1,108 research outputs found
Lepton flavor violating semileptonic decays in a topcolor scenario
The contributions of the neutral top-pion and the non-universal
gauge boson predicted by topcolor scenario to the lepton flavor violating
semileptonic decays
and are discussed. We find that the contributions of
to these decay processes are generally larger than those from .
can only make the value of the branching ratio
in the range of 1 1, which is far below
the sensitivity of foreseeable experiments. With reasonable values of the free
parameters, the non-universal gauge boson can make the value of the
branching ratio reach 1, which
might approach the observable threshold of near-future experiments.Comment: 15 pages. Discussions added, some typos correcte
A Social Media Policy for Clinical Mental Health Counseling Programs
The American Counseling Association 2014 Ethical Code mandates that counselors who engage in social media communication develop knowledge and skills related to ethical and legal considerations (American Counseling Association, 2014). In response to these expectations, this article introduces a social media policy created by faculty in a Clinical Mental Health Counseling program. An example and review of an implemented social media policy is provided, along with guidelines for a student-led training program. Case examples are provided that illustrate potential dilemmas of student misuse of social media, along with examples of faculty interventions. This article is designed to contribute to the professional discourse on how to address social media and technology in counselor training
Uptake and mitochondrial dysfunction of alpha-synuclein in human astrocytes, cortical neurons and fibroblasts
© 2013 Braidy et al.; licensee BioMed Central Ltd.
This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.The accumulation and aggregation of alpha-synuclein (α-syn) in several tissue including the brain is a major
pathological hallmark in Parkinson’s disease (PD). In this study, we show that α-syn can be taken up by primary
human cortical neurons, astrocytes and skin-derived fibroblasts in vitro. Our findings that brain and peripheral cells
exposed to α-syn can lead to impaired mitochondrial function, leading to cellular degeneration and cell death,
provides additional evidence for the involvement of mitochondrial dysfunction as a mechanism of toxicity of α-syn
in human cells
Sulfone-containing covalent organic frameworks for photocatalytic hydrogen evolution from water
Nature uses organic molecules for light harvesting and photosynthesis, but most man-made water splitting catalysts are inorganic semiconductors. Organic photocatalysts, while attractive because of their synthetic tunability, tend to have low quantum efficiencies for water splitting. Here we present a crystalline covalent organic framework (COF) based on a benzo-bis(benzothiophene sulfone) moiety that shows a much higher activity for photochemical hydrogen evolution than its amorphous or semicrystalline counterparts. The COF is stable under long-term visible irradiation and shows steady photochemical hydrogen evolution with a sacrificial electron donor for at least 50 hours. We attribute the high quantum efficiency of fused-sulfone-COF to its crystallinity, its strong visible light absorption, and its wettable, hydrophilic 3.2 nm mesopores. These pores allow the framework to be dye-sensitized, leading to a further 61% enhancement in the hydrogen evolution rate up to 16.3 mmol g −1 h −1 . The COF also retained its photocatalytic activity when cast as a thin film onto a support
Associations of Maternal Dietary Patterns during Pregnancy with Offspring Adiposity from Birth Until 54 Months of Age
10.3390/nu9010002Nutrients91article no. 2GUSTO (Growing up towards Healthy Outcomes
Effects of a portion design plate on food group guideline adherence among hospital staff
Food group guideline adherence is vital to prevent obesity and diabetes. Various studies have demonstrated that environmental variables influence food intake behaviour. In the present study we examined the effect of a portion design plate with food group portion guidelines demarcated by coloured lines (ETE Plate™).
A two-group quasi-experimental design was used to measure proportions of carbohydrate, vegetable and protein portions and user experience in a hospital staff lounge setting in Singapore. Lunch was served on the portion design plate before 12.15 hours. For comparison, a normal plate (without markings) was used after 12.15 hours. Changes in proportions of food groups from 2 months before the introduction of the design plate were analysed in a stratified sample at baseline (859 subjects, all on normal plates) to 1, 3 and 6 months after (in all 1016 subjects on the design plate, 968 subjects on the control plate).
A total of 151 participants were asked about their experiences and opinions. Between-group comparisons were performed using ___t___ tests. Among those served on the portion design plate at 6 months after its introduction, the proportion of vegetables was 4·71 % (P < 0·001) higher and that of carbohydrates 2·83 % (P < 0·001) lower relative to the baseline. No significant change was found for proteins (−1·85 %).
Over 6 months, we observed different change patterns between the different food group proportions. While participants were positive about the portion design plate, they did not think it would influence their personal behaviour. A portion design plate might stimulate food group guideline adherence among hospital staff and beyond
Comparison of s- and d-wave gap symmetry in nonequilibrium superconductivity
Recent application of ultrafast pump/probe optical techniques to
superconductors has renewed interest in nonequilibrium superconductivity and
the predictions that would be available for novel superconductors, such as the
high-Tc cuprates. We have reexamined two of the classical models which have
been used in the past to interpret nonequilibrium experiments with some
success: the mu* model of Owen and Scalapino and the T* model of Parker.
Predictions depend on pairing symmetry. For instance, the gap suppression due
to excess quasiparticle density n in the mu* model, varies as n^{3/2} in d-wave
as opposed to n for s-wave. Finally, we consider these models in the context of
S-I-N tunneling and optical excitation experiments. While we confirm that
recent pump/probe experiments in YBCO, as presently interpreted, are in
conflict with d-wave pairing, we refute the further claim that they agree with
s-wave.Comment: 14 pages, 11 figure
Spawning rings of exceptional points out of Dirac cones
The Dirac cone underlies many unique electronic properties of graphene and
topological insulators, and its band structure--two conical bands touching at a
single point--has also been realized for photons in waveguide arrays, atoms in
optical lattices, and through accidental degeneracy. Deformations of the Dirac
cone often reveal intriguing properties; an example is the quantum Hall effect,
where a constant magnetic field breaks the Dirac cone into isolated Landau
levels. A seemingly unrelated phenomenon is the exceptional point, also known
as the parity-time symmetry breaking point, where two resonances coincide in
both their positions and widths. Exceptional points lead to counter-intuitive
phenomena such as loss-induced transparency, unidirectional transmission or
reflection, and lasers with reversed pump dependence or single-mode operation.
These two fields of research are in fact connected: here we discover the
ability of a Dirac cone to evolve into a ring of exceptional points, which we
call an "exceptional ring." We experimentally demonstrate this concept in a
photonic crystal slab. Angle-resolved reflection measurements of the photonic
crystal slab reveal that the peaks of reflectivity follow the conical band
structure of a Dirac cone from accidental degeneracy, whereas the complex
eigenvalues of the system are deformed into a two-dimensional flat band
enclosed by an exceptional ring. This deformation arises from the dissimilar
radiation rates of dipole and quadrupole resonances, which play a role
analogous to the loss and gain in parity-time symmetric systems. Our results
indicate that the radiation that exists in any open system can fundamentally
alter its physical properties in ways previously expected only in the presence
of material loss and gain
Notch Signaling Functions as a Cell-Fate Switch between the Endothelial and Hematopoietic Lineages
Recent studies have begun to elucidate how the endothelial lineage is specified from the nascent mesoderm. However, the molecular mechanisms which regulate this process remain largely unknown. We hypothesized that Notch signaling might play an important role in specifying endothelial progenitors from the mesoderm, given that this pathway acts as a bipotential cell-fate switch on equipotent progenitor populations in other settings. We found that zebrafish embryos with decreased levels of Notch signaling exhibited a significant increase in the number of endothelial cells, whereas embryos with increased levels of Notch signaling displayed a reduced number of endothelial cells. Interestingly, there is a concomitant gain of endothelial cells and loss of erythrocytes in embryos with decreased Notch activity, without an effect on cell proliferation or apoptosis. Lineage-tracing analyses indicate that the ectopic endothelial cells in embryos with decreased Notch activity originate from mesodermal cells that normally produce erythrocyte progenitors. Taken together, our data suggest that Notch signaling negatively regulates the number of endothelial cells by limiting the number of endothelial progenitors within the mesoderm, probably functioning as a cell-fate switch between the endothelial and the hematopoietic lineages
External validation of The Paddington International Virtual Electronic Chromoendoscopy Score as a good endoscopic score to define mucosal healing and predict long-term clinical outcomes in ulcerative colitis
Aims: To define endoscopic and histological remission in ulcerative colitis accurately, several score systems have been established. A novel Paddington International Virtual ChromoendoScopy ScOre (PICaSSO) virtual electronic chromoendoscopy (VEC) was recently developed, validated, and reproduced to assess inflammation grade and predict prognosis. We externally verified and validated the clinical value of the PICaSSO score in UC patients. Methods: This prospective study enrolled 63 UC patients. The Mayo Endoscopic Score (MES), UC Endoscopic Index of Severity (UCEIS), and PICaSSO score were adopted for endoscopic evaluation. All biopsies were scored using the Robarts Histological Index (RHI), Nancy Histological Index (NHI), and Extent, Chronicity, Activity, and additional findings (ECAP). Patients with an endoscopic MES of 0-1 at baseline were followed up with the median time of 23.5 months. Results: PICaSSO was strongly correlated with other endoscopic and histological scores. PICaSSO ≤3 had advantages in assessing histological remission (HR), with the highest accuracy of 88.9% for ECAP-HR. Relapse-free survival rates were significantly different between patients with MES 0 and MES 1 and patients with PICaSSO ≤3 vs>3 (P = 0.010 and 0.018, respectively). Conclusions: PICaSSO was externally validated with strong correlations with other endoscopic and histopathologic scoring systems in UC, and PICaSSO-ER might potentially predict the better long-term clinical outcomes in UC patients
- …