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Non-tuberculous mycobacterium encephalitis is rare. Since 2013, a global outbreak of Mycobacterium chimaera infection has been attributed to point-source contamination of heater cooler units used in cardiac surgery. Disseminated M. chimaera infection has presented many unique challenges, including non-specific clinical presentations with delays in diagnosis, and a high mortality rate among predominantly immunocompetent adults. Here, we describe three patients with fatal disseminated Mycobacterium chimaera infection showing initially non-specific, progressively worsening neurocognitive decline, including confusion, delirium, depression and apathy. Autopsy revealed widespread granulomatous encephalitis of the cerebrum, brain stem and spinal cord, along with granulomatous chorioretinitis. Cerebral involvement and differentiation between mycobacterial granulomas and microangiopathic changes can be assessed best on MRI with contrast enhancement. The prognosis of M. chimaera encephalitis appears to be very poor, but might be improved by increased awareness of this new syndrome and timely antimicrobial treatment.
This presentation will enable the learner to:
1. Describe the clinical, radiological and neuropathological findings of Mycobacterium chimaera encephalitis
2. Be aware of this rare form of encephalitis, and explain its diagnosis, prognosis and management
We present a broad study of linear, clustered, noble gas puffs irradiated with the frequency doubled (527 nm) Titan laser at Lawrence Livermore National Laboratory. Pure Ar, Kr, and Xe clustered gas puffs, as well as two mixed-gas puffs consisting of KrAr and XeKrAr gases, make up the targets. Characterization experiments to determine gas-puff density show that varying the experimental parameter gas-delay timing (the delay between gas puff initialization and laser-gas-puff interaction) provides a simple control over the gas-puff density. X-ray emission (>1.4 keV) is studied as a function of gas composition, density, and delay timing. Xe gas puffs produce the strongest peak radiation in the several keV spectral region. The emitted radiation was found to be anisotropic, with smaller X-ray flux observed in the direction perpendicular to both laser beam propagation and polarization directions. The degree of anisotropy is independent of gas target type but increases with photon energy. X-ray spectroscopic measurements estimate plasma parameters and highlight their difference with previous studies. Electron beams with energy in excess of 72 keV are present in the noble gas-puff plasmas and results indicate that Ar plays a key role in their production. A drastic increase in harder X-ray emissions (X-ray flash effect) and multi-MeV electron-beam generation from Xe gas-puff plasma occurred when the laser beam was focused on the front edge of the linear gas puff.
The Square Kilometre Array will be an amazing instrument for pulsar astronomy. While the full SKA will be sensitive enough to detect all pulsars in the Galaxy visible from Earth, already with SKA1, pulsar searches will discover enough pulsars to increase the currently known population by a factor of four, no doubt including a range of amazing unknown sources. Real time processing is needed to deal with the 60 PB of pulsar search data collected per day, using a signal processing pipeline required to perform more than 10 POps. Here we present the suggested design of the pulsar search engine for the SKA and discuss challenges and solutions to the pulsar search venture.
School attendance rates in sub-Saharan Africa are among the lowest worldwide, placing children at heightened risk for poor educational and economic outcomes. One understudied risk factor for missed schooling is household water insecurity, which is linked to depression among women and may increase children's water-fetching burden at the expense of educational activities, particularly among children of depressed caregivers. In this study conducted in rural Uganda, we assessed the association between household water insecurity and child school participation and the mediating pathways behind these associations.
We conducted a population-based, cross-sectional study of female household heads (N = 257) and their children ages 5–17 (N = 551) in the rural regions surrounding the town of Mbarara, in southwestern Uganda. We used multivariable linear regressions to estimate the association between water insecurity and missed schooling. We then assessed the extent to which the association was mediated by caregiver depression.
Among children, water insecurity had a statistically significant association with the number of missed school days (a standard deviation increase in water insecurity resulted in 0.30 more missed school days in the last week). The estimated association was partially mediated by caregiver depression. When stratified by sex, this mediating pathway remained significant for boys, but not among girls.
Water insecurity is a risk factor for missed schooling among children in rural Uganda. Caregiver depression partially mediated this relationship. Also addressing caregiver mental health in water insecure families may more fully address the needs of sub-Saharan African families and promote educational participation among youth.
CHD is frequently associated with a genetic syndrome. These syndromes often present specific cardiovascular and non-cardiovascular co-morbidities that confer significant peri-operative risks affecting multiple organ systems. Although surgical outcomes have improved over time, these co-morbidities continue to contribute substantially to poor peri-operative mortality and morbidity outcomes. Peri-operative morbidity may have long-standing ramifications on neurodevelopment and overall health. Recognising the cardiovascular and non-cardiovascular risks associated with specific syndromic diagnoses will facilitate expectant management, early detection of clinical problems, and improved outcomes – for example, the development of syndrome-based protocols for peri-operative evaluation and prophylactic actions may improve outcomes for the more frequently encountered syndromes such as 22q11 deletion syndrome.
Background: Deficiencies in design and reporting of randomized controlled trials (RCTs) limit their validity. The quality of recent RCTs in neurosurgery was analyzed to assess adequacy of design and reporting. Methods: A high-yield search of the MEDLINE and EMBASE databases (2000-present) was conducted. The CONSORT and Jadad scales were used to assess the quality of design/reporting. A PRECIS-based scale was used to designate studies on the pragmatic-explanatory continuum. Spearman’s test was used to assess correlations. Regression analysis was used to assess associations. Results: Sixty-one articles were identified. Vascular was the most common sub-specialty (37%). The median CONSORT and Jadad scores were 36 (IQR 27.5-39) and 3 (IQR 2-3). Blinding, sample size calculation and allocation concealment were most deficiently reported. The quality of reporting did not correlate with the study impact. The majority of studies (83%) had pragmatic objectives; while pragmatic studies had compatible design factors, trials with explanatory objectives were less successful. Conclusions: The prevalence and quality of neurosurgical RCTs is low. Many study designs are not compatible with stated objectives. Given the role of RCTs as one of the highest levels of evidence, it is critical to improve on their methodology and reporting. Alternative methodologies merit discussion.
Background: Deficiencies in design and reporting of randomized controlled trials (RCTs) limit their validity. The quality of recent RCTs in neuro-oncology was analyzed to assess adequacy of design and reporting. Methods: The MEDLINE and EMBASE databases were searched to identify non-surgical RCTs (years 2000-2010). The CONSORT and Jadad scales were used to assess the quality of design/reporting. A PRECIS-based scale was used to designate studies on the pragmatic-explanatory continuum. Spearman’s test was used to assess correlations. Regression analysis was used to assess associations. Results: Overall, 44 RCTs were identified; majority (23 studies) were chemotherapy-based. High grade gliomas (43%) and metastases (41%) were top pathologies. The majority of studies were multi-center (70%), ITT (61%), and did not collaborate with biostatisticians (70%). Half of the studies were funded by industry (50%). The median CONSORT and Jadad scores were similar in radiation and chemotherapy-based trials (34 and 35 vs 3 and 2, respectively). The impact factor was significantly associated with higher quality (p<0.01). Multi-center trials were more likely to result in positive outcomes (p = 0.02). Conclusion: Deficiencies in the quality of design and reporting of RCTs in neuro-oncology persist. Quality improvement is necessary. In parallel, alternative strategies may be required.
For the purpose of development of highly energy-efficient light sources, one needs to design highly efficient green, red and yellow phosphors, which are able to absorb excitation energy and generate emissions. In this contribution, we present our results on producing some efficient phosphors with improved luminescence properties. The effects of zinc on the zinc-doped CaTiO3:Eu3+ phosphors have been investigated by varying the zinc concentrations. X-ray powder diffraction (XRD) and Scanning electron microscopy (SEM) characterizations were studies for their structural and morphological analysis. The variation of zinc concentration influences the crystallinity and morphology of the phosphors. The luminescence spectra of (Zn,Ca)TiO3: Eu3+ have been measured. Eu3+: (Zn,Ca)TiO3 have shown five emission transitions of 5D0→7F 0,1,2,3 & 4 located at 580 nm,593nm 615 nm,655 and 704 respectively with excitation at λexci=398nm (7F0→5L6). Moreover, the emitting phosphor developed in this study can be very effectively excited at the wavelengths of 398 nm. The (Zn, Ca)TiO3:Eu3+ can be used as a complementary phosphor in there red region for the white LEDs.
A large area nanogap electrode fabrication method combinig conventional lithography patterning with the of focused ion beam (FIB) is presented. Lithography and a lift-off process were used to pattern 50 nm thick platinum pads having an area of 300 μm × 300 μm. A range of 30-300 nm wide nanogaps (length from 300 μm to 10 mm ) were then etched using an FIB of Ga+ at an acceleration voltage of 30 kV at various beam currents. An investigation of Ga+ beam current ranging between 1-50 pA was undertaken to optimise the process for the current fabrication method. In this study, we used Monte Carlo simulation to calculate the damage depth in various materials by the Ga+. Calculation of the recoil cascades of the substrate atoms are also presented. The nanogap electrodes fabricated in this study were found to have empty gap resistances exceeding several hundred MΩ. A comparison of the gap length versus electrical resistance on glass substrates is presented. The results thus outline some important issues in low-conductance measurements. The proposed nanogap fabrication method can be extended to various sensor applications, such as chemical sensing, that employ the nanogap platform. This method may be used as a prototype technique for large-scale fabrication due to its simple, fast and reliable features.