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BACKGROUND: Meningiomas are the most common primary benign brain tumors in adults. Given the extended life expectancy of most meningiomas, consideration of quality of life (QOL) is important when selecting the optimal management strategy. There is currently a dearth of meningioma-specific QOL tools in the literature. OBJECTIVE: In this systematic review, we analyze the prevailing themes and propose toward building a meningioma-specific QOL assessment tool. METHODS: A systematic search was conducted, and only original studies based on adult patients were considered. QOL tools used in the various studies were analyzed for identification of prevailing themes in the qualitative analysis. The quality of the studies was also assessed. RESULTS: Sixteen articles met all inclusion criteria. Fifteen different QOL assessment tools assessed social and physical functioning, psychological, and emotional well-being. Patient perceptions and support networks had a major impact on QOL scores. Surgery negatively affected social functioning in younger patients, while radiation therapy had a variable impact. Any intervention appeared to have a greater negative impact on physical functioning compared to observation. CONCLUSION: Younger patients with meningiomas appear to be more vulnerable within social and physical functioning domains. All of these findings must be interpreted with great caution due to great clinical heterogeneity, limited generalizability, and risk of bias. For meningioma patients, the ideal QOL questionnaire would present outcomes that can be easily measured, presented, and compared across studies. Existing scales can be the foundation upon which a comprehensive, standard, and simple meningioma-specific survey can be prospectively developed and validated.
Introduction: Acute atrial fibrillation (AAF) is the most common arrhythmia managed in the Emergency Department (ED). Direct costs of AAF are primarily attributed to ED visits and subsequent admission to hospital. A better understanding of patients attitudes regarding ED attendance is necessary to develop strategies to improve the patient care experience while simultaneously reducing ED presentation and inappropriate hospital admissions. This study aims to describe patient perspectives on ED use for AAF using in-depth qualitative interviews. Methods: An interview template designed to explore why patients attend the ED for AAF was constructed based on the Theoretical Domains Framework, a theory-informed approach that utilizes 14 domains to describe influencers of behavior. We conducted audio-recorded, semi-structured interviews of patients following their presentation to the ED for management of AAF. Interviews were anonymized, transcribed and imported into NVivo for coding and analysis. Two independent reviewers used a direct approach to code participant statements. Discrepancies were resolved by a third party. Belief statements were generated and relevant domains identified based on high frequency scores, conflicting belief statements or evidence of strong influencing beliefs. Results: 12 patient interviews, mean age 63.1 years, 91.7% male, 75.0% recurrent AAF, were completed. Patients stated that they attended the ED because: 1) symptom severity; 2) they were instructed by physicians to attend the ED should their AAF recur; and 3) they were encouraged by family members to attend. Their primary goal was to have relief of their symptoms. There was no expectation of specialist consultation or admission to hospital. Even though most patients stated they were open to managing these episodes independently, they reported that they did not have the knowledge or tools to do so. Conclusion: Patients with AAF present to the ED because of their symptom burden, social influences (physician and family) and lack of other management options. This study demonstrates the need for development of patient self-management strategies which will empower patients in their disease management and may decrease future ED visits.
Whilst preterm-born individuals have an increased risk of developing attention-deficit/hyperactivity disorder (ADHD), and are reported to have ADHD-like attention and arousal impairments, direct group comparisons are scarce.
We directly compared preterm-born adolescents (n = 186) to term-born adolescents with ADHD (n = 69), and term-born controls (n = 135), aged 11–23, on cognitive-performance, event-related potential and skin conductance level (SCL) measures associated with attention and arousal. The measures are from baseline and fast-incentive conditions of a four-choice reaction time task, previously shown to discriminate between the individuals with ADHD and controls. We aimed to establish whether preterm-born adolescents show: (a) identical cognitive-neurophysiological impairments to term-born adolescents with ADHD (b) possible additional impairments, and whether (c) the observed impairments correlate with ADHD symptom scores.
The preterm group, like the term-born ADHD group, showed increased mean reaction time (MRT) and reaction time variability (RTV) in the baseline condition, and attenuated contingent negative variation (CNV) amplitude (response preparation) in the fast-incentive condition. The preterm group, only, did not show significant within-group adjustments in P3 amplitude (attention allocation) and SCL (peripheral arousal). Dimensional analyses showed that ADHD symptoms scores correlated significantly with MRT, RTV and CNV amplitude only.
We find impairments in cognition and brain function in preterm-born adolescents that are linked to increased ADHD symptoms, as well as further impairments, in lack of malleability in neurophysiological processes. Our findings indicate that such impairments extend at least to adolescence. Future studies should extend these investigations into adulthood.
7″-resolution CO (1-0) observations of M82 with the Owens Valley millimeter-wave interferometer have resolved 2 components of molecular gas in the central 1.5 arcmin of the galaxy: (1) a high plane of M82, and (2) shell-like or filamentary structures of molecular gas, with size-scale as large as 400 pc, extending most likely out of the plane of the galaxy.
Little is known about the influence of meal timing and energy consumption patterns throughout the day on glucose regulation during pregnancy. We examined the association of maternal feeding patterns with glycaemic levels among lean and overweight pregnant women. In a prospective cohort study in Singapore, maternal 24-h dietary recalls, fasting glucose (FG) and 2-h postprandial glucose (2HPPG) concentrations were measured at 26–28 weeks of gestation. Women (n 985) were classified into lean (BMI<23 kg/m2) or overweight (BMI≥23 kg/m2) groups. They were further categorised as predominantly daytime (pDT) or predominantly night-time (pNT) feeders according to consumption of greater proportion of energy content from 07.00 to 18.59 hours or from 19.00 to 06.59 hours, respectively. On stratification by weight status, lean pNT feeders were found to have higher FG than lean pDT feeders (4·36 (sd 0·38) v. 4·22 (sd 0·35) mmol/l; P=0·002); however, such differences were not observed between overweight pDT and pNT feeders (4·49 (sd 0·60) v. 4·46 (sd 0·45) mmol/l; P=0·717). Using multiple linear regression with confounder adjustment, pNT feeding was associated with higher FG in the lean group (β=0·16 mmol/l; 95 % CI 0·05, 0·26; P=0·003) but not in the overweight group (β=0·02 mmol/l; 95 % CI −0·17, 0·20; P=0·879). No significant association was found between maternal feeding pattern and 2HPPG in both the lean and the overweight groups. In conclusion, pNT feeding was associated with higher FG concentration in lean but not in overweight pregnant women, suggesting that there may be an adiposity-dependent effect of maternal feeding patterns on glucose tolerance during pregnancy.
Several narrow-line Seyfert 1 galaxies (NLS1s) have now been detected in gamma rays, providing firm evidence that at least some of this class of active galactic nuclei (AGN) produce relativistic jets. The presence of jets in NLS1s is surprising, as these sources are typified by comparatively small black hole masses and near- or super-Eddington accretion rates. This challenges the current understanding of the conditions necessary for jet production. Comparing the properties of the jets in NLS1s with those in more familiar jetted systems is thus essential to improve jet production models. We present early results from our campaign to monitor the kinematics and polarization of the parsec-scale jets in a sample of 15 NLS1s through multifrequency observations with the Very Long Baseline Array. These observations are complemented by fast-cadence 15 GHz monitoring with the Owens Valley Radio Observatory 40 m telescope and optical spectroscopic monitoring with with the 2 m class telescope at the Guillermo Haro Astrophysics Observatory in Cananea, Mexico.
We are conducting a large survey of distant clusters of galaxies using radio sources with bent jets and lobes as tracers. These radio sources are driven by AGN and achieve their bent morphologies through interaction with the surrounding gas found in clusters of galaxies. Based on low-redshift studies, these types of sources can be used to identify clusters very efficiently. We present initial results from our survey of 653 bent-double radio sources with optical hosts too faint to appear in the SDSS. The sample was observed in the infrared with Spitzer, and it has revealed ~200 distant clusters or proto-clusters in the redshift range z ~ 0.7 - 3.0. The sample of bent-doubles contains both quasars and radio galaxies enabling us to study both radiative and kinetic mode feedback in cluster and group environments at a wide range of redshifts.
Variability is one of the extreme observational properties of BL Lacertae objects. AO 0235+164 is a well studied BL Lac through the whole electro-magnetic wavebands, it is violently variable in the optical bands. In the present work, we show its optical R band photometric observations carried out during the period of Nov. 2006 to Dec. 2012 using the Ap6E CCD camera attached to the primary focus of the 70 cm meniscus telescope at Abastumani Observatory, Georgia. It shows a large variation of ΔR = 4.88 mag (14.20 - 19.08 mag) during our monitoring period. When periodicity analysis methods are adopted to its R observations from our Abastumani monitoring programme and those in the literature, the signs of some periods, P1 = 8.26 yr, P2 = 0.55 yr, P3 = 0.85 yr, P4 = 1.99 yr are found.
It is not clear whether the progressive changes in brain microstructural deficits documented in previous longitudinal magnetic resonance imaging (MRI) studies might be due to the disease process or to other factors such as medication. It is important to explore the longitudinal alterations in white-matter (WM) microstructure in antipsychotic-naive patients with first-episode schizophrenia during the very early phase of treatment when relatively ‘free’ from chronicity.
Thirty-five patients with first-episode schizophrenia and 22 healthy volunteers were recruited. High-resolution diffusion tensor imaging (DTI) was obtained from participants at baseline and after 6 weeks of treatment. A ‘difference map’ for each individual was calculated from the 6-week follow-up fractional anisotropy (FA) of DTI minus the baseline FA. Differences in Positive and Negative Syndrome Scale (PANSS) scores and Global Assessment of Functioning (GAF) scores between baseline and 6 weeks were also evaluated and expressed as a 6-week/baseline ratio.
Compared to healthy controls, there was a significant decrease in absolute FA of WM around the bilateral anterior cingulate gyrus and the right anterior corona radiata of the frontal lobe in first-episode drug-naive patients with schizophrenia following 6 weeks of treatment. Clinical symptoms improved during this period but the change in FA did not correlate with the changes in clinical symptoms or the dose of antipsychotic medication.
During the early phase of treatment, there is an acute reduction in WM FA that may be due to the effects of antipsychotic medications. However, it is not possible to entirely exclude the effects of underlying progression of illness.
Evidence shows that cognitive deficits and white matter (WM) dysconnectivity can independently be associated with clinical manifestations in schizophrenia. It is important to explore this triadic relationship in order to investigate whether the triplet could serve as potential extended endophenotypes of schizophrenia.
Diffusion tensor images and clinical performances were evaluated in 122 individuals with first-episode schizophrenia and 122 age- and gender-matched controls. In addition, 65 of 122 of the patient group and 40 of 122 controls were measured using intelligence quotient (IQ) testing.
The schizophrenia group showed lower fractional anisotropy (FA) values than controls in the right cerebral frontal lobar sub-gyral (RFSG) WM. The schizophrenia group also showed a significant positive correlation between FA in the RFSG and performance IQ (PIQ); in turn, their PIQ score showed a significant negative correlation with negative syndromes.
Overall, these findings support the hypothesis that WM deficits may be a core deficit that contributes to cognitive deficits as well as to negative symptoms.
Delta-doped boron marker layers in silicon have been used to test further the relationship between B transient enhanced diffusion (TED) and the flux of silicon interstitials released during the annealing stage following self implantation. We present new data which address a number of questions raised by the present models. We show that in our experiments bulk trapping of interstitials is significant only for low implant fluences (∼1012 cm −2). The origin of the observed diffusion-like profiles for the interstitial flux is instead found to lie in local trapping within the δ-doped layers themselves. Boron trapped in immobile clusters may be associated with Si interstitials in approximately a 1:1 ratio; nevertheless this trapping contribution alone may not entirely account for the observed gradient. We suggest that some part of the observed TED response with depth is attributable to local trapping of silicon interstitials within the boron doped layers.
Cluster ion implantation is an attractive alternative to conventional ion implantation, particularly for shallow junction formation. It is easy to obtain high-current ion beams with low equivalent energy using cluster ion beams. The implanted boron distribution in 5keV B10H14 implanted Si is markedly shallower than that in 5keV BF2 ion implanted Si. The implanted depth is less than 0.04 μm, indicating that cluster ion implantation is capable of forming shallow junctions. The sheet resistance of 3keV B10H14 implanted samples falls below 500 Ω/sq after annealing at 1000°C for 10s. Shallow implantation can be realized by a high energy cluster beam without space-charge problems in the incident beam. Defect formation, resulting from local energy deposition and multiple collisions, is unique for cluster ions. The thickness of the damaged layer formed by cluster ion bombardment increases with the size of the cluster, if implant energy and ion dose remain constant. This is one of the nonlinear “cluster effects,” which may allow some control over the implant damage distributions that accompany implanted ions, and which have been shown to have a great effect on dopant redistribution during annealing
We present a new mask design and implantation scheme, which uses one single ion implantation step of 2 MeV He ions at a dose of 7–1014 to 3–1015 He/cm2 to form channel waveguides in single crystalline KNbO3. The special processing of the photoresist mask enables the formation of channel waveguides with a trapezoidal-shaped cross section, providing for the first time simultaneous confinement of both TE and TM modes in a permanent KNbO3 channel waveguide. 2.6 mW second-harmonic blue light at 441 nm was generated in a 5.8 mm long guide for a fundamental power of approx. 200 mW.
Diffuse x-ray scattering (DXS) and computer simulation techniques were employed to investigate the defect structure produced in Si by low keV ion and MeV electron irradiations. DXS measurements were performed for keV Ga and He implants, demonstrating the ability of the technique to provide both bulk and near-surface measurements at defect concentrations of about 1000 ppm. A rigorous analysis of these results is complicated due to the complex nature of the ion damage in Si. A computer simulation framework is developed to aid in the analysis of this data. In this technique, defects are simulated and their strain fields are calculated by simply relaxing the atoms around the defect to their equilibrium positions. The diffuse scattering is then calculated from the strain field, and the results are compared to the experimental measurements. Computer simulations are presented here only for the case of electron irradiation damage and compared to published measurements.1 Application of the technique to more complicated structures is planned and should pose no serious problems in the computational framework already developed.
Brain structure appears to alter after antipsychotic administration, but it is unknown whether these alterations are associated with improvement of psychopathology in patients with schizophrenia. In this study, the authors explore this relationship.
Altogether, 66 first-episode, drug-naive patients with schizophrenia and 23 well-matched healthy controls underwent brain magnetic resonance imaging scans at baseline. All 23 healthy controls and 42 of the patients were rescanned after 6 weeks follow-up. The patients received regular antipsychotic treatment during the 6-week period and their psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS) at baseline and 6 weeks. The difference in PANSS scores between baseline and 6 weeks was expressed as a ratio of the scores at baseline – ‘PANSS reduction ratio’. A modified tensor-based morphometry procedure was applied to analyse longitudinal images. Correlations between regional volume changes, PANSS reduction ratio and antipsychotic drug dosages were explored.
Compared with healthy controls, there was a significant increase in grey-matter volume of the right putamen in patients after 6 weeks treatment. This volume change was positively correlated with a positive PANSS reduction score but not related to drug dosages.
Putaminal volume increased after 6 weeks antipsychotic treatment in first-episode schizophrenia. The increased volume was closely correlated with improved psychopathology, suggesting the putamen might be a biomarker to predict the treatment response in schizophrenia.
A new fast fabrication method entailing, two step anodization of silicon with different HF solutions was used to form a high aspect ratio silicon Field Emitter Array on n-type silicon (resistivity of 0.01cm). A Silicon oxide mask was used to define the field emitter array. The silicon substrate was pre-anodized with low current density for 1 minute in the dark and then anodized in HF:H2O:Ethanol solution. Finally, the porous silicon was removed by isotropic solution etching. The turn-on voltage of the fabricated field emitters was approximately 27V/μm when the emission current density reaches 1μA/cm2. This compares with the turn-on field of about 35V/μm on silicon tip array fabricated by using an isotropic etching solution of HNO3. We obtained field emitter arrays with good uniformity and reproducibility.
An improved method for the analysis of multi-exponential transients with high resolution has been applied to DLTS. Full-waveform fittings, using the technique of Modulating Functions, are made to digitized transients captured by a computer. This technique is described and results for both simulated data (with noise) and real data are shown. The advantages over previously published techniques in resolution, calculation speed, insensitivity to truncation error and noise are discussed. Also, how this method allows for a determination of the number of components is presented.