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21.
Radioanalytical techniques are used in this work to investigate the extraction behaviour with TBP of rhodium (III) chloride
solutions to which a large excess of iodide is added. Extraction yields and distribution coefficients are determined as a
function of HClO4 or H2SO4 content in the aqueous phase. Rhodium-stripping from the organic phase with ammonia solutions is also tested. 相似文献
22.
L. Di Piazza C. Maniscalco T. Marino 《Rendiconti del Circolo Matematico di Palermo》1979,28(1):134-142
Let μ be a diffuse Carathéodory measure. The purpose of this paper is to prove that, for every open setU inR, μ(·∩U) is a Carathéodory measure too. 相似文献
23.
Phase separation in cell membranes promotes the assembly of transmembrane receptors to initiate signal transduction in response to environmental cues. Many cellular behaviors are manipulated by promoting membrane phase separation through binding to multivalent extracellular ligands. However, available extracellular molecule tools that enable manipulating the clustering of transmembrane receptors in a controllable manner are rare. In the present study, we report a DNA nanodevice that enhances membrane phase separation through the clustering of dynamic lipid rafts. This DNA nanodevice is anchored in the lipid raft region of the cell membrane and initiated by ATP. In a tumor microenvironment, this device could be activated to form a long DNA duplex on the cell membrane, which not only enhances membrane phase separation, but also blocks the interaction between the transmembrane surface adhesion receptor and extracellular matrix, leading to reduced migration. We demonstrate that the ATP-activated DNA nanodevice could inhibit cancer cell migration both in vitro and in vivo. The concept of using DNA to regulate membrane phase separation provides new possibilities for manipulating versatile cell functions through rational design of functional DNA structures.A DNA nanodevice is developed to enhance the cell membrane phase separation in a tumor microenvironment to weaken the formation of focal adhesion. As a result, the migration of cancer cells is inhibited both in vitro and in vivo. 相似文献
24.
Leqing Lin Yu Zhong Haoyang Lin Chenglong Wang Zhifei Yang Qian Wu Di Zhang Wenguo Zhu Yongchun Zhong Yuwei Pan Jianhui Yu Huadan Zheng 《Molecules (Basel, Switzerland)》2022,27(13)
Spider silk is one of the hottest biomaterials researched currently, due to its excellent mechanical properties. This work reports a novel humidity sensing platform based on a spider silk-modified quartz tuning fork (SSM-QTF). Since spider silk is a kind of natural moisture-sensitive material, it does not demand additional sensitization. Quartz-enhanced conductance spectroscopy (QECS) was combined with the SSM-QTF to access humidity sensing sensitively. The results indicate that the resonance frequency of the SSM-QTF decreased monotonously with the ambient humidity. The detection sensitivity of the proposed SSM-QTF sensor was 12.7 ppm at 1 min. The SSM-QTF sensor showed good linearity of ~0.99. Using this sensor, we successfully measured the humidity of disposable medical masks for different periods of wearing time. The results showed that even a 20 min wearing time can lead to a >70% humidity in the mask enclosed space. It is suggested that a disposable medical mask should be changed <2 h. 相似文献
25.
Xin Meng Jinqing Li Xiaoqiang Di Yaohui Sheng Donghua Jiang 《Entropy (Basel, Switzerland)》2022,24(7)
Today, with the rapid development of the Internet, improving image security becomes more and more important. To improve image encryption efficiency, a novel region of interest (ROI) encryption algorithm based on a chaotic system was proposed. First, a new 1D -cos-cot (1D-ECC) with better chaotic performance than the traditional chaotic system is proposed. Second, the chaotic system is used to generate a plaintext-relate keystream based on the label information of a medical image DICOM (Digital Imaging and Communications in Medicine) file, the medical image is segmented using an adaptive threshold, and the segmented region of interest is encrypted. The encryption process is divided into two stages: scrambling and diffusion. In the scrambling stage, helical scanning and index scrambling are combined to scramble. In the diffusion stage, two-dimensional bi-directional diffusion is adopted, that is, the image is bi-directionally diffused row by column to make image security better. The algorithm offers good encryption speed and security performance, according to simulation results and security analysis. 相似文献
26.
Martina Bortolami Paola Di Matteo Daniele Rocco Marta Feroci Rita Petrucci 《Molecules (Basel, Switzerland)》2022,27(15)
Agropyron repens (L.) P. Beauv. (couch grass) is a world-wide infesting rhizomatous plant with pharmacological applications. Chemical research is focused on its allelopathic and anti-inflammatory components, which are mainly present in the essential oil. Conversely, the aqueous extracts have been sparingly investigated, although the herbal tea is by far the most used formulation. To fill the gap, the metabolic profile of Agropyron repens rhizome herbal tea was investigated by electrospray ionization (ESI) tandem–mass spectrometry (MS/MS); the phenolic profile was investigated by HPLC-PDA-ESI-MS/MS. ESI-MS fingerprinting was provided, evidencing diagnostic ions for saccharides, organic acids and amino acids. The HPLC-PDA-ESI-MS/MS analysis evidenced at least 20 characteristic phenolic compounds, the most representative being caffeoyl and feruloyl quinic esters, followed by coumaric, caffeic and ferulic acids, and hesperidin among flavonoids. In addition, the essential amino acid tryptophan was identified for the first time. The results suggest new perspectives of applications for Agropyron repens rhizome. 相似文献
27.
Valentina Noemi Madia Walter Toscanelli Daniela De Vita Marta De Angelis Antonella Messore Davide Ialongo Luigi Scipione Valeria Tudino Felicia Diodata DAuria Roberto Di Santo Stefania Garzoli Annarita Stringaro Marisa Colone Magda Marchetti Fabiana Superti Lucia Nencioni Roberta Costi 《Molecules (Basel, Switzerland)》2022,27(12)
Influenza viruses are transmitted from human to human via airborne droplets and can be transferred through contaminated environmental surfaces. Some works have demonstrated the efficacy of essential oils (EOs) as antimicrobial and antiviral agents, but most of them examined the liquid phases, which are generally toxic for oral applications. In our study, we describe the antiviral activity of Citrus bergamia, Melaleuca alternifolia, Illicium verum and Eucalyptus globulus vapor EOs against influenza virus type A. In the vapor phase, C. bergamia and M. alternifolia strongly reduced viral cytopathic effect without exerting any cytotoxicity. The E. globulus vapor EO reduced viral infection by 78% with no cytotoxicity, while I. verum was not effective. Furthermore, we characterized the EOs and their vapor phase by the head-space gas chromatography–mass spectrometry technique, observing that the major component found in each liquid EO is the same one of the corresponding vapor phases, with the exception of M. alternifolia. To deepen the mechanism of action, the morphological integrity of virus particles was checked by negative staining transmission electron microscopy, showing that they interfere with the lipid bilayer of the viral envelope, leading to the decomposition of membranes. We speculated that the most abundant components of the vapor EOs might directly interfere with influenza virus envelope structures or mask viral structures important for early steps of viral infection. 相似文献
28.
The European Physical Journal C - Numerical Stochastic Perturbation Theory was able to get three- (and even four-) loop results for finite Lattice QCD renormalization constants. More recently, a... 相似文献
29.
30.
Giovanni Di Nicola Cristiano Di Nicola Matteo Moglie Marco Pacetti 《Journal of Thermal Analysis and Calorimetry》2012,108(2):621-625
This study presents a new formula for the surface tension prediction of alkenes. As a first step, an analysis of the available data of the experimental surface tension data for alkenes was performed. The experimental data were collected, after a careful literature survey, for the following pure fluids: propene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-tetradecene, and 1-pentadecene. Then, the experimental data were regressed with the most reliable semi-empirical correlating methods based on the corresponding state theory existing in the literature. As a final step, an analysis of the available data of the experimental surface tension data for alkenes was performed starting from the two recently proposed equations for the prediction of the surface tension of refrigerants based on the corresponding states principle. To minimize the deviation between the predicted data and the experimental data and to find the optimal equation coefficients for experimental data regression, a (μ + λ)-evolution strategy was adopted. The analysis showed that the equation that gave the best results for the prediction of the surface tension of alkenes was the one with a very limited number of parameters. The finally proposed equation is very simple and gives a noticeable improvement with respect to the existing equations. It is based on the corresponding state principle, containing the acentric factor, the critical temperature, and pressure. 相似文献