57 research outputs found

    Novel Modelling Strategies for High-frequency Stock Trading Data

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    Full electronic automation in stock exchanges has recently become popular, generating high-frequency intraday data and motivating the development of near real-time price forecasting methods. Machine learning algorithms are widely applied to mid-price stock predictions. Processing raw data as inputs for prediction models (e.g., data thinning and feature engineering) can primarily affect the performance of the prediction methods. However, researchers rarely discuss this topic. This motivated us to propose three novel modelling strategies for processing raw data. We illustrate how our novel modelling strategies improve forecasting performance by analyzing high-frequency data of the Dow Jones 30 component stocks. In these experiments, our strategies often lead to statistically significant improvement in predictions. The three strategies improve the F1 scores of the SVM models by 0.056, 0.087, and 0.016, respectively.Comment: 28 pages, 5 tables, 5 figure

    PB-ACR: Node Payload Balanced Ant Colony Optimal Cooperative Routing for Multi-Hop Underwater Acoustic Sensor Networks

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    For a given source-destination pair in multi-hop underwater acoustic sensor networks (UASNs), an optimal route is the one with the lowest energy consumptions that usually consists of the same relay nodes even under different transmission tasks. However, this will lead to the unbalanced payload of the relay nodes in the multi-hop UASNs and accelerate the loss of the working ability for the entire system. In this paper, we propose a node payload balanced ant colony optimal cooperative routing (PB-ACR) protocol for multi-hop UASNs, through combining the ant colony algorithm and cooperative transmission. The proposed PB-ACR protocol is a relay node energy consumption balanced scheme, which considers both data priority and residual energy of each relay node, aiming to reduce the occurrence of energy holes and thereby prolong the lifetime of the entire UASNs. We compare the proposed PB-ACR protocol with the existing ant colony algorithm routing (ACAR) protocol to verify its performances in multi-hop UASNs, in terms of network throughput, energy consumption, and algorithm complexity. The simulation results show that the proposed PB-ACR protocol can effectively balance the energy consumption of underwater sensor nodes and hence prolong the network lifetime

    Springback of hot stamping and die quenching with ultra-high-strength boron steel

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    Hot bending and die quenching for U-shaped parts with ultra-high-strength boron steel were experimented and simulated to study the effect of die geometric parameters on springback and its mechanism. The results indicate that through hot contact bending and die quenching, bending parts with higher strength than that of cold stamping can be achieved, the tensile strength of which can reach 1500MPa. The springback angle of hot bending part increases by increasing the die radius, by increasing the gap between the punch and the die. Springback is mainly negative caused by/due to different cooling rate and the impact of thermal restoring moments. This provides a basis for the control of the hot stamping process applied in the production of complicated shape parts

    Lung adenocarcinoma with bladder metastasis: A case report and literature review

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    BackgroundLung cancer is the most common cause of cancer-related mortality in the world. Unfortunately, more than 50% of patients have already metastasized at the time of diagnosis, contributing to morbidity and mortality. Common sites of metastasis are adrenal glands, liver, bone, and brain. Bladder metastasis is rare and should prompt a careful differential consideration of primary bladder cancer.Case descriptionHere, we report a 72-year-old female who went to the hospital for “gross hematuria for one day”. Cystoscopy showed space-occupying lesions in the bladder. During the general CT examination, space-occupying lesions in the lower lobe of the lung were found. Peripheral lung cancer with multiple lymph node metastases, pulmonary metastasis, and left pleural effusion were considered. Transurethral cystoscopic resection of the bladder tumor and pleural effusion cell block examination were performed to clarify the diagnosis. Combined with morphological and immunohistochemical results, both pathological results supported a diagnosis of lung adenocarcinoma metastasis, and gene detection was carried out. EGFR, ALK, and ROS-1 were negative. According to the genetic testing results, there was no corresponding targeted drug, so we administered chemotherapy, and one-year survival was achieved, which was better than expected based on other studies.ConclusionThis paper describes a case of lung adenocarcinoma metastatic to the bladder and includes a review of the literature to provide clinicians with diagnostic and treatment experience and help avoid misdiagnosis and mistreatment

    Trends in acupuncture for infertility: a scoping review with bibliometric and visual analysis

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    BackgroundUnexplained recurrent implantation failure and the high cost of assisted reproductive techniques for those experiencing infertility have increasingly resulted in the use of acupuncture. However, the trends and research status of acupuncture on infertility resulting in natural conception have not been systematically summarized. This scoping review and knowledge graph analysis aimed to summarize existing clinical studies on acupuncture for infertility that resulted in natural conception.MethodsSeven databases, namely, PubMed, Embase, the Cochrane Library, CNKI, VIP, Wanfang Data, and SinoMed, were searched up to August 2023 (updated on 1 April). Two authors independently identified related clinical studies and systematic reviews, and extracted data from included studies on acupuncture for infertility; any discrepancies were resolved by discussion or judged by a third author. A meta-analysis was conducted based on randomized controlled trials (RCTs), and data were synthesized using risk ratios with 95% confidence intervals.ResultsOf the 310 articles meeting the inclusion criteria, 274 were primary studies, 7 were systematic reviews, and 29 were case reports. Reported adverse events included mild ovarian irritation and early signs of miscarriage. Out of the 274 primary studies, there were 40 (14.60%) cases of male infertility and 234 (85.40%) cases of female infertility. Current research highlights on acupuncture for infertility focused on female infertility caused by polycystic ovary syndrome, ovulation disorder, and luteinized unruptured follicle syndrome (LUFS), while acupuncture for male infertility was a hotspot in the early research stage. The meta-analysis also suggested that acupuncture was more effective than human chorionic gonadotropin (HCG) [RR = 1.89, 95% CI (1.47, 2.42), 11 RCTs, 662 participants]. Acupuncture combined with HCG was comparable to HCG [RR = 2.33, 95% CI (1.53, 3.55), four RCTs, 259 participants]. Compared with no treatment, acupuncture resulted in a higher pregnancy rate [RR = 22.12, 95% CI (1.39, 353.09), one RCT, 47 participants]. There was no statistical difference between acupuncture combined with HCG plus letrozole and HCG plus letrozole [RR = 1.56, 95% CI (0.84, 2.89), one RCT, 84 participants].ConclusionCurrent research highlights on acupuncture for infertility resulting in natural conception focused on female infertility caused by polycystic ovary syndrome, ovulation disorder, and LUFS, while studies on male infertility and female infertility caused by blockage in the fallopian tube, thin endometrium, and other factors were insufficient. Well-designed confirmatory clinical studies are still needed as the research hypotheses of most studies were unclear

    Single cell atlas for 11 non-model mammals, reptiles and birds.

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    The availability of viral entry factors is a prerequisite for the cross-species transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Large-scale single-cell screening of animal cells could reveal the expression patterns of viral entry genes in different hosts. However, such exploration for SARS-CoV-2 remains limited. Here, we perform single-nucleus RNA sequencing for 11 non-model species, including pets (cat, dog, hamster, and lizard), livestock (goat and rabbit), poultry (duck and pigeon), and wildlife (pangolin, tiger, and deer), and investigated the co-expression of ACE2 and TMPRSS2. Furthermore, cross-species analysis of the lung cell atlas of the studied mammals, reptiles, and birds reveals core developmental programs, critical connectomes, and conserved regulatory circuits among these evolutionarily distant species. Overall, our work provides a compendium of gene expression profiles for non-model animals, which could be employed to identify potential SARS-CoV-2 target cells and putative zoonotic reservoirs
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