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Flexible and diverse manipulation of electromagnetic (EM) waves in half space (reflection or transmission) has facilitated strong aspiration toward full-space wave control. However, it remains challenging to achieve independent amplitude and phase control, which seriously hinder the real-world applications. Herein, an innovative strategy of trifunctional metasurface is proposed to independently and simultaneously manipulate the amplitude and phase of circular polarized waves in full space. The multifunctional design is composed of double-layer anisotropic metasurface sandwiched with a bandpass frequency selective surface, with a frequency-direction multiplexed paradigm for on-demand control of both amplitude and phase across three independent channels. To validate the concept, a multifunctional metadevice is designed and verified by simulations and experiments, showcasing arbitrary near-field and far-field power modulation in full space. Lateral and axial bifocal metalenses with desired intensity distribution are designed in two reflection channels at 9 GHz, while multibeam generator with desired spatial scatterings and power allocations is designed in transmissive channel at 13 GHz. The finding paves the way for attaining multifunctional metadevices with amplitude and phase modulation in full space, which have potential applications in high-quality imaging and high-capacity communication systems.

BigNeuron is an open community bench-testing platform with the goal of setting open standards for accurate and fast automatic neuron tracing. We gathered a diverse set of image volumes across several species that is representative of the data obtained in many neuroscience laboratories interested in neuron tracing. Here, we report generated gold standard manual annotations for a subset of the available imaging datasets and quantified tracing quality for 35 automatic tracing algorithms. The goal of generating such a hand-curated diverse dataset is to advance the development of tracing algorithms and enable generalizable benchmarking. Together with image quality features, we pooled the data in an interactive web application that enables users and developers to perform principal component analysis, t-distributed stochastic neighbor embedding, correlation and clustering, visualization of imaging and tracing data, and benchmarking of automatic tracing algorithms in user-defined data subsets. The image quality metrics explain most of the variance in the data, followed by neuromorphological features related to neuron size. We observed that diverse algorithms can provide complementary information to obtain accurate results and developed a method to iteratively combine methods and generate consensus reconstructions. The consensus trees obtained provide estimates of the neuron structure ground truth that typically outperform single algorithms in noisy datasets. However, specific algorithms may outperform the consensus tree strategy in specific imaging conditions. Finally, to aid users in predicting the most accurate automatic tracing results without manual annotations for comparison, we used support vector machine regression to predict reconstruction quality given an image volume and a set of automatic tracings.

Objectives: Evidence on the link between long-term ambient particulate matter (PM) exposures and childhood sleep disorders were scarce. We examined the associations between long-term exposures to PM2.5 and PM1 (PM with an aerodynamic equivalent diameter

Neurexins play diverse functions as presynaptic organizers in various glutamatergic and GABAergic synapses. However, it remains unknown whether and how neurexins are involved in shaping functional properties of the glycinergic synapses, which mediate prominent inhibition in the brainstem and spinal cord. To address these issues, we examined the role of neurexins in a model glycinergic synapse between the principal neuron in the medial nucleus of the trapezoid body (MNTB) and the principal neuron in the lateral superior olive (LSO) in the auditory brainstem. Combining RNAscope with stereotactic injection of AAV-Cre in the MNTB of neurexin1/2/3 conditional triple knockout mice, we showed that MNTB neurons highly express all isoforms of neurexins although their expression levels vary remarkably. Selective ablation of all neurexins in MNTB neurons not only reduced the amplitude but also altered the kinetics of the glycinergic synaptic transmission at LSO neurons. The synaptic dysfunctions primarily resulted from an impaired Ca2+ sensitivity of release and a loosened coupling between voltage-gated Ca2+ channels and synaptic vesicles. Together, our current findings demonstrate that neurexins are essential in controlling the strength and temporal precision of the glycinergic synapse, which therefore corroborates the role of neurexins as key presynaptic organizers in all major types of fast chemical synapses.

Impatiens is rich in germplasm resources, with more than 260 species in China. A study on the pollen micromorphology of Impatiens by scanning electron microscopy (SEM) showed that the pollen characteristics were richly diverse, and there was some correlation among the characteristics. In addition, the micromorphological index can be used for an effective cluster analysis of Impatiens. However, there was high interspecific similarity in some Impatiens, and the classification of Impatiens cannot be accurate to the species using pollen characteristics. Based on the classification conditions of Impatiens, the characteristics of the pollen structure were found to be useful to classify Impatiens into subgenera or smaller groups. The macroscopic characteristics and the number of sepals (NS) were used as references, which enabled the conclusion that there were 11 indices in the pollen micromorphological index, and the taxonomic effect was greater than the NS. In summary, the pollen micromorphology of Impatiens plays an important role in the classification of Impatiens. The purpose of this study was to explore this characteristic of Impatiens, which has some reference significance to supplement the pollen characteristics and palynological classification of Impatiens. The goal for this research was to aid in the interspecific identification and genetic breeding of Impatiens.

Exploring rural employment and entrepreneurship of undergraduate graduates in the context of rural revitalization strategy is conducive to providing human resources for rural revitalization. This paper starts from the Gaussian mixture model, introduces the specific principle of the Gaussian mixture model, then introduces the EM algorithm under the data mining algorithm, and points out that the EM algorithm is often used as an iterative optimization method for great likelihood estimation, and explains the principle and process steps of the algorithm in detail. The EM algorithm is used to solve the logarithmic great likelihood estimate of the Q function with conditional probability density function, and then the EM algorithm is applied to the Gaussian mixture model to update the values of its parameters, and the performance of the EM-GMM algorithm is also evaluated. Finally, the EM-GMM algorithm analyzes the impact of employment unit preference and employment promotion policies on the undergraduate graduates of four universities in a certain area. From the performance evaluation, the algorithm’s accuracy in this paper is 94.54%, which is 21.29 and 5.02 percentage points higher than that of the K-means-EM algorithm and FCM-EM algorithm, respectively. Regarding employment unit preference, 45.82% and 22.09% of undergraduate graduates are more inclined to be employed in township government agencies, state-owned enterprises, and institutions. Promoting rural employment and entrepreneurship of undergraduate graduates requires strengthening employment guidance and employment concept correction to provide fresh blood for rural revitalization.

This research aimed to establish a determination of thiourea in wheat flour and its products of high performance liquid chromatography (HPLC) method. Thioureas in wheat flour and noodle samples were extracted with pure water under ultrasonic conditions at 25 ℃ for 15 min. After centrifugation and filtration, they were separated by Agilent ZORBAX SB-C18 column with mobile phase of 0.02 mol/L phosphoric acid-disodium hydrogen phosphate buffer solution (pH=3) + methanol =98+2. The detection wavelength was 236 nm, and the quantitative method was external standard. The range of thiourea was 0~20.0 μg/mL and the linear relationship was good (correlation coefficient r=0.999 99). The limit of detection (S/N=3) was 0.5 mg/kg and the limit of quantification (S/N=10) was 1.5 mg/kg. The spiked recovery test and precision test were carried out on wheat flour and surface samples at three levels of method detection limit, 2 times method detection limit and 10 times method detection limit. All the test results met the requirements of spiked recovery and precision in Appendix F of GB/T 27404—2008 . The method was accurate, stable and reliable for the determination of thiourea in wheat flour and its products.

The research progress in dynamically vulcanized polyurethane/silicone rubber thermoplastic elastomer was summarized from the aspects of raw material selection, processing technology and compatibilizer with 20 references.