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831.
Zhen-HuaDuan MaciejKoutny 《计算机科学技术学报》2004,19(3):0-0
We discuss the projection temporal logic (PTL), based on a primitive projection operator, prj. A framing technique is also presented, using which a synchronization operator, await, is defined within the underlying logic. A framed temporal logic programming language (FTLL) is presented. To illustrate how to use both the language and framing technique, some examples are given. 相似文献
832.
Katarzyna Ratajczak Karolina Sklodowska-Jaros Ewelina Kalwarczyk Jacek A. Michalski Slawomir Jakiela Magdalena Stobiecka 《International journal of molecular sciences》2022,23(15)
Novel high-performance biosensing devices, based on a microporous cellulose matrix, have been of great interest due to their high sensitivity, low cost, and simple operation. Herein, we report on the design and testing of portable paper-based immunostrips (IMS) for in-field blood typing in emergencies requiring blood transfusion. Cellulose fibrils of a paper membrane were functionalized with antibodies via supramolecular interactions. The formation of hydrogen bonds between IgM pentamer and cellulose fibers was corroborated using quantum mechanical calculations with a model cellulose chain and a representative amino acid sequence. In the proposed immunostrips, paper with a pore size of 3 µm dia. was used to enable functionalization of its channels with antibody molecules while blocking the red blood cells (RBC) from channel entering. Under the optimized test conditions, all blood types of AB0 and Rh system could be determined by naked eye examination, requiring only a small blood sample (3.5 µL). The durability of IgM immunostrips against storing has been tested. A new method of statistical evaluation of digitized blood agglutination images, compatible with a clinical five-level system, has been proposed. Critical parameters of the agglutination process have been established to enable future development of automatic blood typing with machine vision and digital data processing. 相似文献
833.
Jingyi Tian Giorgio Adamo Hailong Liu Mengfei Wu Maciej Klein Jie Deng Norman Soo Seng Ang Ramón Paniagua-Domínguez Hong Liu Arseniy I. Kuznetsov Cesare Soci 《Advanced materials (Deerfield Beach, Fla.)》2023,35(1):2207430
Metasurfaces supporting optical bound states in the continuum (BICs) are emerging as simple and compact optical cavities to realize polarization-vortex lasers. The winding of the polarization around the singularity defines topological charges which are generally set by the cavity design and cannot be altered without changing geometrical parameters. Here, a subwavelength-thin phase-change halide perovskite BIC metasurface functioning as a tunable polarization vortex microlaser is demonstrated. Upon the perovskite structural phase transitions, both its refractive index and gain vary substantially, inducing reversible and bistable switching between distinct polarization vortexes underpinned by opposite topological charges. Dynamic tuning and switching of the resulting vector beams may find use in microscopy imaging, particle trapping and manipulation, and optical data storage. 相似文献
834.
Danis I. Badrtdinov Carlos Rodriguez-Fernandez Magdalena Grzeszczyk Zhizhan Qiu Kristina Vaklinova Pengru Huang Alexander Hampel Kenji Watanabe Takashi Taniguchi Lu Jiong Marek Potemski Cyrus E. Dreyer Maciej Koperski Malte Rösner 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(41):2300144
A key advantage of utilizing van-der-Waals (vdW) materials as defect-hosting platforms for quantum applications is the controllable proximity of the defect to the surface or the substrate allowing for improved light extraction, enhanced coupling with photonic elements, or more sensitive metrology. However, this aspect results in a significant challenge for defect identification and characterization, as the defect's properties depend on the the atomic environment. This study explores how the environment can influence the properties of carbon impurity centers in hexagonal boron nitride (hBN). It compares the optical and electronic properties of such defects between bulk-like and few-layer films, showing alteration of the zero-phonon line energies and their phonon sidebands, and enhancements of inhomogeneous broadenings. To disentangle the mechanisms responsible for these changes, including the atomic structure, electronic wavefunctions, and dielectric screening, it combines ab initio calculations with a quantum-embedding approach. By studying various carbon-based defects embedded in monolayer and bulk hBN, it demonstrates that the dominant effect of the change in the environment is the screening of density–density Coulomb interactions between the defect orbitals. The comparative analysis of experimental and theoretical findings paves the way for improved identification of defects in low-dimensional materials and the development of atomic scale sensors for dielectric environments. 相似文献
835.
Eva Miglbauer Dr. Oliya S. Abdullaeva Dr. Maciej Gryszel Dr. Eric Daniel Głowacki 《Chembiochem : a European journal of chemical biology》2023,24(17):e202300353
Reactive oxygen species (ROS) are an integral part of many anticancer therapies. Fenton-like processes involving reactions of peroxides with transition metal ions are a particularly potent and tunable subset of ROS approaches. Precise on-demand dosing of the Fenton reaction is an area of great interest. Herein, we present a concept of an electrochemical faradaic pixel that produces controlled amounts of ROS via a Fenton-like process. The pixel comprises a cathode and anode, where the cathode reduces dissolved oxygen to hydrogen peroxide. The anode is made of chromium, which is electrochemically corroded to yield chromium ions. Peroxide and chromium interact to form a highly oxidizing mixture of hydroxyl radicals and hexavalent Cr ions. After benchmarking the electrochemical properties of this type of device, we demonstrate how it can be used under in vitro conditions with a cancer cell line. The faradaic Fenton pixel is a general and scalable concept that can be used for on-demand delivery of redox-active products for controlling a physiological outcome. 相似文献
836.
Izabela Siekierska Dr. Maciej Lukaszewicz Dr. Remigiusz Worch Prof. Marzena Jankowska-Anyszka Dr. Karolina Piecyk 《ChemMedChem》2023,18(4):e202200490
Aryloxy triester phosphoramidate methodology, commonly known as ProTide technology, is one of the most widely used prodrug approaches applied to therapeutic nucleosides. This approach has been used extensively by the pharmaceutical industry and researchers in medicinal chemistry. Herein we report our adaptation of this effective method for the synthesis of bioactive 5’-mRNA cap analogues as inhibitors for targeting cap-dependent translation. The synthesis was performed in two main stages: preparation of N2-modified guanosine analogues and their subsequent transformation into prodrugs using phenylethoxy-l -alaninyl phosphorochloridate. The prepared pro-nucleotide cap analogues were tested for their capacity in enzymatic activation, inhibitory properties in a rabbit reticulocyte lysate system, and passive membrane translocation properties. 相似文献