Spin Decomposition of Electron in QED

We perform a systematic study on the spin decomposition of an electron in QED at one-loop order. It is found that the electron orbital angular momentum defined in Jaffe-Manohar and Ji spin sum rules agrees with each other, and the so-called potential angular momentum vanishes at this order. The calculations are performed in both dimensional regularization and Pauli-Villars regularization for the ultraviolet divergences, and they lead to consistent results. We further investigate the calculations in terms of light-front wave functions, and find a missing contribution from the instantaneous interaction in light-front quantization. This clarifies the confusing issues raised recently in the literature on the spin decomposition of an electron, and will help to consolidate the spin physics program for nucleons in QCD.Comment: 8 page

A multichannel thiacalix[4]arene-based fluorescent chemosensor for Zn²⁺, F⁻ ions and imaging of living cells

The fluorescent sensor (3) based on the 1,3-alternate conformation of the thiacalix[4]arene bearing the coumarin fluorophore, appended via an imino group, has been synthesised. Sensing properties were evaluated in terms of a colorimetric and fluorescence sensor for Zn 2+ and F - . High selectivity and excellent sensitivity were exhibited, and off-on optical behaviour in different media was observed. All changes were visible to the naked eye, whilst the presence of the Zn 2+ and F - induces fluorescence enhancement and the formation of a 1:1 complex with 3. In addition, 3 exhibits low cytotoxicity and good cell permeability and can readily be employed for assessing the change of intracellular levels of Zn 2+ and F -

A Characterization of E

A class of vector optimization problems is considered and a characterization of E-Benson proper efficiency is obtained by using a nonlinear scalarization function proposed by Göpfert et al. Some examples are given to illustrate the main results

A single chemosensor for multiple analytes: fluorogenic and ratiometric absorbance detection of Zn²⁺, Mg²⁺ and F⁻, and its cell imaging

A simple coumarin based sensor 1 has been synthesized from the condensation reaction of 7-hydroxycoumarin and ethylenediamine via the intermediate 7-hydroxy-8-aldehyde-coumarin. As a multiple analysis sensor, 1 can monitor Zn²⁺ with the fluorescence enhanced at 457 nm, and ratiometric detection at 290 nm, 350 nm and 420 nm in DMF/H₂O (1/4, v/v) medium. Sensor 1 can also monitor Mg²⁺ with the fluorescence enhanced at 430 nm, and ratiometric detection at 290 nm, 370 nm and 430 nm in DMF medium through the interaction of chelation enhance fluorescence (CHEF) with metal ions. Furthermore, 1 also can monitor F⁻ with the fluorescence enhanced at 460 nm, and ratiometric detection at 290 nm and 390 nm in DMF medium simultaneously via hydrogen bonding and deprotonation with F− anion. Spectral titration, isothermal titration calorimetry and mass spectrometry revealed that the sensor formed a 1:1 complex with Mg²⁺, Zn²⁺ or F⁻, with stability constants of 4.5 × 10⁶, 3.4 × 10⁶, 8.0 × 10⁴ M⁻1 respectively. The complexation of the ions by 1 was an exothermic reaction driven by entropy processes. Furthermore, the sensor exhibits good membrane-permeability and was capable of monitoring at the intracellular Zn²⁺ level in living cells

Parallel Viterbi Decoding Implementation by Multi-microprocessors

The Viterbi algorithm is a well-established technique for channel and source decoding in high performance digital communication systems. However, excessive time consumption makes it difficult to design an efficient highspeed decoder for practical application. The central unit of a Viterbi decoder is a data-dependent feedback loop which performs an add-compare-select (ACS) operation. This nonlinear recurrence is the bottleneck for a high-speed parallel implementation. This paper describes the implementation of parallel Viterbi algorithm by multi-microprocessors. Internal computations are performed in a parallel fashion. The use of microprocessors allows low-cost implementation with moderate complexity. An organization network, separate memory blocks and programs provide proper operation. For a fixed processing speed of given hardware parallel Viterbi decoding allows a linear speed up in the throughput rate by a linear increase in hardware complexity

Galactic diffuse gamma-ray emission from GeV to PeV energies in light of up-to-date cosmic ray measurements

The diffuse gamma-ray emission between 10 and 1000 TeV from the Galactic plane was recently measured by the Large High Altitude Air Shower Observatory (LHAASO). These observations will help tremendously in constraining the propagation and interaction of cosmic rays in the Milky Way. Additionally, new measurements of CR spectra reach a very high precision up to 100 TeV energies, revealing multiple spectral structures of various species. In this work, we confront the model prediction of the diffuse gamma-ray emission, based on up-to-date measurements of the local cosmic ray spectra and simplified propagation setup, with the measurements of diffuse gamma-rays. To better constrain the low-energy part of the model, we analyze the 14.6 years of Fermi-LAT data to extract the Galactic diffuse emission between 1 and 500 GeV from the same sky regions of LHAASO, after subtracting the contribution from known sources and the isotropic diffuse gamma-ray background. The joint Fermi-LAT and LHAASO spectra thus cover a very wide energy range from 1 GeV to 1 PeV with small gaps from 0.5 to 10 TeV. Compared with the prediction, we find that clear excesses between several GeV and ~60 TeV of the diffuse emission exist. Possible reasons to explain the excesses may include unresolved sources or more complicated propagation models. We illustrate that an exponential-cutoff-power-law component with an index of -2.40 and cutoff energy of ~30 TeV is able to account for such excesses