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Accurately parsing (i.e., segmenting and recognizing) muscles of freely-moving animals such as Drosophila larva in light-sheet fluorescence microscopy images is necessary to study the relationship between muscle activity and animal motions. However, this task is challenging due to the large inter-class similarity and intra-class variance of muscles, as well as the in-homogeneous intensity and blurred boundaries of neighboring muscles. Existing semantic and instance segmentation methods cannot effectively overcome these challenges, resulting in poor segmentation and unreliable classification. In this work, we propose a novel framework named MuscleParseNet that explicitly utilizes sequential and spatial contexts to address these challenges. MuscleParseNet contains a deformable muscle candidate detector (D-CMD) to detect candidate muscles, and a sequential and spatial context-based fine muscle parser (SS-FMP) to refine the candidates. D-CMD boosts Mask RCNN with deformable convolutions to capture shape variations for more accurate muscle segmentation. Moreover, SS-FMP re-classifies the detected candidates by establishing a global spatial context to explicitly reflect spatial relative location, then optimizes the classification using the sequential associations of candidates in adjacent frames, which significantly improves muscle recognition accuracy. Experiments on the synchronized muscle-motion dataset of nearly freely-moving larvae show that MuscleParseNet produces promising results, outperforming state-of-the-art semantic and instance segmentation methods.

Trapezoidal shaping algorithms are often used when digitally processing spectrum detector signals to reduce the ballistic deficit, improve energy resolution, and increase the count rate. In the digital trapezoid shaping algorithm, adjusting the rise and flat-top times of the trapezoid is easy. The two stacked exponential pulses can be shaped into two peak-distinguishable trapezoids, allowing them to be preserved during pile-up rejection processing. The pulse signal output by the energy spectrum detector usually needs to be converted into a pulse that is near exponential decay through a charge-sensitive preamplifier. However, the effects of detector aging and temperature drift can always change the decay constant of the output signal, which may severely distort the shaped trapezoidal signal and reduce the energy resolution of the detector. In this article, based on the digital synthesis of pulse shapes, we propose using the fast Fourier transform (FFT) algorithm to calculate the decay constant of the exponential pulse. This method can adaptively evolve new shapers according to different detector characteristics and support a fast calibration procedure to match different noise spectra and address unpredictable signal fluctuations. The adaptive trapezoidal shaping system was implemented in the field-programmable gate array (FPGA), and the relative error of the coefficients obtained from the system was verified by simulation and experimentation to be within 0.8%.

Herein, we report three cationic photocurable polymethylsiloxane/eugenol-modified oxetane monomers (Eugenol-Sin, n= 3, 6, 9). Eugenol-Sinmonomers can polymerize well in the presence of a photoinitiator under irradiation and promote the opening ring reaction of the ternary oxygen heterocycle monomer (E4221). The final conversions of oxirane and oxetane groups for E/Eugenol-Sincomposed of E4221 and Eugenol-Sinare 73.3% and about 74.0% respectively, which were higher than those of nopol-based monomers previously reported by us. The rigid benzene ring of eugenol and the soft thermostable hydrophobic polymethylsiloxane chain can endow UV-cured films with good hydrophobicity, heat resistance, and tensile properties. Thus, the water contact angles of E/Eugenol-Sinreach up to 94.2°. Moreover, the lengthening of the polymethylsiloxane chain length can enhance not only the heat resistance but also the tensile performance of E/Eugenol-Sinbut reduce glass transition temperature (Tg). Furthermore, when the added amount of Eugenol-Sinincreases, the heat resistance and tensile performance of E/Eugenol-Si9rise first and subsequently decline, but the glass transition temperature shows a trend of continuous decrease. Besides, compared with nopol-based monomers, Eugenol-Sinexhibit a much better thermostability. Eugenol-Sindemonstrate a great practical application perspective owing to advantages in terms of cost and performances.

The authors study the Nehari family Nb and obtain some important properties for this family.