Journal articles: 'Applications en catalyse'

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Boudart, Michel. "La catalyse et ses applications." Bulletin de la Classe des sciences 73, no. 1 (1987): 303–8. http://dx.doi.org/10.3406/barb.1987.57688.

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Robinson, Peter K. "Enzymes: principles and biotechnological applications." Essays in Biochemistry 59 (October 26, 2015): 1–41. http://dx.doi.org/10.1042/bse0590001.

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Enzymes are biological catalysts (also known as biocatalysts) that speed up biochemical reactions in living organisms, and which can be extracted from cells and then used to catalyse a wide range of commercially important processes. This chapter covers the basic principles of enzymology, such as classification, structure, kinetics and inhibition, and also provides an overview of industrial applications. In addition, techniques for the purification of enzymes are discussed.

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Mutti, Francesco G. "Alkene Cleavage Catalysed by Heme and Nonheme Enzymes: Reaction Mechanisms and Biocatalytic Applications." Bioinorganic Chemistry and Applications 2012 (2012): 1–13. http://dx.doi.org/10.1155/2012/626909.

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The oxidative cleavage of alkenes is classically performed by chemical methods, although they display several drawbacks. Ozonolysis requires harsh conditions (−78°C, for a safe process) and reducing reagents in a molar amount, whereas the use of poisonous heavy metals such as Cr, Os, or Ru as catalysts is additionally plagued by low yield and selectivity. Conversely, heme and nonheme enzymes can catalyse the oxidative alkene cleavage at ambient temperature and atmospheric pressure in an aqueous buffer, showing excellent chemo- and regioselectivities in certain cases. This paper focuses on the alkene cleavage catalysed by iron cofactor-dependent enzymes encompassing the reaction mechanisms (in case where it is known) and the application of these enzymes in biocatalysis.

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Lucas, Amand A. "Le confinement physique en catalyse hétérogène et autres applications." Bulletin de la Classe des sciences 19, no. 1 (2008): 219–28. http://dx.doi.org/10.3406/barb.2008.28667.

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Choi, Won Joon, Sungkyu Choi, Kei Ohkubo, Shunichi Fukuzumi, Eun Jin Cho, and Youngmin You. "Mechanisms and applications of cyclometalated Pt(ii) complexes in photoredox catalytic trifluoromethylation." Chemical Science 6, no. 2 (2015): 1454–64. http://dx.doi.org/10.1039/c4sc02537g.

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Fürstner, Alois. "Quelques commentaires sur la catalyse : la recherche fondamentale précède les applications." Comptes Rendus Chimie 17, no. 11 (November 2014): 1065–70. http://dx.doi.org/10.1016/j.crci.2014.06.003.

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Folcher, G. "Composés organométalliques des actinides: synthèses et applications à la catalyse homogène." Journal of the Less Common Metals 122 (August 1986): 139–51. http://dx.doi.org/10.1016/0022-5088(86)90402-9.

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Li, He, Xiao Feng, Pengpeng Shao, Jian Chen, Chunzhi Li, Sanjeevi Jayakumar, and Qihua Yang. "Synthesis of covalent organic frameworks via in situ salen skeleton formation for catalytic applications." Journal of Materials Chemistry A 7, no. 10 (2019): 5482–92. http://dx.doi.org/10.1039/c8ta11058a.

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A facile synthesis of COF-salen via in situ salen skeleton formation under air atmosphere is described herein. COF-salen–M prepared via metal ion coordination could efficiently catalyse chemical reactions, e.g. styrene epoxidation, epoxide hydration and cycloaddition reactions of epoxides with CO₂. More interestingly, both cooperation and isolation effects were observed in COF-salen–M.

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Kumar, Satyendra, Fariha Saleem, Manish Kumar Mishra, and Ajai K. Singh. "Oxine based unsymmetrical (O−, N, S/Se) pincer ligands and their palladium(ii) complexes: synthesis, structural aspects and applications as a catalyst in amine and copper-free Sonogashira coupling." New Journal of Chemistry 41, no. 7 (2017): 2745–55. http://dx.doi.org/10.1039/c7nj00067g.

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Mann, Greg, and Frédéric V. Stanger. "A Bio-logical Approach to Catalysis in the Pharmaceutical Industry." CHIMIA International Journal for Chemistry 74, no. 5 (May 27, 2020): 407–17. http://dx.doi.org/10.2533/chimia.2020.407.

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Enzymes have the potential to catalyse complex chemical reactions with unprecedented selectivity, under mild conditions in aqueous media. Accordingly, there is serious interest from the pharmaceutical industry to utilize enzymes as biocatalysts to produce medicines in an environmentally sustainable and economic manner. Prominent advances in the field of biotechnology have transformed this potential into a reality. Using modern protein engineering techniques, in a matter of months it is possible to evolve an enzyme, which fits the demands of a chemical process, or even to catalyse entirely novel chemistry. Consequently, biocatalysis is routinely applied throughout the pharmaceutical industry for a variety of applications, ranging from the manufacture of large volumes of high value blockbuster drugs to expanding the chemical space available for drug discovery.

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Álvarez, Roberto, Jordi Torres, Garazi Artola, Gorka Epelde, Sara Arranz, and Gerard Marrugat. "OBINTER: A Holistic Approach to Catalyse the Self-Management of Chronic Obesity." Sensors 20, no. 18 (September 6, 2020): 5060. http://dx.doi.org/10.3390/s20185060.

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Obesity is a preventable chronic condition that, in 2016, affected more than 1.9 billion people globally. Several factors have been identified that have a positive impact on long-term weight loss programs such as personalized recommendations, adherence strategies, weight and diet follow-up or physical activity tracking. Recently, various applications have been developed which help patients to self-manage their condition. These apps implement either one or some of these identified factors; however, there is not a single application that combines all of them following a holistic approach. In this context, we developed the OBINTER platform, which assists patients during the weight loss process by targeting user engagement during the longer term. The solution includes a mobile application which allows users to fill out dietetic questionnaires, receive dietetic and nutraceutical plans, track the evolution of their weight and adherence to the diet, as well as track their physical activity via a wearable device. Furthermore, an adherence strategy has been developed as a tool to foster the app usage during the whole weight loss process. In this paper, we present how the OBINTER approach gathers all of these features as well as the positive results of a usability testing study performed to assess the performance and usability of the OBINTER platform.

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Miralles-Robledillo, Jose María, Javier Torregrosa-Crespo, Rosa María Martínez-Espinosa, and Carmen Pire. "DMSO Reductase Family: Phylogenetics and Applications of Extremophiles." International Journal of Molecular Sciences 20, no. 13 (July 8, 2019): 3349. http://dx.doi.org/10.3390/ijms20133349.

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Dimethyl sulfoxide reductases (DMSO) are molybdoenzymes widespread in all domains of life. They catalyse not only redox reactions, but also hydroxylation/hydration and oxygen transfer processes. Although literature on DMSO is abundant, the biological significance of these enzymes in anaerobic respiration and the molecular mechanisms beyond the expression of genes coding for them are still scarce. In this review, a deep revision of the literature reported on DMSO as well as the use of bioinformatics tools and free software has been developed in order to highlight the relevance of DMSO reductases on anaerobic processes connected to different biogeochemical cycles. Special emphasis has been addressed to DMSO from extremophilic organisms and their role in nitrogen cycle. Besides, an updated overview of phylogeny of DMSOs as well as potential applications of some DMSO reductases on bioremediation approaches are also described.

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Heuts, J. P. A., G. E. Roberts, and J. D. Biasutti. "Catalytic Chain Transfer Polymerization: an Overview." Australian Journal of Chemistry 55, no. 7 (2002): 381. http://dx.doi.org/10.1071/ch02098.

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Catalytic chain transfer polymerization is a very efficient and versatile free-radical polymerization technique for the synthesis of functional macromonomers. The process is based on the ability of certain transition metal complexes, most notably of low-spin CoII complexes such as cobaloximes, to catalyse the chain transfer to monomer reaction. A brief overview is given of the applications and the mechanistic understanding of catalytic chain transfer polymerization.

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Proietti, Giordano, Yali Wang, Chiara Punzo, and Jasmin Mecinović. "Substrate Scope for Human Histone Lysine Acetyltransferase KAT8." International Journal of Molecular Sciences 22, no. 2 (January 15, 2021): 846. http://dx.doi.org/10.3390/ijms22020846.

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Biomedically important histone lysine acetyltransferase KAT8 catalyses the acetyl coenzyme A-dependent acetylation of lysine on histone and other proteins. Here, we explore the ability of human KAT8 to catalyse the acetylation of histone H4 peptides possessing lysine and its analogues at position 16 (H4K16). Our synthetic and enzymatic studies on chemically and structurally diverse lysine mimics demonstrate that KAT8 also has a capacity to acetylate selected lysine analogues that possess subtle changes on the side chain and main chain. Overall, this work highlights that KAT8 has a broader substrate scope beyond natural lysine, and contributes to the design of new chemical probes targeting KAT8 and other members of the histone lysine acetyltransferase (KAT) family.

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Zhang, Huijie, Rosa Catania, and Lars J. C. Jeuken. "Membrane Protein Modified Electrodes in Bioelectrocatalysis." Catalysts 10, no. 12 (December 6, 2020): 1427. http://dx.doi.org/10.3390/catal10121427.

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Transmembrane proteins involved in metabolic redox reactions and photosynthesis catalyse a plethora of key energy-conversion processes and are thus of great interest for bioelectrocatalysis-based applications. The development of membrane protein modified electrodes has made it possible to efficiently exchange electrons between proteins and electrodes, allowing mechanistic studies and potentially applications in biofuels generation and energy conversion. Here, we summarise the most common electrode modification and their characterisation techniques for membrane proteins involved in biofuels conversion and semi-artificial photosynthesis. We discuss the challenges of applications of membrane protein modified electrodes for bioelectrocatalysis and comment on emerging methods and future directions, including recent advances in membrane protein reconstitution strategies and the development of microbial electrosynthesis and whole-cell semi-artificial photosynthesis.

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Takahashi, F., Z. R. Sun, K. Fukushi, Y. Oshima, and K. Yamamoto. "Enhanced removal of sodium salts supported by in-situ catalyst synthesis in a supercritical water oxidation process." Water Science and Technology 65, no. 11 (June 1, 2012): 2034–41. http://dx.doi.org/10.2166/wst.2012.109.

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For practical applications of supercritical water oxidation to wastewater treatment, the deposition of inorganic salts in supercritical phase must be controlled to prevent a reactor from clogging. This study investigated enhanced removal of sodium salts with titanium particles, serving as a salt trapper and a catalyst precursor, and sodium recovery by sub-critical water. When Na2CO3 was tested as a model salt, sodium removal efficiency was higher than theoretically maximum efficiency defined by Na2CO3 solubility. The enhanced sodium removal resulted from in-situ synthesis of sodium titanate, which could catalyse acetic acid oxidation. The kinetics of sodium removal was described well by a diffusion mass-transfer model combined with a power law-type rate model of sodium titanate synthesis. Titanium particles showed positive effect on sodium removal in the case of NaOH, Na2SO4 and Na3PO4. However, they had negligible effect for NaCl and negative effect for Na2CrO4, respectively. More than 99% of trapped sodium was recovered by sub-critical water except for Na2CrO4. In contrast, sodium recovery efficiency remained less than 50% in the case of Na2CrO4. Reused titanium particles showed the same performance for enhanced sodium removal. Enhanced salt removal supported by in-situ catalyst synthesis has great potential to enable both salt removal control and catalytic oxidation.

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Mojsov, Kiro, Aco Janevski, Darko Andronikov, Sonja Jordeva, Saška Golomeova, Stevan Gaber, and Ivan Ignjatov. "Production and application of glucose oxidase enzyme in textile technology." Tekstilna industrija 69, no. 1 (2021): 21–27. http://dx.doi.org/10.5937/tekstind2101021m.

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Biotechnology is an ecological advantageous and moreover economically beneficial technology. The most established application of biotechnology in textiles has been in the field of enzymatic pretreatment. Glucose oxidase (GOD) catalyse the oxidation of b-D-glucose into gluconic acid by utilizing molecular oxygen as an electron acceptor with a simultaneous production of hydrogen peroxide (HP). Glucose oxidases are commercially gaining a lot of attention in textile technology. In an enzymatic pretreatment, the textile substrate is less damaged when compared to a classical pretreatment. Enzymatic pre-treatments of cellulose fabrics often save large amounts of raw materials, chemicals, energy and water. Bleaching with glucose oxidase thus represents an economic and ecological potential when compared to the classical process with added hydrogen peroxide. This review represents the basic properties and production of glucose oxidases and their applications in textile technology.

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Das, Debasis, and Jian Hong. "Irreversible Kinase Inhibitors Targeting Cysteine Residues and their Applications in Cancer Therapy." Mini-Reviews in Medicinal Chemistry 20, no. 17 (November 18, 2020): 1732–53. http://dx.doi.org/10.2174/1389557520666200513121524.

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Protein kinases are conserved enzymes that catalyse the phosphorylation process in cells. They are recognized as the targets for many diseases. The FDA has approved many kinase inhibitors for the treatment of cancer and confirmed kinases as relevant targets for drug discovery. Major approved drugs are ATP competitive reversible non-covalent inhibitors that achieve selectivity by recognition of specific binding pockets of targeted kinases. In recent years, scientists have paid attention on developing irreversible covalent kinase inhibitors to achieve better selectivity, less toxicity and side effects. Since 2013, seven Irreversible Kinase Inhibitors (IKIs), including; afatinib, ibrutinib, neratinib, dacomitinib, osimertinib, acalabrutinib and zanubrutinib have been approved by the FDA for treatment of severe diseases, like; Metastatic Non-Small Cell Lung Cancer (NSCLC), Mantle Cell Lymphoma (MCL) and HER2-positive breast cancer. These inhibitors target the cysteine residues of kinases. Many IKIs that target cysteine residues are in clinical trials for different diseases and are yet to be approved. We have reviewed the research done and efforts made for finding novel cysteine targeted IKIs as drugs in the recent years.

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Chambers, Cecilia R., and Wayne M. Patrick. "Archaeal Nucleic Acid Ligases and Their Potential in Biotechnology." Archaea 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/170571.

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With their ability to catalyse the formation of phosphodiester linkages, DNA ligases and RNA ligases are essential tools for many protocols in molecular biology and biotechnology. Currently, the nucleic acid ligases from bacteriophage T4 are used extensively in these protocols. In this review, we argue that the nucleic acid ligases from Archaea represent a largely untapped pool of enzymes with diverse and potentially favourable properties for new and emerging biotechnological applications. We summarise the current state of knowledge on archaeal DNA and RNA ligases, which makes apparent the relative scarcity of information onin vitroactivities that are of most relevance to biotechnologists (such as the ability to join blunt- or cohesive-ended, double-stranded DNA fragments). We highlight the existing biotechnological applications of archaeal DNA ligases and RNA ligases. Finally, we draw attention to recent experiments in which protein engineering was used to modify the activities of the DNA ligase fromPyrococcus furiosusand the RNA ligase fromMethanothermobacter thermautotrophicus, thus demonstrating the potential for further work in this area.

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Cammack, Richard. "Iron–sulfur proteins." Biochemist 34, no. 5 (October 1, 2012): 14–17. http://dx.doi.org/10.1042/bio03405014.

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Iron makes up 35% of the Earth's mass, and is plentiful in its crust (approximately 5%), so it is not surprising that Biology has found many different applications for it. Iron–sulfur (Fe–S) clusters are essential, ubiquitous inorganic cofactors in electron-transport proteins of respiration and photosynthesis, and are responsible for the activity of hundreds of enzymes1. Various types of clusters (Figure 1) occur in iron-sulfur proteins, bound covalently to protein ligands, usually cysteine sulfur. Their activity is not confined to oxidation/reduction; in enzymes such as aconitase, they are involved in substrate binding and conversion. Fe–S enzymes that catalyse difficult reactions, such as nitrogenase in nitrogen fixation and hydrogenase in hydrogen production, contain complex ‘superclusters’2.

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Brignole, Edward J., Nozomi Ando, Christina M. Zimanyi, and Catherine L. Drennan. "The prototypic class Ia ribonucleotide reductase from Escherichia coli: still surprising after all these years." Biochemical Society Transactions 40, no. 3 (May 22, 2012): 523–30. http://dx.doi.org/10.1042/bst20120081.

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RNRs (ribonucleotide reductases) are key players in nucleic acid metabolism, converting ribonucleotides into deoxyribonucleotides. As such, they maintain the intracellular balance of deoxyribonucleotides to ensure the fidelity of DNA replication and repair. The best-studied RNR is the class Ia enzyme from Escherichia coli, which employs two subunits to catalyse its radical-based reaction: β2 houses the diferric-tyrosyl radical cofactor, and α2 contains the active site. Recent applications of biophysical methods to the study of this RNR have revealed the importance of oligomeric state to overall enzyme activity and suggest that unprecedented subunit configurations are in play. Although it has been five decades since the isolation of nucleotide reductase activity in extracts of E. coli, this prototypical RNR continues to surprise us after all these years.

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Bheemanaik, Shivakumara, Yeturu V. R. Reddy, and Desirazu N. Rao. "Structure, function and mechanism of exocyclic DNA methyltransferases." Biochemical Journal 399, no. 2 (September 27, 2006): 177–90. http://dx.doi.org/10.1042/bj20060854.

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DNA MTases (methyltransferases) catalyse the transfer of methyl groups to DNA from AdoMet (S-adenosyl-L-methionine) producing AdoHcy (S-adenosyl-L-homocysteine) and methylated DNA. The C5 and N4 positions of cytosine and N6 position of adenine are the target sites for methylation. All three methylation patterns are found in prokaryotes, whereas cytosine at the C5 position is the only methylation reaction that is known to occur in eukaryotes. In general, MTases are two-domain proteins comprising one large and one small domain with the DNA-binding cleft located at the domain interface. The striking feature of all the structurally characterized DNA MTases is that they share a common core structure referred to as an ‘AdoMet-dependent MTase fold’. DNA methylation has been reported to be essential for bacterial virulence, and it has been suggested that DNA adenine MTases (Dams) could be potential targets for both vaccines and antimicrobials. Drugs that block Dam could slow down bacterial growth and therefore drug-design initiatives could result in a whole new generation of antibiotics. The transfer of larger chemical entities in a MTase-catalysed reaction has been reported and this represents an interesting challenge for bio-organic chemists. In general, amino MTases could therefore be used as delivery systems for fluorescent or other reporter groups on to DNA. This is one of the potential applications of DNA MTases towards developing non-radioactive DNA probes and these could have interesting applications in molecular biology. Being nucleotide-sequence-specific, DNA MTases provide excellent model systems for studies on protein–DNA interactions. The focus of this review is on the chemistry, enzymology and structural aspects of exocyclic amino MTases.

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Hell, Zoltán, Ágnes Magyar, and Kinga Juhász. "The Application of 4Å Molecular Sieves in Organic Chemical Syntheses: An Overview." Synthesis 53, no. 02 (October 22, 2020): 279–95. http://dx.doi.org/10.1055/s-0040-1706535.

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AbstractIn the last two decades, considerable attention has been devoted to the use of 4Å molecular sieves (MS 4A) in organic chemical syntheses. Initially, they were applied as drying agents in order to dry gases, solvents and liquid reagents. Nowadays, there is a growing tendency to apply MS 4A as an additive, catalyst, co-catalyst or catalyst support in organic reactions. In this review, we aim to summarize the recent examples of organic syntheses promoted by MS 4A from 1997 to 2020. We hope to provide the reader with an overview of the potential of MS 4A in the field of organic synthesis.1 Introduction2 Application as an Additive3 Application as Catalyst4 Application as Co-catalyst5 Application as Support6 Conclusion

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Ahroni, Y., N. Dresler, A. Ulanov, D. Ashkenazi, M. Aviv, M. Librus, and A. Stern. "Selected Applications of Stimuli-Responsive Polymers: 4D Printing by the Fused Filament Fabrication Technology." Annals of Dunarea de Jos University of Galati Fascicle XII Welding Equipment and Technology 31 (December 28, 2020): 13–22. http://dx.doi.org/10.35219/awet.2020.02.

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In the past few years four-dimensional (4D) printing technologies have attained worldwide interest and they are now considered the "next big thing". The aim of this research is to provide three selected examples of stimuli-responsive polymer (SRP) applications additively manufactured (AM) by the fused filament fabrication (FFF) technique. To that end, a CCT BLUE filament of thermo-responsive polymer was chosen to produce a water temperature indicator, which changes colour from blue to white when temperature increases; a CCU RED filament of photo-responsive polymer was used to produce a sunlight / UV indicator bracelet; a transparent PLA CLEAR polymer, a CCU RED photo-responsive polymer, and an electrical conductive PLA polymer were selected to produce a smart business card stand. The temperature indicator capability was analysed based on examining colour changes as a function of temperature changes. The sunlight/UV indicator capability was analysed based on the inspection of colour change as a function of absorbed sun/ultraviolet light. The electrical conductivity of the conductive PLA polymer was examined by performing resistance measurements. All three objects were successfully produced and their functionality was demonstrated. We hope that these examples will catalyse the expansion of FFF 4D printed SRP applications, as much work remains to be done in designing the parts and developing FFF printing parameters that take advantage of the stimuli-responsive materials currently being developed for FFF technology.

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Gomes, Clarissa P. C., David de Gonzalo-Calvo, Rocio Toro, Tiago Fernandes, Daniel Theisen, Da-Zhi Wang, and Yvan Devaux. "Non-coding RNAs and exercise: pathophysiological role and clinical application in the cardiovascular system." Clinical Science 132, no. 9 (May 21, 2018): 925–42. http://dx.doi.org/10.1042/cs20171463.

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There is overwhelming evidence that regular exercise training is protective against cardiovascular disease (CVD), the main cause of death worldwide. Despite the benefits of exercise, the intricacies of their underlying molecular mechanisms remain largely unknown. Non-coding RNAs (ncRNAs) have been recognized as a major regulatory network governing gene expression in several physiological processes and appeared as pivotal modulators in a myriad of cardiovascular processes under physiological and pathological conditions. However, little is known about ncRNA expression and role in response to exercise. Revealing the molecular components and mechanisms of the link between exercise and health outcomes will catalyse discoveries of new biomarkers and therapeutic targets. Here we review the current understanding of the ncRNA role in exercise-induced adaptations focused on the cardiovascular system and address their potential role in clinical applications for CVD. Finally, considerations and perspectives for future studies will be proposed.

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Bogue, Robert. "Flexible and soft robotic grippers: the key to new markets?" Industrial Robot: An International Journal 43, no. 3 (May 16, 2016): 258–63. http://dx.doi.org/10.1108/ir-01-2016-0027.

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Purpose This paper aims to provide details of recent commercial and academic developments in flexible and soft grippers and considers their impact on emerging robotic markets. Design/methodology/approach Following an introduction, this paper first considers commercially available anthropomorphic robotic hands and soft grippers. It then discusses a selection of recent research activities and concludes with a brief discussion of the potential of these developments. Findings Anthropomorphic robotic hands, which seek to mimic the structure and capabilities of the human hand, together with a technologically diverse family of soft grippers have recently have been commercialised. Most are produced by companies which spun-out from academic establishments. A strong body of innovative research continues and involves a wide range of principles and technologies. These gripping technologies are expected to catalyse several new and emerging applications; the most important being in agile manufacturing, particularly when used with collaborative robots (cobots). Originality/value This paper provides details of recent developments and research into anthropomorphic hands and soft grippers and an insight into their applications.

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Ipsen, Johan Ø., Magnus Hallas-Møller, Søren Brander, Leila Lo Leggio, and Katja S. Johansen. "Lytic polysaccharide monooxygenases and other histidine-brace copper proteins: structure, oxygen activation and biotechnological applications." Biochemical Society Transactions 49, no. 1 (January 15, 2021): 531–40. http://dx.doi.org/10.1042/bst20201031.

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Lytic polysaccharide monooxygenases (LPMOs) are mononuclear copper enzymes that catalyse the oxidative cleavage of glycosidic bonds. They are characterised by two histidine residues that coordinate copper in a configuration termed the Cu-histidine brace. Although first identified in bacteria and fungi, LPMOs have since been found in all biological kingdoms. LPMOs are now included in commercial enzyme cocktails used in industrial biorefineries. This has led to increased process yield due to the synergistic action of LPMOs with glycoside hydrolases. However, the introduction of LPMOs makes control of the enzymatic step in industrial stirred-tank reactors more challenging, and the operational stability of the enzymes is reduced. It is clear that much is still to be learned about the interaction between LPMOs and their complex natural and industrial environments, and fundamental scientific studies are required towards this end. Several atomic-resolution structures have been solved providing detailed information on the Cu-coordination sphere and the interaction with the polysaccharide substrate. However, the molecular mechanisms of LPMOs are still the subject of intense investigation; the key question being how the proteinaceous environment controls the copper cofactor towards the activation of the O-O bond in O2 and cleavage of the glycosidic bonds in polysaccharides. The need for biochemical characterisation of each putative LPMO is discussed based on recent reports showing that not all proteins with a Cu-histidine brace are enzymes.

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Zaidi, Kamal Uddin, Ayesha S. Ali, Sharique A. Ali, and Ishrat Naaz. "Microbial Tyrosinases: Promising Enzymes for Pharmaceutical, Food Bioprocessing, and Environmental Industry." Biochemistry Research International 2014 (2014): 1–16. http://dx.doi.org/10.1155/2014/854687.

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Tyrosinase is a natural enzyme and is often purified to only a low degree and it is involved in a variety of functions which mainly catalyse theo-hydroxylation of monophenols into their correspondingo-diphenols and the oxidation ofo-diphenols too-quinones using molecular oxygen, which then polymerizes to form brown or black pigments. The synthesis ofo-diphenols is a potentially valuable catalytic ability and thus tyrosinase has attracted a lot of attention with respect to industrial applications. In environmental technology it is used for the detoxification of phenol-containing wastewaters and contaminated soils, as biosensors for phenol monitoring, and for the production of L-DOPA in pharmaceutical industries, and is also used in cosmetic and food industries as important catalytic enzyme. Melanin pigment synthesized by tyrosinase has found applications for protection against radiation cation exchangers, drug carriers, antioxidants, antiviral agents, or immunogen. The recombinantV. spinosumtryosinase protein can be used to produce tailor-made melanin and other polyphenolic materials using various phenols and catechols as starting materials. This review compiles the recent data on biochemical and molecular properties of microbial tyrosinases, underlining their importance in the industrial use of these enzymes. After that, their most promising applications in pharmaceutical, food processing, and environmental fields are presented.

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Wallrodt, Sarah, Edward L. Simpson, and Andreas Marx. "Investigation of the action of poly(ADP-ribose)-synthesising enzymes on NAD+ analogues." Beilstein Journal of Organic Chemistry 13 (March 10, 2017): 495–501. http://dx.doi.org/10.3762/bjoc.13.49.

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ADP-ribosyl transferases with diphtheria toxin homology (ARTDs) catalyse the covalent addition of ADP-ribose onto different acceptors forming mono- or poly(ADP-ribos)ylated proteins. Out of the 18 members identified, only four are known to synthesise the complex poly(ADP-ribose) biopolymer. The investigation of this posttranslational modification is important due to its involvement in cancer and other diseases. Lately, metabolic labelling approaches comprising different reporter-modified NAD+ building blocks have stimulated and enriched proteomic studies and imaging applications of ADP-ribosylation processes. Herein, we compare the substrate scope and applicability of different NAD+ analogues for the investigation of the polymer-synthesising enzymes ARTD1, ARTD2, ARTD5 and ARTD6. By varying the site and size of the NAD+ modification, suitable probes were identified for each enzyme. This report provides guidelines for choosing analogues for studying poly(ADP-ribose)-synthesising enzymes.

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Morón, Carlos, Alfonso Garcia, Enrique Tremps, and Jose Andrés Somolinos. "Building Functional Surfaces for Biosensors Development." Key Engineering Materials 543 (March 2013): 204–7. http://dx.doi.org/10.4028/www.scientific.net/kem.543.204.

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Polyelectrolyte multilayers (PEM) built by layer-by-layer technique have been extensively studied over the last years, resulting in a wide variety of current and potential applications. This technique can be used to construct thin films with different functionalities, or to functionalize surfaces with substantial different properties of those of the underlying substrates. The multilayering process is achieved by the alternate adsorption of oppositely charged polyelectrolytes. In this work we get advantage of the protein resistant property of the Poly (l-lysine)-graft-(polyethyleneglycol) to create protein patterns. Proteins can be immobilized on a surface by unspecific physical adsorption, covalent binding or through specific interactions. The first protein used in this work was laccase, a copper-containing redox enzyme that catalyse the oxidation of a broad range of polyphenols and aromatic substrates, coupled to the reduction of O2to H2O without need of cofactors. Applications of laccases have been reported in food, pulp, paper, and textile industry, and also in biosensor development. Some uses require the immobilization of the enzyme on solid supports by adsorption, covalent attachment, entrapment, etc, on several substrates. Especially for biosensor development, highly active, stable and reproducible immobilization of laccase is required.

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Wang, Rui, Jiaquan Wu, David Kin Jin, Yali Chen, Zhijia Lv, Qian Chen, Qiwei Miao, Xiaoyu Huo, and Feng Wang. "Structure of NADP+-bound 7β-hydroxysteroid dehydrogenase reveals two cofactor-binding modes." Acta Crystallographica Section F Structural Biology Communications 73, no. 5 (April 26, 2017): 246–52. http://dx.doi.org/10.1107/s2053230x17004460.

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In mammals, bile acids/salts and their glycine and taurine conjugates are effectively recycled through enterohepatic circulation. 7β-Hydroxysteroid dehydrogenases (7β-HSDHs; EC 1.1.1.201), including that from the intestinal microbeCollinsella aerofaciens, catalyse the NADPH-dependent reversible oxidation of secondary bile-acid products to avoid potential toxicity. Here, the first structure of NADP+bound to dimeric 7β-HSDH is presented. In one active site, NADP+adopts a conventional binding mode similar to that displayed in related enzyme structures. However, in the other active site a unique binding mode is observed in which the orientation of the nicotinamide is different. Since 7β-HSDH has become an attractive target owing to the wide and important pharmaceutical use of its product ursodeoxycholic acid, this work provides a more detailed template to support rational protein engineering to improve the enzymatic activities of this useful biocatalyst, further improving the yield of ursodeoxycholic acid and its other applications.

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Qiu, Jane. "Qi Zhou: the coming of age in China's stem-cell research and regenerative medicine." National Science Review 4, no. 4 (June 24, 2017): 550–52. http://dx.doi.org/10.1093/nsr/nwx068.

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Abstract Between 2011 and 2015, China invested about 3 billion yuan (US$435 million) on stem-cell research and regenerative medicine. This has led to major scientific breakthroughs, solidifying the country's role as a global leader in this field. Last September, China launched another major programm called Stem Cells and Transfer Research — with a similar budget over five years but focusing more on clinical applications. Many see this as a golden opportunity to catalyse significant medical advances, providing relief for patients with conditions such as Parkinson's Disease and macular degeneration. NSR recently talked to Qi Zhou, a leading stem-cell researcher at CAS’s Institute of Zoology in Beijing, about recent research progress, China's challenges and opportunities, how the government is trying to tighten the regulation and why we must move forward cautiously when applying new technologies, such as gene editing and mitochondria replacement therapy, in a clinical setting.

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Franceus, Jorick, and Tom Desmet. "Sucrose Phosphorylase and Related Enzymes in Glycoside Hydrolase Family 13: Discovery, Application and Engineering." International Journal of Molecular Sciences 21, no. 7 (April 5, 2020): 2526. http://dx.doi.org/10.3390/ijms21072526.

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Sucrose phosphorylases are carbohydrate-active enzymes with outstanding potential for the biocatalytic conversion of common table sugar into products with attractive properties. They belong to the glycoside hydrolase family GH13, where they are found in subfamily 18. In bacteria, these enzymes catalyse the phosphorolysis of sucrose to yield α-glucose 1-phosphate and fructose. However, sucrose phosphorylases can also be applied as versatile transglucosylases for the synthesis of valuable glycosides and sugars because their broad promiscuity allows them to transfer the glucosyl group of sucrose to a diverse collection of compounds other than phosphate. Numerous process and enzyme engineering studies have expanded the range of possible applications of sucrose phosphorylases ever further. Moreover, it has recently been discovered that family GH13 also contains a few novel phosphorylases that are specialised in the phosphorolysis of sucrose 6F-phosphate, glucosylglycerol or glucosylglycerate. In this review, we provide an overview of the progress that has been made in our understanding and exploitation of sucrose phosphorylases and related enzymes over the past ten years.

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Adeoye, Raphael I., Dunsin S. Osalaye, Theresia K. Ralebitso-Senior, Amanda Boddis, Amanda J. Reid, Amos A. Fatokun, Andrew K. Powell, Sylvia O. Malomo, and Femi J. Olorunniji. "Catalytic Activities of Multimeric G-Quadruplex DNAzymes." Catalysts 9, no. 7 (July 19, 2019): 613. http://dx.doi.org/10.3390/catal9070613.

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G-quadruplex DNAzymes are short DNA aptamers with repeating G4 quartets bound in a non-covalent complex with hemin. These G4/Hemin structures exhibit versatile peroxidase-like catalytic activity with a wide range of potential applications in biosensing and biotechnology. Current efforts are aimed at gaining a better understanding of the molecular mechanism of DNAzyme catalysis as well as devising strategies for improving their catalytic efficiency. Multimerisation of discrete units of G-quadruplexes to form multivalent DNAzyes is an emerging design strategy aimed at enhancing the peroxidase activities of DNAzymes. While this approach holds promise of generating more active multivalent G-quadruplex DNAzymes, few examples have been studied and it is not clear what factors determine the enhancement of catalytic activities of multimeric DNAzymes. In this study, we report the design and characterisation of multimers of five G-quadruplex sequences (AS1411, Bcl-2, c-MYC, PS5.M and PS2.M). Our results show that multimerisation of G-quadruplexes that form parallel structure (AS1411, Bcl-2, c-MYC) leads to significant rate enhancements characteristic of cooperative and/or synergistic interactions between the monomeric units. In contrast, multimerisation of DNA sequences that form non-parallel structures (PS5.M and PS2.M) did not exhibit similar levels of synergistic increase in activities. These results show that design of multivalent G4/Hemin structures could lead to a new set of versatile and efficient DNAzymes with enhanced capacity to catalyse peroxidase-mimic reactions.

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Dabhane, Harshal, Suresh Ghotekar, Pawan Tambade, Shreyas Pansambal, Rajeshwari Oza, and Vijay Medhane. "MgO nanoparticles: Synthesis, characterization, and applications as a catalyst for organic transformations." European Journal of Chemistry 12, no. 1 (March 31, 2021): 86–108. http://dx.doi.org/10.5155/eurjchem.12.1.86-108.2060.

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Currently, the size and shape selective synthesis of nanoparticles (NPs) and their varied catalytic applications are gaining significant enthusiasm in the field of nanochemistry. Homogeneous catalysis is crucial due to its inherent benefits like high selectivity and mild reaction conditions. Nevertheless, it endures with serious disadvantages of catalysts and/or product separation/recycles compared to their heterogeneous counterparts restricting their catalytic applications. The utilization of catalysts in the form of nano-size is an elective methodology for the combination of merits of homogeneous and heterogeneous catalysis. Magnesium oxide (MgO) NPs are important as they find applications for catalysis, organic transformation, and synthesis of fine chemicals and organic intermediates. The applications of MgO NPs in diverse organic transformations including oxidation, reduction, epoxidation, condensation, and C-C, C-N, C-O, C-S bond formation in a variety of notable heterocyclic reactions are also discussed. The use of MgO NPs in organic transformation is advantageous as it mitigates the use of ligands; the procurable separation of catalyst for recyclability makes the protocol heterogeneous and monetary. MgO NPs gave efficacious catalytic performance towards the desired products due to high surface area. By considering these efficient merits, scientists have focused their attentions towards stupendous applications of MgO NPs in selective organic transformation. In the current review article, we summarized the synthesis of MgO NPs and numerous characterization techniques, whereas the application section illustrates their utility as a catalyst in several organic transformations. We believe this decisive appraisal will provide imperative details to further advance the application of MgO NPs in selective catalysis.

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Leao, Lucia. "Plant Portraits: Creative processes, communication and the search for new paradigms1." Technoetic Arts 17, no. 1 (June 1, 2019): 57–70. http://dx.doi.org/10.1386/tear_00006_1.

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Abstract What can we learn from plants? Which forms of intelligence and knowledge can we discover by dedicating ourselves to understanding the life of a plant, its characteristics, interactions with the environment and cultural narratives? This article aims to bridge recent studies in plant intelligence, Semiotics and creative processes. Departing form the idea that the world arrived at a critical situation and the planet Earth cannot continue being exploited as an infinite source, we argue that it is necessary to promote transformations in our culture, abandoning the anthropocentric framework and looking for new perspectives. In this sense, connecting communication, art, science and education, the purpose of Plant Portraits is to create experiences and propitiate encounters that catalyse the awakening of an expanded and integrated consciousness.

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Burnat, Dariusz, Roman Kontic, Lorenz Holzer, Patrick Steiger, Davide Ferri, and Andre Heel. "Smart material concept: reversible microstructural self-regeneration for catalytic applications." Journal of Materials Chemistry A 4, no. 30 (2016): 11939–48. http://dx.doi.org/10.1039/c6ta03417a.

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This paper presents a proof-of-concept study and demonstrates the next generation of a “smart” catalyst material, applicable to high temperature catalysis and electro-catalysis such as gas processing and as a catalyst for solid oxide cells.

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Clerici, Mario G. "Zeolites for Fine Chemical Production State of Art and Perspectives." Eurasian Chemico-Technological Journal 3, no. 4 (July 10, 2017): 231. http://dx.doi.org/10.18321/ectj573.

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The paper analyses the role of catalysis and that of renewable resources in the frame of a sustainable development. The possible uses of natural feedstocks for chemical production and the application of catalytic<br />methods to their transformations are reviewed, with emphasis on carbohydrates and vegetable oils and on zeolite catalysts, respectively. The problems arising from the embedment of active sites on the catalyst<br />surface are discussed, with the aid of specific examples taken from oxidation and acid catalysed reactions.

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Abdul Hamza, Taha Mahdi. "Review on Applications of Nanocatalyst in Refineries and petrochemicals." Journal of Petroleum Research and Studies 7, no. 2 (May 6, 2021): 96–107. http://dx.doi.org/10.52716/jprs.v7i2.191.

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In the nanoscience where all the devices and technologies are going to smaller in size with improved properties, catalysis is an important field of application. In recent years, nanocatalysis has become more emerging field of science due to its high activity, selectivity and productivity. In this mini-review, we are trying to summarize data reported in literature for application of nano sized catalyst in Refineries and petrochemicals industries. By decreasing the size of the catalyst, advantages such as large surface area would be exposed to the reactant. Main applications of nanocatalysts in steam reforming, bio diesel production, and several other point of application are discussed here in detail.

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Bakonyi, Daniel, Christine Toelzer, Michael Stricker, Werner Hummel, Karsten Niefind, and Harald Gröger. "Expanding the Application Range of Microbial Oxidoreductases by an Alcohol Dehydrogenase from Comamonas testosteroni with a Broad Substrate Spectrum and pH Profile." Catalysts 10, no. 11 (November 4, 2020): 1281. http://dx.doi.org/10.3390/catal10111281.

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Alcohol dehydrogenases catalyse the conversion of a large variety of ketone substrates to the corresponding chiral products. Due to their high regio- and stereospecificity, they are key components in a wide range of industrial applications. A novel alcohol dehydrogenase from Comamonas testosteroni (CtADH) was identified in silico, recombinantly expressed and purified, enzymatically and biochemically investigated as well as structurally characterized. These studies revealed a broad pH profile and an extended substrate spectrum with the highest activity for compounds containing halogens as substituents and a moderate activity for bulky–bulky ketones. Biotransformations with selected ketones—performed with a coupled regeneration system for the co-substrate NADPH—resulted in conversions of more than 99% with all tested substrates and with excellent enantioselectivity for the corresponding S-alcohol products. CtADH/NADPH/substrate complexes modelled on the basis of crystal structures of CtADH and its closest homologue suggested preliminary hints to rationalize the enzyme’s substrate preferences

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Mao, Zhenjun, Haorui Gu, and Xufeng Lin. "Recent Advances of Pd/C-Catalyzed Reactions." Catalysts 11, no. 9 (September 7, 2021): 1078. http://dx.doi.org/10.3390/catal11091078.

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The Pd/C-catalyzed reactions, including reduction reactions and cross-coupling reactions, play an irreplaceable role in modern organic synthesis. Compared to the homogeneous palladium catalyst system, the heterogeneous Pd/C catalyst system offers an alternative protocol that has particular advantages and applications. Herein, a review on Pd/C-catalyzed reactions is presented. Both the advances in Pd/C-catalyzed methodologies and the application of Pd/C-catalysis in total synthesis are covered in this review.

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Der Derian, James, and Alexander Wendt. "‘Quantizing international relations’: The case for quantum approaches to international theory and security practice." Security Dialogue 51, no. 5 (February 5, 2020): 399–413. http://dx.doi.org/10.1177/0967010620901905.

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This special issue is conceived out of the proposition that recent developments in quantum theory as well as innovations in quantum technology have profound implications for international relations, especially in the field of international security. Interaction with quantum theory outside the circle of physics has been limited; our goal is to catalyse an informed debate on the virtues of quantum theory for international relations. As new scientific discoveries and technological applications suggest large-scale quantum phenomena, near-simultaneous interconnectivity creates global entanglements, and ubiquitous media produce profound observer-effects, we wish to make of quantum theory a human science. With the arrival of quantum computing, communications and artificial intelligence, we can also expect to see significant transformations in the nature, production and distribution of power and knowledge. This special issue introduces quantum approaches that can help us better understand, anticipate and perhaps even ameliorate the most pressing global issues facing us today and in the near future.

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Srivastava, Vishal, Pravin K. Singh, Arjita Srivastava, and Praveen P. Singh. "Synthetic applications of flavin photocatalysis: a review." RSC Advances 11, no. 23 (2021): 14251–59. http://dx.doi.org/10.1039/d1ra00925g.

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Lomic, Gizela, Erne Kis, Goran Boskovic, and Radmila Marinkovic-Neducin. "Application of scanning electron microscopy in catalysis." Acta Periodica Technologica, no. 35 (2004): 67–77. http://dx.doi.org/10.2298/apt0435067l.

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A short survey of various information obtained by scanning electron microscopy (SEM) in the investigation of heterogeneous catalysts and nano-structured materials have been presented. The capabilities of SEM analysis and its application in testing catalysts in different fields of heterogeneous catalysis are illustrated. The results encompass the proper way of catalyst preparation, the mechanism of catalyst active sites formation catalysts changes and catalyst degradation during their application in different chemical processes. Presented SEM pictures have been taken on a SEM JOEL ISM 35 over 25 years of studies in the field of heterogeneous catalysis.

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Giebler, Michael, Clemens Sperling, Simon Kaiser, Ivica Duretek, and Sandra Schlögl. "Epoxy-Anhydride Vitrimers from Aminoglycidyl Resins with High Glass Transition Temperature and Efficient Stress Relaxation." Polymers 12, no. 5 (May 17, 2020): 1148. http://dx.doi.org/10.3390/polym12051148.

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Epoxy-anhydride vitrimers are covalent adaptable networks, which undergo associative bond exchange reactions at elevated temperature. Their service temperature is influenced by the glass transition temperature (Tg) as well as the topology freezing transition temperature (Tv), at which the covalent bond exchange reactions become significantly fast. The present work highlights the design of high-Tg epoxy-anhydride vitrimers that comprise an efficient stress relaxation at elevated temperature. Networks are prepared by thermally curing aminoglycidyl monomers with glutaric anhydride in different stoichiometric ratios. The tertiary amine groups present in the structure of the aminoglycidyl derivatives not only accelerate the curing reaction but also catalyse the transesterification reaction above Tv, as shown in stress relaxation measurements. The topology rearrangements render the networks recyclable, which is demonstrated by reprocessing a grinded powder of the cured materials in a hot press. The epoxy-anhydride vitrimers are characterised by a high Tg (up to 140 °C) and an adequate storage modulus at 25 °C (~2.5 GPa), which makes them interesting candidates for structural applications operating at high service temperature.

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Malhotra, Charru, Rashmi Anand, and Vivek Soni. "Creating Public Services 4.0: Sustainable Digital Architecture for Public Services in India." Indian Journal of Public Administration 66, no. 3 (September 2020): 327–42. http://dx.doi.org/10.1177/0019556120957421.

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Public Service Delivery (PSD), a basic responsibility of any democratic nation, is understood as the equitable, transparent and efficient deliverance of various public goods and services to its citizens. Prudent application of digital technologies, particularly Emerging Technologies (ETs) and associated software applications, can serve as a valuable tool to catalyse governance towards Sustainable Development Goals (SDGs). While adhering to the principles of good governance. In view of this, the present study is an attempt to first elucidate some global best practices of ETs such as Artificial Intelligence, blockchain, robotic process automation, Virtual Reality and Augmented Reality to articulate the objectives of similar technology application in inspirational terms for PSD in India. Second, it summarises the challenges about the utilisation and exploitation of such technology implementations in the context of developing countries such as India. Based on learnings emanating from these two objectives, the study establishes that a refurbished approach towards digital governance is the need of the hour. This new approach must be citizen-centric, innovative and citizen-inclusive, as the literature affirms that civic participation is a prerequisite while deploying digital technologies. This inspires the authors to propose a model that is co-created with citizens to address the contextual needs and aspirations of citizenry. The successful implementation of the proposed model insists on the presence of a flexible and responsive legal and regulatory system too. The present study may be useful for public administrators and policy makers in understanding the Indian character of using and creating a sustainable digital architecture for PSD that would go a long way in revamping Public Services 4.0 under the ambit of newer Government 4.0 to achieve SDGs by 2030.

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Khangarot, Rama Kanwar, Manisha Khandelwal, and Sumit Kumar Ray. "Syntheses and Applications of Singh’s Catalyst." Synthesis 52, no. 23 (August 19, 2020): 3577–82. http://dx.doi.org/10.1055/s-0040-1707235.

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Singh’s catalyst has emerged as one of the most promising and valuable catalysts in the field of asymmetric synthesis. Since its discovery, it has proven to be one of the best organocatalysts for asymmetric direct aldol reactions, and is equally efficient in aqueous and organic media. In this Short Review, we summarize reactions utilizing Singh’s catalyst under various conditions.1 Introduction2 Synthesis of Singh’s Catalyst3 Applications in Asymmetric Synthesis4 Conclusion

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Mollaoglu, Sinem, Citra Chergia, Esin Ergen, and Matt Syal. "Diffusion of green building guidelines as innovation in developing countries." Construction Innovation 16, no. 1 (January 4, 2016): 11–29. http://dx.doi.org/10.1108/ci-09-2014-0045.

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Purpose – The purpose of this paper is to comprehend the ways of knowledge and application of green building guidelines and assessment systems as innovations diffuse in developing countries’ Architecture Engineering and Construction (AEC) industries. Design/methodology/approach – Building up on recent research on the India case, this study focused on Indonesia and Turkey and further studied “how green building assessment systems diffuse in developing countries”. A total of 110 experts representing individuals from private and governmental sectors from both countries responded to the conducted survey. Findings – Findings show insights to adoption of green building guidelines in developing countries, including their diffusion paths, barriers to their use and their applications. Additionally, the results are compared with the India case from the recent literature and analysed via the lens of the diffusion of innovation theory. Research limitations/implications – A random sampling of the AEC industries in developing countries in future studies and capturing of the evolution of the trends over time will provide further insights into the diffusion of innovation phenomena in the context of green building guidelines. Practical implications – Innovation adoption paths for green building guidelines in Indonesia, Turkey and India are similar, while a higher adoption rate is observed in the case of India. “Diffusion of innovation” categories for green building guidelines that define the state of each adopter at the time of survey conduct in India, Indonesia and Turkey are found. Environmental groups as innovator, large business houses as early adopter and nodal agencies as early majority are the common adopters and categories of green building guidelines. The study findings align with those in the literature and show that clients and market conditions can catalyse the diffusion of innovation in AEC industries in Turkey and Indonesia. Social implications – Diffusion of green building guidelines as innovations in developing countries’ AEC industries showed alignment with the Roger’s (2003) model. However, respondents in both Turkey and Indonesia reported approximately ten times as many innovators and twice as many early adopters as Roger’s (2003) model would predict. Because of the small proportions of late adopters and laggards in these two countries, any useful innovation should be quickly incorporated. Originality/value – Aligning with the literature, findings show that clients and market conditions catalyse diffusion of innovation in AEC industries in Turkey and Indonesia. It is important to note that both countries approximately have ten times as many innovators and twice as many early adopters as theory would predict. Because of the small proportions of late adopters and laggards in these two countries, useful green building innovations could be quickly incorporated.

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Zhang, Yu Li, Xiang Ying Hao, Cui Zhang, and De Yun Ma. "Application of SO₄^2-/ Al-Fe-Activated Solid Acid Catalyst Prepared by Cross-Linking Method." Applied Mechanics and Materials 448-453 (October 2013): 2929–32. http://dx.doi.org/10.4028/www.scientific.net/amm.448-453.2929.

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SO42-/ Al-Fe-activated solid acid catalyst has been prepared using cross-linking method, and characterized by FTIR spectra, TG-DTA, XRD analysis. The catalyst is able to effectively catalyse the hydration of turpentine to α-terpineol, with the conversion up to 40% after > 4 uses.

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Petrauskas, Karolis, and Romas Baronas. "Biojutiklių, modeliuojamų dvimatėje erdvėje, kompiuterinių modelių automatizuotas sudarymas." Informacijos mokslai 42, no. 43 (January 1, 2008): 108–13. http://dx.doi.org/10.15388/im.2008.0.3434.

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Biojutikliai yra plačiai naudojami tirti medžiagų koncentracijai tirpaluose. Viena pagrindinių biojutiklio sudedamųjų dalių yra fermentas. Fermentai yra gana brangios medžiagos, dėl to ir vykdyti eksperimentus yra brangu. Kuriant naujus biojutiklius tenka atlikti daug eksperimentų. Kad būtų sumažintas reikiamų eksperimentų skaičius, taikomas kompiuterinis biojutiklių veiksmo modeliavimas. Dažniausiai konkrečios geometrijos biojutikliui kuriamas konkretus jo kompiuterinis modelis. Šiame straipsnyje pristatoma sistema, kuri gali prisitaikyti prie konkrečios geometrijos biojutiklio. Sistema gali būti taikoma biojutikliams, kurių veiksmas aprašomas matematiniais modeliais, formuluojamais dvimatėje stačiakampėje srityje. Konkretaus biojutiklio matematinio modelio sprendinys komponuojamas parenkant konkrečius algoritmus.Computer aided model composition for biosensors modelled in two-dimensional spaceKarolis Petrauskas, Romas Baronas SummaryBiosensors are analytical devices that use biological components, usually enzymes, which catalyse the interaction with a target analyte. Biosensors are widely used in clinical, environment and industrial applications for the determination of species concentrations. In some applications of biosensors, enzymes are very expensive and only available in very limited quantity. In design of novel highly sensitive biosensors a lot of experiments are required. Computer simulation of the biosensor action is an effective way to decrease a number of physical experiments. This paper presents a system adaptive to a concrete geometry of the biosensor. The system may be applied for biosensors, the action of which can be described by a mathematical model formulated in a two dimensional space. A simulator for a concrete biosensor is generated from the detailed description of the biosensor action.eight: 18px;">

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Journal articles on the topic 'Applications en catalyse'

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