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101.
102.
Luca Cocconi Rosalba Garcia-Millan Zigan Zhen Bianca Buturca Gunnar Pruessner 《Entropy (Basel, Switzerland)》2020,22(11)
The rate of entropy production by a stochastic process quantifies how far it is from thermodynamic equilibrium. Equivalently, entropy production captures the degree to which global detailed balance and time-reversal symmetry are broken. Despite abundant references to entropy production in the literature and its many applications in the study of non-equilibrium stochastic particle systems, a comprehensive list of typical examples illustrating the fundamentals of entropy production is lacking. Here, we present a brief, self-contained review of entropy production and calculate it from first principles in a catalogue of exactly solvable setups, encompassing both discrete- and continuous-state Markov processes, as well as single- and multiple-particle systems. The examples covered in this work provide a stepping stone for further studies on entropy production of more complex systems, such as many-particle active matter, as well as a benchmark for the development of alternative mathematical formalisms. 相似文献
103.
104.
Oliver Strohmeier Silke Laßmann Bianca Riedel Daniel Mark Günter Roth Martin Werner Roland Zengerle Felix von Stetten 《Mikrochimica acta》2014,181(13-14):1681-1688
Point Mutations on the Kirsten rat sarcoma viral oncogene homolog (KRAS) have been identified as an important predictive biomarker for response to cancer therapy targeting the epidermal growth factor receptor. KRAS mutations are prevalent in up to 40 % of all colorectal carcinomas, and routinely conducted KRAS genotyping is becoming mandatory to predict therapy success and to reduce therapy costs. We report a low-cost, disposable and ready-to-use centrifugal microfluidic cartridge (termed GeneSlice) containing preloaded primers and probes. The GeneSlice cartridge enables the parallel detection of the seven most relevant KRAS point mutations by allele-specific real-time PCR. It represents a cost effective alternative to dideoxy-sequencing with a faster time-to-result (~ 2 h versus up to 20 h in case of dd-sequencing). Microfluidic processing of the GeneSlice along with allele-specific amplification and real-time detection are conducted in a slightly modified, commercially available PCR thermocycler. Intra-chip standard deviation of Cq values on the GeneSlices is negligible (GeneSlice 1: Cq,std.dev. = 0.13; GeneSlice 2: Cq,std.dev?=?0.26). In 23 of 24 experiments, the data for genotyping 6 cancer cell lines (n?=?4 per cell line) agreed with dd-sequencing. Additionally, DNA derived from microdissected formalin-fixed and paraffin embedded colorectal carcinomas of two cases was genotyped correctly and reproducibly (n?=?3 per patient; one GeneSlice excluded from evaluation). The GeneSlice therefore clearly demonstrated the potential to become a valuable tool for routine diagnostics of KRAS mutations by reducing costs and hands-on time. Figure
105.
Carlo Bianca 《Nonlinear Analysis: Hybrid Systems》2011,5(1):32-51
The highly complex nature of the transport in thermostatted billiards has been of interest in the last few decades because of industrial and medical applications. The onset of hyperbolic dynamics (deterministic chaos) in such a billiard has evidenced an interesting stabilization of the transport properties, especially in microporous media. Recently, different mathematical methods have been developed for establishing hyperbolicity in thermostatted billiards, among these, the Weyl-flow and the conformally symplectic structure techniques.This paper deals with analytical investigations on the possible hyperbolic nature of two thermostatted billiards: The nonequilibrium Ehrenfest gas (NEEG) and the pump model (PM). Despite numerical investigations supporting the idea of their dissipative dynamics, the hyperbolicity of these billiards has not been yet established. The analysis developed in this paper shows how the Weyl-flow technique has failed for NEEG, revealing the necessity to develop new strategies in order to obtain hyperbolicity. On the contrary, we prove that the PM has a conformally symplectic structure, which is the basis for establishing the hyperbolicity of such a hybrid dynamical system. 相似文献
106.
Christoph Bolli Janis Derendorf Prof. Dr. Carsten Jenne Dr. Harald Scherer Christian P. Sindlinger Bianca Wegener 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(42):13783-13792
The weakly coordinating anion [Me3NB12Cl11]? has been prepared by a simple two‐step procedure. The anion [Me3NB12Cl11]? is easily obtained in batches of up to 20 g by chlorination of the known [H3NB12H11]? anion with SbCl5 at about 190 °C and subsequent N‐methylation with methyl iodide. Starting from Na[Me3NB12Cl11], several synthetically useful salts with reactive cations ([NO]+, [Ph3C]+, and [(Et3Si)2H]+) were prepared. Full spectroscopic (NMR, IR, Raman, TGA, MS) characterization and single‐crystal X‐ray diffraction studies confirmed the identity and purity of the products. The thermal, chemical, and electrochemical stability as well as the basicity of the [Me3NB12Cl11]? anion is similar to that of the structurally related weakly coordinating 1‐carba‐closo‐dodecaborate and closo‐dodecaborate anions. The facile preparation of the [Me3NB12Cl11]? anion and its ideal chemical and physical properties make it a cheap alternative to other classes of weakly coordinating anions. 相似文献
107.
Gaetano Giammona Bianca Carlisi Salvatore Palazzo 《Journal of polymer science. Part A, Polymer chemistry》1987,25(10):2813-2818
Benzoic acid, acetylsalicylic acid, and 4-acetamidobenzoic acid have been covalently linked by ester bonds to α,β-poly(N-hydroxyethyl)-DL -aspartamide (PHEA), a water soluble and nontoxic polymer, in order to study PHEA as a drug carrier. 相似文献
108.
Sachinidis A Sotiriadou I Seelig B Berkessel A Hescheler J 《Combinatorial chemistry & high throughput screening》2008,11(1):70-82
Cell replacement therapy of severe degenerative diseases such as diabetes, myocardial infarction and Parkinson's disease through transplantation of somatic cells generated from embryonic stem (ES) cells is currently receiving considerable attention for the therapeutic applications. ES cells harvested from the inner cell mass (ICM) of the early embryo, can proliferate indefinitely in vitro while retaining the ability to differentiate into all somatic cells thereby providing an unlimited renewable source of somatic cells. In this context, identifying soluble factors, in particular chemically synthesized small molecules, and signal cascades involved in specific differentiation processes toward a defined tissue specific cell type are crucial for optimizing the generation of somatic cells in vitro for therapeutic approaches. However, experimental models are required allowing rapid and "easy-to-handle" parallel screening of chemical libraries to achieve this goal. Recently, the forward chemical genetic screening strategy has been postulated to screen small molecules in cellular systems for a specific desired phenotypic effect. The current review is focused on the progress of ES cell research in the context of the chemical genetics to identify small molecules promoting specific differentiation of ES cells to desired cell phenotype. Chemical genetics in the context of the cell ES-based cell replacement therapy remains a challenge for the near future for several scientific fields including chemistry, molecular biology, medicinal physics and robotic technologies. 相似文献
109.
We introduce and study a multi-valued integral of Aumann-type where the selectors are Gould integrals of real functions with
respect to finitely additive vector-valued measures. We also discuss the relationship between this kind of integral and the
M-Gould set-valued integral with respect to a finitely additive multimeasure M.
Received: November 17, 2006, Revised: September 17, 2007 and January, 8, 2008, Accepted: March 13, 2008. 相似文献
110.
Bray DJ Antonioli B Clegg JK Gloe K Gloe K Jolliffe KA Lindoy LF Wei G Wenzel M 《Dalton transactions (Cambridge, England : 2003)》2008,(13):1683-1685
A new metallo-capsule has been synthesised that consists of three copper(II) ions and two molecules of a tris-deprotonated tripodal ligand in which three 2,4-pentanedione groups are linked via their gamma-carbons through thioether spacers to the 1,3,5-positions of a triazine core. 相似文献