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1.
Sensors (Basel) ; 23(13)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37448061

RESUMEN

An improved Dijkstra algorithm based on adaptive resolution grid (ARG) is proposed to assist manual transmission line planning, shorten the construction period and achieve lower cost and higher efficiency of line selection. Firstly, the semantic segmentation network is used to change the remote sensing image into a ground object-identification image and the grayscale image of the ground object-identification image is rasterized. The ARG map model is introduced to greatly reduce the number of redundant grids, which can effectively reduce the time required to traverse the grids. Then, the Dijkstra algorithm is combined with the ARG and the neighborhood structure of the grid is a multi-center neighborhood. An improved method of bidirectional search mechanism based on ARG and inflection point-correction is adopted to greatly increase the running speed. The inflection point-correction reduces the number of inflection points and reduces the cost. Finally, according to the results of the search, the lowest-cost transmission line is determined. The experimental results show that this method aids manual planning by providing a route for reference, improving planning efficiency while shortening the duration, and reducing the time spent on algorithm debugging. Compared with the comparison algorithm, this method is faster in running speed and better in cost saving and has a broader application prospect.


Asunto(s)
Algoritmos , Dispersión de Radiación
2.
Zhongguo Yi Liao Qi Xie Za Zhi ; 46(2): 156-159, 2022 Mar 30.
Artículo en Zh | MEDLINE | ID: mdl-35411741

RESUMEN

Intelligent and precision medical treatment is the future development trend of surgical operations. We proposed a core architecture of orthopedic robots with human-like thinking based on the growing demand for orthopedic robots and disadvantages of current robots, it consists of brain, eyes and hands three modules according to functions. The architecture design is extremely in line with the doctor's logic so that the work process of the orthopedic robot is similar to the process of traditional surgery which is mainly done by the doctor's brain-eye-hand coordination. It realizes the digitization of the doctor's thinking, the immediacy and visualization of surgical information and the accuracy of surgical operation process. The clinical application proved that the orthopedic robot has the advantages of higher accuracy, less radiation and shorter operation time, which can be further promoted clinically.


Asunto(s)
Robótica , Mano , Humanos
3.
Zhongguo Yi Liao Qi Xie Za Zhi ; 46(3): 318-322, 2022 May 30.
Artículo en Zh | MEDLINE | ID: mdl-35678444

RESUMEN

In the perspective of technical evaluation, the pre-marketing regulatory requirements of allergen detection reagents in China, America, European Union were compared, and the regulatory risks and performance requirements of this product were analyzed based on the monitoring of post-marketing adverse events, reference standards and domestic and foreign regulatory documents. In view of the "neck-stuck" problems such as the difficulty of clinical trials, the difficulty of finding comparable contrast reagents and the lack of clinical diagnostic gold standards, this paper discusses and gives regulatory suggestions, with a view to providing technical reference for product R&D, production, evaluation, approval and supervision in this field.


Asunto(s)
Alérgenos , Mercadotecnía , Unión Europea , Indicadores y Reactivos , Estándares de Referencia
4.
J Nanobiotechnology ; 19(1): 61, 2021 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-33639970

RESUMEN

BACKGROUND: Exosome transplantation is a promising cell-free therapeutic approach for the treatment of ischemic heart disease. The purpose of this study was to explore whether exosomes derived from Macrophage migration inhibitory factor (MIF) engineered umbilical cord MSCs (ucMSCs) exhibit superior cardioprotective effects in a rat model of AMI and reveal the mechanisms underlying it. RESULTS: Exosomes isolated from ucMSCs (MSC-Exo), MIF engineered ucMSCs (MIF-Exo) and MIF downregulated ucMSCs (siMIF-Exo) were used to investigate cellular protective function in human umbilical vein endothelial cells (HUVECs) and H9C2 cardiomyocytes under hypoxia and serum deprivation (H/SD) and infarcted hearts in rats. Compared with MSC-Exo and siMIF-Exo, MIF-Exo significantly enhanced proliferation, migration, and angiogenesis of HUVECs and inhibited H9C2 cardiomyocyte apoptosis under H/SD in vitro. MIF-Exo also significantly inhibited cardiomyocyte apoptosis, reduced fibrotic area, and improved cardiac function as measured by echocardiography in infarcted rats in vivo. Exosomal miRNAs sequencing and qRT-PCR confirmed miRNA-133a-3p significantly increased in MIF-Exo. The biological effects of HUVECs and H9C2 cardiomyocytes were attenuated with incubation of MIF-Exo and miR-133a-3p inhibitors. These effects were accentuated with incubation of siMIF-Exo and miR-133a-3p mimics that increased the phosphorylation of AKT protein in these cells. CONCLUSION: MIF-Exo can provide cardioprotective effects by promoting angiogenesis, inhibiting apoptosis, reducing fibrosis, and preserving heart function in vitro and in vivo. The mechanism in the biological activities of MIF-Exo involves miR-133a-3p and the downstream AKT signaling pathway.


Asunto(s)
Exosomas/metabolismo , Factores Inhibidores de la Migración de Macrófagos/farmacología , Células Madre Mesenquimatosas/efectos de los fármacos , MicroARNs/metabolismo , Infarto del Miocardio/tratamiento farmacológico , Animales , Apoptosis , Línea Celular , Proliferación Celular , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Oxidorreductasas Intramoleculares , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Masculino , Células Madre Mesenquimatosas/metabolismo , Infarto del Miocardio/metabolismo , Miocardio , Miocitos Cardíacos/metabolismo , Ratas , Transducción de Señal , Regulación hacia Arriba
5.
J Cell Physiol ; 235(11): 8010-8022, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-31960418

RESUMEN

Accumulating evidence has shown that mesenchymal stem cell (MSC)-derived exosomes (exo) mediate cardiac repair following myocardial infarction (MI). Macrophage migration inhibitory factor (MIF), a proinflammatory cytokine, plays a critical role in regulating cell homeostasis. This study aimed to investigate the cardioprotective effects of exo secreted from bone marrow-MSCs (BM-MSCs) overexpressing MIF in a rat model of MI. MIF plasmid was transducted in BM-MSCs. Exo were isolated from the supernatants of BM-MSCs and MIF-BM-MSCs, respectively. The morphology of mitochondria in neonatal mice cardiomyocytes (NRCMs) was determined by MitoTracker staining. The apoptosis of NRCMs was examined by deoxynucleotidyl transferase-mediated dUTP nick end-labeling. BM-MSC-exo and MIF-BM-MSC-exo were intramuscularly injected into the peri-infarct region in a rat model of MI. The heart function of rats was assessed by echocardiography. The expression of MIF was greatly enhanced in MIF-BM-MSCs compared with BM-MSCs. Both BM-MSC-exo and MIF-BM-MSC-exo expressed CD63 and CD81. NRCMs treated with MIF-BM-MSC-exo exhibited less mitochondrial fragmentation and cell apoptosis under hypoxia/serum deprivation (H/SD) challenge than those treated with BM-MSC-exo via activating adenosine 5'-monophosphate-activated protein kinase signaling. Moreover, these effects were partially abrogated by Compound C. Injection of BM-MSC-exo or MIF-BM-MSC-exo greatly restored heart function in a rat model of MI. Compared with BM-MSC-exo, injection of MIF-BM-MSC-exo was associated with enhanced heart function, reduced heart remodeling, less cardiomyocyte mitochondrial fragmentation, reactive oxygen species generation, and apoptosis. Our study reveals a new mechanism of MIF-BM-MSC-exo-based therapy for MI and provides a novel strategy for cardiovascular disease treatment.


Asunto(s)
Exosomas/genética , Oxidorreductasas Intramoleculares/genética , Factores Inhibidores de la Migración de Macrófagos/genética , Infarto del Miocardio/genética , Animales , Apoptosis/genética , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Modelos Animales de Enfermedad , Humanos , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , Infarto del Miocardio/patología , Infarto del Miocardio/rehabilitación , Miocardio/metabolismo , Miocardio/patología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Ratas , Transducción de Señal
6.
Cardiology ; 145(3): 130-135, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32015236

RESUMEN

INTRODUCTION: Changes in electrocardiogram (ECG) parameters and the incidence of arrhythmic events in patients with fever-induced Brugada syndrome (BrS) remain unknown. OBJECTIVE: We aimed to investigate the effect of hyperthermia on the ECG pattern and the occurrence of fever-triggered arrhythmic events (FTAEs) in patients with fever-induced BrS. METHODS: We retrospectively analyzed a series of fever-induced BrS cases from January 1966 to November 2018. Clinical characteristics and ECG parameters were evaluated in the presence or absence of fever. RESULTS: Syncope and implantable cardioverter defibrillator implantation occurred more frequently in BrS patients with FTAEs than in patients without FTAEs. In BrS patients <16 years old, more arrhythmia events occurred in patients with FTAEs than in patients without FTAEs (p = 0.04). During follow-up, 2 patients in the FTAEs group suffered new malignant arrhythmic events. Compared to the afebrile state, the J point increased significantly in precordial leads V1, V2, and V3 during the febrile state (all p < 0.01). The corrected QTpeak intervals in V1 and V2 were significantly longer in the FTAEs group than in the non-FTAEs group (354.5 ± 37.0 vs. 334.3 ± 45.5 ms, p < 0.01 and 368.0 ± 43.4 vs. 330.9 ± 41.5 ms, p < 0.01, respectively). An increased corrected QT dispersion and a lengthened corrected Tpeak-Tend dispersion were also observed during fever. CONCLUSIONS: Fever may not only reveal BrS but also induce life-threatening arrhythmic events, especially in children and adolescents.


Asunto(s)
Síndrome de Brugada/complicaciones , Electrocardiografía , Fibrilación Ventricular/etiología , Adulto , Síndrome de Brugada/fisiopatología , Desfibriladores Implantables , Femenino , Fiebre/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Síncope/etiología , Fibrilación Ventricular/fisiopatología
7.
Pacing Clin Electrophysiol ; 43(1): 54-61, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31721241

RESUMEN

BACKGROUND: Recurrence rates after catheter radiofrequency ablation (RFA) for arrhythmias arising from deep myocardial substrates can exceed 40%. Failure of RFA is in part due to the inability of widely used unipolar ablation (UA) to create transmural lesions capable of disrupting the critical components of the arrhythmia circuit. A radiofrequency generator was custom-made to deliver bipolar ablation (BA) to test the hypothesis that BA is more effective compared to UA in achieving transmurality and to determine the optimal configuration for ventricular BA. METHODS: Sequential UA and BA were created in porcine ventricular septal and free wall preparations using irrigated, contact-force sensing ablation catheters, orientated perpendicularly to the myocardium. Return catheters, durations of ablation, irrigating fluids, and power settings were varied to determine the optimal configuration for BA. Lesion characteristics, transmurality, and occurrence of steam pops were analyzed. RESULTS: In both ventricular septal and free wall models, BA resulted in significantly more transmural lesions while causing less steam pops (P < .01). BA lesions were deeper, narrower but larger in volume. Use of 8 mm ground catheters in the epicardium resulted in overheating during BA with temperatures exceeding 95°C, limiting power delivery. Increasing duration and powers of BA resulted in progressively larger lesions and increased transmurality (all P < .01), and 0.45% saline as the irrigation did not enhance BA. CONCLUSION: BA created larger lesions with increased chances of transmurality but at lower risks of steam pops. Use of an irrigated catheter as the return electrode and 30 W of BA delivered over 120 seconds provides the optimal balance between creating deep, transmural lesions and avoiding steam pops.


Asunto(s)
Ablación por Catéter/instrumentación , Ventrículos Cardíacos/cirugía , Animales , Catéteres Cardíacos , Electrodos , Diseño de Equipo , Técnicas In Vitro , Modelos Animales , Porcinos , Irrigación Terapéutica
8.
Pacing Clin Electrophysiol ; 43(8): 822-827, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32363589

RESUMEN

BACKGROUND: There are unique advantages and disadvantages in the choice of contact mapping (CM) versus noncontact mapping (NCM) systems during ablation of right ventricular outflow tract (RVOT) arrhythmias. This study compared acute procedural success and clinical outcomes in matched patients undergoing CM- versus NCM-guided RVOT ablation. METHODS: A total of 167 consecutive patients with idiopathic RVOT ventricular arrhythmias underwent NCM- or CM-guided ablation. Propensity scoring was used to match each patient undergoing NCM-guided ablation to one control patient undergoing CM-guided ablation. RESULTS: A total of 120 patients were included in this final analysis. If initial ablation was acutely unsuccessful in either group, patients crossed over to the other group. Ablation was acutely successful in 47 of 60 (78.3 %) patients in the NCM group and 55 of 60 (91.7%) in the CM group (P = .002). Thirteen NCM patients required CM and two CM patients crossed over to utilize NCM (P = .002). Procedural duration, fluoroscopy time, and dose in NCM were greater than that in CM (P < .05, respectively). However, procedural complications were not different between two groups. During a mean follow-up of 51 ± 20.6 months, 51 of the 60 NCM patients remained free of arrhythmia, while 48 of the 60 CM patients had no recurrent arrhythmias (P = .47). CONCLUSION: Contact mapping, compared to NCM, is the superior initial technique to guide RVOT arrhythmia ablation due to a higher procedural success without the need to switch to alternative mapping techniques and shorter procedural and fluoroscopic times.


Asunto(s)
Ablación por Catéter/métodos , Taquicardia Ventricular/cirugía , Complejos Prematuros Ventriculares/cirugía , Electrocardiografía , Mapeo Epicárdico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Puntaje de Propensión , Estudios Retrospectivos , Taquicardia Ventricular/fisiopatología , Complejos Prematuros Ventriculares/fisiopatología
9.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(3): 249-252, 2020 Mar 08.
Artículo en Zh | MEDLINE | ID: mdl-32621435

RESUMEN

At present, there is a growing call for overseas registration applicants to transfer the products that have been approved for import registration to China's domestic production. It deserves our regulatory authorities to study how to face and properly deal with this issue. First of all, this paper systematically combs the regulatory requirements of FDA, EU and Japan on the change of manufacturing site address. Secondly, the paper briefly analyzes the current regulatory differences between domestic and imported devices. Finally, according to the experience and practice of foreign countries, combined with the actual situation of our country, this paper puts forward suggestions on how to meet the needs of overseas registrants to transfer products to domestic production.


Asunto(s)
Mercadotecnía , Equipos y Suministros
10.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(6): 537-540, 2020 Dec 08.
Artículo en Zh | MEDLINE | ID: mdl-33314864

RESUMEN

From the perspective of technical review, this paper made statistics on the supplement contents of in vitro diagnostic reagent (kit) for clinical chemistry registered in Zhejiang province in the past five years, summarized and analyzed the common problems, and put forward corresponding suggestions based on the common problems encountered in the public welfare training of registered specialists in Zhejiang province. The aim is to provide technical reference for registrars to prepare registration documents reasonably and efficiently and for review staffs to strengthen their points of focus.


Asunto(s)
Química Clínica/normas , Juego de Reactivos para Diagnóstico/normas , China , Indicadores y Reactivos
11.
Zhongguo Yi Liao Qi Xie Za Zhi ; 43(1): 48-50, 2019 Jan 30.
Artículo en Zh | MEDLINE | ID: mdl-30770691

RESUMEN

In October 2017, the General Office of the CPC Central Committee and the General Office of the State Council issued "The opinion on deepening the reform of the review and approval system and encouraging the innovation in pharmaceutical and medical devices" which clearly requires the unification of the evaluation stand for the second class medical device and realizes national review gradually. According to this requirement, this paper firstly reviews situation of foreign medical device evaluation system, and then introduces general situation of medical device review in our country, including the establishment of institutions and existed problem of medical device registrations, and corresponding reasons are also be analyzed. Finally we focus on giving proposal on how to realize the unification of class Ⅱ medical device technology review in China combined with real situation based on referring foreign experience.


Asunto(s)
Aprobación de Recursos , Tecnología , China
12.
Zhongguo Yi Liao Qi Xie Za Zhi ; 42(2): 95-98, 2018 Feb 08.
Artículo en Zh | MEDLINE | ID: mdl-29845807

RESUMEN

The combination of mobile medical technology and the grading diagnosis and treatment system (GDTS) can stimulate the allocation of medical resources, reduce medical cost and improve public health significantly. Firstly we summarize development features of mobile medical technology in foreign and domestic market, then we study the application model of mobile medical application in GDTS with field research data and analyzes its advantage and shortage. Finally, we propose four measures for further developing mobile medical application in the GDTS:the government departments should formulate policies and industry standards of products as soon as possible to meet requirement of market; service providers should take the hospitals as core role to achieve mutual benefit and win-win situation; take the daily monitoring of chronic diseases as an entry point to build profitable business model; enhance publicity to promote public health awareness.


Asunto(s)
Diagnóstico , Aplicaciones Móviles , Tecnología/tendencias , Salud Pública
13.
IEEE Trans Image Process ; 33: 4145-4158, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38954578

RESUMEN

Video question answering (VideoQA) requires the ability of comprehensively understanding visual contents in videos. Existing VideoQA models mainly focus on scenarios involving a single event with simple object interactions and leave event-centric scenarios involving multiple events with dynamically complex object interactions largely unexplored. These conventional VideoQA models are usually based on features extracted from the global visual signals, making it difficult to capture the object-level and event-level semantics. Although there exists a recent work utilizing a static spatio-temporal graph to explicitly model object interactions in videos, it ignores the dynamic impact of questions for graph construction and fails to exploit the implicit event-level semantic clues in questions. To overcome these limitations, we propose a Self-supervised Dynamic Graph Reasoning (SDGraphR) model for video question answering (VideoQA). Our SDGraphR model learns a question-guided spatio-temporal graph that dynamically encodes intra-frame spatial correlations and inter-frame correspondences between objects in the videos. Furthermore, the proposed SDGraphR model discovers event-level cues from questions to conduct self-supervised learning with an auxiliary event recognition task, which in turn helps to improve its VideoQA performances without using any extra annotations. We carry out extensive experiments to validate the substantial improvements of our proposed SDGraphR model over existing baselines.

14.
Artículo en Inglés | MEDLINE | ID: mdl-38949944

RESUMEN

Disentangled Representation Learning (DRL) aims to learn a model capable of identifying and disentangling the underlying factors hidden in the observable data in representation form. The process of separating underlying factors of variation into variables with semantic meaning benefits in learning explainable representations of data, which imitates the meaningful understanding process of humans when observing an object or relation. As a general learning strategy, DRL has demonstrated its power in improving the model explainability, controlability, robustness, as well as generalization capacity in a wide range of scenarios such as computer vision, natural language processing, and data mining. In this article, we comprehensively investigate DRL from various aspects including motivations, definitions, methodologies, evaluations, applications, and model designs. We first present two well-recognized definitions, i.e., Intuitive Definition and Group Theory Definition for disentangled representation learning. We further categorize the methodologies for DRL into four groups from the following perspectives, the model type, representation structure, supervision signal, and independence assumption. We also analyze principles to design different DRL models that may benefit different tasks in practical applications. Finally, we point out challenges in DRL as well as potential research directions deserving future investigations. We believe this work may provide insights for promoting the DRL research in the community.

15.
Nanoscale ; 16(29): 13979-13987, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38984609

RESUMEN

The vertical motion configuration is a common design in triboelectric nanogenerators (TENGs) for energy harvesting; however, the performance optimization and comparison are still vague between various vertical motion-based structures. In this paper, time-averaged power density is defined as a metric to compare the power output performances of vertically structured TENGs, including contact mode and freestanding mode. To ensure comparisons under the same circumstances, a novel sandwich-structured dielectric layer was designed to maintain a stable and consistent surface charge density, with an extra rotating triboelectric nanogenerator working as a charge pump. We also investigated the impact of parasitic capacitance, which is a primary source of error in theoretical optimization. The freestanding TENG (FTENG) with a single dielectric layer demonstrates superior power performance, even when accounting for the influence of parasitic capacitance. This work provides valuable insights and guidelines for the design of high-performance mechanical energy harvesting devices.

16.
ACS Pharmacol Transl Sci ; 7(3): 743-756, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38481697

RESUMEN

Aging poses obstacles to the functionality of human mesenchymal stem cells (MSCs), resulting in a notable decline in their valuable contribution to myocardial infarction (MI). MicroRNAs (miRNAs) play a pivotal role in governing MSC aging; nonetheless, the specific mechanisms remain puzzling. This research delved into the value of miR-873-5p in the management of MSC aging and investigated whether the restraint of miR-873-5p could regenerate aged MSCs (AMSCs), thereby enhancing their healing success for MI. In this study, MSCs were isolated from both young donors (referred to as YMSCs) and aged donors (referred to as AMSCs). The senescence status of these MSCs was evaluated through the application of age-related ß-galactosidase (SA-ß-gal) staining. Following this assessment, the MSCs, including those treated with anti-miR-873-5p-AMSCs, were then transplanted into the hearts of Sprague-Dawley rats experiencing acute myocardial infarction. Increasing miR-873-5p levels in YMSCs resulted in elevated cellular aging, whereas reducing miR-873-5p expression decreased aging in AMSCs. Mechanistically, miR-873-5p inhibited autophagy in MSCs through the AMPK signaling pathway, leading to cellular aging by suppressing the Cab39 expression. Partial alleviation of these effects was achieved by the administration of the autophagy inhibitor 3-methyladenine. Grafting of anti-miR-873-5p-AMSCs, by enhancing angiogenesis and bolstering cell survival, led to an improvement in cardiac function in the rat model, unlike the transplantation of AMSCs. miR-873-5p which serves as a pivotal element in mediating MSC aging through its regulation of the Cab39/AMPK signaling pathway. It represents an innovative target for revitalizing AMSCs and enhancing their heart-protective abilities.

17.
Imeta ; 3(1): e162, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38868512

RESUMEN

Regulation on denitrifying microbiomes is crucial for sustainable industrial biotechnology and ecological nitrogen cycling. The holistic genetic profiles of microbiomes can be provided by meta-omics. However, precise decryption and further applications of highly complex microbiomes and corresponding meta-omics data sets remain great challenges. Here, we combined optogenetics and geometric deep learning to form a discover-model-learn-advance (DMLA) cycle for denitrification microbiome encryption and regulation. Graph neural networks (GNNs) exhibited superior performance in integrating biological knowledge and identifying coexpression gene panels, which could be utilized to predict unknown phenotypes, elucidate molecular biology mechanisms, and advance biotechnologies. Through the DMLA cycle, we discovered the wavelength-divergent secretion system and nitrate-superoxide coregulation, realizing increasing extracellular protein production by 83.8% and facilitating nitrate removal with 99.9% enhancement. Our study showcased the potential of GNNs-empowered optogenetic approaches for regulating denitrification and accelerating the mechanistic discovery of microbiomes for in-depth research and versatile applications.

18.
IEEE Trans Pattern Anal Mach Intell ; 45(4): 4321-4334, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35839195

RESUMEN

Neural-symbolic learning, aiming to combine the perceiving power of neural perception and the reasoning power of symbolic logic together, has drawn increasing research attention. However, existing works simply cascade the two components together and optimize them isolatedly, failing to utilize the mutual enhancing information between them. To address this problem, we propose DeepLogic, a framework with joint learning of neural perception and logical reasoning, such that these two components are jointly optimized through mutual supervision signals. In particular, the proposed DeepLogic framework contains a deep-logic module that is capable of representing complex first-order-logic formulas in a tree structure with basic logic operators. We then theoretically quantify the mutual supervision signals and propose the deep&logic optimization algorithm for joint optimization. We further prove the convergence of DeepLogic and conduct extensive experiments on model performance, convergence, and generalization, as well as its extension to the continuous domain. The experimental results show that through jointly learning both perceptual ability and logic formulas in a weakly supervised manner, our proposed DeepLogic framework can significantly outperform DNN-based baselines by a great margin and beat other strong baselines without out-of-box tools.

19.
IEEE Trans Pattern Anal Mach Intell ; 45(1): 408-424, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35196226

RESUMEN

There exist complex interactions among a large number of latent factors behind the decision making processes of different individuals, which drive the various user behavior patterns in recommender systems. These factors hidden in those diverse behaviors demonstrate highly entangled patterns, covering from high-level user intentions to low-level individual preferences. Uncovering the disentanglement of these latent factors can benefit in enhanced robustness, interpretability, and controllability during representation learning for recommendation. However, the large degree of entanglement within latent factors poses great challenges for learning representations that disentangle them, and remains largely unexplored in literature. In this paper, we present the SEMantic MACRo-mIcro Disentangled Variational Auto-Encoder (SEM-MacridVAE) model for learning disentangled representations from user behaviors, taking item semantic information into account. Our SEM-MacridVAE model achieves macro disentanglement by inferring the high-level concepts associated with user intentions (e.g., to buy a pair of shoes or a laptop) through a prototype routing mechanism, as well as capturing the individual preferences with respect to different concepts separately. The micro disentanglement is guaranteed through a micro-disentanglement regularizer stemming from an information-theoretic interpretation of VAEs, which forces each dimension of the representations to independently reflect an isolated low-level factor (e.g., the size or the color of a shirt). The semantic information including visual and categorical signals extracted from candidate items is utilized to further boost the recommendation performance of the proposed SEM-MacridVAE model. Empirical experiments demonstrate that our proposed approach is able to achieve significant improvement over the state-of-the-art baselines. We also show that the learned representations are interpretable and controllable, capable of potentially leading to a new paradigm for recommendation where users have fine-grained control over some target aspects of the recommendation candidates.

20.
Clin Interv Aging ; 18: 283-292, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36851975

RESUMEN

Objective: In this study, a risk score for ventricular arrhythmias (VA) were evaluated for predicting the risk of ventricular arrhythmia (VA) of acute myocardial infarction (AMI) patients. Methods: Patients with AMI were divided into two sets according to whether VA occurred during hospitalization. Another cohort was enrolled for external validation. The area under the curve (AUC) of receiver operating characteristic (ROC) was calculated to evaluate the accuracy of the model. Results: A total of 1493 eligible patients with AMI were enrolled as the training set, of whom 70 (4.7%) developed VA during hospitalization. In-hospital mortality was significantly higher in the VA set than in the non-VA set (31.4% vs 2.7%, P=0.001). The independent predictors of VA in patients with AMI including Killip grade ≥3, STEMI patients, LVEF <50%, frequent premature ventricular beats, serum potassium <3.5 mmol/L, type 2 diabetes, and creatinine level. The AUC of the model for predicting VT/VF in the training set was 0.815 (95% CI: 0.763-0.866). A total of 1149 cases were enrolled from Xuzhou Center Hospital as the external validation set. The AUC of the model in the external validation set for predicting VT/VF was 0.755 (95% CI: 0.687-0.823). Calibration curves indicated a good consistency between the predicted and the observed probabilities of VA in both sets. Conclusion: We have established a clinical prediction risk score for predicting the occurrence of VA in AMI patients. The prediction score is easy to use, performs well and can be used to guide clinical practice.


Asunto(s)
Diabetes Mellitus Tipo 2 , Infarto del Miocardio , Infarto del Miocardio con Elevación del ST , Humanos , Arritmias Cardíacas/diagnóstico , Infarto del Miocardio/complicaciones , Infarto del Miocardio con Elevación del ST/complicaciones , Área Bajo la Curva
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