462 research outputs found
Birkhoff Theorem and Matter
Birkhoff's theorem for spherically symmetric vacuum spacetimes is a key
theorem in studying local systems in general relativity theory. However
realistic local systems are only approximately spherically symmetric and only
approximately vacuum. In a previous paper, we showed the theorem remains
approximately true in an approximately spherically symmetric vacuum space time.
In this paper we prove the converse case: the theorem remains approximately
true in a spherically symmetric, approximately vacuum space time.Comment: 7 pages, Revtex
Use of apomorphine in Parkinsonian patients with neuropsychiatric complications to oral treatment
Neuropsychiatric side effects often complicate anti-Parkinsonian therapy and pose a significant problem in the optimal management of idiopathic Parkinson's disease. Several publications report a relative lack of neuropsychiatric side effects in Parkinsonian patients treated with subcutaneous apomorphine. To investigate this further, we have used subcutaneous apomorphine to treat 12 non-demented IPD patients with previous oral drug-related neuropsychiatric problems. Treatment with apomorphine allowed alteration of anti-Parkinsonian medication and led to the abolition or reduction of neuropsychiatric complications in all patients. The mechanism remains unclear but may be due, in part, to a reduction in oral medication or a psychotropic action of apomorphine, possibly due to the piperidine moiety in its structure, or both
Relic Neutralino Densities and Detection Rates with Nonuniversal Gaugino Masses
We extend previous analyses on the interplay between nonuniversalities in the
gaugino mass sector and the thermal relic densities of LSP neutralinos, in
particular to the case of moderate to large tan beta. We introduce a set of
parameters that generalizes the standard unified scenario to cover the complete
allowed parameter space in the gaugino mass sector. We discuss the physical
significance of the cosmologically preferred degree of degeneracy between
charginos and the LSP and study the effect this degree of degeneracy has on the
prospects for direct detection of relic neutralinos in the next round of dark
matter detection experiments. Lastly, we compare the fine tuning required to
achieve a satisfactory relic density with the case of universal gaugino masses,
as in minimal supergravity, and find it to be of a similar magnitude. The
sensitivity of quantifiable measures of fine-tuning on such factors as the
gluino mass and top and bottom masses is also examined.Comment: Uses RevTeX; 14 pages, 16 figure
Power law enhancement of neutrino mixing angles in extra dimensions
We study the renormalization of the -type Majorana neutrino mass
operator in a scenario where there is a compactified extra dimension and the
fields involved correspond to only the standard model particles and their
Kaluza-Klein excitations. We observe that in a two flavour scenario, where one
of the neutrinos is necessarily , it is indeed possible to generate a
large mixing at 100 GeV starting from a very small mixing near the
ultra-violet cutoff 30 TeV. {\em En passant}, we also derive the Higgs
mass upper and lower limits from perturbative unitarity and stability of the
potential, respectively.Comment: Latex, 6 pages, one pslatex figure; v2: clarifying remarks added,
minor typos corrected, references updated, version to appear in Phys. Rev.
Patient and public involvement in cancer research: A scoping review.
Patient and public involvement (PPI) in research emphasizes the importance of doing research with, rather than for people with lived health/illness experience(s). The purpose of this scoping review is to investigate the breadth and depth of scientific literature on PPI in cancer research and to identify how is PPI applied and reported in cancer research.
We searched MEDLINE, Embase, CINAHL, and PsycInfo up to March 2022. All titles/abstracts and full-text results were screened by two reviewers. Data were analyzed and are presented in both narrative and tabular format.
We screened 22,009 titles/abstract, reviewed 375 full-text articles, of which 101 studies were included in this review. 66 papers applied PPI; 35 used co-design methodologies. PPI in cancer research in published research has increased steadily since 2015 and often includes those with a past diagnosis of cancer or relatives/informal caregivers. The most common applied methods were workshops or interviews. PPI was generally used at the level of consultation/advisor and occurred mainly in early stages of research. Costs related to PPI were mentioned in 25 papers and four papers described training provided for PPI.
Results of our review demonstrate the nature and extent of PPI expansion in cancer research. Researchers and research organizations entering the fray of PPI should consider planning and reporting elements such as the stage, level, and role type of PPI, as well as methods and strategies put in place to assure diversity. Furthermore, a thorough evaluation of whether all these elements meet the stated PPI purpose will help to grasp its impact on research outcomes.
Two patients participated in the stakeholder consultation as part of the scoping review methodology, contributed to the discussion on refining the results, and critically reviewed the manuscript. Both are co-authors of this manuscript
Motivating Weight Loss Among Black Adults in Relationships: Recommendations for Weight Loss Interventions
Background Black men and women have the highest rates of obesity in the United States. Behavioral weight loss programs incorporating intimate partners may be effective in combating obesity among this population. Yet, current participation in these programs is low. Identifying motivations and triggers to weight loss may provide insight in designing programs to increase participation.AimTo determine triggers and motivations for weight loss among Black men and women in committed relationships to inform development of weight loss interventions. Method Twenty semi-structured interviews, based on an integrated theoretical framework of interdependence and communal coping and the social cognitive theory, were conducted among Black heterosexual couples where one or both individuals intentionally lost ≥5% of their body weight in the last 6 months in a metropolitan region in a southern state. Interviews were transcribed and coded. Themes were identified following multi-rater coding and direct and conventional content analysis. Recommendations were developed from emergent themes. Results Among individuals with recent weight loss, personal relevancy and awareness (health awareness and self-awareness) were identified as personal triggers for weight loss initiation. Health concerns and appearance were general motivations among the total sample. Conclusion Emphasizing the impact of weight on daily functioning and quality of life, and increasing awareness of personal weight status and health consequences, may increase weight loss initiation and participation in weight loss programs among Black men and women in committed relationships. Findings also highlight strategies to improve recruitment and retention and guide intervention development and implementation for this population
On the Possibility of Optical Unification in Heterotic Strings
Recently J. Giedt discussed a mechanism, entitled optical unification,
whereby string scale unification is facilitated via exotic matter with
intermediate scale mass. This mechanism guarantees that a virtual MSSM
unification below the string scale is extrapolated from the running of gauge
couplings upward from M_Z^o when an intermediate scale desert is assumed. In
this letter we explore the possibility of optical unification within the
context of weakly coupled heterotic strings. In particular, we investigate this
for models of free fermionic construction containing the NAHE set of basis
vectors. This class is of particular interest for optical unification, because
it provides a standard hypercharge embedding within SO(10), giving the standard
k_Y = 5/3 hypercharge level, which was shown necessary for optical unification.
We present a NAHE model for which the set of exotic SU(3)_C
triplet/anti-triplet pairs, SU(2)_L doublets, and non-Abelian singlets with
hypercharge offers the possibility of optical unification. Whether this model
can realize optical unification is conditional upon these exotics not receiving
Fayet-Iliopoulos (FI) scale masses when a flat direction of scalar vacuum
expectation values is non-perturbatively chosen to cancel the FI D-term, xi,
generated by the anomalous U(1)-breaking Green-Schwarz-Dine-Seiberg-Wittten
mechanism. A study of perturbative flat directions and their phenomenological
implications for this model is underway.
This paper is a product of the NFS Research Experiences for Undergraduates
and the NSF High School Summer Science Research programs at Baylor University.Comment: 16 pages. Standard Late
Cold Nuclear Matter Effects on Dijet Productions in Relativistic Heavy-ion Reactions at LHC
We investigate the cold nuclear matter(CNM) effects on dijet productions in
high-energy nuclear collisions at LHC with the next-to-leading order
perturbative QCD. The nuclear modifications for dijet angular distributions,
dijet invariant mass spectra, dijet transverse momentum spectra and dijet
momentum imbalance due to CNM effects are calculated by incorporating EPS, EKS,
HKN and DS param-etrization sets of parton distributions in nucleus . It is
found that dijet angular distributions and dijet momentum imbalance are
insensitive to the initial-state CNM effects and thus provide optimal tools to
study the final-state hot QGP effects such as jet quenching. On the other hand,
the invariant mass spectra and the transverse momentum spectra of dijet are
generally enhanced in a wide region of the invariant mass or transverse
momentum due to CNM effects with a feature opposite to the expected suppression
because of the final-state parton energy loss effect in the QGP. The difference
of EPS, EKS, HKN and DS parametrization sets of nuclear parton distribution
functions is appreciable for dijet invariant mass spectra and transverse
momentum spectra at p+Pb collisions, and becomes more pronounced for those at
Pb+Pb reactions.Comment: 10 pages, 11 figure
The Other Side of Through: Young Breast Cancer Survivors’ Spectrum of Sexual and Reproductive Health Needs
The long-term reproductive health impact of cancer treatments is a concern for premenopausal women with a history of breast cancer. This study examined the unmet sexual and reproductive health needs of breast cancer survivors, as well as concordances and discordances in needs by childbearing status and race. We interviewed 17 women diagnosed with breast cancer between the ages of 18 and 45 years and living in North Carolina. To analyze these data, we used the Sort and Sift, Think and Shift© method, a multidimensional qualitative analysis approach. We learned that breast cancer survivors (a) received limited reproductive health information, (b) desired realistic expectations of conceiving postcancer, (c) struggled with adjusting to their altered physical appearance, and (d) had menopause symptoms that led to sexual health and quality of life issues. Breast cancer survivors are in need of and desire more education and resources to address their sexual and reproductive health concerns
Minimal Scenarios for Leptogenesis and CP Violation
The relation between leptogenesis and CP violation at low energies is
analyzed in detail in the framework of the minimal seesaw mechanism. Working,
without loss of generality, in a weak basis where both the charged lepton and
the right-handed Majorana mass matrices are diagonal and real, we consider a
convenient generic parametrization of the Dirac neutrino Yukawa coupling matrix
and identify the necessary condition which has to be satisfied in order to
establish a direct link between leptogenesis and CP violation at low energies.
In the context of the LMA solution of the solar neutrino problem, we present
minimal scenarios which allow for the full determination of the cosmological
baryon asymmetry and the strength of CP violation in neutrino oscillations.
Some specific realizations of these minimal scenarios are considered. The
question of the relative sign between the baryon asymmetry and CP violation at
low energies is also discussed.Comment: 36 pages, 5 figures; minor corrections and references updated. Final
version to appear in Phys. Rev.
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