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991.
Laura Tblick Severien Van Keer Annemie De Smet Pierre Van Damme Michelle Laeremans Alejandra Rios Cortes Koen Beyers Vanessa Vankerckhoven Veerle Matheeussen Renee Mandersloot Arno Floore Chris J. L. M. Meijer Renske D. M. Steenbergen Alex Vorsters 《Molecules (Basel, Switzerland)》2021,26(7)
The potential of first-void (FV) urine as a non-invasive liquid biopsy for detection of human papillomavirus (HPV) DNA and other biomarkers has been increasingly recognized over the past decade. In this study, we investigated whether the volume of this initial urine stream has an impact on the analytical performance of biomarkers. In parallel, we evaluated different DNA extraction protocols and introduced an internal control in the urine preservative. Twenty-five women, diagnosed with high-risk HPV, provided three home-collected FV urine samples using three FV urine collection devices (Colli-Pee) with collector tubes that differ in volume (4, 10, 20 mL). Each collector tube was prefilled with Urine Conservation Medium spiked with phocine herpesvirus 1 (PhHV-1) DNA as internal control. Five different DNA extraction protocols were compared, followed by PCR for GAPDH and PhHV-1 (qPCR), HPV DNA, and HBB (HPV-Risk Assay), and ACTB (methylation-specific qPCR). Results showed limited effects of collection volume on human and HPV DNA endpoints. In contrast, significant variations in yield for human endpoints were observed for different DNA extraction methods (p < 0.05). Additionally, the potential of PhHV-1 as internal control to monitor FV urine collection, storage, and processing was demonstrated. 相似文献
992.
Jian‐Gong Yang Kai Li Jian Wang Shanshan Sun Weijie Chi Chao Wang Xiaoyong Chang Chao Zou Wai‐Pong To Ming‐De Li Xiaogang Liu Wei Lu Hong‐Xing Zhang Chi‐Ming Che Yong Chen 《Angewandte Chemie (International ed. in English)》2020,59(17):6915-6922
Materials exhibiting excitation wavelength‐dependent photoluminescence (Ex‐De PL) in the visible region have potential applications in bioimaging, optoelectronics and anti‐counterfeiting. Two multifunctional, chiral [Au(NHC)2][Au(CN)2] (NHC=(4R,5R)/(4S,5S)‐1,3‐dimethyl‐4,5‐diphenyl‐4,5‐dihydro‐imidazolin‐2‐ylidene) complex double salts display Ex‐De circularly polarized luminescence (CPL) in doped polymer films and in ground powder. Emission maxima can be dynamically tuned from 440 to 530 nm by changing the excitation wavelength. The continuously tunable photoluminescence is proposed to originate from multiple emissive excited states as a result of the existence of varied AuI???AuI distances in ground state. The steric properties of the NHC ligand are crucial to the tuning of AuI???AuI distances. An anti‐counterfeiting application using these two salts is demonstrated. 相似文献
993.
A Flexible Photoactive Titanium Metal–Organic Framework Based on a [TiIV3(μ3‐O)(O)2(COO)6] Cluster 下载免费PDF全文
Bart Bueken Dr. Frederik Vermoortele Dr. Danny E. P. Vanpoucke Dr. Helge Reinsch Dr. Chih‐Chin Tsou Dr. Pieterjan Valvekens Dr. Trees De Baerdemaeker Prof. Dr. Rob Ameloot Prof. Dr. Christine E. A. Kirschhock Prof. Dr. Veronique Van Speybroeck Prof. Dr. James M. Mayer Prof. Dr. Dirk De Vos 《Angewandte Chemie (International ed. in English)》2015,54(47):13912-13917
The synthesis of titanium–carboxylate metal–organic frameworks (MOFs) is hampered by the high reactivity of the commonly employed alkoxide precursors. Herein, we present an innovative approach to titanium‐based MOFs by the use of titanocene dichloride to synthesize COK‐69, the first breathing Ti MOF, which is built up from trans‐1,4‐cyclohexanedicarboxylate linkers and an unprecedented [TiIV3(μ3‐O)(O)2(COO)6] cluster. The photoactive properties of COK‐69 were investigated in depth by proton‐coupled electron‐transfer experiments, which revealed that up to one TiIV center per cluster can be photoreduced to TiIII while preserving the structural integrity of the framework. The electronic structure of COK‐69 was determined by molecular modeling, and a band gap of 3.77 eV was found. 相似文献
994.
Fengxiang Li Junlin Xie De Fang Feng He Kai Qi Pijun Gong 《Research on Chemical Intermediates》2017,43(10):5413-5432
A series of Ce–MnO x /TiO2 catalysts were prepared using a novel sol–gel template method and investigated for low-temperature selective catalytic reduction (SCR) of NO with NH3 at temperatures ranging from 353 to 473 K. The 0.07Ce–MnO x /TiO2 catalyst showed the highest activity and best resistance to SO2 poisoning. The structure and properties of the catalysts were characterized using X-ray diffraction (XRD) analysis, thermogravimetric analysis (TGA), thermogravimetry (TG)–differential scanning calorimetry (DSC)–mass spectroscopy (MS), high-resolution transmission electron microscopy (HRTEM), Brunauer–Emmett–Teller (BET) measurements, H2-temperature-programmed reduction (TPR), and NH3-temperature-programmed desorption (TPD). The superior catalytic activity of the 0.07Ce–MnO x /TiO2 catalyst was probably due to a change in the active components, an increase in surface active oxygen and surface acid sites, and lower crystallinity and larger surface area with Ce doping. Furthermore, the reduction ability also became stronger. The SO2 poisoning resistance of the 0.07Ce–MnO x /TiO2 catalyst improved because doping with Ce can effectively decrease the formation of ammonium salt on the catalyst surface and the sulfation of MnO x . In situ diffuse-reflectance infrared Fourier-transform (DRIFT) spectroscopy experiments indicated that addition of Ce could promote adsorption of NH3 and inhibit generation of some nitryl species. The SCR reactions over the catalysts mainly followed the Eley–Rideal mechanism accompanied with a partial Langmuir–Hinshelwood mechanism. 相似文献
995.
采用氧化沉淀-浸渍法制备了不同含量Fe掺杂的Fe-Mn/TiO2低温脱硝催化剂,考察了催化剂在80~180 ℃范围内的脱硝能力并通过XRD、BET、TG、H2-TPR、NH3-TPD等测试手段,对催化剂的物理化学性质进行了表征.实验结果表明,Fe的加入并没有改变Mn/TiO2的主要晶相,仍是锐钛矿型的TiO2,MnOx和FeOx均以非晶态结构高度分散于载体表面,而且Fe的加入可以有效地改善催化剂的微观形貌、比表面积及表面酸性位点,从而提高其低温脱硝性能.Fe掺量在Fe/Ti为0.10时催化剂具有最佳性能,在120 ℃时脱硝率可达90;以上. 相似文献
996.
997.
A. Agnello E. De Pauw P. Natalis 《Journal of the American Society for Mass Spectrometry》1993,4(4):312-321
Department of General and Physical Chemistry, University of Liege, Liege, Belgium A specific beam-induced secondary reaction involving the condensation of hydroxylic matrices with some organic groups (aldehydes, ketones, etc.) accompanied by the loss of a water molecule was investigated by liquid secondary ion mass spectrometry/fast-atom bombardment (LSIMS/FAB). A mechanistic scheme and a structure of the induced product are proposed. The features of this secondary reaction were studied and the influence of the types of solutes, acidic additives, and matrices analyzed. Rather than a drawback, LSIMS/FAB mass spectrometry can take advantage of this matrix effect to infer analytical information through tandem mass spectrometry experiments. Specific neutral loss scans can be conducted to highlight beam-induced reactive molecules, even when the detection of these species is prevented in normal scan spectra by other surface-active components. 相似文献
998.
A time-resolved fluorescence spectrometer with laser excitation and picosecond time-correlated single photon counting detection is described. The parameter recovery from experimental data is discussed in detail. Correction methods for errors in the time-correlated single photon counting technique are indicated. Applications of this photophysical tool to polymer research are given. 相似文献
999.
By means of the jet-bundle formalism, the Second Noether Theorem is formulated for a general first-order Lagrangian field theory with infinitesimal local symmetries. These symmetries are implemented by a linear differential operator acting between the sections of a vector bundle and vector fields on the configuration bundle. The problem of the degeneration of the Lagrangian system is examined from a covariant and an instantaneous (i.e. space+time split) viewpoint. It is shown that in the instantaneous approach the presence of infinitesimal local symmetries leads to degeneration of the theory. Vertical local symmetries are shown to imply degeneration also in the covariant formalism. These results can be extended to higher-order Lagrangians as well. 相似文献
1000.
In vivo 1H-NMR procedure to determine several rat cerebral metabolite levels simultaneously, undisturbed by water and lipid signals 总被引:1,自引:0,他引:1
Methods developed for in vivo 1H-NMR spectroscopy are evaluated and applied using conscious rats. Good quality 1H-spectra of the brain are obtained using a surface coil and a spin echo pulse sequence with the binomial 1-1 and 2-2 water suppression pulses. However, comparing spectra from various rats with each other the water and lipid signals, which cause spectral overlap problems, may differ while the other spectral peaks agree well. Spatially one- and two-dimensional 1H spectroscopic imaging of the rat brain shows that the former signals stem from distinct spatial regions localized close to the rf coil. From a spectroscopic image, a spectrum over a limited spatial region is constructed in which the water signals are strongly reduced, the lipid signals are eliminated and lactic acid can be observed clearly simultaneously with other metabolites. 相似文献