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91.
Although critical for development of novel therapies, understanding altered lung function in disease models is challenging because the transport and diffusion of gases over short distances, on which proper function relies, is not readily visualized. In this review we summarize progress introducing hyperpolarized 129Xe imaging as a method to follow these processes in vivo. The work is organized in sections highlighting methods to observe the gas replacement effects of breathing (Gas Dynamics during the Breathing Cycle) and gas diffusion throughout the parenchymal airspaces (3). We then describe the spectral signatures indicative of gas dissolution and uptake (4), and how these features can be used to follow the gas as it enters the tissue and capillary bed, is taken up by hemoglobin in the red blood cells (5), re-enters the gas phase prior to exhalation (6), or is carried via the vasculature to other organs and body structures (7). We conclude with a discussion of practical imaging and spectroscopy techniques that deliver quantifiable metrics despite the small size, rapid motion and decay of signal and coherence characteristic of the magnetically inhomogeneous lung in preclinical models (8). 相似文献
92.
Sarva Jit Singh Neelam Sachdeva Sandhya Khurana 《Proceedings Mathematical Sciences》1999,109(4):417-423
The dispersion equation for Love waves in a monoclinic elastic layer of uniform thickness overlying a monoclinic elastic half-space
is derived by applying the traction-free boundary condition at the surface and continuity conditions at the interface. The
dispersion curves showing the effect of anisotropy on the calculated phase velocity are presented. The special cases of orthotropic
and transversely isotropic media are also considered. It is shown that the well-known dispersion equation for Love waves in
an isotropic layer overlying an isotropic half-space follows as a particular case. 相似文献
93.
94.
We calculate the ordinal L p index defined in [3] for Rosenthal’s space X p , \({\ell_p}\) and \({\ell_2}\). We show that an infinite-dimensional subspace of L p \({(2 < p < \infty)}\) non-isomorphic to \({\ell_2}\) embeds in \({\ell_p}\) if and only if its ordinal index is the minimal possible. We also give a sufficient condition for a \({\mathcal{L}_p}\) subspace of \({\ell_p \oplus \ell_2}\) to be isomorphic to X p . 相似文献
95.
Coaxial metal and magnetic alloy nanotubes in polycarbonate templates by electroless deposition 总被引:1,自引:0,他引:1
James F. Rohan Declan P. Casey Bernadette M. Ahern Fernando M.F. Rhen Saibal Roy David Fleming Simon E. Lawrence 《Electrochemistry communications》2008,10(9):1419-1422
We present a novel technique for the preparation of coaxial metal and magnetic alloy nanotubes, which is demonstrated for the coaxial nanotubes of Ni/Co and Ni/CoNiFe alloys deposited in activated polycarbonate templates using electroless plating. For each metal or alloy the tube wall thickness was controlled to be less than 100 nm. The process involved two consecutive deposition steps from hypophosphite and/or borane reducing agent based electroless plating solutions. We further characterise the magnetic properties of the ternary magnetic alloy films and coaxial nanotubes. The coaxial tubes show homogenous wall thickness and composition, which is delineated from the magnetic measurements. 相似文献
96.
Yao Liu Cheng-Cheng Bi Qian-Xin Bao Rohan Weerasooriya Xing Chen 《Electroanalysis》2023,35(5):e202200493
A highly efficient electrode material, three-dimensional reduced graphene oxide with varying wrinkles and folds (WRGO), applicable for electrochemical determination of Hg(II) was obtained by treating graphene oxide (GO) with KOH aqueous solution. After alkaline etching, the relatively flat graphene was altered and its self-aggregation was significantly alleviated, producing more wrinkles and folds, which provided more active adsorption sites for heavy metal ions. WRGO-5 modified electrode system herein offers a highest sensitivity of (31.83 μAμM−1) and a lowest LOD of (16.28 nM). Moreover, the electrode sensor possesses good stability and reproducibility. 相似文献
97.
A novel synthesis of 2-substituted 2H-imidazo[1,5-b]isoquinoline-1,5-diones by reductive desulfurization of a variety of 2-substituted
3-thioxo-2H-imidazo[1,5-b]isoquinoline-1,5-diones is reported with nickel boride in dry methanol at ambient temperature.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 404–408, March, 2008. 相似文献
98.
Parallel solution-phase chemistry has yielded a series of secondary amide analogues of the fungal natural product 3-chloro-4-hydroxyphenylacetamide. 3-Chloro-4-hydroxyphenylacetic acid was coupled to a variety of primary amines using 1-ethyl-3-(3'-dimethylamino- propyl)-carbodiimide hydrochloride. The desired products were obtained in good yield and high purity following rapid silica purification. All analogues were spectroscopically characterised using NMR, UV, IR and MS data. One compound displayed moderate cytotoxicity against the human melanoma and prostate cell lines, MM96L and DU145. 相似文献
99.
Aurora Diamante Piyush K. Chaturbedy Pamela J. E. Rowling Janet R. Kumita Rohan S. Eapen Stephen H. McLaughlin Marc de la Roche Albert Perez-Riba Laura S. Itzhaki 《Chemical science》2021,12(3):880
Here we exploit the simple, ultra-stable, modular architecture of consensus-designed tetratricopeptide repeat proteins (CTPRs) to create a platform capable of displaying both single as well as multiple functions and with diverse programmable geometrical arrangements by grafting non-helical short linear binding motifs (SLiMs) onto the loops between adjacent repeats. As proof of concept, we built synthetic CTPRs to bind and inhibit the human tankyrase proteins (hTNKS), which play a key role in Wnt signaling and are upregulated in cancer. A series of mono-valent and multi-valent hTNKS binders was assembled. To fully exploit the modular scaffold and to further diversify the multi-valent geometry, we engineered the binding modules with two different formats, one monomeric and the other trimeric. We show that the designed proteins are stable, correctly folded and capable of binding to and inhibiting the cellular activity of hTNKS leading to downregulation of the Wnt pathway. Multivalency in both the CTPR protein arrays and the hTNKS target results in the formation of large macromolecular assemblies, which can be visualized both in vitro and in the cell. When delivered into the cell by nanoparticle encapsulation, the multivalent CTPR proteins displayed exceptional activity. They are able to inhibit Wnt signaling where small molecule inhibitors have failed to date. Our results point to the tremendous potential of the CTPR platform to exploit a range of SLiMs and assemble synthetic binding molecules with built-in multivalent capabilities and precise, pre-programmed geometries. 相似文献
100.
de Oliveira Maida Aysla Costa Ficca Valerio C. A. Gokhale Rohan Santoro Carlo Mecheri Barbara D’Epifanio Alessandra Licoccia Silvia Atanassov Plamen 《Journal of Solid State Electrochemistry》2021,25(1):93-104
Journal of Solid State Electrochemistry - In this work, we initially report a detailed advancement in the utilization of metal-N4 chelate macrocycles in the oxygen reduction reaction (ORR). Then,... 相似文献