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1.
Radiol Clin North Am ; 61(1): 141-150, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36336387

RESUMO

Peripheral vascular injuries are a rare finding in the setting of trauma but an important source of morbidity and mortality when present. Fast and accurate diagnosis followed by rapid repair of vascular injuries are important for achieving the best clinical outcomes. The advancements in computer tomography (CT) and decades of experience in vascular imaging have allowed radiologists to become important contributors for the diagnosis and characterization of peripheral vascular injury. We review the epidemiology of peripheral vascular injuries, indications for imaging, ways to optimize CT technique, imaging findings, and common challenges for accurate diagnosis of such injuries.


Assuntos
Lesões do Sistema Vascular , Humanos , Lesões do Sistema Vascular/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Tomografia Computadorizada por Raios X/métodos , Angiografia/métodos , Computadores
2.
Mol Phylogenet Evol ; 178: 107636, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36208695

RESUMO

Phylogenetic trees are essential tools in evolutionary biology that present information on evolutionary events among organisms and molecules. From a dataset of n sequences, a phylogenetic tree of (2n-5)!! possible topologies exists, and determining the optimum topology using brute force is infeasible. Recently, a recursive graph cut on a graph-represented-similarity matrix has proven accurate in reconstructing a phylogenetic tree containing distantly related sequences. However, identifying the optimum graph cut is challenging, and approximate solutions are currently utilized. Here, a phylogenetic tree was reconstructed with an improved graph cut using a quantum-inspired computer, the Fujitsu Digital Annealer (DA), and the algorithm was named the "Normalized-Minimum cut by Digital Annealer (NMcutDA) method". First, a criterion for the graph cut, the normalized cut value, was compared with existing clustering methods. Based on the cut, we verified that the simulated phylogenetic tree could be reconstructed with the highest accuracy when sequences were diverged. Moreover, for some actual data from the structure-based protein classification database, only NMcutDA could cluster sequences into correct superfamilies. Conclusively, NMcutDA reconstructed better phylogenetic trees than those using other methods by optimizing the graph cut. We anticipate that when the diversity of sequences is sufficiently high, NMcutDA can be utilized with high efficiency.


Assuntos
Algoritmos , Computadores , Filogenia , Análise por Conglomerados , Bases de Dados de Proteínas
3.
Sci Total Environ ; 856(Pt 1): 159096, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36181826

RESUMO

Antibiotic resistance genes (ARGs) have been regarded as emerging pollutants due to their potential risk of resistance. Horizontal gene transfer (HGT) is the main pathway for ARGs to lead to environmental threats. Therefore, the inhabitation of ARGs' HGT can effectively inhibit ARGs' potential drug resistance risk within a single strain. In this paper, the characteristics of ARGs' HGT in paddy and dryland soils were identified and regulated by a combination of ARGs' HGT feature identification, transfer mechanism analysis and transfer process regulation. The homology modeling algorithm was used to simulate the construction of the Tn5 plasmid transposase of Escherichia coli (E. coli) for identifying ARGs' HGT characteristics. The GCG (212.617 Å) was thus determined as the target codon. Through integrated computer-based methods, results showed that the most important environmental disturbance factors for the HGT of ARGs in the paddy and dryland soils were rough farmyard manure/sewage irrigation and mining pollution, respectively. Under the disturbance of key environmental factors, the inhibitory effect of HGT of ARGs in paddy and dryland soil was reduced by 35.01 % and 34.74 %, respectively. Results demonstrated that the proposed theoretical mechanism and control strategies could effectively inhibit the HGT of E. coli ARGs in the soil environment.


Assuntos
Transferência Genética Horizontal , Solo , Antibacterianos/farmacologia , Escherichia coli/genética , Genes Bacterianos , Resistência Microbiana a Medicamentos/genética , Computadores
5.
Methods Mol Biol ; 2552: 409-433, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36346606

RESUMO

In the computational design of antibodies, the interaction analysis between target antigen and antibody is an essential process to obtain feedback for validation and optimization of the design. Kinetic and thermodynamic parameters as well as binding affinity (KD) allow for a more detailed evaluation and understanding of the molecular recognition. In this chapter, we summarize the conventional experimental methods which can calculate KD value (ELISA, FP), analyze a binding activity to actual cells (FCM), and evaluate the kinetic and thermodynamic parameters (ITC, SPR, BLI), including high-throughput analysis and a recently developed experimental technique.


Assuntos
Anticorpos , Antígenos , Ensaio de Imunoadsorção Enzimática , Cinética , Computadores
6.
Appl Ergon ; 106: 103896, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36156386

RESUMO

Worker guidance systems provide product-specific and digital assembly information and can make an important contribution to increasing productivity and quality and relieving employees, especially in flexible variant assembly. However, a critical factor here is the successful design of the systems. While much of the research focuses on aspects of the hardware, this article is dedicated to the question of how the configuration of the level of information, i.e. the amount and depth of information in worker guidance systems, is affected. For this purpose, two studies, a laboratory study at the Technical University of Darmstadt (N = 53) and a field study at a company (N = 30), were conducted and two variants of the information level of a worker guidance system were compared. The study results show that assembly quality in particular is significantly influenced by the level of information; to the advantage of detailed information. No significant differences were found for production times. For the subjective evaluation of the system as well as for the objective and subjectively perceived strain, it can be stated that the high level of information also performs better. The results thus help to design worker guidance systems more precisely so that they fulfill the information needs of the employees as well as possible.


Assuntos
Computadores , Eficiência , Humanos
7.
J. Health Biol. Sci. (Online) ; 10(1): 1-5, 01/jan./2022. ilus
Artigo em Inglês | LILACS | ID: biblio-1370898

RESUMO

Introduction: The use of computers, tablets, and cell phones with the Internet by people with quadriplegia from spinal cord injuries is much lower when compared to the general population. The quality of life of these people can be substantially improved through access to these technologies, which would allow a quadriplegic to take advantage of the rapid evolution of information and communication. Many of these individuals have the function of preserved neck and mouth muscles, and it is possible to manipulate intraoral devices as an adaptation tool. Case Report: We report an intraoral device installation in a patient with quadriplegia, a victim of a firearm accident, who had a great desire to reuse the tablet for internet access. A device made of acrylic resin, similar to a myorelaxant plate, was designed to allow the use of a computer that was comfortable and at the same time, the patient could talk and not harm the dental structures. The person responsible agreed to participate in the research and signed the consent form. In addition, the work was submitted to an ethics committee. Considerations: The ideal intra-oral device for patient rehabilitation should be inexpensive, easy to adapt and promote muscle relaxation besides allowing the patient to expand their abilities and digitally increase their autonomy for society.


Introdução: O uso de computadores, tablets e celulares com internet por pessoas com tetraplegia por lesão medular é muito menor quando comparado à população geral. A qualidade de vida dessas pessoas pode ser, substancialmente, melhorada por meio do acesso a essas tecnologias, o que permitiria aos tetraplégicos aproveitar a rápida evolução da informação e da comunicação. Muitos desses indivíduos têm a função de músculos cervicais e bucais preservados, sendo possível a manipulação de dispositivos intraorais como ferramenta de adaptação. Relato de Caso: Relatamos a instalação de um dispositivo intraoral em um paciente com tetraplegia, vítima de acidente com arma de fogo, que tinha grande desejo de reutilizar o tablet para acesso à internet. Um dispositivo feito de resina acrílica, semelhante a uma placa miorrelaxante, foi projetado para permitir o uso de um computador que fosse confortável e, ao mesmo tempo, o paciente pudesse falar e não prejudicar as estruturas dentárias. O responsável concordou em participar da pesquisa e assinou o termo de consentimento. Além disso, o trabalho foi submetido a um comitê de ética. Considerações: O dispositivo intraoral ideal para a reabilitação do paciente deve ser barato, de fácil adaptação e promover o relaxamento muscular, além de permitir que o paciente amplie suas habilidades e aumente sua autonomia pessoal, digitalmente para a sociedade.


Assuntos
Inclusão Digital , Inclusão Social , Quadriplegia , Computadores , Pessoas com Deficiência , Comunicação , Adaptação a Desastres , Autonomia Pessoal
8.
Sci Rep ; 12(1): 18815, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335221

RESUMO

One of the most challenging topics in robotics is simultaneous localization and mapping (SLAM) in the indoor environments. Due to the fact that Global Navigation Satellite Systems cannot be successfully used in such environments, different data sources are used for this purpose, among others light detection and ranging (LiDARs ), which have advanced from numerous other technologies. Other embedded sensors can be used along with LiDARs to improve SLAM accuracy, e.g. the ones available in the Inertial Measurement Units and wheel odometry sensors. Evaluation of different SLAM algorithms and possible hardware configurations in real environments is time consuming and expensive. In our study, we evaluate the accuracy of mapping and localization (based on Absolute Trajectory Error and Relative Pose Error). Our use case is a robot used for room decontamination. The results for a small room show that for our robot the best hardware configuration consists of three LiDARs 2D, IMU and wheel odometry sensors. On the other hand, for long hallways, a configuration with one LiDAR 3D sensor and IMU works better and more stable. We also described a general approach together with tools and procedures that can be used to find the best sensor setup in simulation.


Assuntos
Robótica , Ferramenta de Busca , Robótica/métodos , Algoritmos , Simulação por Computador , Computadores
9.
Comput Intell Neurosci ; 2022: 7186687, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36419507

RESUMO

In most developing countries, the contribution of agriculture to gross domestic product is significant. Plant disease is one of the major factors that adversely affect crop yield. Traditional plant disease detection techniques are time-consuming, biased, and ineffective. Potato is among the top consumed plants in the world, in general, and in developing countries, in particular. However, potato is affected by different kinds of diseases which minimize their yield and quantity. The advancement in AI and machine learning has paved the way for new methods of tackling plant disease detection. This study presents a comprehensive systematic literature review on the major diseases that harm potato crops. In this effort, computer vision-based techniques are employed to identify potato diseases, and types of machine learning algorithms used are surveyed. In this review, 39 primary studies that have provided useful information about the research questions are chosen. Accordingly, the most common potato diseases are found to be late blight, early blight, and bacterial wilt. Furthermore, the review discovered that deep learning algorithms were more frequently used to detect crop diseases than classical machine learning algorithms. Finally, the review categorized the state-of-the-art algorithms and identifies open research problems in the area.


Assuntos
Solanum tuberosum , Doenças das Plantas , Plantas , Algoritmos , Computadores
10.
PLoS One ; 17(11): e0277940, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36413552

RESUMO

Numerical solution of partial differential equations on parallel computers using domain decomposition usually requires synchronization and communication among the processors. These operations often have a significant overhead in terms of time and energy. In this paper, we propose communication-efficient parallel algorithms for solving partial differential equations that alleviate this overhead. First, we describe an asynchronous algorithm that removes the requirement of synchronization and checks for termination in a distributed fashion while maintaining the provision to restart iterations if necessary. Then, we build on the asynchronous algorithm to propose an event-triggered communication algorithm that communicates the boundary values to neighboring processors only at certain iterations, thereby reducing the number of messages while maintaining similar accuracy of solution. We demonstrate our algorithms on a successive over-relaxation solver for the pressure Poisson equation arising from variable density incompressible multiphase flows in 3-D and show that our algorithms improve time and energy efficiency.


Assuntos
Algoritmos , Computadores , Comunicação
12.
J Craniofac Surg ; 33(8): 2606-2608, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36409878

RESUMO

BACKGROUND: Isolated depressed zygomatic arch fractures are often treated with closed reduction. Reduction is usually performed through the Gillies approach or Keen approach. comminuted zygomatic arch fractures generally require open reduction and fixation to achieve good results. This article describes how to use a pair of surgical templates to assist in the fixation of comminuted zygomatic arch fractures with absorbable plates. METHODS: A pair of computer-designed surgical templates were applied to restore the main part of zygomatic arch. Placing a surgical template on the medial side of the zygomatic arch can provide a supporting force and improves the stability of the reduced bone fragments. The lateral template of zygomatic arch limits the excessive uplift of bone fragments. RESULTS AND DISCUSSION: The operation was performed according to the predetermined procedure. Postoperative computed tomography showed satisfactory reduction effect. In conclusion, with the aid of surgical templates, the reduction and fixation of comminuted zygomatic arch fractures can be more easily performed using absorbable plates.


Assuntos
Fraturas Cominutivas , Fraturas Cranianas , Fraturas Zigomáticas , Humanos , Fraturas Zigomáticas/diagnóstico por imagem , Fraturas Zigomáticas/cirurgia , Zigoma/diagnóstico por imagem , Zigoma/cirurgia , Fraturas Cominutivas/diagnóstico por imagem , Fraturas Cominutivas/cirurgia , Computadores
13.
Prog Orthod ; 23(1): 39, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36404385

RESUMO

BACKGROUND: With advances in digital technology, new types of lingual fixed retainers are being developed. However, there are few studies that quantitatively evaluate the accuracy and stability of lingual fixed retainers. The aim of this study was to assess the accuracy and stability of two types of computer-aided customized lingual fixed retainers and a conventional lingual fixed retainer. METHODS: A total of 10 maxillary and 10 mandibular duplicated dental models were selected, and then, three types of retainers were fabricated on the canine-to-canine area for each model. To evaluate accuracy, wire clearance at interproximal area (WCI) was measured using superimposition analysis. Initial flatness deformation was also measured for vertical distortion of retainers. Lateral width, anteroposterior length, and flatness deformation were measured at three-time points for stability assessment. Thermocycling was used to induce 6 months of time flow. RESULTS: The custom-bent group showed significantly higher WCI than the custom-cut and manual groups in the maxillary arch (P = 0.002). The custom-cut group showed significantly less flatness deformation, which was followed by the custom-bent and manual groups in both the maxillary and mandibular arch (P < 0.001). There was no significant difference in stability between the three retainer groups during 5100 cycles of thermocycling (corresponding to 6-month period). CONCLUSIONS: Since there was no difference in stability between the three groups, it is recommended to use custom-cut type retainers in light of accuracy. However, accuracy and stability are not the only factors to consider when selecting type of retainers. Because each retainer has advantages and disadvantages, the type of retainers should be decided in consideration of the clinical environment.


Assuntos
Aparelhos Ortodônticos Fixos , Contenções Ortodônticas , Projetos Piloto , Maxila , Computadores
14.
Comput Intell Neurosci ; 2022: 8342638, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36407688

RESUMO

Federated learning (FL), a distributed machine-learning framework, is poised to effectively protect data privacy and security, and it also has been widely applied in variety of fields in recent years. However, the system heterogeneity and statistical heterogeneity of FL pose serious obstacles to the global model's quality. This study investigates server and client resource allocation in the context of FL system resource efficiency and offers the FedAwo optimization algorithm. This approach combines adaptive learning with federated learning, and makes full use of the computing resources of the server to calculate the optimal weight value corresponding to each client. This approach aggregated the global model according to the optimal weight value, which significantly minimizes the detrimental effects of statistical and system heterogeneity. In the process of traditional FL, we found that a large number of client trainings converge earlier than the specified epoch. However, according to the provisions of traditional FL, the client still needs to be trained for the specified epoch, which leads to the meaningless of a large number of calculations in the client. To further lower the training cost, the augmentation FedAwo ∗ algorithm is proposed. The FedAwo ∗ algorithm takes into account the heterogeneity of clients and sets the criteria for local convergence. When the local model of the client reaches the criteria, it will be returned to the server immediately. In this way, the epoch of the client can dynamically be modified adaptively. A large number of experiments based on MNIST and Fashion-MNIST public datasets reveal that the global model converges faster and has higher accuracy in FedAwo and FedAwo ∗ algorithms than FedAvg, FedProx, and FedAdp baseline algorithms.


Assuntos
Algoritmos , Aprendizado de Máquina , Humanos , Computadores
15.
Nat Commun ; 13(1): 7018, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36384960

RESUMO

Neuromorphic machines are intriguing for building energy-efficient intelligent systems, where spiking neurons are pivotal components. Recently, memristive neurons with promising bio-plausibility have been developed, but with limited reliability, bulky capacitors or additional reset circuits. Here, we propose an anti-ferroelectric field-effect transistor neuron based on the inherent polarization and depolarization of Hf0.2Zr0.8O2 anti-ferroelectric film to meet these challenges. The intrinsic accumulated polarization/spontaneous depolarization of Hf0.2Zr0.8O2 films implements the integration/leaky behavior of neurons, avoiding external capacitors and reset circuits. Moreover, the anti-ferroelectric neuron exhibits low energy consumption (37 fJ/spike), high endurance (>1012), high uniformity and high stability. We further construct a two-layer fully ferroelectric spiking neural networks that combines anti-ferroelectric neurons and ferroelectric synapses, achieving 96.8% recognition accuracy on the Modified National Institute of Standards and Technology dataset. This work opens the way to emulate neurons with anti-ferroelectric materials and provides a promising approach to building high-efficient neuromorphic hardware.


Assuntos
Redes Neurais de Computação , Neurônios , Reprodutibilidade dos Testes , Neurônios/fisiologia , Sinapses/fisiologia , Computadores
16.
Nat Commun ; 13(1): 7019, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36384983

RESUMO

Selective attention is an efficient processing strategy to allocate computational resources for pivotal optical information. However, the hardware implementation of selective visual attention in conventional intelligent system is usually bulky and complex along with high computational cost. Here, programmable ferroelectric bionic vision hardware to emulate the selective attention is proposed. The tunneling effect of photogenerated carriers are controlled by dynamic variation of energy barrier, enabling the modulation of memory strength from 9.1% to 47.1% without peripheral storage unit. The molecular polarization of ferroelectric P(VDF-TrFE) layer enables a single device not only multiple nonvolatile states but also the implementation of selective attention. With these ferroelectric devices are arrayed together, UV light information can be selectively recorded and suppressed the with high current decibel level. Furthermore, the device with positive polarization exhibits high wavelength dependence in the image attention processing, and the fabricated ferroelectric sensory network exhibits high accuracy of 95.7% in the pattern classification for multi-wavelength images. This study can enrich the neuromorphic functions of bioinspired sensing devices and pave the way for profound implications of future bioinspired optoelectronics.


Assuntos
Biônica , Visão Ocular , Computadores
18.
Turk J Ophthalmol ; 52(5): 295-301, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36317741

RESUMO

Objectives: The aim of this study was to investigate the prevalence of symptoms of computer vision syndrome (CVS) and identify its associated risk factors among computer-using bank workers in Pakistan. Materials and Methods: This cross-sectional study was conducted on computer-using bank workers. The data collection procedure included a self-administered questionnaire and comprehensive ocular health examination. The prevalence of CVS and its associated risk factors were investigated. The chi-square test was used to study the significance of the association of CVS with potential risk factors. Results: Of 127 participants, 95 (74.8%) were men. Most of the participants (n=53; 41.7%) were in the 30-40 years age group. A total of 101 participants (79.5%) reported any ocular symptom, with burning eyes being the most frequent ocular symptom (77.2%). General body fatigue was the most common non-ocular symptom of CVS (92.9%), followed by headache (83.5%). Out of 127 participants, 71 men and 30 women had some degree of CVS. Female participants had significantly higher risk of CVS than male participants (p=0.01). Total duration of computer use per day and duration of uninterrupted computer use were significantly associated with the occurrence of CVS (p=0.001 and p=0.008, respectively). No significant association was found between CVS and distance from computer screen (p=0.89), frequency of breaks (p=0.18), or font size (p=0.12). Conclusion: A high prevalence of CVS-related symptoms was observed among computer-using bank workers. Non-ocular symptoms associated with computer use were more common than ocular symptoms (92.9% vs. 77.2%).


Assuntos
Computadores , Feminino , Masculino , Humanos , Prevalência , Estudos Transversais , Paquistão/epidemiologia , Síndrome , Fatores de Risco
19.
PLoS One ; 17(11): e0275688, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36350791

RESUMO

Automation has played a key role in improving the safety, accuracy, and efficiency of manufacturing and industrial processes and has the potential to greatly increase throughput in the life sciences. However, the lack of accessible entry-point automation hardware in life science research and STEM education hinders its widespread adoption and development for life science applications. Here we investigate the design of a low-cost (~$150) open-source DIY Arduino-controlled liquid handling robot (LHR) featuring plastic laser-cut parts. The robot moves in three axes with 0.5 mm accuracy and reliably dispenses liquid down to 20 µL. The open source, modular design allows for flexibility and easy modification. A block-based programming interface (Snap4Arduino) further extends the accessibility of this robot, encouraging adaptation and use by educators, hobbyists and beginner programmers. This robot was co-designed with teachers, and we detail the teachers' feedback in the context of a qualitative study. We conclude that affordable and accessible LHRs similar to this one could provide a useful educational tool to be deployed in classrooms, and LHR-based curricula may encourage interest in STEM and effectively introduce automation technology to life science enthusiasts.


Assuntos
Disciplinas das Ciências Biológicas , Robótica , Computadores , Automação , Currículo
20.
Artigo em Inglês | MEDLINE | ID: mdl-36361190

RESUMO

Patients with mild traumatic brain injury (MTBI) with intracerebral hemorrhage (ICH), particularly those at higher risk of having ICH progression, are typically prescribed a second head Computer Tomography (CT) scan to monitor the disease development. This study aimed to evaluate the role of a repeat head CT in MTBI patients at a higher risk of ICH progression by comparing the intervention rate between patients with and without ICH progression. METHODS: 192 patients with MTBI and ICH were treated between November 2019 to December 2020 at a single level II trauma center. The Glasgow Coma Scale (GCS) was used to classify MTBI, and initial head CT was performed according to the Canadian CT head rule. Patients with a higher risk of ICH progression, including the elderly (≥65 years old), patients on antiplatelets or anticoagulants, or patients with an initial head CT that revealed EDH, contusional bleeding, or SDH > 5 mm, and multiple ICH underwent a repeat head CT within 12 to 24 h later. Data regarding types of intervention, length of stay in the hospital, and outcome were collected. The risk of further neurological deterioration and readmission rates were compared between these two groups. All patients were followed up in the clinic after one month or contacted via phone if they did not return. RESULTS: 189 patients underwent scheduled repeated head CT, 18% had radiological intracranial bleed progression, and 82% had no changes. There were no statistically significant differences in terms of intervention rate, risk of neurological deterioration in the future, or readmission between them. CONCLUSION: Repeat head CT in mild TBI patients with no neurological deterioration is not recommended, even in patients with a higher risk of ICH progression.


Assuntos
Concussão Encefálica , Humanos , Idoso , Canadá , Tomografia Computadorizada por Raios X/métodos , Hemorragia Cerebral/diagnóstico por imagem , Computadores , Encéfalo , Estudos Retrospectivos
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