3,839 research outputs found
Biophotonic Tools in Cell and Tissue Diagnostics.
In order to maintain the rapid advance of biophotonics in the U.S. and enhance our competitiveness worldwide, key measurement tools must be in place. As part of a wide-reaching effort to improve the U.S. technology base, the National Institute of Standards and Technology sponsored a workshop titled "Biophotonic tools for cell and tissue diagnostics." The workshop focused on diagnostic techniques involving the interaction between biological systems and photons. Through invited presentations by industry representatives and panel discussion, near- and far-term measurement needs were evaluated. As a result of this workshop, this document has been prepared on the measurement tools needed for biophotonic cell and tissue diagnostics. This will become a part of the larger measurement road-mapping effort to be presented to the Nation as an assessment of the U.S. Measurement System. The information will be used to highlight measurement needs to the community and to facilitate solutions
Shaping bursting by electrical coupling and noise
Gap-junctional coupling is an important way of communication between neurons
and other excitable cells. Strong electrical coupling synchronizes activity
across cell ensembles. Surprisingly, in the presence of noise synchronous
oscillations generated by an electrically coupled network may differ
qualitatively from the oscillations produced by uncoupled individual cells
forming the network. A prominent example of such behavior is the synchronized
bursting in islets of Langerhans formed by pancreatic \beta-cells, which in
isolation are known to exhibit irregular spiking. At the heart of this
intriguing phenomenon lies denoising, a remarkable ability of electrical
coupling to diminish the effects of noise acting on individual cells.
In this paper, we derive quantitative estimates characterizing denoising in
electrically coupled networks of conductance-based models of square wave
bursting cells. Our analysis reveals the interplay of the intrinsic properties
of the individual cells and network topology and their respective contributions
to this important effect. In particular, we show that networks on graphs with
large algebraic connectivity or small total effective resistance are better
equipped for implementing denoising. As a by-product of the analysis of
denoising, we analytically estimate the rate with which trajectories converge
to the synchronization subspace and the stability of the latter to random
perturbations. These estimates reveal the role of the network topology in
synchronization. The analysis is complemented by numerical simulations of
electrically coupled conductance-based networks. Taken together, these results
explain the mechanisms underlying synchronization and denoising in an important
class of biological models
Secure optical communication using symbol-by-symbol time-domain spectral phase encoding with QPSK modulation
© Asia Communications and Photonics Conference (ACP) OSA 2019 We report the experimental demonstration of a secure optical communication system using 40 Gbps coherent quadrature phase shift keying modulation. The security is implemented in physical layer using symbol-by-symbol time domain spectral phase encoding.EPSRC Quantum Technology Hub in Quantum Communications
(reference EP/M013472/1)
Hospital admissions for vitamin D related conditions and subsequent immune-mediated disease: record-linkage studies
PMCID: PMC3729414The electronic version of this article is the complete one and can be found online at: http://www.biomedcentral.com/1741-7015/11/171.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
Cercosporoid leaf pathogens from whorled milkweed and spineless safflower in California
Two cercosporoid species are respectively described from Mexican whorled milkweed (Asclepias fascicularis), and spineless safflower (Carthamus tinctorius) from California. Passalora californica represents a new pathogen on Asclepias fascicularis, while Ramularia cynarae is confirmed on Carthamus tinctorius and Cynara cardunculus (Asteraceae), and an epitype designated. Pathogenicity is also established for both pathogens based on Koch’s postulate
Pseudovirgaria, a fungicolous hyphomycete genus
The genus Pseudovirgaria, based on P. hyperparasitica, was recently introduced for a mycoparasite of rust sori of various species of Frommeëlla, Pucciniastrum and Phragmidium in Korea. In the present study, an older name introduced by Saccardo based on European material, Rhinotrichum griseum, is shown to resemble P. hyperparasitica. Morphological study and ITS barcodes from fresh collections of R. griseum from Austria on uredinia and telia of Phragmidium bulbosum on Rubus spp. reveal that it is distinct from P. hyperparasitica. The status of the genus Rhinotrichum, introduced for a fungus occurring on dry wood, remains unclear. Pseudovirgaria grisea comb. nov. is therefore proposed for the mycoparasite occurring on rust fungi in Europe, and an epitype is designated from the recent collections
Evidence of Autoimmune-Related Effects of Trichloroethylene Exposure from Studies in Mice and Humans
Agreement between an online dietary assessment tool (myfood24) and an interviewer-administered 24-h dietary recall in British adolescents aged 11–18 years
myfood24 Is an online 24-h dietary assessment tool developed for use among British adolescents and adults. Limited information is available regarding the validity of using new technology in assessing nutritional intake among adolescents. Thus, a relative validation of myfood24 against a face-to-face interviewer-administered 24-h multiple-pass recall (MPR) was conducted among seventy-five British adolescents aged 11–18 years. Participants were asked to complete myfood24 and an interviewer-administered MPR on the same day for 2 non-consecutive days at school. Total energy intake (EI) and nutrients recorded by the two methods were compared using intraclass correlation coefficients (ICC), Bland–Altman plots (using between and within-individual information) and weighted κ to assess the agreement. Energy, macronutrients and other reported nutrients from myfood24 demonstrated strong agreement with the interview MPR data, and ICC ranged from 0·46 for Na to 0·88 for EI. There was no significant bias between the two methods for EI, macronutrients and most reported nutrients. The mean difference between myfood24 and the interviewer-administered MPR for EI was −230 kJ (−55 kcal) (95 % CI −490, 30 kJ (−117, 7 kcal); P=0·4) with limits of agreement ranging between 39 % (3336 kJ (−797 kcal)) lower and 34 % (2874 kJ (687 kcal)) higher than the interviewer-administered MPR. There was good agreement in terms of classifying adolescents into tertiles of EI (κ w =0·64). The agreement between day 1 and day 2 was as good for myfood24 as for the interviewer-administered MPR, reflecting the reliability of myfood24. myfood24 Has the potential to collect dietary data of comparable quality with that of an interviewer-administered MPR
Negative Effects of Paternal Age on Children's Neurocognitive Outcomes Can Be Explained by Maternal Education and Number of Siblings
Background: Recent findings suggest advanced paternal age may be associated with impaired child outcomes, in particular, neurocognitive skills. Such patterns are worrisome given relatively universal trends in advanced countries toward delayed nuptiality and fertility. But nature and nurture are both important for child outcomes, and it is important to control for both when drawing inferences about either pathway. Methods and Findings: We examined cross-sectional patterns in six developmental outcome measures among children in the U.S. Collaborative Perinatal Project (n = 31,346). Many of these outcomes at 8 mo, 4 y, and 7 y of age (Bayley scales, Stanford Binet Intelligence Scale, Graham-Ernhart Block Sort Test, Wechsler Intelligence Scale for Children, Wide Range Achievement Test) are negatively correlated with paternal age when important family characteristics such as maternal education and number of siblings are not included as covariates. But controlling for family characteristics in general and mother’s education in particular renders the effect of paternal age statistically insignificant for most developmental measures. Conclusions: Assortative mating produces interesting relationships between maternal and paternal characteristics that can inject spurious correlation into observational studies via omitted variable bias. Controlling for both nature and nurture reveals little residual evidence of a link between child neurocognitive outcomes and paternal age in these data. Result
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