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The problem of identifying the parameters of a DC motor is considered. The presence of measurement errors of currents and voltages leads to errors in both input and output signals. Existing methods for identifying the parameters of a DC motor do not take into account the presence of errors in both the output and input signals. A discrete model of a DC motor designed for use in digital systems is explored. One of the advantages of this model is the reduction of the problem of parameter estimation to two reduced dimension problems. Reducing the dimension of the problems being solved improves their conditionality and reduces sensitivity to measurement errors. A new method for identifying the parameters of DC motor models is proposed. Parameter estimates are found based on the extended method of instrumental variables. To find estimates, the use of extended equivalent systems of equations is proposed. Extended equivalent systems make it possible to reduce the condition numbers. The conducted numerical experiments showed the advantage of the proposed algorithm over the least squares. The results of the work can be applied in the development of predictive diagnostic systems. The use of the proposed method for identifying the parameters of a DC motor also makes it possible to reduce the requirements for measuring devices due to less sensitivity to measurement errors.

The NCCN Guidelines for Lung Cancer Screening recommend criteria for selecting individuals for screening and provide recommendations for evaluation and follow-up of lung nodules found during initial and subsequent screening. These NCCN Guidelines Insights focus on recent updates to the NCCN Guidelines for Lung Cancer Screening.

BNP elevation in patients with AF is observed in the absence of heart failure; however, prior mechanistic studies have not included direct left atrial pressure measurements. This study sought to understand how emptying function of the left atrial appendage (LAA) and LAA dimension contributes to brain-natriuretic peptide elevations (BNP) in atrial fibrillation (AF) accounting for left atrial pressure (LAP).132 patients referredfor left atrial appendage occlusion (LAAO) were prospectively enrolled in this study. BNP levels and LAP were measured just before LAAO. Statistical analysis considered BNP, rhythm at time of procedure, LAP, LAA morphology, LAA size (ostial diameter, depth, volume), LAA emptying velocity, CHADS2-VASc score, body mass index (BMI), left ventricular ejection fraction (LVEF), estimated glomerular filtration rate (eGFR), and obstructive sleep apnea (OSA) diagnosis as covariates.Bivariate statistical analysis demonstrated positive associations with age, LAA ostial diameter, depth, and volume, LAP, AF status at time of measurement, OSA, and CHADS2-VASc score. BNP was negatively associated with LVEF, eGFR, LAA emptying velocity and BMI. With multivariate logistic regression including LAP as covariate, significant relationships between BNP and AF/AFL(OR 1.99 [1.03, 3.85]), LAP (OR 1.13 [1.06, 1.20]), LAA diameter (OR 1.14 [1.03, 1.27]), LAA depth (OR 1.14 [1.07, 1.22]), and LAA emptying velocity (OR 0.97 [0.96,0.99]) were observed; however, no significant associations were seen with LAA morphology or CHADS2-VASc score.BNP elevations in AF are associated with LAA size and function, but not CHADS2-VASc score or appendage morphology after accounting for changes in LAP.

Study Design: case series. Objective: The restoration of defects in a single procedure with microvascular free flap reconstruction has become a mainstay of head and neck surgery. Yet in patients with complex defects and pre-existing comorbid medical conditions, a staged-reconstructive approach can enhance the safety of the procedure and improve the patient’s outcome. Methods: We present 3 representative case examples of a larger series of patients who underwent reconstruction of major defects and discuss the usefulness of a staged-reconstructive approach in the management of complex patients. Results: All 3 patients, with an existing composite defect in the setting of prior radiation therapy, underwent successful staged-reconstructive surgery using a variety of free tissue and regional flap transfers. Conclusions: A staged approach facilitates the reconstruction of complex composite defects, increases vessel availability, and mitigates the risk of flap failure. Although this approach commits the patient to multiple procedures and a more prolonged plan of care, it is preferable to 1 operation in specific complex situations with adverse, high-risk clinical features.

Supplemental Digital Content is available in the text., After deployment to Southwest Asia, some soldiers develop persistent respiratory symptoms, including exercise intolerance and exertional dyspnea. We identified 50 soldiers with a history of deployment to Southwest Asia who presented with unexplained dyspnea and underwent an unrevealing clinical evaluation followed by surgical lung biopsy. Lung tissue specimens from 17 age-matched, nonsmoking subjects were used as controls. Quantitative histomorphometry was performed for evaluation of inflammation and pathologic remodeling of small airways, pulmonary vasculature, alveolar tissue and visceral pleura. Compared with control subjects, lung biopsies from affected soldiers revealed a variety of pathologic changes involving their distal lungs, particularly related to bronchovascular bundles. Bronchioles from soldiers had increased thickness of the lamina propria, smooth muscle hypertrophy, and increased collagen content. In adjacent arteries, smooth muscle hypertrophy and adventitial thickening resulted in increased wall-to-lumen ratio in affected soldiers. Infiltration of CD4 and CD8 T lymphocytes was noted within airway walls, along with increased formation of lymphoid follicles. In alveolar parenchyma, collagen and elastin content were increased and capillary density was reduced in interalveolar septa from soldiers compared to control subjects. In addition, pleural involvement with inflammation and/or fibrosis was present in the majority (92%) of soldiers. Clinical follow-up of 29 soldiers (ranging from 1 to 15 y) showed persistence of exertional dyspnea in all individuals and a decline in total lung capacity. Susceptible soldiers develop a postdeployment respiratory syndrome that includes exertional dyspnea and complex pathologic changes affecting small airways, pulmonary vasculature, alveolar tissue, and visceral pleura.

OBJECTIVES/HYPOTHESIS The primary objective of this study was to assess the safety of parathyroidectomy during pregnancy as treatment for hyperparathyroidism (HPTH) in comparison to nonsurgical management plans. Secondary outcomes involved analyzing the safety of surgery in the third trimester and the benefit of operating on asymptomatic pregnant patients. STUDY DESIGN Systematic review. METHODS PRISMA-guided systematic review of all cases of primary hyperparathyroidism during pregnancy published in peer-reviewed English journals on PubMed/MEDLINE, EMBASE, and SCOPUS from 1980 to 2020. RESULTS A total of 75 manuscripts were included in this review describing 382 cases of gestational hyperparathyroidism. The median maternal age was 31 years. Overall, 108 cases (28.3%) underwent parathyroidectomy during pregnancy while 274 cases (71.7%) were treated nonsurgically. The majority of surgeries took place during the second trimester (67.6%). Complications and/or deaths were less likely to occur after surgery in the second trimester (4.48%) as compared to surgery in the third trimester (21.1%). Nine surgically treated cases resulted in infant complications and/or death; however, none of these nine cases had any surgical complications. Despite these complications, the overall infant complication rate for patients who underwent surgical treatment remained lower than that of patients treated with conservative therapy (9.1% vs. 38.9%). CONCLUSIONS This review suggests that for all pregnant patients with diagnosed HPTH, parathyroidectomy should be considered regardless of symptomatology. Our data suggest that parathyroidectomy is associated with fewer risks than more conservative treatments and results in better fetal outcomes. Surgery during the third trimester is feasible and surgery should be considered in both symptomatic and asymptomatic patients. Laryngoscope, 131:1915-1921, 2021.

SUMMARY: The osteomyocutaneous iliac crest free flap is a reconstructive option for segmental mandibular or complex palatomaxillary defects. Familiarity with the radiographic appearance of free flaps such as the iliac crest is necessary for the postoperative evaluation of patients after mandibular, maxillary, or palatal reconstructions because it allows radiologists to properly monitor and interpret the appearance of the flap over time. This study presents a retrospective review of 5 patients who underwent palatomaxillary reconstruction with an iliac crest free flap at our institution. The imaging appearances of the 5 patients were analyzed to determine the key radiographic characteristics of a healthy and successful iliac crest free flap. Radiographic fluency with the imaging appearance of the iliac crest free flap, as well as the new anatomy of the region in the postoperative period, will allow for better interpretation of the flap appearance on imaging and will prevent false identification of tumor recurrence.

BackgroundA systems-level approach to smoking cessation treatment may optimize healthcare provider adherence to guidelines. Institutions such as the Veterans Health Administration (VHA) are unique in their systematic approach, but comparisons of provider behavior in different healthcare systems are limited.MethodsWe surveyed general medicine providers and specialists in a large academic health center (AHC) and its affiliated VHA in the Mid-South in 2017 to determine the cross-sectional association of healthcare system in which the provider practiced (exposure: AHC versus VHA) with self-reported provision of evidence-based smoking cessation treatment (delivery of counseling plus smoking cessation medication or referral) at least once in the past 12 months (composite outcome). Multivariable logistic regression with adjustment for specialty was performed in 2017–2019.ResultsOf 625 healthcare providers surveyed, 407 (65%) responded, and 366 (59%) were analyzed. Most respondents practiced at the AHC (273[75%] vs VHA 93[25%]) and were general internists (215[59%]); pulmonologists (39[11%]); hematologists/oncologists (69[19%]); and gynecologists (43[12%]). Most respondents (328[90%]) reported the primary outcome. The adjusted odds of evidence-based smoking cessation treatment were higher among VHA vs. AHC healthcare providers (aOR = 4.3; 95% CI 1.3–14.4;p = .02). Health systems differed by provision of individual treatment components, including smoking cessation medication use (98% VHA vs. 90% AHC,p = 0.02) and referral to smoking cessation services (91% VHA vs. 65% AHCp = 0.001).ConclusionsVHA healthcare providers were significantly more likely to provide evidence-based smoking cessation treatment compared to AHC healthcare providers. Healthcare systems’ prioritization of and investment in smoking cessation treatment is critical to improving providers’ adherence to guidelines.

The COVID-19 pandemic is stimulating improvements in remote access and use of technology in conservation-related programs and research. In many cases, organizations have intended for remote engagement to benefit groups that have been marginalized in the sciences. But are they? It is important to consider how remote access affects social justice in conservation biology-i.e., the principle that

The Early Detection Research Network’s (EDRN) purpose is to discover, develop and validate biomarkers and imaging methods to detect early-stage cancers or at-risk individuals. The EDRN is composed of sites that fall into four categories: Biomarker Developmental Laboratories (BDL), Biomarker Reference Laboratories (BRL), Clinical Validation Centers (CVC) and Data Management and Coordinating Centers. Each component has a crucial role to play within the mission of the EDRN. The primary role of the CVCs is to support biomarker developers through validation trials on promising biomarkers discovered by both EDRN and non-EDRN investigators. The second round of funding for the EDRN Lung CVC at Vanderbilt University Medical Center (VUMC) was funded in October 2016 and we intended to accomplish the three missions of the CVCs: To conduct innovative research on the validation of candidate biomarkers for early cancer detection and risk assessment of lung cancer in an observational study; to compare biomarker performance; and to serve as a resource center for collaborative research within the Network and partner with established EDRN BDLs and BRLs, new laboratories and industry partners. This report outlines the impact of the VUMC EDRN Lung CVC and describes the role in promoting and validating biological and imaging biomarkers.

With the rapid development of image acquisition and storage, multiple images per class are commonly available for computer vision tasks (e.g., face recognition, object detection, medical imaging, etc.). Recently, the recurrent neural network (RNN) has been widely integrated with convolutional neural networks (CNN) to perform image classification on ordered (sequential) data. In this paper, by permutating multiple images as multiple dummy orders, we generalize the ordered “RNN+CNN” design (longitudinal) to a novel unordered fashion, called Multi-path x-D Recurrent Neural Network (MxDRNN) for image classification. To the best of our knowledge, few (if any) existing studies have deployed the RNN framework to unordered intra-class images to leverage classification performance. Specifically, multiple learning paths are introduced in the MxDRNN to extract discriminative features by permutating input dummy orders. Eight datasets from five different fields (MNIST, 3D-MNIST, CIFAR, VGGFace2, and lung screening computed tomography) are included to evaluate the performance of our method. The proposed MxDRNN improves the baseline performance by a large margin across the different application fields (e.g., accuracy from 46.40% to 76.54% in VGGFace2 test pose set, AUC from 0.7418 to 0.8162 in NLST lung dataset). Additionally, empirical experiments show the MxDRNN is more robust to category-irrelevant attributes (e.g., expression, pose in face images), which may introduce difficulties for image classification and algorithm generalizability. The code is publicly available.