32 research outputs found

    Smoothing algorithms for nonsmooth and nonconvex minimization over the stiefel manifold

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    We consider a class of nonsmooth and nonconvex optimization problems over the Stiefel manifold where the objective function is the summation of a nonconvex smooth function and a nonsmooth Lipschitz continuous convex function composed with an linear mapping. We propose three numerical algorithms for solving this problem, by combining smoothing methods and some existing algorithms for smooth optimization over the Stiefel manifold. In particular, we approximate the aforementioned nonsmooth convex function by its Moreau envelope in our smoothing methods, and prove that the Moreau envelope has many favorable properties. Thanks to this and the scheme for updating the smoothing parameter, we show that any accumulation point of the solution sequence generated by the proposed algorithms is a stationary point of the original optimization problem. Numerical experiments on building graph Fourier basis are conducted to demonstrate the efficiency of the proposed algorithms.Comment: 22 page

    Pharmacological profile of Xanthohumol, a Prenylated Flavonoid from Hops (Humulus lupulus)

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    The female inflorescences of hops (Humulus lupulus L.), a well-known bittering agent used in the brewing industry, have long been used in traditional medicines. Xanthohumol (XN) is one of the bioactive substances contributing to its medical applications. Among foodstuffs XN is found primarily in beer and its natural occurrence is surveyed. In recent years, XN has received much attention for its biological effects. The present review describes the pharmacological aspects of XN and summarizes the most interesting findings obtained in the preclinical research related to this compound, including the pharmacological activity, the pharmacokinetics, and the safety of XN. Furthermore, the potential use of XN as a food additive considering its many positive biological effects is discussed

    The Impact of AI’s Response Method on Service Recovery Satisfaction in the Context of Service Failure

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    In order to perpetuate service sustainability and promote sustainable growth in the service sector, it is important to resolve service failures. AI technology is being applied to service jobs in more and more industries, but AI will inevitably fail while providing service. How to carry out service recovery and obtain the understanding and forgiveness of customers is a problem that urgently needs solving in the practice and research of AI services. The purpose of this study was to explore the artificial intelligence remediation mechanism in the context of service failure and to explore the remedial utility of AI’s self-deprecating humor responses. The study conducted data collection through three experiments to test our hypotheses: study 1 verified the main effect of self-deprecating humor responses and the mediating effect of perceived sincerity and perceived intelligence; study 2 verified the moderated effect of the sense of power; and study 3 verified the moderated effect of failure experience. The experimental results show that, in the context of AI for service recovery, self-deprecating humor responses can improve customers’ willingness to tolerate failure, with perceived intelligence and perceived sincerity found to play a mediating role in this. The sense of power also plays a moderating role by affecting perceived sincerity, and failure experience has a moderate effect by affecting perceived intelligence. The theoretical contribution of the article is to introduce the perspective of AI’s self-deprecating humor service recovery, which complements theoretical research in the field of AI services. The management significance of the article is to provide new AI communication strategies and practical suggestions for enterprises and technical personnel

    Characterization of the complete mitochondrial genome of the Pohlia nutans M211 from Antarctica

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    The complete mitochondrial genome of Pohlia nutans M211, sequenced using Illumina NovaSeq PE150, was 99864 bp in length. It encoded 65 genes, comprising 38 protein-coding genes, 24 tRNA genes and 3 ribosomal RNA genes. For these 38 PCGs, the most common start codon was ATG and the most common termination codon was TAA. The total GC content was 36.91% while the composition of A + T was 60.39%. Phylogenomic analysis indicated that P. nutans M211 was closely related to Mielichhoferia elongate

    ARDformer: Agroforestry Road Detection for Autonomous Driving Using Hierarchical Transformer

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    Road detection is a crucial part of the autonomous driving system, and semantic segmentation is used as the default method for this kind of task. However, the descriptive categories of agroforestry are not directly definable and constrain the semantic segmentation-based method for road detection. This paper proposes a novel road detection approach to overcome the problem mentioned above. Specifically, a novel two-stage method for road detection in an agroforestry environment, namely ARDformer. First, a transformer-based hierarchical feature aggregation network is used for semantic segmentation. After the segmentation network generates the scene mask, the edge extraction algorithm extracts the trail’s edge. It then calculates the periphery of the trail to surround the area where the trail and grass are located. The proposed method is tested on the public agroforestry dataset, and experimental results show that the intersection over union is approximately 0.82, which significantly outperforms the baseline. Moreover, ARDformer is also effective in a real agroforestry environment

    The complete chloroplast genome of Spartina alterniflora

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    Spartina alterniflora (also named as Sporobolus alterniflorus) grows in coastal salt marshes area, which has important economic value in coastal natural wetlands. In the process of this research, the whole chloroplast genome sequence of Spartina alterniflora was recovered by Illumina sequencing. The complete genome was 135,560 bp in length with 38.45% GC content which was a circular genome containing a large single-copy region (LSC, 80,828 bp), a small single-copy region (SSC, 12,714 bp) and a pair of inverted repeat regions (IRs, 42,018 bp). Totally, it encodes 130 genes, including 84 protein-coding genes, 38 tRNAs, and 8 rRNAs. Phylogenetic analysis indicated that Spartina alterniflora was closely related to Sporobolus maritimus

    TMBPF-induced neurotoxicity and oxidative stress in zebrafish larvae: impacts on central nervous system development and dopamine neurons

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    Bisphenol A (BPA), a common bisphenol molecule, is well known in the environment as an endocrine disruptor. Furthermore, BPs (BPA, BPS, BPF, and BPAF) have been shown in recent years to be neurotoxic to zebrafish. Tetramethyl bisphenol F (TMBPF) has recently been introduced as a substitute for bisphenol A (BPA) in various industries, including plastics and food contact coatings. However, a growing number of studies have demonstrated that the toxicity of some BPA substitutes is similar to or even stronger than BPA, posing potential harm to human health and the environment. In this study, we used zebrafish larvae as a model to investigate the neurodevelopmental effects of TMBPF at different concentrations (0, 0.25, 0.5, 1, 2, 4 and 8 mg/L). Our results showed that exposure to TMBPF at concentrations higher than 4 mg/L for 72 h post-fertilization (hpf) resulted in zebrafish mortality, whereas exposure to 2 mg/L for 144 hpf caused deformities. Furthermore, TMBPF exposure inhibited the development of the central nervous system, motor nerves, and dopamine neurons in zebrafish. Real-time polymerase chain reaction (PCR) analysis revealed that TMBPF exposure significantly down-regulated the expression of oxidative stress-related genes (Cu/Zn-SOD, Mn-SOD, and CAT) and neurodevelopmental genes (mbp, gafp, and syn2a), while up-regulated the expression of dopamine-related genes (th1, th2, and dat). Notably, treatment with the antioxidant N-acetylcysteine (NAC) alleviated TMBPF-induced toxicity. NAC can regulate the expression of genes related to oxidative stress, neurodevelopment and dopamine development, and make the nerve development of zebrafish normal. Overall, our research suggested that TMBPF may disrupt the development of the early central nervous system and dopamine neurons, leading to abnormal motor behavior in zebrafish larvae. These results highlight the potential risks associated with the use of TMBPF in various industries and the importance to evaluate its potential risks to human health and the environment

    The complete mitochondrial genome of Sporobolus alterniflorus (loisel.) P.M. Peterson & Saarela (Poaceae) and phylogenetic analysis

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    The complete mitochondrial genome of Sporobolus alterniflorus was a circular molecule of 566,328 bp in length and encoded 64 genes, including 35 protein-coding genes, 24 tRNA genes, and 5 rRNA genes. The most common initiated codon was ATG and the most common termination codon was CAT. The overall A + T content was 55.96%. The phylogenomic analysis revealed that Sporobolus alterniflorus have a closest phylogenetic relationship with Sorghum bicolor

    Doxorubicin-loading core-shell pectin nanocell: A novel nanovehicle for anticancer agent delivery with multidrug resistance reversal.

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    Tumor is a prevalent great threat to public health worldwide and multidrug resistance (MDR) of tumor is a leading cause of chemotherapy failure. Nanomedicine has shown prospects in overcoming the problem. Doxorubicin (DOX), a broad-spectrum anticancer drug, showed limited efficacy due to MDR. Herein, a doxorubicin containing pectin nanocell (DOX-PEC-NC) of core-shell structure, a pectin nanoparticle encapsulated with liposome-like membrane was developed. The DOX-PEC-NC, spheroid in shape and sized around 150 nm, exerted better sustained release behavior than doxorubicin loading pectin nanoparticle (DOX-PEC-NP) or liposome (DOX-LIP). In vitro anticancer study showed marked accumulation of doxorubicin in different tumor cells as well as reversal of MDR in HepG2/ADR cells and MCF-7/ADR cells caused by treatment of DOX-PEC-NC. In H22 tumor-bearing mice, DOX-PEC-NC showed higher anticancer efficacy and lower toxicity than doxorubicin. DOX-PEC-NC can improve anticancer activity and reduce side effect of doxorubicin due to increased intracellular accumulation and reversal of MDR in tumor cells, which may be a promising nanoscale drug delivery vehicle for chemotherapeutic agents
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