Search

Multitrack music generation technology is becoming more and more mature, but the existing generation technology cannot reach the desired effect in terms of harmony and matching degree, and most of the generated music does not conform to the music theory knowledge. In order to solve these problems, we propose a multitrack music generation network based on transformer to produce music with high musicality under the guidance of music theory rules. This paper uses an improved version of transformer to learn the information inside a single-track sequence and between different tracks. Then, a combination of music theory rules and crossentropy loss is used to guide the training of the generated network, and the well-designed loss objective function is optimized while the discrimination network is trained. Compared with other multitrack music generation models, the validity of our model is proved.

Sports competition is one of the most popular programs for many audiences. Tracking the players in sports game videos from broadcasts is a nontrivial challenge for computer vision researchers. In sports videos, the direction of an athlete’s movement changes quickly and unpredictably. Mutual occlusion between athletes is also more frequent in team competitions. However, the rich temporal contexts among the adjacent frames have been excluded from consideration. To address this dilemma, we propose an online transformer-based learnable framework in an end-to-end fashion. We use a transformer architecture to extract the temporal contexts between the successive frames and add them to the network training, which is robust to occlusion and complex direction changes in multiplayer tracking. We demonstrate the effectiveness of our method on three sports video datasets by comparing them with recently advanced multiplayer trackers.

The leachate from municipal solid waste transfer stations has a complex composition of pollutants, contains high concentrations of organic matter, and produces odors. The anaerobic digestion of leachate generates excessive volatile organic acids (VFAs), acidifying the digestate and destabilizing or even collapsing the anaerobic process. To solve these issues, we set up a facultative anaerobic system with air exposure and an obligate anaerobic system without air exposure to explore the impact of anaerobic degree on intermediate accumulation and anaerobic process stability. When the organic loading raised from 0.6 to 6.0 kg COD/(m3·d), VFA accumulation in the facultative system peaked at 3.30 g COD/L, and the chemical oxygen demand (COD) removal rate dropped from 95% to 60%. By contrast, the obligate system remained stable, with VFA concentrations below 0.50 g COD/L and COD removal rates between 85% and 99%. Microbial sequencing shows that VFA-oxidizing bacteria enhanced VFA degradation, such as Syntrophomonas and Smithella, which increased from 4.62% and 0.76% in the facultative system to 17.64% and 0.88% in the obligate system, respectively. Coenzyme F420 concentration as an indicator of methanogenic activity was 50% higher in the obligate system. Therefore, an obligate anaerobic system is promising to alleviate acidification for stable anaerobic digestion of leachate.

Background To compare the clinical efficacy of conservative treatment and percutaneous vertebroplasty for the treatment of osteoporotic vertebral compression fracture bearing homogenous hyperintensity signals on magnetic resonance imaging and explore the value of homogenous hyperintensity signal in decision making for osteoporotic vertebral compression fracture treatment.Methods From January 2016 to December 2018, we retrospectively analyzed the radiographic and clinical data of 114 patients with osteoporotic vertebral compression fracture bearing homogenous hyperintensity signals on magnetic resonance imaging. The patients were divided into a percutaneous vertebroplasty group (60 cases) and a conservative treatment group (54 cases). The visual analog scale, Oswestry disability index score, Short Form 36 questionnaire score, kyphosis angle, anterior vertebral body height, and bone union rate were compared between the two groups.Results There were no significant differences in visual analog scale, Oswestry disability index score, and Short Form 36 questionnaire score between the two groups at the three-month and one-year follow-ups (P > 0.05). All 60 patients in the percutaneous vertebroplasty group achieved bone union at the one-year follow-up at a rate of 100%. In the conservative treatment group, one patient did not achieve bone union, and the bone union rate was 98.1%. There was no significant difference in the bone union rate between the two groups (P > 0.05).Conclusions For patients with a homogenous hyperintensity signal, percutaneous vertebroplasty had equivalent efficacy to the conservative treatment at the long-term follow-up. Both percutaneous vertebroplasty and conservative treatment can achieve satisfactory results.

Manganese (Mn) is an essential microelement for broiler breeding and its deficiency causes tibial dyschondroplasia (TD). Tibial growth plate (TGP) development and metaphyseal vascularization are crucial for tibia growth in fast-growing broiler chickens, but their roles in Mn deficiency-induced TD in chicks remain unclear. This study was designed to clarify this issue. A total of 36 one-day-old broilers were divided into the control group and Mn-deficiency (Mn-D) group, which were fed with a standard diet (60 mg Mn/kg) and Mn deficiency diet (22 mg Mn/kg) for 42 days, respectively. TGP and proximal tibial metaphysis were collected to perform the related assays. This study found that Mn deficiency decreased the tibia length and TGP thickness in the TD model. Also, Mn deficiency increased the irregular and white tibial dyschondroplasia lesions (TDL) region under the TGP, and reduced the expression levels of vascular endothelial growth factor (VEGF) and macrophage migration inhibitory factor (MIF). Combined with histological assessment, it was suggested that Manganese deficiency inhibited angiogenesis in the proximal tibial metaphysis. Meanwhile, Mn deficiency enhanced the expression levels of hypoxia-inducible factor-1 α (HIF-1α), autophagy-related protein 5 (ATG5), and microtubule-associated protein 1 light chain 3 β (LC3-II) in TGP, but decreased the expression level of SQSTM1 (P62), which suggested that autophagy was activated during this process. Collectively, these data indicate that HIF-1α up-regulation and concurrent autophagy activation exert a protective effect against Mn deficiency-induced angiogenesis inhibition, which may provide useful guidance to prevent TD in broilers.

Accurate segmentation of cervical nuclei is an essential step in the early diagnosis of cervical cancer. Still, there are few studies on the segmentation of clustered nuclei in clusters of cells. Because of the complexities of high cell overlap, blurred nuclei boundaries, and clustered cells, the accurate segmentation of clustered nuclei remains a pressing challenge. In this paper, we purposefully propose a GCP-Net deep learning network to handle the challenging cervical cluster cell images. The proposed U-Net-based GCP-Net consists of a pretrained ResNet-34 model as encoder, a Gating Context-aware Pooling (GCP) module, and a modified decoder. The GCP module is the primary building block of the network to improve the quality of feature learning. It allows the GCP-Net to refine details of feature maps leveraging multiscale context gating and Global Context Attention for the spatial and texture dependencies. The decoder block including Global Context Attention- (GCA-) Residual Block helps build long-range dependencies and global context interaction in the decoder to refine the predicted masks. We conducted extensive comparative experiments with seven existing models on our ClusteredCell dataset and three typical medical image datasets, respectively. The experimental results showed that the GCP-Net obtained promising results on three evaluation metrics AJI, Dice, and PQ, demonstrating the superiorities and generalizability of our GCP-Net for automatic medical image segmentation in comparison with some SOAT baselines.

Knowledge graph (KG) contains a large number of real-world knowledge and has become an invaluable aid to assist the application of artificial intelligence. Knowledge graph completion (KGC) is the task to complete the missing triple in KG database. Our goal in this study is to enhance the performance of KGC tasks based on CNN model. To do this, we first investigated the effect of adding multiple filters of different shapes into the pioneer model. The obscure improvement leads us to seek other approaches. Our second proposed model, termed DP-ConvKB, which is a deep convolution-neural-network-based model, outperforms state-of-the-art models on several metrics. Our study provides supporting evidence that, by cooperating deep pyramid network structure into models, it can significantly improve the KGC performances.

Bone loss occurs in astronauts during long-term space flight, but the mechanisms are still unclear. We previously showed that advanced glycation end products (AGEs) were involved in microgravity-induced osteoporosis. Here, we investigated the improvement effects of blocking AGEs formation on microgravity-induced bone loss by using the AGEs formation inhibitor, irbesartan. To achieve this objective, we used a tail-suspended (TS) rat model to simulate microgravity and treated the TS rats with 50 mg/kg/day irbesartan, as well as the fluorochrome biomarkers injected into rats to label dynamic bone formation. To assess the accumulation of AGEs, pentosidine (PEN), non-enzymatic cross-links (NE−xLR), and fluorescent AGEs (fAGEs) were identified in the bone; 8-hydroxydeoxyguanosine (8-OHdG) was analyzed for the reactive oxygen species (ROS) level in the bone. Meanwhile, bone mechanical properties, bone microstructure, and dynamic bone histomorphometry were tested for bone quality assessment, and Osterix and TRAP were immunofluorescences stained for the activities of osteoblastic and osteoclastic cells. Results showed AGEs increased significantly and 8-OHdG expression in bone showed an upward trend in TS rat hindlimbs. The bone quality (bone microstructure and mechanical properties) and bone formation process (dynamic bone formation and osteoblastic cells activities) were inhibited after tail-suspension, and showed a correlation with AGEs, suggesting the elevated AGEs contributed to the disused bone loss. After being treated with irbesartan, the increased AGEs and 8-OHdG expression were significantly inhibited, suggesting irbesartan may reduce ROS to inhibit dicarbonyl compounds, thus suppressing AGEs production after tail-suspension. The inhibition of AGEs can partially alter the bone remodeling process and improve bone quality. Both AGEs accumulation and bone alterations almost occurred in trabecular bone but not in cortical bone, suggesting AGEs effects on bone remodeling under microgravity are dependent on the biological milieu.

Epidermal growth factor EGFR is an important target for non-small cell lung (NSCL) cancer, and inhibitors of AKT protein has been used in many cancer treatments including NSCL cancer. Therefore, screening small molecular inhibitors targeting both EGFR and AKT can help for cancer treatment. In this study, we screened Traditional Chinese Medicine on Immune-Oncology (TCMIO) database for potential natural product inhibitors that can target both EGFR and AKT using ligand-based pharmacophore model, molecular docking, and MD simulations methods. The human endogenous database HMDB was also screened. It was found that TCMIO89212, TCMIO90156 and TCMIO98874 from the TCMIO database had large binding free energies with EGFR and AKT. In the HMDB database, kinetin-7-N-glucoside was found to have ability to bind to EGFR and AKT. These results may provide valuable information for further experimental studies.

Deep learning neural networks based on the manual design for image classification tasks usually require a large amount of a priori knowledge and experience from experts; thus, research on designing neural network architectures automatically has been widely performed. The neural architecture search (NAS) method based on the differentiable architecture search (DARTS) ignores the interrelationships within the searched network architecture cells. The optional operations in the architecture search space lack diversity, and the large parametric and non-parametric operations in the search space make the search process inefficient. We propose a NAS method based on a dual attention mechanism (DAM-DARTS). An improved attention mechanism module is introduced to the cell of the network architecture to deepen the interrelationships between the important layers within the architecture by enhancing the attention between them, which improves the accuracy of the architecture and reduces the architecture search time. We also propose a more efficient architecture search space by adding attention operations to increase the complex diversity of the searched network architectures and reduce the computational cost consumed in the search process by reducing non-parametric operations. Based on this, we further analyze the impact of changing some operations in the architecture search space on the accuracy of the architectures. Through extensive experiments on several open datasets, we demonstrate the effectiveness of the proposed search strategy, which is highly competitive with other existing neural network architecture search methods.

Based on the excellent performances of nanocrystalline cellulose, sodium alginate, or K-carrageenan in Pb2+ adsorption, nanocrystalline cellulose/sodium alginate/K-carrageenan composite hydrogel beads were prepared to adsorb Pb(II) from aqueous solutions. The objective of this study was to demonstrate the excellent potential of the composite hydrogel beads for heavy metal ion adsorption. We successfully prepared ecofriendly Fe-modified nanocrystalline cellulose/sodium alginate/K-carrageenan composite hydrogel beads and characterized them. The structure and adsorption mechanism were investigated using scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy, and the optimal adsorption conditions were determined. The tricomponent hydrogel beads were robust and exhibited improved adsorption capacity for Pb2+ and good reusability. The adsorption results could be fitted well with a pseudo-second-order kinetic model and the Langmuir adsorption model. The maximum adsorption capacity obtained by fitting was 351.04 mg g−1. Recycling experiments revealed that the adsorption capacity of the adsorbent remained high after five cycles of reuse.

The production of traditional Peking opera facial masks often relies on hand painting by experienced painters, which restricts the inheritance and development of this intangible cultural heritage. Current research mainly focuses on the digital reconstruction and storage of existing Peking opera facial masks, while high-quality facial mask generation technology is still in an infancy stage. In this paper, different deep learning frameworks are improved for learning features of Peking opera facial masks and generating new masks, which can effectively promote the creative application of Peking opera facial masks. First, using different data enhancement methods, an improved Style Generative Adversarial Network-2 (StyleGAN2) can learn implicit and explicit features of Peking opera facial masks and automatically generate new facial masks. In addition, an image translation framework for joint cross-domain communication under weak supervision is used to translate face sketches and color reference maps to an intermediate feature domain, and then synthesize new facial masks through an image generation network. The experimental results show that the generated Peking opera facial masks have good local randomness and excellent visual quality.

Background We present a case of pelvic paraganglioma that presented with heart failure as the primary symptom. Case presentation A 35-year-old man was admitted to hospital due to heart failure. Contrast-enhanced pelvic CT showed mass shadows in the posterior wall of the bladder and multiple enlarged lymph nodes in the retroperitoneal area. Ultrasound-guided puncture was performed, and the pathologic diagnosis was extra-adrenal paraganglioma. The patient refused any chemotherapy and died within six months of diagnosis. Conclusion The possibility of neuroendocrine-related tumors, for example paragangliomas, should be considered in young patients with heart failure, especially those with concomitant hypertension and diabetes.

In recent years, there has been a national craze for metaverse concerts. However, existing meta-universe concert efforts often focus on immersive visual experiences and lack consideration of the musical and aural experience. But for concerts, it is the beautiful music and the immersive listening experience that deserve the most attention. Therefore, enhancing intelligent and immersive musical experiences is essential for the further development of the metaverse. With this in mind, we propose a metaverse concert generation framework — from intelligent music generation to stereo conversion and sound field design for virtual concert stages. First, combining the ideas of reinforcement learning and value functions, the Transformer-XL music generation network is improved and used in training all the music in the POP909 dataset. Experiments show that both improved algorithms have advantages over the original method in terms of objective evaluation and subjective evaluation metrics. In addition, this paper validates a neural rendering method that can be used to generate spatial audio based on a binaural-integrated neural network with a fully convolutional technique. And the purely data-driven end-to-end model performs to be more reliable compared with traditional spatial audio generation methods such as HRTF. Finally, we propose a metadata-based audio rendering algorithm to simulate real-world acoustic environments.

Manganese (Mn) is a crucial trace element for poultry nutrition, and its deficiency compromises tibial cartilage development, leading to perosis and a higher incidence of slipped tendon. Tibial dyschondroplasia (TD) is a metabolic cartilage disease characterized by disruption of endochondral bone formation, which is closely related to extracellular matrix (ECM) degradation, in which Mn deficiency plays an important role. Previous studies have confirmed the role of matrix metalloproteinases (MMPs) in the pathogenesis of TD, but whether dysregulated ECM degradation and MMP expression profiles in growth plate are involved in Mn deficiency-induced avian TD has not been fully elucidated yet. Thus, this study was conducted to clarify these issues. Firstly, we successfully established TD model induced by Mn deficiency in broiler chicks. Mn deficiency decreased the number of chondrocytes, contents of proteoglycan, and type II collagen in tibial growth plate, demonstrating the tibial growth plate damage with enhanced ECM degradation. Also, Mn deficiency inhibited the Nrf2 signaling pathway and enhanced the protein levels of NLRP3, active caspase-1, and active IL-1β in tibial growth plate, indicating the oxidative stress and inflammatory response in Mn deficiency-induced TD. Additionally, upregulated expression levels of MMPs (MMP1, 9, and 13) were observed in tibial growth plate of Mn deficiency group. In summary, these findings suggest that Mn deficiency-enhanced ECM degradation is involved in avian TD, which may be correlated with oxidative stress, inflammatory response, and upregulation of MMPs.

Surface modification of cellulose nanocrystals (CNC) is essential for improving their reactivity and adsorption capacity. Oxidation, as a conventional modification method of CNC, has strong reaction conditions, which may partially destroy the structure of CNCs. Herein, we propose a mild cellulose modification method, in which diethylenetriaminepentaacetic acid (DPTA) was grafted onto CNC with an aminosilane coupling agent. To facilitate the enrichment and recovery of adsorbents, we prepared magnetic CNC before grafting DPTA, and finally obtained magnetic carboxylic functionalized CNC (MCNC-DPTA). The effects of the reaction parameters on the adsorption process were systematically studied by transmission electron microscopy, X-ray diffraction, Vibration sample magnetometry, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Additionally, the effects of the solution pH, the initial concentration of Pb, and the adsorption time on the adsorption properties of the materials were evaluated. Furthermore, the structure, morphology, and thermal properties of the solution were systematically studied. After 6 cycle tests, the adsorption amount of Pb(II) by MCNC-DPTA was only reduced by 7%. These results show that MCNC-DPTA is an environment-friendly adsorption material with an excellent Pb(II) removal effect.

Osteocytes are extremely sensitive to mechanical loading and govern bone remodeling process. Advanced glycation end products (AGEs) have the capacity to induce osteocyte apoptosis. In order to investigate the effects of AGEs on the mechanosensitivity of osteocytes, the osteocytic-like cells (MLO-Y4) were treated with low (50 μg/ml) and high (400 μg/ml) concentrations of AGEs for 1day and exposed to 15 dyne/cm2 of fluid shear stress. Then the F-actin cytoskeleton, prostaglandin E2(PGE2), Nitric oxide (NO), the Wnt/β-catenin signaling pathway activity mRNA expressions were detected for osteocytes mechanical response changes; osteocalcin (OCN) and receptor activator of nuclear factor-kappa B ligand (RANKL)/osteoprotegerin (OPG) were detected for the regulation on bone remodeling function of osteocytes. The results showed that AGEs accumulation inhibited the sense of osteocytes to external mechincal loading, promoted shear-induced NO and PGE2 release, suppressed the mechanosensitivity of Wnt/β-catenin signaling pathway, and furthermore promoted OCN and RANKL/OPG mRNA expressions. These indicated AGEs had an adverse impact on the mechanosensitivity of osteocytes, and led to a negative effect on their regulation of bone remodeling process under mechanical stimulation. This work provides a new perspective to interpret the alteration mechanism of osteocytes mechanosensitivity and provides a novel clue for exploring the mechanism of osteoporosis.

Objective. Although prolactin (PRL) is known to affect food intake, weight gain, and insulin resistance, its effects on lipid metabolism and underlying mechanisms remain underinvestigated. This study aimed to investigate the effects of PRL and its receptor (PRLR) on fat metabolism in regulating the JAK2/STAT5 signaling pathway. Methods. SW872 adipocytes were incubated with oleic acid to establish an insulin resistance (IR) model. Western blot was used to detect the expression of PRLR, JAK2, p-JAK2, STAT5, and p-STAT5. Triglyceride (TG) mass was detected by chemical colorimetry methods. Results. Fat droplets in the high-dose and medium-dose PRL groups were significantly higher than in the IR model group. TG mass in the cells was increased significantly compared with the model group. Compared with the control group, the expression of PRLR, p-JAK2, and p-STAT5 were significantly decreased in the IR model group when PRL was intervened for 24 h and 48 h. The expression of PRLR, p-JAK2, and p-STAT5 in the high-dose PRL intervention group increased significantly compared with the model group. The PRLR overexpressing group had significantly increased TG content and PRLR, and JAK2, p-JAK2, STAT5, and p-STAT5 levels compared with the IR model. Conclusion. PRL and PRLR are related to fat metabolism, and the PRL/PRLR signaling pathway can promote insulin resistance by activating the JAK2/STAT5 signaling pathway and increasing the deposition of TGs.

The marine talent cultivation and output in higher vocational colleges is an important support to build a strong maritime country and ensure the steady development of the shipping business industry. Vocational colleges should ensure effective career preparation and career guidance education for their students, and train them to acquire the professional abilities to work and adapt effectively and quickly in the future. Some studies show that many crew members experience a decline in job satisfaction, a low sense of achievement, and a series of negative subjective career feelings. Even more, some crew members have poor work performance or unsuccessful career development behaviors such as career change or resignation. This study examined the causes and influencing factors of these circumstances and might be a reference for schools to strengthen the quality of their training programs in the future. In-depth interviews with 12 vocational marine navigation college graduates were conducted, and grounded theory was used to code and analyze the collected interview information. Four types of influencing factors were identified: adaptation preparation, career adaptability, adaptation action, and the situational factor. The adaptation preparation factor could be categorized into psychology, determination, lack of certificates, and simple work; the career adaptability factor could be categorized into boring work, busyness, a big gap between expectations and reality, danger, promotion difficulty, poor interpersonal relationships, high pressure, and maladaptation to the surroundings; the adaptation action factor could be categorized into passive fatigue, lack of training, competition, confidence, and planning; while the situational factor could be categorized into the impact of the epidemic, low social status, lack of support from family, and advantages of living on land. To help the marine navigation students better adapt to their jobs and avoid subjective career unsuccessfulness, higher vocational colleges need to strengthen students’ mental health education, consolidate knowledge and skills training, encourage students to obtain more vocational competency certificates, enhance their interpersonal communication skills, do effective career planning, pay attention to physical exercise and safety awareness training, and adopt other career management and counseling suggestions.

The microscale combustion calorimeter (MCC) is considered to be the most commonly used small-scale fire experiment in material research. It was developed by Richard E. Lyon and Richard Walters from the Federal Aviation Administration and has existed for over two decades. During this period, the apparatus has been used to obtain combustion properties for a wide range of materials as well as screening flame retardants for the production of fire-resistant materials. MCC separately simulates the pyrolysis and combustion stages of a burning process in a non-flaming test and uniquely measures the heat release capacity. Since its development, several significant modifications have been made in the apparatus to rectify some of the sources of error. This research reviews the literature on microscale combustion calorimetry. It covers the principles of operation applications and limitations, prediction methods and mathematical models for estimation as well as the modifications made in the design. Furthermore, the relationship between MCC parameters and measurement from other fire experiments are outlined. Lastly, the experimental methods designed on the basis of microscale combustion calorimetry have been briefly described.

Plant laccases are copper-containing glycoproteins oxidizing monolignol, which is a key regulator for lignin polymerization and deposition in plant cell walls. In plants, the LAC gene family has been identified and functionally characterized in Arabidopsis, rice, and other plant species. Whereas, no systematic analysis of LAC genes was explored in pear (Pyrus bretschneideri), especially their biological roles in stress responses. In this study, a total of 40 P. bretschneideri LACs (PbLACs) were identified from the pear genome, among which 32 PbLACs members were distributed on 14 chromosomes, and 8 PbLACs were mapped onto scaffold contigs. Subsequently, the chromosome localizations, gene structures, conserved domains, gene duplication were analyzed comprehensively and bioinformatically. Phylogenetic analysis demonstrated that the PbLACs were classified into seven groups. Synteny analysis exhibited that whole-genome duplication (WGD)/segmental duplication was essential for the expansion of PbLAC family. In detail, the 26 PbLACs duplicated gene pairs were taken place at the two WGD events. Further, our results showed that purifying selection presented as the primary force to drive the evolution of PbLACs. Notably, the transcriptomic data were used for exploring the biological roles of PbLACs in response to abiotic stresses (cold, drought, and salt) in pear. We found that the expression of certain PbLACs was significantly induced by drought, cold or salt treatments, suggesting that these PbLACs are potentially key genes for further functional characterization in pear in the future. Taken together, our results not only contribute to an enhanced understanding of the evolutional complexity of PbLAC gene family but also provide a good platform for functional studies of PbLAC genes in response to various abiotic stresses.

L Antigen Family Member 3 (LAGE3) is an important RNA modification-related protein. Whereas few studies have interrogated the LAGE3 protein, there is limited data on its role in tumors. Here, we analyzed and profiled the LAGE3 protein in skin cutaneous melanoma (CM) using TCGA, GTEx, or GEO databases. Our data showed an upregulation of LAGE3 in melanoma cell lines compared to normal skin cell lines. Besides, the Kaplan–Meier curves and Cox proportional hazard model revealed that LAGE3 was an independent survival indicator for CM, especially in metastatic CM. Moreover, LAGE3 was negatively associated with multiple immune cell infiltration levels in CM, especially CD8+ T cells in metastatic CM. Taken together, our study suggests that LAGE3 could be a potential prognostic biomarker and might be a potential target for the development of novel CM treatment strategies.

Phosphine–oxazoline (PHOX) ligands are a very important class of privileged ligands in asymmetric catalysis. A series of highly rigid oxa-spiro phosphine–oxazoline (O-SIPHOX) ligands based on O-SPINOL was synthesized efficiently, and their iridium complexes were synthesized by coordination of the O-SIPHOX ligands to [Ir(cod)Cl]2 in the presence of sodium tetrakis-3,5-bis(trifluoromethyl)phenylborate (NaBArF). The cationic iridium complexes showed high reactivity and excellent enantioselectivity in the asymmetric hydrogenation of 1-methylene-tetrahydro-benzo[d]azepin-2-ones (up to 99% yield and up to 99% ee). A key intermediate of the anti-obesity drug lorcaserin could be efficiently synthesized using this protocol.

Since the advent of massive open online courses (MOOC), it has been the focus of educators and learners around the world, however the high dropout rate of MOOC has had a serious negative impact on ...

Software defect prediction (SDP) is a very important way for analyzing software quality and reducing development costs. The data during software lifecycle can be used to predict software defect. Currently, many SDP models have been proposed; however, their performance was not always ideal. In many existing prediction models based on machine learning, the distance metric between samples has significant impact on the performance of the SDP model. In addition, most samples are usually class imbalanced. To solve these issues, in this paper, a novel distance metric learning based on cost-sensitive learning (CSL) is proposed for reducing the impact of class imbalance of samples, which is then applied to the large margin distribution machine (LDM) to substitute the traditional kernel function. Further, the improvement and optimization of LDM based on CSL are also studied, and the improved LDM is used as the SDP model, called as CS-ILDM. Subsequently, the proposed CS-ILDM is applied to five publicly available data sets from the NASA Metrics Data Program repository and its performance is compared to other existing SDP models. The experimental results confirm that the proposed CS-ILDM not only has good prediction performance, but also can reduce the misprediction cost and avoid the impact of class imbalance of samples.

Most of the current works are still limited to dealing with the melody generation containing pitch, rhythm, duration of each note, and pause between notes. This paper proposes a transformer-based model to generate multi-track music including tracks of piano, guitar, and drum, which is abbreviated as MTMG model. The proposed MTMG model is mainly innovated and improved on the basis of transformer. Firstly, the model obtains three target sequences after pairwise learning through learning network. Then, according to these three target sequences, GPT is applied to predict and generate three closely related sequences of instrument tracks. Finally, the three generated instrument tracks are fused to obtain multi-track music pieces containing piano, guitar, and drum. To verify the effectiveness of the proposed model, related experiments are conducted on a pair of comparative subjective and objective evaluation. The encouraging performance of the proposed model over other state-of-the-art models demonstrates its superiority in musical representation.

Automatic music composition could dramatically decrease music production costs, lower the threshold for the non-professionals to compose as well as improve the efficiency of music creation. In this paper, we proposed an intelligent music composition neutral network to automatically generate a specific style of music. The advantage of our model is the innovative structure: we obtained the music sequence through an actor’s long short term memory, then fixed the probability of sequence by a reward-based procedure which serves as feedback to improve the performance of music composition. The music theoretical rule is introduced to constrain the style of generated music. We also utilized a subjective validation in experiment to guarantee the superiority of our model compared with state-of-the-art works.

Image denoising is an important technology for image preprocessing. In recent years, the image denoising technology based on total variation (TV) has been rapidly developed. However, However, although it can preserve image details well, which generates obvious staircase effects. This is due to the traditional TV-based image denoising technology only applies the gradient information and ignored the local variance of the image. In order to suppress staircase effect, in this paper, a novel image denoising approach based on TV model and weighting function is proposed. First, the theory mechanism of staircase effect brought by the traditional TV model is analyzed. Second, the effects of weighting function on edge regions, flat regions, and gradation and detail regions are also analyzed. Third, based on the above analysis, an improved TV model is proposed. Finally, the image denoising approach is implemented by an iterative algorithm. The experimental results show that, compared with various state-of-the-art models denoising models, the proposed image denoising approach can effectively suppress the staircase effect of the traditional TV model in most cases, preserve the image details, and improve the image denoising performance.

Background Since the introduction of HIV self-testing by UNAIDS in 2014, the practice has been extensively implemented around the world. HIV self-testing (HIVST) was developed in China around 2015, and the online purchase of HIVST kits through e-commerce platforms has since become the most important delivery method for self-testing, with advantages such as user-friendliness, speed, and better privacy protection. Objective Understanding the spatiotemporal characteristics of online HIVST kit purchasing behavior and identifying potential impacting factors will help promote the HIV self-testing strategy. Methods The online retail data of HIVST kits from the 2 largest e-commerce platforms in China from 2015 to 2017 were collected for this study. The Bayesian spatiotemporal hierarchical model was used to investigate the spatiotemporal characteristics of online purchased HIVST kits. Ordinary least squares regression was used to identify potential factors associated with online purchase, including GDP per capita, population density, road density, HIV screening laboratory density, and newly diagnosed HIV/AIDS cases per 100,000 persons. The q statistics calculated by Geodetector were used to determine the interactive effect of every 2 factors on the online purchase. Results The online purchase of HIVST kits increased rapidly in China from 2015 to 2017, with annual peak sales in May and December. Five economically superior regions in China, Pearl River Delta, Yangtze River Delta, Chengdu and surrounding areas, Beijing and Tianjin areas, and Shandong Peninsula, showed a comparatively higher spatial preference for online purchased HIVST kits. The GDP per capita (P Conclusions Individuals in better-off areas are more inclined to purchase HIVST kits online. In addition to economic status, the severity of the HIV epidemic is also a factor influencing the online purchase of HIVST kits.

IntroductionSkip metastasis, referred to as lymph node metastases to the lateral neck compartment without involvement of the central compartment, is generally unpredictable in papillary thyroid carcinoma (PTC). This study aims to establish an effective predictive model for skip metastasis in PTC.Meterials and MethodsRetrospective analysis was performed of clinical samples from 18192 patients diagnosed with thyroid cancer between 2016 to 2020. The First Affiliated Hospital of Wenzhou Medical University. The lateral lymph node metastasis was occureed in the training set (630 PTC patients) and validation set (189 PTC patients). The univariate and multivariate analyses were performed to detect the predictors of skip metastasis and the support vector machine (SVM) was used to establish a model to predict skip metastasis.ResultsThe rate of skip metastasis was 13.3% (84/631). Tumor size (≤10 mm), upper location, Hashimoto’s thyroiditis, extrathyroidal extension, absence of BRAFV600E mutation, and less number of central lymph node dissection were considered as independent predictors of skip metastasis in PTC. For the training set, these predictors performed with 91.7% accuracy, 86.4% sensitivity, 92.2% specificity, 45.2% positive predictive value (PPV), and 98.9% negative predictive value (NPV) in the model. Meanwhile, these predictors showed 91.5% accuracy,71.4% sensitivity, 93.1% specificity, 45.5% PPV, and 97.6% NPV in validation set.ConclusionThis study screened the predictors of the skip lateral lymph node metastasis and to establish an effective and economic predictive model for skip metastasis in PTC. The model can accurately distinguish the skip metastasis in PTC using a simple and affordable method, which may have potential for daily clinical application in the future.

Papillary thyroid cancer (PTC) is the most common malignancy of the endocrine system, with an increase in incidence frequency. Major vault protein (MVP) is the main structural protein of the vault complex that has already been investigated in specific cancers. Yet the underlying biological functions and molecular mechanisms of MVP in PTC still remain considerably uncharacterized. Comprehensive analyses are predicated on several public datasets and local RNA-Seq cohort. Clinically, we found that MVP was upregulated in human PTC than in non-cancerous thyroid tissue and was correlated with vital clinicopathological parameters in PTC patients. MVP expression was associated with BRAFV600E, RAS, TERT, and RET status, and it was correlated with worse progression-free survival in PTC patients. Functionally, enrichment analysis provided new clues for the close relationship between MVP with cancer-related signaling pathways and the immune microenvironment in PTC. In PTC with high MVP expression, we found CD8+ T cells, regulatory T cells, and follicular helper T cells have a higher infiltration level. Intriguingly, MVP expression was positively correlated with multiple distinct phases of the anti-cancer immunity cycle. MVP knockdown significantly suppressed cell viability and colony formation, and promoted apoptosis. In addition, downregulated MVP markedly inhibited the migration and invasion potential of PTC cells. The rescue experiments showed that MVP could reverse the level of cell survival and migration. Mechanistically, MVP exerts its oncogenic function in PTC cells through activating PI3K/AKT/mTOR and MAPK/ERK pathways. These results point out that MVP is a reliable biomarker related to the immune microenvironment and provide a basis for elucidating the oncogenic roles of MVP in PTC progression.

Manganese (Mn) is an essential microelement for broiler breeding and its deficiency causes tibial dyschondroplasia (TD). Tibial growth plate (TGP) development and metaphyseal vascularization are crucial for tibia growth in fast-growing broiler chickens, but their roles in Mn deficiency-induced TD in chicks remains unclear. This study was designed to clarify this issue. A total of 36 one-day-old broilers were divided into the control group and Mn-deficiency (Mn-D) group, which were fed with a standard diet (60 mg Mn/kg) and Mn deficiency diet (22 mg Mn/kg) for 42 days, respectively. TGP and proximal tibial metaphysis were collected to perform the related assays. First, Mn deficiency decreased the tibia length and TGP thickness in TD model. Mn deficiency reduced the number of blood vessels in proximal tibial metaphysis by histological analysis. Also, Mn deficiency decreased the mRNA and protein expression levels of vascular endothelial growth factor (VEGF) and macrophage migration inhibitory factor (MIF) in TGP. Moreover, up-regulation of hypoxia-inducible factor-1 alpha (HIF-1α) at both mRNA and protein levels was found in TGP of Mn-D group, suggesting the antagonistic role of HIF-1α against angiogenesis inhibition. Additionally, Mn deficiency enhanced the autophagy related 5 (ATG5) and microtubule associated protein 1 light chain 3 beta (LC3-II) expression levels, but decreased the SQSTM1 (p62) expression levels in TGP, suggesting autophagy activation in this process. Collectively, these data indicate that HIF-1α up-regulation and concurrent autophagy activation exert the protective effect against Mn deficiency-induced angiogenesis inhibition, which may provide a useful guidance to prevent TD in broilers.

Human immunodeficiency virus 1 (HIV-1) attacks the immune system, making people susceptible to various diseases, thus increasing their risk of death. Comprehensive detection of major HIV-1 strains circulating in China is vital for effective HIV-1 infection prevention and treatment. HIV-1 nucleic acid detection is considered effective for HIV-1 diagnosis since traditional immunological testing may fail to detect HIV-1 infection during the window period. This work demonstrates a one-pot two-stage amplification assay (RT-RAP), a combination of reverse transcription recombinase (RT- RAA), and quantitative real-time polymerase chain reaction (qRT-PCR). The turn-around time of the assay is only 50 min and can be performed with commonly available laboratory equipment, the qPCR devices. The RT-RAP assay could detect approximately 5 and 14 copies/reaction of HIV-1 DNA and RNA using recombinant plasmids and standard reference strains, respectively. Additionally, we found that the clinical performance of RT-RAP (detected 169 samples out of 170 specimens) was consistent with that of qRT-PCR. The sensitivity and specificity of RT-RAP were 100.00% (99/99) and 98.59% (70/71), respectively, while its positive and negative predictive values were 99.00% (99/100) and 100.00% (70/70), respectively. The total coincidence rate of the RT-RAP was 99.41% (169/170), with a kappa value of 0.988 (p < 0.05). We demonstrated that RT-RAP could rapidly detect the common HIV-1 subtypes commonly circulating in China with comparable sensitivity and specificity to qRT-PCR.

Whether telbivudine (LdT) treatment to pregnant women with hepatitis B surface antigen (HBsAg) affects infant immune response to hepatitis B vaccine (HepB) has not been investigated. A total of 127 HBsAg positive mothers and their neonates were enrolled and followed up at 11-13 months. Mothers took LdT (LdT group) or did not receive antiviral therapy (control group). Infant anti-HBs, immune cells and cytokines were measured after HepB was administered according to 0-1-6 procedure. We performed a 1:3 propensity score matching (PSM). Immune indexes in the two groups were compared. Baseline characteristics of mother-baby pairs were comparable in LdT group and control group. Infant anti-HBs geometric mean concentration (GMC) did not differ significantly between the two groups [767.70 (745.35) vs. 711.90 (819.60)

Additional file 2: Statistical analysis of metabolomic data by different methods.