109 research outputs found
Low loss CMOS-compatible PECVD silicon nitride waveguides and grating couplers for blue light optogenetic applications
This paper presents silicon nitride (SixNy) photonic integrated circuits (PICs) with high performance at a wavelength of 450 nm, which, therefore, is suitable for neuronal stimulation with optogenetics. These PICs consist of straight and bent waveguides, and grating couplers that are fabricated in a complementary metal-oxide-semiconductor (CMOS)-compatible plasma enhanced chemical vapor deposition SixNy platform. Their characterization shows propagation losses of 0.96 +/- 0.4 dB/cm on average for straight waveguides that are 1-5 mu m wide and bend insertion losses as low as 0.2 dB/90. for 1 mu m wide waveguides with a radius of 100 mu m. Additionally, the grating coupler characterization shows that they can deliver about 10 mu W of light in an area of 5 x 9 mu m(2) (240 mW/mm(2)), which is captured from an uncollimated laser diode (70 mW). Besides delivering sufficient power for optogenetic applications, the gratings have dimensions that are comparable to the size of a neuron, which would allow single cell interaction. These results demonstrate that, with this SixNy platform, high-density and large-scale implantable neural devices can be fabricated and readily integrated into existing CMOS-compatible neuro-electronic platforms
Evaluation of WGS performance for bacterial pathogen characterization with the Illumina technology optimized for time-critical situations
Whole genome sequencing (WGS) has become the reference standard for bacterial outbreak investigation and pathogen
typing, providing a resolution unattainable with conventional molecular methods. Data generated with Illumina sequencers can
however only be analysed after the sequencing run has finished, thereby losing valuable time during emergency situations. We
evaluated both the effect of decreasing overall run time, and also a protocol to transfer and convert intermediary files generated
by Illumina sequencers enabling real-time
data analysis for multiple samples part of the same ongoing sequencing run,
as soon as the forward reads have been sequenced. To facilitate implementation for laboratories operating under strict quality
systems, extensive validation of several bioinformatics assays (16S rRNA species confirmation, gene detection against virulence
factor and antimicrobial resistance databases, SNP-based
antimicrobial resistance detection, serotype determination,
and core genome multilocus sequence typing) for three bacterial pathogens (Mycobacterium tuberculosis, Neisseria meningitidis,
and Shiga-toxin
producing Escherichia coli) was performed by evaluating performance in function of the two most critical
sequencing parameters, i.e. read length and coverage. For the majority of evaluated bioinformatics assays, actionable results
could be obtained between 14 and 22 h of sequencing, decreasing the overall sequencing-to-
results
time by more than half.
This study aids in reducing the turn-around
time of WGS analysis by facilitating a faster response in time-critical
scenarios and
provides recommendations for time-optimized
WGS with respect to required read length and coverage to achieve a minimum
level of performance for the considered bioinformatics assay(s), which can also be used to maximize the cost-effectiveness
of
routine surveillance sequencing when response time is not essential.The Belgian Federal Public Service of Health, Food Chain Safety and Environment and Sciensano RP-PJ - Belgium.https://www.microbiologyresearch.org/content/journal/mgenam2022Genetic
Frequency of KCNC3 DNA Variants as Causes of Spinocerebellar Ataxia 13 (SCA13)
Gain-of function or dominant-negative mutations in the voltage-gated potassium channel KCNC3 (Kv3.3) were recently identified as a cause of autosomal dominant spinocerebellar ataxia. Our objective was to describe the frequency of mutations associated with KCNC3 in a large cohort of index patients with sporadic or familial ataxia presenting to three US ataxia clinics at academic medical centers.DNA sequence analysis of the coding region of the KCNC3 gene was performed in 327 index cases with ataxia. Analysis of channel function was performed by expression of DNA variants in Xenopus oocytes.Sequence analysis revealed two non-synonymous substitutions in exon 2 and five intronic changes, which were not predicted to alter splicing. We identified another pedigree with the p.Arg423His mutation in the highly conserved S4 domain of this channel. This family had an early-onset of disease and associated seizures in one individual. The second coding change, p.Gly263Asp, subtly altered biophysical properties of the channel, but was unlikely to be disease-associated as it occurred in an individual with an expansion of the CAG repeat in the CACNA1A calcium channel.Mutations in KCNC3 are a rare cause of spinocerebellar ataxia with a frequency of less than 1%. The p.Arg423His mutation is recurrent in different populations and associated with early onset. In contrast to previous p.Arg423His mutation carriers, we now observed seizures and mild mental retardation in one individual. This study confirms the wide phenotypic spectrum in SCA13
The genomic landscape of balanced cytogenetic abnormalities associated with human congenital anomalies
Despite the clinical significance of balanced chromosomal abnormalities (BCAs), their characterization has largely been restricted to cytogenetic resolution. We explored the landscape of BCAs at nucleotide resolution in 273 subjects with a spectrum of congenital anomalies. Whole-genome sequencing revised 93% of karyotypes and demonstrated complexity that was cryptic to karyotyping in 21% of BCAs, highlighting the limitations of conventional cytogenetic approaches. At least 33.9% of BCAs resulted in gene disruption that likely contributed to the developmental phenotype, 5.2% were associated with pathogenic genomic imbalances, and 7.3% disrupted topologically associated domains (TADs) encompassing known syndromic loci. Remarkably, BCA breakpoints in eight subjects altered a single TAD encompassing MEF2C, a known driver of 5q14.3 microdeletion syndrome, resulting in decreased MEF2C expression. We propose that sequence-level resolution dramatically improves prediction of clinical outcomes for balanced rearrangements and provides insight into new pathogenic mechanisms, such as altered regulation due to changes in chromosome topology
Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015
Forouzanfar MH, Afshin A, Alexander LT, et al. Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015. LANCET. 2016;388(10053):1659-1724.Background The Global Burden of Diseases, Injuries, and Risk Factors Study 2015 provides an up-to-date synthesis of the evidence for risk factor exposure and the attributable burden of disease. By providing national and subnational assessments spanning the past 25 years, this study can inform debates on the importance of addressing risks in context. Methods We used the comparative risk assessment framework developed for previous iterations of the Global Burden of Disease Study to estimate attributable deaths, disability-adjusted life-years (DALYs), and trends in exposure by age group, sex, year, and geography for 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks from 1990 to 2015. This study included 388 risk-outcome pairs that met World Cancer Research Fund-defined criteria for convincing or probable evidence. We extracted relative risk and exposure estimates from randomised controlled trials, cohorts, pooled cohorts, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. We developed a metric that allows comparisons of exposure across risk factors-the summary exposure value. Using the counterfactual scenario of theoretical minimum risk level, we estimated the portion of deaths and DALYs that could be attributed to a given risk. We decomposed trends in attributable burden into contributions from population growth, population age structure, risk exposure, and risk-deleted cause-specific DALY rates. We characterised risk exposure in relation to a Socio-demographic Index (SDI). Findings Between 1990 and 2015, global exposure to unsafe sanitation, household air pollution, childhood underweight, childhood stunting, and smoking each decreased by more than 25%. Global exposure for several occupational risks, high body-mass index (BMI), and drug use increased by more than 25% over the same period. All risks jointly evaluated in 2015 accounted for 57.8% (95% CI 56.6-58.8) of global deaths and 41.2% (39.8-42.8) of DALYs. In 2015, the ten largest contributors to global DALYs among Level 3 risks were high systolic blood pressure (211.8 million [192.7 million to 231.1 million] global DALYs), smoking (148.6 million [134.2 million to 163.1 million]), high fasting plasma glucose (143.1 million [125.1 million to 163.5 million]), high BMI (120.1 million [83.8 million to 158.4 million]), childhood undernutrition (113.3 million [103.9 million to 123.4 million]), ambient particulate matter (103.1 million [90.8 million to 115.1 million]), high total cholesterol (88.7 million [74.6 million to 105.7 million]), household air pollution (85.6 million [66.7 million to 106.1 million]), alcohol use (85.0 million [77.2 million to 93.0 million]), and diets high in sodium (83.0 million [49.3 million to 127.5 million]). From 1990 to 2015, attributable DALYs declined for micronutrient deficiencies, childhood undernutrition, unsafe sanitation and water, and household air pollution; reductions in risk-deleted DALY rates rather than reductions in exposure drove these declines. Rising exposure contributed to notable increases in attributable DALYs from high BMI, high fasting plasma glucose, occupational carcinogens, and drug use. Environmental risks and childhood undernutrition declined steadily with SDI; low physical activity, high BMI, and high fasting plasma glucose increased with SDI. In 119 countries, metabolic risks, such as high BMI and fasting plasma glucose, contributed the most attributable DALYs in 2015. Regionally, smoking still ranked among the leading five risk factors for attributable DALYs in 109 countries; childhood underweight and unsafe sex remained primary drivers of early death and disability in much of sub-Saharan Africa. Interpretation Declines in some key environmental risks have contributed to declines in critical infectious diseases. Some risks appear to be invariant to SDI. Increasing risks, including high BMI, high fasting plasma glucose, drug use, and some occupational exposures, contribute to rising burden from some conditions, but also provide opportunities for intervention. Some highly preventable risks, such as smoking, remain major causes of attributable DALYs, even as exposure is declining. Public policy makers need to pay attention to the risks that are increasingly major contributors to global burden. Copyright (C) The Author(s). Published by Elsevier Ltd
Decision Support Tools for the Collaborative Trajectory Options Program
The FAA currently makes frequent use of Flow Constrained Areas (FCAs) to thin traffic through some region of airspace by assigning departure delay to flights filed to fly through that airspace. An important potential future use of such FCAs is their integrated application within a Collaborative Trajectory Options Program (CTOP) Traffic Management Initiative (TMI). This paper reports the results of cognitive walkthroughs completed with ten recently retired traffic managers. These walkthroughs were designed to evaluate information and information display requirements, as well as other decision support requirements, for software to enable the creation of FCAs for a CTOP TM
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