Siga este link para ver outros tipos de publicações sobre o tema: Chemist activity.
Artigos de revistas sobre o tema "Chemist activity"
Crie uma referência precisa em APA, MLA, Chicago, Harvard, e outros estilos
Veja os 50 melhores artigos de revistas para estudos sobre o assunto "Chemist activity".
Ao lado de cada fonte na lista de referências, há um botão "Adicionar à bibliografia". Clique e geraremos automaticamente a citação bibliográfica do trabalho escolhido no estilo de citação de que você precisa: APA, MLA, Harvard, Chicago, Vancouver, etc.
Você também pode baixar o texto completo da publicação científica em formato .pdf e ler o resumo do trabalho online se estiver presente nos metadados.
Veja os artigos de revistas das mais diversas áreas científicas e compile uma bibliografia correta.
1
Howder, Collin R., Kyle D. Groen, and Thomas S. Kuntzleman. "JCEClassroom Activity #107. And the Oscar Goes to...A Chemist!" Journal of Chemical Education 87, no. 10 (2010): 1060–61. http://dx.doi.org/10.1021/ed900013z.
Texto completo da fonte
2
Efimova, I. "Boris Belousov, Talented Scientific Chemist Dedication Page of Biography." Medical Radiology and radiation safety 66, no. 6 (2021): 116–18. http://dx.doi.org/10.12737/1024-6177-2021-66-6-116-118.
Texto completo da fonteResumo:
The article contains material on scientific activity of the famous scientific chemist B. Belousov, the head of the laboratory of the Institute of Biophysics of the Ministry of health of the USSR, the creator of an effective anti-radiation drug, the author of the invention of the vibrational reaction Belousov-Jabotinsky.
3
Chojecki, Mirosław. "NOW-a w karnawale." Wolność i Solidarność 10 (2017): 50–61. http://dx.doi.org/10.4467/25434942ws.17.003.13116.
Texto completo da fonteResumo:
NOWa Publishing House during the "Solidarity carnival" period in 1980-1981 NOWA was an independent and underground publishing house founded by the democratic opposition in the 1970s. The following article is a presentation of Mirosław Chojecki memories. This chemist, employed at the Institute for Nuclear Research, was also a co-worker of the Workers' Defense Committee and one of the most active member of the NOWa publishing house. Article refers especially to the history of his activity during the “Solidarity carnival” period in 1980-1981.
4
Chojecki, Mirosław. "NOW-a w karnawale." Wolność i Solidarność 10 (2017): 50–61. http://dx.doi.org/10.4467/25434942ws.17.003.13116.
Texto completo da fonteResumo:
NOWa Publishing House during the "Solidarity carnival" period in 1980-1981 NOWA was an independent and underground publishing house founded by the democratic opposition in the 1970s. The following article is a presentation of Mirosław Chojecki memories. This chemist, employed at the Institute for Nuclear Research, was also a co-worker of the Workers' Defense Committee and one of the most active member of the NOWa publishing house. Article refers especially to the history of his activity during the “Solidarity carnival” period in 1980-1981.
5
Litterman, Nadia, Christopher Lipinski, and Sean Ekins. "Small molecules with antiviral activity against the Ebola virus." F1000Research 4 (February 9, 2015): 38. http://dx.doi.org/10.12688/f1000research.6120.1.
Texto completo da fonteResumo:
The recent outbreak of the Ebola virus in West Africa has highlighted the clear shortage of broad-spectrum antiviral drugs for emerging viruses. There are numerous FDA approved drugs and other small molecules described in the literature that could be further evaluated for their potential as antiviral compounds. These molecules are in addition to the few new antivirals that have been tested in Ebola patients but were not originally developed against the Ebola virus, and may play an important role as we await an effective vaccine. The balance between using FDA approved drugs versus novel antivirals with minimal safety and no efficacy data in humans should be considered. We have evaluated 55 molecules from the perspective of an experienced medicinal chemist as well as using simple molecular properties and have highlighted 16 compounds that have desirable qualities as well as those that may be less desirable. In addition we propose that a collaborative database for sharing such published and novel information on small molecules is needed for the research community studying the Ebola virus.
6
Ramesh, Muthusamy, and Arunachalam Muthuraman. "Quantitative Structure-Activity Relationship (QSAR) Studies for the Inhibition of MAOs." Combinatorial Chemistry & High Throughput Screening 23, no. 9 (2020): 887–97. http://dx.doi.org/10.2174/1386207323666200324173231.
Texto completo da fonteResumo:
Monoamine oxidases are the crucial drug targets for the treatment of neurodegenerative disorders like depression, Parkinson’s disease, and Alzheimer’s disease. The enzymes catalyze the oxidative deamination of several monoamine containing neurotransmitters, i.e. serotonin (5-HT), melatonin, epinephrine, norepinephrine, phenylethylamine, benzylamine, dopamine, tyramine, etc. The oxidative reaction of monoamine oxidases results in the production of hydrogen peroxide that leads to the neurodegeneration process. Therefore, the inhibition of monoamine oxidases has shown a profound effect against neurodegenerative diseases. At present, the design and development of newer lead molecules for the inhibition of monoamine oxidases are under intensive research in the field of medicinal chemistry. Recently, the advancement in QSAR methodologies has shown considerable interest in the development of monoamine oxidase inhibitors. The present review describes the development of QSAR methodologies, and their role in the design of newer monoamine oxidase inhibitors. It will assist the medicinal chemist in the identification of selective and potent monoamine oxidase inhibitors from various chemical scaffolds.
7
Kilah, Nathan L., and Eric Meggers. "Sixty Years Young: The Diverse Biological Activities of Metal Polypyridyl Complexes Pioneered by Francis P. Dwyer." Australian Journal of Chemistry 65, no. 9 (2012): 1325. http://dx.doi.org/10.1071/ch12275.
Texto completo da fonteResumo:
Sixty years ago, the Australian chemist Francis P. Dwyer pioneered the use of ruthenium polypyridyl complexes as biologically active compounds. These chemically inert and configurationally stable complexes revealed an astonishing range of interesting biological activities, such as the inhibition of the enzyme acetylcholinesterase, anti-cancer activity in vivo, and bacteriostatic/bacteriocidal action. This review commemorates the sixtieth anniversary of Dwyer and co-workers’ landmark 1952 publication, summarises their broader achievements in biological inorganic chemistry, and discusses the contribution of this work to the development of modern biological and medicinal inorganic chemistry.
8
Dearden, John C. "The History and Development of Quantitative Structure-Activity Relationships (QSARs)." International Journal of Quantitative Structure-Property Relationships 2, no. 2 (2017): 36–46. http://dx.doi.org/10.4018/ijqspr.2017070104.
Texto completo da fonteResumo:
Following the publication of the history and development of QSAR, it became apparent that a number of matters had not been covered. This addendum is an attempt to rectify that. A very early approach (ca. 60 B.C.) by Lucretius shows that he understood how molecular size and complexity affect liquid viscosity. Comments by Kant (1724-1804) emphasized the necessity of mathematics in science. A claim that the work of von Bibra and Harless in 1847 pre-dated that of Overton and H.H. Meyer is shown not to be correct. K.H. Meyer and Gottlieb-Billroth published in 1920 what is probably the first QSAR equation. Brown, who with his co-author Fraser is credited with the first definitive recognition in 1868-9 that biological activity is a function of molecular structure, is often cited as Crum Brown; in fact, Crum was his second given name. The QSAR work of the Soviet chemist N.V. Lazarev in the 1940s was far ahead of his time, showing numerous correlations of biological activities and physicochemical properties with molecular descriptors. The subject of inverse QSAR is discussed.
9
Hodgson, Geoffrey M., and Michael Polanyi. "Editorial introduction to ‘Collectivist planning’ by Michael Polanyi (1940)." Journal of Institutional Economics 15, no. 6 (2019): 1055–74. http://dx.doi.org/10.1017/s1744137419000377.
Texto completo da fonteResumo:
AbstractAfter an esteemed academic career as a chemist, Michael Polanyi switched to the social sciences and made significant contributions to our understanding of the nature and role of knowledge in society. Polanyi's argument concerning knowledge led him to emphasise the vital importance of decentralised mechanisms of adjustment and coordination, including markets. His article ‘Collectivist Planning’ (1940) enters into debates about the possibility (or otherwise) of centrally planning scientific and economic activity. This early article also foreshadows post-war debates within the Mont Pèlerin Socierty (formed in 1947) concerning the economic role of the state and the future of liberalism.
10
M.K.M, ABDUL LATHIFF, SURESH R, and SENTHAMARAI R. "A REVIEW ON ANTICANCER ACTIVITIES OF NOVEL DIHYDRO PYRIMIDINONES / THIONES DERIVATIVES." YMER Digital 21, no. 03 (2022): 460–72. http://dx.doi.org/10.37896/ymer21.03/47.
Texto completo da fonteResumo:
Dihydropyrimidinones and thiones are a significant class of organic as well as heterocyclic compounds synthesized by cyclo condensation reaction, called Biginelli reaction that was reported for the first time by Italian chemist Pietro Biginelli in 1893. The synthesis of dihydropyrimidinones and thiones involve one pot multicomponent reaction (MCR) of various aldehydes, β- ketoester and urea or thiourea. Now, the dihydropyrimidinones and thiones have emerged as one of the most advantaged medicinal pharmacophores as they appear as an important structural part in many naturally occurring and synthetically prepared medicinal drugs. It possesses wide spectrum of biological activities like antitubercular, Anti-malarial, anticancer, anti-HIV activity, analgesic, antiepileptic, CNS activity, anti-inflammatory, calcium and potassium channel blocker [2], antihypertensive agents [3], α-la-antagonist [4], antioxidants [6] and neuropeptide Y (NPY) antagonists.[7]
11
Sharma, Praveen K., Andleeb Amin, and M. Kumar. "A Review: Medicinally Important Nitrogen Sulphur Containing Heterocycles." Open Medicinal Chemistry Journal 14, no. 1 (2020): 49–64. http://dx.doi.org/10.2174/1874104502014010049.
Texto completo da fonteResumo:
Nitrogen sulphur containing heterocycles have specific properties due to which they can be used as a potential material in a different type of industries such as medicinal/pharmaceutical, paint, packing and textile, required for various chemical, physical operations and their use as products. Especially dyes, paint, agrochemicals, medicine, etc. make them more significant. In present days, Nitrogen-Sulfur heterocycles are repeatedly attracting the interest of chemists due to their exceptional bioactive behavior. The present study is a review of the work carried out by a chemist in the discovery of new, effective, medicinally important heterocyclic compounds. The present review basically focused on nitrogen-sulfur heterocycles of potential therapeutic interest, especially with thiazole, thiazine, pyrimidine, morpholine and piperazine heterosystems, benzothiazines, pyrazole-benzothiazines, morpholine-benzothiazines, piperazine-benzothiazines and pyrimidine-benzothiazoles, mainly due to their unique structural features, which enable them to exhibit a number of biological and pharmacological activities. Due to a novel mode of action, a broad spectrum of activity, lesser toxicity towards mammalian cells, and suitable profiles towards humans have triggered the use of Nitrogen Sulphur containing heterocycles in designing and synthesizing their derivatives with better properties. The overall objective of the review is to discuss the importance of novel biodynamic structurally diverse heterocycles of potential therapeutic interest: pyrimidine, morpholine, piperazine, pyrozole, benothiazoles, pyrimidobenzothiazoles, 4H-1,4-benzothiazines, pyrazolyl-benzothiazines, morpholinyl-benzothiazines and piperazinylbenzothiazines in order to have access to important commercial molecules for the search of better future.
12
Moeed, Swehra. "Activity-based Learning and Development of High Mental Abilities an Intention of Intermediate Level Chemistry Syllabus." International Journal of Emerging Issues in Early Childhood Education 1, no. 2 (2020): 115–26. http://dx.doi.org/10.31098/ijeiece.v1i2.55.
Texto completo da fonteResumo:
Course content is a hub of educational activities. The method of teaching and assessment proceduremore or less rely on the nature of syllabus. Being core of educational activities great importance isgiven to course content. This study was conducted to investigate the opinion of teachers concerningexisting syllabus of intermediate level chemistry subject. The data was gathered throughquestionnaire based on 5 point Likert scale items. Sixty three teachers of chemist ry subject wereworking at Government Degree Colleges (GDCs) and Government Higher Secondary Schools(GHSSs) of district Peshawar. Among sixty three fifty seven teachers were selected randomly assample of study. The collected data prevail that the implemented syllabus is mostly based on theory,hence in such circumstance the national aim to produce skill generation as per demand of marketseem impossible. The condition of practical work and hand on activities is dispiriting in governmenteducational institutes. The psychological and social need of students has been ignored whiledesigning the syllabus. The text book is a mean of imparting pre-set information, it seems failed toprovide valuable engaging activities.
13
Ergene, Cansu, and Edmund F. Palermo. "Antimicrobial Synthetic Polymers: An Update on Structure-Activity Relationships." Current Pharmaceutical Design 24, no. 8 (2018): 855–65. http://dx.doi.org/10.2174/1381612824666180213140732.
Texto completo da fonteResumo:
The rising incidence of antibiotic-resistant infections, combined with a declining number of new antibiotic drug approvals, has generated an alarming therapeutic gap that critically undermines public health. Host Defense Peptides (HDPs), sometimes referred to as “Nature’s Antibiotics”, are short chain, amphiphilic and cationic peptide sequences found in all multicellular organisms as part of their innate immunity. While there is a vast diversity in terms of HDP sequence and secondary structure, they all seem to share physiochemical characteristics that can be appropriated for macromolecular design by the synthetic polymer chemist. Over the past decade, remarkable progress has been made in the design and synthesis of polymer-based materials that effectively mimic HDP action – broad-spectrum antibacterial potency, rapid bactericidal kinetics, and minimal toxicity to human cells – while offering the additional benefits of low cost, high scalability, and lower propensity to induce resistance, relative to their peptide-based counterparts. A broad range of different macromolecular structures and architectures have been explored in this design space, including polynorbornenes, poly(meth)acrylates, poly(meth)acrylamides, nylon-2 polymers, and polycarbonates, to name a just few. Across all of these diverse chemical categories, the key determinants of antibacterial and hemolytic activity are the same as in HDPs: net cationic charge at neutral pH, well-balanced facial amphiphilicity, and the molecular weight of the compounds. In this review, we focus in particular on recent progress in the polymethacrylate category first pioneered by Kuroda and DeGrado and later modified, expanded upon and rigorously optimized by Kuroda’s and many other groups. Key findings and future challenges will be highlighted.
14
Stepanov, Nano. "Louis Pasteur (1822 – 1895) – The Chemist, on the Occasion of the 200-th Anniversary of His Birth." Natural Science and Advanced Technology Education 31, no. 3 (2022): 293–317. http://dx.doi.org/10.53656/nat2022-3.07.
Texto completo da fonteResumo:
The article is dedicated to the 200-year anniversary of the great Louis Pasteur and aims to represent his work focusing on his less famous contributions as a chemist. By examining his accomplishments in the historical context of chemistry’s development – isomerism (between Berzelius and Van’t Hoff) and theory of fermentation (between Liebig and Berthelot). Based on his research on optically active substances (mainly tartaric acid and its salts) he distinguishes optical activity caused by crystal structure and molecular asymmetry, hypothesizes that the way atoms are positioned in a molecule is the cause for optical activity, defining a new form of isomerism thus paving the way for stereochemistry. The later scientific achievements of Pasteur are related to him entering the world of microorganisms – fermentation, disproving the theory of spontaneous generation, clarifying the origin and prevention of infectious diseases. It is emphasized that he is a scientist who takes his work out of the laboratory and ‘into the world’: examining the diseases of the silk worm, difficulties in brewing, wine and vinegar production. He communicates with people affected by the problem, exchanges knowledge and experience with them, offers advice, includes them in his search for solutions. Generally describing his work as a physicochemist, biochemist, microbiologist, immunologist and his personality with emphasis on his morality as a scientist. He is a patriot, citizen, humanist and a true benefactor of humanity.
15
Campbell, Duncan J., Juerg Nussberger, Michael Stowasser, et al. "Activity Assays and Immunoassays for Plasma Renin and Prorenin: Information Provided and Precautions Necessary for Accurate Measurement." Clinical Chemistry 55, no. 5 (2009): 867–77. http://dx.doi.org/10.1373/clinchem.2008.118000.
Texto completo da fonteResumo:
AbstractBackground: Measurement of plasma renin is important for the clinical assessment of hypertensive patients. The most common methods for measuring plasma renin are the plasma renin activity (PRA) assay and the renin immunoassay. The clinical application of renin inhibitor therapy has thrown into focus the differences in information provided by activity assays and immunoassays for renin and prorenin measurement and has drawn attention to the need for precautions to ensure their accurate measurement.Content: Renin activity assays and immunoassays provide related but different information. Whereas activity assays measure only active renin, immunoassays measure both active and inhibited renin. Particular care must be taken in the collection and processing of blood samples and in the performance of these assays to avoid errors in renin measurement. Both activity assays and immunoassays are susceptible to renin overestimation due to prorenin activation. In addition, activity assays performed with peptidase inhibitors may overestimate the degree of inhibition of PRA by renin inhibitor therapy. Moreover, immunoassays may overestimate the reactive increase in plasma renin concentration in response to renin inhibitor therapy, owing to the inhibitor promoting conversion of prorenin to an open conformation that is recognized by renin immunoassays.Conclusions: The successful application of renin assays to patient care requires that the clinician and the clinical chemist understand the information provided by these assays and of the precautions necessary to ensure their accuracy.
16
Shul'pin, Georgiy B. "C–H functionalization: thoroughly tuning ligands at a metal ion, a chemist can greatly enhance catalyst's activity and selectivity." Dalton Transactions 42, no. 36 (2013): 12794. http://dx.doi.org/10.1039/c3dt51004b.
Texto completo da fonte
17
Debue-Barazer, Christine. "Les implications scientifiques et industrielles du succès de la Stovaïne®. Ernest Fourneau (1872–1949) et la chimie des médicaments en France." Gesnerus 64, no. 1-2 (2007): 24–53. http://dx.doi.org/10.1163/22977953-0640102002.
Texto completo da fonteResumo:
The synthetic local anaesthetic Stovaïne® was commercialised in France in 1904. Its inventor, Ernest Fourneau, began his career as a pharmaceutical chemist in organic chemistry laboratories in Germany, where from 1899 to 1901 he discovered how basic research could benefit from the modern chemistry theories which had developed in Germany starting in the 1860s. Using the complex structure of cocaine, he invented an original molecule, with comparable activity, but less toxic. The knowledge and the know-how which he acquired in Germany nourished his reflection in the field of the chemistry of the relationships between structure and activity, and led him to the development of Stovaïne®. Emile Roux, Director of the Pasteur Institute in Paris,was interested in his work and invited him to head the first French therapeutic chemistry laboratory, in which research on medicinal chemistry was organised scientifically. The industrial development of new medicines resulting from the Pasteur Institute’s therapeutic chemistry laboratory was supported by the Etablissements Poulenc frères, France thus gaining international reputation in the domain of pharmaceutical chemistry.
18
Caliński, Tadeusz. "Rozwój i osiągnięcia w biometrii polskiej." Przegląd Statystyczny. Statistical Review 2012, SI1 (2012): 47–52. http://dx.doi.org/10.59139/ps.2012.si1.2.
Texto completo da fonteResumo:
Biometry is a branch of science which deals with applications of mathematical and statistical methods to biological problems, particularly to the design and analysis of experiments. Two prominent scientists are considered as pioneers of biometry in Poland. An anthropologist, Jan Czekanowski (1882-1965), and a chemist, agricultural researcher and plant breeder, Edmund Załęski (1863-1932). One of Załęski’s followers was Stefan Barbacki, a scientist of great achievements in the development of agricultural research methodology and biometry. His activity contributed essentially to the formation of the Poznań school of mathematical statistics and biometry. The interest in biometry in other Polish scientific centers was initiated in a similar way. Particularly in Lublin, due to Mikołaj Olekiewicz and Wiktor Oktaba, in Warsaw, due to Jerzy Spława-Neyman and Zygmunt Nawrocki, and in Wrocław, due to Hugo Steinhaus and Julian Perkal (1913-1965).
19
Aminova, E. K., D. N. Bilalova, N. A. Kireeva, and M. A. Malikova. "STUDY OF THE DISCIPLINE "ANALYTICAL CHEMISTRY" IN ENGLISH AT A TECHNICAL UNIVERSITY." Bulletin USPTU Science education economy Series economy 4, no. 34 (2020): 119–23. http://dx.doi.org/10.17122/2541-8904-2020-4-34-119-123.
Texto completo da fonteResumo:
One of the most priority directions of development of the state University is its international activities. Paying great attention to the English language, technical University teachers achieve the following goals: to consolidate and develop business relations to improve the higher education system in the current conditions; to increase the authority of the University as a center of educational, scientific and research activities; to develop international cooperation of the University. Chemistry occupies one of the main places among the subjects studied at school. Chemistry is an interesting and entertaining science so many students decide to associate their future profession with this subject. Students studying in the specialty "Chemical technology", most often after graduation work in chemical laboratories, in the positions of laboratory chemist and analytical chemist. Therefore, it is important for them to study the discipline "Analytical chemistry" in more depth, including in English. Currently, one of the important roles in modern technical Universities is the study of English. A large number of foreign literature sources containing important information: methods of chemical analysis, modern scientific directions in the field of analytical chemistry indicate the need to study technical English. Therefore, undoubtedly, the provision of knowledge and foreign language proficiency of future specialists in the petrochemical industry is a necessary condition for professional training. In this regard, the problem of developing and implementing innovative methods of teaching English becomes urgent. The greatest effectiveness in language learning is achieved by combining traditional methods with modern technologies. And remote monitoring capabilities increase the interest and cognitive activity of students to study the subject. This article analyzes the effectiveness of the proposed method. It also describes the psychological and psychophysiological features of perception and memorization of information by students, offers a method of presenting lecture material and interacting with students, which is relevant today.
20
Nandal, Rimmy, Aakash Deep, Ishwar Singh, et al. "Synthesis of Metal Complexes of Primaquine and In-vitro Antimalarial Evaluation Against Plasmodium falciparum." Current Bioactive Compounds 15, no. 6 (2020): 631–36. http://dx.doi.org/10.2174/1573407214666180720124844.
Texto completo da fonteResumo:
Background: Resistance to malarial drugs represents a major obstacle in the treatment of disease, thereby increasing the need for more efficient drugs. The development of metal complexes offers the medicinal chemist an opportunity to expand the activity of drugs. For providing supportive therapy to the host to boost its immune system several new antimalarial drugs are being beneath research, but sufficient information on their efficacy is yet not available. Methods: In view of above, eight drug metal complexes (Ba (II), Ca (II), Zn (II), St (II), Hg (II), Fe (III), Cu (II), Ni (II) of Sulfamethoxazole (SMX) and Primaquine were synthesized and in-vitro evaluated for their antimalarial activity against malaria parasite Plasmodium falciparum by using fluorescence based assay. Result: The antimalarial activity of Nickel (EC50= 1.41µM) and Zinc (EC50=0.96µM) complexes have shown tremendous activity as compared to the standard drug Primaquine (EC50=0.07µM). The structures of all these newly synthesized derivatives were confirmed by spectral data (IR, 1H NMR, 13C NMR and Mass spectrometry). Conclusion: In conclusion, this study describes that the preparation and antimalarial evaluation of metal complexes of primaquine and sulphamethoxazole. Evaluation of their possible biological activities such as antimalarial activity was carried out and most of the synthesized compounds (Nickel and Zinc metal complexes) showed the good activity as compared to the standard drug primaquine. Therefore the compounds are appropriate candidates for more investigation and some more derivatives can be synthesized to get an imminent into the structure activity relationship of these compounds to be employed as biologically useful agents.
21
SIMÕES, ANA. "Textbooks, popular lectures and sermons: the quantum chemist Charles Alfred Coulson and the crafting of science." British Journal for the History of Science 37, no. 3 (2004): 299–342. http://dx.doi.org/10.1017/s0007087404005424.
Texto completo da fonteResumo:
In this paper I address C. A. Coulson's teaching activities, writing textbooks and delivering popular science lectures, as well as his popular lectures on religion and the ‘scientific’ sermons delivered in his capacity as a lay preacher of the Methodist Church. I will pay particular attention to his thoughts on science. His commitment to forging a way to reconcile science and religion was built upon a reflection on the aims and methods of science within the broader framework of science's role in post-Second World War society. By noting that Coulson valued chemistry, mathematics and science in general, as a kind of religious activity, I argue that he wrote masterful textbooks and delivered popular science lectures as lay sermons. These were activities which Coulson pursued energetically to build a community of science adepts and proselytes. And winning young, and indeed not so young, people to science meant teaching them one of the languages that could be used to reach God. In the same way, I extend my argument to his popular lectures on religion and his ‘scientific’ sermons and claim that they should be viewed as popular science lectures addressed to an audience that was often ignorant, or even suspicious, of science.
22
Sajida. Munadi. Th.AL-Suraify and Mohammed Abdul-Mounther Othman. "Synthesis and study of spectrally diagnosed heterocyclic compound." International Journal of Research in Pharmaceutical Sciences 11, SPL4 (2020): 2613–22. http://dx.doi.org/10.26452/ijrps.v11ispl4.4527.
Texto completo da fonteResumo:
In general terms, medicinal chemistry manages the revelation & plan of recent remedial synthetic concoctions & its uses as meds. Throughout the most recent couple of decades, mixes bearing heterocyclic cores have gotten considerably more consideration of the scientific expert, because of their expansive chemo remedial exercises, for example, calming, anthelmintic, hostile to tubercular, against parasitic & hostile to microbial exercises. Furthermore, Heterocycles & medicines are both interred related, the human is totally dependent on drugs & most of the drugs are derived from heterocyclic compounds. Hetero cycles & their derivatives have been excited regards chemist mainly due to broad-spectrum chemical & pharmacological activities. Most of the heterocyclic compounds are naturally occurs & playing the important role of metabolism regards cells of living. There has been a bigger count of pharmacologically attracted compounds of heterocyclic, several of which have been under continues clinical utilization. This paper presented a detailed study of synthesis which is spectrally detected Heterocyclic compounds, in results described the antibacterial activity of (e)-s-4-(is nicotinamide)-5-(phenoxymethyl)-4h-1, 2, 4-triazol-3-yl 3-(substituted phenyl) prop-2- enethioate. (7a-7f) and antifungal activity of (e)-s-4-(isonicotinamido)-5-(phenoxymethyl)-4h-1, 2, 4-triazol-3-yl 3-(substituted phenyl) prop-2-enethioate. (7a-7f), antitubercular activity of against mycobacterium tuberculosis h37rv presented the scope of this paper.
23
Lim, Dong-Jin. "Methylene Blue-Based Nano and Microparticles: Fabrication and Applications in Photodynamic Therapy." Polymers 13, no. 22 (2021): 3955. http://dx.doi.org/10.3390/polym13223955.
Texto completo da fonteResumo:
Methylene blue (MB) has been used in the textile industry since it was first extracted by the German chemist Heinrich Caro. Its pharmacological properties have also been applied toward the treatment of certain diseases such as methemoglobinemia, ifosfamide-induced encephalopathy, and thyroid conditions requiring surgery. Recently, the utilization of MB as a safe photosensitizer in photodynamic therapy (PDT) has received attention. Recent findings demonstrate that photoactivated MB exhibits not only anticancer activity but also antibacterial activity both in vitro and in vivo. However, due to the hydrophilic nature of MB, it is difficult to create MB-embedded nano- or microparticles capable of increasing the clinical efficacy of the PDT. This review aims to summarize fabrication techniques for MB-embedded nano and microparticles and to provide both in vitro and in vivo examples of MB-mediated PDT, thereby offering a future perspective on improving this promising clinical treatment modality. We also address examples of MB-mediated PDT in both cancer and infection treatments. Both in-vitro and in-vivo studies are summarized here to document recent trends in utilizing MB as an effective photosensitizer in PDT. Lastly, we discuss how developing efficient MB-carrying nano- and microparticle platforms would be able to increase the benefits of PDT.
24
Lis, Manuel J., Bianca Bastos Caruzi, Guilherme Andreoli Gil, et al. "In-Situ Direct Synthesis of HKUST-1 in Wool Fabric for the Improvement of Antibacterial Properties." Polymers 11, no. 4 (2019): 713. http://dx.doi.org/10.3390/polym11040713.
Texto completo da fonteResumo:
The use of Metal-Organic Frameworks (MOF) such as HKUST-1 in textiles is an alternative with regard to the development of technologies that are increasingly seeking for functionalities, mainly in the fields of health and hygiene, named biofunctional fabrics. However, the application of the MOF under the surface of the wool fiber can lead to a low durability finish due to its low fixation. Thus, this project aims to perform the direct synthesis of HKUST in the wool fiber, so that a product with good washing durability can be obtained. The purpose of this study was to incorporate metal-organic frameworks, composed of copper and trimesic acid, into woolen fabrics, to improve the antibacterial properties. The synthesis was performed directly in the wool fabric, at time intervals of 24 and 48 h. The resulting fabrics were characterized by Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), X-Ray Diffractometry (XRD), Fourier Transform Spectroscopy Infrared-Attenuated Total Reflectance (FTIR-ATR), and colorimetric analysis (CIElab), and the Antimicrobial Activity Test (American Association of Textile Chemist and Colourists - AATCC Test Method 61-2007-2A) was performed. The results suggested that the application produced textiles with antibacterial properties, showing activity against Escherichia coli.
25
Shul'pin, Georgiy B. "ChemInform Abstract: C-H Functionalization: Thoroughly Tuning Ligands at a Metal Ion, a Chemist Can Greatly Enhance Catalyst′s Activity and Selectivity." ChemInform 44, no. 47 (2013): no. http://dx.doi.org/10.1002/chin.201347223.
Texto completo da fonte
26
Rathore, Swati, Shweta Mishra, Debarshi K. Mahapatra, Shailendra Patil, and Asmita G. Patil. "Thoughtful Insights into the Therapeutic Armamentarium of Chalcones: 10 Years of Glorious Journey." Current Bioactive Compounds 16, no. 6 (2020): 747–808. http://dx.doi.org/10.2174/1573407215666190411150734.
Texto completo da fonteResumo:
Background: Naturally occurring chalcones afford diverse pharmacological activities such as anticancer, anti-malarial, anti-inflammatory, anti-tubercular, anti-hypertensive, anti-arrhythmic, antidiabetic, anti-angiogenic, anti-obesity, antiplatelet, anti-oxidant, hypolipidemic and anti-gout. They are frequently being used by the various researchers to design and develop new synthetic chalcones and many novel hybrid analogs as bioactive drugs. Many of these drugs are hybrid molecules, which are designed through molecular hybridization theory, and have displayed multiple pharmacological and medicinal aspects. This multi-effective feature of these hybrid derivatives makes them efficient and ideal drug entities for the treatment of various dreadful diseases. Methods: A structured search of published research literature from recognized standard medical databases such as PubMed, Google Scholar, Google Patents, Scopus, etc., over the defined period of 10 years (January 2009 to December 2018) have been performed. Various reported heterocyclic chalcone hybrids, their synthesis methods, plausible mechanism(s) of action(s), and probable structure-activity relationships for the therapeutic applications in cancer, malaria, tuberculosis, leishmaniasis, inflammation, diabetes, microbial infection, and cardiovascular diseases remained the centre for attraction of this article. Results: The present review article focuses on chalcone hybrids with different heterocyclic moieties and categorizing them on the basis of their pharmacology and therapeutic significance in the last ten years and has proposed their structure-activity relationships. Conclusion: Chalcone and their hybrids have largely been targeted for their anticancer, anti-malarial, anti-inflammatory, anti-tubercular, antileishmaniasis, and anti-microbial activity. This comprehensive study may assist the medicinal chemist to design and develop innovative chalcone hybrids with significant therapeutic activity.
27
Chalid, Sri Yadial, Pratiwi Nur Kinasih, Fitriah Hatiningsih, and Tarso Rudiana. "Antioxidant Activities and Profile of Amino Acid of Yoghurt from Beef Milk Fermentation with Dadih Starter." Jurnal Kimia Valensi 7, no. 1 (2021): 58–68. http://dx.doi.org/10.15408/jkv.v7i1.20425.
Texto completo da fonteResumo:
Dadih is naturally fermented buffalo milk in bamboo tubes and known to have antioxidant, antibacterial, and antihypertensive activity. Lactic acid bacteria in dadih can use as a starter to produce yogurt. The study aimed to produce yogurt of cow's milk with dadih as a starter, to determine the antioxidant activity and amino acid composition. Dadih is added with concentration variation of 2.5; 5; 7.5 and 10% (v/v) and it fermented for 48 hours at room temperature. Lactic acid bacteria cell counts of dadih were calculated by the total plate count method. Yogurt was tested by organoleptics with 33 panelists and proximate analysis water, ash, fat and protein contens based on the Association of Official Analytical Chemist (AOAC) in 2005. Antioxidant activities of yogurt were tested by DPPH method (1,1-diphenyl-2-picrylhydrazyl). Amino acid composition of yogurt was analyzed using ultra performance liquid chromatography (UPLC). The research result of amount of LAB on dadih are 1.01 x 1011 CFU/mL, has fulfilled the requirements of SNI 2981: 2009. Yogurt produced with the addition of dadih by 10% (v/v) is most accepted by panelists. The highest antioxidant activity was obtained by yogurt with 2.5% addition of dadih with IC50 value of 78.28 ppm. Yogurt almost contain all essential and non-essensial amino acids including tyrosine and phenylalanine as the antioxidants. Measurement of water, ash, protein and fat content in the sample meets the requirements of SNI 2981: 2009.
28
Chalid, Sri Yadial, Pratiwi Nur Kinasih, Fitriah Hatiningsih, and Tarso Rudiana. "Antioxidant Activities and Profile of Amino Acid of Yoghurt from Beef Milk Fermentation with Dadih Starter." Jurnal Kimia Valensi 1, no. 1 (2021): 58–68. http://dx.doi.org/10.15408/jkv.v1i1.20425.
Texto completo da fonteResumo:
Dadih is naturally fermented buffalo milk in bamboo tubes and known to have antioxidant, antibacterial, and antihypertensive activity. Lactic acid bacteria in dadih can use as a starter to produce yogurt. The study aimed to produce yogurt of cow's milk with dadih as a starter, to determine the antioxidant activity and amino acid composition. Dadih is added with concentration variation of 2.5; 5; 7.5 and 10% (v/v) and it fermented for 48 hours at room temperature. Lactic acid bacteria cell counts of dadih were calculated by the total plate count method. Yogurt was tested by organoleptics with 33 panelists and proximate analysis water, ash, fat and protein contens based on the Association of Official Analytical Chemist (AOAC) in 2005. Antioxidant activities of yogurt were tested by DPPH method (1,1-diphenyl-2-picrylhydrazyl). Amino acid composition of yogurt was analyzed using ultra performance liquid chromatography (UPLC). The research result of amount of LAB on dadih are 1.01 x 1011 CFU/mL, has fulfilled the requirements of SNI 2981: 2009. Yogurt produced with the addition of dadih by 10% (v/v) is most accepted by panelists. The highest antioxidant activity was obtained by yogurt with 2.5% addition of dadih with IC50 value of 78.28 ppm. Yogurt almost contain all essential and non-essensial amino acids including tyrosine and phenylalanine as the antioxidants. Measurement of water, ash, protein and fat content in the sample meets the requirements of SNI 2981: 2009.
29
Medici, Serenella, Massimiliano Peana, Alessio Pelucelli, and Maria Antonietta Zoroddu. "Rh(I) Complexes in Catalysis: A Five-Year Trend." Molecules 26, no. 9 (2021): 2553. http://dx.doi.org/10.3390/molecules26092553.
Texto completo da fonteResumo:
Rhodium is one of the most used metals in catalysis both in laboratory reactions and industrial processes. Despite the extensive exploration on “classical” ligands carried out during the past decades in the field of rhodium-catalyzed reactions, such as phosphines, and other common types of ligands including N-heterocyclic carbenes, ferrocenes, cyclopentadienyl anion and pentamethylcyclopentadienyl derivatives, etc., there is still lively research activity on this topic, with considerable efforts being made toward the synthesis of new preformed rhodium catalysts that can be both efficient and selective. Although the “golden age” of homogeneous catalysis might seem over, there is still plenty of room for improvement, especially from the point of view of a more sustainable chemistry. In this review, temporally restricted to the analysis of literature during the past five years (2015–2020), the latest findings and trends in the synthesis and applications of Rh(I) complexes to catalysis will be presented. From the analysis of the most recent literature, it seems clear that rhodium-catalyzed processes still represent a stimulating challenge for the metalloorganic chemist that is far from being over.
30
Thornber, Karen L. "Literature, Asia, and the Anthropocene: Possibilities for Asian Studies and the Environmental Humanities." Journal of Asian Studies 73, no. 4 (2014): 989–1000. http://dx.doi.org/10.1017/s0021911814001569.
Texto completo da fonteResumo:
The term “Anthropocene,” coined in the 1980s by the ecologist Eugene F. Stoermer and popularized at the turn of the twenty-first century by the atmospheric chemist and Nobel laureate Paul Crutzen, has been used increasingly in the past decade to highlight human activity as a geological force and to underscore the rapidly escalating impacts of human behaviors on the planet—sufficient, many have argued, to launch a new geological age. While geologists and environmentalists continue to debate the validity of Anthropocene as a formal designation, climate change; mass extinctions of plant and animal species; and widespread pollution of sky, sea, and land make clear the extent to which humans have shaped global ecologies. An understanding of Asia—home to more than half the world's population, an increasingly significant contributor to global carbon dioxide emissions, the site of the Third Pole, and an area acutely vulnerable to climate change and rising sea levels—is vital to an understanding of the physical, chemical, biological, and cultural processes that comprise the Anthropocene.
31
Battistoni, Alyssa. "Anthropocene Politics." Perspectives on Politics 18, no. 3 (2020): 881–85. http://dx.doi.org/10.1017/s1537592720001887.
Texto completo da fonteResumo:
AbstractThose for whom the term “Anthropocene” tends to evoke academic faddishness may be surprised to realize that the discourse about it is now two decades old. The term was first proposed in a 2000 paper by the atmospheric chemist Paul Crutzen and biologist Eugene Stoermer to describe the geological epoch in which human activity has come to shape the Earth itself. Since then, the concept has generated a vast amount of scholarly conversation and a wide range of interpretations, often concerning the start date of this new era: Did the “age of man” begin with the use of fire? The development of settled agriculture? The rise of capitalism? European settlement of the Americas? And so on. Although these debates have raged across the humanities and sciences for years, political theorists have largely kept their distance. As the climate crisis worsens, however, many may now be looking to play catch-up. If so, each of the three books under review here holds out the promise of helping us understand the theoretical implications of this epochal transformation.
32
Poier, Dario, Sharon Mitchell, Victor Tulus, Gonzalo Guillén-Gosálbez, Javier Pérez-Ramírez, and Roger Marti. "Aiming for More Sustainable Cross-Coupling Chemistry by Employing Single-Atom Catalysis on Scale." CHIMIA 77, no. 3 (2023): 127. http://dx.doi.org/10.2533/chimia.2023.127.
Texto completo da fonteResumo:
Scaling up syntheses from mg to kg quantities is a complex endeavor. Besides adapting laboratory protocols to industrial processes and equipment and thorough safety assessments, much attention is paid to the reduction of the process’ environmental impact. For processes including transition metal catalyzed steps, e.g. cross-coupling chemistry, this impact strongly depends on the identity of the metal used. As such, a key approach is the replacement of single-use with reusable heterogeneous catalysts. Transition metal single-atom heterogeneous catalysts (SAC), a novel class of catalytic materials, might exhibit all the necessary properties to step up to this task. This article shall discuss current applications of SAC in cross-coupling chemistry from the point of a process chemist and shed light on the NCCR Catalysis contribution to the field. Investigations of the stability-activity-selectivity relationship of SACs in combination with early-stage life-cycle assessments (LCA) of potential processes lay the foundation for large-scale application tailored catalyst synthesis. Ultimately, prevailing challenges are highlighted, which need to be addressed in future research.
33
Al-Zubaidi, Ez al-Din Khazal Najm. "The catechins profile and antioxidant activity in different types of green tea bags." Journal of Misan Researches 16, no. 31 (2021): 279–98. http://dx.doi.org/10.52834/jmr.v16i31.32.
Texto completo da fonteResumo:
Tea and mainly green tea as a rich source of antioxidants has been widely known for some time. The antioxidant capacity of tea including green tea is mainly due to its catechins content. The objective of this study was to determine the relationship between the ORAC value and the catechins content. Regular and decaffeinated commercial green tea bags commonly consumed in the United Kingdom (UK) have been examined using Reversed-Phase High-pressure Liquid Chromatography (RP-HPLC). Teabags were purchased from different local supermarkets in the UK and extracted with natural mineral water at temperature 100°C for 9 minutes at the pre-adjusted pH 4. The level of four catechins (Epi-structured) for the thirteen types of green tea were separated and determined by HPLC analysis, i.e. ()-epigallocatechin (EGC), ()-epicatechin (EC), ()-epigallocatechin-3-gallate (EGCG) and ()-epicatechin gallate (ECG). The standard graphs were validated using certified reference catechins supplied by the Laboratory of the Government Chemist (LGC). The levels of total catechins and oxygen radical absorbance capacity (ORAC) values varied from 34.61to 204.55 mg/g, 830.19- 4197.81 Trolox equivalents/g tea bags for thirteen types of green teas respectively. It was clear from the results of this study that there was a significant linear and positive correlation (r = 0.951, df = 12, p < 0.05) is found to exist between the total catechins contents and ORAC values. It can be concluded that the results of catechins measurements coupled to this; the well-known ORAC assay was successfully modified to measure the antioxidant capacity of the green tea extracts throughout this study. Furthermore, the higher the level of catechins the higher is the antioxidant capacity of the tea. This may stimulus consumers in selecting the type of tea and tea brewing times, exhibiting more health benefits. Nevertheless, the differences between the studied brands are owing to shelf life, production and storage conditions.
 
34
Campora, Marta, Valeria Francesconi, Silvia Schenone, Bruno Tasso, and Michele Tonelli. "Journey on Naphthoquinone and Anthraquinone Derivatives: New Insights in Alzheimer’s Disease." Pharmaceuticals 14, no. 1 (2021): 33. http://dx.doi.org/10.3390/ph14010033.
Texto completo da fonteResumo:
Alzheimer’s disease (AD) is a progressive neurodegenerative disease that is characterized by memory loss, cognitive impairment, and functional decline leading to dementia and death. AD imposes neuronal death by the intricate interplay of different neurochemical factors, which continue to inspire the medicinal chemist as molecular targets for the development of new agents for the treatment of AD with diverse mechanisms of action, but also depict a more complex AD scenario. Within the wide variety of reported molecules, this review summarizes and offers a global overview of recent advancements on naphthoquinone (NQ) and anthraquinone (AQ) derivatives whose more relevant chemical features and structure-activity relationship studies will be discussed with a view to providing the perspective for the design of viable drugs for the treatment of AD. In particular, cholinesterases (ChEs), β-amyloid (Aβ) and tau proteins have been identified as key targets of these classes of compounds, where the NQ or AQ scaffold may contribute to the biological effect against AD as main unit or significant substructure. The multitarget directed ligand (MTDL) strategy will be described, as a chance for these molecules to exhibit significant potential on the road to therapeutics for AD.
35
Holikova, Olena. "Formalisation of agricultural research." Linguistics and Culture Review 5, S4 (2021): 1137–53. http://dx.doi.org/10.21744/lingcure.v5ns4.1751.
Texto completo da fonteResumo:
As an independent component of modern research in natural sciences, branch research developed as a result of the accumulation of knowledge from three spheres of public activity – agriculture, branch-specific education, and agricultural research – under the influence of a complex interaction of many external factors. The purpose of this study is to investigate the initial stage of formalization of agricultural research as a branch of natural sciences with the development of corresponding sign-symbolic systems and terminology. Based on the study of printed and archival research of the Imperial Free Economic Society (IFES), adjustments were made to the scientific periodization of the history of research as a branch of knowledge, considering the personalized contribution of its luminaries. Forgotten or little-known studies of pioneers of Ukrainian research – the IFES members: Swiss mathematician L. Euler; Russian scientist of Swedish origin, botanist and chemist E.G. Laxman; a native of Chernihiv Region, Professor of agriculture V. P. Prokopovich, and others were introduced into scientific discourse. The present paper analyses the areas of diverse research activities in agriculture, which were conducted by IFES figures at the early stages of the first scientific and economic association in the Russian Empire.
36
Javaid, Muhammad, and Muhammad Imran. "Editorial: Topological investigations of chemical networks." Main Group Metal Chemistry 44, no. 1 (2021): 267–69. http://dx.doi.org/10.1515/mgmc-2021-0030.
Texto completo da fonteResumo:
Abstract The topic of computing the topological indices (TIs) being a graph-theoretic modeling of the networks or discrete structures has become an important area of research nowadays because of its immense applications in various branches of the applied sciences. TIs have played a vital role in mathematical chemistry since the pioneering work of famous chemist Harry Wiener in 1947. However, in recent years, their capability and popularity has increased significantly because of the findings of the different physical and chemical investigations in the various chemical networks and the structures arising from the drug designs. In additions, TIs are also frequently used to study the quantitative structure property relationships (QSPRs) and quantitative structure activity relationships (QSARs) models which correlate the chemical structures with their physio-chemical properties and biological activities in a dataset of chemicals. These models are very important and useful for the research community working in the wider area of cheminformatics which is an interdisciplinary field combining mathematics, chemistry, and information science. The aim of this editorial is to arrange new methods, techniques, models, and algorithms to study the various theoretical and computational aspects of the different types of these topological indices for the various molecular structures.
37
Clary, David C., and Brian J. Orr. "Amyand David Buckingham. 28 January 1930—4 February 2021." Biographical Memoirs of Fellows of the Royal Society 72 (December 8, 2021): 77–99. http://dx.doi.org/10.1098/rsbm.2021.0026.
Texto completo da fonteResumo:
David Buckingham was a chemical physicist and theoretical chemist who made fundamental contributions to the understanding of optical, electric and magnetic properties of molecules. Born in Australia, he was an undergraduate at the University of Sydney and the first PhD research student of John Pople (FRS 1961) at Cambridge, and there he made significant advances in the theory of intermolecular forces and nonlinear optics. He then moved to Oxford, where he and his group performed the first direct measurement of a molecular electric quadrupole moment. He was elected to the first chair of theoretical chemistry at the University of Bristol, where he wrote a particularly influential article on molecular moments, higher-order polarizabilities and intermolecular forces. His next appointment was at the University of Cambridge as the first holder of the 1968 Chair of Chemistry, and he was head of a distinguished department of theoretical chemistry for 28 years. With colleagues he pioneered experiment and theory on vibrational optical activity and developed a powerful model to predict the structures of weakly-bound molecules. A man of broad interests and achievements, he played first class cricket in the 1950s.
38
Papp-Wallace, Krisztina M., Andrea Endimiani, Magdalena A. Taracila, and Robert A. Bonomo. "Carbapenems: Past, Present, and Future." Antimicrobial Agents and Chemotherapy 55, no. 11 (2011): 4943–60. http://dx.doi.org/10.1128/aac.00296-11.
Texto completo da fonteResumo:
ABSTRACTIn this review, we summarize the current “state of the art” of carbapenem antibiotics and their role in our antimicrobial armamentarium. Among the β-lactams currently available, carbapenems are unique because they are relatively resistant to hydrolysis by most β-lactamases, in some cases act as “slow substrates” or inhibitors of β-lactamases, and still target penicillin binding proteins. This “value-added feature” of inhibiting β-lactamases serves as a major rationale for expansion of this class of β-lactams. We describe the initial discovery and development of the carbapenem family of β-lactams. Of the early carbapenems evaluated, thienamycin demonstrated the greatest antimicrobial activity and became the parent compound for all subsequent carbapenems. To date, more than 80 compounds with mostly improved antimicrobial properties, compared to those of thienamycin, are described in the literature. We also highlight important features of the carbapenems that are presently in clinical use: imipenem-cilastatin, meropenem, ertapenem, doripenem, panipenem-betamipron, and biapenem. In closing, we emphasize some major challenges and urge the medicinal chemist to continue development of these versatile and potent compounds, as they have served us well for more than 3 decades.
39
Swyngedouw, Erik. "Depoliticized Environments: The End of Nature, Climate Change and the Post-Political Condition." Royal Institute of Philosophy Supplement 69 (September 22, 2011): 253–74. http://dx.doi.org/10.1017/s1358246111000300.
Texto completo da fonteResumo:
Nobel-price winning atmospheric chemist Paul Crutzen introduced in 2000 the concept of the Anthropocene as the name for the successor geological period to the Holocene. The Holocene started about 12,000 years ago and is characterized by the relatively stable and temperate climatic and environmental conditions that were conducive to the development of human societies. Until recently, human development had relatively little impact on the dynamics of geological time. Although disagreement exists over the exact birth date of the Anthropocene, it is indisputable that the impact of human activity on the geo-climatic environment became more pronounced from the industrial revolution onwards, leading to a situation in which humans are now widely considered to have an eco-geologically critical impact on the earth's bio-physical system. The most obvious example is the accumulation of greenhouse gases like CO2and Methane (CH4) in the atmosphere and the changes this induces in climatic dynamics. Others are the growing homogenization of biodiversity as a result of human-induced species migration, mass extinction and bio-diversity loss, the manufacturing of new (sub-)species through genetic modification, or the geodetic consequences resulting from, for example, large dam construction, mining and changing sea-levels.
40
Lumley, James A., Gary Sharman, Thomas Wilkin, Matthew Hirst, Carlos Cobas, and Michael Goebel. "A KNIME Workflow for Automated Structure Verification." SLAS DISCOVERY: Advancing the Science of Drug Discovery 25, no. 8 (2020): 950–56. http://dx.doi.org/10.1177/2472555220907091.
Texto completo da fonteResumo:
Adequate characterization of chemical entities made for biological screening in the drug discovery context is critical. Incorrectly characterized structures lead to mistakes in the interpretation of structure–activity relationships and confuse an already multidimensional optimization problem. Mistakes in the later use of these compounds waste money and valuable resources in a discovery process already under cost pressure. Left unidentified, these errors lead to problems in project data packages during quality review. At worst, they put intellectual property and patent integrity at risk. We describe a KNIME workflow for the early and automated identification of these errors during registration of a new chemical entity into the corporate screening catalog. This Automated Structure Verification workflow provides early identification (within 24 hours) of missing or inconsistent analytical data and therefore reduces any mistakes that inevitably get made. Automated identification removes the burden of work from the chemist submitting the compound into the registration system. No additional work is required unless a problem is identified and the submitter alerted. Before implementation, 14% of samples within the existing sample catalog were missing data on initial pass. A year after implementation, only 0.2% were missing data.
41
Holikova, Olena. "Scientific and organizational principles of agricultural research in 18-19th centuries." RIVISTA DI STUDI SULLA SOSTENIBILITA' 12, no. 2 (2023): 143–64. http://dx.doi.org/10.3280/riss2022-002010.
Texto completo da fonteResumo:
As an independent component of modern research in natural sciences, branch re-search developed as a result of the accumulation of knowledge from three spheres of public activity - agriculture, branch-specific education, and agricultural re-search - under the influence of a complex interaction of many external factors. The purpose of this study is to investigate the initial stage of formalization of agri-cultural research as a branch of natural sciences with the development of a corre-sponding sign-symbolic system and terminology. Based on the study of printed and archival research of the Imperial Free Economic Society (IFES), adjustments were made to the scientific periodization of the history of research as a branch of knowledge, considering the personalized contribution of its luminaries. Forgotten or little-known studies of pioneers of Ukrainian research - the IFES members: Swiss mathematician Euler; Russian scientist of Swedish origin, botanist and chemist Laxman; a native of Chernihiv Region, Professor of agriculture Prokopovich, and others were introduced into scientific discourse. The present paper analyses the ar-eas of diverse research activities in agriculture, which were conducted by IFES fig-ures at the early stages of the first scientific and economic association in the Rus-sian Empire.
42
Goswami, Arunava. "Aspirin in a new role in human body." Journal of Medical pharmaceutical and allied sciences 12, no. 6 (2023): 6281–84. http://dx.doi.org/10.55522/jmpas.v12i6.5834.
Texto completo da fonteResumo:
In 1897, German chemist Felix Hoffman synthesized acetylsalicylic acid, known as aspirin, which revolutionized its widespread modern use for pain relief. Aspirin acts as an inhibitor of cyclooxygenase-1 (COX-1) and has a modifying effect on the enzymatic activity of cyclooxygenase-2 (COX-2). It inhibits the production of prostaglandins, crucial for various physiological processes, and has been linked to a reduced risk of pre-eclampsia and preterm delivery before 34 weeks of pregnancy. However, aspirin's COX-1 inhibition is irreversible and long-lasting, requiring new enzymes to replace those acetylated. Low-dose aspirin has been reported to increase bone mineral density (BMD) in elderly individuals, coinciding with the growing prevalence of osteoporosis. However, a definitive connection between the use of low-dose aspirin and BMD remains elusive. A study examined the relationship between low-dose aspirin use and BMD in adults aged 50 to 80. A higher BMD in the femur, intertrochanter, and L1 regions compared to those who do not use aspirin was reported. However, the abstract acknowledges limitations and emphasizes the need for future research, including randomized controlled trials, to establish a causal relationship between low-dose aspirin use and enhanced bone density.
43
Земцова, С. И. "THE SUBJECT OF INTERROGATION OF THE “CHEMIST”, “COOKER”, “SUPPLIER”, “CURATOR” AND ORGANIZER DURING THE INVESTIGATION OF THE IDENTIFIED DRUG PRODUCTION." Digest of research works "Criminalistics: yesterday, today, tomorrow", no. 3(23) (September 30, 2022): 74–83. http://dx.doi.org/10.55001/2587-9820.2022.42.41.007.
Texto completo da fonteResumo:
В статье акцентируется внимание на значительном увеличении количества выявленных правоохранительными органами преступлений, связанных с производством синтетических наркотических средств в лабораториях «конструкторского типа», совершенных организованными преступными группами (сообществами). Отмечается, что, как правило, эта деятельность взаимосвязана с последующим незаконным сбытом с использованием интернет-магазинов и легализацией наркодоходов. Обращается внимание на необходимость разработки полноценной методики расследования данного вида преступлений с учетом существенной трансформации способа совершения преступления. На основе анализа судебно-следственной практики формулируются предложения по оптимизации одного из элементов методики — тактики производства допроса подозреваемых (обвиняемых). Обосновывается совокупность обстоятельств, подлежащих установлению при производстве допроса отдельных участников наркопроизводства: «химика», «варщика», «поставщика», «куратора» и организатора. The author focuses on a significant increase in the number of crimes related to the production of synthetic narcotic drugs in drug laboratories of the “design type” committed by organized criminal groups (communities) in the article. It is emphasized that this activity is interconnected with the subsequent illegal sale using online stores and the legalization of drug proceeds. Attention is drawn to the need develop a full-fledged methodology for investigating this type of crime, taking into account the significant transformation the method of committing a crime. Based on the analysis of judicial and investigative practice, proposals are formulated to optimize one of the elements of the methodology — the tactics of interrogation of suspects (accused). The author substantiates the totality of circumstances to be established during the in-terrogation of individual participants in drug production: “chemist”, “brewer”, “supplier”, “cura-tor” and organizer.
44
Salar, Uzma, Khalid M. Khan, Almas Jabeen, et al. "ROS Inhibitory Activity and Cytotoxicity Evaluation of Benzoyl, Acetyl, Alkyl Ester, and Sulfonate Ester Substituted Coumarin Derivatives." Medicinal Chemistry 16, no. 8 (2020): 1099–111. http://dx.doi.org/10.2174/1573406415666190826153001.
Texto completo da fonteResumo:
Background: A number of non-steroidal anti-inflammatory drugs (NSAIDs) including aspirin, indomethacin, ibuprofen, flufenamic acid, and phenylbutazone are being clinically used to treat inflammatory disorders. These NSAIDs are associated with serious side effects such as gastric ulceration, nephrotoxicity, and bleeding. Therefore, the identification of potent and safe therapy for inflammatory disorders is still of great interest to the medicinal chemist. Methods: A series of varyingly substituted benzoyl, acetyl, alkyl ester, and sulfonate ester substituted coumarins 1-64 were screened for the inhibition of ROS, generated from zymosan activated whole blood phagocytes, using luminol-enhanced chemiluminescence technique. Results: Among all tested compounds, 8 (IC50 = 65.0 ± 3.1 μM), 24 (IC50 = 41.8 ± 1.5 μM), 26 (IC50 = 10.6 ± 2.8 μM), 28 (IC50 = 20.9 ± 1.5 μM), and 41 (IC50 = 4.6 ± 0.3 μM) showed good anti- inflammatory potential as compared to standard antiinflammatory drug ibuprofen (IC50 = 54.3 ± 1.9 μM). Specifically, compounds 24, 26, 28, and 41 showed superior activity than standard antiinflammatory drug. Furthermore, compounds 12 (IC50 = 219.0 ± 1.4 μM), 14 (IC50 = 216.5 ± 6.2 μM), 16 (IC50 = 187.4 ± 2.2 μM), and 20 (IC50 = 196.2 ± 2.0 μM) showed moderate ROS inhibitory activity. Limited SAR study revealed that the hydroxy-substituted compound showed better ROS inhibition potential in case of 3-benzoyl and 3-ethylester coumarin derivatives. Whereas, chloro substitution was found to be important in case of 3-acetyl coumarin derivatives. Similarly, in case of sulfonate ester, chloro, and nitro groups especially at positions -4 and -3 of ring “R” played vital role in ROS inhibition. Furthermore, cytotoxicity of all active compounds was also checked on NIH-3T3 cell line. Compounds 12, 14, and 20 were found to be non-cytotoxic. Whereas, 8, 16, 24, 26, 28, and 41 were found to be very weak cytotoxic as compared to standard cycloheximide (IC50 = 0.13 ± 0.02 μM). Conclusion: Identified ROS inhibitors offer the possibility of additional modifications that could give rise to lead structures for further research in order to obtain more potent, and safer antiinflammatory agent.
45
Issa, Tahani Osman, Ahmed Ibrahim Mohamed Ahmed, Yahya Sulieman Mohamed, Sakina Yagi, Abdelrafie Mohamed Makhawi, and Tarig Osman Khider. "Physiochemical, Insecticidal, and Antidiabetic Activities of Senna occidentalis Linn Root." Biochemistry Research International 2020 (September 15, 2020): 1–9. http://dx.doi.org/10.1155/2020/8810744.
Texto completo da fonteResumo:
The present study aimed to investigate the physiochemical activities of Senna occidentalis (Linn) roots and phytochemicals as insecticidal (ethyl acetate and methanol) and antidiabetic (ethanolic extract) activities. Physicochemical properties were carried out by using Association of Official Analytical Chemist methods; thin layer chromatography was carried out according to the Stahl method. Larvicidal activity and LD50 were studied against the third instar of Culex quinquefasciatus mosquito larvae to detect and extract toxicity. The ethanolic extracts of the roots were orally tested at the dose 200 mg/kg for the hypoglycemic effect on induced hyperglycemia in normal rats, assessed in the ethanol extract, and were compared with diabetic control and standards glibenclamide 10 mg/kg. Physiochemical parameters showed high rate in the nitrogen-free extract (69.6%), curd fiber (14.5%), crude proteins (8.15%), ether extract (3.75%), and both ash and moisture (2%), and high concentrations values were found in potassium (43 mg/l) followed by phosphorous (28.5 mg/l), calcium (15 mg/l), sodium (3.65 mg/l), and magnesium (0.145 mg/l). In this part, phytochemical compounds showed high amount of alkaloids, triterpene, flavonoids, tannins, sugars, and few amount of anthraquinone glycosides. Thin-layer chromatography (TLC) studies different colored phytochemical constituted with different Rf values. All the spots are colored under UV light, but some are localized colorless after spaying. The ethyl acetate (EtAc) extract showed eight spots, and the methanol (MeOH) extract showed thirteen spots. The larvicidal activity showed that the ethyl acetate extract was safe against mosquito larvae with an LD50 value 1412.54 (p<0.05), and the methanol extract had moderate larvicidal activity against mosquito larvae with an LD50 value 257.54 (p<0.05), while the ethanolic extract of Senna occidentalis (L.) causes a favorable hypoglycemic activity when compared to control significant reduction by [53.15%, 32.87%, and 20.94%], respectively, as well as standard glibenclamide. Based on the various data of the physicochemical parameters, TLC spots, and phytochemical compounds of Senna occidentalis root, they could be used as references standards for manufacturing units of Senna occidentalis root larvicidal and antidiabetic drugs.
46
Ashraful Alam, Md, Muhammad Usman Ghani, Muhammad Kamran, Muhammad Shazib Hameed, Riaz Hussain Khan, and A. Q. Baig. "Degree-Based Entropy for a Non-Kekulean Benzenoid Graph." Journal of Mathematics 2022 (June 6, 2022): 1–12. http://dx.doi.org/10.1155/2022/2288207.
Texto completo da fonteResumo:
Tessellations of kekulenes and cycloarenes have a lot of potential as nanomolecular belts for trapping and transporting heavy metal ions and chloride ions because they have the best electronic properties and pore sizes. The aromaticity, superaromaticity, chirality, and novel electrical and magnetic properties of a class of cycloarenes known as kekulenes have been the subject of several experimental and theoretical studies. Through topological computations of superaromatic structures with pores, we investigate the entropies and topological characterization of different tessellations of kekulenes. Using topological indices, the biological activity of the underlying structure is linked to its physical properties in (QSPR/QSAR) research. There is a wide range of topological indices accessible, including degree-based indices, which are used in this work. With the total π -electron energy, these indices have a lot of iteration. In addition, we use graph entropies to determine the structural information of a non-Kekulean benzenoid graph. In this article, we study the crystal structure of non-Kekulean benzenoid graph K n and then calculate some entropies by using the degree-based topological indices. We also investigate the relationship between degree-based topological indices and degree-based entropies. This relationship is very helpful for chemist to study the physicochemical characterization of non-Kekulean benzenoid chemical. These numerical values correlate with structural facts and chemical reactivity, biological activities, and physical properties.
47
Ashraful Alam, Md, Muhammad Usman Ghani, Muhammad Kamran, Muhammad Shazib Hameed, Riaz Hussain Khan, and A. Q. Baig. "Degree-Based Entropy for a Non-Kekulean Benzenoid Graph." Journal of Mathematics 2022 (June 6, 2022): 1–12. http://dx.doi.org/10.1155/2022/2288207.
Texto completo da fonteResumo:
Tessellations of kekulenes and cycloarenes have a lot of potential as nanomolecular belts for trapping and transporting heavy metal ions and chloride ions because they have the best electronic properties and pore sizes. The aromaticity, superaromaticity, chirality, and novel electrical and magnetic properties of a class of cycloarenes known as kekulenes have been the subject of several experimental and theoretical studies. Through topological computations of superaromatic structures with pores, we investigate the entropies and topological characterization of different tessellations of kekulenes. Using topological indices, the biological activity of the underlying structure is linked to its physical properties in (QSPR/QSAR) research. There is a wide range of topological indices accessible, including degree-based indices, which are used in this work. With the total π -electron energy, these indices have a lot of iteration. In addition, we use graph entropies to determine the structural information of a non-Kekulean benzenoid graph. In this article, we study the crystal structure of non-Kekulean benzenoid graph K n and then calculate some entropies by using the degree-based topological indices. We also investigate the relationship between degree-based topological indices and degree-based entropies. This relationship is very helpful for chemist to study the physicochemical characterization of non-Kekulean benzenoid chemical. These numerical values correlate with structural facts and chemical reactivity, biological activities, and physical properties.
48
Skorokhodova, Tatiana G. "To the Origins of Studies of Science in India: Prafullachandra Ray on the Development of Science Problems in Modernizing Society. Ray, Prafullachandra, The Bengali Brain and Its Misuse, Translated by Tatiana G. Skorokhodova." Voprosy Filosofii, no. 1 (2022): 159–85. http://dx.doi.org/10.21146/0042-8744-2022-1-159-185.
Texto completo da fonteResumo:
Modern Indian intellectual history has rich sources for research of non-Western studies of science. Genesis of Indian studies of science belongs to the colonial epoch, when the scientists attempted to study a history of indigenous scientific knowledge as well as to think the circumstances of decline and further Modern development of sciences in India. The thoughtful example of work in studies of science area is an essay ‘The Bengali Brain and Its Misuse’ (1910) by Indian chemist Prafullachandra Ray (1861–1944). The article’s aim is to present the social and philosophical meanings of the essay in broad context of intellectual and cultural development of the Bengal Renaissance. Externally presenting an attempt to comprehend social causes of impossibility of ‘scientific revolution’ in India in comparison with Europe and ones of retardation of Bengal sociocultural community in the most important spheres of activity, P. Ray forms practically the first approach to Indian philosophy of science. Science is interpreted as the derivative from human ‘spirit of inquiry’, and the foundation for cognitive effort is rationalism, which encourages to raise bold questions and to doubt any authority. From sociology of science point of view, a decline of science knowledge and misuse of intellectual efforts P. Ray treats as consequence of Brahmins’ monopoly of the knowledge, of the caste system and misunderstanding of high education value in modernizing society’s circumstances.
49
Apchel, Vasiliy Ya, and Viktor N. Golubev. "Professor Alexander Mozzhukhin (by the 100th anniversary of his birth)." Bulletin of the Russian Military Medical Academy 23, no. 3 (2021): 247–52. http://dx.doi.org/10.17816/brmma71592.
Texto completo da fonteResumo:
Alexander Sergeevich Mozzhukhin was born on August 27, 1921, in Krasnsodar in a family of an employee. After graduating with honors from high school, A.S. Mozzhukhin became a student at the Kuibyshev Military Medical Academy and completed his medical education with honors at the military faculty of the 2nd Moscow Medical Institute. In 1943, A.S. Mozzhukhin came to the Department of Normal Physiology of S.M. Kirov Military Medical Academy, with whom he connected more than 30 years of his life and in which he went from adjunct to head of the department, and scientific secretary of the academic council of the academy. The scientific activity of A.S. Mozzhukhin began in the life-giving atmosphere, which was formed at the department during the leadership of Academician L.A. Orbeli and his closest assistant A.V. Lebedinsky. All scientific activity of A.S. Mozzhukhin is an organic and natural combination of fundamental problems, physiology, psychophysiology, human biology, and practical medicine. The main scientific direction of the Department of Normal Physiology under the leadership of A.S. Mozzhukhin was on the study of the interaction of afferent systems under exposure to extreme stimuli as well as on the study of human functional reserves. In addition, a team examined the physiological cost of pedagogical activity depending on the age, seniority, psychophysical characteristics of teachers, and type of training sessions. A.S. Mozzhukhin investigated the biological effects of ionizing radiation. Together with chemist F.Yu. Rachinsky, he created a radio defense drug RS-1 and became a leading Soviet radiobiologist. A.S. Mozzhukhin created a unique scientific physiological school of the S.M. Kirov Military Medical Academy, which scientifically proved that the adaptation process was accompanied by the formation and improvement of a specific system of functional reserves for body adaptation, and the systemic factor was the result of the activity (adaptation). A.S. Mozzhukhin, while working at P.F. Lesgaft Institute of Physical Culture, proved that functional reserves have potentials in changing the functional activity of structural elements of the body and their interaction among themselves to achieve the target result, adapt to physical and psychoemotional loads, as well as the effect of various factors of the external environment on the body. The bright memory of Alexander Sergeyevich Mozzhukhin will forever remain in the hearts of his students and followers.
50
Fatimah, Is, Dwiarso Rubiyanto, and Thorikul Huda. "Preparation and Characterization of Ni/Zr-Saponite as Catalyst in Catalytic Hydrogen Transfer Reaction of Isopulegol." Materials Science Forum 827 (August 2015): 311–16. http://dx.doi.org/10.4028/www.scientific.net/msf.827.311.
Texto completo da fonteResumo:
World demand on menthol is so high and it is also a chalenge for organic synthetic chemist to develop new method of synthesis and conversion from another sources. Tandem cyclization-hydrogenation reaction towards citronellal is one important mechanism recently. Within the mechanism, hydrogenation of isopulegol is rate determining step. Considering green chemistry principles, this research deals with the use of heterogeneous catalyst in hydrogenation, Nickel (Ni) and also the use of microwave assisted organic synthesis method. An effort to improve activity and reusability of nickel in the reaction was conducted by dispersion in pillared clay materials, Ni-saponite.Nickel immobilized zirconia pillared saponite (Ni/Zr-Saponite) was prepared using pillarization-impregnation method. The composite, Zr-Saponite and Saponite were characterised by Scanning Electron Microscopy-energy dispersive x-ray (SEM-EDX), x-ray diffraction (XRD), surface acidity and surface area parameter based on nitrogen adsorption-desorption method. Catalytic hydrogen transfer of isopulegol hydrogenation was used as reaction model to show the comparison of catalytic activity.The XRD and SEM-EDX results of the composite indicate that zirconia was successfully distributed as pillar and nickel was dispersed within the pillared material. Both modifications increased the specific surface area, pore volume and surface acidity as a result of pillar formation and homogeneous distribution of the particles. Compared to raw saponite and Zr-Saponite, the composite exhibits significant improvement on total conversion of isopulegol. The presence of nickel affect the hydrogenation mechanism as showed by the product of menthol by catalytic hydrogen transfer.