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251.
Nadine Ansorge Christian Dannecker Udo Jeschke Elisa Schmoeckel Helene Hildegard Heidegger Aurelia Vattai Maximiliane Burgmann Bastian Czogalla Sven Mahner Sophie Fuerst 《International journal of molecular sciences》2022,23(9)
Vulvar cancer incidence numbers have been steadily rising over the past decades. In particular, the number of young patients with vulvar cancer has recently increased. Therefore, the need to identify new prognostic factors and, in addition, therapeutic options for vulvar carcinoma is more apparent. The aim of this study was to analyze the influx of COX-2 positive tumor-infiltrating lymphocytes and monocytes and their influence on prognosis. Using subtyping by immunofluorescence, the majority of COX-2 expressing immune cells were identified as FOXP3-positive regulatory T cells. In addition, peri- and intra-tumoral macrophages in the same tumor tissue were detected simultaneously as M2-polarized macrophages. COX-2 positive immune cells were independent negative prognostic markers in long-term overall survival of patients with vulvar cancer. These results show an influence of immune cell infiltration for vulvar carcinoma patients. Immune cell infiltration and immune checkpoint expression may, therefore, become interesting targets for further research on new vulvar cancer treatment strategies. 相似文献
252.
Ziya S. Aliev Sabina S. Musayeva Mahammad B. Babanly 《Journal of Phase Equilibria and Diffusion》2017,38(6):887-896
The phase relationships in the Sb-S-I ternary system were determined experimentally over entire concentration range by means of differential thermal analysis (DTA) and x-ray diffraction (XRD) techniques. Two quasi-binary, three isopleth sections, 300 K isothermal section and liquidus surface projection of the system were revised. The primary crystallization fields of all existing phases, the types and coordinates of all invariant and monovariant equilibria were determined. The electromotive force measurements (EMF) method was used to calculate the partial molar functions of antimony in alloys and the standard integral thermodynamic functions of SbSI. 相似文献
253.
Sabina Kramar Vesna Zalar Maja Urosevic Wilfried Körner Alenka Mauko Breda Mirti? Judita Lux Ana Mladenovi? 《Materials Characterization》2011,62(11):1042-1057
This study deals with the characterization of mortars collected from bath complex of the Roman villa rustica from an archeological site near Mošnje (Slovenia). The mortar layers of the mosaics, wall paintings and mortar floors were investigated. A special aggregate consisting of brick fragments was present in the mortars studied. The mineralogical and petrographic compositions of the mortars were determined by means of optical microscopy, X-ray powder diffraction and FTIR spectroscopy. Analysis of aggregate–binder interfaces using SEM-EDS revealed various types of reactivity rims. In order to assess the hydraulic characteristics of the mortars, the acid-soluble fractions were determined by ICP-OES. Furthermore, the results of Hg-porosimetry and gas sorption isotherms showed that mortars with a higher content of brick fragments particles exhibited a higher porosity and a greater BET surface area but a lower average pore diameter compared to mortars lacking this special aggregate. 相似文献
254.
Sabina Alessi Maria Di Filippo Clelia Dispenza Maria Letizia Focarete Chiara Gualandi Roberto Palazzetti Giuseppe Pitarresi Andrea Zucchelli 《Polymer Composites》2015,36(7):1303-1313
Nylon 6,6 electrospun nanofibrous membranes interleaved in “high performance” Carbon Fiber Reinforced Polymer (CFRP) laminates have been proposed as a means to provide a high threshold value to delamination on structural sites where composites are more prone to develop such failure. A model, highly crosslinked, thus inherently brittle, epoxy matrix was selected for its high Young's modulus and glass transition temperature exceeding 250°C. The influence of the Nylon 6,6 nanofibers on the curing behavior of the matrix and on the thermal and dynamic mechanical properties of the cured resin was investigated. These properties were related to the features of the epoxy resin and of the resin impregnated nanofibrous mat. Finally, the delamination behavior of the composite laminates interleaved with Nylon interleaves with different thicknesses was studied through Mode I delamination tests on Double Cantilever Beam (DCB) samples. The results show that the initial Mode I fracture toughness was increased up to about 50% by the presence of the thin mat interleaf. POLYM. COMPOS., 36:1303–1313, 2015. © 2014 Society of Plastics Engineers 相似文献
255.
Jasmina Barakovi Husi Sabina Barakovi Enida Cero Nina Slamnik Merima Ouz Azer Dedovi Osman Zup
i 《International Journal of Network Management》2020,30(3)
This paper presents a quality of experience (QoE) conceptual model to the context of unified communications (UC) through summary, classification, and discussion of multiple influence factors (IFs) and dimensions affecting it. A deep and comprehensive understanding of the IFs and their impact on QoE for a given service is an essential precondition for successful QoE management with the overall goal of prominently optimizing end‐user QoE, while making efficient use of network resources and maintaining a satisfied user base. The proposed conceptual model was used to conduct a qualitative meta‐analytical review of selected papers. The results of the qualitative review include various IFs, QoE dimensions, and key findings in the form of research recommendations for QoE in the context of UC. 相似文献
256.
Colombetti G Checcucci G Lucia S Usai C Ramoino P Bianchini P Pesce M Vicidomini G Diaspro A 《Microscopy research and technique》2007,70(12):1028-1033
In this study we report for the first time the localization of a photoreceptor pigment in the cilia of the colored heterotrich ciliates Blepharisma japonicum red and blue form, Fabrea salina, and Stentor coeruleus, as result of a confocal microscopy investigation. Optical sectioning confocal microscopy has been used for studying the spatial distribution of the pigment in the cell body, surprisingly showing that, besides its expected presence in the cortical region immediately below the cell membrane, it is located in the cilia too. In order to ascertain possible differences in the pigment fluorescence properties along the cell body, we have measured emission spectra from different parts of it (anterior, posterior, and cilia). Our results clearly indicate that in all cases the spectra are the same, within experimental errors. Finally, we have evaluated the pigment relative fluorescence efficiency of these ciliates. In an ordered scale from lower to greater efficiency, we have S. coeruleus, B. japonicum blue, B. japonicum red, and F. salina. The possible implications of our findings for the process of photosensory transduction are discussed. 相似文献
257.
LiFePO4/C was prepared by solid-state reaction from Li3PO4, Fe3(PO4)2·8H2O, carbon and glucose in a few minutes in a scientific MW (microwave) oven with temperature and power control. The material was characterized by X-ray diffraction, scanning electron microscopy and by TGA analysis to evaluate carbon content. The electrochemical characterization as positive electrode in EC (ethylene carbonate)–DMC (dimethylcarbonate) 1 M LiPF6 was performed by galvanostatic charge–discharge cycles at C/10 to evaluate specific capacity and by sequences of 10 s discharge–charge pulses, at different high C-rates (5–45C) to evaluate pulse-specific power in simulate operative conditions for full-HEV application. The maximum pulse-specific power and, particularly, pulse efficiency values are quite high and make MW synthesis a very promising route for mass production of LiFePO4/C for full-HEV batteries at low energy costs. 相似文献
258.
Ivan Kelnar Ümitcan Bal Alexander Zhigunov Ludmila Kaprálková Ivan Fortelný Sabina Krejčíková Jana Kredatusová Jiří Dybal Miroslav Janata Mohammadreza Nofar 《应用聚合物科学杂志》2019,136(24):47660
Modification of microfibrillar composites (MFCs) by nanofillers shows important effects of its localization on performance. This work deals with control of migration/localization of amine-modified graphite nanoplatelets (GNPAs) in the HDPE/PA6 system through their in situ coupling. GNPA/HDPE linking also leads to complex morphology of PA6 fibers. Although such control of GNPA localization and migration in MFC is limited, marked variations of properties, including decrease with high draw ratio, occurs. This is in spite of the fact that structure and crystallinity are comparable with that of the polymer/GNPA adduct. The reason is a more pronounced negative effect of presence of the GNP adducts in the fiber surface layer on HDPE crystallinity, in comparison with neat GNP, that is, formation of “soft” interface. The negative effects were markedly eliminated by pre-blending and coupling of GNPA in both polymer phases. Results confirm more effective control of MFC performance by in situ coupling of GNPA with polymer components in comparison with a nonreactive system. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47660. 相似文献
259.
Antonio Gnoni Antonella Licchetta Aldo Scarpa Amalia Azzariti Anna Elisabetta Brunetti Gianni Simone Patrizia Nardulli Daniele Santini Michele Aieta Sabina Delcuratolo Nicola Silvestris 《International journal of molecular sciences》2013,14(10):19731-19762
Pancreatic adenocarcinoma displays a variety of molecular changes that evolve exponentially with time and lead cancer cells not only to survive, but also to invade the surrounding tissues and metastasise to distant sites. These changes include: genetic alterations in oncogenes and cancer suppressor genes; changes in the cell cycle and pathways leading to apoptosis; and also changes in epithelial to mesenchymal transition. The most common alterations involve the epidermal growth factor receptor (EGFR) gene, the HER2 gene, and the K-ras gene. In particular, the loss of function of tumor-suppressor genes has been documented in this tumor, especially in CDKN2a, p53, DPC4 and BRCA2 genes. However, other molecular events involved in pancreatic adenocarcinoma pathogenesis contribute to its development and maintenance, specifically epigenetic events. In fact, key tumor suppressors that are well established to play a role in pancreatic adenocarcinoma may be altered through hypermethylation, and oncogenes can be upregulated secondary to permissive histone modifications. Indeed, factors involved in tumor invasiveness can be aberrantly expressed through dysregulated microRNAs. This review summarizes current knowledge of pancreatic carcinogenesis from its initiation within a normal cell until the time that it has disseminated to distant organs. In this scenario, highlighting these molecular alterations could provide new clinical tools for early diagnosis and new effective therapies for this malignancy. 相似文献
260.
Voegelin A Jacquat O Pfister S Barmettler K Scheinost AC Kretzschmar R 《Environmental science & technology》2011,45(1):255-261
The long-term speciation of Zn in contaminated soils is strongly influenced by soil pH, clay, and organic matter content as well as Zn loading. In addition, the type of Zn-bearing contaminant entering the soil may influence the subsequent formation of pedogenic Zn species, but systematic studies on such effects are currently lacking. We therefore conducted a soil incubation study in which four soils, ranging from strongly acidic to calcareous, were spiked with 2000 mg/kg Zn using either ZnO (zincite) or ZnS (sphalerite) as the contamination source. The soils were incubated under aerated conditions in moist state for up to four years. The extractability and speciation of Zn were assessed after one, two, and four years using extractions with 0.01 M CaCl(2) and Zn K-edge X-ray absorption fine structure (XAFS) spectroscopy, respectively. After four years, more than 90% of the added ZnO were dissolved in all soils, with the fastest dissolution occurring in the acidic soils. Contamination with ZnO favored the formation of Zn-bearing layered double hydroxides (LDH), even in acidic soils, and to a lesser degree Zn-phyllosilicates and adsorbed Zn species. This was explained by locally elevated pH and high Zn concentrations around dissolving ZnO particles. Except for the calcareous soil, ZnS dissolved more slowly than ZnO, reaching only 26 to 75% of the added ZnS after four years. ZnS dissolved more slowly in the two acidic soils than in the near-neutral and the calcareous soil. Also, the resulting Zn speciation was markedly different between these two pairs of soils: Whereas Zn bound to hydroxy-interlayered clay minerals (HIM) and octahedrally coordinated Zn sorption complexes prevailed in the two acidic soils, Zn speciation in the neutral and the calcareous soil was dominated by Zn-LDH and tetrahedrally coordinated inner-sphere Zn complexes. Our results show that the type of Zn-bearing contaminant phase can have a significant influence on the formation of pedogenic Zn species in soils. Important factors include the rate of Zn release from the contaminant phases and effects of the contaminant phase on bulk soil properties and on local chemical conditions around weathering contaminant particles. 相似文献