The anomalous metallic state in the high-temperature superconducting cuprates is masked by superconductivity near a quantum critical point. Applying high magnetic fields to suppress superconductivity ...has enabled detailed studies of the normal state, yet the direct effect of strong magnetic fields on the metallic state is poorly understood. We report the high-field magnetoresistance of thin-film La
Sr
CuO
cuprate in the vicinity of the critical doping, 0.161 ≤
≤ 0.190. We find that the metallic state exposed by suppressing superconductivity is characterized by magnetoresistance that is linear in magnetic fields up to 80 tesla. The magnitude of the linear-in-field resistivity mirrors the magnitude and doping evolution of the well-known linear-in-temperature resistivity that has been associated with quantum criticality in high-temperature superconductors.
Marine volcaniclastic rocks in the Sierra Nevada preserve a critical record of silicic magmatism in the early Sierra Nevada volcanic arc, and this magmatic record provides precise minimum age ...constraints on subduction inception and tectonic evolution of the early Mesozoic Cordilleran convergent margin at this latitude. New zircon Pb/U ages from the Ritter Range pendant and regional correlations indicate arc inception no later than mid‐Triassic time between 37°N and 38°N. The regional first‐order felsic magma eruption rate as recorded by marine volcanic arc rocks was episodic, with distinct pulses of ignimbrite emplacement at ca. 221–216 and 174–167 Ma. Ignimbrites range from dacite to rhyolite in bulk composition, and are petrographically similar to modern arc‐type, monotonous intermediate dacite or phenocryst‐poor, low‐silica rhyolite. Zircon trace element geochemistry indicates that Jurassic silicic melts were consistently Ti‐enriched and light rare earth‐enriched and U‐depleted in comparison to Triassic melts of the juvenile arc, suggesting Jurassic silicic melts were hotter, drier, and derived from distinct lithospheric sources not tapped in the juvenile stage of arc construction. Pulses of ignimbrite deposition were coeval with granodioritic to granitic components of the underlying early Mesozoic Sierra Nevada batholith, suggesting explosive silicic volcanism and batholith construction were closely coupled at 1–2 million‐year time scales.
Key Points
Detrital zircons preserve age and trace element evidence of ignimbrite provenance
Zircons record >50 million years of early arc magmatic pulses and lull
Explosive volcanism and batholith construction were closely coupled at million‐year time scales
Concurrent chemoradiation with etoposide and cisplatin (EP/XRT) is standard treatment for inoperable stage III locally advanced non-small-cell lung cancer (LA-NSCLC). Consolidation docetaxel (D; ...Taxotere) after EP/XRT resulted in increased toxicity but no improvement in survival compared with observation (O). We report updated survival for the entire study population and include an analysis of efficacy and tolerability of EP/XRT with or without D in patients aged ≥ 70 years.
Hoosier Oncology Group LUN 01-24 enrolled 243 patients with LA-NSCLC and randomized 166 after EP/XRT to three cycles of D versus O. the trial was terminated after an analysis of the first 203 patients demonstrated futility of D.
Median survival time (MST) for the overall study population was 21.5 months, and 3-, 4-, and 5-year survival rates were 30.7%, 18.0%, and 13.9%, respectively. No differences in MST or 3-year survival were noted between D and O arms. Older patients had similar MST (17.1 versus 22.8 months for younger patients, P = 0.15) but higher rates of grade 3/4 toxicity and hospitalization during induction.
Consolidation docetaxel after EP/XRT does not improve survival in LA-NSCLC. Fit older adults with LA-NSCLC benefit from concurrent chemoradiation similarly as younger patients but experience higher rates of hospitalization and toxicity.
Hsp90 is required for the normal activity of steroid receptors, and in steroid receptor complexes it is typically bound to one of the immunophilin‐related co‐chaperones: the peptidylprolyl isomerases ...FKBP51, FKBP52 or CyP40, or the protein phosphatase PP5. The physiological roles of the immunophilins in regulating steroid receptor function have not been well defined, and so we examined in vivo the influences of immunophilins on hormone‐dependent gene activation in the Saccharomyces cerevisiae model for glucocorticoid receptor (GR) function. FKBP52 selectively potentiates hormone‐dependent reporter gene activation by as much as 20‐fold at limiting hormone concentrations, and this potentiation is readily blocked by co‐expression of the closely related FKBP51. The mechanism for potentiation is an increase in GR hormone‐binding affinity that requires both the Hsp90‐binding ability and the prolyl isomerase activity of FKBP52.
Epidemiology of Sarcopenia III, L. Joseph Melton; Khosla, Sundeep; Crowson, Cynthia S. ...
Journal of the American Geriatrics Society (JAGS),
June 2000, Letnik:
48, Številka:
6
Journal Article
Recenzirano
OBJECTIVES: To examine patterns of muscle mass change with aging and to estimate the prevalence of sarcopenia.
DESIGN: Cross‐sectional survey.
SETTING: Population‐based study in Rochester, Minnesota.
...PARTICIPANTS: Age‐stratified sample of men and women from the community.
MEASUREMENTS: Muscle mass estimated from total body scans by dual‐energy X‐ray absorptiometry. Sarcopenia was defined as muscle mass more than 2 standard deviations below the sex‐specific young‐normal mean.
RESULTS: Total lean body mass (exclusive of bone) and total skeletal muscle mass both were greater in men than women and declined linearly with age as judged from these cross‐sectional data. Adjustment for height reduced the gender difference. The age‐ and sex‐adjusted prevalence of sarcopenia varied from 6 to 15% among subjects 65 years of age or over, depending on the muscle mass parameter that was evaluated, but prevalence rates were quite sensitive to the normal values used to define cutoff levels. Subjects with sarcopenia appeared to have more physical limitations than the others.
CONCLUSIONS: Late in life, a substantial portion of the population reaches low levels of muscle mass that are associated with increased physical disability. However, additional efforts are needed to validate an operational definition of sarcopenia. J Am Geriatr Soc 48:625–630, 2000.
The storm surge associated with Hurricane Katrina caused tremendous damage along the Gulf Coast in Louisiana, Mississippi, and Alabama. Similar damage was observed subsequent to the Indian Ocean ...tsunami of December 26, 2004. In order to gain a better understanding of the performance of engineered structures subjected to coastal inundation due to tsunami or hurricane storm surge, the writers surveyed damage to bridges, buildings, and other coastal infrastructure subsequent to Hurricane Katrina. Numerous lessons were learned from analysis of the observed damage, and these are reported herein. A number of structures experienced significant structural damage due to storm surge and wave action. Structural members submerged during the inundation were subjected to significant hydrostatic uplift forces due to buoyancy, enhanced by trapped air pockets, and to hydrodynamic uplift forces due to wave action. Any floating or mobile object in the nearshore/onshore areas can become floating debris, affecting structures in two ways: impact and water damming. Foundation soils and foundation systems are at risk from shear- and liquefaction-induced scour, unless designed appropriately.
Celotno besedilo
Dostopno za:
DOBA, FGGLJ, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The heavy fermion intermetallic compound URu2Si2 exhibits a hidden-order phase below the temperature of 17.5 K, which supports both anomalous metallic behavior and unconventional superconductivity. ...While these individual phenomena have been investigated in detail, it remains unclear how they are related to each other and to what extent uranium f-electron valence fluctuations influence each one. Here we use ligand site substituted URu2Si(2-x)P(x) to establish their evolution under electronic tuning. We find that while hidden order is monotonically suppressed and destroyed for x≤0.035, the superconducting strength evolves non-monotonically with a maximum near x≈0.01 and that superconductivity is destroyed near x≈0.028. This behavior reveals that hidden order depends strongly on tuning outside of the U f-electron shells. It also suggests that while hidden order provides an environment for superconductivity and anomalous metallic behavior, it's fluctuations may not be solely responsible for their progression.
Abstract
Thermal transport of quantum magnets has elucidated the nature of low energy elementary excitations and complex interplay between those excited states via strong scattering of thermal ...carriers. BiCu
2
PO
6
is a unique frustrated spin-ladder compound exhibiting highly anisotropic spin excitations that contain both itinerant and localized dispersion characters along the
b
- and
a
-axes respectively. Here, we investigate thermal conductivity
κ
of BiCu
2
PO
6
under high magnetic fields (
H
) of up to 30 tesla. A dip-feature in
κ
, located at ~15 K at zero-
H
along all crystallographic directions, moves gradually toward lower temperature (
T
) with increasing
H
, thus resulting in giant suppression by a factor of ~30 near the critical magnetic field of
H
c
≅ 23.5 tesla. The giant
H-
and
T-
dependent suppression of
κ
can be explained by the combined result of resonant scattering of phononic heat carriers with magnetic energy levels and increased phonon scattering due to enhanced spin fluctuation at
H
c
, unequivocally revealing the existence of strong spin-phonon coupling. Moreover, we find an experimental indication that the remaining magnetic heat transport along the
b
-axis becomes almost gapless at the magnetic quantum critical point realized at
H
c
.
We present a combined experimental and theoretical study of the evolution of the Fermi surface of the anomalous superconductor Pb1−xTlxTe as a function of thallium concentration, drawing on a ...combination of magnetotransport measurements (Shubnikov–de Haas oscillations and the Hall coefficient), angle resolved photoemission spectroscopy, and density functional theory calculations of the electronic structure. Our results indicate that for Tl concentrations beyond a critical value, the Fermi energy coincides with resonant impurity states in Pb1−xTlxTe, and we rule out the presence of an additional valence band maximum at the Fermi energy. A comparison to nonsuperconducting Pb1−xNaxTe implies that the presence of these impurity states at the Fermi energy provides the enhanced pairing interaction and thus also the anomalously high temperature superconductivity in this material.
Summary
Osteoporosis (weak bones) is a disorder that has high morbidity, mortality, and healthcare utilization. Effective treatment is available for this disorder, but many patients choose not to ...start therapy. This is the first study showing an intervention that increases the initiation rates to medications for osteoporosis.
Introduction
One out of six patients prescribed an oral bisphosphonate does not initiate therapy, a phenomenon known as primary non-adherence. Reasons for bisphosphonate primary non-adherence have been identified, but not interventions that positively impact primary adherence rates. The purpose of this study is to determine the effectiveness of interactive voice response technology to improve oral bisphosphonate primary adherence.
Methods
This was a prospective, randomized controlled trial conducted in January–December 2014 at Kaiser Permanente Colorado, an integrated healthcare system. Adults with a new oral bisphosphonate prescription for osteoporosis or osteopenia which was not purchased within 14–20 days of being ordered were included. There were 127 and 118 patients in the intervention group and control groups, respectively. The intervention group received an interactive voice response phone call followed by a letter 1 week later if primary non-adherence continued, whereas the control group did not receive any outreach. The primary outcome was the proportion of patients who purchased their oral bisphosphonate within 25 days of randomization.
Results
There were 62/127 (48.8 %) intervention patients and 36/118 (30.5 %) control patients who purchased their bisphosphonate prescription within 25 days of randomization (OR = 2.17, 95 % CI 1.29–3.67). When adjusted for age, sex, history of bone mineral density scan and fracture, the odds ratio for intervention versus control group was 2.3 (95 % CI 1.34–3.94).
Conclusion
An interactive voice response phone call and follow-up letter significantly improved primary adherence to oral bisphosphonate therapy. Such an intervention could be considered for improving primary adherence rates to other medication classes.
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