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1.
ARYA Atheroscler ; 20(1): 20-30, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39165854

RESUMO

BACKGROUND: The National Persian Registry of Cardiovascular Disease (N-PROVE) has been established to provide a comprehensive database of cardiovascular diseases in the Iranian community for further investigations and to develop national guidelines for the diagnosis, treatment, and prevention of cardiovascular disease (CVD). As with most clinical registries, a quality control audit is necessary to ensure a comprehensive and accurate registry; the current study aims to assess the validity and quality of the N-PROVE/Angiography/Percutaneous Coronary Intervention (PCI) registry. METHODS: The current cross-sectional quality assessment study serves as an example of data quality assessment in N-PROVE on a sample of patients registered in the N-PROVE/Angiography/PCI registry since 2020. Accordingly, data of 194 patients, including comorbidities, angiography, and angioplasty characteristics, were collected from the N-PROVE/Angiography/PCI registry as the main database and reevaluated by a panel consisting of a cardiologist and two coronary intervention fellowships as a test database. RESULTS: The quality control of the population-based healthcare database, the N-PROVE/PCI, revealed that the average error rate in terms of comorbidities, angiography characteristics, angioplasty characteristics, and in total were 3.8%, 2.3%, 3%, and 3.03%, respectively. CONCLUSION: According to the findings of this study, the N-PROVE/PCI registry had an average error of less than 4% in the assessed dimensions, including comorbidities, angiography, and angioplasty characteristics. Therefore, this registry appears valid and may be used for contemporary epidemiological studies.

2.
ARYA Atheroscler ; 20(2): 31-40, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39170814

RESUMO

BACKGROUND: Percutaneous coronary intervention (PCI) is the gold standard approach to ST-Segment Elevation Myocardial Infarction (STEMI). Fibrinolysis followed by PCI has been recommended. The current study aims to investigate the no-reflow phenomenon incidence in patients undergoing post-thrombolytic therapy PCI. METHODS: This cross-sectional study was conducted on 250 patients with STEMI who primarily received fibrinolytic therapy followed by early (3-24 hours) (n=231) or delayed (> 24 hours) (n=19) PCI. They were also subcategorized into four intervals: <6 hours (n=98), 6-12 hours (n=93), 12-24 hours (n=38), and ≥24 hours (n=21). The demographic and medical data of the patients were retrieved. The Thrombolysis in Myocardial Infarction score (TIMI) was assessed at baseline and at the end of PCI. A TIMI score other than 3 was defined as no-reflow. RESULTS: The incidence of the no-reflow phenomenon was not associated with any of the underlying demographic and medical characteristics of the patients (P-value>0.05). Despite the significantly higher rate of improvement in TIMI grading among those undergoing early PCI (P-value=0.04), as well as within less than 6 hours after thrombolytic therapy (P-value=0.031), the rate of the no-reflow phenomenon did not differ between the groups, neither by sorting them as early versus delayed (P-value=0.518) nor by categorizing them into four intervals (P-value=0.367). CONCLUSION: Based on the findings of the current study, early PCI after fibrinolysis led to significantly improved TIMI flow. However, the incidence of no-reflow did not differ between the groups with early versus delayed post-fibrinolysis PCI.

3.
Sci Rep ; 14(1): 13405, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862707

RESUMO

Miscible gas injection in tight/shale oil reservoirs presents a complex problem due to various factors, including the presence of a large number of nanopores in the rock structure and asphaltene and heavy components in crude oil. This method performs best when the gas injection pressure exceeds the minimum miscibility pressure (MMP). Accordingly, accurate calculation of the MMP is of special importance. A critical issue that needs to be considered is that the phase behavior of the fluid in confined nanopores is substantially different from that of conventional reservoirs. The confinement effect may significantly affect fluid properties, flow, and transport phenomena characteristics in pore space, e.g., considerably changing the critical properties and enhancing fluid adsorption on the pore wall. In this study, we have investigated the MMP between an asphaltenic crude oil and enriched natural gas using Peng-Robinson (PR) and cubic-plus-association (CPA) equations of state (EoSs) by considering the effect of confinement, adsorption, the shift of critical properties, and the presence of asphaltene. According to the best of our knowledge, this is the first time a model has been developed considering all these factors for use in porous media. We used the vanishing interfacial tension (VIT) method and slim tube test data to calculate the MMP and examined the effects of pore radius, type/composition of injected gas, and asphaltene type on the computed MMP. The results showed that the MMP increased with an increasing radius of up to 100 nm and then remained almost constant. This is while the gas enrichment reduced the MMP. Asphaltene presence changed the trend of IFT reduction and delayed the miscibility achievement so that it was about 61% different from the model without the asphaltene precipitation effect. However, the type of asphaltene had little impact on the MMP, and the controlling factor was the amount of asphaltene in the oil. Moreover, although cubic EoSs are particularly popular for their simplicity and accuracy in predicting the behavior of hydrocarbon fluids, the CPA EoS is more accurate for asphaltenic oils, especially when the operating pressure is within the asphaltene precipitation range.

4.
Sci Rep ; 14(1): 14951, 2024 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-38942817

RESUMO

Prostate cancer is one of the most common and fatal diseases among men, and its early diagnosis can have a significant impact on the treatment process and prevent mortality. Since it does not have apparent clinical symptoms in the early stages, it is difficult to diagnose. In addition, the disagreement of experts in the analysis of magnetic resonance images is also a significant challenge. In recent years, various research has shown that deep learning, especially convolutional neural networks, has appeared successfully in machine vision (especially in medical image analysis). In this research, a deep learning approach was used on multi-parameter magnetic resonance images, and the synergistic effect of clinical and pathological data on the accuracy of the model was investigated. The data were collected from Trita Hospital in Tehran, which included 343 patients (data augmentation and learning transfer methods were used during the process). In the designed model, four different types of images are analyzed with four separate ResNet50 deep convolutional networks, and their extracted features are transferred to a fully connected neural network and combined with clinical and pathological features. In the model without clinical and pathological data, the maximum accuracy reached 88%, but by adding these data, the accuracy increased to 96%, which shows the significant impact of clinical and pathological data on the accuracy of diagnosis.


Assuntos
Aprendizado Profundo , Neoplasias da Próstata , Humanos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Masculino , Pessoa de Meia-Idade , Idoso , Redes Neurais de Computação , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética Multiparamétrica/métodos , Processamento de Imagem Assistida por Computador/métodos , Interpretação de Imagem Assistida por Computador/métodos , Irã (Geográfico)
5.
BMC Oral Health ; 24(1): 211, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341526

RESUMO

BACKGROUND: Dental caries, also known as tooth decay, is a widespread and long-standing condition that affects people of all ages. This ailment is caused by bacteria that attach themselves to teeth and break down sugars, creating acid that gradually wears away at the tooth structure. Tooth discoloration, pain, and sensitivity to hot or cold foods and drinks are common symptoms of tooth decay. Although this condition is prevalent among all age groups, it is especially prevalent in children with baby teeth. Early diagnosis of dental caries is critical to preventing further decay and avoiding costly tooth repairs. Currently, dentists employ a time-consuming and repetitive process of manually marking tooth lesions after conducting radiographic exams. However, with the rapid development of artificial intelligence in medical imaging research, there is a chance to improve the accuracy and efficiency of dental diagnosis. METHODS: This study introduces a data-driven model for accurately diagnosing dental decay through the use of Bitewing radiology images using convolutional neural networks. The dataset utilized in this research includes 713 patient images obtained from the Samin Maxillofacial Radiology Center located in Tehran, Iran. The images were captured between June 2020 and January 2022 and underwent processing via four distinct Convolutional Neural Networks. The images were resized to 100 × 100 and then divided into two groups: 70% (4219) for training and 30% (1813) for testing. The four networks employed in this study were AlexNet, ResNet50, VGG16, and VGG19. RESULTS: Among different well-known CNN architectures compared in this study, the VGG19 model was found to be the most accurate, with a 93.93% accuracy. CONCLUSION: This promising result indicates the potential for developing an automatic AI-based dental caries diagnostic model from Bitewing images. It has the potential to serve patients or dentists as a mobile app or cloud-based diagnosis service (clinical decision support system).


Assuntos
Cárie Dentária , Criança , Lactente , Humanos , Cárie Dentária/diagnóstico por imagem , Inteligência Artificial , Irã (Geográfico) , Redes Neurais de Computação , Dente Decíduo
6.
Polymers (Basel) ; 15(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37688153

RESUMO

Despite being primarily categorized as non-autonomous self-healing polymers, we demonstrate the ability of Diels-Alder polymers to heal macroscopic damages at room temperature, resulting in complete restoration of their mechanical properties within a few hours. Moreover, we observe immediate partial recovery, occurring mere minutes after reuniting the fractured surfaces. This fast room-temperature healing is accomplished by employing an off-stoichiometric maleimide-to-furan ratio in the polymer network. Through an extensive investigation of seven Diels-Alder polymers, the influence of crosslink density on self-healing, thermal, and (thermo-)mechanical performance was thoroughly examined. Crosslink density variations were achieved by adjusting the molecular weight of the monomers or utilizing the off-stoichiometric maleimide-to-furan ratio. Quasistatic tensile testing, dynamic mechanical analysis, dynamic rheometry, differential scanning calorimetry, and thermogravimetric analysis were employed to evaluate the individual effects of these parameters on material performance. While lowering the crosslink density in the polymer network via decreasing the off-stoichiometric ratio demonstrated the greatest acceleration of healing, it also led to a slight decrease in (dynamic) mechanical performance. On the other hand, reducing crosslink density using longer monomers resulted in faster healing, albeit to a lesser extent, while maintaining the (dynamic) mechanical performance.

7.
Sci Rep ; 13(1): 8077, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37202448

RESUMO

Gas injection can increase oil recovery because the gas-oil interfacial tension is less than the water-oil interfacial tension (IFT) and tends to zero in the miscibility state. However, little information has been provided on the gas-oil movement and penetration mechanisms in the fracture system at the porosity scale. The IFT of oil and gas in the porous medium changes and can control oil recovery. In this study, the IFT and the minimum miscibility pressure (MMP) are calculated using the cubic Peng-Robinson equation of state that has been modified using the mean pore radius and capillary pressure. The calculated IFT and MMP change with the pore radius and capillary pressure. To investigate the effect of a porous medium on the IFT during the injection of CH4, CO2, and N2 in the presence of n-alkanes and for validation, measured experimental values in references have been used. According to the results of this paper, changes in IFT vary in terms of pressure in the presence of different gases and, the proposed model has good accuracy for measuring the IFT and the MMP during the injection of hydrocarbon gases and CO2. In addition, as the average radius of the pores gets smaller, the interfacial tension tends to lower values. This effect is different with increasing the mean size of interstice in two different intervals. In the first interval, i.e. the Rp from 10 to 5000 nm, the IFT changes from 3 to 10.78 mN/m and in the second interval, i.e. the Rp from 5000 nm to infinity, the IFT changes from 10.78 to 10.85 mN/m. In other words, increasing the diameter of the porous medium to a certain threshold (i.e. 5000 nm) increases the IFT. As a rule, changes in IFT affected by exposure to a porous medium affect the values of the MMP. In general, IFT decreases in very fine porous media, causing miscibility at lower pressures.

8.
Sci Rep ; 13(1): 6573, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37085713

RESUMO

Gas injection is one of the most common enhanced oil recovery techniques in oil reservoirs. In this regard, pure gas, such as carbon dioxide (CO2), nitrogen (N2), and methane (CH4) was employed in EOR process. The performance of pure gases in EOR have been investigated numerically, but till now, numerical simulation of injection of rich gases has been scared. As rich gases are more economical and can result in acceptable oil recovery, numerical study of the performance of rich gases in EOR can be an interesting subject. Accordingly, in the present work the performance of rich gases in the gas injection process was investigated. Methane has been riched in liquefied petroleum gas (LPG), natural gas liquid (NGL), and Naphtha. Afterwards, the process of gas injection was simulated and the effect of injection fluids on the relative permeability, saturation profile of gas, and fractional flow of gas was studied. Our results showed that as naphtha is a heavier gas than the two other ones, IFT of oil-rich gas with naphtha is lower than other two systems. Based our results, gas oil ratio (GOR) and injection pressure did not affect the final performance of injection gas that has been riched in NGL and LPG. However, when GOR was 1.25 MSCF/STB, rich gas with naphtha moved with a higher speed in the domain and the relative permeability of each fluid and fractional flow of gas were affected. The same result was achieved at higher injection pressure. When injection pressure was 2000 psi, movement of gas with higher speed in the domain, alteration of relative permeability and changes in the fractional flow of gas were obvious. Therefore, based on our result, injection of naphtha with low pressure and high GOR was suggested for considered oil.

9.
ARYA Atheroscler ; 19(6): 18-26, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38883851

RESUMO

INTRODUCTION: In recent years, transradial cardiac catheterization has become the preferred method. However, it can result in a significant complication known as radial artery occlusion (RAO). The medical management of RAO remains controversial, especially with the emergence of novel oral anticoagulants. Nevertheless, there is limited data on the use of these agents for treating RAO, which is the focus of this study using apixaban. METHOD: This pilot double-blinded randomized clinical trial involved 30 patients who developed RAO following transradial coronary angiography. The patients were randomly assigned to receive either apixaban (2.5 mg twice daily) or a conservative approach for 30 days. Doppler ultrasonography was performed at baseline and at the end of the intervention to assess radial artery diameter and the resolution of arterial patency. Demographic, medical, medication, and clinical characteristics were collected. RESULTS: The mean age of the studied population was 59.43±12.14 years, and the majority were males (60%). Radial artery resolution was observed in 21 (70%) patients, independent of medication use. There was no significant association between resolution and age (P-value=0.62), gender (P-value=0.74), body mass index (P-value=0.23), smoking (P-value=0.64), diabetes (P-value=0.999), hypertension (P-value=0.74), statins (P-value=0.999), antiplatelet therapy (P-value=0.999), length of angiography (P-value=0.216), or follow-up arterial diameter (P-value=0.304). Recanalization occurred in 13 (86.7%) cases in the apixaban treatment group, compared to 8 (53.3%) individuals in the control group, indicating a significant difference (P-value=0.046). CONCLUSION: The study findings suggest no demographic, medical, medication, or clinical factors were associated with arterial recanalization. However, a one-month treatment with apixaban at a dose of 2.5 mg twice daily appeared to be effective.

10.
ARYA Atheroscler ; 19(6): 36-43, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38883855

RESUMO

INTRODUCTION: Primary percutaneous coronary intervention (PPCI) is the gold standard approach to restore blood flow in ST-segment elevation myocardial infarction (STEMI); however, the no-reflow phenomenon as a potential complication of PPCI can worsen the outcomes. It has been hypothesized that adjunctive prophylactic intracoronary infusion of low-dose fibrinolytic might improve the PPCI outcomes; however, this theory is a matter of debate. The current study aims to investigate the value of adjunctive prophylactic intracoronary low-dose alteplase to prevent the no-reflow phenomenon in patients with STEMI. METHOD: This case-control study was conducted on 80 STEMI patients who underwent PPCI. The patients were assigned into the case group who were intervened by 10 mg adjunctive intracoronary alteplase immediately at the end of the balloon angioplasty (n=40) and controls (n=40) who underwent conventional PPCI only. The angioplasty-associated outcomes including final TIMI score, need for no-reflow treatment, ST-segment resolution, post-PPCI complications, and death were compared between the groups. RESULTS: Alteplase use was accompanied by significantly improved final TIMI flow scores (P-value<0.001) and fewer requirements for no-reflow treatments (P-value<0.001); however, it did not improve the ST-segment resolution (P-value=0.491). The mortality rate and post-angioplasty complications did not differ between the groups (P-value>0.05). CONCLUSION: Based on the findings of this study, adjunctive infusion of low-dose intracoronary alteplase during PPCI could not efficiently prevent the no-reflow phenomenon. Although the final TIMI flow and need for post-stenting no-reflow treatment improved, ST-segment resolution did not occur dramatically. Given that, this approach requires further investigations and should be considered cautiously.

11.
ARYA Atheroscler ; 19(4): 1-10, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38881997

RESUMO

INTRODUCTION: The use of allopurinol has shown promising outcomes in reducing oxidative processes responsible for atherogenic-related cardiovascular events. The current study aims to assess the effects of high-dose allopurinol on the post-revascularization coronary blood flow and inflammatory biomarkers in patients with non-ST segment elevated myocardial infarction (NSTEMI). METHOD: Eighty NSTEMI patients were randomly divided into two groups: the intervention group (n=40), medicated with a high loading dose of 600 mg allopurinol before the coronary angiography, and the control group (n=40), treated with a placebo. The highly sensitive C-reactive protein (hs-CRP) was measured at baseline and within 24 hours after the cardiac interventions and compared between the case and control groups. Post percutaneous coronary intervention (PCI) Thrombolysis in Myocardial Infarction (TIMI) flow grading was also evaluated as a revascularization endpoint. RESULTS: The two groups of the study were similar in terms of demographic, clinical, laboratory, and angiographic characteristics (P-value>0.050). The assessed TIMI flow was similar between the cases and the controls both prior to (P-value=0.141) and after (P-value=0.395) the coronary angioplasty. The hs-CRP (P-value=0.016) was significantly higher in the control group. Post-angiographic assessment of hs-CRP revealed an insignificant difference between the groups (P-value=0.104). CONCLUSION: In conclusion, premedication with a high dose of allopurinol in NSTEMI patients did not affect the inflammatory biomarker or the revascularization endpoint.

12.
ARYA Atheroscler ; 19(5): 35-42, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38882650

RESUMO

INTRODUCTION: Cerebral ischemia and coronary artery disease (CAD), the major leading causes of mortality and morbidity worldwide, are pathophysiologically interrelated. Cerebral ischemic events are categorized as large or small vessels disease. The current study compares the factors related to CAD events incidence following ischemic large versus small disease CVA. METHOD: The current cohort study was conducted on 225 patients with ischemic stroke in two groups of large (n=75) and small (n=150) vessel disease during 2018-19. The patients' demographic, medical, and clinical characteristics were recruited. They were followed for three years regarding the incidence of CAD events, including ST-elevation myocardial infarction (STEMI), non-ST elevation myocardial infarction (NSTEMI), unstable angina (UA), and sudden cardiac death (SCD). Data about the coronary angiography, computed tomography angiography (CTA), Single Photon Emission Computed Tomography (SPECT), and the therapeutic approach were gathered. RESULTS: There were insignificant differences between the patients with small versus large vessels CVA in terms of ACS incidence (P-value=0.105), type of the events (P-value=0.836), angiographic (P-value=0.671), SPECT (P-value=0.99) and CTA findings (P-value>0.99) and approached CAD (P-value=0.728). Cox regression assessments revealed an increased risk of CAD events due to large versus small vessels disease after adjustments for hypertension, diabetes mellitus, dyslipidemia, re-stroke, and the previous history of IHD (HR=2.005, 95%CI: 1.093-2.988, P-value=0.021). CONCLUSION: According to the findings of this study, large-vessel involvement in an ischemic stroke was associated with more than a two-fold increase in the three-year probability of ischemic heart disease incidencet.

13.
J Res Med Sci ; 27: 45, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35968214

RESUMO

Background: Plaque instability is a leading cause of morbidity and mortality in coronary artery disease (CAD) patients. Numerous efforts have been made to figure out and manage unstable plaques prior to major cardiovascular events incidence. The current study aims to assess the values of the atherogenic index of plasma (AIP) to detect unstable plaques. Materials and Methods: The current case-control study was conducted on 435 patients who underwent percutaneous coronary intervention due to chronic stable angina (stable plaques, n = 145) or acute coronary syndrome (unstable plaques, n = 290). The demographic, comorbidities, chronic medications, biochemical and hematological characteristics of the patients were entered into the study checklist. The baseline AIP was measured according to the formula of triglycerides/high-density lipoprotein logarithm. Binary logistic regression was applied to investigate the standalone association of AIP with plaque instability. Receiver operating curve (ROC) was depicted to determine a cut-off, specificity, and sensitivity of AIP in unstable plaques diagnosis. Results: AIP was an independent predictor for atherogenic plaque unstability in both crude (odds ratio [OR]: 3.677, 95% confidence interval [CI]: 1.521-8.890; P = 0.004) and full-adjusted models (OR: 15, 95% CI: 2.77-81.157; P = 0.002). According to ROC curve, at cut-point level of 0.62, AIP had sensitivity and specificity of 89.70% and 34% to detect unstable plaques, respectively (area under the curve: 0.648, 95% CI: 0.601-0.692, P < 0.001). Conclusion: According to this study, at the threshold of 0.62, AIP as an independent biomarker associated with plaque instability can be considered a screening tool for patients at increased risk for adverse events due to unstable atherosclerotic plaques.

14.
Caspian J Intern Med ; 13(3): 527-532, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35974934

RESUMO

Background: Beyond the adverse effects of hyperphosphatemia in patients with chronic kidney disease (CKD(, hypophosphatemia has also been proposed as a common challenge after dialysis. Therefore, the present study aimed to evaluate the serum phosphate level immediately after hemodialysis (HD) and its association with some clinical complications in CKD patients. Methods: The present cross-sectional study was conducted on 54 eligible CKD patients undergoing regular hemodialysis. Blood samples were taken, prior to the start and immediately after the end of hemodialysis to determine the serum levels of urea, creatinine, sodium, potassium, phosphorus, PTH, blood sugar and albumin. Moreover, the clinical complications of patients including muscle cramps, nausea, vomiting, headache, confusion, weakness and inability to speak are assessed by a questionnaire, before and after HD. Results: As we expected, the mean of serum creatinine, urea and phosphate levels significantly decreased after dialysis. Post-dialysis hypophosphatemia was graded as mild (3.5 > P ≥ 2.5 mg/dl), moderate (2.5 > P ≥ 1 mg/dl), and severe (<1 mg/dl) based on serum phosphate levels. The frequency of mild and moderate hypophosphatemia was 39.2% and 45.1 %, respectively. None of the participants had severe hypophosphatemia and 13.7% had normal phosphate levels. There was a significant correlation between post-dialysis hypophosphatemia and incidence of nausea and confusion after adjusting for confounding factors. Conclusion: To our knowledge, this is the first time that the possible association of some of the post-dialysis clinical complications with hypophosphatemia was investigated. Future large-scale studies are required to confirm the association of post-dialysis hypophosphatemia with clinical complications.

15.
Percept Mot Skills ; 129(3): 488-512, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35395926

RESUMO

Researchers have been divided on the efficacy of computerized cognitive training (CCT) for enhancing spatial abilities, transfer of training, and improving malleability of skills. In this study, we assessed the effects of puzzle video game training on subsequent mental rotation (MR) and mental folding (MF) performance among adults with no cognitive impairment. We assessed participants at baseline with the Shepard-Metzler MR test followed by the differential aptitude test: space relations MF test (i.e., far transfer). We ranked participants' skills on these pre-tests and used a matching technique to form two skill groups from which we then randomly assigned members of each skill group either to an experimental group or a wait-list control group. The experimental group played two puzzle video games closely related to two-dimensional and three-dimensional MR tasks during 4-week training sessions (total of 12 hour of video games). Post-training, participants completed the MR and MF tests again. Two months later, we re-assessed only the experimental group's spatial skills to explore the sustainability of the trained performance. In addition to response times (RT) and error scores (ES), reported separately, we combined these variables into rate correct scores (RCS) to form an integrated measure of potential speed-accuracy trade-offs (SAT). As a result, we did not find significant improvements in MR performance from CCT engagement, nor did participants show a transfer of skills obtained by practicing MR-related puzzle games to a MF task. Based on the current findings, we urge caution when proposing a game-based intervention as a training tool to enhance spatial abilities. We argue that separately interpreting individual test measures can be misleading, as they only partially represent performance. In contrast, composite scores illuminate underlying cognitive strategies and best determine whether an observed improvement is attributable to enhanced capacities or individual heuristics and learned cognitive shortcuts.


Assuntos
Jogos de Vídeo , Adulto , Cognição/fisiologia , Humanos , Aprendizagem , Tempo de Reação
16.
IEEE Trans Cybern ; 52(9): 8642-8654, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33710970

RESUMO

In this article, a distributed adaptive model-free control algorithm is proposed for consensus and formation-tracking problems in a network of agents with completely unknown nonlinear dynamic systems. The specification of the communication graph in the network is incorporated in the adaptive laws for estimation of the unknown linear and nonlinear terms, and in the online updating of the elements in the main controller gain matrix. The decentralized control signal at each agent in the network requires information about the states of the leader agent, as well as the desired formation variables of the agents in a local coordinate frame. These two sets of variables are provided at each agent by utilizing two recently proposed distributed observers. It is shown that only a spanning-tree rooted at the leader agent is enough for the convergence and stability of the proposed cooperative control and observer algorithms. Two simulation studies are provided to evaluate the performance of the proposed algorithm in comparison with two state-of-the-art distributed model-free control algorithms. With lower control effort as well as fewer offline gain tuning, the same level of consensus errors is achieved. Finally, the application of the proposed solution is studied in the formation-tracking control of a team of autonomous aerial mobile robots via simulation results.

17.
Adv Med Sci ; 66(2): 418-423, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34562749

RESUMO

PURPOSE: Cardiovascular events (CVE) are the most prominent cause of death worldwide. Therefore, achieving a precise affordable index for the prediction of healthy cases at increased risk of CVE in early stages and subsequently lessening the rate of CVE mortality is a critical goal of healthcare systems. We aimed to assess the value of Atherogenic index of plasma (AIP) in the prediction of CVE and mortality through a 15-year cohort study. MATERIALS/METHODS: This study was conducted on 6323 over 35-year-old healthy adults from 2001 to 2016. The baseline AIP was measured based on the formula of TG to HDL logarithm and divided into three subgroups of low, intermediate, and high risk of CVD, as <0.11, 0.11-0.21, and ≥0.21, respectively. Eventually, the association of AIP with sociodemographic, lifestyle, traditional CVE-related factors and CVE-induced mortality was evaluated. RESULTS: The multiple cox regression study of AIP values for the prediction of CVE incidence revealed a significant association (OR: 1.57, 95%CI: 1.33-1.85); similar remarkable associations were achieved by controlling age and sex (OR: 1.55, 95%CI: 1.31-1.83), sociodemographic factors (OR: 1.51, 95%CI: 1.29-1.79), sociodemographic plus lifestyle factors (OR: 1.54, 95%CI: 1.30-1.81) and sociodemographic, lifestyle and the traditional CVE-related factors (OR: 1.28, 95%CI: 1.07-1.54). The Kaplan-Meier survival study showed a significant association between AIP levels and CVE-related mortality (p <0.001). CONCLUSION: In conclusion, AIP is an independent stand-alone factor for the prediction of developing CVE and its-related mortality.


Assuntos
Doenças Cardiovasculares , Fatores Sociodemográficos , Adulto , Doenças Cardiovasculares/diagnóstico , Estudos de Coortes , Humanos , Incidência , Fatores de Risco
18.
Polymers (Basel) ; 13(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34372124

RESUMO

In recent work, the thermoreversible Diels-Alder reaction between furan and maleimide functional groups has been studied extensively in the context of self-healing elastomers and thermosets. To elaborate the influence of the stoichiometric ratio between the maleimide and furan reactive groups on the thermomechanical properties and viscoelastic behavior of formed reversible covalent polymer networks, a series of Diels-Alder-based networks with different stoichiometric ratios was synthesized. Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and dynamic rheology measurements were performed on the reversible polymer networks, to relate the reversible network structure to the material properties and reactivity. Such knowledge allows the design and optimization of the thermomechanical behavior of the reversible networks for intended applications. Lowering the maleimide-to-furan ratio creates a deficit of maleimide functional groups, resulting in a decrease in the crosslink density of the system, and a consequent decrease in the glass transition temperature, Young's modulus, and gel transition temperature. The excess of unreacted furan in the system results in faster reaction and healing kinetics and a shift of the reaction equilibrium.

19.
Comput Commun ; 176: 234-248, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34149118

RESUMO

The novel 2019 coronavirus disease (COVID-19) has infected over 141 million people worldwide since April 20, 2021. More than 200 countries around the world have been affected by the coronavirus pandemic. Screening for COVID-19, we use fast and inexpensive images from computed tomography (CT) scans. In this paper, ResNet-50, VGG-16, convolutional neural network (CNN), convolutional auto-encoder neural network (CAENN), and machine learning (ML) methods are proposed for classifying Chest CT Images of COVID-19. The dataset consists of 1252 CT scans that are positive and 1230 CT scans that are negative for COVID-19 virus. The proposed models have priority over the other models that there is no need of pre-trained networks and data augmentation for them. The classification accuracies of ResNet-50, VGG-16, CNN, and CAENN were obtained 92.24%, 94.07%, 93.84%, and 93.04% respectively. Among ML classifiers, the nearest neighbor (NN) had the highest performance with an accuracy of 94%.

20.
Adv Respir Med ; 89(2): 115-123, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33966259

RESUMO

INTRODUCTION: Investigations have described a correlation between the severity of heart failure and the severity of pulmonary function abnormalities. In this study, we investigated the association of resting spirometric parameters, lung diffusion for carbon monoxide (DLCO), and the transfer coefficient (KCO) with hemodynamic variables and outcomes in a cohort of heart transplant candidates. MATERIAL AND METHODS: Between January 2018 and January 2020, a total of 100 patients with advanced heart failure who were scheduled for right heart catheterization (RHC) as a pre-transplant evaluation measure were enrolled. Spirometry and DLCO were performed in all patients within 24 hours of their RHC. All selected patients were followed for a median (IQR) time of 6 (2-12) months. The end points of interest were heart failure-related mortality and a combined event involving HF-related mortality, heart transplantation (HTX), and need for the placement of a left ventricular assist device (LVAD). RESULTS: Among 846 patients scheduled for RHC, a total of 100 patients (25% female) with a mean (SD) age of 38.5 (12.8) were enrolled. There was a significant correlation between FEV1/FVC and CVP (r = -0.22, p = 0.02), PCWP (r = -0.4, p < 0.001), mPAP (r = -0.45, p < 0.001), and PVR (r = -0.32, p = 0.001). The cardiac output correlated with DLCO (r = 0.3, p = 0.008). Spirometry parameters, DLCO parameters, and hemodynamic parameters did not correlate with the combined event. Among the several variables, only PVR had an independent association with the combined event. CONCLUSION: Both mechanical and gas diffusion parameters of the lung were not associated with outcomes in the homogeneous group of heart transplant candidates.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Transplante de Coração , Pulmão/fisiopatologia , Testes de Função Respiratória/estatística & dados numéricos , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Circulação Pulmonar , Listas de Espera
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