function Ergothioneine improves cognitive function by ameliorating mitochondrial damage and decreasing neuroinflammation in a D-galactose-induced aging model By pubs.rsc.org Published On :: Food Funct., 2024, Advance ArticleDOI: 10.1039/D4FO02321H, PaperFangyang Chen, Botao Wang, Xin Sun, Yage Wang, Ruiyan Wang, Kaikai LiEGT intervention significantly improved D-galactose induced oxidative stress, neuroinflammation, and mitochondrial function, resulting in the alleviation of memory injury.To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function MOF-derived N-doped CoNi@C as bifunctional catalysts for efficient water splitting By pubs.rsc.org Published On :: Catal. Sci. Technol., 2024, Advance ArticleDOI: 10.1039/D4CY00924J, PaperXihui Yang, Zekun Li, Zikun Yang, Dapeng Meng, Zhao WangCoNi@C core–shell catalysts from ZIF-67 were synthesized for efficient water splitting. The hydrophilic carbon shell inhibits metal oxidation. The CoNi alloy serves as the active site, while nitrogen doping promotes the electrocatalytic performance.To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Vibrational frequencies utilized for the assessment of exchange–correlation functionals in the description of metal–adsorbate systems: C2H2 and C2H4 on transition-metal surfaces By pubs.rsc.org Published On :: Catal. Sci. Technol., 2024, Advance ArticleDOI: 10.1039/D4CY00685B, PaperRay Miyazaki, Somayeh Faraji, Sergey V. Levchenko, Lucas Foppa, Matthias SchefflerVibrational frequencies can be utilized as a reference to assess the reliability of the exchange–correlation functionals.To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Sulfonic acid-modified MOFs as heterogeneous bifunctional catalysts for ethylene oligomerization at room temperature without cocatalysts By pubs.rsc.org Published On :: Catal. Sci. Technol., 2024, 14,6270-6277DOI: 10.1039/D4CY00502C, PaperYao Ning, Yuqi Yang, Dongming Shan, Shuxing Mei, Yibai Yan, Linjie Ding, Ying ZhangEthylene oligomerization plays an important role in industrial production.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function All-in-one Rh(III)-covalent organic framework for sustainable and regioselective C(sp2)–H bond functionalization By pubs.rsc.org Published On :: Catal. Sci. Technol., 2024, Advance ArticleDOI: 10.1039/D4CY01098A, PaperLuohe Wang, Junnan E, Xiubin Bu, Jing Zeng, Xiaobo Yang, Hua Fu, Zhen ZhaoRhCOF-SYNU-1 serves as a transition-metal catalyst, photocatalyst, and metal ligand, enabling regioselective C(sp2)–H bond functionalization and offering a sustainable approach for Rh(III) catalysis.To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Recyclable copper(I)-catalyzed cascade C–S and C–N bond formation between 2-iodoanilines and 2-bromobenzenethiols towards functionalized phenothiazines By pubs.rsc.org Published On :: Catal. Sci. Technol., 2024, 14,6561-6572DOI: 10.1039/D4CY00888J, PaperYan Wang, Chengkai Luo, Li Wei, Mingzhong CaiHeterogeneous copper-catalyzed heterocyclization between 2-iodoanilines and 2-bromothiophenols has been developed for the assembly of substituted phenothiazines.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Bifunctional catalysts based on PdZn/ZnO and hierarchical zeolites in the direct synthesis of dimethyl ether from CO-rich syngas: influence of the support and the Zn/Pd molar ratio By pubs.rsc.org Published On :: Catal. Sci. Technol., 2024, Advance ArticleDOI: 10.1039/D4CY00860J, Paper Open Access   This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.Bing Wang, Nicola Da Roit, Michael Zimmermann, Markus Boese, Thomas Zevaco, Silke BehrensPd/Zn-nanoparticles were used as precursors to study the influence of the molar Zn/Pd ratio and hierarchical HZSM-5 zeolites in the syngas-to-dimethyl ether process.To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Effect of graphene electrode functionalization on machine learning-aided single nucleotide classification By pubs.rsc.org Published On :: Nanoscale, 2024, 16,20202-20215DOI: 10.1039/D4NR02274B, PaperMohd Rashid, Milan Kumar Jena, Sneha Mittal, Biswarup PathakIn this study, we explored the role of functionalized entities (C, H, N, and OH) in graphene electrodes using a machine learning (ML) framework integrated with the quantum transport method to achieve precise single DNA nucleotide identification.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Effective enrichment of glycated proteome using ultrasmall gold nanoclusters functionalized with boronic acid By pubs.rsc.org Published On :: Nanoscale, 2024, 16,20147-20154DOI: 10.1039/D4NR03283G, PaperHongmae Heo, Seonghyeon Cho, Yuhyeon Kim, Soomin Ahn, Jeong-hun Mok, Hookeun Lee, Dongil LeeA novel approach was developed for the first time by combining ultrasmall Au22 nanoclusters with boronic acid (BA) affinity chemistry, achieving highly efficient enrichment of early-stage glycated peptides.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Polylactic acid/chitosan-IKVAV Janus film serving as a dual functional platform for spinal cord injury repair By pubs.rsc.org Published On :: Nanoscale, 2024, Advance ArticleDOI: 10.1039/D4NR02248C, PaperLiyang Yu, Haoyong Jin, He Xia, Xiaoxiong Wang, Liang Wang, Dezheng Li, Jiangli Zhao, Yuanhua Sang, Jichuan Qiu, Ning Lu, Hong Liu, Ning YangSchematic showing the PLA/CS-IKVAV Janus film for promoting neuronal differentiation and SCI repair.To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Biomass-derived substrates hydrogenation over Rhodium Nanoparticles Supported on Functionalized Mesoporous Silica By pubs.rsc.org Published On :: Nanoscale, 2024, Accepted ManuscriptDOI: 10.1039/D4NR02579B, Paper Open Access   This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.Israel Tonatiuh Pulido-Díaz, Draco Martínez, Karla Patricia Salas-Martin, Benjamín Portales-Martínez, Dominique Agustin, Antonio Reina, Itzel Guerrero RíosThe use of supported rhodium nanoparticles (RhNPs) is gaining attention due to the drive for better catalyst performance and sustainability. Silica-based supports are promising for RhNP immobilization because of their...The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Photo-Assisted Epitaxial Growth from Nanoparticles to Enhance Multi-Materialization for Advanced Surface Functionalization By pubs.rsc.org Published On :: Nanoscale, 2024, Accepted ManuscriptDOI: 10.1039/D4NR03112A, PaperMasayuki Fukuda, Yuuki Kitanaka, Tomohiko NakajimaTo meet the requirements of freeform objects, a wide range of highly designable resin-based materials has been created, highlighting the need for low-temperature ceramic deposition methods for surface functionalization. Photo-assisted...The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Bifunctional electrocatalytic hybrid heterostructures for polysulfide anchoring/conversion for a stable lithium–sulfur battery By pubs.rsc.org Published On :: Nanoscale, 2024, Advance ArticleDOI: 10.1039/D4NR03190C, PaperSakthivel Kaliyaperumal, Karthik Kiran Sarigamala, Padmini Moorthy, Balaji Ramachandran, Narendhar Chandrasekar, Tim AlbrechtIn situ phase engineering of transition metal dichalcogenides (TMDs) based hybrid heterostructures with controlled sulfur vacancies offers a promising strategy for superior-performance lithium–sulfur (Li–S) batteries.To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Aptamer-functionalized Nucleic Acid Nanotechnology for Biosensing, Bioimaging and Cancer Therapy By pubs.rsc.org Published On :: Nanoscale, 2024, Accepted ManuscriptDOI: 10.1039/D4NR04360J, Review ArticleXiaofang Zheng, Zhiyong Huang, Qiang Zhang, Guoli Li, Minghui Song, Ruizi PengNucleic acids have enabled to fabricate self-assemblies and perform dynamic operations. Among different functional nucleic acids, aptamers can specifically bind to wide range of targets including proteins, viral antigens, living...The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Expression of concern: Iron oxide magnetic nanoparticles with versatile surface functions based on dopamine anchors By pubs.rsc.org Published On :: Nanoscale, 2024, Advance ArticleDOI: 10.1039/D4NR90209B, Expression of Concern Open Access   This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.Mykola Mazur, Alexandre Barras, Victor Kuncser, Andrei Galatanu, Vladimir Zaitzev, Kostiantyn V. Turcheniuk, Patrice Woisel, Joel Lyskawa, William Laure, Aloysius Siriwardena, Rabah Boukherroub, Sabine SzuneritsTo cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Bi-functional quercetin/copper nanoparticles integrating bactericidal and anti-quorum sensing properties for preventing the formation of biofilms By pubs.rsc.org Published On :: Biomater. Sci., 2024, 12,1788-1800DOI: 10.1039/D4BM00034J, PaperJingjing Cheng, Haixin Zhang, Kunyan Lu, Yi Zou, Dongxu Jia, Hong Yang, Hong Chen, Yanxia Zhang, Qian YuA bi-functional antibiofilm nanoplatform was developed based on a complex of quercetin and copper integrating bactericidal and anti-quorum sensing properties.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function N-Halaminated spermidine-containing polymeric coating enables titanium to achieve dual functions of antibacterial and osseointegration By pubs.rsc.org Published On :: Biomater. Sci., 2024, Advance ArticleDOI: 10.1039/D4BM00061G, PaperHang Ren, Peng Wang, Hanwen Huang, Junshen Huang, Yuheng Lu, Yanfeng Wu, Zhongyu Xie, Youchen Tang, Zhaopeng Cai, Huiyong ShenModified Ti with a porous N-halaminated spermidine-containing polymeric coating is constructed, and it has both excellent antibacterial and osteogenic abilities to enhance osseointegration, making it potentially applicable in orthopedics.To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Multifunctional antibacterial hydrogels for chronic wound management By pubs.rsc.org Published On :: Biomater. Sci., 2024, Advance ArticleDOI: 10.1039/D4BM00155A, Review Article Open Access   This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.Yungang Hu, Lu Yu, Qiang Dai, Xiaohua Hu, Yuming ShenDue to their distinctive physical and chemical properties as well as their biological functionalities, multifunctional antibacterial hydrogels possess significant advantages in the treatment of chronic wounds.To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Bioactivity of cerium dioxide nanoparticles as a function of size and surface features By pubs.rsc.org Published On :: Biomater. Sci., 2024, Advance ArticleDOI: 10.1039/D3BM01900D, PaperVeronika Sarnatskaya, Yuliia Shlapa, Denis Kolesnik, Olexandra Lykhova, Dmytro Klymchuk, Serhii Solopan, Svitlana Lyubchyk, Iuliia Golovynska, Junle Qu, Yurii Stepanov, Anatolii BelousNano-dispersed cerium dioxide is promising for use in medicine due to its unique physicochemical properties, low toxicity, the safety of in vivo usage, active participation in different redox processes occurring in living cells, and its regenerative potential.To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Samsung launches newest Galaxy S24 smartphones with AI functions By www.thehindubusinessline.com Published On :: Thu, 18 Jan 2024 00:47:01 +0530 Samsung looks to take on Apple with their latest AI functions in the S24 range. Full Article Info-tech
function Multifunctional nanofibers filter dust and fight fire By cen.acs.org Published On :: 07 Jul 2018 13:07:03 +0000 Nylon 6 nanofibers contain flame-retardant core Full Article
function Multi-task Rhodium-Catalyzed Remote C(sp3)–H Functionalization Reactions of Acyclic Dienes to Yield Benzene-fused Heterocycles By pubs.rsc.org Published On :: Green Chem., 2024, Accepted ManuscriptDOI: 10.1039/D4GC04927F, PaperYuta Sato, Momoko Nagafuchi, Masaharu Takatsuki, Tsuyoshi Matsuzaki, Takeyuki Suzuki, Makoto Sako, Mitsuhiro ArisawaRemote C(sp3)–H bond functionalization reactions are environmentally benign methods for not only acyclic molecules but also cyclic molecules. However, previous reports' products have been limited to aliphatic five-membered ring structures....The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function Ball milling-promoting difunctionalization of alkynyl sulfonium salts with sulfinic acids towards (Z)-1,2-disulfonylethenes By pubs.rsc.org Published On :: Green Chem., 2024, Advance ArticleDOI: 10.1039/D4GC04895D, PaperLi-Hua Yang, Bei Li, Lin Chen, Wen-Shi Yao, Han-Yue Peng, Sha Peng, Long-Yong XieA simple ball milling-mediated disulfonylation of alkynyl sulfonium salts with sulfinic acids for the stereoselective synthesis of various (Z)-1,2-disulfonylethenes has been developed under catalyst-, additive- and solvent-free conditions.To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function 1D/3D hierarchical carbon skeleton confined NiFe nanoparticles with optimized three-phase interfaces as tri-functional electrocatalysts By pubs.rsc.org Published On :: Green Chem., 2024, Advance ArticleDOI: 10.1039/D4GC04466E, PaperYuqing Chen, Binyang Liu, Xuesong Liu, Jiahui Ye, Kuan Deng, Chengjie Wu, Qiang Niu, Tao Yang, Wen Tian, Junyi JiMultilevel 1D/3D CNTs/carbon spheres with hydrophilicity can promote the infiltration of an electrolyte into the interior and guide bubble diffusion, thus constructing an optimal gas–solid–liquid interface to enhance the electrocatalytic process.To cite this article before page numbers are assigned, use the DOI form of citation above.The content of this RSS Feed (c) The Royal Society of Chemistry Full Article
function SPPU hostel water filters non-functional, ABVP conducts mock funeral in protest By indianexpress.com Published On :: Sun, 10 Nov 2024 05:40:57 +0000 Full Article Cities Pune
function Malayali weddings embrace traditions from across India by including functions such as ‘mehendi’, ‘haldi’ and Bollywood frills as part of the celebrations By www.thehindu.com Published On :: Fri, 21 Oct 2022 12:40:01 +0530 Haldi, mehendi and sangeet have been enthusiastically borrowed by young couples to add colour, music and fun to the relatively simple Malayali wedding Full Article Life & Style
function Kylie Jenner Shares Her Wardrobe Malfunction Experience In Black Gown From Met Gala 2018 By www.boldsky.com Published On :: Wed, 06 May 2020 18:15:31 +0530 With grand events like Met Gala comes big responsibility not just for the hosts but also for the celebrities. After all, they are the ones who grace the red carpet with their dazzling fashionable outfits. The fear of wardrobe malfunction Full Article
function Schoenberg's atonal music: musical idea, basic image, and specters of tonal function / Jack Boss By library.mit.edu Published On :: Sun, 10 May 2020 07:43:52 EDT Lewis Library - ML410.S283 B66 2019 Full Article
function ecommerce with specific functionality or requirements By forums.digitalpoint.com Published On :: Sun, 10 May 2020 00:49:58 +0000 Full Article
function Development of a novel {beta}-1,6-glucan-specific detection system using functionally-modified recombinant endo-{beta}-1,6-glucanase [Methods and Resources] By feedproxy.google.com Published On :: 2020-04-17T00:06:05-07:00 β-1,3-d-Glucan is a ubiquitous glucose polymer produced by plants, bacteria, and most fungi. It has been used as a diagnostic tool in patients with invasive mycoses via a highly-sensitive reagent consisting of the blood coagulation system of horseshoe crab. However, no method is currently available for measuring β-1,6-glucan, another primary β-glucan structure of fungal polysaccharides. Herein, we describe the development of an economical and highly-sensitive and specific assay for β-1,6-glucan using a modified recombinant endo-β-1,6-glucanase having diminished glucan hydrolase activity. The purified β-1,6-glucanase derivative bound to the β-1,6-glucan pustulan with a KD of 16.4 nm. We validated the specificity of this β-1,6-glucan probe by demonstrating its ability to detect cell wall β-1,6-glucan from both yeast and hyphal forms of the opportunistic fungal pathogen Candida albicans, without any detectable binding to glucan lacking the long β-1,6-glucan branch. We developed a sandwich ELISA-like assay with a low limit of quantification for pustulan (1.5 pg/ml), and we successfully employed this assay in the quantification of extracellular β-1,6-glucan released by >250 patient-derived strains of different Candida species (including Candida auris) in culture supernatant in vitro. We also used this assay to measure β-1,6-glucan in vivo in the serum and in several organs in a mouse model of systemic candidiasis. Our work describes a reliable method for β-1,6-glucan detection, which may prove useful for the diagnosis of invasive fungal infections. Full Article
function Obesity alters brain structure and function By www.theguardian.com Published On :: 2016-11-23T18:30:50Z It’s not just your waistline that suffers as you put on weight. Researchers are beginning to find puzzling new links between obesity, memory loss and dementiaLucy Cheke and her colleagues at the University of Cambridge recently invited a few participants into her lab for a kind of ‘treasure hunt’.The participants navigated a virtual environment on a computer screen, dropping off various objects along their way. They then answered a series of questions to test their memory of the task, such as where they had hidden a particular object. Related: How your eyes betray your thoughts Related: How to optimise your brain's waste disposal system Related: Gut bacteria regulate nerve fibre insulation Related: Obesity linked to memory deficits Continue reading... Full Article Science Neuroscience
function Breathing modulates brain activity and mental function By www.theguardian.com Published On :: 2016-12-23T10:30:13Z New research shows that the rhythm of breathing directly impacts neural activity in a network of brain areas involved in smell, memory and emotionsThe rhythm of breathing co-ordinates electrical activity across a network of brain regions associated with smell, memory, and emotions, and can enhance their functioning, according to a new study by researchers at Northwestern University. The findings, published in the Journal of Neuroscience, suggest that breathing does not merely supply oxygen to the brain and body, but may also organise the activity of populations of cells within multiple brain regions to help orchestrate complex behaviours. Related: Your nose knows death is imminent | Mo Costandi Related: A cooler way to evaluate brain surgery patients Continue reading... Full Article Science Neuroscience
function Schools are functioning despite extraordinary challenges, no ground to deny them fees By www.financialexpress.com Published On :: 2020-04-30T03:55:00+05:30 However, the High Court rejected this invocation of Rule 165, ruling that the it specified only the payability conditions of fees, and not the chargeability of it. Full Article Opinion
function GSTN develops functionality for transfer of amount available in electronic cash ledger By www.financialexpress.com Published On :: 2020-05-05T18:30:00+05:30 In a statement, GSTN said this new functionality on the GST portal is aimed at providing a major relief to taxpayers, especially at the time of the COVID-19 crisis when there is limited access to cash resources. Full Article Economy
function Aha by HARMAN Cloud Platform 'Future Proofs' Vehicles with Services that Update Infotainment Systems and Provide Real Time Analytics and Extend System Functionality By news.harman.com Published On :: Mon, 06 Jan 2014 13:00:00 GMT CES 2014, LAS VEGAS – HARMAN, the premium global audio and infotainment group (NYSE:HAR), unveiled two new services for the automotive market that leverage the Aha by HARMAN Cloud Platform and HARMAN’s infotainment system design leadership to ensure safe, personalized and connected driving experiences throughout the life of the vehicle. Extending beyond the popular Aha Radio interactive content service, the new Aha Updates and Aha Analytics services take HARMAN’s expertise and investments in cloud infrastructure into new directions. Full Article
function $100k, draft picks: AFL greats debate Adelaide’s ‘training malfunction’ penalties By www.foxsports.com.au Published On :: 2020-05-09T02:29:00.000+00:00 AFL greats Dermott Brereton and David King have debated the merits of a severe penalty for the Adelaide Crows, following a “training malfunction” on Thursday. Full Article
function Cheap Lululemon Athletic Shoe - Fashion or Functional? by Julie Pitts By feedproxy.google.com Published On :: Publicity galloped, feel sharp cold air from ear roared and had, Blaster beyond, listening noisy glitz from inside waved bulk far to, in a a people of dynamic world in the, understanding new of life,... Full Article
function MSMEs likely to start functioning from Monday By www.thehindu.com Published On :: Sat, 09 May 2020 22:58:54 +0530 Several micro, small and medium-scale enterprises (MSMEs) in Coimbatore Corporation limits are expected to start operations on Monday. “The order issu Full Article Coimbatore
function BJP functionaries fight over ration distribution By Published On :: BJP functionaries fight over ration distribution Full Article
function 45 retail fruit shops to function from school By www.thehindu.com Published On :: Sat, 09 May 2020 21:56:30 +0530 This will reduce crowding at the market at Mattuthavani Full Article Madurai
function Structure and function of dioxygenases in histone demethylation and DNA/RNA demethylation By journals.iucr.org Published On :: The structure and function of dioxygenases in histone demethylation and DNA/RNA dimethylation are discussed. Full Article text
function Structure–function study of AKR4C14, an aldo-keto reductase from Thai Jasmine rice (Oryza sativa L. ssp. Indica cv. KDML105) By journals.iucr.org Published On :: Rice AKR in the apo structure reveals the ordered open conformation and its key residues which form the substrate channel wall and determine its substrate preference for straight-chain aldehydes. Full Article text
function Functionalized 3-(5-aryloxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)-1-(4-substituted-phenyl)prop-2-en-1-ones: synthetic pathway, and the structures of six examples By scripts.iucr.org Published On :: 2020-04-21 Five examples each of 3-(5-aryloxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)-1-[4-(prop-2-yn-1-yloxy)phenyl]prop-2-en-1-ones and the corresponding 1-(4-azidophenyl)-3-(5-aryloxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)prop-2-en-1-ones have been synthesized in a highly efficient manner, starting from a common source precursor, and structures have been determined for three examples of each type. In each of 3-[5-(2-chlorophenoxy)-3-methyl-1-phenyl-1H-pyrazol-4-yl]-1-[4-(prop-2-yn-1-yloxy)phenyl]prop-2-en-1-one, C28H21ClN2O3, (Ib), the isomeric 3-[5-(2-chlorophenoxy)-3-methyl-1-phenyl-1H-pyrazol-4-yl]-1-[4-(prop-2-yn-1-yloxy)phenyl]prop-2-en-1-one, (Ic), and 3-[3-methyl-5-(naphthalen-2-yloxy)-1-phenyl-1H-pyrazol-4-yl]-1-[4-(prop-2-ynyloxy)phenyl]prop-2-en-1-one, C32H24N2O3, (Ie), the molecules are linked into chains of rings, formed by two independent C—H⋯O hydrogen bonds in (Ib) and by a combination of C—H⋯O and C—H⋯π(arene) hydrogen bonds in each of (Ic) and (Ie). There are no direction-specific intermolecular interactions in the structure of 1-(4-azidophenyl)-3-[3-methyl-5-(2-methylphenoxy)-1-phenyl-1H-pyrazol-4-yl]prop-2-en-1-one, C26H21N5O2, (IIa). In 1-(4-azidophenyl)-3-[5-(2,4-dichlorophenoxy)-3-methyl-1-phenyl-1H-pyrazol-4-yl]prop-2-en-1-one, C25H17Cl2N5O2, (IId), the dichlorophenyl group is disordered over two sets of atomic sites having occupancies 0.55 (4) and 0.45 (4), and the molecules are linked by a single C—H⋯O hydrogen bond to form cyclic, centrosymmetric R22(20) dimers. Similar dimers are formed in 1-(4-azidophenyl)-3-[3-methyl-5-(naphthalen-2-yloxy)-1-phenyl-1H-pyrazol-4-yl]prop-2-en-1-one, C29H21N5O2, (IIe), but here the dimers are linked into a chain of rings by two independent C—H..π(arene) hydrogen bonds. Comparisons are made between the molecular conformations within both series of compounds. Full Article text
function Energetics of interactions in the solid state of 2-hydroxy-8-X-quinoline derivatives (X = Cl, Br, I, S-Ph): comparison of Hirshfeld atom, X-ray wavefunction and multipole refinements By scripts.iucr.org Published On :: 2019-07-15 In this work, two methods of high-resolution X-ray data refinement: multipole refinement (MM) and Hirshfeld atom refinement (HAR) – together with X-ray wavefunction refinement (XWR) – are applied to investigate the refinement of positions and anisotropic thermal motion of hydrogen atoms, experiment-based reconstruction of electron density, refinement of anharmonic thermal vibrations, as well as the effects of excluding the weakest reflections in the refinement. The study is based on X-ray data sets of varying quality collected for the crystals of four quinoline derivatives with Cl, Br, I atoms and the -S-Ph group as substituents. Energetic investigations are performed, comprising the calculation of the energy of intermolecular interactions, cohesive and geometrical relaxation energy. The results obtained for experimentally derived structures are verified against the values calculated for structures optimized using dispersion-corrected periodic density functional theory. For the high-quality data sets (the Cl and -S-Ph compounds), both MM and XWR could be successfully used to refine the atomic displacement parameters and the positions of hydrogen atoms; however, the bond lengths obtained with XWR were more precise and closer to the theoretical values. In the application to the more challenging data sets (the Br and I compounds), only XWR enabled free refinement of hydrogen atom geometrical parameters, nevertheless, the results clearly showed poor data quality. For both refinement methods, the energy values (intermolecular interactions, cohesive and relaxation) calculated for the experimental structures were in similar agreement with the values associated with the optimized structures – the most significant divergences were observed when experimental geometries were biased by poor data quality. XWR was found to be more robust in avoiding incorrect distortions of the reconstructed electron density as a result of data quality issues. Based on the problem of anharmonic thermal motion refinement, this study reveals that for the most correct interpretation of the obtained results, it is necessary to use the complete data set, including the weak reflections in order to draw conclusions. Full Article text
function Structures of three ependymin-related proteins suggest their function as a hydrophobic molecule binder By scripts.iucr.org Published On :: 2019-06-20 Ependymin was first discovered as a predominant protein in brain extracellular fluid in fish and was suggested to be involved in functions mostly related to learning and memory. Orthologous proteins to ependymin called ependymin-related proteins (EPDRs) have been found to exist in various tissues from sea urchins to humans, yet their functional role remains to be revealed. In this study, the structures of EPDR1 from frog, mouse and human were determined and analyzed. All of the EPDR1s fold into a dimer using a monomeric subunit that is mostly made up of two stacking antiparallel β-sheets with a curvature on one side, resulting in the formation of a deep hydrophobic pocket. All six of the cysteine residues in the monomeric subunit participate in the formation of three intramolecular disulfide bonds. Other interesting features of EPDR1 include two asparagine residues with glycosylation and a Ca2+-binding site. The EPDR1 fold is very similar to the folds of bacterial VioE and LolA/LolB, which also use a similar hydrophobic pocket for their respective functions as a hydrophobic substrate-binding enzyme and a lipoprotein carrier, respectively. A further fatty-acid binding assay using EPDR1 suggests that it indeed binds to fatty acids, presumably via this pocket. Additional interactome analysis of EPDR1 showed that EPDR1 interacts with insulin-like growth factor 2 receptor and flotillin proteins, which are known to be involved in protein and vesicle translocation. Full Article text
function A complete compendium of crystal structures for the human SEPT3 subgroup reveals functional plasticity at a specific septin interface By scripts.iucr.org Published On :: 2020-03-28 Human septins 3, 9 and 12 are the only members of a specific subgroup of septins that display several unusual features, including the absence of a C-terminal coiled coil. This particular subgroup (the SEPT3 septins) are present in rod-like octameric protofilaments but are lacking in similar hexameric assemblies, which only contain representatives of the three remaining subgroups. Both hexamers and octamers can self-assemble into mixed filaments by end-to-end association, implying that the SEPT3 septins may facilitate polymerization but not necessarily function. These filaments frequently associate into higher order complexes which associate with biological membranes, triggering a wide range of cellular events. In the present work, a complete compendium of crystal structures for the GTP-binding domains of all of the SEPT3 subgroup members when bound to either GDP or to a GTP analogue is provided. The structures reveal a unique degree of plasticity at one of the filamentous interfaces (dubbed NC). Specifically, structures of the GDP and GTPγS complexes of SEPT9 reveal a squeezing mechanism at the NC interface which would expel a polybasic region from its binding site and render it free to interact with negatively charged membranes. On the other hand, a polyacidic region associated with helix α5', the orientation of which is particular to this subgroup, provides a safe haven for the polybasic region when retracted within the interface. Together, these results suggest a mechanism which couples GTP binding and hydrolysis to membrane association and implies a unique role for the SEPT3 subgroup in this process. These observations can be accounted for by constellations of specific amino-acid residues that are found only in this subgroup and by the absence of the C-terminal coiled coil. Such conclusions can only be reached owing to the completeness of the structural studies presented here. Full Article text
function Structural and functional characterization of CMP-N-acetylneuraminate synthetase from Vibrio cholerae By scripts.iucr.org Published On :: 2019-05-31 Several pathogenic bacteria utilize sialic acid, including host-derived N-acetylneuraminic acid (Neu5Ac), in at least two ways: they use it as a nutrient source and as a host-evasion strategy by coating themselves with Neu5Ac. Given the significant role of sialic acid in pathogenesis and host-gut colonization by various pathogenic bacteria, including Neisseria meningitidis, Haemophilus influenzae, Pasteurella multocida and Vibrio cholerae, several enzymes of the sialic acid catabolic, biosynthetic and incorporation pathways are considered to be potential drug targets. In this work, findings on the structural and functional characterization of CMP-N-acetylneuraminate synthetase (CMAS), a key enzyme in the incorporation pathway, from Vibrio cholerae are reported. CMAS catalyzes the synthesis of CMP-sialic acid by utilizing CTP and sialic acid. Crystal structures of the apo and the CDP-bound forms of the enzyme were determined, which allowed the identification of the metal cofactor Mg2+ in the active site interacting with CDP and the invariant Asp215 residue. While open and closed structural forms of the enzyme from eukaryotic and other bacterial species have already been characterized, a partially closed structure of V. cholerae CMAS (VcCMAS) observed upon CDP binding, representing an intermediate state, is reported here. The kinetic data suggest that VcCMAS is capable of activating the two most common sialic acid derivatives, Neu5Ac and Neu5Gc. Amino-acid sequence and structural comparison of the active site of VcCMAS with those of eukaryotic and other bacterial counterparts reveal a diverse hydrophobic pocket that interacts with the C5 substituents of sialic acid. Analyses of the thermodynamic signatures obtained from the binding of the nucleotide (CTP) and the product (CMP-sialic acid) to VcCMAS provide fundamental information on the energetics of the binding process. Full Article text
function The nondestructive measurement of strain distributions in air plasma sprayed thermal barrier coatings as a function of depth from entire Debye–Scherrer rings By scripts.iucr.org Published On :: 2020-02-01 The residual strain distribution has been measured as a function of depth in both top coat and bond coat in as-received and heat-treated air plasma sprayed thermal barrier coating samples. High-energy synchrotron X-ray beams were used in transmission to produce full Debye–Scherrer rings whose non-circular aspect ratio gave the in-plane and out-of-plane strains far more efficiently than the sin2ψ method. The residual strain in the bond coat is found to be tensile and the strain in the β phase of the as-received sample was measured. The residual strains observed in the top coat were generally compressive (increasing towards the interface), with two kinds of nonlinear trend. These was a `jump' feature near the interface, and in some cases there was another `jump' feature near the surface. It is shown how these trend differences can be correlated to cracks in the coating. Full Article text
function Structure analysis of supported disordered molybdenum oxides using pair distribution function analysis and automated cluster modelling By scripts.iucr.org Published On :: 2020-02-01 Molybdenum oxides and sulfides on various low-cost high-surface-area supports are excellent catalysts for several industrially relevant reactions. The surface layer structure of these materials is, however, difficult to characterize due to small and disordered MoOx domains. Here, it is shown how X-ray total scattering can be applied to gain insights into the structure through differential pair distribution function (d-PDF) analysis, where the scattering signal from the support material is subtracted to obtain structural information on the supported structure. MoOx catalysts supported on alumina nanoparticles and on zeolites are investigated, and it is shown that the structure of the hydrated molybdenum oxide layer is closely related to that of disordered and polydisperse polyoxometalates. By analysing the PDFs with a large number of automatically generated cluster structures, which are constructed in an iterative manner from known polyoxometalate clusters, information is derived on the structural motifs in supported MoOx. Full Article text
function Optimized reconstruction of the crystallographic orientation density function based on a reduced set of orientations By scripts.iucr.org Published On :: 2020-02-01 Crystallographic textures, as they develop for example during cold forming, can have a significant influence on the mechanical properties of metals, such as plastic anisotropy. Textures are typically characterized by a non-uniform distribution of crystallographic orientations that can be measured by diffraction experiments like electron backscatter diffraction (EBSD). Such experimental data usually contain a large number of data points, which must be significantly reduced to be used for numerical modeling. However, the challenge in such data reduction is to preserve the important characteristics of the experimental data, while reducing the volume and preserving the computational efficiency of the numerical model. For example, in micromechanical modeling, representative volume elements (RVEs) of the real microstructure are generated and the mechanical properties of these RVEs are studied by the crystal plasticity finite element method. In this work, a new method is developed for extracting a reduced set of orientations from EBSD data containing a large number of orientations. This approach is based on the established integer approximation method and it minimizes its shortcomings. Furthermore, the L1 norm is applied as an error function; this is commonly used in texture analysis for quantitative assessment of the degree of approximation and can be used to control the convergence behavior. The method is tested on four experimental data sets to demonstrate its capabilities. This new method for the purposeful reduction of a set of orientations into equally weighted orientations is not only suitable for numerical simulation but also shows improvement in results in comparison with other available methods. Full Article text