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221.
H :[0, 1]×
3→
3, where H(t, r) for t=0 and t=1 are two given planar curves C
1(r) and C
2(r). The first t parameter defines the time of fixing the intermediate metamorphosis curve. The locus of H(t, r) coincides with the ruled surface between C
1(r) and C
2(r), but each isoparametric curve of H(t, r) is self-intersection free. The second algorithm suits morphing operations of planar curves. First, it constructs the best
correspondence of the relative parameterizations of the initial and final curves. Then it eliminates the remaining self-intersections
and flips back the domains that self-intersect. 相似文献
222.
Emanuele Stomeo Tatiana Kalganova Cyrille Lambert 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2006,36(5):1024-1043
Evolvable hardware (EHW) refers to self-reconfiguration hardware design, where the configuration is under the control of an evolutionary algorithm (EA). One of the main difficulties in using EHW to solve real-world problems is scalability, which limits the size of the circuit that may be evolved. This paper outlines a new type of decomposition strategy for EHW, the "generalized disjunction decomposition" (GDD), which allows the evolution of large circuits. The proposed method has been extensively tested, not only with multipliers and parity bit problems traditionally used in the EHW community, but also with logic circuits taken from the Microelectronics Center of North Carolina (MCNC) benchmark library and randomly generated circuits. In order to achieve statistically relevant results, each analyzed logic circuit has been evolved 100 times, and the average of these results is presented and compared with other EHW techniques. This approach is necessary because of the probabilistic nature of EA; the same logic circuit may not be solved in the same way if tested several times. The proposed method has been examined in an extrinsic EHW system using the (1 + lambda) evolution strategy. The results obtained demonstrate that GDD significantly improves the evolution of logic circuits in terms of the number of generations, reduces computational time as it is able to reduce the required time for a single iteration of the EA, and enables the evolution of larger circuits never before evolved. In addition to the proposed method, a short overview of EHW systems together with the most recent applications in electrical circuit design is provided. 相似文献
223.
Underground coal gasification (UCG) is one of the clean technologies to collect heat energy and gases (hydrogen, methane, etc.) in an underground coal seam. It is necessary to further developing environmentally friendly UCG system construction. One of the most important UCG’s problems is underground control of combustion area for efficient gas production, estimation of subsidence and gas leakage to the surface. For this objective, laboratory experiments were conducted according to the UCG model to identify the process of combustion cavity development by monitoring the electrical resistivity activity on the coal samples to setup fundamental data for the technology engineering to evaluate combustion area. While burning coal specimens, that had been sampled from various coal deposits, electrical resistivity was monitored. Symmetric four electrodes system (ABMN) of direct and low-frequency current electric resistance method was used for laboratory resistivity measurement of rock samples. Made research and the results suggest that front-end of electro conductivity activity during heating and combusting of coal specimen depended on heating temperature. Combusting coal electro conductivity has complicated multistage type of change. Electrical resistivity method is expected to be a useful geophysical tool to for evaluation of combustion volume and its migration in the coal seam. 相似文献
224.
Enzo Baccarelli Author VitaeNicola CordeschiAuthor Vitae Tatiana Patriarca Author Vitae 《Computer Networks》2012,56(1):287-302
In this work, the Stochastic Traffic Engineering (STE) problem arising from the support of QoS-demanding real-time (e.g., delay and delay-jitter sensitive) media-streaming applications over unreliable IP-over-wireless pipes is addressed. Two main contributions are presented. First, we develop an optimal resource-management policy that allows a joint scheduling of the source rate, transmit energy and playout rate. Salient features of the proposed scheduling policy are that: (i) it is self-adaptive; and, (ii) it is able to provide hard (i.e., deterministic) QoS guarantees, in terms of hard limited playout delay, playout rate-jitter and pre-roll delay. Second, by referring to power and bandwidth limited access scenarios, we develop a traffic analysis of the underlying IP-over-wireless pipes that allows us to analyze the effects of both fading-induced errors and congestion-induced packet’s losses on the end-to-end performance of the proposed scheduler. 相似文献
225.
Cleonardo Augusto Silva Arthur Ribeiro-dos-Santos Wanderson Gonalves Gonalves Pablo Pinto Rafael Pompeu Pantoja Tatiana Vinasco-Sandoval Andr Maurício Ribeiro-dos-Santos Mara Helena Hutz Amanda Ferreira Vidal Gilderlanio Santana Araújo ndrea Ribeiro-dos-Santos Sidney Santos 《International journal of molecular sciences》2021,22(7)
Simple SummaryTuberculosis is the leading cause of mortality from a single infectious agent and is among the top 10 causes of death worldwide. Despite that, few studies focus on regulatory elements such as small non-coding RNAs in tuberculosis. This pilot work applied Next Generation Sequencing techniques to evaluate the global miRNA expression profile of patients with active tuberculosis; their respective healthy physicians, who are at constant risk of infection; and a second group of healthy controls. In addition, we observed miRNA–gene interactions affected by exposure to the bacteria. Our findings indicate a list of miRNAs that could be used as potential biomarkers to improve treatment strategies at early stages. We also observed modified pathways related to the immune response due to differential miRNA expression profiles. Finally, we alert and encourage the development of new strategies to avoid long-term exposure of healthy physicians, considering how closely related their miRNA profile was to tuberculosis patients using current safety protocols.AbstractThe role of regulatory elements such as small ncRNAs and their mechanisms are poorly understood in infectious diseases. Tuberculosis is one of the oldest infectious diseases of humans and it is still a challenge to prevent and treat. Control of the infection, as well as its diagnosis, are still complex and current treatments used are linked to several side effects. This study aimed to identify possible biomarkers for tuberculosis by applying NGS techniques to obtain global miRNA expression profiles from 22 blood samples of infected patients with tuberculosis (n = 9), their respective healthy physicians (n = 6) and external healthy individuals as controls (n = 7). Samples were run through a pipeline consisting of differential expression, target genes, gene set enrichment and miRNA–gene network analyses. We observed 153 altered miRNAs, among which only three DEmiRNAs (hsa-let-7g-5p, hsa-miR-486-3p and hsa-miR-4732-5p) were found between the investigated patients and their respective physicians. These DEmiRNAs are suggested to play an important role in granuloma regulation and their immune physiopathology. Our results indicate that miRNAs may be involved in immune modulation by regulating gene expression in cells of the immune system. Our findings encourage the application of miRNAs as potential biomarkers for tuberculosis. 相似文献
226.
Yulia V. Vakhitova Tatiana S. Kalinina Liana F. Zainullina Anastasiya Yu. Lusta Anna V. Volkova Nikita V. Kudryashov Tatiana A. Gudasheva Alexander A. Shimshirt Ilya A. Kadnikov Mikhail V. Voronin Sergei B. Seredenin 《International journal of molecular sciences》2021,22(24)
Induction of BDNF-TrkB signaling is associated with the action mechanisms of conventional and fast-acting antidepressants. GSB-106, developed as a small dimeric dipeptide mimetic of BDNF, was previously shown to produce antidepressant-like effects in the mouse Porsolt test, tail suspension test, Nomura water wheel test, in the chronic social defeat stress model and in the inflammation-induced model of depression. In the present study, we evaluated the effect of chronic per os administration of GSB-106 to Balb/c mice under unpredictable chronic mild stress (UCMS). It was observed for the first time that long term GSB-106 treatment (1 mg/kg, 26 days) during ongoing UCMS procedure ameliorated the depressive-like behaviors in mice as indicated by the Porsolt test. In addition, chronic per os administration of GSB-106 resulted in an increase in BDNF levels, which were found to be decreased in the prefrontal cortex and hippocampus of mice after UCMS. Furthermore, prolonged GSB-106 treatment was accompanied by an increase in the content of pTrkB706/707 in the prefrontal cortex and by a pronounced increase in the level of pTrkB816 in both studied brain structures of mice subjected to UCMS procedure. In summary, the present data show that chronic GSB-106 treatment produces an antidepressant-like effect in the unpredictable chronic mild stress model, which is likely to be associated with the regulation of the BDNF-TrkB signaling. 相似文献
227.
Michele Dei Cas Tatiana Carrozzini Giuliana Pollaci Antonella Potenza Sara Nava Isabella Canavero Francesca Tinelli Gemma Gorla Ignazio G. Vetrano Francesco Acerbi Paolo Ferroli Elisa F. Ciceri Silvia Esposito Veronica Saletti Emilio Ciusani Aida Zulueta Rita Paroni Eugenio A. Parati Riccardo Ghidoni Anna Bersano Laura Gatti 《International journal of molecular sciences》2021,22(24)
Moyamoya arteriopathy (MA) is a rare cerebrovascular disorder characterized by ischemic/hemorrhagic strokes. The pathophysiology is unknown. A deregulation of vasculogenic/angiogenic/inflammatory pathways has been hypothesized as a possible pathophysiological mechanism. Since lipids are implicated in modulating neo-vascularization/angiogenesis and inflammation, their deregulation is potentially involved in MA. Our aim is to evaluate angiogenic/vasculogenic/inflammatory proteins and lipid profile in plasma of MA patients and control subjects (healthy donors HD or subjects with atherosclerotic cerebrovascular disease ACVD). Angiogenic and inflammatory protein levels were measured by ELISA and a complete lipidomic analysis was performed on plasma by mass spectrometry. ELISA showed a significant decrease for MMP-9 released in plasma of MA. The untargeted lipidomic analysis showed a cumulative depletion of lipid asset in plasma of MA as compared to HD. Specifically, a decrease in membrane complex glycosphingolipids peripherally circulating in MA plasma with respect to HD was observed, likely suggestive of cerebral cellular recruitment. The quantitative targeted approach demonstrated an increase in free sphingoid bases, likely associated with a deregulated angiogenesis. Our findings indicate that lipid signature could play a central role in MA and that a detailed biomarker profile may contribute to untangle the complex, and still obscure, pathogenesis of MA. 相似文献
228.
Kalpana Tilekar Neha Upadhyay Prof. Franz-Josef Meyer-Almes Dr. Fulvio Loiodice Natalia Y. Anisimova Tatiana S. Spirina Darina V. Sokolova Galina B. Smirnova Dr. Jun-yong Choe Dr. Vadim S. Pokrovsky Prof. Antonio Lavecchia Prof. C S Ramaa 《ChemMedChem》2020,15(19):1813-1825
In search of novel and effective antitumor agents, pyrazoline-substituted pyrrolidine-2,5-dione hybrids were designed, synthesized and evaluated in silico, in vitro and in vivo for anticancer efficacy. All the compounds exhibited remarkable cytotoxic effects in MCF7 and HT29 cells. The excellent antiproliferative activity toward MCF7 (IC50=0.78±0.01 μM), HT29 (IC50=0.92±0.15 μM) and K562 (IC50=47.25±1.24 μM) cell lines, prompted us to further investigate the antitumor effects of the best compound S2 (1-(2-(3-(4-fluorophenyl)-5-(p-tolyl)-4,5-dihydro-1H-pyrazol-1-yl)-2-oxoethyl)pyrrolidine-2,5-dione). In cell-cycle analysis, S2 was found to disrupt the growth phases with increased cell population in G1/G0 phase and decreased cell population in G2/M phase. The excellent in vitro effects were also supported by inhibition of anti-apoptotic protein Bcl-2. In vivo tumor regression studies of S2 in HT29 xenograft nude mice, exhibited equivalent and promising tumor regression with maximum TGI, 66 % (i. p. route) and 60 % (oral route) at 50 mg kg−1 dose by both the routes, indicating oral bioavailability and antitumor efficacy. These findings advocate that hybridization of pyrazoline and pyrrolidine-2,5-dioes holds promise for the development of more potent and less toxic anticancer agents. 相似文献
229.
Ignazio G. Vetrano Michele Dei Cas Vittoria Nazzi Marica Eoli Niccol Innocenti Veronica Saletti Antonella Potenza Tatiana Carrozzini Giuliana Pollaci Gemma Gorla Rita Paroni Riccardo Ghidoni Laura Gatti 《International journal of molecular sciences》2022,23(1)
Peripheral nerve sheath tumors (PNSTs) include schwannomas, neurofibromas (NFs), and plexiform neurofibromas (PNFs), among others. While they are benign tumors, according to their biological behavior, some have the potential for malignant degeneration, mainly PNFs. The specific factors contributing to the more aggressive behavior of some PNSTs compared to others are not precisely known. Considering that lipid homeostasis plays a crucial role in fibrotic/inflammatory processes and in several cancers, we hypothesized that the lipid asset was also unbalanced in this group of nerve tumors. Through untargeted lipidomics, NFs presented a significant increase in ceramide, phosphatidylcholine, and Vitamin A ester. PNFs displayed a marked decrease in 34 out of 50 lipid class analyzed. An increased level of ether- and oxidized-triacylglycerols was observed; phosphatidylcholines were reduced. After sphingolipidomic analysis, we observed six sphingolipid classes. Ceramide and dihydroceramides were statistically increased in NFs. All the glycosylated species appeared reduced in NFs, but increased in PNFs. Our findings suggested that different subtypes of PNSTs presented a specific modulation in the lipidic profile. The untargeted and targeted lipidomic approaches, which were not applied until now, contribute to better clarifying bioactive lipid roles in PNS natural history to highlight disease molecular features and pathogenesis. 相似文献
230.
Jefferson Rodrigues de Souza Lilian da Silva Márcia Silva da Rocha Tatiana Dillenburg Saint’Pierre 《Food Analytical Methods》2017,10(9):3088-3097
The aim of this work was to evaluate different approaches employing a reaction cell to circumvent spectral interferences over 80Se+ to increase the sensitivity in the determination of Se by inductively coupled plasma mass spectrometry (ICP-MS). Different gases (NH3, CH4, and O2) were employed, and the operating conditions were optimized by a central composite design, evaluating the effect of the reaction gas flow rate and the rejection parameter q (Rpq) on the limit of detection (LOD) of the method. All reaction gases studied reduced the interference by 40Ar2 + over 80Se+, reducing the LOD when compared to the LOD obtained with ICP-MS operating in the standard mode (LOD = 0.2 μg kg?1). A better LOD (0.01 μg kg?1) was obtained with CH4, while 0.1 μg kg?1 was the LOD with NH3. The use of O2 as a reaction gas enabled the determination of Se at m/z 96 (80Se16O+) with adequate analytical performance (LOD = 0.03 μg kg?1). The accuracy of the method was evaluated by analyzing the certified reference material (CRM) Selm-1, and the results obtained ranged from 99 to 104% of the certified value. In addition, Se dietary supplements of four different brands and commercial yeast were analyzed, and the major sources of uncertainty were studied. The dietary supplements followed the criteria adopted by Brazilian legislation, although the uncertainty study highlighted the great variation in the Se content of each brand. Clearly, the manufacturing process of dietary supplements needs more rigorous quality control, considering that this product can affect the health of consumers. 相似文献