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991.
Kristelle Hughes Raimana Ho Stphane Greff Gaëtan Herbette Edith Filaire Edwige Ranouille Jean-Yves Berthon Phila Raharivelomanana 《Molecules (Basel, Switzerland)》2022,27(1)
The term cosmetopoeia refers to the use of plants in folks’ cosmetics. The aerial parts of Bidens pilosa L., the leaves of Calophyllum inophyllum L. and the fruits of Fagraea berteroana A.Gray ex Benth are traditionally used in French Polynesia for hair and skin care. During the hair cycle, dermal papilla cells and their interaction with epithelial cells are essential to promote hair follicle elongation. The aim of our investigations was the identification of metabolites from these three plants and chemical families responsible for their hair growth activity. A bioactivity-based molecular network was produced by mapping the correlation between features obtained from LC-MS/MS data and dermal papilla cell proliferation, using the Pearson correlation coefficient. The analyses pointed out glycosylated flavonols and phenolic acids from B. pilosa and C. inophyllum, along with C-flavonoids, iridoids and secoiridoids from F. berteroana, as potential bioactive molecules involved in the proliferation of hair follicle dermal papilla cells. Our results highlight the metabolites of the plant species potentially involved in the induction of hair follicle growth and support the traditional uses of these plants in hair care. 相似文献
992.
V. Meyer S.N. Bagayev P.E.G. Baird P. Bakule M.G. Boshier A. Breitrück S.L. Cornish S. Dychkov G.H. Eaton A. Grossmann D. Hübl V.W. Hughes K. Jungmann I.C. Lane Yi Wei Liu D. Lucas Y. Matyugin J. Merkel G. zu Putlitz I. Reinhard P.G.H. Sandars R. Santra P. Schmidt C.A. Scott W.T. Toner M. Towrie K. Träger L. Willmann V. Yakhontov 《Hyperfine Interactions》2000,127(1-4):197-200
The 1s–2s energy interval in the muonium (μ+e−) atom has been measured by Doppler free two photon laser spectroscopy. A value of 2455528941.0(9.8) MHz has been obtained
in good agreement with quantum electrodynamics (QED). The muon-electron mass ratio can be extracted and is found to be 206.76838(17).
The measurement may also be interpreted as a determination of the muon-electron charge ratio as -1- 1.1(2.1)· 10−9. Corresponding measurements in deuterium using the same experimental setup confirmed the validity of the applied analysis
procedure.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
993.
Tu Sun Dr. Colan E. Hughes Linshuo Guo Lei Wei Prof. Kenneth D. M. Harris Prof. Yue-Biao Zhang Prof. Yanhang Ma 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(50):22827-22833
Structure determination of covalent organic frameworks (COFs) with atomic precision is a bottleneck that hinders the development of COF chemistry. Although three-dimensional electron diffraction (3D-ED) data has been used to solve structures of sub-micrometer-sized COFs, successful structure solution is not guaranteed as the data resolution is usually low. We demonstrate that the direct-space strategy for structure solution, implemented using a genetic algorithm (GA), is a successful approach for structure determination of COF-300 from 3D-ED data. Structural models with different geometric constraints were considered in the GA calculations, with successful structure solution achieved from room-temperature 3D-ED data with a resolution as low as ca. 3.78 Å. The generality of this strategy was further verified for different phases of COF-300. This study demonstrates a viable strategy for structure solution of COF materials from 3D-ED data of limited resolution, which may facilitate the discovery of new COF materials in the future. 相似文献
994.
Okba Al Rahal Colan E. Hughes P. Andrew Williams Andrew J. Logsdail Yael Diskin‐Posner Kenneth D. M. Harris 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(52):18964-18968
A new polymorph of l ‐tryptophan was prepared through crystallization from the gas phase, with structure determination carried out directly from powder XRD data augmented by periodic DFT‐D calculations. The new polymorph (denoted β) and the previously reported polymorph (denoted α) are both based on alternating hydrophilic and hydrophobic layers, but with substantially different hydrogen‐bonding arrangements. The β polymorph exhibits the energetically favourable l 2‐l 2 hydrogen‐bonding arrangement, which is unprecedented for amino acids with aromatic side chains. The specific molecular conformations adopted in the β polymorph facilitate this hydrogen‐bonding scheme while avoiding steric conflict of the side chains. 相似文献
995.
Frontispiece: Synthesis of Meso‐Substituted Subphthalocyanine–Subporphyrin Hybrids: Boron Subtribenzodiazaporphyrins 下载免费PDF全文
996.
Hughes C Liew M Sachdeva A Bassan P Dumas P Hart CA Brown MD Clarke NW Gardner P 《The Analyst》2010,135(12):3133-3141
It is hypothesized that cells with stem cell-like properties may be influential in carcinogenesis, possessing the ability to self-renew, produce differentiated daughter cells and resist environmental or therapeutic injury. This has led to a surge in interest in identifying and characterizing the tumour initiating or cancer stem cell (CSC) with the aim of discovering novel diagnostic and prognostic markers and of understanding the basic biology with the ultimate aim of generating new therapeutic approaches and biomarkers. However, a major hurdle to this process has been the lack of a truly specific cancer stem cell biomarker allied to the rarity of these cells. This has led to problems in characterising these CSCs by traditional '-omic' techniques. Using a renal carcinoma cell line model, we show that synchrotron radiation-Fourier transform infrared (SR-FTIR) spectroscopy is a suitable tool to measure discrete differences in the biochemistry of small numbers of single-cells. Using the chemometric techniques of Principal Component and Linear Discriminant Analysis (PCA and LDA) for multivariate reduction, biochemical differences between the cells from different sub-populations were evaluated. Results found lipid and phosphodiester vibrations to be particularly good discriminating markers in the spectra of these stem-like cells, relative to the more differentiated, proliferating cells that make up the majority of the cell population. 相似文献
997.
Two complexes [CuII(pbt)(dmf)Cl2] and [FeIII(pbt)Cl3], where pbt is 2-(2-pyridyl)benzothiazole, and dmf is dimethylformamide, were prepared by the reaction of metal chlorides
with pbt solutions. The structures of the products were identified by elemental analysis, usual spectroscopic methods and
X-ray diffraction analysis. The crystal data revealed penta-coordination around both metal ions, with trigonal bipyramidal
geometries. 2-(2-pyridyl)benzothiazole binds to both CuII and FeIII in the N,N-chelation manner and leaves the S atom uncoordinated. 相似文献
998.
The single crystal growth conditions and spectroscopic characterization of Ni-doped MgGa2O4 with inverse-spinel structure crystal family are described. Single crystals of this material have been grown by floating zone method. Ni-doped MgGa2O4 single crystals have broadband fluorescence in the 1100–1600 nm wavelength range, 1.6 ms room temperature lifetime, 56% quantum efficiency and stimulated emission cross section at the emission peak. This new material is very promising for tunable laser applications covering the important optical communication and eye safe wavelength region. 相似文献
999.
D. Keogh Z. Chen R. A. Hughes A. Dabkowski O. Marinov C. Maunders L. Gunawan M. J. Deen J. S. Preston G. A. Botton 《Applied Physics A: Materials Science & Processing》2010,98(1):187-194
The (100) surface of MgAl2O4 is evaluated as a substrate for the thin film deposition of the relaxor ferroelectric PbMg1/3Nb2/3O3(65%)–PbTiO3(35%). With a lattice mismatch of less than 0.5%, this film-substrate combination presents a geometrical template for growth
that is far superior to that formed with other commercially available oxide substrates. Films were deposited using the pulsed
laser deposition technique and were characterized in terms of their crystallographic, microstructural, and dielectric properties.
From a crystallographic perspective the films show excellent cube-on-cube epitaxy, are highly oriented, and show no evidence
of the frequently observed parasitic pyrochlore phase. With the exception of a few faceted surface structures, the film’s
microstructure is single-crystal-like, exhibiting a sharp film-substrate interface, a smooth top surface, and no discernable
granularity. The dielectric response shows the frequency-dependent diffuse phase transition characteristic of a relaxor material,
but with less frequency dispersion and a smaller maximum in the dielectric constant. Taken together, the results suggest that
the (100) MgAl2O4 substrate could prove to be an effective substrate material, not only for the PbMg1/3Nb2/3O3(65%)–PbTiO3(35%) system, but also for a number of other important lattice-matched ferroelectric, relaxor, and ferroelectric superlattice
systems. 相似文献
1000.
Thomas B. Scott Michelle Dickinson Richard A. Crane Olga Riba Gareth M. Hughes Geoffrey C. Allen 《Journal of nanoparticle research》2010,12(5):1765-1775
In order to increase the longevity of contaminant retention, a method is sought to improve the corrosion resistance of iron nanoparticles (INP) used for remediation of contaminated water and thereby extend their industrial lifetime. A multi-disciplinary approach was used to investigate changes induced by vacuum annealing (<5 × 10?8 mbar) at 500 °C on the bulk and surface chemistry of INP. The particle size did not change significantly as a result of annealing but the surface oxide thickness decreased from an average of 3–4 nm to 2 nm. BET analysis recorded a decrease in INP surface area from 19.0 to 4.8 m2 g?1, consistent with scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations which indicated the diffusion bonding of previously discrete particles at points of contact. X-ray diffraction (XRD) confirmed that recrystallisation of the metallic cores had occurred, converting a significant fraction of poorly crystalline iron to bcc α-Fe and Fe2B phases. X-ray photoelectron spectroscopy (XPS) indicated a change in the surface oxide stoichiometry from magnetite (Fe3O4) towards wüstite (FeO) and the migration of boron and carbon to the particle surfaces. The improved core crystallinity and the presence of passivating impurity phases at the INP surfaces may act to improve the corrosion resistance and reactive lifespan of the vacuum annealed INP for environmental applications. 相似文献