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41.
This review provides an overview of the progress made by computational and systems biologists in characterizing different cell death regulatory mechanisms that constitute the cell death network. We define the cell death network as a comprehensive decision-making mechanism that controls multiple death execution molecular circuits. This network involves multiple feedback and feed-forward loops and crosstalk among different cell death-regulating pathways. While substantial progress has been made in characterizing individual cell death execution pathways, the cell death decision network is poorly defined and understood. Certainly, understanding the dynamic behavior of such complex regulatory mechanisms can be only achieved by applying mathematical modeling and system-oriented approaches. Here, we provide an overview of mathematical models that have been developed to characterize different cell death mechanisms and intend to identify future research directions in this field.  相似文献   
42.
Journal of Solid State Electrochemistry - Development of high-performance energy storage devices is a vital research area to meet the present-day energy demand. In the work carried toward the...  相似文献   
43.
The stuffed tridymite structure Ba(Zn/Co)1−xSi1−xM2xO4 (M=Al3+ and Fe3+) is explored for the possible multiferroic behavior and to develop new inorganic colored materials. The compounds were synthesized by employing conventional solid-state chemistry methods in the temperature range 1100–1175 °C for 24 h. The powder X-ray diffraction (PXRD) and Rietveld refinement studies indicate that the compounds stabilize in the P63 space group (no. 173). The refinement results were also rationalized by employing Raman spectroscopic studies. The compounds were found to be second harmonic generation (SHG) active and show weak ferroelectric behavior. The co-substitution of Co2+ and Fe3+ in the structure gives rise to a weak ferromagnetic behavior to the compound, BaCo0.75Si0.75Fe0.5O4, making it a multiferroic material. The optical studies on the prepared compounds exhibited blue color (Co2+ in Td geometry), purple color (Ni2+ in Td geometry), and simultaneous substitution of Co2+ and Fe3+ gives rise to blue-green color owing to metal-to-metal charge transfer (MMCT) effect.  相似文献   
44.
In this work, the electrocatalytic reduction of dichloromethane (CH2Cl2) into hydrocarbons involving a main group element-based molecular triazole-porphyrin electrocatalyst H2PorT8 is reported. This catalyst converted CH2Cl2 in acetonitrile to various hydrocarbons (methane, ethane, and ethylene) with a Faradaic efficiency of 70 % and current density of −13 mA cm−2 at a potential of −2.2 V vs. Fc/Fc+ using water as a proton source. The findings of this study and its mechanistic interpretations demonstrated that H2PorT8 was an efficient and stable catalyst for the hydrodechlorination of CH2Cl2 and that main group catalysts could be potentially used for exploring new catalytic reaction mechanisms.  相似文献   
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It is proved that a so called novel nonlinear optical glycine barium nitrate potassium nitrate single crystal grown by slow evaporation solution growth technique by Ravishankar et al. (Optik, 2013) is actually the well-known γ-glycine crystal.  相似文献   
48.
A method is presented to relate local morphology and ionic conductivity in a solid, lamellar block copolymer electrolyte for lithium batteries, by simulating conductivity through transmission electron micrographs. The electrolyte consists of polystyrene‐block‐poly(ethylene oxide) mixed with lithium bis(trifluoromethanesulfonyl) imide salt (SEO/LiTFSI), where the polystyrene phase is structural phase and the poly(ethylene oxide)/LiTFSI phase is ionically conductive. The electric potential distribution is simulated in binarized micrographs by solving the Laplace equation with constant potential boundary conditions. A morphology factor, f, is reported for each image by calculating the effective conductivity relative to a homogenous conductor. Images from two samples are examined, one annealed with large lamellar grains and one unannealed with small grains. The average value of f is 0.45 ± 0.04 for the annealed sample, and 0.37 ± 0.03 for the unannealed sample, both close to the value predicted by effective medium theory, 1/2. Simulated conductivities are compared to published experimental conductivities. The value of fUnannealed/fAnnealed is 0.82 for simulations and 6.2 for experiments. Simulation results correspond well to predictions by effective medium theory but do not explain the experimental measurements. Observation of nanoscale morphology over length scales greater than the size of the micrographs (~1 μm) may be required to explain the experimental results. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 266–274  相似文献   
49.
The ligand salt, Me6[14]diene·2HClO4 (L·2HClO4) was prepared by condensation of acetone and ethylene diamine in the presence of perchloric acid. On reduction of this diene ligand salt, L·2HClO4 with sodium borohydride, the two isomeric ligands, ‘tet-a’ and ‘tet-b’ were produced. The ligands, on reaction with ZnX2 (X=Cl, ClO4, NO3 or CH3COO) and ZnSO4 produced the corresponding complexes. These complexes have been characterized on the basis of elemental analyses; IR, UV–Vis and 1H-NMR spectroscopies; magnetic and conductance data. Based on these data, all of the complexes of the diene ligand L, as well as the perchlorate complexes of all of the ligands attained a square-pyramidal arrangement, whereas the complexes of ‘tet-a’ and ‘tet-b’, with X=NO3, Cl or CH3COO and with ZnSO4 salt, were octahedral. Moreover, all complexes were monometallic except the nitrato complex, [(ZnL)2(µ-NO3)](ClO4)3 which is bimetallic. The structure of [(ZnL)2(µ-NO3)](ClO4)3 has been confirmed by X-ray crystallography. In this complex the zinc centres lie within a N4O donor set, with the four nitrogen donors from L and one of the oxygen atom stemming from the bridging NO3. The complexes show different electrolytic behavior in different solvents. The antibacterial activities of the ligands and complexes towards different phytopathogenic bacteria have been investigated.  相似文献   
50.
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