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In this paper, the influence of the selected sound features on distinguishing between musical instruments is presented. The features were chosen basing on our previous research. Coherent groups of features were created on the basis of significant features, according to the parameterization method applied, in order to constitute small, homogenous groups. In this research, we investigate (for each feature group separately) if there exist significant differences between means of these features for the studied instruments. We apply analysis of variance along with post hoc comparisons in the form of homogeneous groups, defined by mean values of the investigated features for our instruments. If a statistically significant difference is found, then the homogenous group is established. Such a group may consist of only one instrument (distinguished by this feature), or more (instruments similar with respect to this feature). The results show which instruments can be best discerned by which features.  相似文献   
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This paper presents a new supervised method for segmentation of blood vessels in retinal photographs. This method uses an ensemble system of bagged and boosted decision trees and utilizes a feature vector based on the orientation analysis of gradient vector field, morphological transformation, line strength measures, and Gabor filter responses. The feature vector encodes information to handle the healthy as well as the pathological retinal image. The method is evaluated on the publicly available DRIVE and STARE databases, frequently used for this purpose and also on a new public retinal vessel reference dataset CHASE_DB1?which is a subset of retinal images of multiethnic children from the Child Heart and Health Study in England (CHASE) dataset. The performance of the ensemble system is evaluated in detail and the incurred accuracy, speed, robustness, and simplicity make the algorithm a suitable tool for automated retinal image analysis.  相似文献   
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The Pechinni method (A) as well as hydrothermal treatment (B) of co-precipitated CeO2-based gels with NaOH solution were used to synthesise pure CeO2, and CeO2-based solid solutions with formula Ce1−xMxO2, Ce1−x(M0.5Ca0.5)xO2 M = Gd, Sm for 0.15 < x < 0.3 nanopowders. The thermal evolution of CeO2-based precursors during heating them up to 1000 °C was monitored by thermal (TG, DTA) analysis and X-ray diffraction method. All nanopowders and samples sintered were found to be pure CeO2 or ceria-based solutions with fluorite-type structure. The microstructure of CeO2-based sintered samples at 1500 °C (A) or 1250 °C (B) was observed for 2 h under the scanning electron microscope. The electrical properties of singly Ce1−xMxO2 or doubly doped CeO2-based samples with formula Ce1−x(M0.5Ca0.5)xO2, M = Gd, Sm, 0.15 < x < 0.30 were investigated by means of the ac impedance spectroscopy method throughout the temperature range of 600-800 °C. It has been stated that partial substitution of calcium by samarium or calcium by gadolinium in the Ce1−x(M0.5Ca0.5)xO2, M = Gd, Sm solid solutions leads to ionic conductivity enhancement comparable with only samaria- or gadolina-doped ceria. The CeO2-based samples with small-grained microstructures obtained from powders synthesised by hydrothermal method exhibited better ionic conductivity than samples with the same composition obtained from powders synthesised by the Pechinii method. The stability of the electrolytic properties of selected co-doped ceria sinters in fuel gases (H2, CH4) as well as exhaust gases from diesel engine was also investigated. The co-doped Ce0.8(Sm0.5Ca0.5)0.2O2 or Ce0.85(Gd0.5Ca0.5)0.15O2 dense samples would appear be to more adequate oxide electrolytes than Ce1−xMxO2, M = Sm, Gd and x = 0.15 or 0.2 for electrochemical devices operating at temperatures ranging from 600 to 700 °C.  相似文献   
107.
Dr. Nicolas Boutard  Dr. Arkadiusz Białas  Dr. Aleksandra Sabiniarz  Paweł Guzik  Dr. Katarzyna Banaszak  Dr. Artur Biela  Marcin Bień  Anna Buda  Barbara Bugaj  Dr. Ewelina Cieluch  Dr. Anna Cierpich  Dr. Łukasz Dudek  Dr. Hans-Michael Eggenweiler  Dr. Joanna Fogt  Dr. Monika Gaik  Dr. Andrzej Gondela  Krzysztof Jakubiec  Dr. Mirek Jurzak  Agata Kitlińska  Dr. Piotr Kowalczyk  Maciej Kujawa  Katarzyna Kwiecińska  Marcin Leś  Dr. Ralph Lindemann  Monika Maciuszek  Maciej Mikulski  Paulina Niedziejko  Alicja Obara  Henryk Pawlik  Tomasz Rzymski  Magdalena Sieprawska-Lupa  Dr. Marta Sowińska  Joanna Szeremeta-Spisak  Agata Stachowicz  Mateusz M. Tomczyk  Dr. Katarzyna Wiklik  Łukasz Włoszczak  Sylwia Ziemiańska  Dr. Adrian Zarębski  Dr. Krzysztof Brzózka  Dr. Mateusz Nowak  Dr. Charles-Henry Fabritius 《ChemMedChem》2019,14(1):169-181
Energy and biomass production in cancer cells are largely supported by aerobic glycolysis in what is called the Warburg effect. The process is regulated by key enzymes, among which phosphofructokinase PFK-2 plays a significant role by producing fructose-2,6-biphosphate; the most potent activator of the glycolysis rate-limiting step performed by phosphofructokinase PFK-1. Herein, the synthesis, biological evaluation and structure–activity relationship of novel inhibitors of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), which is the ubiquitous and hypoxia-induced isoform of PFK-2, are reported. X-ray crystallography and docking were instrumental in the design and optimisation of a series of N-aryl 6-aminoquinoxalines. The most potent representative, N-(4-methanesulfonylpyridin-3-yl)-8-(3-methyl-1-benzothiophen-5-yl)quinoxalin-6-amine, displayed an IC50 of 14 nm for the target and an IC50 of 0.49 μm for fructose-2,6-biphosphate production in human colon carcinoma HCT116 cells. This work provides a new entry in the field of PFKFB3 inhibitors with potential for development in oncology.  相似文献   
108.
Cancer is a heterogeneous disease, and even tumors with similar clinicopathological characteristics show different biology, behavior, and treatment responses. As a result, there is an urgent need to define new prognostic and predictive markers to make treatment options more personalized. According to the latest findings, nucleobindin-2/nesfatin-1 (NUCB2/NESF-1) is an important factor in cancer development and progression. Nucleobindin-2 is a precursor protein of nesfatin-1. As NUCB2 and nesfatin-1 are colocalized in each tissue, their expression is often analyzed together as NUCB2. The metabolic function of NUCB2/NESF-1 is related to food intake, glucose metabolism, and the regulation of immune, cardiovascular and endocrine systems. Recently, it has been demonstrated that high expression of NUCB2/NESF-1 is associated with poor outcomes and promotes cell proliferation, migration, and invasion in, e.g., breast, colon, prostate, endometrial, thyroid, bladder cancers, or glioblastoma. Interestingly, nesfatin-1 is also considered an inhibitor of the proliferation of human adrenocortical carcinoma and ovarian epithelial carcinoma cells. These conflicting results make NUCB2/NESF-1 an interesting target of study in the context of cancer progression. The present review is the first to describe NUCB2/NESF-1 as a new prognostic and predictive marker in cancers.  相似文献   
109.
Biodegradable polymers of poly(lactic acid) (PLLA) and synthesized in‐house poly(trimethylene carbonate) (PTMC) with admixture of water‐soluble methyl cellulose (MC) were used for development of nerve guidance tubes for peripheral nervous system regeneration after injury. Fabrication method involved phase separation of viscous dixane solution of polymers mixture seat on a rod in a proper nonsolvent, which resulted in tubular structure of large porosity. Influence of electron beam sterilization on molecular weight, thermal properties of the polymers, and mechanical performance of the tubes was evaluated. Admixture of hydrophilic MC to synthetic polymers resulted in modification of mechanical properties of the channels. Extraction of MC showed potential of the tubes for releasing water‐soluble bioactive molecules, such as for instance growth factors. Basic in vitro MTT and LDH assays showed no cytotoxic effect of manufactured tubes, therefore, animal experimentations may be considered. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
110.
In this study the milling and baking characteristics of ten strains of spelt wheat (Triticum aestivum ssp. spelta) originated from Polish breeding were shown. Evaluation of the grain included test weight, vitreousness and hardness. White spelt flour with extraction rate of 65–70% was characterized through the analyses of ash, protein, wet gluten and starch contents as well as Farinograph test, Amylograph test and falling number. Most of spelt wheat varieties investigated demonstrated good milling properties and high baking quality. The spelt breads were analyzed for their potential beneficial components, including total phenolic compounds (TPC) and flavonoids (TF), tocopherols (T) and tocotrienols (T3), inositol phosphates (IP) and reduced (GSH) and oxidized (GSSG) glutathione, and then compared to commercial wheat roll based on wheat flour with extraction rate of approximately 70%. The comparison of the bioactive compounds content between spelt breads and wheat showed a similar level of TPC, TF and GSH. The tocopherols and tocotrienols content in spelt bread was about twice lower when compared to wheat roll. Moreover, spelt wheat bread formulated from flour originated from STH 915 strain showed higher content of inositol phosphates when compared to wheat roll and to those breads from flour of STH 975 and STH 974 strains.  相似文献   
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