25 research outputs found

    EFFECTIVE COMBINING OF COLOR AND TEXTURE DESCRIPTORS FOR INDOOR-OUTDOOR IMAGE CLASSIFICATION

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    Although many indoor-outdoor image classification methods have been proposed in the literature, most of them have omitted comparison with basic methods to justify the need for complex feature extraction and classification procedures. In this paper we propose a relatively simple but highly accurate method for indoor-outdoor image classification, based on combination of carefully engineered MPEG-7 color and texture descriptors. In order to determine the optimal combination of descriptors which is characterized by efficient extraction, compact representation and high accuracy, we conducted comprehensive empirical tests over several color and texture descriptors. The optimal descriptors combination was used for training and testing of a binary SVM classifier. We have shown that the proper descriptors preprocessing before SVM classification has significant impact on the final result. Comprehensive experimental evaluation shows that the proposed method outperforms several more complex indoor-outdoor image classification techniques on a couple of public datasets

    The Moore-Penrose inverse of a companion matrix

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    Necessary and sufficient conditions are given for the Moore-Penrose inverse of a companion matrix over an arbitrary ring to exist.This research was financed by FEDER Funds through ``Programa Operacional Factores de Competitividade - COMPETE'' and by Portuguese Funds through FCT - ``Fundação para a Ciência e a Tecnologia'', within the project PEst-C/MAT/UI0013/2011

    Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study

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    PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

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    PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    On the continuity of the group inverse in C*-Algebras

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    [EN] Let {a_n} be a sequence of group invertible elements of a unital C* algebra A that converges to a. We present some equivalent conditions for the group invertibility of a and for the convergence of {a^#_n} to a#.The first author was supported by the Universidad Politecnica de Valencia (PAID-06-12). The second author is supported by Grant No. 174007 of the Ministry of Science, Technology and Development, Republic of Serbia. The third author is supported by the Guangxi Natural Science Foundation 2013 GXNS-FAA019008, the key project of Education Department of Guangxi 201202ZD031 Project and by national science foundation of China 11361009.Benítez López, J.; Cvetkovic-Ilic, D.; Liu, X. (2014). On the continuity of the group inverse in C*-Algebras. Banach Journal of Mathematical Analysis. 8(2):204-213. https://doi.org/10.15352/bjma/1396640064S2042138

    Chemometric characterization of peach, nectarine and plum cultivars according to fruit phenolic content and antioxidant activity

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    Introduction. Deciduous tree fruits like peach (Prunus persica (L.) Batsch var. persica), nectarine (Prunus persica (L.) Batsch var. nucipersica (Suckow) C.K.Schneid), and especialy plum (Prunus domestica L. ssp. domestica) are very common in Serbia. These fruits are known for their nutritional value and therapeutic properties and are valuable sources of antioxidants. Materials and methods. The goal of this work was to evaluate fruit tissue antioxidant activity using methanol extracts of 9 peach, 3 nectarine and 7 plum cultivars. The following parameters were measured: total phenolic content (TPC); antioxidant activity as estimated by radical scavenging activity of (2,2-diphenyl-1-picrylhydrazyl, DPPH); cation decolorization activity (2,2-azinobis-3 ethylbenxothiazoline-6-sulphonic acid, ABTS); ferric reducing antioxidant power (FRAP); cupric reducing antioxidant capacity (CUPRAC); and total reducing power (TRP). Results and discussion. Total phenolic contents of the plum cultivars were higher than those of peach and nectarine and significant positive correlations were recorded between all antioxidant activity assays and total phenolic contents. Results obtained by principal component analysis (PCA) are in agreement with those obtained by cluster analysis (CA). Conclusion. The selected methods revealed antioxidant activities for all plum cultivars significantly higher than in the peach and nectarine cultivars. PCA and CA allow grouping the different fruit species based on TPC, DPPH, ABTS, TRP, FRAP and CUPRAC values

    IMPLANTATION OF AN ICD AND DFT TESTING IN PATIENT WITH PERSISTENT LEFT SUPERIOR VENA CAVA

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    Aim. The implantable cardioverter-defibrillator [ICD] has been proven to reduce the risk of sudden cardiac death through the termination of ventricular fibrillation and life-threatening ventricular tachycardia. The simplest measure of defibrillation effectiveness is the DFT, defined as the lowest delivered shock strength required to defibrillate. Improved technology and use of ICDs for primary prevention have led some to question the need for either defibrillation testing or any assessment of defibrillation efficacy after implantation. Experts disagree about optimal testing because data are insufficient to define the trade-off between accuracy and risk of testing. However there are specific cases in which DFT is necessary.Material and methods. Authors describe the case of a patient with persistent left vena cava, a rare congenital anomaly, with no clinical importance which is usually accidentally revealed during the implantation of pacemaker or when placing a central vascular catheter. However, it represents a major problem and challenge for positioning of the standard pacemaker electrodes.Results. After a successful implantation via unconventional anatomic path authors carried out DFT testing to check that the device is functioning appropriately.Conclusion. Persistent left vena cava should not represent a contraindication for implantation of complex pacemaker systems such as ICD and DFT testing is advisable in this cases
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