116 research outputs found
Синтез та дослідження фізико-хімічних властивостей 2-((5-(феноксиметил)-4-R-1,2,4-триазол-3-іл)тіо)етан-1-олів і їх похідних
The number of new various diseases increases with the development of science and technology. But currently medicine does not have effective ways to overcome this problem. There is a large number of different pharmacological groups of drugs at the pharmaceutical market, but some of them are not available for the Ukrainian consumers. Therefore, the main task of national scientists in the field of pharmaceutical synthesis is the search for new biologically active substances and their further introduction into medical practice as new, low-toxic, original medicines of the Ukrainian production at an affordable price. The aim of our research is the synthesis of a new class of biologically active substances, namely 2-((5-(phenoxymethyl)-4-R-1,2,4-triazol-3-yl)thio)ethan-1- ols and their derivatives. All compounds obtained have been synthesized from 5-(phen-oxymethyl)-4-R-1,2,4- triazol-3-thiones (R = H, C2H5, C6H5) using electrophilic and nucleophilic substitution reactions when heating. The structure of the compounds synthesized has been confirmed by using a modern set of physical and chemical methods such as IR-spectrometry, 1H NMR spectrometry and elemental analysis, and their individuality by high performance liquid chromatography-mass spectrometry. The work in determining the parameters of acute toxicity and biological activity is continued.С развитием научно-технического прогресса увеличивается количество новых разнообразных заболеваний, на преодоление которых медицина сегодня не имеет эффективных методов лечения. На мировом фармацевтическом рынке существует многочисленное количество различных фармакотерапевтических групп лекарственных средств, но не все они доступны украинскому потребителю. Поэтому основной задачей отечественных ученых в области фармацевтического синтеза является поиск новых биологически активных веществ и дальнейшее их внедрение во врачебную практику в качестве новых, малотоксичных, оригинальных лекарственных препаратов украинского производства по доступной цене. Целью нашего исследования является синтез нового класса биологически активных веществ – 2-((5-(феноксиметил)-4-R-1,2,4-триазол-3-ил)тио)этан-1-олов и их производных. Все полученные соединения были синтезированы на основе 5-(феноксиметил)-4-R-1,2,4-триазол-3-тионов (R=H, C2H5, C6H5) с использованием реакций электрофильного и нуклеофильного замещения при нагревании. Строение синтезированных соединений подтверждено комплексным использованием современных фи- зико-химических методов: ИК-спектрофотометрии, 1Н ЯМР-спектрометрии, элементного анализа, а их индивидуальность – ультравысокоэффективной жидкостной хромато-масс-спектрометрии. Про- должается работа по установлению показателей острой токсичности и биологической активности.З розвитком науково-технічного прогресу зростає кількість нових різноманітних захворювань, на подолання яких у медицині не існує на сьогодні ефективних методів лікування. На світовому фармацевтичному ринку існує численна кількість різних фармакотерапевтичних груп лікарських засобів, але не всі вони доступні українському споживачу. Тому основним завданням вітчизняних науковців у галузі фармацевтичного синтезу є пошук нових біологічно активних речовин та подальше їх впровадження у лікарську практику в якості нових, малотоксичних, оригінальних лікарських препаратів українського виробництва за доступною ціною. Метою нашого дослідження є синтез нового класу біологічно активних речовин – 2-((5-(феноксиметил)-4-R-1,2,4-триазол-3-іл)тіо)етан-1-олів та їх похідних. Всі отримані сполуки були синтезовані на основі 5-(феноксиметил)-4-R-1,2,4-триазол-3-тіонів (R = H, C2H5, C6H5) з використанням реакцій електрофільного та нуклеофільного заміщення при нагріванні. Будова синтезованих сполук підтверджена комплексним використанням сучасних фізико-хімічних методів: ІЧ-спектрофотометрії, 1Н ЯМР-спектрометрії та елементного аналізу, а їх індивідуальність – ультрависокоефективною рідинною хромато-мас-спектрометрією. Продовжується робота зі встановлення показників гострої токсичності та біологічної активності
Description of the Magnetic Field and Divergence of Multisolenoid Aharonov-Bohm Potential
Explicit formulas for the magnetic field and divergence of multisolenoid Aharonov-Bohm potential are obtained; the mathematical essence of this potential is explained. It is shown that the magnetic field and divergence of this potential are very singular generalized functions concentrated at a finite number of thin solenoids. Deficiency index is found for the minimal operator generated by the Aharonov-Bohm differential expression
PTCH1+/− Dermal Fibroblasts Isolated from Healthy Skin of Gorlin Syndrome Patients Exhibit Features of Carcinoma Associated Fibroblasts
Gorlin's or nevoid basal cell carcinoma syndrome (NBCCS) causes predisposition to basal cell carcinoma (BCC), the commonest cancer in adult human. Mutations in the tumor suppressor gene PTCH1 are responsible for this autosomal dominant syndrome. In NBCCS patients, as in the general population, ultraviolet exposure is a major risk factor for BCC development. However these patients also develop BCCs in sun-protected areas of the skin, suggesting the existence of other mechanisms for BCC predisposition in NBCCS patients. As increasing evidence supports the idea that the stroma influences carcinoma development, we hypothesized that NBCCS fibroblasts could facilitate BCC occurence of the patients. WT (n = 3) and NBCCS fibroblasts bearing either nonsense (n = 3) or missense (n = 3) PTCH1 mutations were cultured in dermal equivalents made of a collagen matrix and their transcriptomes were compared by whole genome microarray analyses. Strikingly, NBCCS fibroblasts over-expressed mRNAs encoding pro-tumoral factors such as Matrix Metalloproteinases 1 and 3 and tenascin C. They also over-expressed mRNA of pro-proliferative diffusible factors such as fibroblast growth factor 7 and the stromal cell-derived factor 1 alpha, known for its expression in carcinoma associated fibroblasts. These data indicate that the PTCH1+/− genotype of healthy NBCCS fibroblasts results in phenotypic traits highly reminiscent of those of BCC associated fibroblasts, a clue to the yet mysterious proneness to non photo-exposed BCCs in NBCCS patients
Student engagement as a function of environmental complexity in high school classrooms
The purpose of this study was to investigate the linkage between the quality of the learning environment and the quality of students' experience in seven high school classrooms in six different subject areas. The quality of the learning environment was conceptualized in terms of environmental complexity, or the simultaneous presence of environmental challenge and environmental support. The students (N = 108) in each class participated in the Experience Sampling Method (ESM) measuring their engagement and related experiential variables. Concurrently, environmental complexity and its subdimensions were observed and rated from video with a new observational instrument, The Optimal Learning Environments - Observational Log and Assessment (OLE-OLA). Using two-level HLM regression models, ratings from the OLE-OLA were utilized to predict student engagement and experiential variables as measured by the ESM. Results showed that environmental complexity predicted student engagement and sense of classroom self-esteem. Implications for research, theory and practice are discussed
Validation of a Novel Fluorescent Lateral Flow Assay for Rapid Qualitative and Quantitative Assessment of Total Anti-SARS-CoV-2 S-RBD Binding Antibody Units (BAU) from Plasma or Fingerstick Whole-Blood of COVID-19 Vaccinees
Background: Limited commercial LFA assays are available to provide a reliable quantitative measurement of the total binding antibody units (BAU/mL) against the receptor-binding domain of the SARS-CoV-2 spike protein (S-RBD). Aim: This study aimed to evaluate the performance of the fluorescence LFA FinecareTM 2019-nCoV S-RBD test along with its reader (Model No.: FS-113) against the following reference methods: (i) the FDA-approved GenScript surrogate virus-neutralizing assay (sVNT); and (ii) three highly performing automated immunoassays: BioMérieux VIDAS®3, Ortho VITROS®, and Mindray CL-900i®. Methods: Plasma from 488 vaccinees was tested by all aforementioned assays. Fingerstick whole-blood samples from 156 vaccinees were also tested by FinecareTM. Results and conclusions: FinecareTM showed 100% specificity, as none of the pre-pandemic samples tested positive. Equivalent FinecareTM results were observed among the samples taken from fingerstick or plasma (Pearson correlation r = 0.9, p < 0.0001), suggesting that fingerstick samples are sufficient to quantitate the S-RBD BAU/mL. A moderate correlation was observed between FinecareTM and sVNT (r = 0.5, p < 0.0001), indicating that FinecareTM can be used for rapid prediction of the neutralizing antibody (nAb) post-vaccination. FinecareTM BAU results showed strong correlation with VIDAS®3 (r = 0.6, p < 0.0001) and moderate correlation with VITROS® (r = 0.5, p < 0.0001) and CL-900i® (r = 0.4, p < 0.0001), suggesting that FinecareTM can be used as a surrogate for the advanced automated assays to measure S-RBD BAU/mL.This work was made possible by grant number UREP28-173-3-057 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors
GIZA 11 AND GIZA 12; TWO NEW FLAX DUAL PURPOSE TYPE VARIETIES
Sixteen flax genotypes {13 promising lines and 3 check varieties viz., Giza 8 (oil type), Sakha 1 (dual purpose type) and Sakha 3 (fiber type)} were evaluated for straw, seed, oil yields and their related traits under twelve different environments; four locations (Sakha, Etay El-Baroud, Ismailia and Giza Exp. Stations through three successive seasons (2011/12, 2012/13 and 2013/14). These materials were evaluated in a randomized complete blocks design with three replications at the twelve above-mentioned environments. The analysis of variance revealed highly significant differences among genotypes (G), environments (E) and G x E interaction for all studied traits except straw weight per plant, indicating a wide range of variation among genotypes, environments and these genotypes exhibited differential response to environmental conditions. The significant variance due to residual for all characters except both straw weight per plant and oil yield per fad indicated that genotypes differed with respect to their stability suggesting that prediction would be difficult, which means that mean performance alone would not be appropriate. Interaction component of variance (σ2ge) was less than the genotypic variance (σ2g) for all characters, indicating that genotypes differ in their genetic potential for these traits. This was reflected in high heritability and low discrepancy between phenotypic (PCV) and genotypic (GCV) coefficients of variability values for these traits indicating the possibility of using each of long fiber percentage, plant height and technical stem length as selection indices for improving straw weight per plant, as well as, using 1000-seed weight and capsules number per plant as selection indices for improving seed weight per plant. Yield stability (YSi) statistic indicated that S.541-C/3 and S.541-D/10 gave high mean performance and stability for straw, fiber, seed and oil yields per fad in addition to oil percentage, capsules number per plant and 1000-seed weight. Therefore, the two genotypes well be released under the name Giza 11 and Giza 12, respectively. These newly released varieties are of dual purpose type for straw, fiber, seed and oil yield. They may replace the low yielding cultivars Giza 8, Sakha 1 and Sakha 3
The Usability of E-learning Platforms in Higher Education: A Systematic Mapping Study
The use of e-learning in higher education has increased significantly in recent years, which has led to several studies being conducted to investigate the usability of the platforms that support it. A variety of different usability evaluation methods and attributes have been used, and it has therefore become important to start reviewing this work in a systematic way to determine how the field has developed in the last 15 years. This paper describes a systematic mapping study that performed searches on five electronic libraries to identify usability issues and methods that have been used to evaluate e-learning platforms. Sixty-one papers were selected and analysed, with the majority of studies using a simple research design reliant on questionnaires. The usability attributes measured were mostly related to effectiveness, satisfaction, efficiency, and perceived ease of use. Furthermore, several research gaps have been identified and recommendations have been made for further work in the area of the usability of online learning
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