Уровень владения английским языком студентов 1 курса ТПУ (по результатам независимого входного тестирования)

В статье представлен сравнительный анализ уровня владения английским языком студентов 1 курса в начале обучения в Национальном исследовательском Томском политехническом университете в 2019-2020 и 2021-2022 учебных годах. Рассмотрены возможные причины снижения уровня владения языком в эпоху COVID-19

A unique biofilm in human deep mycoses: fungal amyloid is bound by host serum amyloid P component

Background/Objectives We have demonstrated the presence of Candida cell surface amyloids that are important in aggregation of fungi and adherence to tissue. Fungal amyloid was present in invasive human candidal infections and host serum amyloid P component (SAP) bound to the fungal amyloid. SAP is a protease-resistant glycoprotein that binds avidly to amyloid and interferes with host defence, especially against bacterial pathogens for which neutrophils are important. In this study, we investigated whether biofilm of fungal amyloid and SAP was a feature of other disseminated fungal infections. Methods Tissue specimens from 15 autopsies were systematically evaluated with multiple histochemical stains including thioflavin T and Congo red (dyes that stain amyloid), as well as antibody to SAP. We studied specimens with disseminated aspergillosis, mucormycosis and coccidioidomycosis. The structure of the lesions, host inflammatory cells and the presence of fungal amyloid and SAP were determined. Results The structure of the lesions was characteristic in aspergillosis (‘starburst’) and mucormycosis (closely apposed bundles of hyphae). Host inflammatory cells were absent or few in number within these lesions. In Coccidioides lesions, host inflammation was sparse as well. Fungal amyloid was a prominent feature of all lesions along with abundant SAP bound to hyphae and spherules. Fungal amyloid and SAP perhaps contributed to persistence in caseous necrosis lesions. SAP also bound to Aspergillus and Mucorales amyloid in vitro. Conclusions A biofilm including amyloid and SAP is present in invasive fungal infections. This biofilm may dampen host defence leading to the characteristic sparse inflammatory reaction found in these infections

A Hyperbaric Aerodynamic Levitator For Containerless Materials Research

A hyperbaric aerodynamic levitator has been developed for containerless materials research at specimen temperatures exceeding 2000 °C and pressures up to 10.3 MPa (1500 psi). This report describes the prototype instrument design and observations of the influence of specimen size, density, pressure, and flow rate on levitation behavior. The effect of pressure on heat transfer was also assessed by studying the heating and cooling behavior of levitated Al2O3 liquids. A threefold increase in the convective heat transfer coefficient was estimated as pressure increased to 10.3 MPa. The results demonstrate that hyperbaric aerodynamic levitation is a promising technique for containerless materials research at high gas pressures

Conductive interpenetrating networks of polypyrrole and polycaprolactone encourage electrophysiological development of cardiac cells

Conductive and electroactive polymers have the potential to enhance engineered cardiac tissue function. In this study, an interpenetrating network of the electrically-conductive polymer polypyrrole (PPy) was grown within a matrix of flexible polycaprolactone (PCL) and evaluated as a platform for directing the formation of functional cardiac cell sheets. PCL films were either treated with sodium hydroxide to render them more hydrophilic and enhance cell adhesion or rendered electroactive with PPy grown via chemical polymerization yielding PPy–PCL that had a resistivity of 1.0 ± 0.4 kΩ cm, which is similar to native cardiac tissue. Both PCL and PPy–PCL films supported cardiomyocyte attachment; increasing the duration of PCL pre-treatment with NaOH resulted in higher numbers of adherent cardiomyocytes per unit area, generating cell densities which were more similar to those on PPy–PCL films (1568 ± 126 cells mm−2, 2880 ± 439 cells mm−2, 3623 ± 456 cells mm−2 for PCL with 0, 24, 48 h of NaOH pretreatment, respectively; 2434 ± 166 cells mm−2 for PPy–PCL). When cardiomyocytes were cultured on the electrically-conductive PPy–PCL, more cells were observed to have peripheral localization of the gap junction protein connexin-43 (Cx43) as compared to cells on NaOH-treated PCL (60.3 ± 4.3% vs. 46.6 ± 5.7%). Cx43 gene expression remained unchanged between materials. Importantly, the velocity of calcium wave propagation was faster and calcium transient duration was shorter for cardiomyocyte monolayers on PPy–PCL (1612 ± 143 μm/s, 910 ± 63 ms) relative to cells on PCL (1129 ± 247 μm/s, 1130 ± 20 ms). In summary, PPy–PCL has demonstrated suitability as an electrically-conductive substrate for culture of cardiomyocytes, yielding enhanced functional properties; results encourage further development of conductive substrates for use in differentiation of stem cell-derived cardiomyocytes and cardiac tissue engineering applications. Statement of Significance Current conductive materials for use in cardiac regeneration are limited by cytotoxicity or cost in implementation. In this manuscript, we demonstrate for the first time the application of a biocompatible, conductive polypyrrole–polycaprolactone film as a platform for culturing cardiomyocytes for cardiac regeneration. This study shows that the novel conductive film is capable of enhancing cell–cell communication through the formation of connexin-43, leading to higher velocities for calcium wave propagation and reduced calcium transient durations among cultured cardiomyocyte monolayers. Furthermore, it was demonstrated that chemical modification of polycaprolactone through alkaline-mediated hydrolysis increased overall cardiomyocyte adhesion. The results of this study provide insight into how cardiomyocytes interact with conductive substrates and will inform future research efforts to enhance the functional properties of cardiomyocytes, which is critical for their use in pharmaceutical testing and cell therapy

Serum Amyloid P Component Binds Fungal Surface Amyloid and Decreases Human Macrophage Phagocytosis and Secretion of Inflammatory Cytokines

In patients with invasive fungal diseases, there is often little cellular inflammatory response. We tested the idea that binding of the human constitutive plasma protein serum amyloid P component (SAP) (also called PTX2) to Candida albicans dampens the innate immune response to this fungus. Many pathogenic fungi have cell surface amyloid-like structures important for adhesion and biofilm formation. Human SAP bound to fungi that expressed functional cell surface amyloid, but SAP had minimal binding to fungi with reduced expression of cell surface amyloid. In the absence of SAP, phagocytosis of fungi by human macrophages was potentiated by expression of amyloid on the fungi. SAP binding to fungi inhibited their phagocytosis by macrophages. Macrophages pretreated with SAP displayed reduced fungal phagocytosis, reduced secretion of inflammatory cytokines (IFN, IL-6, and TNF), and increased secretion of the anti-inflammatory cytokine IL-10. SAP bound to fungi or added to the medium upregulated the expression of the antiinflammatory receptor CD206 on macrophages. These findings suggest that SAP bound to amyloid-like structures on fungal cells dampens the host cellular immune response in fungal diseases such as invasive candidiasis

Peptide Detection of Fungal Functional Amyloids in Infected Tissue

Many fungal cell adhesion proteins form functional amyloid patches on the surface of adhering cells. The Candida albicans Agglutinin-like sequence (Als) adhesins are exemplars for this phenomenon, and have amyloid forming sequences that are conserved between family members. The Als5p amyloid sequence mediates amyloid fibril formation and is critical for cell adhesion and biofilm formation, and is also present in the related adhesins Als1p and Als3p. We have developed a fluorescent peptide probe containing the conserved Als amyloid-forming sequence. This peptide bound specifically to yeast expressing Als5p, but not to cells lacking the adhesin. The probe bound to both yeast and hyphal forms of C. albicans. Δals1/Δals3 single and double deletion strains exhibited reduced fluorescence, indicating that probe binding required expression of these proteins. Additionally, the Als peptide specifically stained fungal cells in abscesses in autopsy sections. Counterstaining with calcofluor white showed colocalization with the amyloid peptide. In addition, fungi in autopsy sections derived from the gastrointestinal tract showed colocalization of the amyloid-specific dye thioflavin T and the fluorescent peptide. Collectively, our data demonstrate that we can exploit amyloid sequence specificity for detection of functional amyloids in situ

Gated myocardial perfusion SPECT underestimates left ventricular volumes and shows high variability compared to cardiac magnetic resonance imaging -- a comparison of four different commercial automated software packages

Abstract Background We sought to compare quantification of left ventricular volumes and ejection fraction by different gated myocardial perfusion SPECT (MPS) programs with each other and to magnetic resonance (MR) imaging. Methods N = 100 patients with known or suspected coronary artery disease were examined at rest with 99 mTc-tetrofosmin gated MPS and cardiac MR imaging. Left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF) were obtained by analysing gated MPS data with four different programs: Quantitative Gated SPECT (QGS), GE MyoMetrix, Emory Cardiac Toolbox (ECTb) and Exini heart. Results All programs showed a mean bias compared to MR imaging of approximately -30% for EDV (-22 to -34%, p Conclusions Gated MPS, systematically underestimates left ventricular volumes by approximately 30% and shows a high variability, especially for ESV. For EF, accuracy was better, with a mean bias between -15 and 6% of EF. It may be of value to take this into consideration when determining absolute values of LV volumes and EF in a clinical setting.</p

Complete fuzzy scheduling and fuzzy earned value management in construction projects

Complete fuzzy scheduling and fuzzy earned value management in construction projects Por: Luis Ponz-Tienda, Jose; Pellicer, Eugenio; Yepes, Victor JOURNAL OF ZHEJIANG UNIVERSITY-SCIENCE A Volumen: 13 Número: 1 Páginas: 56-68 Fecha de publicación: JAN 2012 Search For Full Text Cerrar abstractCerrar abstract This paper aims to present a comprehensive proposal for project scheduling and control by applying fuzzy earned value. It goes a step further than the existing literature: in the formulation of the fuzzy earned value we consider not only its duration, but also cost and production, and alternatives in the scheduling between the earliest and latest times. The mathematical model is implemented in a prototypical construction project with all the estimated values taken as fuzzy numbers. Our findings suggest that different possible schedules and the fuzzy arithmetic provide more objective results in uncertain environments than the traditional methodology. The proposed model allows for controlling the vagueness of the environment through the adjustment of the alpha-cut, adapting it to the specific circumstances of the project. © Zhejiang University and Springer-Verlag Berlin Heidelberg 2012.The authors want to thank Ms. Doria GIL-SENABRE, Universitat Politecnica de Valencia, Spain, for the support provided.Ponz Tienda, JL.; Pellicer Armiñana, E.; Yepes Piqueras, V. (2012). Complete fuzzy scheduling and fuzzy earned value management in construction projects. Journal of Zhejiang University Science A. 13(1):56-68. https://doi.org/10.1631/jzus.A1100160S566813

Incorporating functional inter-relationships into protein function prediction algorithms

<p>Abstract</p> <p>Background</p> <p>Functional classification schemes (e.g. the Gene Ontology) that serve as the basis for annotation efforts in several organisms are often the source of gold standard information for computational efforts at supervised protein function prediction. While successful function prediction algorithms have been developed, few previous efforts have utilized more than the protein-to-functional class label information provided by such knowledge bases. For instance, the Gene Ontology not only captures protein annotations to a set of functional classes, but it also arranges these classes in a DAG-based hierarchy that captures rich inter-relationships between different classes. These inter-relationships present both opportunities, such as the potential for additional training examples for small classes from larger related classes, and challenges, such as a harder to learn distinction between similar GO terms, for standard classification-based approaches.</p> <p>Results</p> <p>We propose a method to enhance the performance of classification-based protein function prediction algorithms by addressing the issue of using these interrelationships between functional classes constituting functional classification schemes. Using a standard measure for evaluating the semantic similarity between nodes in an ontology, we quantify and incorporate these inter-relationships into the <it>k</it>-nearest neighbor classifier. We present experiments on several large genomic data sets, each of which is used for the modeling and prediction of over hundred classes from the GO Biological Process ontology. The results show that this incorporation produces more accurate predictions for a large number of the functional classes considered, and also that the classes benefitted most by this approach are those containing the fewest members. In addition, we show how our proposed framework can be used for integrating information from the entire GO hierarchy for improving the accuracy of predictions made over a set of base classes. Finally, we provide qualitative and quantitative evidence that this incorporation of functional inter-relationships enables the discovery of interesting biology in the form of novel functional annotations for several yeast proteins, such as Sna4, Rtn1 and Lin1.</p> <p>Conclusion</p> <p>We implemented and evaluated a methodology for incorporating interrelationships between functional classes into a standard classification-based protein function prediction algorithm. Our results show that this incorporation can help improve the accuracy of such algorithms, and help uncover novel biology in the form of previously unknown functional annotations. The complete source code, a sample data set and the additional files for this paper are available free of charge for non-commercial use at <url>http://www.cs.umn.edu/vk/gaurav/functionalsimilarity/</url>.</p