The type I X-ray burster and dipper 4U1915-05 (also known as XB1916-053) was monitored by the Rossi X-ray Timing Explorer between February and October, 1996. The source was observed in various ...spectral states; the highest luminosity state (LX ~ 1.5 10^37 ergs/s, 10 kpc, 1-20 keV) is associated with a soft spectrum, whereas for the lower luminosity state (down to ~5 10^36 ergs/s) the spectrum is significantly harder. Using the high time resolution data provided by the Proportional Counter Array (PCA), we have discovered High-Frequency Quasi-Periodic Oscillations (HFQPOs) in the persistent X-ray emission of 4U1915-05 while its luminosity was ~8 10^36 ergs/s. The QPO frequency ranges from 600 Hz up to ~1000 Hz, with typical Full Width at Half Maximum (FWHM) ~50-100 Hz and Root Mean Squared (RMS) values 15%. In addition, by using the ``shift and add'' technique, we have detected a twin HFQPO (5.5 sigma level) separated from the main peak by ~355 Hz. 4U1915-05 is the eighth Atoll source displaying simultaneous twin HFQPOs. Based on current knowledge of HFQPO sources, our observations suggest that 4U1915-05 might contain a 2.8 (or 5.6) millisecond rotating neutron star.
We have detected quasi-periodic oscillations (QPOs) near 1 kHz from the low
mass X-ray binary 4U 0614+091 in observations with XTE. The observations span
several months and sample the source over a ...large range of X-ray luminosity. In
every interval QPOs are present above 400 Hz with fractional RMS amplitudes
from 3 to 12%. At high count rates, two high frequency QPOs are detected
simultaneously. The difference of their frequency centroids is consistent with
323 Hz in all observations. During one interval a third signal is detected at
328 +/- 2 Hz. This suggests the system has a stable `clock' which is most
likely the neutron star with spin period 3.1 msec. Thus, our observations and
those of another neutron star system by Strohmayer et al. (1996) provide the
first evidence for millisecond pulsars within low-mass X-ray binary systems and
reveal the `missing-link' between millisecond radiopulsars and the late stages
of binary evolution in low mass X-ray binaries (Alpar et al. 1982). We suggest
that the kinematics of the magnetospheric beat-frequency model (Alpar and
Shaham 1985) applies to these QPOs. In this interpretation the high frequency
signal is associated with the Keplerian frequency of the inner accretion disk
and the lower frequency `beat' signal arises from the differential rotation
frequency of the inner disk and the spinning neutron star. Assuming the high
frequency QPO is a Keplerian orbital frequency for the accretion disk, we find
a maximum mass of 1.9 solar masses and a maximum radius of 17 km for the
neutron star.
We present the first results on the identifications of a medium sensitivity
survey (X-ray flux limit 2E-14 erg/cm2/s in the 0.5-4.5 keV band) at high
galactic latitude (|b|>20 deg) carried out with ...the XMM-Newton X-ray
observatory within the AXIS observing programme. This study is being conducted
as part of the XMM-Newton Survey Science Centre activities towards the
identification of the sources in the X-ray serendipitous sky survey. The sample
contains 29 X-ray sources in a solid angle of 0.26deg2 (source density 113 +/-
21 sources/deg2), out of which 27 (93%) have been identified. The majority of
the sources are broad-line AGN (19), followed by narrow emission line X-ray
emitting galaxies (6, all of which turn out to be AGN), 1 nearby non-emission
line galaxy (NGC 4291) and 1 active coronal star. Among the identified sources
we find 2 broad-absorption line QSOs (z~1.8 and z~1.9), which constitute ~10%
of the AGN population at this flux level, similar to optically selected
samples. Identifications of a further 10 X-ray sources fainter than our survey
limit are also presented.
Objective
To better understand mental health service users’ experiences of stigma and discrimination in different settings.
Method
An annual telephone survey of people with a mental health diagnosis ...conducted to evaluate the Time to Change antistigma campaign in England. Of 985 people who participated in 2013, 84 took part in a qualitative interview which was audio recorded. Of these, 50 interviews were transcribed and thematically analysed to explore accounts of discrimination. We analysed common types of behaviour; motivations ascribed to the discriminators; expectations of what fair treatment would have been; and the impact of discrimination on participants.
Results
Discrimination was most common in five contexts: welfare benefits, mental health care, physical health care, family and friends. Participants often found it hard to assess whether a behaviour was discriminatory or not. Lack of support, whether by public services or by friends and family, was often experienced as discrimination, reflecting an expectation that positive behaviours and reasonable adjustments should be offered in response to mental health needs.
Conclusion
The impact of discrimination across different settings was often perceived by participants as aggravating their mental health, and there is thus a need to treat discrimination as a health issue, not just a social justice issue.
Summary Background Vascular-targeted photodynamic therapy, a novel tissue-preserving treatment for low-risk prostate cancer, has shown favourable safety and efficacy results in single-arm phase 1 and ...2 studies. We compared this treatment with the standard of care, active surveillance, in men with low-risk prostate cancer in a phase 3 trial. Methods This randomised controlled trial was done in 47 European university centres and community hospitals. Men with low-risk, localised prostate cancer (Gleason pattern 3) who had received no previous treatment were randomly assigned (1:1) to vascular-targeted photodynamic therapy (4 mg/kg padeliporfin intravenously over 10 min and optical fibres inserted into the prostate to cover the desired treatment zone and subsequent activation by laser light 753 nm with a fixed power of 150 mW/cm for 22 min 15 s) or active surveillance. Randomisation was done by a web-based allocation system stratified by centre with balanced blocks of two or four patients. Best practice for active surveillance at the time of study design was followed (ie, biopsy at 12-month intervals and prostate-specific antigen measurement and digital rectal examination at 3-month intervals). The co-primary endpoints were treatment failure (histological progression of cancer from low to moderate or high risk or death during 24 months' follow-up) and absence of definite cancer (absence of any histology result definitely positive for cancer at month 24). Analysis was by intention to treat. Treatment was open-label, but investigators assessing primary efficacy outcomes were masked to treatment allocation. This trial is registered with ClinicalTrials.gov , number NCT01310894. Findings Between March 8, 2011, and April 30, 2013, we randomly assigned 206 patients to vascular-targeted photodynamic therapy and 207 patients to active surveillance. Median follow-up was 24 months (IQR 24–25). The proportion of participants who had disease progression at month 24 was 58 (28%) of 206 in the vascular-targeted photodynamic therapy group compared with 120 (58%) of 207 in the active surveillance group (adjusted hazard ratio 0·34, 95% CI 0·24–0·46; p<0·0001). 101 (49%) men in the vascular-targeted photodynamic therapy group had a negative prostate biopsy result at 24 months post treatment compared with 28 (14%) men in the active surveillance group (adjusted risk ratio 3·67, 95% CI 2·53–5·33; p<0·0001). Vascular-targeted photodynamic therapy was well tolerated. The most common grade 3–4 adverse events were prostatitis (three 2% in the vascular-targeted photodynamic therapy group vs one <1% in the active surveillance group), acute urinary retention (three 2% vs one <1%) and erectile dysfunction (two 1% vs three 1%). The most common serious adverse event in the vascular-targeted photodynamic therapy group was retention of urine (15 patients; severe in three); this event resolved within 2 months in all patients. The most common serious adverse event in the active surveillance group was myocardial infarction (three patients). Interpretation Padeliporfin vascular-targeted photodynamic therapy is a safe, effective treatment for low-risk, localised prostate cancer. This treatment might allow more men to consider a tissue-preserving approach and defer or avoid radical therapy. Funding Steba Biotech.
We have detected transient X-ray activity from the X-ray burster 4U~0614+091
simultaneously with BATSE/CGRO (20-100 keV) and ASM/RXTE (1-12 keV). The peak
fluxes reach approximately 40 mCrab in both ...instruments over a period of about
20 days. The variable emission shows a clear anticorrelation of the hard X-ray
flux with the soft X-ray count rate. The observed anticorrelation is another
clear counterexample to the notion that only black hole binaries exhibit such
correlations. The individual spectra during this period can be fit by power
laws with photon indices 2.2+-0.3 (ASM) and 2.7+-0.4 (BATSE), while the
combined spectra can be described by a single power law with index 2.09+-0.08.
BATSE and the ASM/RXTE are a good combination for monitoring X-ray sources over
a wide energy band.
The Tropospheric Ozone Assessment Report (TOAR) is an activity of the International Global Atmospheric Chemistry Project. This paper is a component of the report, focusing on the present-day ...distribution and trends of tropospheric ozone relevant to climate and global atmospheric chemistry model evaluation. Utilizing the TOAR surface ozone database, several figures present the global distribution and trends of daytime average ozone at 2702 non-urban monitoring sites, highlighting the regions and seasons of the world with the greatest ozone levels. Similarly, ozonesonde and commercial aircraft observations reveal ozone’s distribution throughout the depth of the free troposphere. Long-term surface observations are limited in their global spatial coverage, but data from remote locations indicate that ozone in the 21st century is greater than during the 1970s and 1980s. While some remote sites and many sites in the heavily polluted regions of East Asia show ozone increases since 2000, many others show decreases and there is no clear global pattern for surface ozone changes since 2000. Two new satellite products provide detailed views of ozone in the lower troposphere across East Asia and Europe, revealing the full spatial extent of the spring and summer ozone enhancements across eastern China that cannot be assessed from limited surface observations. Sufficient data are now available (ozonesondes, satellite, aircraft) across the tropics from South America eastwards to the western Pacific Ocean, to indicate a likely tropospheric column ozone increase since the 1990s. The 2014–2016 mean tropospheric ozone burden (TOB) between 60°N–60°S from five satellite products is 300 Tg ± 4%. While this agreement is excellent, the products differ in their quantification of TOB trends and further work is required to reconcile the differences. Satellites can now estimate ozone’s global long-wave radiative effect, but evaluation is difficult due to limited in situ observations where the radiative effect is greatest.
The singlet excited states of adenine oligomers, model systems widely used for the understanding of the interaction of ultraviolet radiation with DNA, are investigated by fluorescence spectroscopy ...and time‐dependent (TD) DFT calculations. Fluorescence decays, fluorescence anisotropy decays, and time‐resolved fluorescence spectra are recorded from the femtosecond to the nanosecond timescales for single strand (dA)20 in aqueous solution. These experimental observations and, in particular, the comparison of the fluorescence behavior upon UVC and UVA excitation allow the identification of various types of electronic transitions with different energy and polarization. Calculations performed for up to five stacked 9‐methyladenines, taking into account the solvent, show that different excited states are responsible for the absorption in the UVC and UVA spectral domains. Independently of the number of bases, bright excitons may evolve toward two types of excited dimers having π–π* or charge‐transfer character, each one distinguished by its own geometry and spectroscopic signature. According to the picture arising from the joint experimental and theoretical investigation, UVC‐induced fluorescence contains contribution from 1) exciton states with a different degree of localization, decaying within a few ps, 2) “neutral” excited dimers decaying on the sub‐nanosecond timescale, being the dominant species, and 3) charge‐transfer states decaying on the nanosecond timescale. The majority of the photons emitted upon UVA excitation are related to charge‐transfer states.
UVA versus UVC: Experiments and calculations show that, after absorption of ultraviolet light, the excited states of DNA adenine single strands can decay to the ground state by following different pathways. These involve mainly stacked adenine dimers and are related to either π–π* or charge‐transfer electronic transitions. The preferred decay path is largely determined by the energy of the absorbed photon (see figure).
The development of NIRF cathepsin activity probes offered the ability to visualize tumor associated tumor reaction and act as a surrogate marker to delineate the dysplastic lesions. One major type is ...a NIRF substrate of cathepsins (SBP), which is involved in catalytic way to produce high levels of fluorescence emission. The other major type (ABP) reacts with active cathepsins in stoichiometric manner since they bind covalently with their active center. Little is known about the sensitivity and the specificity of the NIRF probes to detect autochthonous developed dysplastic lesions. Dual laser NIRF endoscope provides a good tool to determine the efficiency of various NIRF probes in vivo in the same lesions.
In the current study, we validated both types of NIRF probes by using the dual laser NIRF endoscope to detect lesions colon cancer mouse model (TS4Cre/cAPC +/lox).
The dual laser NIRF endoscope is emitting equal power with both lasers. It can detect with the same efficiency in 680 mode, as well as, 750 mode when NIFR probes of the same scaffold in vivo. When SBP and ABP were used, our results showed both probes are efficient enough to detect large polyps but small dysplastic lesions could not efficiently imaged with the ABP.
The dual laser NIRF endoscope is a powerful tool to validate probes. The probes that react catalytically with the active center of cathepsins are more efficient than the ones that react stoichiometrically in detecting small lesions.
Vertebral fracture assessment (VFA) images are acquired in dual-energy (DE) or single-energy (SE) scan modes. Automated identification of vertebral compression fractures, from VFA images acquired ...using GE Healthcare scanners in DE mode, has achieved high accuracy through the use of convolutional neural networks (CNNs). Due to differences between DE and SE images, it is uncertain whether CNNs trained on one scan mode will generalize to the other.
To evaluate the ability of CNNs to generalize between GE DE and GE SE VFA scan modes.
12,742 GE VFA images from the Manitoba Bone Mineral Density Program, obtained between 2010 and 2017, were exported in both DE and SE modes. VFAs were classified by imaging specialists as fracture present or absent using the modified algorithm-based qualitative (mABQ) method. VFA scans were randomly divided into independent training (60%), validation (10%), and test (30%) sets. Three CNN models were constructed by training separately on DE only, SE only, and a composite dataset comprised of both SE and DE VFAs. All three trained CNN models were separately evaluated against both SE and DE test datasets.
Good performance was seen for CNNs trained and evaluated on the same scan mode. DE scans used for both training and evaluation (DE/DE) achieved 87.9% sensitivity, 87.4% specificity, and an area under the receiver operating characteristic curve (AUC) of 0.94. SE scans used for both training and evaluation (SE/SE) achieved 78.6% sensitivity, 90.6% specificity, AUC = 0.92. Conversely, CNNs performed poorly when evaluated on scan modes that differed from their training sets (AUC = 0.58). However, a composite CNN trained simultaneously on both SE and DE VFAs gave performance comparable to DE/DE (82.4% sensitivity, 94.3% specificity, AUC = 0.95); and provided improved performance over SE/SE (82.2% sensitivity, 92.3% specificity, AUC = 0.94). Positive predictive value was higher with the composite CNN compared with models trained solely on DE (74.5% vs. 58.7%) or SE VFAs (68.6% vs. 62.9%).
CNNs for vertebral fracture identification are highly sensitive to scan mode. Training CNNs on a composite dataset, comprised of both GE DE and GE SE VFAs, allows CNNs to generalize to both scan modes and may facilitate the development of manufacturer-independent machine learning models for vertebral fracture detection.
•DXA vertebral fracture assessment (VFA) scans can be acquired in both dual- and single-energy modes.•Convolutional neural networks can accurately detect vertebral fractures in VFA scans.•Training machine learning models simultaneously on dual- and single-energy VFAs improves fracture recognition.•Convolutional neural networks can learn to generalize to both dual- and single-energy VFA scan modes.
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