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41.
Functions that optimize Laplacian‐based energies have become popular in geometry processing, e.g. for shape deformation, smoothing, multiscale kernel construction and interpolation. Minimizers of Dirichlet energies, or solutions of Laplace equations, are harmonic functions that enjoy the maximum principle, ensuring no spurious local extrema in the interior of the solved domain occur. However, these functions are only C0 at the constrained points, which often causes smoothness problems. For this reason, many applications optimize higher‐order Laplacian energies such as biharmonic or triharmonic. Their minimizers exhibit increasing orders of continuity but lose the maximum principle and show oscillations. In this work, we identify characteristic artifacts caused by spurious local extrema, and provide a framework for minimizing quadratic energies on manifolds while constraining the solution to obey the maximum principle in the solved region. Our framework allows the user to specify locations and values of desired local maxima and minima, while preventing any other local extrema. We demonstrate our method on the smoothness energies corresponding to popular polyharmonic functions and show its usefulness for fast handle‐based shape deformation, controllable color diffusion, and topologically‐constrained data smoothing. 相似文献
42.
The present study examined the impact of a judicial warning, witness age, and the method of testimony presentation on mock jurors' perceptions of credibility of witnesses and accused, and on guilty verdicts. The participants were 435 undergraduate university students who listened to an audio-taped summary of a theft trial followed by abbreviated instructions to the jury. Witness age was 7, 10, or 23, the jury warning was either present or absent when witnesses were children, and the testimony by the prosecution eyewitness and accused were either presented or summarized. For the taped testimony conditions, the mock witnesses and the accused read a fact pattern describing the events in the case and were audiotaped as they answered a series of questions, which constituted direct and cross-examination. The testimony of the 7-year-old child, compared to the 10-year-old, was associated with lower cognitive competence and higher suggestibility, but also with higher accuracy of recall (lower mistaken recollection) and lower credibility of accused. The pattern of results for appraisal of the older child was more similar to that of an adult witness. The young adult was judged to be less trustworthy than children of either age. While the presence of a warning had no impact on guilty verdicts when a 7-year-old was a witness, there were fewer guilty verdicts when a witness was 10 years old. Participants also made fewer guilty verdicts when a young adult's testimony, compared to conditions involving child witnesses, was presented, but not when it was summarized. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
Achim Müller Olga Heim M. Panneerselvam Monika Willert-Porada 《Materials Research Bulletin》2005,40(12):2153-2169
A modified microwave-assisted polyol method was applied to prepare nanoparticulate ceramic powders of different oxides, i.e. Gd2O3, AlO(OH) (boehmite) and TiO2. Due to the good dielectric properties of the utilised solvents, such as ethylene glycol, diethylene glycol and 1,4 butanediol, a significant decrease in reaction time was achieved under microwave heating. In the case of AlO(OH) and Gd2O3, <5 nm primary particle size were obtained. Boehmite was found to be intercalated with the solvent. The general applicability of the process is shown and the advantages in terms of properties and processibility are described. The powders thus prepared were investigated using X-ray diffractometry, electron microscopy and physisorption. 相似文献
44.
Reliable Computing - 相似文献
45.
Maria V. Sukhanova Rashid O. Anarbaev Ekaterina A. Maltseva David Pastr Olga I. Lavrik 《International journal of molecular sciences》2022,23(21)
Fused in sarcoma (FUS) is involved in the regulation of RNA and DNA metabolism. FUS participates in the formation of biomolecular condensates driven by phase transition. FUS is prone to self-aggregation and tends to undergo phase transition both with or without nucleic acid polymers. Using dynamic light scattering and fluorescence microscopy, we examined the formation of FUS high-order structures or FUS-rich microphases induced by the presence of RNA, poly(ADP-ribose), ssDNA, or dsDNA and evaluated effects of some nucleic-acid-binding proteins on the phase behavior of FUS–nucleic acid systems. Formation and stability of FUS-rich microphases only partially correlated with FUS’s affinity for a nucleic acid polymer. Some proteins—which directly interact with PAR, RNA, ssDNA, and dsDNA and are possible components of FUS-enriched cellular condensates—disrupted the nucleic-acid-induced assembly of FUS-rich microphases. We found that XRCC1, a DNA repair factor, underwent a microphase separation and formed own microdroplets and coassemblies with FUS in the presence of poly(ADP-ribose). These results probably indicated an important role of nucleic-acid-binding proteins in the regulation of FUS-dependent formation of condensates and imply the possibility of the formation of XRCC1-dependent phase-separated condensates in the cell. 相似文献
46.
Olga A. Krasnova Vitaly V. Gursky Alina S. Chabina Karina A. Kulakova Larisa L. Alekseenko Alexandra V. Panova Sergey L. Kiselev Irina E. Neganova 《International journal of molecular sciences》2022,23(21)
The ability of human pluripotent stem cells for unlimited proliferation and self-renewal promotes their application in the fields of regenerative medicine. The morphological assessment of growing colonies and cells, as a non-invasive method, allows the best clones for further clinical applications to be safely selected. For this purpose, we analyzed seven morphological parameters of both colonies and cells extracted from the phase-contrast images of human embryonic stem cell line H9, control human induced pluripotent stem cell (hiPSC) line AD3, and hiPSC line HPCASRi002-A (CaSR) in various passages during their growth for 120 h. The morphological phenotype of each colony was classified using a visual analysis and associated with its potential for pluripotency and clonality maintenance, thus defining the colony phenotype as the control parameter. Using the analysis of variance for the morphological parameters of each line, we showed that selected parameters carried information about different cell lines and different phenotypes within each line. We demonstrated that a model of classification of colonies and cells by phenotype, built on the selected parameters as predictors, recognized the phenotype with an accuracy of 70–75%. In addition, we performed a qRT-PCR analysis of eleven pluripotency markers genes. By analyzing the variance of their expression in samples from different lines and with different phenotypes, we identified group-specific sets of genes that could be used as the most informative ones for the separation of the best clones. Our results indicated the fundamental possibility of constructing a morphological portrait of a colony informative for the automatic identification of the phenotype and for linking this portrait to the expression of pluripotency markers. 相似文献
47.
Olga Snytnikova Yuri Tsentalovich Renad Sagdeev Nataliya Kolosova Oyuna Kozhevnikova 《International journal of molecular sciences》2022,23(21)
Autophagy is involved in the maintenance of cellular homeostasis and the removal of damaged proteins and organelles and is necessary to maintain cell metabolism in conditions of energy and nutrient deficiency. A decrease in autophagic activity plays an important role in age-related diseases. However, the metabolic response to autophagy modulation remains poorly understood. Here, we for the first time explored the effects of (1) autophagy activation by 48 h fasting, (2) inhibition by chloroquine (CQ) treatment, and (3) combined effects of fasting and CQ on the quantitative composition of metabolites in the blood serum of senescent-accelerated OXYS and control Wistar rats at the age of 4 months. By means of high-resolution 1H NMR spectroscopy, we identified the quantitative content of 55 serum metabolites, including amino acids, organic acids, antioxidants, osmolytes, glycosides, purine, and pyrimidine derivatives. Groups of 48 h fasting (induction of autophagy), CQ treatment (inhibition of autophagy), and combined effects (CQ + fasting) are clearly separated from control groups by principal component analysis. Fasting for 48 h led to significant changes in the serum metabolomic profile, primarily affecting metabolic pathways related to fatty acid metabolism, and led to metabolism of several amino acids. Under CQ treatment, the most affected metabolites were citrate, betaine, cytidine, proline, tryptophan, glutamate, and mannose. As shown by two-way ANOVA, for many metabolites the effects of autophagy modulation depend on the animal genotype, indicating a dysregulation of metabolome reactivity in OXYS rats. Thus, the metabolic responses to modulation of autophagy in OXYS rats and Wistar rats are different. Altered metabolites in OXYS rats may serve as potential biomarkers of the manifestation of the signs of accelerated aging. Metabolic signatures characteristic to fasting and CQ treatment revealed in this work might provide a better understanding of the connections between metabolism and autophagy. 相似文献
48.
Aleksandra Ochneva Yana Zorkina Olga Abramova Olga Pavlova Valeriya Ushakova Anna Morozova Eugene Zubkov Konstantin Pavlov Olga Gurina Vladimir Chekhonin 《International journal of molecular sciences》2022,23(22)
Mental disorders represent common brain diseases characterized by substantial impairments of social and cognitive functions. The neurobiological causes and mechanisms of psychopathologies still have not been definitively determined. Various forms of brain proteinopathies, which include a disruption of protein conformations and the formation of protein aggregates in brain tissues, may be a possible cause behind the development of psychiatric disorders. Proteinopathies are known to be the main cause of neurodegeneration, but much less attention is given to the role of protein impairments in psychiatric disorders’ pathogenesis, such as depression and schizophrenia. For this reason, the aim of this review was to discuss the potential contribution of protein illnesses in the development of psychopathologies. The first part of the review describes the possible mechanisms of disruption to protein folding and aggregation in the cell: endoplasmic reticulum stress, dysfunction of chaperone proteins, altered mitochondrial function, and impaired autophagy processes. The second part of the review addresses the known proteins whose aggregation in brain tissue has been observed in psychiatric disorders (amyloid, tau protein, α-synuclein, DISC-1, disbindin-1, CRMP1, SNAP25, TRIOBP, NPAS3, GluA1, FABP, and ankyrin-G). 相似文献
49.
Olena V. Moshynets Ianina Pokholenko Olga Iungin Geert Potters Andrew J. Spiers 《International journal of molecular sciences》2022,23(23)
Pseudomonas fluorescens SBW25 is a model soil- and plant-associated bacterium capable of forming a variety of air–liquid interface biofilms in experimental microcosms and on plant surfaces. Previous investigations have shown that cellulose is the primary structural matrix component in the robust and well-attached Wrinkly Spreader biofilm, as well as in the fragile Viscous Mass biofilm. Here, we demonstrate that both biofilms include extracellular DNA (eDNA) which can be visualized using confocal laser scanning microscopy (CLSM), quantified by absorbance measurements, and degraded by DNase I treatment. This eDNA plays an important role in cell attachment and biofilm development. However, exogenous high-molecular-weight DNA appears to decrease the strength and attachment levels of mature Wrinkly Spreader biofilms, whereas low-molecular-weight DNA appears to have little effect. Further investigation with CLSM using an amyloid-specific fluorophore suggests that the Wrinkly Spreader biofilm might also include Fap fibers, which might be involved in attachment and contribute to biofilm strength. The robust nature of the Wrinkly Spreader biofilm also allowed us, using MALDI-TOF mass spectrometry, to identify matrix-associated proteins unable to diffuse out of the structure, as well as membrane vesicles which had a different protein profile compared to the matrix-associated proteins. CLSM and DNase I treatment suggest that some vesicles were also associated with eDNA. These findings add to our understanding of the matrix components in this model pseudomonad, and, as found in other biofilms, biofilm-specific products and material from lysed cells contribute to these structures through a range of complex interactions. 相似文献
50.
Angela Cozma Nicolae Dan Sporis Andrada Luciana Lazar Andrei Buruiana Andreea Maria Ganea Toma Vlad Malinescu Bianca Mihaela Berechet Adriana Fodor Adela Viviana Sitar-Taut Vasile Calin Vlad Vasile Negrean Olga Hilda Orasan 《International journal of molecular sciences》2022,23(18)
Immune checkpoint inhibitors (ICIs) are an important advancement in the field of cancer treatment, significantly improving the survival of patients with a series of advanced malignancies, like melanoma, non-small cell lung cancer (NSCLC), hepatocellular carcinoma (HCC), renal cell carcinoma (RCC), and Hodgkin lymphoma. ICIs act upon T lymphocytes and antigen-presenting cells, targeting programmed cell death protein 1 (PD1), programmed cell death protein ligand 1 (PD-L1), and cytotoxic T-lymphocyte antigen 4 (CTLA-4), breaking the immune tolerance of the T cells against malignant cells and enhancing the body’s own immune response. A variety of cardiac-adverse effects are associated with ICI-based treatment, including pericarditis, arrhythmias, cardiomyopathy, and acute coronary syndrome, with myocarditis being the most studied due to its often-unexpected onset and severity. Overall, Myocarditis is rare but presents an immune-related adverse event (irAE) that has a high fatality rate. Considering the rising number of oncological patients treated with ICIs and the severity of their potential adverse effects, a good understanding and continuous investigation of cardiac irAEs is of the utmost importance. This systematic review aimed to revise recent publications (between 2016–2022) on ICI-induced cardiac toxicities and highlight the therapeutical approach and evolution in the selected cases. 相似文献