607 research outputs found
One Loop Renormalizability of Spontaneously Broken Gauge Theory with a Product of Gauge Groups on Noncommutative Spacetime: the U(1) x U(1) Case
A generalization of the standard electroweak model to noncommutative
spacetime would involve a product gauge group which is spontaneously broken.
Gauge interactions in terms of physical gauge bosons are canonical with respect
to massless gauge bosons as required by the exact gauge symmetry, but not so
with respect to massive ones; and furthermore they are generally asymmetric in
the two sets of gauge bosons. On noncommutative spacetime this already occurs
for the simplest model of U(1) x U(1). We examine whether the above feature in
gauge interactions can be perturbatively maintained in this model. We show by a
complete one loop analysis that all ultraviolet divergences are removable with
a few renormalization constants in a way consistent with the above structure.Comment: 24 pages, figures using axodraw; version 2: a new ref item [4] added
to cite efforts to all orders, typos fixed and minor rewordin
Green Function on the q-Symmetric Space SU_q(2)/U(1)
Following the introduction of the invariant distance on the non-commutative
C-algebra of the quantum group SU_q(2), the Green function and the Kernel on
the q-homogeneous space M=SU(2)_q/U(1) are derived. A path integration is
formulated. Green function for the free massive scalar field on the
non-commutative Einstein space R^1xM is presented.Comment: Plain Latex, 19
Holocentric Chromosomes of Luzula elegans Are Characterized by a Longitudinal Centromere Groove, Chromosome Bending, and a Terminal Nucleolus Organizer Region
The structure of holocentric chromosomes was analyzed in mitotic cells of Luzula elegans. Light and scanning electron microscopy observations provided evidence for the existence of a longitudinal groove along each sister chromatid. The centromere-specific histone H3 variant, CENH3, colocalized with this groove and with microtubule attachment sites. The terminal chromosomal regions were CENH3-negative. During metaphase to anaphase transition, L. elegans chromosomes typically curved to a sickle-like shape, a process that is likely to be influenced by the pulling forces of microtubules along the holocentric axis towards the corresponding microtubule organizing regions. A single pair of 45S rDNA sites, situated distal to Arabidopsis-telomere repeats, was observed at the terminal region of one chromosome pair. We suggest that the 45S rDNA position in distal centromere-free regions could be required to ensure chromosome stability. Copyright (C) 2011 S. Karger AG, Base
Insect Control and Dosage Effects in Transgenic Canola Containing a Synthetic Bacillus thuringiensis cryIAc Gene
Surveying Standard Model Flux Vacua on
We consider the SU(2)LxSU(2)R Standard Model brane embedding in an
orientifold of T6/Z2xZ2. Within defined limits, we construct all such Standard
Model brane embeddings and determine the relative number of flux vacua for each
construction. Supersymmetry preserving brane recombination in the hidden sector
enables us to identify many solutions with high flux. We discuss in detail the
phenomenology of one model which is likely to dominate the counting of vacua.
While Kahler moduli stabilization remains to be fully understood, we define the
criteria necessary for generic constructions to have fixed moduli.Comment: 30 pages, LaTeX, v2: added reference
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Using mobile devices and apps to support reflective learning about older people with dementia
There has been little research to develop computing technologies to support the care of people with dementia, in spite of the growing challenges that the condition poses for society. To design such technologies, an existing model of computer-support reflective learning was instantiated with findings from a pre-design study in one residential home. The result was a mobile device running an adapted enterprise social media app to support person-centred care. Evaluations of the device and app in two residential homes revealed that use of the app both motivated and increased different styles of care note recording, but little reflective learning was identified or reported. The results suggest the need for more comprehensive and flexible computer-based support for reflective learning about residents in their care – and new designs of this more comprehensive support are also introduced
First near-relativistic solar electron events observed by EPD onboard Solar Orbiter
Context. Solar Orbiter, launched in February 2020, started its cruise phase in June 2020, in coincidence with its first perihelion at 0.51 au from the
Sun. The in situ instruments onboard, including the Energetic Particle Detector (EPD), operate continuously during the cruise phase enabling the
observation of solar energetic particles.
Aims. In situ measurements of the first near-relativistic solar electron events observed in July 2020 by EPD are analyzed and the solar origins and
the conditions for the interplanetary transport of these particles investigated.
Methods. Electron observations from keV energies to the near-relativistic range were combined with the detection of type III radio bursts and
extreme ultraviolet (EUV) observations from multiple spacecraft in order to identify the solar origin of the electron events. Electron anisotropies
and timing as well as the plasma and magnetic field environment were evaluated to characterize the interplanetary transport conditions.
Results. All electron events were clearly associated with type III radio bursts. EUV jets were also found in association with all of them except
one. A diversity of time profiles and pitch-angle distributions was observed. Different source locations and different magnetic connectivity and
transport conditions were likely involved. The July 11 event was also detected by Wind, separated 107 degrees in longitude from Solar Orbiter.
For the July 22 event, the Suprathermal Electron and Proton (STEP) sensor of EPD allowed for us to not only resolve multiple electron injections
at low energies, but it also provided an exceptionally high pitch-angle resolution of a very anisotropic beam. This, together with radio observations
of local Langmuir waves suggest a very good magnetic connection during the July 22 event. This scenario is challenged by a high-frequency
occultation of the type III radio burst and a nominally non-direct connection to the source; therefore, magnetic connectivity requires further
investigation
Allopurinol and cardiovascular outcomes in patients with ischaemic heart disease : the ALL-HEART RCT and economic evaluation
Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 11/36/41) and is published in full in Health Technology Assessment; Vol. 28, No. 18. See the NIHR Funding and Awards website for further award information.Peer reviewe
A program of nurse algorithm-guided care for adult patients with acute minor illnesses in primary care
Background: Attention to patients with acute minor-illnesses requesting same-day consultation represents a major burden in primary care. The workload is assumed by general practitioners in many countries. A number of reports suggest that care to these patients may be provided, at in least in part, by nurses. However, there is scarce information with respect to the applicability of a program of nurse management for adult patients with acute minor-illnesses in large areas. The aim of this study is to assess the effectiveness of a program of nurse algorithm-guided care for adult patients with acute minor illnesses requesting same-day consultation in primary care in a largely populated area. Methods: A cross-sectional study of all adult patients seeking same day consultation for 16 common acute minor illnesses in a large geographical area with 284 primary care practices. Patients were included in a program of nurse case management using management algorithms. The main outcome measure was case resolution, defined as completion of the algorithm by the nurse without need of referral of the patient to the general practitioner. The secondary outcome measure was return to consultation, defined as requirement of new consultation for the same reason as the first one, in primary care within a 7-day period. Results: During a two year period (April 2009-April 2011), a total of 1,209,669 consultations were performed in the program. Case resolution was achieved by nurses in 62.5% of consultations. The remaining cases were referred to a general practitioner. Resolution rates ranged from 94.2% in patients with burns to 42% in patients with upper respiratory symptoms. None of the 16 minor illnesses had a resolution rate below 40%. Return to consultation during a 7-day period was low, only 4.6%. Conclusions: A program of algorithms-guided care is effective for nurse case management of patients requesting same day consultation for minor illnesses in primary care
A Method to Find Longevity-Selected Positions in the Mammalian Proteome
Evolutionary theory suggests that the force of natural selection decreases with age. To explore the extent to which this prediction directly affects protein structure and function, we used multiple regression to find longevity-selected positions, defined as the columns of a sequence alignment conserved in long-lived but not short-lived mammal species. We analyzed 7,590 orthologous protein families in 33 mammalian species, accounting for body mass, phylogeny, and species-specific mutation rate. Overall, we found that the number of longevity-selected positions in the mammalian proteome is much higher than would be expected by chance. Further, these positions are enriched in domains of several proteins that interact with one another in inflammation and other aging-related processes, as well as in organismal development. We present as an example the kinase domain of anti-Müllerian hormone type-2 receptor (AMHR2). AMHR2 inhibits ovarian follicle recruitment and growth, and a homology model of the kinase domain shows that its longevity-selected positions cluster near a SNP associated with delayed human menopause. Distinct from its canonical role in development, this region of AMHR2 may function to regulate the protein’s activity in a lifespan-specific manner
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