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101.
Cowie Megan E. Huguet Anna Moore Craig McGrath Patrick J. Rao Sanjay Wozney Lori Kits Olga Stewart Sherry H. 《International journal of mental health and addiction》2021,19(2):579-594
International Journal of Mental Health and Addiction - Behavioral activation (BA) is a well-established treatment for depression, often used as an adjuvant for gambling disorder. Internet-based BA... 相似文献
102.
Ranjith Tellis Olga Starobinets Michael Prokle Usha Nandini Raghavan Christopher Hall Tammana Chugh Ekin Koker Siva Chaitanya Chaduvula Christoph Wald Sebastian Flacke 《Journal of digital imaging》2021,34(1):75
Identifying areas for workflow improvement and growth is essential for an interventional radiology (IR) department to stay competitive. Deployment of traditional methods such as Lean and Six Sigma helped in reducing the waste in workflows at a strategic level. However, achieving efficient workflow needs both strategic and tactical approaches. Uncertainties about patient arrivals, staff availability, and variability in procedure durations pose hindrances to efficient workflow and lead to delayed patient care and staff overtime. We present an alternative approach to address both tactical and strategic needs using discrete event simulation (DES) and simulation based optimization methods. A comprehensive digital model of the patient workflow in a hospital-based IR department was modeled based on expert interviews with the incumbent personnel and analysis of 192 days’ worth of electronic medical record (EMR) data. Patient arrival patterns and process times were derived from 4393 individual patient appointments. Exactly 196 unique procedures were modeled, each with its own process time distribution and rule-based procedure-room mapping. Dynamic staff schedules for interventional radiologists, technologists, and nurses were incorporated in the model. Stochastic model simulation runs revealed the resource “computed tomography (CT) suite” as the major workflow bottleneck during the morning hours. This insight compelled the radiology department leadership to re-assign time blocks on a diagnostic CT scanner to the IR group. Moreover, this approach helped identify opportunities for additional appointments at times of lower diagnostic scanner utilization. Demand for interventional service from Outpatients during late hours of the day required the facility to extend hours of operations. Simulation-based optimization methods were used to model a new staff schedule, stretching the existing pool of resources to support the additional 2.5 h of daily operation. In conclusion, this study illustrates that the combination of workflow modeling, stochastic simulations, and optimization techniques is a viable and effective approach for identifying workflow inefficiencies and discovering and validating improvement options through what-if scenario testing. 相似文献
103.
Melissa A Daubert Tina Tailor Olga James Leslee J Shaw Pamela S Douglas Lynne Koweek 《The British journal of radiology》2021,94(1117)
Cardiovascular imaging has significantly evolved since the turn of the century. Progress in the last two decades has been marked by advances in every modality used to image the heart, including echocardiography, cardiac magnetic resonance, cardiac CT and nuclear cardiology. There has also been a dramatic increase in hybrid and fusion modalities that leverage the unique capabilities of two imaging techniques simultaneously, as well as the incorporation of artificial intelligence and machine learning into the clinical workflow. These advances in non-invasive cardiac imaging have guided patient management and improved clinical outcomes. The technological developments of the past 20 years have also given rise to new imaging subspecialities and increased the demand for dedicated cardiac imagers who are cross-trained in multiple modalities. This state-of-the-art review summarizes the evolution of multimodality cardiac imaging in the 21st century and highlights opportunities for future innovation. 相似文献
104.
105.
Irina S. Vasil'eva Galina P. Shumakovich Maria E. Khlupova Roman B. Vasiliev Viktor V. Emets Vera A. Bogdanovskaya Olga V. Morozova Alexander I. Yaropolov 《RSC advances》2020,10(55):33010
The development of novel materials with improved functional characteristics for supercapacitor electrodes is of current concern and calls for elaboration of innovative approaches. We report on an eco-friendly enzymatic synthesis of a composite based on poly(3,4-ethylenedioxythiophene) (PEDOT) and multi-walled carbon nanotubes (MWCNTs). The redox active compound, sodium 1,2-naphthoquinone-4-sulfonate (NQS), was used as a dopant for the backbone of the polymer. Oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT) was catalyzed by a high redox potential laccase from the fungus Trametes hirsuta. Atmospheric oxygen served as an oxidant. A uniform thin layer of NQS-doped PEDOT formed on the surface of MWCNTs as a result of the enzymatic polymerization. The PEDOT–NQS/MWCNT composite showed a high specific capacitance of ca. 575 F g−1 at a potential scan rate of 5 mV s−1 and an excellent cycling stability within a potential window between −0.5 and 1.0 V, which makes it a promising electrode material for high-performance supercapacitors.The use of redox active NSQ as a dopant of PEDOT dramatically increases the specific capacitance and cyclic stability of enzymatically synthesized PEDOT–NSQ/MWCNT composite. 相似文献
106.
Maria R. Konnikova Olga P. Cherkasova Maxim M. Nazarov Denis A. Vrazhnov Yuri V. Kistenev Sergei E. Titov Elena V. Kopeikina Sergei P. Shevchenko Alexander P. Shkurinov 《Biomedical optics express》2021,12(2):1020
The liquid and lyophilized blood plasma of patients with benign or malignant thyroid nodules and healthy individuals were studied by terahertz (THz) time-domain spectroscopy and machine learning. The blood plasma samples from malignant nodule patients were shown to have higher absorption. The glucose concentration and miRNA-146b level were correlated with the sample’s absorption at 1 THz. A two-stage ensemble algorithm was proposed for the THz spectra analysis. The first stage was based on the Support Vector Machine with a linear kernel to separate healthy and thyroid nodule participants. The second stage included additional data preprocessing by Ornstein-Uhlenbeck kernel Principal Component Analysis to separate benign and malignant thyroid nodule participants. Thus, the distinction of malignant and benign thyroid nodule patients through their lyophilized blood plasma analysis by terahertz time-domain spectroscopy and machine learning was demonstrated. 相似文献
107.
Vriz Olga Palatini Paolo Mos Lucio AlSergani Hani Vendramin Igor Livi Ugolino Antonini-Canterin Francesco Magne Julien 《The international journal of cardiovascular imaging》2021,37(5):1659-1668
The International Journal of Cardiovascular Imaging - Aortic valve stenosis (AS) shares similarities with the atherosclerotic process but little is known about the effect of the mechanical... 相似文献
108.
Veldtman Gruschen Possner Mathias Mohty Dania Issa Ziyad Alsaleh Monerah AlMarzoog AlJuhara Thaar Emmanual Shisamma Salam Yezan AlHabdan Mohammed Saleh Alsaied Tarek Rathod Rahul H. Siblini Ghassan Vriz Olga 《The international journal of cardiovascular imaging》2021,37(9):2651-2660
The International Journal of Cardiovascular Imaging - Abnormal atrial mechanics in biventricular circulations have been associated with elevated left heart filling pressures. Similar associations... 相似文献
109.
110.
The duration, contour, and amplitude of atrial flutter wave (f) was studied by electrocardiogram (ECG) and vectorcardiogram (VCG) in 32 patients and was related to the size of the left atrium (LA) measured by the echocardiogram (E). The following ECG parameters were analyzed: (1) the duration of left atrial depolarization, i.e., LA wave; (2) the amplitude of LA wave; (3) the surface area of LA wave; (4) maximum amplitude (A) of f in Leads 2 and V1. There was good correlation between LA size and the duration of depolarization and surface area (p < 0.01), but the maximum amplitude of the f wave in Leads 2 and V1 failed to predict LA size.The post-conversion sinus P wave showed abnormal LA depolarization time (P > 0.12 sec.) in 62 per cent of patients with enlarged left atrium (ELA) and in 43 per cent of patients with normal size LA (NLA).The VCG of the flutter wave revealed two patterns, (1) an eliptical smooth fsÊ loop in 63 per cent of patients with NLA, and (2) distorted fsÊ loop in 67 per cent of patients with ELA.Both VCG patterns were subdivided in two subgroups according to the number and location of conduction delays. The VCG of post-conversion P wave confirmed conduction delays in both groups.We conclude that both the size of the left atrium and conduction delays play a basic role in the duration and contour of left atrial wave. 相似文献