1,721,026 research outputs found
Structural characterization, cytotoxic and enzyme inhibitory profile of a novel triazole-linked ferrocene hybrid of 18β-glycyrrhetinic acid
No full text18β-Glycyrrhetinic acid (GA) is a pentacyclic triterpene which was obtained from the roots of Glycyrrhiza glabra known for its diverse pharmaceutical applications. The primary aim of this study is to enhance the pharmaceutical properties of GA by modifying it with a 1,2,3-triazole-functionalized ferrocene moiety. The hybrid compound 3 was synthesized by amide functionalization of GA at the C-30 position with ferrocene, linked via a 1,4-disubstituted 1,2,3-triazole bridge. Additionally, the C-3 hydroxyl group of GA was converted into an acetyl ester. The hybrid compound 3 was characterized using FT-IR, NMR (1H and 13C) and HR-MS. The aim of the modification was to enhance the cytotoxic and enzyme inhibitory effects of GA. 1,2,3,-Triazole substituted ferrocene (1), C-3 acetylated GA and the hybrid compound 3 were tested on A549, MCF-7, HCT-116, and PC-3 cancer cell lines. MCF-7 and HCT-116 cells showed the highest sensitivity to the compounds. Compound 3 showed more cytotoxicity than both GA and compound 1 with IC50 values of 23.97 and 50 µM in MCF-7 and HCT-116 cells, respectively. Morphological analysis indicated that compound 3 induced apoptotic cell death. In addition, the inhibitory effect of compounds on carbonic anhydrase I-II isoenzymes (hCAI-II), acetylcholinesterase/butyrylcholinesterase (AChE/BChE) enzymes, and α-glucosidase was tested. According to the results, compound 3, exhibited the strongest inhibitory properties for all enzymes tested with IC50 values of 0.0323, 0.3058, 0.0078, 0.0090 and 0.0120 µM, respectively. Molecular docking studies were performed to investigate the ligand-target protein interactions. Incorporating an organometallic sandwich-like compound ferrocene into GA via a 1,2,3-triazole bridge appears to be an effective strategy for modifying and enhancing its bioactivity
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Anti‐proliferative and Apoptotic Effects of Coordination Compounds of Zinc(II), Palladium(II), and Platinum(II) with Tridentate 4‐(6‐hydroxyphenyl)‐2,6‐di(thiazol‐2‐yl)pyridine
No full textBu tezin, veri tabanı üzerinden yayınlanma izni bulunmamaktadır. Yayınlanma izni olmayan tezlerin basılı kopyalarına Üniversite kütüphaneniz aracılığıyla (TÜBESS üzerinden) erişebilirsiniz.ÖZET ; ı Henüz onsekiz yıllık bir geçmişi olan sentez problemlerinden biri, ısı değiştirgeç ağ sentezidir. Hedeflenen bir sıcaklığa getirilmek istenen sıcak ve soğuk akımlar arasında ısı değişimini sağlayacak ısı değiştirgeç ağlarının optimum sentezi aranmaktadır. Amaç utilitelerin ve aygıtların yıllık maliyetlerini enaza indirebilmektir. Böyle bir problemin çok sayıda seçenek çözümü vardır. Bu konudaki yöntemler höristik, kombinasyonel ve termodinomik yaklaşım olarak üç grupta toplanabilir. Bu çalışmada kombinasyonel yöntem grubuna giren"Sentez Ağacı Algoriması" ve termodinamik yaklaşımla çözüm getiren "Pinch Noktası Yöntemi" incelenmiş ve örnek problem çözümleriyle etkinlikleri araştırılmıştır. Sentez Ağacı Algoritması IBM-PC mikrobi lgisayarında, Basic proglamlama dilinde hazırlanan bir programla tümüyle bilgisayardan sonuç alınabilecek düzleme getirilmiştir. Aynı şekilde hazırlanan bir paket programla da Pinch noktası yöntemine önemli bir bilgisayar desteği getirilmiştir, fakat yine de Pinch noktası yönteminde kullanıcıya bırakılmış kararlar ve işlemler mevcuttur. Bu çalışmada bu iki yöntemin birbirlerine olan üstünlükleri incelenmektedir. Pinch noktası yöntemiyle, mevcut bir prosesin yeniden değerlendirilmesi ve daha iyi koşullara getirilmesi işlemi olarak tanımlanabilen retrofit işlemi yapılabilir. Ham petrol ısıtma prosesinin değerdirilmesi bu isleme örnek olarak getirilmektedir. Sentez ağacı algoritması bilgisayar programı kullanılarak 4,5,6,7 ve 10 akımdan oluşan problemler çözümlenmiştir. Akım sayısı arttıkça sentez seçenek sayısı çok arttığından (rafine edilmemiş bir problemin N=(NH*NC) olası birim ürettiği düşünülürse bu artısın nedeni daha kolay görülebilir) doğru orantılı olarak bilgisayar zamanı da artmaktadır. Bu nedenle akım ayrılmasına yani döngülere izin veren pinch noktası yöntemi kullanılarak aynı örnek problemlerden çözüm biçimleri sunulmuştur. Heriki yöntem de algoritmik düzleme getirildiğinden aynı biçimde, çok farklı problemler çözümlenebilir. Bu çalışma kapsamı içine bu örneklerden birkaçı alınmıştır, ilerki çalışmalarda, su anda programa veri olarak girilen değerlerin (aygıt özellikleri) program içinde hesaplanması düşünülmektedir. Pinch noktası yönteminin tamamiyle bilgisayarda çözümü (bilgisayarların grafik özelliklerinden yararlanarak) üzerinde durulacaktır. Bir diğer hedef ise su anda yazılı olan paketleri geliştirmek ve daha etkin duruma getirmektir..ii-SUMMARY Chemical Engineering Process Synthesis has a past of nearly two decades, and one of the most important problems in this field is the optimal heat exchanger network synthesis. The task is to verify certain matches between cold and hot process streams in a heat exchanger network so that the use of utilities and the heat transfer area will be minimum.Such a problem has many alternative solutions. Methods for such a synthesis problem can be considered into three groups: heuristic, combinational, and thermodynamical methods. In this work the "Tree Search Method " and "The Pinch Point Method" were taken into consideration and their ef f ectivities were studied and illustrated. The "tree search" algorithm was programmed in BASiC on an IBM-PC microcomputer. The "pinch point" algorithm was programmed but needs intervention of the engineer for certain decisions. By making use of the "pinch point" method, it is possible to develope an algorithm which retrofits an existing process. This approach was illustrated by The heating operation of the raw petroleum in the ALiAGA Refinery of TUPRAS. The computer program of the "tree search" algorithm was used to solve systems of 4,5,6,7, and 10 process streams. The greater the number of streams the greater the CPU time on a computer needed to solve the problems. So considering the number of alternatives to be, N=(NH*NC) !,it is easy to see how much time will be required when the system is considerably large. For such reasons, the "pinch point" method which is suitable for stream splitting and recycling conditions was used to illustrate the differences. The programs need data about the equipment. It is planned to add the required design calculations of the heat transfer equipment and graphic fascilities for decision-making to the computer program in the future work. - 111
Tr-KIT downstream regulation by YY1 and NFYA transcription factors knockdown in prostate cancer cells
No full textBackgroundProstate cancer is a common and deadly cancer among men and has been the subject of many patients in its diagnosis and treatment. Imatinib, a tyrosine kinase inhibitor, can slow tumor formation by targeting c-KIT, an oncogenic receptor tyrosine kinase protein over-expressed in PCa cases. However, Imatinib has no effect on tr-KIT, a truncated form of c-KIT, which is over-expressed in PCa and is associated with neoplastic transformation. In this study, it is aimed to answer whether the anti-proliferative efficacy of Imatinib on PCa cells could be enhanced by inhibition of tr-KIT specific transcription factors.Methods and ResultsFor this purpose, gene expression analysis and cell viability assays were performed in LNCaP prostate cancer cells to investigate the effects of inhibition of transcription factors controlling tr-KIT expression (YY1 and NFYA) in combination with Imatinib administration. As a result, YY1 and NFYA were identified as tr-KIT-specific transcription factors and found that their knockdown increased the effectiveness of Imatinib mesylate treatment on LNCaP cells. The study also analyzed the gene expression changes of c-KIT, FYN, PLC gamma 1, and SAM68 genes and found that SAM68 expression decreased with NFYA and YY1 knockdown, suggesting the existence of other unknown mediators in the tr-KIT pathway.ConclusionsAll in all, this study demonstrates that tr-KIT may be a potential pharmacological target for prostate cancer treatment and that inhibition of the transcription factors YY1 and NFYA may enhance the efficacy of Imatinib. SAM68 was found to be the most affected protein by the treatments, guiding future research
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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