for up-to-date recommendations. This paper presents a news recommendation service with a content-based algorithm that uses features of a search engine for content processing and indexing, and a collaborative filtering algorithm for serendipity. The extension towards a context-aware algorithm is made to assess the information value of context in a mobile environment through a user study. Analyzing interaction behavior and feedback of users on three recommendation approaches shows that interaction with the content is crucial input for user modeling. Context-aware recommendations using time and device type as context data outperform traditional recommendations with an accuracy gain dependent on the contextual situation. These findings demonstrate that the user experience of news services can be improved by a personalized context-aware news offer
Room temperature plasmon laser by total internal reflection
Plasmon lasers create and sustain intense and coherent optical fields below
light's diffraction limit with the unique ability to drastically enhance
light-matter interactions bringing fundamentally new capabilities to
bio-sensing, data storage, photolithography and optical communications.
However, these important applications require room temperature operation, which
remains a major hurdle. Here, we report a room temperature semiconductor
plasmon laser with both strong cavity feedback and optical confinement to
1/20th of the wavelength. The strong feedback arises from total internal
reflection of surface plasmons, while the confinement enhances the spontaneous
emission rate by up to 20 times.Comment: 8 Page, 2 Figure
Geometric phase outside a Schwarzschild black hole and the Hawking effect
We study the Hawking effect in terms of the geometric phase acquired by a
two-level atom as a result of coupling to vacuum fluctuations outside a
Schwarzschild black hole in a gedanken experiment. We treat the atom in
interaction with a bath of fluctuating quantized massless scalar fields as an
open quantum system, whose dynamics is governed by a master equation obtained
by tracing over the field degrees of freedom. The nonunitary effects of this
system are examined by analyzing the geometric phase for the Boulware, Unruh
and Hartle-Hawking vacua respectively. We find, for all the three cases, that
the geometric phase of the atom turns out to be affected by the space-time
curvature which backscatters the vacuum field modes. In both the Unruh and
Hartle-Hawking vacua, the geometric phase exhibits similar behaviors as if
there were thermal radiation at the Hawking temperature from the black hole.
So, a measurement of the change of the geometric phase as opposed to that in a
flat space-time can in principle reveal the existence of the Hawking radiation.Comment: 14 pages, no figures, a typo in the References corrected, version to
appear in JHEP. arXiv admin note: text overlap with arXiv:1109.033
Contractions of Low-Dimensional Lie Algebras
Theoretical background of continuous contractions of finite-dimensional Lie
algebras is rigorously formulated and developed. In particular, known necessary
criteria of contractions are collected and new criteria are proposed. A number
of requisite invariant and semi-invariant quantities are calculated for wide
classes of Lie algebras including all low-dimensional Lie algebras.
An algorithm that allows one to handle one-parametric contractions is
presented and applied to low-dimensional Lie algebras. As a result, all
one-parametric continuous contractions for the both complex and real Lie
algebras of dimensions not greater than four are constructed with intensive
usage of necessary criteria of contractions and with studying correspondence
between real and complex cases.
Levels and co-levels of low-dimensional Lie algebras are discussed in detail.
Properties of multi-parametric and repeated contractions are also investigated.Comment: 47 pages, 4 figures, revised versio
Radiative Electroweak Symmetry Breaking in a Little Higgs Model
We present a new Little Higgs model, motivated by the deconstruction of a
five-dimensional gauge-Higgs model. The approximate global symmetry is
, breaking to , with a gauged subgroup of
, breaking to . Radiative corrections produce an additional small vacuum misalignment,
breaking the electroweak symmetry down to . Novel features of this
model are: the only un-eaten pseudo-Goldstone boson in the effective theory is
the Higgs boson; the model contains a custodial symmetry, which ensures that
at tree-level; and the potential for the Higgs boson is generated
entirely through one-loop radiative corrections. A small negative mass-squared
in the Higgs potential is obtained by a cancellation between the contribution
of two heavy partners of the top quark, which is readily achieved over much of
the parameter space. We can then obtain both a vacuum expectation value of
GeV and a light Higgs boson mass, which is strongly correlated with the
masses of the two heavy top quark partners. For a scale of the global symmetry
breaking of TeV and using a single cutoff for the fermion loops, the
Higgs boson mass satisfies 120 GeV GeV over much of
the range of parameter space. For raised to 10 TeV, these values increase
by about 40 GeV. Effects at the ultraviolet cutoff scale may also raise the
predicted values of the Higgs boson mass, but the model still favors
GeV.Comment: 32 pages, 10 figures, JHEP style. Version accepted for publication in
JHEP. Includes additional discussion of sensitivity to UV effects and
fine-tuning, revised Fig. 9, added appendix and additional references
Analytic Representation of Finite Quantum Systems
A transform between functions in R and functions in Zd is used to define the
analogue of number and coherent states in the context of finite d-dimensional
quantum systems. The coherent states are used to define an analytic
representation in terms of theta functions. All states are represented by
entire functions with growth of order 2, which have exactly d zeros in each
cell. The analytic function of a state is constructed from its zeros. Results
about the completeness of finite sets of coherent states within a cell are
derived
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