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1.
Indre Jasineviciute Md Nazmul Hasan Juozas Grigas Arnoldas Pautienius Arunas Stankevicius Judita Zymantiene Naoki Miura 《International journal of molecular sciences》2023,24(1)
Various microRNAs (miRNAs) present in autologous blood products of canines have not been studied recently. We aimed to elucidate the existence of miRNAs in platelet-rich fibrin (PRF) and the stability of canine autologous blood products under various storage conditions. Total RNAs were isolated from PRF and other autologous blood products following newly adapted protocols used in commercial kits for plasma and tissue samples. Quantitative real-time polymerase chain reaction analysis (qPCR) was used to detect miRNAs in autologous blood products. The miR-16, miR-21, miR-155, and miR-146a were abundant in PRF and other autologous blood products of canines. Furthermore, we found they could maintain stability under protracted freezing temperatures of −30 °C for at least one month. Our findings revealed that PRF might be a stable resource for various canine miRNAs. 相似文献
2.
Martial Degbia Bruno Schmaltz Johann Bouclé Juozas V Grazulevicius François Tran‐Van 《Polymer International》2014,63(8):1387-1393
The synthesis of new organic hole transporting materials (HTMs) based on 3,6‐disubstituted 9H‐carbazole‐3,6‐diamine,N,N,N′,N′‐tetraphenyl‐9‐(4‐methoxyphenyl) derivatives and their applications in solid state dye sensitizer solar cells (DSSCs) are described. The effect of the methoxy group localized on the para position of the diphenylamine moieties on the thermal, electronic and electrochemical properties and photovoltaic performance is discussed. In solid state DSSCs, utilization of the aforementioned HTMs in combination with the dye D102 (TiO2/D102/HTM/Au) shows a positive influence of the methoxy group on the photovoltaic conversion efficiency compared with unsubstituted diphenylamine grafted groups. A study on the concentration of the HTM is also carried out and shows an optimal concentration around 200 mg mL?1. Without further optimization, the best device gives a power conversion efficiency of 1.75% under AM 1.5 solar irradiation (100 mW cm?2). 相似文献
3.
Ausra Tomkeviciene Gabija Puckyte Juozas Vidas Grazulevicius Martial Degbia Francois Tran-Van Bruno Schmaltz Vygintas Jankauskas Johann Bouclé 《Synthetic Metals》2012
The synthesis and properties of glass-forming diphenylamino-substituted derivatives of 9-phenylcarbazole with methoxy groups in the different position of diphenylamino moieties are reported. A comparative study on their thermal, optical, photoelectrical and electrochemical properties is presented. The synthesized compounds exhibit high thermal stability with 5% weight loss temperatures ranging from 344 to 475 °C. The derivatives absorb electromagnetic irradiation in the range of 225–425 nm with the band gaps of 2.94–3.08 eV. The ionization energies of the synthesized compounds range from 5.04 to 5.56 eV. The lowest ionization energies and band gaps are observed for compounds containing para methoxy-substituted phenyl rings of diphenylamino moieties and for disubstituted carbazole derivatives. Charge-transporting properties of the selected compounds were tested by time-of-flight technique. Hole drift mobilities in the amorphous layers of the materials reach 10−3 cm2/V s at high electric fields. The derivatives were tested as hole transport materials in solid-state dye sensitized solar cells and showed conversion efficiency up to 0.54%. 相似文献
4.
Rokas Lukosevicius Simonas Juzenas Violeta Salteniene Ugne Kulokiene Justina Arstikyte Georg Hemmrich-Stanisak Andre Franke Alexander Link Paulius Ruzgys Saulius Satkauskas Henrikas Pauzas Tadas Latkauskas Gediminas Kiudelis Francesc Balaguer Juozas Kupcinskas Jurgita Skieceviciene 《International journal of molecular sciences》2022,23(4)
Regulatory changes occurring early in colorectal cancer development remain poorly investigated. Since the majority of cases develop from polyps in the adenoma-carcinoma transition, a search of early molecular features, such as aberrations in miRNA expression occurring prior to cancer development, would enable identification of potentially causal, rather than consequential, candidates in the progression of polyp to cancer. In the current study, by employing small RNA-seq profiling of colon biopsy samples, we described differentially expressed miRNAs and their isoforms in the adenoma-carcinoma transition. Analysis of healthy-adenoma-carcinoma sequence in an independent validation group enabled us to identify early deregulated miRNAs including hsa-miR-1246 and hsa-miR-215-5p, the expressions of which are, respectively, gradually increasing and decreasing. Loss-of-function experiments revealed that inhibition of hsa-miR-1246 lead to reduced cell viability, colony formation, and migration rate, thereby indicating an oncogenic effect of this miRNA in vitro. Subsequent western blot and luciferase reporter assay provided evidence of hsa-miR-1246 being involved in the regulation of target AXIN2 and CFTR genes’ expression. To conclude, the present study revealed possible involvement of hsa-miR-1246 in early colorectal cancer development and regulation of tumor suppressors AXIN2 and CFTR. 相似文献
5.
Juozas Atkočiūnas Adam Borkowski Jan A. König 《Computer Methods in Applied Mechanics and Engineering》1981,28(3):365-376
A method is proposed for obtaining an upper bound for the displacement which can occur in a structure adapted to a given variable-repeated load. First, the exact formulation of the problem is presented which leads to a problem of optimal control. Then the differential constraints are neglected or replaced by algebraic conditions. The solution of the resulting linear programming problem supplies an upper bound to the exact elastic-plastic deflection. Further approximation can be introduced, if desired, which allows the decomposition of the problem into separate bounds to elastic and plastic parts of displacement.Numerical examples include a two-span continuous beam and a two-storey frame. The first was solved analytically, the second by means of a specially developed computer routine capable of evaluating the displacements at shakedown of arbitrary planar frames or trusses. The results obtained confirm the validity of the small displacement approach. 相似文献
6.
Arturas Kaklauskas Andrej Vlasenko Vidas Raudonis Edmundas Kazimieras Zavadskas Renaldas Gudauskas Mark Seniut Algirdas Juozapaitis Ieva Jackute Loreta Kanapeckiene Silva Rimkuviene Gabrielius Kaklauskas 《Engineering Applications of Artificial Intelligence》2013,26(1):35-50
Students and lecturers would like to know how well students have learned the study materials being taught. A formal test or exam would cause needless stress for students. To resolve this problem, the authors of this article have developed an Intelligent Pupil Analysis (IPA) System. A sufficient amount of studies worldwide prove an interrelation between pupil size and a person's cognitive load. The obtained research results are comparable with the results from other similar studies. The original contribution of this article, compared to the research results published earlier, is as follows: the IPA System developed by the authors is superior to the traditional pupil analysis research due to the integration of pupil analysis with subsystems of decision support, recommender and intelligent tutoring systems and innovative Models of the Model-base, which permit a more detailed analysis of the knowledge attained by a student. This article ends with a case study to demonstrate the practical operation of the IPA System. 相似文献
7.
Structure–properties relationship of hydrazones containing methoxy-substituted triphenylamino groups
V. Mimaite J. Ostrauskaite D. Gudeika J.V. Grazulevicius V. Jankauskas 《Synthetic Metals》2011,161(15-16):1575-1581
We have synthesized a series of hole-transporting dimethoxytriphenylamine-based hydrazones and studied the influence of the position of methoxy groups on the thermal, optical, electrochemical, and photoelectrical properties of the materials. The synthesized compounds form glasses with glass transition temperatures ranging from 32 to 64 °C. Compounds having methoxy groups in the ortho positions of triphenylamino moiety show higher glass transition temperatures than the corresponding derivatives having methoxy substituents in meta or para positions. Ionization potentials of the solid samples of hydrazones range from 5.18 to 5.27 eV. Hydrazones having methoxy substituents in para positions of triphenylamino moiety show superior charge-transporting properties with respect to hydrazones containing methoxy substituents in ortho and meta positions respectively. Molecularly doped bisphenol Z polycarbonate containing 50 wt.% of hydrazones with methoxy substituents in para positions of triphenylamino moiety show time-of-flight hole-drift mobilities approaching 10?4 cm2/(V s) at high electric fields. 相似文献
8.
R. Paspirgelyte J.V. Grazulevicius S. Grigalevicius V. Jankauskas 《Synthetic Metals》2009,159(5-6):487-491
Several N-(2,2-diphenylvinyl)-N,N′-diphenylbenzidine-based derivatives were synthesized by the multi-step synthetic route. Full characterization of their structure is presented. The synthesized materials were examined by various techniques including differential scanning calorimetry, UV spectrometry, electron photoemission and time of flight techniques. The electron photoemission spectra of layers of the amorphous materials showed the ionization potentials of 5.35–5.4 eV. Time-of-flight hole drift mobilities in the amorphous layers of some derivatives exceed 10?3 cm2/V s at high electric fields. 相似文献
9.
Tadas Malinauskas Ingrida Vilionskiene Juozas V Grazulevicius Vytautas Getautis Jose A Reina Jonas Sidaravicius 《Polymer International》2008,57(10):1159-1164
BACKGROUND: Carbazole derivatives are well known to exhibit interesting electro‐ and photo‐active properties due to their hole‐transporting ability, strong absorption in the ultraviolet spectral region and blue‐light emission. One of the most widely studied materials among carbazole‐containing oligomers is poly[9‐(2,3‐epoxypropyl)carbazole] (PEPK). The main field of application of this oligomer is electrophotographic microfilming. It is also used for the manufacture of multicolour slides and in the photothermoplastic recording of information. Unfortunately, due to its high ionization potential, which reaches 5.86 eV, the possibilities of application of this compound in optoelectronic devices are rather limited. RESULTS: PEPK‐based charge transporting oligomers, incorporating hydrazone moieties, are reported. The oligomers were prepared by chemical modification of PEPK. The materials obtained were examined using various techniques including differential scanning calorimetry and ultraviolet, infrared and NMR spectroscopy. Electron photoemission spectra of layers of the synthesized oligomers showed ionization potentials (Ip) in the range 5.4–5.5 eV. CONCLUSION: The synthesized oligomers possess a larger π‐conjugated system and show ionization potentials of ca 5.4 eV. Therefore, they are more suitable for use in optoelectronic devices with quicker photoresponse than unmodified PEPK. Copyright © 2008 Society of Chemical Industry 相似文献
10.
S. Lengvinaite J.V. Grazulevicius S. Grigalevicius B. Zhang Z. Xie 《Reactive and Functional Polymers》2010,70(7):477-481
(Bi)phenyl-substituted carbazoles containing reactive functional groups were synthesized by the multi-step synthetic rout. The monomers were examined by various techniques including thermogravimetry, differential scanning calorimetry, UV and fluorescence spectrometry as well as electron photoemission technique. These derivatives were also tested as hole transporting materials in bilayer OLEDs with Alq3 as the emitter. The devices exhibited promising overall performance with a turn-on voltage of ~3 V, a maximal photometric efficiency of 5.1 cd/A and maximum brightness of 12,200–15,600 cd/m2. 相似文献