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Abstract Although zinc‒air batteries (ZABs) are regarded as one of the most prospective energy storage devices, their practical application has been restricted by poor air electrode performance. Herein, we developed a free‐standing air electrode that is fabricated on the basis of a multifunctional three‐dimensional interconnected graphene network. Specifically, a three‐dimensional interconnected graphene network with fast mass and electron transport ability, prepared by catalyzing growth of graphene foam on nickel foam and then filling reduced graphene oxide into the pores of graphene foam, is used to anchor iron phthalocyanine molecules with atomic Fe‒N4 sites for boosting the oxygen reduction during discharging and nanosized FeNi hydroxides for accelerating the oxygen evolution during charging. As a result, the obtained air electrode exhibited an ultra‐small electrocatalytic overpotential of 0.603 V for oxygen reactions, a high peak power density of 220.2 mW cm‒2, and a small and stable charge‒discharge voltage gap of 0.70 V at 10 mA cm‒2 after 1136 cycles. Furthermore, in situ Raman spectroscopy together with theoretical calculations confirmed that phase transformation of FeNi hydroxides takes place from α‐Ni(OH)x to β‐Ni(OH)x to γ‐Ni(3+δ)+OOH for the oxygen evolution reaction and Ni is the active center while Fe enhances the activity of Ni active sites.

The capability of computer programming language logic is one of the basics of technical education. How to improve students “interest in program logic design and help overcome students” fears of coding has become vital for educators. Cultivating practical talents with information technology application and basic programming development will become one of the important topics in the department of information related science. The objective of this research is to improve the ability of learning basic programming courses by using Zuvio interactive software. Zuvio employs the mathematical logic of computational thinking to analyze problems and enhance learners’ interest in learning programming skills through a graphical interface tool with building blocks. It uses innovative interactive teaching to use peer and self-assessment to study the content of the course. Zuvio improves the design ability of different groups of class learning Python programming. In line with the innovative teaching policy of the schools and the current stage of the learner’s learning model, learning effectiveness can be achieved. The research results were analyzed by midterm and final experimental group scores, and the progress of the experimental group’s scores was examined through descriptive statistics. The average and standard deviation of the assessment were used to analyze the progress of the experimental group students in the programming course. In the classroom, assessment criteria were set up as the basis for peer assessment scoring. After the midterm and final exams, the teacher assessment and peer assessment scores were analyzed for cognitive differences, and possible learning differences were analyzed. The students’ professional ability was examined to see if it met the professional standards required by the course, and whether innovative teaching methods could improve the learning outcomes of learners with different professional backgrounds in Python programming.

Abstract Can a computer evaluate an athlete’s performance automatically? Many action quality assessment (AQA) methods have been proposed in recent years. Limited by the randomness of video sampling and the simple strategy of model training, the performance of the existing AQA methods can still be further improved. To achieve this goal, a Gaussian guided frame sequence encoder network is proposed in this paper. In the proposed method, the image feature of each video frame is extracted by Resnet model. And then, a frame sequence encoder network is applied to model temporal information and generate action quality feature. Finally, a fully connected network is designed to predict action quality score. To train the proposed method effectively, inspired by the final score calculation rule in Olympic game, Gaussian loss function is employed to compute the error between the predicted score and the label score. The proposed method is implemented on the AQA-7 and MTL–AQA datasets. The experimental results confirm that compared with the state-of-the-art methods, our proposed method achieves the better performance. And detailed ablation experiments are conducted to verify the effectiveness of each component in the module.

Abstract The keen interest in fuel cells and metal‐air batteries stimulates a great deal of research on the development of a cost‐efficient and high‐performance catalyst as an alternative to traditional Pt to boost the sluggish oxygen reduction reaction (ORR) at the cathode. Herein, we report a facile and scalable strategy for the large‐scale preparation of a free‐standing and flexible porous atomically dispersed Fe–N‐doped carbon microtube (FeSAC/PCMT) sponge. Benefiting from its unique structure that greatly facilitates the catalytic kinetics, mass transport, and electron transfer, our FeSAC/PCMT electrode exhibits excellent performance with an ORR potential of 0.942 V at −3 mA cm−2. When the FeSAC/PCMT sponge was directly used as an oxygen electrode for liquid‐state and flexible solid‐state zinc‐air batteries, high peak power densities of 183.1 and 58.0 mW cm−2 were respectively achieved, better than its powdery counterpart and commercial Pt/C catalyst. Experimental and theoretical investigation results demonstrate that such ultrahigh ORR performance can be attributed to atomically dispersed Fe–N5 species in FeSAC/PCMT. This study presents a cost‐effective and scalable strategy for the fabrication of highly efficient and flexible oxygen electrodes, provides a significant new insight into the catalytic mechanisms, and helps to realize significant advances in energy devices.

Abstract Throat auroras and polar cap patches are common phenomena in the polar ionosphere resulting from magnetosphere‐ionosphere coupling. A campaign was organized, with all‐sky imagers at Yellow River Station, the European Incoherent Scatter Svalbard Radar, and coordinated low‐altitude spacecraft observations. During periods of radial interplanetary magnetic field (IMF), observations showed that, as poleward moving throat auroras faded around the polar cap boundary, they linked to poleward moving ionization patches. The throat auroras were produced by soft‐electron precipitation associated with dayside magnetic reconnection. The red line emission intensity of throat auroras was correlated with dayside reconnection events. Dense plasma from lower latitudes was transported poleward via enhanced convection in the throat auroras to form patches. This is a potentially new formation mechanism for patches associated with throat auroras and magnetic reconnection for radial IMF. Moreover, the patches move anti‐sunward due to the E × B drift.

Directional axon regeneration and remyelination are crucial for repair of spinal cord injury (SCI), but existing treatments do not effectively promote those processes. Here, we propose a strategy for construction of niche-specific spinal white matter-like tissue (WMLT) using decellularized optic nerve (DON) loaded with neurotrophin-3 (NT-3)-overexpressing oligodendrocyte precursor cells. A rat model with a white matter defect in the dorsal spinal cord of the T10 segment was used. The WMLT transplantation group showed significant improvement in coordinated motor functions compared with the control groups. WMLT transplants integrated well with host spinal cord white matter, effectively addressing several barriers to directional axonal regeneration and myelination during SCI repair. In WMLT, laminin was found to promote development of oligodendroglial lineage (OL) cells by binding to laminin receptors. Interestingly, laminin could also guide linear axon regeneration via interactions with specific integrins on the axon surface. The WMLT developed here utilizes the unique microstructure and bioactive matrix of DON to create a niche rich in laminin, NT-3 and OL cells to achieve significant structural repair of SCI. Our protocol can help to promote research on repair of nerve injury and construction of neural tissues and organoids that form specific cell niches.

The mechanism underlying neurogenesis during embryonic spinal cord development involves a specific ligand/receptor interaction, which may be help guide neuroengineering to boost stem cell-based neural regeneration for the structural and functional repair of spinal cord injury. Herein, we hypothesized that supplying spinal cord defects with an exogenous neural network in the NT-3/fibroin-coated gelatin sponge (NF-GS) scaffold might improve tissue repair efficacy. To test this, we engineered tropomyosin receptor kinase C (TrkC)-modified neural stem cell (NSC)-derived neural network tissue with robust viability within an NF-GS scaffold. When NSCs were genetically modified to overexpress TrkC, the NT-3 receptor, a functional neuronal population dominated the neural network tissue. The pro-regenerative niche allowed the long-term survival and phenotypic maintenance of the donor neural network tissue for up to 8 weeks in the injured spinal cord. Additionally, host nerve fibers regenerated into the graft, making synaptic connections with the donor neurons. Accordingly, motor function recovery was significantly improved in rats with spinal cord injury (SCI) that received TrkC-modified NSC-derived neural network tissue transplantation. Together, the results suggested that transplantation of the neural network tissue formed in the 3D bioactive scaffold may represent a valuable approach to study and develop therapies for SCI.

Abstract Background Trichinella spiralis (T. spiralis) is a parasite occurring worldwide that has been proven to have antitumour ability. However, studies on the antitumour effects of cross antigens between the tumour and T. spiralis or antibodies against cross antigens between tumours and T. spiralis are rare. Methods To study the role of cross antigens between osteosarcoma and T. spiralis, we first screened the cDNA expression library of T. spiralis muscle larvae to obtain the cross antigen gene tumour protein D52 (TPD52), and prepared fusion protein TPD52 and its antiserum. The anti-osteosarcoma effect of the anti-TPD52 antiserum was studied using cell proliferation and cytotoxicity assays as well as in vivo animal models; preliminary data on the mechanism were obtained using western blot and immunohistochemistry analyses. Results Our results indicated that TPD52 was mainly localized in the cytoplasm of MG-63 cells. Anti-TPD52 antiserum inhibited the proliferation of MG-63 cells and the growth of osteosarcoma in a dose-dependent manner. The tumour inhibition rate in the 100 μg treatment group was 61.95%. Enzyme-linked immunosorbent assay showed that injection of anti-TPD52 antiserum increased the serum levels of IFN-γ, TNF-α, and IL-12 in nude mice. Haematoxylin and eosin staining showed that anti-TPD52 antiserum did not cause significant pathological damage. Apoptosis of osteosarcoma cells was induced by anti-TPD52 antiserum in vivo and in vitro. Conclusions Anti-TPD52 antiserum exerts an anti-osteosarcoma effect by inducing apoptosis without causing histopathological damage. Graphical abstract

AIM: To investigate if there is a gender difference in detecting global motion in adults aged 20-24 years and children aged 6-15 years, respectively.METHODS:A total of 46 adults aged between 20-24 years, and 227 children aged between 6-15 years who were divided into five age groups(6-7 years, 8-9 years, 10-11 years, 12-13 years, and 14-15 years), participated in this study. Global motion detection was evaluated with a random dot kinematogram test, with the proportion of the dots moving at the same direction(up vs down, or left vs right)varied in each trial. The speed of each dot consisted of 1.0 and 5.0 deg/s, therefore four conditions of dots moving were examined in this study. Subjects were asked to identify the direction of the perceived global motion in a three-down-one-up staircase algorithm. The minimal proportion of signal dots moving at the same direction for global motion to be perceived is defined as the threshold. Each subject was measured five times and the mean value was recorded in each condition. Two-way analysis of variance was used for data analysis to accommodate the interaction between the two factors: age and sex maturation.RESULTS:For signal dots moving vertically with 1.0 deg/s, the influence of gender and age on global motion detection was statistically significant(gender: F=10.533, P=0.001; age: F=8.599, P

With the improvement of treatment and prevention methods, many countries have the pandemic under control. Different from the globally large-scale outbreak of COVID-19 in 2020, now the outbreak in these countries shows new characteristics, which calls for an effective epidemic model to describe the transmission dynamics. Meeting this need, first, we extensively investigate the small-scale outbreaks in different provinces of China and use classic compartmental models, which have been widely used in predictions, to forecast the outbreaks. Additionally, we further propose a new version of cellular automata with a time matrix, to simulate outbreaks. Finally, the experimental results show that the proposed cellular automata could effectively simulate the small-scale outbreak of COVID-19, which provides insights into the transmission dynamics of COVID-19 in China and help countries with small-scale outbreaks to determine and implement effective intervention measures. The countries with relatively small populations will also get useful information about the epidemic from our research.

BackgroundGliomas are more malignant and invasive than meningiomas.ObjectiveTo distinguish meningiomas from low-grade/high-grade gliomas (LGGs/HGGs) using amide proton transfer imaging (APT) combined with conventional magnetic resonance imaging (MRI) and to explore the application of APT in evaluating brain tumour invasiveness.Materials and MethodsThe imaging data of 50 brain tumors confirmed by pathology in patients who underwent APT scanning in our centre were retrospectively analysed. Of these tumors, 25 were meningiomas, 10 were LGGs, and 15 were HGGs. The extent of the tumour-induced range was measured on APT images, T2-weighted imaging (T2WI), and MRI enhancement; additionally, and the degree of enhancement was graded. Ratios (RAPT/T2 and RAPT/E) were obtained by dividing the range of changes observed by APT by the range of changes observed via T2WI and MR enhancement, respectively, and APTmean values were measured. The Mann–Whitney U test was used to compare the above measured values with the pathological results obtained for gliomas and meningiomas, the Kruskal-Wallis test was used to compare LGGs, HGGs and meningiomas, and Dunn’s test was used for pairwise comparisons. In addition, receiver operating characteristic (ROC) curves were drawn.ResultsThe Mann–Whitney U test showed that APTmean (p=0.005), RAPT/T2 (p

The expression of major histocompatibility complex class I (MHC-I), a key antigen-presenting protein, can be induced in dopaminergic neurons in the substantia nigra, thus indicating its possible involvement in the occurrence and development of Parkinson's disease. However, it remains unclear whether oxidative stress induces Parkinson's disease through the MHC-I pathway. In the present study, polymerase chain reaction and western blot assays were used to determine the expression of MHC-I in 1-methyl-4-phenylpyridinium (MPP+)-treated SH-SY5Y cells and a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease mouse model. The findings revealed that MHC-I was expressed in both models. To detect whether the expression of MHC-I was able to trigger the infiltration of cytotoxic T cells, immunofluorescence staining was used to detect cytotoxic cluster of differentiation 8 (CD8)+ T cell infiltration in the substantia nigra of MPTP-treated mice. The results indicated that the presentation of MHC-I in dopaminergic neurons was indeed accompanied by an increase in the number of CD8+ T cells. Moreover, in MPTP-induced Parkinson's disease model mice, the genetic knockdown of endogenous MHC-I, which was caused by injecting specific adenovirus into the substantia nigra, led to a significant reduction in CD8+ T cell infiltration and alleviated dopaminergic neuronal death. To further investigate the molecular mechanisms of oxidative stress-induced MHC-I presentation, the expression of PTEN-induced kinase 1 (PINK1) was silenced in MPP+-treated SH-SY5Y cells using specific small interfering RNA (siRNA), and there was more presentation of MHC-I in these cells compared with control siRNA-treated cells. Taken together, MPP+-/MPTP-induced oxidative stress can trigger MHC-I presentation and autoimmune activation, thus rendering dopaminergic neurons susceptible to immune cells and degeneration. This may be one of the mechanisms of oxidative stress-induced Parkinson's disease, and implies the potential neuroprotective role of PINK1 in oxidative stress-induced MHC-I presentation. All animal experiments were approved by the Southern Medical University Ethics Committee (No. 81802040, approved on February 25, 2018).

Abstract This paper proposes a new neural network learning method to improve the performance for action recognition in video. Most human action recognition methods use a clip-level training strategy, which divides the video into multiple clips and trains the feature learning network by minimizing the loss function of clip classification. The video category is predicted by the voting of clips from the same video. In order to obtain more effective action feature, a new video-level feature learning method is proposed to train 3D CNN to boost the action recognition performance. Different with clip-level training which uses clips as input, video-level learning network uses the entire video as the input. Consistent constraint loss is defined to minimize the distance between clips of the same video in voting space. Further, a video-level loss function is defined to compute the video classification error. The experimental results show that the proposed video-level training is a more effective action feature learning approach compared with the clip-level training. And this paper has achieved the state-of-the-art performance on UCF101 and HMDB51 datasets without using pre-trained models of other large-scale datasets. Our code and final model are available at https://github.com/hqu-cst-mmc/VLL .

AIM: To assess the consistency of refractive errors measured by two autorefractors in myopia screening of school-age Chinese children.METHODS: Topcon RM-8900 and Tianle RM-9000 autorefractors were utilized to measure refractive errors under noncycloplegic condition in students aged 6 to 16 years old who were cluster sampled from four primary and secondary schools in Dongli district, Tianjin. Sperman correlation analysis and Bland-Altman method were used to evaluate the consistency of spherical diopters, cylindrical diopters and spherical equivalents measured by the two methods, and the axial difference distribution of astigmatism measured by the two methods was analyzed.RESULTS:A total of 2 276 eyes of 1 138 subjects with a mean age of 10.49±2.66 a were finally enrolled. Spearman correlation analysis showed that sphere(r=0.958, Pr=0.769, Pr=0.962, PPCI: -0.27, 1.16)while the maximum absolute value(1.13 D)of the difference within the 95% CI was above the clinically acceptable range; however, no significant difference(P=0.83)was found between cylindrical diopters measured by the two methods with a mean difference of -0.01 D(SD: 0.31; 95% CI=-0.62, 0.61)while the maximum absolute value(0.62 D)of the difference within the 95% CI was clinically acceptable. The proportion of the axial deviation within ±20° was 84.6%(1 503/1 777)in eyes with cylinder ≤-0.25D while that rose to 96.4%(853/885)in eyes with cylinder ≤-0.75D. CONCLUSION: Spherical diopters measured by Tianle RM-9000 have a significant hyperopia bias than those measured by Topcon RM-8900 while the consistency of cylindrical diopters and cylindrical axes is clinically acceptable.

Background: Septic shock, the most serious complication of sepsis, is a life-threatening disease that is mainly characterized by hypoperfusion and multiple organ failure. Various aberrantly expressed microRNAs (miRNAs) have been reported to be related to septic shock. We explored the regulatory effect of microRNA-203 (miR-203) on lung injury in septic shock mice. Methods: Microarray-based gene expression profiling related to septic shock identified the differentially expressed gene vanin-1 (VNN1) and potential regulatory miR-203. miR-203 was predicted to mediate VNN1 expression, thus affecting septic shock, which was investigated by treatment with miR-203 mimic, miR-203 inhibitor, and siRNA-VNN1 in septic shock mouse models. Polymorphonuclear neutrophils (PMNs) and pulmonary alveolar macrophages in bronchoalveolar lavage fluid (BALF) as well as the wet/dry ratio of the lung were also measured to assess lung injury. Additionally, the effects of miR-203 on inflammatory cytokines, oxidative stress indexes, blood biochemical indexes, serine-threonine protein kinase (AKT) signaling pathway-related factors, and apoptosis-related factors were determined. Results: VNN1 was verified to be targeted and negatively regulated by miR-203. In mouse models of septic shock, weak expression of miR-203, high expression of VNN1, and inhibition of AKT signaling pathway were identified. In response to miR-203 mimic and VNN1 gene silencing, mouse models of septic shock displayed reduced apoptosis, MDA, ALT, and AST in lung tissues, decreased levels of TNF-α, IL-1β, IFN-γ, IL-10, and IL-6, in serum, and reduced PMN and PAM levels in BALF, in addition to elevated SOD activity. Notably, the presence of miR-203 mimic led to AKT signaling pathway activation. Conclusion:This study shows that upregulating miR-203 can alleviate lung injury through activation of the AKT signaling pathway by downregulating VNN1 in septic shock.

As a new paradigm of information technology, the Internet of Things (IoT) is attracting increasing attention from various industrial fields. It is foreseeable that the applications of IoT will be prevalent in the public transportation system and bring changes to the system in the near future. In this paper, we analyze the impact of IoT environment on the public transportation system, propose a new framework of the intelligent public transportation system based on IoT, and present the deployment of the elements, the communication network, and the three-tier architecture of the system in detail. We also present the information flow, technical scheme, optimization model, and algorithm of the main modules of dynamic optimization of the system. The innovative points of this paper lie in: (1) a new framework for public transport system based on IoT, which integrates the scheduling problems of subway, bus, and shared taxi, is proposed for better-coordinated transfer solutions; (2) transport flow prediction methods based on periodic patterns mining is proposed for road flow analysis and passenger flow analysis, and; (3) mathematical model and DSS-based evolutionary computation algorithm are proposed for solving the dynamic bus scheduling and controlling problems. The proposed intelligent transport system based on IoT can assist the decision makers to increase the utilization rate of the transport resources, improve the efficiency of scheduling, and reduce passengers' traveling time.

Background Paroxysmal tonic upgaze (PTU) is an infantile-onset paroxysmal neurological disorder that is characterized by episodes of sustained conjugate upward eye deviation. The paroxysmal abnormal eye movements need to be differentiated from seizures. We report a case of PTU with occipital discharge on electroencephalography (EEG), which made the diagnosis more complicated. Case presentation A 6-month-old girl presented with paroxysmal upward deviation or left strabismus of the eyes, with a bowed head, lowered jaw, raised eyebrows, closed lips, and slight grin. Each episode lasted for a few seconds, and episodes occurred multiple times per day. EEG showed spike waves in the right occipital region, and the girl was initially misdiagnosed with epilepsy. After further analysis using video EEG, we corrected her diagnosis as PTU and stopped the administration of an antiepileptic drug. Conclusion PTU accompanied by discharge on EEG may lead to a misdiagnosis. Video EEG monitoring, and especially the analysis of EEG traces synchronized with attacks, can provide evidence to distinguish between seizures and non-epileptic events.

Most existing methods of motion assessment system used the contact sensor, infrared sensor, and depth sensor, and few works provided the solution of digital camera. To solve this problem, the authors propose a new motion assessment system based on light camera. In this work, the motion assessment was regarded as pattern regression problem of skeleton joint trajectory. Firstly, the system uses the camera to capture the image sequences. The pose estimation method is used to obtain body skeleton from image. Secondly, due to the difference of motion frequency of each person, the length of the image sequences is different and the length of each joint trajectory also will be different. Fourier transform is applied to normalise the trajectory and use the coefficients of Fourier transform as the joint trajectory feature. Finally, the regression model is built to assess the motion quality. Some experimental results and discussion on action video data are used to verify the effectiveness of the system.

Long-term domestication and selective breeding have increased the silk yield of the domestic silkworm (Bombyx mori) by several times the amount of the silk yield of its wild ancestor (Bombyx mandarina). However, little is known about the molecular mechanisms behind the increase in silk yield during domestication. Based on dynamic patterns of functional divergence in the silk gland between domestic and wild silkworms, we found that at early and intermediate stages of silk gland development, the up-regulated genes of the domestic silkworm were mainly involved in DNA integration, nucleic acid binding, and transporter activity, which are related to the division and growth of cells. This has led to the posterior silk gland (PSG) of the domestic silkworm having significantly more cells (“factories” of fibroin protein synthesis) than that of the wild silkworm. At the late stage of silk gland development, the up-regulated genes in the domestic silkworm was enriched in protein processing and ribosome pathways, suggesting protein synthesis efficiency is greatly improved during silkworm domestication. While there was an increase in fibroin protein synthesis, the production of sericin protein was simultaneously reduced in the silk gland of the domestic silkworm. This reflects that domestic and wild silkworms have been under different selection pressures. Importantly, we found that the network co-expressed with the silk-coding genes of the domestic silkworm was larger than that of the wild silkworm. Furthermore, many more genes co-expressed with silk-coding genes in the domestic silkworm were subjected to artificial selection than those in the wild silkworm. Our results revealed that the increase of silk yield during silkworm domestication is involved in improvement of a biological system which includes not only expansion of “factories” (cells of PSG) of protein synthesis, but also a high expression of silk-coding genes and silk production-related genes such as biological energy, transport, and ribosome pathway genes.

This paper presents an experimental demonstration of 100-Gbps timeand wavelength-division multiplexed passive optical network (TWDM-PON) with 4 × 25-Gbps downstream transmission. We take a comparison of faster-than-Nyquist nonreturn-to-zero (FTN-NRZ), four-level pulse amplitude modulation (PAM-4), electrical duobinary (EDB), and optical duobinary (ODB) on the same transmission link. The use of low-cost 10-Gbps optics in combination with digital signal processing (DSP) makes it feasible for a 25-Gb/s per wavelength transmission over 20-km standard single-mode fiber (SSMF) in a cost-effective way. The spectra efficiency and ISI robustness by going to the higher rate are analyzed theoretically. We achieve link budgets of 33.18 dB for FTN-NRZ, and less than 30 dB budgets for PAM-4, ODB, and EDB in downstream transmission. FTN combination with feedforward equalization (FFE) allows FTN-NRZ to have a 4.18 dB margin in power requirement of PR(x) 30 of 10G-EPON, whereas PAM-4 and ODB with FFE also meet PR(x) 30 with 0.25 dB margin. The results indicate that FTN-NRZ, PAM-4, and ODB can be used for 100G-EPON with 10-Gbps optics, and FTN-NRZ has better performance than other modulations, which is more suitable for next-generation 100G-EPON transmission technique with low cost.

Action recognition is one of the hottest research topics in computer vision. Recent methods represent actions based on global or local video features. These approaches, however, lack semantic structure and may not provide a deep insight into the essence of an action. In this work, the authors argue that semantic clues, such as joint positions and part‐level motion clustering, help verify actions. To this end, a meta‐action descriptor for action recognition in RGBD video is proposed in this study. Specifically, two discrimination‐based strategies – dynamic and discriminative part clustering – are introduced to improve accuracy. Experiments conducted on the MSR Action 3D dataset show that the proposed method significantly outperforms the methods without joint position semantic.

In this study, the authors investigate the possibility of boosting action recognition performance by exploiting the associated scene context. Towards this end, the authors model a scene as a mid‐level ‘middle layer’ in order to bridge action descriptors and action categories. This is achieved via a scene topic model, in which hybrid visual descriptors, including spatial–temporal action features and scene descriptors, are first extracted from a video sequence. Then, the authors learn a joint probability distribution between scene and action using a naive Bayes nearest neighbour algorithm, which is adopted to jointly infer the action categories online by combining off‐the‐shelf action recognition algorithms. The authors demonstrate the advantages of their approach by comparing it with state‐of‐the‐art approaches using several action recognition benchmarks.

In this review, we focused on a few obstacles that hinder three-dimensional (3D) bioprinting process in tissue engineering. One of the obstacles is the bioinks used to deliver cells. Hydrogels are the most widely used bioink materials; however, they are mechanically weak in nature and cannot meet the requirements for supporting structures, especially when the tissues, such as cartilage, require extracellular matrix to be mechanically strong. Secondly and more importantly, tissue regeneration is not only about building all the components in a way that mimics the structures of living tissues, but also about how to make the constructs function normally in the long term. One of the key issues is sufficient nutrient and oxygen supply to the engineered living constructs. The other is to coordinate the interplays between cells, bioactive agents and extracellular matrix in a natural way. This article reviews the approaches to improve the mechanical strength of hydrogels and their suitability for 3D bioprinting; moreover, the key issues of multiple cell lines coprinting with multiple growth factors, vascularization within engineered living constructs etc. were also reviewed.

A new and efficient synthetic method to obtain fully-substituted hexahydroisoindolinones was developed by using bifunctional tertiary amine-thioureas as powerful catalysts. As far as we know, there is no efficient synthetic method developed toward fully-substituted hexahydroisoindolinones. The products were obtained in good yield and diastereoselectivity. The one-pot cascade quadruple protocol features readily available starting materials, simple manipulation, mild conditions and good atom economy.

Objective To establish database for brain tumor patients with mood disorders and to explore the status and epidemiological characteristics of emotional function. Methods By using computer software, establish database of brain tumor with affective disorder based on clinical requirements. Record the data of 140 cases of brain tumors undergoing operation treatment, so as to found perfect public data platform and realize resource sharing. Results The clinical data of 140 brain tumor patients were successfully filled in the registration query system. The database provides simple and complex mood data queries for users to browse. Conclusions The mood disorder database for patients with brain tumors can provide related data samples and resources for basic and clinical research. Besides, it can effectively share clinical research data and reduce research costs. DOI: 10.3969/j.issn.1672-6731.2015.09.010

With this study, we propose a method to image the tip crack on transparent materials by using digital holographic microscopy. More specifically, an optical system based on Mach−Zehnder interference along with an inverted microscopy (Olympus CKX53) was used to image the tip crack of Dammar Varnish transparent material under thermal excitation. A series of holograms were captured and reconstructed for the observation of the changes of the tip crack. The reconstructed holograms were also compared temporally to compute the temporal changes, showing the crack propagation phenomena. Results show that the Dammar Varnish is sensitive to the ambient temperature. Our research demonstrates that digital holographic microscopy is a promising technique for the detection of the fine tip crack and propagation in transparent materials.

The fields of human activity analysis have recently begun to diversify. Many researchers have taken much interest in developing action recognition or action prediction methods. The research on human action evaluation differs by aiming to design computation models and evaluation approaches for automatically assessing the quality of human actions. This line of study has become popular because of its explosively emerging real-world applications, such as physical rehabilitation, assistive living for elderly people, skill training on self-learning platforms, and sports activity scoring. This paper presents a comprehensive survey of approaches and techniques in action evaluation research, including motion detection and preprocessing using skeleton data, handcrafted feature representation methods, and deep learning-based feature representation methods. The benchmark datasets from this research field and some evaluation criteria employed to validate the algorithms’ performance are introduced. Finally, the authors present several promising future directions for further studies.

The terminal guidance problem of hypersonic gliding missiles under multiple constraints was considered regarding a coordinated attack in time and space. In this paper, a three-dimensional terminal guidance method based on the real-time updating of parameters is proposed with consideration to the attack time and terminal angle. By this method, the three-dimensional motion was decomposed into the horizontal and vertical plane. In each plane, a real-time solution of the optimal trajectory yielded angle commands that satisfied the terminal angle constraints. Additionally, the time was controlled by changing the flight path angle in the front section of the vertical plane. The results obtained by numerical simulation indicated the good applicability and robustness of this method.

Multiple-bud regeneration, i.e., multiple amplification, has been shown to exist in peripheral nerve regeneration. Multiple buds grow towards the distal nerve stump during proximal nerve fiber regeneration. Our previous studies have verified the limit and validity of multiple amplification of peripheral nerve regeneration using small gap sleeve bridging of small donor nerves to repair large receptor nerves in rodents. The present study sought to observe multiple amplification of myelinated nerve fiber regeneration in the primate peripheral nerve. Rhesus monkey models of distal ulnar nerve defects were established and repaired using muscular branches of the right forearm pronator teres. Proximal muscular branches of the pronator teres were sutured into the distal ulnar nerve using the small gap sleeve bridging method. At 6 months after suture, two-finger flexion and mild wrist flexion were restored in the ulnar-sided injured limbs of rhesus monkey. Neurophysiological examination showed that motor nerve conduction velocity reached 22.63 ± 6.34 m/s on the affected side of rhesus monkey. Osmium tetroxide staining demonstrated that the number of myelinated nerve fibers was 1,657 ± 652 in the branches of pronator teres of donor, and 2,661 ± 843 in the repaired ulnar nerve. The rate of multiple amplification of regenerating myelinated nerve fibers was 1.61. These data showed that when muscular branches of the pronator teres were used to repair ulnar nerve in primates, effective regeneration was observed in regenerating nerve fibers, and functions of the injured ulnar nerve were restored to a certain extent. Moreover, multiple amplification was subsequently detected in ulnar nerve axons.

Schizophrenia (SCZ) is a severe and debilitating mental disorder, and the specific genetic factors that underlie the risk for SCZ remain elusive. The autism susceptibility candidate 2 (AUTS2) gene has been reported to be associated with autism, suicide, alcohol consumption, and heroin dependence. We hypothesized that AUTS2 might be associated with SCZ. In the present study, three polymorphisms (rs6943555, rs7459368, and rs9886351) in the AUTS2 gene were genotyped in 410 patients with SCZ and 435 controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and forced PCR-RFLP methods. We detected an association between SCZ and the rs6943555 genotype distribution (odds ratio (OR) = 1.363, 95% confidence interval (CI): 0.848–2.191, p = 0.001). The association remained significant after adjusting for gender, and a significant effect (p = 0.001) was observed among the females. In the present study, rs6943555 was determined to be associated with female SCZ. Our results confirm previous reports which have suggested that rs6943555 might elucidate the pathogenesis of schizophrenia and play an important role in its etiology.

Motion estimation is a basic issue for many computer vision tasks, such as human–computer interaction, motion objection detection and intelligent robot. In many practical scenes, the object movement goes with camera motion. Generally, motion descriptors directly based on optical flow are inaccurate and have low discrimination power. To this end, a novel motion correction method is proposed and a novel motion feature descriptor called the motion difference histogram (MDH) for recognising human action is proposed in this study. Motion estimation results are corrected by background motion estimation and MDH encodes the motion difference between the background and the objects. Experimental results on video shot with camera motion show that the proposed motion correction method is effective and the recognition accuracy of MDH is better than that of the state-of-the-art motion descriptor.

Although widely used in many applications, accurate and efficient human action recognition remains a challenging area of research in the field of computer vision. Most recent surveys have focused on narrow problems such as human action recognition methods using depth data, 3D-skeleton data, still image data, spatiotemporal interest point-based methods, and human walking motion recognition. However, there has been no systematic survey of human action recognition. To this end, we present a thorough review of human action recognition methods and provide a comprehensive overview of recent approaches in human action recognition research, including progress in hand-designed action features in RGB and depth data, current deep learning-based action feature representation methods, advances in human⁻object interaction recognition methods, and the current prominent research topic of action detection methods. Finally, we present several analysis recommendations for researchers. This survey paper provides an essential reference for those interested in further research on human action recognition.

Background & Objective: Nasopharyngeal carcinoma (NPC) is an epithelial neoplasm with high occurrence rates in southern China. The disease often metastasizes to regional lymphnodes at a very early stage. Local recurrences and metastasis occur frequently in patients with NPC and are a leading cause of death, despite improvements on treatment modalities. The molecular mechanism underlying the metastasis of nasopharyngeal carcinoma remains poorly understood, however, and requires additional elucidation. The aim of this study was to explore possible NPC gene candidates that may play key roles in NPC metastasis. Methods: Subtractive suppression hybridization (SSH) was performed to isolate differentially expressed clones between the metastatic 5-8F and non-metastatic 6-10B nasopharyngeal carcinoma cell lines. Differentially expressed clones were screened and confirmed by reverse Northern blotting. The sequences of cDNA fragments were subsequently analyzed and compared to known sequences in Genbank. Results & Discussion: The SSH library contained thousands of positive clones. Random analysis of 300 clones by PCR demonstrated that 269 clones contained inserted fragments. Reverse Northern blot confirmed that 20 out of 192 clones examined were significantly up-regulated in the 5-8F cell line. Among these 20 clones, 16 were previously identified genes (flotilin-2, ezrin, pim-3, fli-1, mel, neugrin, znf216, ASB1, raly, UBE2A, keratin6A, TMED7, EIF3S9, FTL, two ribosomal proteins RPL21 and RPL16), two were predicted genes (c9orf74 and MDS006), and two sequences shared no homology with known genes listed in GenBank and may represent novel genes. The proposed functions of the genes identified in this study include cell signal transduction, cell survival, transcription regulation, cell mobility, protein synthesis, and DNA damage repair. Flotillin-2, fli-1, pim-3 and ezrin have previously been reported to be associated with tumor metastasis and progression. The remaining up-regulated genes identified in this study have not been reported to be markers of metastasis and may represent new candidates of NPC metastasis-related genes. The Results of this study may provide novel points of therapeutic intervention for NPC.

The capability of computer programming language logic is one of the basics of technical education. How to improve students "interest in program logic design and help overcome students" fears of coding has become vital for educators. Cultivating practical talents with information technology application and basic programming development will become one of the important topics in the department of information related science. The objective of this research is to improve the ability of learning basic programming courses by using Zuvio interactive software. Zuvio employs the mathematical logic of computational thinking to analyze problems and enhance learners' interest in learning programming skills through a graphical interface tool with building blocks. It uses innovative interactive teaching to use peer and self-assessment to study the content of the course. Zuvio improves the design ability of different groups of class learning Python programming. In line with the innovative teaching policy of the schools and the current stage of the learner's learning model, learning effectiveness can be achieved. The research results were analyzed by midterm and final experimental group scores, and the progress of the experimental group's scores was examined through descriptive statistics. The average and standard deviation of the assessment were used to analyze the progress of the experimental group students in the programming course. In the classroom, assessment criteria were set up as the basis for peer assessment scoring. After the midterm and final exams, the teacher assessment and peer assessment scores were analyzed for cognitive differences, and possible learning differences were analyzed. The students' professional ability was examined to see if it met the professional standards required by the course, and whether innovative teaching methods could improve the learning outcomes of learners with different professional backgrounds in Python programming.

The vacuum diode which is used to generate relativistic electron beams is one of the most important parts of a pulsed-power modulator. In this paper, the electron emission of cathode holder of a vacuum diode and its effect on the output voltage is investigated by experiments on an intense electron-beam accelerator with 180 ns full width at half maximum and 200–500 kV output voltage. First, the field emission is analyzed and the electric field of the vacuum chamber is calculated. Then, the flatness of the output voltage is discussed before and after adding an insulation plate when a water load is used. It is found that the electron emission at the edges of the cathode holder is the main reason to cause the change of the flatness. Last, a piece of polyester film is used as a target to further show the electron emission of the cathode holder. This analysis shows that decreasing the electron emission of the cathode holder in such a pulse power modulator could be a good way to improve the quality of the output voltage.

The Blumlein pulse forming line (BPFL) consisting of an inner coaxial pulse forming line (PFL) and an outer coaxial PFL is widely used in the field of pulsed power, especially for intense electron-beam accelerators (IEBA). The output voltage waveform determines the quality and characteristics of the output beam current of the IEBA. Comparing with the conventional BPFL, an IEBA based on a helical type BPFL can increase the duration of the output voltage in the same geometrical volume. However, for the helical type BPFL, the voltage waveform on a matched load may be distorted which influences the electron-beam quality. In this paper, an IEBA based on helical type BPFL is studied theoretically. Based on telegrapher equations of the BPFL, a formula for the output voltage of IEBA is obtained when the transition section is taken into account, where the transition section is between the middle cylinder of BPFL and the load. From the theoretical analysis, it is found that the wave impedance and transit time of the transition section influence considerably the main pulse voltage waveform at the load, a step is formed in front of the main pulse, and a sharp spike is also formed at the end of the main pulse. In order to get a well-shaped square waveform at the load and to improve the electron-beam quality of such an accelerator, the wave impedance of the transition section should be equal to that of the inner PFL of helical type BPFL and the transit time of the transition section should be designed as short as possible. Experiments performed on an IEBA with the helical type BPFL show reasonable agreement with theoretical analysis.