125 research outputs found
Quantifying nanoparticle dispersion: application of the Delaunay network for objective analysis of sample micrographs
Measuring quantitatively the nanoparticle dispersion of a composite material requires more than choosing a particular parameter and determining its correspondence to good and bad dispersion. It additionally requires anticipation of the measure’s behaviour towards imperfect experimental data, such as that which can be obtained from a limited number of samples. It should be recognised that different samples from a common parent population can give statistically different responses due to sample variation alone and a measure of the likelihood of this occurring allows a decision on the dispersion to be made. It is also important to factor into the analysis the quality of the data in the micrograph with it: (a) being incomplete because some of the particles present in the micrograph are indistinguishable or go unseen; (b) including additional responses which are false. With the use of our preferred method, this article investigates the effects on the measured dispersion quality of nanoparticles of the micrograph’s magnification settings, the role of the fraction of nanoparticles visible and the number of micrographs used. It is demonstrated that the best choice of magnification, which gives the clearest indication of dispersion type, is dependent on the type of nanoparticle structure present. Furthermore, it is found that the measured dispersion can be modified by particle loss, through the limitations of micrograph construction, and material/microscope imperfections such as cut marks and optical aberrations which could lead to the wrong conclusions being drawn. The article finishes by showing the versatility of the dispersion measure by characterising various different spatial features. <br/
Excitation Function Measurements of Proton Induced Reactions on Rhodium and Indium: Yields of 97-Ru, 96-Tc, 109-Cd, and 113-Sn
Supported by the National Science Foundation and Indiana Universit
Excitation Function Measurements of Proton Induced Reactions on Rhodium and Indium: Yields of Ru-97, Tc-96, Cd-109, and Sn-113
This work was supported by National Science Foundation Grants PHY 76-84033A01, PHY 78-22774, and Indiana Universit
Searching a bitstream in linear time for the longest substring of any given density
Given an arbitrary bitstream, we consider the problem of finding the longest
substring whose ratio of ones to zeroes equals a given value. The central
result of this paper is an algorithm that solves this problem in linear time.
The method involves (i) reformulating the problem as a constrained walk through
a sparse matrix, and then (ii) developing a data structure for this sparse
matrix that allows us to perform each step of the walk in amortised constant
time. We also give a linear time algorithm to find the longest substring whose
ratio of ones to zeroes is bounded below by a given value. Both problems have
practical relevance to cryptography and bioinformatics.Comment: 22 pages, 19 figures; v2: minor edits and enhancement
Dust masses of young disks: constraining the initial solid reservoir for planet formation
Interstellar matter and star formatio
The profile of cardiac cytochrome c oxidase (COX) expression in an accelerated cardiac-hypertrophy model
The contribution of the mitochondrial components, the main source of energy for the cardiac hypertrophic growth induced by pressure overload, is not well understood. In the present study, complete coarctation of abdominal aorta was used to induce the rapid development of cardiac hypertrophy in rats. One to two days after surgery, we observed significantly higher blood pressure and cardiac hypertrophy, which remained constantly high afterwards. We found an early increased level of cytochrome c oxidase ( COX) mRNA determined by in-situ hybridization and dot blotting assays in the hypertrophied hearts, and a drop to the baseline 20 days after surgery. Similarly, mitochondrial COX protein level and enzyme activity increased and, however, dropped even lower than baseline 20 days following surgery. In addition, in natural hypertension- induced hypertrophic hearts in genetically hypertensive rats, the COX protein was significantly lower than in normotensive rats. Taken together, the lower efficiency of mitochondrial activity in the enlarged hearts of long-term complete coarcted rats or genetically hypertensive rats could be, at least partially, the cause of hypertensive cardiac disease. Additionally, the rapid complete coarctation-induced cardiac hypertrophy was accompanied by a disproportionate COX activity increase, which was suggested to maintain the cardiac energy-producing capacity in overloaded hearts
Metabolite analysis for the comparison of irrigated and non-irrigated field grown tomato of varying genotype
Autoantibodies against type I IFNs in patients with life-threatening COVID-19
Interindividual clinical variability in the course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is vast. We report that at least 101 of 987 patients with life-threatening coronavirus disease 2019 (COVID-19) pneumonia had neutralizing immunoglobulin G (IgG) autoantibodies (auto-Abs) against interferon-w (IFN-w) (13 patients), against the 13 types of IFN-a (36), or against both (52) at the onset of critical disease; a few also had auto-Abs against the other three type I IFNs. The auto-Abs neutralize the ability of the corresponding type I IFNs to block SARS-CoV-2 infection in vitro. These auto-Abs were not found in 663 individuals with asymptomatic or mild SARS-CoV-2 infection and were present in only 4 of 1227 healthy individuals. Patients with auto-Abs were aged 25 to 87 years and 95 of the 101 were men. A B cell autoimmune phenocopy of inborn errors of type I IFN immunity accounts for life-threatening COVID-19 pneumonia in at least 2.6% of women and 12.5% of men
Mouse Chromosome 11
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46996/1/335_2004_Article_BF00648429.pd
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