25 research outputs found

    Circular Average Filtering and Circular Linear Interpolation in Complex Color Spaces

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    In color spaces where the chromatic term is given in polar coordinates, the shortest distance between colors of the same value is circular. By converting such a space into a complex polar form with a real-valued value axis, a color algebra for combining colors is immediately available. In this work, we introduce two complex space operations utilizing this observation: circular average filtering and circular linear interpolation. These operations produce Archimedean Spirals, thus guaranteeing that they operate along the shortest paths. We demonstrate that these operations provide an intuitive way to work in certain color spaces and that they are particularly useful for obtaining better filtering and interpolation results. We present a set of examples based on the perceptually uniform color space CIELAB or L*a*b* with its polar form CIEHLC. We conclude that representing colors in a complex space with circular operations can provide better visual results by exploitation of the strong algebraic properties of complex space C.Comment: 10 page

    Curved Space-Filling Tiles Using Voronoi Decomposition with Line, and Curve Segments Closed Under Wallpaper Symmetries

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    In this paper, we present a new approach to obtain symmetric tiles with curved edges. Our approach is based on using higher-order Voronoi sites that are closed under wallpaper symmetries. The resulting Voronoi tessellations provide us with symmetric tiles with curved edges. We have developed a web application that provides real-time tile design. Our application can be found at https://voronoi.viz.tamu.edu. One of our key findings in this paper is that not all symmetry operations are useful for creating curved tiles. In particular, all symmetries that use mirror operation produce straight lines that are useless for creating new tiles. This result is interesting because it suggests that we need to avoid mirror transformations to produce unusual space-filling tiles in 2D and 3D using Voronoi tessellations.Comment: 1

    Comparison of Fatigue Levels, Muscle Strength, Balance, and Exercise Performance of Young Adults with a History of Mild COVID-19 and Healthy Adults

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    Aim: The coronavirus disease-2019 (COVID-19) infection directly impacts fatigue and exercise performance. More studies have focused on these problems and were conducted with hospitalized patients and/or adult and geriatric populations. The aim of this study was to explore the effects of mild COVID-19 on fatigue, muscle strength, balance, and exercise performance, specifically in young adults. Methods: This research was designed as a case-control study, and tests were conducted between January 2022 and June 2022. The study included 60 participants aged 18-28, consisting of individuals who had a mild COVID-19 diagnosis within the past year (study group, n=30) and tested negative during the study, as well as a control group of individuals who had no COVID-19 diagnosis or symptoms within the past year (control group, n=30). The participants’ fatigue levels (Chalder Fatigue Scale), lower (Biodex Isokinetic-Dynamometer) and upper (Jamar-Handgrip Dynamometer) extremity muscle strength, balance (Y-Balance Test), and exercise performance (Queen’s College Step Test) were evaluated using various standardized tests. Results: Measurements showed that individuals with COVID-19 had an increase in fatigue scores (p=0.02). It was determined that fatigue was particularly prominent in women. Due to this difference that arose according to gender, it was observed that fatigue scores in those who had experienced COVID-19 were negatively correlated with muscle strength measurements. Conclusion: This study showed that symptoms of fatigue persisted in younger individuals, especially women, even after the COVID-19 infection. We think the next research should focus on COVID-19 symptoms, surveillance, and therapy in different age groups

    Strength of selection pressure is an important parameter contributing to the complexity of antibiotic resistance evolution

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    Revealing the genetic changes responsible for antibiotic resistance can be critical for developing novel antibiotic therapies. However, systematic studies correlating genotype to phenotype in the context of antibiotic resistance have been missing. In order to fill in this gap, we evolved 88 isogenic Escherichia coli populations against 22 antibiotics for 3 weeks. For every drug, two populations were evolved under strong selection and two populations were evolved under mild selection. By quantifying evolved populations' resistances against all 22 drugs, we constructed two separate cross-resistance networks for strongly and mildly selected populations. Subsequently, we sequenced representative colonies isolated from evolved populations for revealing the genetic basis for novel phenotypes. Bacterial populations that evolved resistance against antibiotics under strong selection acquired high levels of cross-resistance against several antibiotics, whereas other bacterial populations evolved under milder selection acquired relatively weaker cross-resistance. In addition, we found that strongly selected strains against aminoglycosides became more susceptible to five other drug classes compared with their wild-type ancestor as a result of a point mutation on TrkH, an ion transporter protein. Our findings suggest that selection strength is an important parameter contributing to the complexity of antibiotic resistance problem and use of high doses of antibiotics to clear infections has the potential to promote increase of cross-resistance in clinics

    Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

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    Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

    The effects of therapeutic intermittent hypoxia implementation on complete blood count parameters: an experimental animal model

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    Objective: Intermittent hypoxia (IH) implementation is a method performed by intermittently decreasing oxygen concentration in inhaled air at specific rate. This method varies between studies in terms of its application. This study aims to examine the changes in Complete Blood Count (CBC) parameters caused by IH implementation at therapeutic dose ranges with a single model. Methods: Ten Sprague Dawley type adult male rats were divided into two groups. In the study group, FiO2 level of inhaled air, was reduced to 10% in hypoxic cycle. 5 minutes normoxia-hypoxia cycle was used in each 30 minutes experiment period for study group. Control group remained in normoxic air for 30 minutes. 1 cc of blood was taken from mandibular vein from all rats at the end of 6th day. CBC analyzes were performed and differences between two groups were investigated. Results: Significant differences were detected in some CBC parameters between the two groups. It was determined that significant increase in MONO (p<0.001), MONO% (p<0.001), MCH (p=0.03), PLT (p=0.013) and PCT (p=0.007) parameters and significant decrease in MPV (p=0.02) parameters, in favor of study group. Conclusion: IH implementation was caused significant changes in MONO, MONO%, MCH, PCT, PLT and MPV parameters in the CBC analysis of rats. Considering the study results, therapeutic IH implementation may thought to have important effects in terms of lung protection and regeneration. Further research may focus on this point for precising and supporting of this study’ results
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