4,663 research outputs found
The Axion and the Goldstone Higgs
We consider the renormalizable -model, in which the
Higgs particle has a pseudo-Nambu-Goldstone boson character, and explore what
the minimal field extension required to implement the Peccei-Quinn symmetry
(PQ) is, within the partial compositeness scenario. It turns out that the
minimal model does not require the enlargement of the exotic fermionic sector,
but only the addition of a singlet scalar: it is sufficient that the exotic
fermions involved in partial compositeness and the singlet scalar become
charged under Peccei-Quinn transformations. We explore the phenomenological
predictions for photonic signals in axion searches for all models discussed.
Because of the constraints imposed on the exotic fermion sector by the Standard
Model fermion masses, the expected range of allowed axion-photon couplings
turns out to be generically narrowed with respect to that of standard invisible
axion models, impacting the experimental quest.Comment: 31 pages, 2 Figures. Description improved, results unchange
Cancer Stem Cells and Signaling Pathways in Colorectal Cancer
Colorectal cancer (CRC) is the third most common cancer in males, the second in females and is the second leading cause of cancer related death worldwide. Despite recent advances in chemotherapy, and targeted therapy for CRC, the prognosis for patients with advanced cancer has remained poor, due to drug resistance, metastasis and recurrence. A small fraction of cells possess tumor propagation abilities. These are termed “cancer stem cells (CSCs). A subset of colorectal cancer stem cells, may hold a key to controlling cancer. The cancer stem cell (CSC) model suggests that tumors are hierarchically organized, only CSCs possess cancer-promoting potential. The killing of CSCs is thought to be a critical component of effective antitumor therapies. A number of signaling pathways, most notably the Wingless related (Wnt), transforming growth factor-beta (TGF-β), Notch and Hedgehog signaling and other mechanisms have been found to be associated with CSCs in CRC. They play important roles in maintaining the growth and functional integrity of CSC. Many new molecules are now being studied to block theses pathways. Some of the molecules block the self-renewal and induction of apoptosis in CSCs. The design of CSC-targeted interventions is a rational target, and reduce local recurrence and metastasis. This review aims to summarize the issue on CSCs and signaling pathway relevant for CRC, which may lead to more effective therapeutic strategies for CRC
Molecular Diagnostics in Colorectal Cancer
Colorectal cancer (CRC) presents in one of three patterns: sporadic colorectal cancer in those without a family history (65-85%); those with a family history (familial CRC) 10-25% of cases; inherited CRC accounting for less of 10% cases and presents as well-characterized cancer predisposition syndromes including Lynch syndrome (hereditary non-polyposis colorectal cancer/HNPCC) which comprises about 1-5% of all colorectal cancer, and multiple polyps CRC, which includes familial adenomatous polyposis (FAP,1%), rare CRC syndrome < 0.1 %). Many efforts have been made to discover the genetic and molecular features of CRC, and there is more evidence that these features determine the prognosis and response to treatment. Colorectal cancer (CRC) is a heterogeneous disease, with three known major molecular groups. The most common is the chromosomal instability group, characterized by an accumulation of mutations in specific oncogens and tumor suppressor genes. The second is the microsatellite instability group, caused by the dysfunction of deoxyribonucleic acid (DNA) mismatch repair genes leading to genetic hypermutability. The CpG island methylation phenotype (CIMP) is the third group, distinguished by hypermethylation. In this review we would like to provide an up-to-date overview of molecular genetic aspects of CRC that are currently important and should guide clinical practice in colorectal cancer in the diagnosis and selection of therapy
FSSG Scale System in Comparison with GERD Questionnaires in Predicting Endoscopic Findings with Reflux Esophagitis
Background:Gastroesophageal reflux diseases(GERD) frequently manifests in varied symptoms other than its classics (heartburn and regurgitation), this variation might hinder its diagnostic effort. Several questionnaires based on symptoms filled by the patients themselves may help in diagnosing GERD without previous endoscopic examination. This study objects to compare endoscopic findings in patients which previously asked to fill the questionnaires (frequency scale for the symptoms of GERD (FSSG)) and GERD questionnaire (GerdQ) in pursuit of reliable and valid instrument to detect GERD before endoscopic approaches. Methods: This study was conducted in cross-sectional design involving 72 patients in Adam Malik Hospital, Medan with symptomps of upper abdominal pain or discomfort with or without heartburn/regurgitation. Subjects were asked to fill both FSSG and GerdQ and underwent endoscopy. Diagnoses made were classified as reflux esophagitis, functional dyspepsia, or other diagnoses. Subsequently we conduct a comparison analysis of both questionnaires' specificity and accuracy using receiver operator curve (ROC) by analyzing the area below the curve. Results: According to endoscopic findings from 72 subjects, we ascertained the following results: 52.8% gastritis, antral ulcer, and esophageal hiatal hernia, 37.5% functional dyspepsia, and reflux esophagitis in 9.7% cases. GerdQ is concluded to be superior in terms of specificity and accuracy compared with FSSG with the following percentages in terms of sensitivity, specificity, accuracy, and p value, respectively: 100%, 23.1%, 61.5%, 0.318 vs. 100%, 73.8%, 86.9%, 0.001. Conclusion: GerdQ is superior compared to FSSG in diagnosing GERD based on clinical symptoms in daily practice
Cultivating diversity and food quality. Proceedings of Diversifood EU Forum, Brussels, 11 April 2018
To tackle this issue, Diversifood team organised a forum with policy makers and stakeholders on the 11th of April 2018, in Brussels.
Diversifood’s aim is to share results and key lessons including new approaches for the management of cultivated biodiversity, for plant breeding for sustainable farming systems, and new relationships among actors of food systems.
In the afternoon, there was time for discussion, knowledge sharing, collecting feedback and extending current policies to include cultivating diversity and food quality (for FP9, CAP 2020, The outputs of this workshop will feed Diversifood’s final recommendations.
The forum was kindly hosted by the European Committee of the Regions (Rue Belliard/Belliardstraat 101, 1040 Brussels)
Noncommutative Sp(2,R) Gauge Theories - A Field Theory Approach to Two-Time Physics
Phase-space and its relativistic extension is a natural space for realizing
Sp(2,R) symmetry through canonical transformations. On a Dx2 dimensional
covariant phase-space, we formulate noncommutative field theories, where
Sp(2,R) plays a role as either a global or a gauge symmetry group. In both
cases these field theories have potential applications, including certain
aspects of string theories, M-theory, as well as quantum field theories. If
interpreted as living in lower dimensions, these theories realize Poincare'
symmetry linearly in a way consistent with causality and unitarity. In case
Sp(2,R) is a gauge symmetry, we show that the spacetime signature is determined
dynamically as (D-2,2). The resulting noncommutative Sp(2,R) gauge theory is
proposed as a field theoretical formulation of two-time physics: classical
field dynamics contains all known results of `two-time physics', including the
reduction of physical spacetime from D to (D-2) dimensions, with the associated
`holography' and `duality' properties. In particular, we show that the solution
space of classical noncommutative field equations put all massless scalar,
gauge, gravitational, and higher-spin fields in (D-2) dimensions on
equal-footing, reminiscent of string excitations at zero and infinite tension
limits.Comment: 32 pages, LaTe
Comment on "High Field Studies of Superconducting Fluctuations in High-Tc Cuprates. Evidence for a Small Gap distinct from the Large Pseudogap"
By using high magnetic field data to estimate the background conductivity,
Rullier-Albenque and coworkers have recently published [Phys.Rev.B 84, 014522
(2011)] experimental evidence that the in-plane paraconductivity in cuprates is
almost independent of doping. In this Comment we also show that, in contrast
with their claims, these useful data may be explained at a quantitative level
in terms of the Gaussian-Ginzburg-Landau approach for layered superconductors,
extended by Carballeira and coworkers to high reduced-temperatures by
introducing a total-energy cutoff [Phys.Rev.B 63, 144515 (2001)]. When
combined, these two conclusions further suggest that the paraconductivity in
cuprates is conventional, i.e., associated with fluctuating superconducting
pairs above the mean-field critical temperature.Comment: 9 pages, 1 figur
Coherent matter waves emerging from Mott-insulators
We study the formation of (quasi-)coherent matter waves emerging from a Mott
insulator for strongly interacting bosons on a one-dimensional lattice. It has
been shown previously that a quasi-condensate emerges at momentum k=\pi/2a,
where a is the lattice constant, in the limit of infinitely strong repulsion
(hard-core bosons). Here we show that this phenomenon persists for all values
of the repulsive interaction that lead to a Mott insulator at a commensurate
filling. The non-equilibrium dynamics of hard-core bosons is treated exactly by
means of a Jordan-Wigner transformation, and the generic case is studied using
a time-dependent density matrix renormalization group technique. Different
methods for controlling the emerging matter wave are discussed.Comment: 20 pages, 11 figures. Published versio
Covariant Duality Symmetric Actions
A manifestly Lorentz and diffeomorphism invariant form for the abelian gauge
field action with local duality symmetry of Schwarz and Sen is given. Some of
the underlying symmetries of the covariant action are further considered. The
Noether conserved charge under continuous local duality rotations is found. The
covariant couplings with gravity and the axidilaton field are discussed.Comment: 9 pages, revtex, no figures; (To appear in Physical Review D
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