1,217 research outputs found
Several small Josephson junctions in a Resonant Cavity: Deviation from the Dicke Model
We have studied quantum-mechanically a system of several small identical
Josephson junctions in a lossless single-mode cavity for different initial
states, under conditions such that the system is at resonance. This system is
analogous to a collection of identical atoms in a cavity, which is described
under appropriate conditions by the Dicke model. We find that our system can be
well approximated by a reduced Hamiltonian consisting of two levels per
junction. The reduced Hamiltonian is similar to the Dicke Hamiltonian, but
contains an additional term resembling a dipole-dipole interaction between the
junctions. This extra term arises when states outside the degenerate group are
included via degenerate second-order (L\"{o}wdin) perturbation theory. As in
the Dicke model, we find that, when N junctions are present in the cavity, the
oscillation frequency due to the junction-cavity interaction is enhanced by
. The corresponding decrease in the Rabi oscillation period may cause
it to be smaller than the decoherence time due to dissipation, making these
oscillations observable. Finally, we find that the frequency enhancement
survives even if the junctions differ slightly from one another, as expected in
a realistic system.Comment: 11 pages. To be published in Phys. Rev.
Archeological Significance Testing at 41BX17/271, the Granberg Site: A Multi-Component Site along the Salado Creek in Bexar County, Texas
The Center for Archaeological Research (CAR) of The University of Texas at San Antonio conducted archeological significance testing at 41BX17, the Granberg Site, from January to March 2006. The testing was conducted for the Texas Department of Transportation, Environmental Affairs Division (TxDOT-ENV). The Granberg Site sits on the eastern flood terrace of the Salado Creek south of Loop 410 in San Antonio, Bexar County, Texas. Planned road improvements including installation of a storm sewer line and a water main prompted the need to assess whether (1) cultural deposits including human remains still exist after previous testing and (2) if the deposits contribute to the site’s National Register of Historic Places eligibility. The archeological work was conducted under Texas Antiquities Permit No. 4010. Steve A. Tomka served as Principal Investigator and Jennifer Thompson served as Project Archeologist.
Fieldwork included mechanical auger boring and backhoe trenching to determine the horizontal extent of the site boundaries within the median of Loop 410 eastbound. Sixteen 1-x-1-m units were excavated to determine the distribution and integrity of the cultural deposits and to locate any possible burials that may still exist at the site. Materials recovered included burned rock features, chipped stone artifacts, animal bone, snail and mussel shell and charred plant remains. The distribution of the artifacts, the geomorphic investigations, the radiocarbon assays, and temporally diagnostic artifacts indicate the presence of Middle and Late Archaic archeological materials with good stratigraphic integrity. The Granberg Site was determined to be ineligible for the National Register of Historic Places. Following the completion of eligibility testing efforts, the TxDOT directed the CAR to develop a research design linking the data recovered from the various excavations at the Granberg Site with research goals. The CAR developed the research design (Munoz et al. 2007) under Work Authorization No. 57513SA005 with Cynthia M. Munoz serving as Project Archeologist.
At roughly the time of the research design implementation, the CAR was the recipient of a donation of a collection of commingled human skeletal remains recovered from the Granberg Site. These remains were recovered from 41BX17/271 in 1962 by Harvey Kohnitz, an avocational archeologist, without knowledge or permission from the Texas Highway Department. The remains were stored at the Kohnitz home until his son, Mark Kohnitz, donated them to the CAR in 2007. An osteological analysis was conducted at the CAR laboratory during February 2008 for TxDOT, under Work Authorization No. 57513SA005 Supplemental Work Authorization No. 4. The results of this analysis are reported in Appendix H of this report. The commingled remains will be curated the CAR and all required documents, including an inventory, will be submitted to the National Park Service National NAGPRA Program to fulfill all obligations pertaining to the NAGPRA laws.
All artifacts collected during this project and all project-associated documentation are permanently curated at the CAR according to Texas Historical Commission guidelines
Lithium in the Intermediate-Age Open Cluster, NGC 3680
High-dispersion spectra centered on the Li 6708 A line have been obtained for
70 potential members of the open cluster NGC 3680, with an emphasis on stars in
the turnoff region. A measurable Li abundance has been derived for 53 stars, 39
of which have radial velocities and proper motions consistent with cluster
membership. After being transferred to common temperature and abundance scales,
previous Li estimates have been combined to generate a sample of 49 members, 40
of which bracket the cluster Li-dip. Spectroscopic elemental analysis of 8
giants and 5 turnoff stars produces [Fe/H] = -0.17 +/- 0.07 (sd) and -0.07 +/-
0.02 (sd), respectively. We also report measurements of Ca, Si and Ni which are
consistent with scaled-solar ratios within the errors. Adopting [Fe/H] = -0.08
(Sect. 3.6), Y^2 isochrone comparisons lead to an age of 1.75 +/- 0.10 Gyr and
an apparent modulus of (m-M) = 10.30 +/- 0.15 for the cluster, placing the
center of the Li-dip at 1.35 +/- 0.03 solar masses. Among the giants, 5 of 9
cluster members are now known to have measurable Li with A(Li) near 1.0. A
combined sample of dwarfs in the Hyades and Praesepe is used to delineate the
Li-dip profile at 0.7 Gyr and [Fe/H] = +0.15, establishing its center at 1.42
+/- 0.02 solar masses and noting the possible existence of secondary dip on its
red boundary. When evolved to the typical age of the clusters NGC 752, IC 4651
and NGC 3680, the Hyades/Praesepe Li-dip profile reproduces the observed
morphology of the combined Li-dip within the CMD's of the intermediate-age
clusters while implying a metallicity dependence for the central mass of the
Li-dip given by Mass = (1.38 +/-0.04) + (0.4 +/- 0.2)[Fe/H]. The implications
of the similarity of the Li-dichotomy among giants in NGC 752 and IC 4651 and
the disagreement with the pattern among NGC 3680 giants are discussed.Comment: Latex ms. is 56 pages, including 10 figures and 4 tables. Accepted
for the Astronomical Journa
WIYN Open Cluster Study. XXXIX. Abundances in NGC 6253 from HYDRA Spectroscopy of the Li 6708 A Region
High-dispersion spectra of 89 potential members of the old, super-metal-rich
open cluster, NGC 6253, have been obtained with the HYDRA multi-object
spectrograph. Based upon radial-velocity measurements alone, 47 stars at the
turnoff of the cluster color-magnitude diagram (CMD) and 18 giants are
identified as potential members. Five turnoff stars exhibit evidence of
binarity while proper-motion data eliminates two of the dwarfs as members. The
mean cluster radial velocity from probable single-star members is -29.4 +/- 1.3
km/sec (sd). A discussion of the current estimates for the cluster reddening,
derived independently of potential issues with the BV cluster photometry, lead
to an adopted reddening of E(B-V) = 0.22 +/- 0.04. From equivalent width
analyses of 38 probable single-star members near the CMD turnoff, the weighted
average abundances are found to be [Fe/H] = +0.43 +/- 0.01, [Ni/H] = +0.53 +/-
0.02 and [Si/H] = +0.43 (+0.03,-0.04), where the errors refer to the standard
errors of the weighted mean. Weak evidence is found for a possible decline in
metallicity with increasing luminosity among stars at the turnoff. We discuss
the possibility that our turnoff stars have been affected by microscopic
diffusion. For 15 probable single-star members among the giants, spectrum
synthesis leads to abundances of +0.46 (+0.02,-0.03) for [Fe/H]. While less
than half the age of NGC 6791, NGC 6253 is at least as metal-rich and, within
the uncertainties, exhibits the same general abundance pattern as that typified
by super-metal-rich dwarfs of the galactic bulge.Comment: 5 Tables, 9 figures, 45 page
Novel methods for managing freshwater refuges against climate change in southern Australia. Final Report. National Climate Change Adaptation Research Facility
Recommended from our members
Rapid progression of prostate cancer in men with a BRCA2 mutation.
Men with BRCA2 mutations have been found to be at increased risk of developing prostate cancer. There is a recent report that BRCA2 carriers with prostate cancer have poorer survival than noncarrier prostate cancer patients. In this study, we compared survival of men with a BRCA2 mutation and prostate cancer with that of men with a BRCA1 mutation and prostate cancer. We obtained the age at diagnosis, age at death or current age from 182 men with prostate cancer from families with a BRCA2 mutation and from 119 men with prostate cancer from families with a BRCA1 mutation. The median survival from diagnosis was 4.0 years for men with a BRCA2 mutation vs 8.0 years for men with a BRCA1 mutation, and the difference was highly significant (P<0.01). It may be important to develop targeted chemotherapies to treat prostate cancer in men with a BRCA2 mutation
Safety Outcomes During Pediatric GH Therapy : Final Results From the Prospective GeNeSIS Observational Program
Altres ajuts: Financial Support: GeNeSIS was sponsored by Eli Lilly and Company (Indianapolis, IN). In compliance with the Uniform Requirements for Manuscripts, established by the International Committee of Medical Journal Editors, the sponsor of this study did not impose any impediment, directly or indirectly, on the publication of the study's results. Disclosure Summary: C.J.C. and N.J. are employees and stockholders ofEliLilly and Company (Indianapolis, IN).W.F.B. and A.G.Z. are former employees and are stockholders of Lilly. C.L.D., T.H., M.M., and R.G.R. are former members of the GeNeSIS International Advisory Board; S.L., J.P.S., A.R.-U., and M.P. have served as regional advisors. B.P. has consulted for Eli Lilly Italia SpA, and E.C. has received grant support from Lilly. W.F.B. also reports heis aconsultant forAmmonett Pharma,Lilly Germany, and Merck KGaA Darmstadt. C.L.D. also reports receipt of grants, consultancy honoraria, and speaker fees from Lilly,EMD Serono, and Sandoz; grants fromOpko Prolor, Pfizer, and Versatis; honoraria and speaker fees from Roche; honoraria from Pfizer; and speaker fees from Novo Nordisk. The remaining authors have nothing to disclose.Safety concerns have been raised regarding premature mortality, diabetes, neoplasia, and cerebrovascular disease in association with GH therapy. To assess incidence of key safety outcomes. Prospective, multinational, observational study (1999 to 2015). A total of 22,311 GH-treated children from 827 investigative sites in 30 countries. Children with growth disorders. GH treatment. Standardized mortality ratio (SMR) and standardized incidence ratio (SIR) with 95% CIs for mortality, diabetes, and primary cancer using general population registries. Predominant short stature diagnoses were GH deficiency (63%), idiopathic short stature (13%), and Turner syndrome (8%), with mean ± SD follow-up of 4.2 ± 3.2 years (∼92,000 person-years [PY]). Forty-two deaths occurred in patients with follow-up, with an SMR (95% CI) of 0.61 (0.44, 0.82); the SMR was elevated for patients with cancer-related organic GH deficiency [5.87 (3.21, 9.85)]. Based on 18 cases, type 2 diabetes mellitus (T2DM) risk was elevated [SIR: 3.77 (2.24, 5.96)], but 72% had risk factors. In patients without cancer history, 14 primary cancers were observed [SIR: 0.71 (0.39, 1.20)]. Second neoplasms occurred in 31 of 622 cancer survivors [5.0%; 10.7 (7.5, 15.2) cases/1000 PY] and intracranial tumor recurrences in 67 of 823 tumor survivors [8.1%; 16.9 (13.3, 21.5) cases/1000 PY]. All three hemorrhagic stroke cases had risk factors. GeNeSIS (Genetics and Neuroendocrinology of Short Stature International Study) data support the favorable safety profile of pediatric GH treatment. Overall risk of death or primary cancer was not elevated in GH-treated children, and no hemorrhagic strokes occurred in patients without risk factors. T2DM incidence was elevated compared with the general population, but most cases had diabetes risk factors. Safety of GH therapy was assessed in a pediatric observational study. Death and primary cancer rates were not higher than in the general population; T2DM rate was higher owing to risk factors
Factors Associated with Self and Informant Ratings of the Quality of Life of People with Dementia Living in Care Facilities: A Cross Sectional Study
There is no consensus regarding the optimal approach to assessment of the quality of life of people with dementia. We undertook the present study to describe and determine the factors associated with ratings of the quality of life of a cohort of people with dementia living in a residential care facility.351 people with dementia living in residential care facilities, and their staff and family informants participated in this cross sectional observational study. Quality of life was measured using self (Quality of Life in Alzheimer's Disease [QoL-AD] scale), and informant (QoL-AD and Alzheimer's Disease Related QoL Scale) reports. 226 people (64%) with dementia (median MMSE 17; 12-21) were able to self rate the QoL-AD scale and these subjects' ratings were compared to ratings by staff and family. Both staff and family informant ratings of the QoL-AD underestimated self ratings (mean difference -7.8, 95% CI -8.8, -6.7 for staff rated QoL-AD; and mean difference -7.2, 95% CI -8.5, -6.0 for family rated QoL-AD). Self ratings of QoL were lower among people who were restrained, had fallen or had pain. Informant ratings of the QoL of the participants with dementia were consistently and significantly lower for people with severe cognitive impairment, who had fallen, had presence of neuropsychiatric symptoms, or where care giver distress was present. Documented restraint, reported pain and neuropsychiatric symptoms were independently associated with lower self rating of the QoL-AD in multivariate models. Cognitive impairment, case conferencing, hospitalizations and neuropsychiatric symptoms were found to be independently associated with staff rated ADRQL.The majority of people with dementia living in residential care facilities can rate their own QoL. Informant ratings underestimate self ratings of QoL of people with dementia, and appear to be associated with factors which are not associated with self ratings
Emergence of Respiratory Streptococcus agalactiae Isolates in Cystic Fibrosis Patients
Streptococcus agalactiae is a well-known pathogen for neonates and immunocompromized adults. Beyond the neonatal period, S. agalactiae is rarely found in the respiratory tract. During 2002–2008 we noticed S. agalactiae in respiratory secretions of 30/185 (16%) of cystic fibrosis (CF) patients. The median age of these patients was 3–6 years older than the median age CF patients not harboring S. agalactiae. To analyze, if the S. agalactiae isolates from CF patients were clonal, further characterization of the strains was achieved by capsular serotyping, surface protein determination and multilocus sequence typing (MLST). We found a variety of sequence types (ST) among the isolates, which did not substantially differ from the MLST patterns of colonizing strains from Germany. However serotype III, which is often seen in colonizing strains and invasive infections was rare among CF patients. The emergence of S. agalactiae in the respiratory tract of CF patients may represent the adaptation to a novel host environment, supported by the altered surfactant composition in older CF patients
A Cluster-Randomised Trial of Staff Education to Improve the Quality of Life of People with Dementia Living in Residential Care: The DIRECT Study
BACKGROUND: The Dementia In Residential care: EduCation intervention Trial (DIRECT) was conducted to determine if delivery of education designed to meet the perceived need of GPs and care staff improves the quality of life of participants with dementia living in residential care. METHODOLOGY/PRINCIPAL FINDINGS: This cluster-randomised controlled trial was conducted in 39 residential aged care facilities in the metropolitan area of Perth, Western Australia. 351 care facility residents aged 65 years and older with Mini-Mental State Examination ≤ 24, their GPs and facility staff participated. Flexible education designed to meet the perceived needs of learners was delivered to GPs and care facility staff in intervention groups. The primary outcome of the study was self-rated quality of life of participants with dementia, measured using the QOL-Alzheimer's Disease Scale (QOL-AD) at 4 weeks and 6 months after the conclusion of the intervention. Analysis accounted for the effect of clustering by using multi-level regression analysis. Education of GPs or care facility staff did not affect the primary outcome at either 4 weeks or 6 months. In a post hoc analysis excluding facilities in which fewer than 50% of staff attended an education session, self-rated QOL-AD scores were 6.14 points (adjusted 95%CI 1.14, 11.15) higher at four-week follow-up among residents in facilities randomly assigned to the education intervention. CONCLUSION: The education intervention directed at care facilities or GPs did not improve the quality of life ratings of participants with dementia as a group. This may be explained by the poor adherence to the intervention programme, as participants with dementia living in facilities where staff participated at least minimally seemed to benefit. TRIAL REGISTRATION: ANZCTR.org.au ACTRN12607000417482
- …