We report on the demonstration of a high finesse micro-optomechanical system and identify potential applications ranging from optical cooling to weak force detection to massive quantum superpositions. The system consists of a high quality diameter flat dielectric mirror cut from a larger substrate with a focused ion beam and attached to an atomic force microscope cantilever. Cavity ring-down measurements performed on a 25 mm long Fabry-Pérot cavity with the 30 microm mirror at one end show an optical finesse of 2100. Numerical calculations show that the finesse is not diffraction limited and that orders of magnitude higher finesse should be possible. A mechanical quality factor of more than 10(5) at pressures below 10(-3) mbar is demonstrated for the cantilever with a mirror attached. 相似文献
ABSTRACTEmbryo viability quantification is an important topic for in vitro fertilization researchers. This study suggests Raman spectroscopy as a candidate method to find an objective measure of embryo viability. Raman spectra of 31 spent embryo culture samples (16 nonpregnant, 15 pregnant) from 31 patients were analyzed with band component analysis. The band area ratio of 902 to 943 cm?1 was found to be the most discriminatory. These bands are related to glutamine, glycine, proline, aspartic acid, and valine. According to the pregnancy outcome the sensitivity and specificity of Raman analysis were found to be 93% and 77%, respectively. 相似文献
Journal of Fluorescence - A facile and green strategy was carried out for the preparation of fluorescent carbon nanoparticles (CNp) using non-toxic circassian seeds as carbon precursor (CNp, named... 相似文献
Physics of Particles and Nuclei Letters - Plastic scintillators are widely used in detecting nuclear radiation due to their low construction cost, the ability to be produced in nearly any shape and... 相似文献
One of the main concerns during the COVID-19 pandemic was the protection of healthcare workers against the novel coronavirus. The critical role and vulnerability of healthcare workers during the COVID-19 pandemic leads us to derive a mathematical model to express the spread of coronavirus between the healthcare workers. In the first step, the SECIRH model is introduced, and then the mathematical equations are written. The proposed model includes eight state variables, i.e., Susceptible, Exposed, Carrier, Infected, Hospitalized, ICU admitted, Dead, and finally Recovered. In this model, the vaccination, protective equipment, and recruitment policy are considered as preventive actions. The formal confirmed data provided by the Iranian ministry of health is used to simulate the proposed model. The simulation results revealed that the proposed model has a high degree of consistency with the actual COVID-19 daily statistics. In addition, the roles of vaccination, protective equipment, and recruitment policy for the elimination of coronavirus among the healthcare workers are investigated. The results of this research help the policymakers to adopt the best decisions against the spread of coronavirus among healthcare workers.
A series of dihydropyrimidine analogues were prepared via one-pot Biginelli three-component condensation reaction and characterized by NMR, FT-IR, MS spectra, and element analysis. Subsequently, they were screened for in vitro anticancer effect. These analogues revealed good cytotoxic activity against three human cancer cell lines including MCF-7, HepG-2, and A549. Among these analogues, compounds 4d and 4h were the most potent against three cell lines. Cell viability assays indicated 4a and 4c had lower cytotoxicity. In vitro cytotoxicity study on all synthesized compounds demonstrated that introduction of electron withdrawing substituents on C4 position of phenyl ring of dihydropyrimidine contributed to the antiproliferative potency. Moreover, in silico molecular docking results stipulated a sign of good correlation between experimental activity and calculated binding affinity. It proved 4d and 4h as the strongest compounds. Binding modes of analogues proposed the involvement of hydrophobic interactions and hydrogen bonds with Eg5 active site. Structure activity relationship studies indicated that incorporating electron withdrawing substituents on C4 position of phenyl ring of dihydropyrimidine are important for this biological activity. 相似文献
Nonlinear Dynamics - This paper proposes a fractional-order reset element whose architecture allows for the suppression of nonlinear effects for a range of frequencies. Suppressing the nonlinear... 相似文献
Journal of Thermal Analysis and Calorimetry - In the current work, after generating experimental data points for different volume fraction of nanoparticles ( $$\phi$$ ) and different temperatures,... 相似文献
To purify the mammalian cell membrane porphyrin binding proteins (PBP), an original affinity chromatographic technique is proposed. The method is based on the application of an agarose attached fullerene-porphyrin ligand connected to a polysaccharide gel matrix through the epoxy-cyclohexyl residue interface. A selective PBP-stationary phase coupling has been managed in a single column chromatographic run leading to a complete purification of the 17.6 kDa monomer protein from the rat myocardium mitochondria membranes. A synchronous pH and ionic strength linear gradients were used to separate this protein with a high specific affinity to the porphyrin K related structures from all non-specific sorption retained membrane proteins. 相似文献