14 research outputs found

    Uticaj supstituenata na IR, 1H- i 13C-NMR spektralne podatke N-(supstituisanih fenil)-2-cijanoacetamida - korelaciona analiza

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    Linear free energy relationships (LFER) were applied to the IR, H-1- and C-13-NMR spectral data of N-(substituted phenyl)-2-cyanoacetamides. A variety of substituents were employed for phenyl substitution and fairly good correlations were obtained using the simple Hammett and the Hammett-Taft dual substituent parameter equations. The correlation results of the substituent induced C-13-NMR chemical shifts (SCS) of the Cl, C=O and N-H atom indicated different sensitivity with respect to electronic substituent effects. A better correlation of the SCSc=O with a combination of electrophllic and nucleophilic substituent constants indicated a significant contribution of extended resonance interaction (pi-delocalization) within the pi(1)-unit. The conformations of the investigated compounds were studied using the OFT B3LYP/6-311G** method and, together with the results of C-13-NMR and IR spectroscopic studies, a better insight into the influence of such a structure on the transmission of electronic substituent effects was obtained.Principi linearnih korelacija slobodnih energija (LFER) su primenjeni na IR, 1H- i 13C-NMR spektralne podatke N-(supstituisanih fenil)-2-cijanoacetamida. Pri sintezi N-(supstituisanih fenil)-2-cijanoacetamida izvršen je zadovoljavajući izbor supstituenata u pogledu elektronskih svojstava kako bi se adekvatno sagledao uticaj elektronskih efekata supstituenata na pomeranja u IR, 1H- i 13C-NMR spektralnim podacima. Primenom proste Hametove jednačine dobijene su zadovoljavajuće korelacije. Na osnovu korelacionih rezultata uočen je primaran uticaj elektronskih efekata na SCS (supstituentom indukovana hemijska pomeranja) vrednosti N-H vodonika, C1 i C=O ugljenika ispitivanih jedinjenja. Korelacioni rezultati za C=O ugljenik se značajno popravljaju ako se koristi kombinacija Ϭ+ i Ϭ- konstanti supstituenata, takozvane elektrofilne i nukleofilne konstante supstituenata, što ukazuje na postojanje značajne proširene rezonancione interakcije supstituenata i elektronske gustine karbonilne grupe. Vrednosti konstanti proporcionalnosti pF i pR za sve atome, ukazuju na približno isti doprinos efekta polja i rezonancionog efekta supstituenata. Efekat polja je nešto izraženji na N-H vodoniku, i za sve atome pokazuje značajne razlike u odnosu na njihov položaj u molekulskoj strukturi ispitivanih jedinjenja. Uticaj efekata supstituenata na IR vibracije istezanja N-H (simetrične i antisimetrične), C=O i CN veze je prevashodno elektronske prirode što se može zaključiti na osnovu dobrih korelacija dobijenih primenom Hametove jednačine i Ϭ parametara supstituenata. Osim toga izvršena je optimizacija geometrije ispitivanih jedinjenja primenom DFT B3LYP/ 6-311G**metode, pri čemu je nađeno da je trans-izomer nešto stabilnji, izuzev u slučaju jedinjenja 3. Supstituisana fenil-grupa i amidna grupa, kod trans-izomera, su približno koplanarne, dok se kod cis- izomera uočava značajna devijacija koja je značajno određena elektronskim efektima prisutnog supstituenta. Takođe je ispitivan položaj cis/trans ravnoteže u ugjen-tetrahloridu, i na osnovu rezultata FT/R analize, kada je prisutan H, CH3, OCH3, Br, i COOH supstituent, nađeno je da je cis izomer u velikom višku, a za ostala jedinjenja utvrđeno je postojanje ravnoteže cis- i trans-izomera

    Deliverable 3.4: National Development Plans for Data Services in Non-CESSDA Member Countries in the ERA

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    This deliverable contains the second output of task 3.3 – national development plans for establishing data services in the social sciences in non-CESSDA member countries in Europe. The goal of task 3.3 of CESSDA SaW was to draw up individual national development plans for aspiring CESSDA Service Providers. In total, NDPs have been developed in 13 countries. Nine NDPs are included in this deliverable, while four are still pending approval from national authorities and/or local potential host institutions

    Renal cancer and Wegener's granulomatosis: a case report

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    Wegener's granulomatosis (WG) is a systemic disorder characterized by necrotizing vasculitis involving the respiratory tract, and in most cases, the kidneys. The most common manifestation of WG in the kidneys is segmental necrotizing glomerulonephritis. The presence of a renal mass as a manifestation of WG is rare. We report a patient with WG in whom a CT scan revealed an infiltrating mass in the lower portion of the left kidney. After surgical exploration, we performed an open radical nephrectomy. Histopathology showed clear cell type renal cell carcinoma (RCC). RCC associated with WG has been reported in only a few cases, and in most of them, the diseases started simultaneously, suggesting common pathogenetic pathways. Long-term immunosuppressive treatment is a known risk factor in the development of malignancies, so occurrence of RCC in WG has been proposed as a side effect of cyclophosphamide treatment. Furthermore, it is important to make a differential diagnosis between RCC and pseudotumors in WG as they cannot be distinguished solely on basis of imaging findings. Due to the higher risk of urologic malignancies, more frequent checkups and screening of WG patients should be considered

    A Predictive Model of Pandemic Disaster Fear Caused by Coronavirus (COVID-19): Implications for Decision-Makers

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    This paper presents quantitative research results regarding a predictive model of pandemic disaster fear caused by the coronavirus disease (COVİD-19). The aim of this paper was to establish the level and impact of certain demographic and socioeconomic characteristics on pandemic disaster fear caused by the coronavirus (COVID-19). The research was conducted using a questionnaire that was provided and then collected online for 1226 respondents during May 2021. A closed, five-point Likert scale was used to create the structured questionnaire. The first section of the questionnaire included research questions about the participants’ socioeconomic and demographic characteristics, while the second section included issue questions about fear caused by COVID-19. The results of multivariate regression analyses showed the most important predictor for fear of COVID-19 to be gender, followed by age and education level. Furthermore, the results of t-tests showed statistically significant differences between men and women in terms of different aspects of pandemic disaster fear caused by the coronavirus disease. Our results have several significant public health implications. Women who were more educated and knowledgeable, married, and older, reported a greater fear of the outbreak at various levels. Decision-makers can use these findings to identify better strategic opportunities for pandemic disaster risk management

    Implementation of image analysis on thermal shock and cavitation resistance testing of refractory concrete

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    This paper presents monitoring of changes during thermal shock and cavitation testing for low cement concrete that was synthesized and sintered at 1600 degrees C for 3h. Water quench test was applied as an experimental method for thermal stability testing. Image analysis of the samples showed some level of deterioration at the surface and inside the samples before water quench test. During the testing, the level of samples destruction was increasing. Damages inside the samples and at the surface during the water quench test were correlated to the number of quench experiments. Models based on the damage level of both the surface and inside the bulk were proposed for calculation of the strength degradation. Cavitation damages of the samples were induced by the modified vibratory cavitation set-up. Mass loss and surface erosion were determined during the experiment. The results indicated excellent thermal shock behavior and resistance to cavitation erosion. (c) 2010 Elsevier Ltd. All rights reserved

    Age as a prognostic factor in skin melanoma

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    The aim of this study was to establish whether older patients with skin melanoma (in an analyzed group of 189 patients treated at the Institute for Oncology and Radiology of Serbia from 2004 to 2008), have worse survival compared to younger patients. In 100 men and 89 women with an average age of 58.9 years, the following parameters were observed and statistically analyzed in SPSS: gender, age, localization, tumor thickness, ulceration, lymphonodal status and invasion level. In the four age subgroups - quartiles, the best survival was shown in patients <50 years (85.7%), and the worst in patients >70 years (76.1%). Patients without ulcerations, with negative lymph nodes, thin melanomas and Clark levels I and II had significantly better survival outcomes. Although the results showed no statistical significance of age as a prognostic factor in the survival of patients with skin melanoma, further research on a larger number of patients is warranted
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