NiO is a p-type wide bandgap semiconductor of use in various electronic devices ranging from solar cells to transparent transistors. Understanding and improving its optical and transport properties ...have been of considerable interest. In this work, we have investigated the effect of Li doping on the electronic, optical and transport properties of NiO epitaxial thin films grown by pulsed laser deposition. We show that Li doping significantly increases the p-type conductivity of NiO, but all the films have relatively low room-temperature mobilities (<0.05 cm
2
V
−1
s
−1
). The conduction mechanism is better described by small-polaron hoping model in the temperature range of 200 K <
T
< 330 K, and variable range hopping at
T
< 200 K. A combination of X-ray photoemission and O K-edge X-ray absorption spectroscopic investigations reveal that the Fermi level gradually shifts toward the valence band maximum (VBM) and a new hole state develops with Li doping. Both the VBM and hole states are composed of primarily Zhang-Rice bound states, which accounts for the small polaron character (low mobility) of hole conduction. Our work provides guidelines for the search for p-type oxide materials and device optimization.
NiO is a p-type wide bandgap semiconductor of use in various electronic devices ranging from solar cells to transparent transistors. This work reports the controlling of conductivity and increase of work functions by Li doping.
First measurements of the in-flight shape of imploding inertial confinement fusion (ICF) capsules at the National Ignition Facility (NIF) were obtained by using two-dimensional x-ray radiography. The ...sequence of area-backlit, time-gated pinhole images is analyzed for implosion velocity, low-mode shape and density asymmetries, and the absolute offset and center-of-mass velocity of the capsule shell. The in-flight shell is often observed to be asymmetric even when the concomitant core self-emission is round. A ∼ 15 μm shell asymmetry amplitude of the Y(40) spherical harmonic mode was observed for standard NIF ICF hohlraums at a shell radius of ∼ 200 μm (capsule at ∼ 5× radial compression). This asymmetry is mitigated by a ∼ 10% increase in the hohlraum length.
The Last Glacial Termination Denton, G. H.; Anderson, R. F.; Toggweiler, J. R. ...
Science (American Association for the Advancement of Science),
06/2010, Letnik:
328, Številka:
5986
Journal Article
Recenzirano
A major puzzle of paleoclimatology is why, after a long interval of cooling climate, each late Quaternary ice age ended with a relatively short warming leg called a termination. We here offer a ...comprehensive hypothesis of how Earth emerged from the last global ice age. A prerequisite was the growth of very large Northern Hemisphere ice sheets, whose subsequent collapse created stadial conditions that disrupted global patterns of ocean and atmospheric circulation. The Southern Hemisphere westerlies shifted poleward during each northern stadial, producing pulses of ocean upwelling and warming that together accounted for much of the termination in the Southern Ocean and Antarctica. Rising atmospheric CO₂ during southern upwelling pulses augmented warming during the last termination in both polar hemispheres.
The El Niño—Southern Oscillation (ENSO) drives large changes in global climate patterns from year to year, yet its sensitivity to continued anthropogenic greenhouse forcing is uncertain. We analyzed ...fossil coral reconstructions of ENSO spanning the past 7000 years from the Northern Line Islands, located in the center of action for ENSO. The corals document highly variable ENSO activity, with no evidence for a systematic trend in ENSO variance, which is contrary to some models that exhibit a response to insolation forcing over this same period. Twentieth-century ENSO variance is significantly higher than average fossil coral ENSO variance but is not unprecedented. Our results suggest that forced changes in ENSO, whether natural or anthropogenic, may be difficult to detect against a background of large internal variability.
Abstract
STUDY QUESTION
Is there a temporal relationship between endometriosis and infertility?
SUMMARY ANSWER
Endometriosis is associated with a higher risk of subsequent infertility, but only among ...women age <35 years.
WHAT IS KNOWN ALREADY
Endometriosis is the most commonly observed gynecologic pathology among infertile women undergoing laparoscopic examination. Whether endometriosis is a cause of infertility or an incidental discovery during the infertility examination is unknown.
STUDY DESIGN, SIZE, DURATION
This study included data collected from 58 427 married premenopausal female nurses <40 years of age from 1989 to 2005, who are participants of the Nurses' Health Study II prospective cohort.
PARTICIPANTS/MATERIALS, SETTING, METHODS
Our exposure was laparoscopically confirmed endometriosis. Multivariate Cox proportional hazards regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for infertility risk (defined as attempting to conceive for >12 months) among women with and without endometriosis.
MAIN RESULTS AND THE ROLE OF CHANCE
We identified 4612 incident cases of infertility due to any cause over 362 219 person-years of follow-up. Compared with women without a history of endometriosis, women with endometriosis had an age-adjusted 2-fold increased risk of incident infertility (HR = 2.12, 95% CI = 1.76–2.56) that attenuated slightly after accounting for parity. The relationship with endometriosis was only observed among women <35 years of age (multivariate HR <35 years = 1.77, 95% CI = 1.46–2.14; multivariate HR 35–39 years = 1.20, 95% CI = 0.94–1.53; P-interaction = 0.008). Risk of primary versus secondary infertility was similar subsequent to endometriosis diagnosis. Among women with primary infertility, 50% became parous after the endometriosis diagnosis, and among all women with endometriosis, 83% were parous by age 40 years.
LIMITATIONS, REASONS FOR CAUTION
We did not have information on participants' intentions to conceive, but by restricting the analytic population to married women we increased the likelihood that pregnancies were planned (and therefore infertility would be recognized). Women in our cohort with undiagnosed asymptomatic endometriosis will be misclassified as unexposed. However, the small proportion of these women are diluted among the >50 000 women accurately classified as endometriosis-free, minimizing the impact of exposure misclassification on the effect estimates.
WIDER IMPLICATIONS OF THE FINDINGS
This study supports a temporal association between endometriosis and infertility risk. Our prospective analysis indicates a possible detection bias in previous studies, with our findings suggesting that the infertility risk posed by endometriosis is about half the estimates observed in cross-sectional analyses.
STUDY FUNDING/COMPETING INTERESTS
This work was supported by the National Institutes of Health (grant numbers: UM1 CA176726, HD52473, HD57210, T32DK007703, T32HD060454, K01DK103720). We have no competing interests to declare.
We report the detection of an ultra-bright fast radio burst (FRB) from a modest, 3.4-day pilot survey with the Australian Square Kilometre Array Pathfinder. The survey was conducted in a wide-field ...fly's-eye configuration using the phased-array-feed technology deployed on the array to instantaneously observe an effective area of 160 deg2, and achieve an exposure totaling 13200 deg2 hr . We constrain the position of FRB 170107 to a region in size (90% containment) and its fluence to be 58 6 Jy ms. The spectrum of the burst shows a sharp cutoff above 1400 MHz, which could be due to either scintillation or an intrinsic feature of the burst. This confirms the existence of an ultra-bright ( Jy ms) population of FRBs.
Constraint-induced movement therapy (CIMT) is among the most developed training approaches for motor restoration of the upper extremity (UE).
Very Early Constraint-Induced Movement during Stroke ...Rehabilitation (VECTORS) was a single-blind phase II trial of CIMT during acute inpatient rehabilitation comparing traditional UE therapy with dose-matched and high-intensity CIMT protocols. Participants were adaptively randomized on rehabilitation admission, and received 2 weeks of study-related treatments. The primary endpoint was the total Action Research Arm Test (ARAT) score on the more affected side at 90 days after stroke onset. A mixed model analysis was performed.
A total of 52 participants (mean age 63.9 +/- 14 years) were randomized 9.65 +/- 4.5 days after onset. Mean NIHSS was 5.3 +/- 1.8; mean total ARAT score was 22.5 +/- 15.6; 77% had ischemic stroke. Groups were equivalent at baseline on all randomization variables. As expected, all groups improved with time on the total ARAT score. There was a significant time x group interaction (F = 3.1, p < 0.01), such that the high intensity CIT group had significantly less improvement at day 90. No significant differences were found between the dose-matched CIMT and control groups at day 90. MRI of a subsample showed no evidence of activity-dependent lesion enlargement.
Constraint-induced movement therapy (CIMT) was equally as effective but not superior to an equal dose of traditional therapy during inpatient stroke rehabilitation. Higher intensity CIMT resulted in less motor improvement at 90 days, indicating an inverse dose-response relationship. Motor intervention trials should control for dose, and higher doses of motor training cannot be assumed to be more beneficial, particularly early after stroke.
A 50 kyr‐long exceptionally well‐dated and highly resolved stalagmite oxygen (δ18O) and carbon (δ13C) isotope record from Sofular Cave in northwestern Turkey helps to further improve the dating of ...Greenland Interstadials (GI) 1, and 3–12. Timing of most GI in the Sofular record is consistent within ±10 to 300 years with the “iconic” Hulu Cave record. Larger divergences (>500 years) between Sofular and Hulu are only observed for GI 4 and 7. The Sofular record differs from the most recent NGRIP chronology by up to several centuries, whereas age offsets do not increase systematically with depth. The Sofular record also reveals a rapid and sensitive climate and ecosystem response in the eastern Mediterranean to GI, whereas a phase lag of ∼100 years between climate and full ecosystem response is evident. Finally, results of spectral analyses of the Sofular isotope records do not support a 1,470‐year pacing of GI.
This manuscript describes the energy and water components of a new community land surface model called the Joint UK Land Environment Simulator (JULES). This is developed from the Met Office Surface ...Exchange Scheme (MOSES). It can be used as a stand alone land surface model driven by observed forcing data, or coupled to an atmospheric global circulation model. The JULES model has been coupled to the Met Office Unified Model (UM) and as such provides a unique opportunity for the research community to contribute their research to improve both world-leading operational weather forecasting and climate change prediction systems. In addition JULES, and its forerunner MOSES, have been the basis for a number of very high-profile papers concerning the land-surface and climate over the last decade. JULES has a modular structure aligned to physical processes, providing the basis for a flexible modelling platform.
Summary Background Animals can act as a reservoir and source for the emergence of novel meticillin-resistant Staphylococcus aureus (MRSA) clones in human beings. Here, we report the discovery of a ...strain of S aureus (LGA251) isolated from bulk milk that was phenotypically resistant to meticillin but tested negative for the mecA gene and a preliminary investigation of the extent to which such strains are present in bovine and human populations. Methods Isolates of bovine MRSA were obtained from the Veterinary Laboratories Agency in the UK, and isolates of human MRSA were obtained from diagnostic or reference laboratories (two in the UK and one in Denmark). From these collections, we searched for mecA PCR-negative bovine and human S aureus isolates showing phenotypic meticillin resistance. We used whole-genome sequencing to establish the genetic basis for the observed antibiotic resistance. Findings A divergent mecA homologue ( mecALGA251 ) was discovered in the LGA251 genome located in a novel staphylococcal cassette chromosome mec element, designated type-XI SCC mec . The mecALGA251 was 70% identical to S aureus mecA homologues and was initially detected in 15 S aureus isolates from dairy cattle in England. These isolates were from three different multilocus sequence type lineages (CC130, CC705, and ST425); spa type t843 (associated with CC130) was identified in 60% of bovine isolates. When human mecA -negative MRSA isolates were tested, the mecALGA251 homologue was identified in 12 of 16 isolates from Scotland, 15 of 26 from England, and 24 of 32 from Denmark. As in cows, t843 was the most common spa type detected in human beings. Interpretation Although routine culture and antimicrobial susceptibility testing will identify S aureus isolates with this novel mecA homologue as meticillin resistant, present confirmatory methods will not identify them as MRSA. New diagnostic guidelines for the detection of MRSA should consider the inclusion of tests for mecALGA251. Funding Department for Environment, Food and Rural Affairs, Higher Education Funding Council for England, Isaac Newton Trust (University of Cambridge), and the Wellcome Trust.
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