Fragment distribution in
                    78,86
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                    Ta reactions

Traditional fragmentation warheads are usually initiated on the axis, producing a uniform fragment distribution around the warhead, but only little portion of them can be imposed on the targets. The aimable warhead, on the other hand, using the off-axis initiations or the structure deforming, can improve the warhead energy utilization highly. Seeking methods to both enhance the fragment velocity and density has significant value for improving the target damage probability. In this article, a warhead shaped as hexagonal prism was studied using arena experiment and numerical modeling and compared with the traditional cylindrical structure. The fragment velocities and target hit patterns of the two types of warheads under axial initiation and asymmetrical initiation are obtained. It is revealed that for the hexagonal prism warhead, the asymmetrical initiation can enhance the fragment velocities by 27.71% and enhance fragment density by 34.09% compared to the axial initiation. The fragment velocity enhancement is close to that of the cylindrical warhead, but the fragment density enhancement is far above the cylindrical warhead. This indicates that the asymmetrically initiated hexagonal prism warhead is a very effective aimable warhead.

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Fragment distribution of thermal decomposition for lignin monomer by QMD calculations using the excited and charged model molecules

Applied Surface Science ◽

10.1016/j.apsusc.2008.05.277 ◽

2008 ◽

Vol 255 (4) ◽

pp. 1048-1051 ◽

Cited By ~ 2

Author(s):

Kazunaka Endo ◽

Daisuke Matsumoto ◽

Kenichi Kato ◽

Yusuke Takagi ◽

Tomonori Ida ◽

...

Keyword(s):

Thermal Decomposition ◽

Fragment Distribution ◽

Charged Model

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Mixture models reveal multiple positional bias types in RNA-Seq data and lead to accurate transcript concentration estimates

10.1101/011767 ◽

2014 ◽

Author(s):

Andreas Tuerk ◽

Gregor Wiktorin ◽

Serhat Güler

Keyword(s):

Probability Distributions ◽

False Positive Rate ◽

Synthetic Data ◽

True Positive Rate ◽

Rna Seq ◽

Microarray Quality Control ◽

Data Set ◽

Rna Transcripts ◽

Positive Rate ◽

Fragment Distribution

Quantification of RNA transcripts with RNA-Seq is inaccurate due to positional fragment bias, which is not represented appropriately by current statistical models of RNA-Seq data. This article introduces the Mix2(rd. "mixquare") model, which uses a mixture of probability distributions to model the transcript specific positional fragment bias. The parameters of the Mix2model can be efficiently trained with the Expectation Maximization (EM) algorithm resulting in simultaneous estimates of the transcript abundances and transcript specific positional biases. Experiments are conducted on synthetic data and the Universal Human Reference (UHR) and Brain (HBR) sample from the Microarray quality control (MAQC) data set. Comparing the correlation between qPCR and FPKM values to state-of-the-art methods Cufflinks and PennSeq we obtain an increase in R2value from 0.44 to 0.6 and from 0.34 to 0.54. In the detection of differential expression between UHR and HBR the true positive rate increases from 0.44 to 0.71 at a false positive rate of 0.1. Finally, the Mix2model is used to investigate biases present in the MAQC data. This reveals 5 dominant biases which deviate from the common assumption of a uniform fragment distribution. The Mix2software is available at http://www.lexogen.com/fileadmin/uploads/bioinfo/mix2model.tgz.

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A FORMULA TO PREDICT THE TRANSMISSION FREQUENCY OF ACENTRIC FRAGMENTS

Genetics ◽

10.1093/genetics/72.4.777 ◽

1972 ◽

Vol 72 (4) ◽

pp. 777-782

Author(s):

A V Carrano

Keyword(s):

Cell Death ◽

Poisson Distribution ◽

Transmission Frequency ◽

Chromosomal Deletions ◽

Radiation Induced ◽

Fragment Distribution ◽

The Mean ◽

Th 1

ABSTRACT A formula, based on the Poisson distribution of radiation-induced chromosomal deletions, was derived to predict the frequency of transmission of acentric fragments between subsequent mitoses. The frequency of deletions observed in the i th + 1 division subsequent to fragment distribution at the i th division anaphase is independent of the cell death resulting from fragment loss. Further, the transmission frequency of chromosome acentric fragments is mathematically equal to the fragment frequency observed in the i th + 1 generation divided by the mean fragment frequency in the i th generation. The formula was also extended to chromatid deletions.

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Fragmentation of Plasmid DNA Produced by Gamma Radiation: A Theoretical Approach

ISRN Biophysics ◽

10.5402/2012/725350 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6

Author(s):

R. A. S. Silva ◽

J. D. T. Arruda-Neto ◽

L. Nieto

Keyword(s):

Plasmid Dna ◽

Fragment Size ◽

Power Laws ◽

Double Strand Breaks ◽

Strand Breaks ◽

Starting Point ◽

Dna Strands ◽

High Let ◽

Fragment Distribution ◽

Dna Strand

Breaks in DNA, resulting in fragmented parts, can be produced by ionizing radiation which, in turn, is the starting point in the search for novel physical aspects of DNA strands. Double-strand breaks in particular cause disruption of the DNA strand, splitting it into several fragments. In order to study effects produced by radiation in plasmid DNA, a new simple mechanical model for this molecule is proposed. In this model, a Morse-like potential and a high-LET component are used to describe the DNA-radiation interaction. Two power laws, used to fit results of the model, suggest that, firstly, distribution of fragment size is nonextensive and, secondly, that a transition phase is present in the DNA fragment distribution pattern.

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Sequential Dissociation Kinetics and Fragment Distribution of Cluster Ions

European Journal of Mass Spectrometry ◽

10.1255/ejms.345 ◽

2000 ◽

Vol 6 (4) ◽

pp. 325-330 ◽

Cited By ~ 1

Author(s):

Rong-Bin Huang ◽

Hong Chen ◽

Qiang Zhang ◽

Lan-Sun Zheng

Keyword(s):

Cluster Ions ◽

Dissociation Kinetics ◽

Fragment Distribution

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Statistical Mechanics of Discrete Multicomponent Fragmentation

Condensed Matter ◽

10.3390/condmat5040064 ◽

2020 ◽

Vol 5 (4) ◽

pp. 64

Author(s):

Themis Matsoukas

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Partition Function ◽

Statistical Mechanics ◽

Closed Form ◽

Fixed Number ◽

Arbitrary Degree ◽

Fragment Distribution ◽

The Mean ◽

Fragmentation Event

We formulate the statistics of the discrete multicomponent fragmentation event using a methodology borrowed from statistical mechanics. We generate the ensemble of all feasible distributions that can be formed when a single integer multicomponent mass is broken into fixed number of fragments and calculate the combinatorial multiplicity of all distributions in the set. We define random fragmentation by the condition that the probability of distribution be proportional to its multiplicity, and obtain the partition function and the mean distribution in closed form. We then introduce a functional that biases the probability of distribution to produce in a systematic manner fragment distributions that deviate to any arbitrary degree from the random case. We corroborate the results of the theory by Monte Carlo simulation, and demonstrate examples in which components in sieve cuts of the fragment distribution undergo preferential mixing or segregation relative to the parent particle.

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