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61.
Universal impulse noise filter based on genetic programming. 总被引:1,自引:0,他引:1
In this paper, we present a novel method for impulse noise filter construction, based on the switching scheme with two cascaded detectors and two corresponding estimators. Genetic programming as a supervised learning algorithm is employed for building two detectors with complementary characteristics. The first detector identifies the majority of noisy pixels. The second detector searches for the remaining noise missed by the first detector, usually hidden in image details or with amplitudes close to its local neighborhood. Both detectors are based on the robust estimators of location and scale-median and MAD. The filter made by the proposed method is capable of effectively suppressing all kinds of impulse noise, in contrast to many existing filters which are specialized only for a particular noise model. In addition, we propose the usage of a new impulse noise model-the mixed impulse noise, which is more realistic and harder to treat than existing impulse noise models. The proposed model is the combination of commonly used noise models: salt-and-pepper and uniform impulse noise models. Simulation results show that the proposed two-stage GP filter produces excellent results and outperforms existing state-of-the-art filters. 相似文献
62.
Katharina B. Kuentzel Ivan Bradi Alena Akhmetshina Melanie Korbelius Silvia Rainer Dagmar Kolb Martin Gauster Nemanja Vuji Dagmar Kratky 《International journal of molecular sciences》2021,22(19)
Cholesterol and fatty acids are essential lipids that are critical for membrane biosynthesis and fetal organ development. Cholesteryl esters (CE) are degraded by hormone-sensitive lipase (HSL) in the cytosol and by lysosomal acid lipase (LAL) in the lysosome. Impaired LAL or HSL activity causes rare pathologies in humans, with HSL deficiency presenting less severe clinical manifestations. The infantile form of LAL deficiency, a lysosomal lipid storage disorder, leads to premature death. However, the importance of defective lysosomal CE degradation and its consequences during early life are incompletely understood. We therefore investigated how defective CE catabolism affects fetus and infant maturation using Lal and Hsl knockout (-/-) mouse models. This study demonstrates that defective lysosomal but not neutral lipolysis alters placental and fetal cholesterol homeostasis and exhibits an initial disease pathology already in utero as Lal-/- fetuses accumulate hepatic lysosomal lipids. Immediately after birth, LAL deficiency exacerbates with massive hepatic lysosomal lipid accumulation, which continues to worsen into young adulthood. Our data highlight the crucial role of LAL during early development, with the first weeks after birth being critical for aggravating LAL deficiency. 相似文献
63.
Begovic M.M. Djuric P.M. Dunlap S. Phadke A.G. 《Power Delivery, IEEE Transactions on》1993,8(2):480-486
Three new techniques for frequency measurement are proposed. The first is a modified zero-crossing method using curve fitting of voltage samples. The second method is based on polynomial fitting of the discrete Fourier transform (DFT) quasi-stationary phasor data for calculation of the rate of change of the positive sequence phase angle. The third method operates on a complex signal obtained by the standard technique of quadrature demodulation. All three methods are characterized by immunity to reasonable amounts of noise and harmonics in power systems. The performance of the proposed techniques is illustrated for several scenarios by computer simulation 相似文献
64.
Miljana Z. Jovandaric Milan Dokic Ivana R. Babovic Srboljub Milicevic Jelena Dotlic Branislav Milosevic Miljan Culjic Luka Andric Nemanja Dimic Olga Mitrovic Aleksandra Beleslin Jovana Nikolic Zorica Jestrovic Sandra Babic 《International journal of molecular sciences》2022,23(23)
Coronavirus disease (COVID-19) is an infectious disease caused by SARS-CoV-2. Elderly people, people with immunodeficiency, autoimmune and malignant diseases, as well as people with chronic diseases have a higher risk of developing more severe forms of the disease. Pregnant women and children can becomesick, although more often they are only the carriers of the virus. Recent studies have indicated that infants can also be infected by SARS-CoV-2 and develop a severe form of the disease with a fatal outcome. Acute Respiratory Distress Syndrome (ARDS) ina pregnant woman can affect the supply of oxygen to the fetus and initiate the mechanism of metabolic disorders of the fetus and newborn caused by asphyxia. The initial metabolic response of the newborn to the lack of oxygen in the tissues is the activation of anaerobic glycolysis in the tissues and an increase in the concentration of lactate and ketones. Lipid peroxidation, especially in nerve cells, is catalyzed by iron released from hemoglobin, transferrin and ferritin, whose release is induced by tissue acidosis and free oxygen radicals. Ferroptosis-inducing factors can directly or indirectly affect glutathione peroxidase through various pathways, resulting in a decrease in the antioxidant capacity and accumulation of lipid reactive oxygen species (ROS) in the cells, ultimately leading to oxidative cell stress, and finally, death. Conclusion: damage to the mitochondria as a result of lipid peroxidation caused by the COVID-19 disease can cause the death of a newborn and pregnant women as well as short time and long-time sequelae. 相似文献
65.
Ana Ilic Dusan Todorovic Slavica Mutavdzin Novica Boricic Biljana Bozic Nedeljkovic Sanja Stankovic Tatjana Simic Predrag Stevanovic Vera Celic Dragan Djuric 《International journal of molecular sciences》2021,22(6)
The possible cardioprotective effects of translocator protein (TSPO) modulation with its ligand 4′-Chlorodiazepam (4′-ClDzp) in isoprenaline (ISO)-induced rat myocardial infarction (MI) were evaluated, alone or in the presence of L-NAME. Wistar albino male rats (b.w. 200–250 g, age 6–8 weeks) were divided into 4 groups (10 per group, total number N = 40), and certain substances were applied: 1. ISO 85 mg/kg b.w. (twice), 2. ISO 85 mg/kg b.w. (twice) + L-NAME 50 mg/kg b.w., 3. ISO 85 mg/kg b.w. (twice) + 4′-ClDzp 0.5 mg/kg b.w., 4. ISO 85 mg/kg b.w. (twice) + 4′-ClDzp 0.5 mg/kg b.w. + L-NAME 50 mg/kg b.w. Blood and cardiac tissue were sampled for myocardial injury and other biochemical markers, cardiac oxidative stress, and for histopathological evaluation. The reduction of serum levels of high-sensitive cardiac troponin T hs cTnT and tumor necrosis factor alpha (TNF-α), then significantly decreased levels of serum homocysteine Hcy, urea, and creatinine, and decreased levels of myocardial injury enzymes activities superoxide dismutase (SOD) and glutathione peroxidase (GPx) as well as lower grades of cardiac ischemic changes were demonstrated in ISO-induced MI treated with 4′-ClDzp. It has been detected that co-treatment with 4′-ClDzp + L-NAME changed the number of registered parameters in comparison to 4′-ClDzp group, indicating that NO (nitric oxide) should be important in the effects of 4′-ClDzp. 相似文献
66.
Jovana N. Jeremic Vladimir Lj. Jakovljevic Vladimir I. Zivkovic Ivan M. Srejovic Jovana V. Bradic Isidora M. Milosavljevic Slobodanka Lj. Mitrovic Nemanja U. Jovicic Sergey B. Bolevich Andrey A. Svistunov Suresh C. Tyagi Nevena S. Jeremic 《International journal of molecular sciences》2020,21(23)
This study aimed to examine the effects of diallyl trisulfide (DATS), the most potent polysulfide derived from garlic, on metabolic syndrome and myocardial function in rats with metabolic syndrome (MetS). For that purpose, we used 36 male Wistar albino rats divided into control rats, rats with MetS and MetS rats treated with 40 mg/kg of DATS every second day for 3 weeks. In the first part, we studied the impact of DATS on MetS control and found that DATS significantly raised H2S, decreased homocysteine and glucose levels and enhanced lipid and antioxidative, while reducing prooxidative parameters. Additionally, this polysulfide improved cardiac function. In the second part, we investigated the impact of DATS on ex vivo induced ischemia/reperfusion (I/R) heart injury and found that DATS consumption significantly improved cardiodynamic parameters and prevented oxidative and histo-architectural variation in the heart. In addition, DATS significantly increased relative gene expression of eNOS, SOD-1 and -2, Bcl-2 and decreased relative gene expression of NF-κB, IL-17A, Bax, and caspases-3 and -9. Taken together, the data show that DATS can effectively mitigate MetS and have protective effects against ex vivo induced myocardial I/R injury in MetS rat. 相似文献
67.
Nuri Ayat Bezaatpour Abolfazl Amiri Mandana Vucetic Nemanja Mikkola Jyri-Pekka Murzin Dmitry Yu. 《Catalysis Letters》2022,152(4):991-1002
Catalysis Letters - Mesoporous SBA-15 silicate with a high surface area was prepared by a hydrothermal method, successively modified by organic melamine ligands and then used for deposition of Pd... 相似文献
68.
MgO Antibacterial Properties: Fewer Defects in the Surface Slows the Hydrolysis Rate,Decreases the ROS Generation Potential,and Improves the Non‐ROS Antimicrobial Activity of MgO (Small 26/2018)
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69.
Sandra Grbic Jelena Parojcic Zorica Djuric Svetlana Ibric 《Drug development and industrial pharmacy》2013,39(7):852-856
Aim: The equilibrium-based mathematical model was used to describe the pH-surfactant-mediated solubilization of weakly acidic electrolyte, nimesulide, in buffer solutions. This model assumed that the total drug solubility could be expressed as a sum of the solubilities of four different species: unionized and ionized form in solution and their corresponding micellar forms. Sucrose-laurate, new synthetic surfactant, and polysorbate 80 were investigated for their benefits in the testing of poorly soluble acidic model drug. Method: Two sets of solubility data, determined at pH values 4.5 and 9.0 in media containing different surfactant concentrations, were used to calculate solubilization slopes and corresponding micellar equilibrium constants for the unionized (Kn) and ionized (Ki) drug. These values were used to estimate drug solubilization in media considered to represent physiologically relevant conditions. Results: Predicted solubility values were in good agreement with the experimental data, suggesting that the impact of pH and surfactant on nimesulide solubility could be well characterized by the equilibrium model described in this article. Conclusions: Obtained results indicated that the extent of solubilization was significantly dependent on the surfactant used. 相似文献
70.
Mirjana Djuric jelka Mihajlov Ljiljana Petrasinovic-Stojkanovic Branislav Zivanovic 《Journal of the American Ceramic Society》1996,79(5):1252-1256
The paper offers a short review of investigations conducted on the Al2 O3 -SiO2 system, particularly from the point of view of an appearance of immiscibility gaps, below the liquidus temperatures. Based on theoretical criteria and using the data along the liquidus curves (for mullite and corundum), this investigation suggests immiscibility regions at both ends of the phase diagram. That is, it defines the Margules polynomials for calculation of the activity coefficients necessary for determining the Gibbs energy of mixing. Obtained results are in good agreement with the results reported by Risbud and Pask and other investigators who have found immiscibility gaps at rather high temperatures. 相似文献