Low-Cost, High-Resolution and High-Sensitivity PET Detector Modules

PET detector modules using CsI(Na), wavelength-shifting fiber readout, and single-photon counting electronic

A Scintillating Fiber Hodoscope for a Bremstrahlung Luminosity Monitor at an Electron−-Positron Collider

The performance of a scintillating fiber (2mm diameter) position sensitive detector ($4.8 \times 4.8$ cm$^2$ active area) for the single bremstrahlung luminosity monitor at the VEPP-2M electron-positron collider in Novosibirsk, Russia is described. Custom electronics is triggered by coincident hits in the X and Y planes of 24 fibers each, and reduces 64 PMT signals to a 10 bit (X,Y) address. Hits are accumulated (10 kHz) in memory and display (few Hz) the VEPP-2M collision vertex. Fitting the strongly peaked distribution ( $\sim$ 3-4 mm at 1.6m from the collision vertex of VEPP-2M ) to the expected QED angular distribution yields a background in agreement with an independent determination of the VEPP-2M luminosity.Comment: LaTeX with REVTeX style and options: multicol,aps. 8 pages, postscript figures separate from text. Accepted in Review of Scientific Instruments (~ Aug 1996

The Lowest Order Hadronic Contribution to the Muon g−2g-2 Value with Systematic Error Correlations

We have performed a new evaluation of the hadronic contribution to $a_{\mu}=(g-2)/2$ of the muon with explicit correlations of systematic errors among the experimental data on $\sigma( e^+e^- \to hadrons )$. Our result for the lowest order hadronic vacuum polarization contribution is $a_{\mu}^{had} = 702.6(7.8)(14.0) \times 10^{-10}$ where the the first error is statistical and the second is systematic. The total systematic error contributions from below and above $\sqrt{s} = 1.4$ GeV are $(13.1) \times 10^{-10}$ and $(5.1) \times 10^{-10}$ respectively, and are hence dominated by the low energy region. Therefore, new measurements on $\sigma( e^+e^- \to hadrons )$ below 1.4 GeV can significantly reduce the total error on $a_{\mu}^{had}$. In particular, the effect on the total errors of new hypothetical data with 3 \% statistical and 0.5 - 1.0 \% systematic errors is presented.Comment: LaTeX with REVTeX style and options: multicol,aps,psfig. 18 pages, postscript figures included after text. Accepted in Phys. Rev. D (~ Sept 1996

SEARCH FOR SLOWLY MOVING MAGNETIC MONOPOLES WITH THE MACRO DETECTOR

A search for slowly moving magnetic monopoles in the cosmic radiation was conducted from October 1989 to November 1991 using the large liquid scintillator detector subsystem of the first supermodule of the MACRO detector at the Gran Sasso underground laboratory. The absence of candidates established an upper limit on the monopole flux of 5.6 x 10(-15) cm-2 sr-1 s-1 at 90% confidence level in the velocity range of 10(-4) less than or similar to beta < 4 x 10(-3). This result places a new constraint on the abundance of monopoles trapped in our solar system

Machine learning based CRISPR gRNA design for therapeutic exon skipping

© 2021 Louie et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Restoring gene function by the induced skipping of deleterious exons has been shown to be effective for treating genetic disorders. However, many of the clinically successful therapies for exon skipping are transient oligonucleotide-based treatments that require frequent dosing. CRISPR-Cas9 based genome editing that causes exon skipping is a promising therapeutic modality that may offer permanent alleviation of genetic disease. We show that machine learning can select Cas9 guide RNAs that disrupt splice acceptors and cause the skipping of targeted exons. We experimentally measured the exon skipping frequencies of a diverse genome-integrated library of 791 splice sequences targeted by 1,063 guide RNAs in mouse embryonic stem cells. We found that our method, SkipGuide, is able to identify effective guide RNAs with a precision of 0.68 (50% threshold predicted exon skipping frequency) and 0.93 (70% threshold predicted exon skipping frequency). We anticipate that SkipGuide will be useful for selecting guide RNA candidates for evaluation of CRISPR-Cas9-mediated exon skipping therapy