In order to solve the problem of complexity of zero-crossing detection and distortion of input current waveform, a novel control method is proposed for interleaved Boost PFC converter operates in ...critical conduction mode. This method is based on a new switching voltage detection circuit. By detecting the drain-source voltage of MOS transistor, the zero crossing signal is obtained through the comparator, and switch achieves zero voltage switching or valley switching, which greatly reduces the switching loss. Adopting the switch conduction time compensatory strategy, it improves the average inductor current and distortion of input current waveform caused by resonance between inductance and parasitic capacitance of MOS transistor. Finally, an 800 W prototype is built and experimental results show the efficiency and feasibility of this method.
Introduction
The obesity epidemic is an important public health problem in the United States. Previous studies have revealed the association between obesity and various surgical complications. ...Tracheostomy which is an important lifesaving procedure may prove technically challenging in an obese patient. This study sought to evaluate the association between obesity and early complications following standard tracheostomy using a national registry.
Methods
Adult patients who underwent tracheostomy from 2007 to 2017 were analyzed using the Nationwide Inpatient Sample (NIS). The population was stratified into obese and non-obese groups. Early complications following standard tracheostomy were identified and compared between the two groups. Multivariable logistic regression analyses were performed to assess the association between obesity and early complications following tracheostomy.
Results
Data pertaining to 205 032 adult patients were evaluated. Obese patients accounted for 12.1% (n = 21 816) of the entire cohort. The most common complication in the cohort was perioperative bleeding (4316 2.1%). A total of 1382 (0.67%), 949 (0.46%), and 134 (0.07%) patients developed pneumothorax/pneumomediastinum, stoma/surgical site infection, and tracheal injury following standard tracheostomy, respectively. There was no difference in the odds of tracheal injury, perioperative bleeding, and pneumomediastinum/pneumothorax following standard tracheostomy in the obese and non-obese group in multivariable analysis. However, obesity was associated with 60% increased odds of developing stoma/surgical site infection following standard tracheostomy (OR 1.60 1.33-1.92, P < 0.01).
Conclusion
Obesity is associated with an increased risk of developing stoma/surgical site infection following standard tracheostomy. This adds to the growing need for measures to help curb the obesity epidemic in a bid to improve surgical outcomes.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
Process mining can provide greater insight into medical treatment processes and organizational processes in healthcare. To enhance comparability between processes, the quality of the labelled-data is ...essential. A literature review of the clinical case studies by Rojas et al. in 2016 identified several common aspects for comparison, which include methodologies, algorithms or techniques, medical fields, and healthcare specialty. However, clinical aspects are not reported in a uniform way and do not follow a standard clinical coding scheme. Further, technical aspects such as details of the event log data are not always described. In this paper, we identified 38 clinically-relevant case studies of process mining in healthcare published from 2016 to 2018 that described the tools, algorithms and techniques utilized, and details on the event log data. We then correlated the clinical aspects of patient encounter environment, clinical specialty and medical diagnoses using the standard clinical coding schemes SNOMED CT and ICD-10. The potential outcomes of adopting a standard approach for describing event log data and classifying medical terminology using standard clinical coding schemes are further discussed. A checklist template for the reporting of case studies is provided in the Appendix A to the article.
Proper growth of dendrites is critical to the formation of neuronal circuits, but the cellular machinery that directs the addition of membrane components to generate dendritic architecture remains ...obscure. Here, we demonstrate that post-Golgi membrane trafficking is polarized toward longer dendrites of hippocampal pyramidal neurons in vitro and toward apical dendrites in vivo. Small Golgi outposts partition selectively into longer dendrites and are excluded from axons. In dendrites, Golgi outposts concentrate at branchpoints where they engage in post-Golgi trafficking. Within the cell body, the Golgi apparatus orients toward the longest dendrite, and this Golgi polarity precedes asymmetric dendrite growth. Manipulations that selectively block post-Golgi trafficking halt dendrite growth in developing neurons and cause a shrinkage of dendrites in mature pyramidal neurons. Further, disruption of Golgi polarity produces neurons with symmetric dendritic arbors lacking a single longest principal dendrite. These results define a novel polarized organization of neuronal secretory trafficking and demonstrate a mechanistic link between directed membrane trafficking and asymmetric dendrite growth.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Purpose
To assess the repeatability and reliability of semi-automated EyeMark Python program measurements compared to manual ImageJ image processing of anterior segment-optical coherence tomography ...(AS-OCT) structures in healthy and keratoconus eyes.
Methods
Heidelberg AS-OCT was used to image 25 eyes from 14 healthy subjects and 25 eyes from 15 subjects with keratoconus between the ages of 20 and 80 years, collected prospectively, in this observational case–control study. Visual axis scan containing vertical fixation light beam was selected from the 15-line AS-OCT scan raster. Central corneal thickness (CCT), anterior corneal radius of curvature (ACRC), posterior corneal radius of curvature (PCRC), and truncated anterior vault (TAV) were measured using ImageJ software and the EyeMark Python program. MedCalc and R were used to calculate the intraclass correlation coefficient (ICC) and generate Bland–Altman plots (BAP).
Results
When comparing the measurements of CCT, ACRC, PCRC, and TAV between manual ImageJ analysis and the EyeMark Python program, ICC values were consistently greater than 0.9, indicating excellent agreement. BAPs comparing the ImageJ and Python measurements of anterior segment structures show no systematic proportional bias and the average differences were near zero and within 95% of the limits of agreement.
Conclusions
Semi-automated tools may provide the necessary efficiency for point-of-care quantitative corneal analysis of raw AS-OCT images. The semi-automated EyeMark Python program offers a repeatable and reliable tool compared to manual ImageJ analysis for measuring anterior segment structures from AS-OCT images among individuals with keratoconus.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
: Lipid metabolism plays an important role in maternal health and fetal development. There is a gap in the knowledge of how lipid metabolism changes during pregnancy for Black women who are at a ...higher risk of adverse outcomes. We hypothesized that the comprehensive lipidome profiles would show variation across pregnancy indicative of requirements during gestation and fetal development.
: Black women were recruited at prenatal clinics. Plasma samples were collected at 8-18 weeks (T
), 22-29 weeks (T
), and 30-36 weeks (T
) of pregnancy. Samples from 64 women who had term births (≥37 weeks gestation) were subjected to "shotgun" Orbitrap mass spectrometry. Mixed-effects models were used to quantify systematic changes and dimensionality reduction models were used to visualize patterns and identify reliable lipid signatures.
: Total lipids and major lipid classes showed significant increases with the progression of pregnancy. Phospholipids and glycerolipids exhibited a gradual increase from T
to T
to T
, while sphingolipids and total sterol lipids displayed a more pronounced increase from T
to T
. Acylcarnitines, hydroxy acylcarnitines, and Lyso phospholipid levels significantly decreased from T
to T
. A deviation was that non-esterified fatty acids decreased from T
to T
and increased again from T
to T
, suggestive of a potential role for these lipids during the later stages of pregnancy. The fatty acids showing this trend included key fatty acids-non-esterified Linoleic acid, Arachidonic acid, Alpha-linolenic acid, Eicosapentaenoic acid, Docosapentaenoic acid, and Docosahexaenoic acid.
: Mapping lipid patterns and identifying lipid signatures would help develop intervention strategies to reduce perinatal health disparities among pregnant Black women.
Several recent studies suggest that C24-C38 very long chain fatty acids (VLCFA) play an important role in vision, and decreased levels of retina VLCFA have been associated with vision disorders ...including the onset and progression of diabetic retinopathy in animal models. Traditional methods for VLCFA analysis lack the sensitivity and specificity needed to enable detailed characterization of VLCFA incorporation into complex lipids in tissues and subcellular components. To assess whether decreased VLCFA in diabetic retina are directly implicated in diabetes-induced breakdown of the blood-retinal barrier, we demonstrated the utility of performing untargeted lipid analysis via Orbitrap high resolution/accurate mass MS and MS/MS-based shotgun lipidomics to identify structural lipids containing VLCFA substituents. This comprehensive and highly sensitive approach to untargeted lipid identification enabled us to characterize low-abundance sphingolipids containing very long chain fatty acids from isolated retinal tight junction complexes, as well as VLCFA-containing phospholipids in retinal tissues. To facilitate future biochemical and physiological studies of the roles of VLCFA in blood-retina barrier integrity and maintenance of vision, this chapter describes steps to isolate tight junction complexes from a cell culture model of the outer blood-retinal barrier and perform untargeted Orbitrap high resolution/accurate mass-based lipid analysis to identify VLCFA in tight junctions and retina tissue.
Objectives: Creativity requires the ability to combine existing mental representations in new ways and depends, in part, on the hippocampus. Hippocampal function is, in turn, affected by a number of ...health factors, including aerobic fitness, excess adiposity, and diet. Specifically, in rodent studies, diets high in saturated fatty acids and sugar - hallmarks of a western diet- have been shown to negatively impact hippocampal function and thereby impair performance on cognitive tasks that require the hippocampus. Yet relatively few studies have examined the relationship between diet and hippocampal-dependent cognition in children.
Methods: The current study therefore sought to explore the relationship of several diet quality markers including dietary lipids (saturated fatty acids and omega-3 fatty acids), simple carbohydrates (added sugars), and dietary fiber with creativity in preadolescent children. Participants (N = 57; mean age = 9.1 years) completed the Verbal Form of the Torrance Test of Creative Thinking (TTCT), a standardized test of creativity known to require the hippocampus. Additionally, participants completed a 3-day food intake record with the assistance of a parent, underwent dual energy x-ray absorptiometry (DXA) to assess central adiposity, and VO
2
max testing to assess aerobic fitness.
Results: Added sugar intake was negatively associated, and dietary fiber was positively associated with overall TTCT performance. These relationships were sustained even after controlling for key covariates.
Discussion: These findings are among the first to report an association between added sugar consumption and hippocampal-dependent cognition during childhood and, given the key role of the hippocampus in learning and memory, as well as creative thinking, have potential educational and public health implications.
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DOBA, FSPLJ, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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