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1.
Middle East respiratory syndrome coronavirus (MERS-CoV) causes high fever, cough, acute respiratory tract infection and multiorgan dysfunction that may eventually lead to the death of the infected individuals. MERS-CoV is thought to be transmitted to humans through dromedary camels. The occurrence of the virus was first reported in the Middle East and it subsequently spread to several parts of the world. Since 2012, about 1368 infections, including ~487 deaths, have been reported worldwide. Notably, the recent human-to-human ‘superspreading'' of MERS-CoV in hospitals in South Korea has raised a major global health concern. The fatality rate in MERS-CoV infection is four times higher compared with that of the closely related severe acute respiratory syndrome coronavirus infection. Currently, no drug has been clinically approved to control MERS-CoV infection. In this study, we highlight the potential drug targets that can be used to develop anti-MERS-CoV therapeutics.  相似文献   
2.
Convenient and straightforward tetrabutylammonium bromide (TBAB), benzyltrienthylammonium chloride (BTEAC), and cetyltrimethylammonium bromide (CTAB) catalyzed synthesis of 1,4-dihydropyridines (1,4-DHPs) in water was established for the first time. The catalytic potential of phase-transfer catalysts (PTCs) in three different concentrations was envisioned. Aryl aldehydes and hetero aryl aldehydes afforded good yields of 1,4-DHPs in TBAB and BTEAC reactions. In particular, furfuraldehyde and thienyl-2-carbaldehyde produced excellent yields. Isolation of the products through nonchromatographic methods, good to excellent yields, and benign reaction conditions are the major advantages of this protocol.  相似文献   
3.
Glycolic acid was polymerized under vacuum in the presence and absence of nano sized clay.The added clay catalyzed the condensation polymerization which can be confirmed by recording FTIR spectroscopy and intrinsic viscosity (Ⅳ)values.The relative intensity of C=O/CH is increased while increasing the amount of clay.DSC showed the appearance of multiple endotherms of poly(glycolic acid).TGA showed the percentage weight residue remain above 750℃for polymer-nano composite system was 21% and hence proved the...  相似文献   
4.
Journal of Applied Spectroscopy - Amitriptyline hydrochloride (AMH) is a first-generation tricyclic antidepressant drug. Higher doses of AMH may lead to undesirable clinical conditions such as...  相似文献   
5.
Elevated ground-level ozone is hazardous to people’s health and destructive to the environment. This research develops a novel data-integrated simulation to forecast ground-level ozone (SIMGO) concentration based on a real data set collected from seven monitoring sites in the Dallas-Fort Worth area between January 1, 2005 and December 31, 2007. Tree-based models and kernel density estimation (KDE) were utilized to extract important knowledge from the data for building the simulation. Classification and Regression Trees (CART), data mining tools for prediction and classification, were used to develop two tree structures in order to forecast ground-level ozone based on factors such as solar radiation and outdoor temperature. Kernel density estimation is used to estimate continuous distributions for the ground-level ozone concentration for seven days in advance. One week forecasts obtained from SIMGO for different months of a year is presented.  相似文献   
6.
Phase-transfer-catalyzed, highly versatile, and high-yielding protocol for the synthesis of 2,4,5-triaryl-1H-imidazoles was developed through response surface methodology (RSM). The effects of different solvents, reaction paths, and phase-transfer catalysts (PTCs) in different concentrations were envisioned. Three independent variables (catalyst, catalyst loading, and solvent volume) identified by one-factor-at-a-time (OFAT) study were screened through full factorial design at two levels. The analysis of variance results suggested the significance of catalyst PEG400 and solvent glacial acetic acid at 5 h reaction. The optimum reaction conditions suggested by the RSM were the use of PEG400 (10.61 mol%) and glacial acetic acid (10.71 mL) for 5 h cycloocondensation. The experimental yield of 4,5-diphenyl-2-nitrophenyl-1H-imidazole (97%) was in agreement with predicted yield (97.5%).  相似文献   
7.
We report the synthesis and characterization of polyphenylated fluorene derivatives and a ring cyclized product containing cyclopenta[def]triphenylene core. Polybromination on fluorene was achieved either by solid state reaction with bromine or utilizing Br2/KBrO3 in AcOH/H2SO4 mixture. The bromofluorenes were converted to the corresponding polyphenylated fluorenes by Suzuki coupling protocol. A hexabromofluorene underwent a multifold Suzuki coupling followed by C–H activation to produce a cyclopenta[def]triphenylene derivative. Fluorene ring showed a severe distortion from planarity beyond tetra-substitution which manifested in the optical properties.  相似文献   
8.
We have developed two bacterial one-hybrid systems for interrogating and selecting zinc finger-DNA interactions. Our systems utilize two plasmids: a zinc finger-plasmid containing the gene for the zinc finger fused to a fragment of the alpha subunit of RNA polymerase and a reporter plasmid where the zinc finger-binding site is located upstream of a reporter gene-either the gene encoding the green fluorescent protein (GFP) or chloramphenicol acetyltransferase (CAT). Binding of the zinc finger domain to the target binding site results in a 10-fold increase in chloramphenicol resistance with the CAT reporter and an 8- to 22-fold increase in total cell fluorescence with the GFP reporter. The CAT reporter allows for sequence specific zinc fingers to be isolated in a single selection step whereas the GFP reporter enables quantitative evaluation of libraries using flow cytometry and theoretically allows for both negative and positive selection. Both systems have been used to select for zinc fingers that have affinity for the motif 5'-GGGGCAGAA-3' from a library of approximately 2 x 10(5) variants. The systems have been engineered to report on zinc finger-DNA binding with dissociation constants less than about 1 microM in order to be most applicable for evaluating binding specificity in an in vivo setting.  相似文献   
9.
An approach for the secure transmission of encrypted messages using chaos and noise is presented in this paper. The method is based on the synchronization of certain types of chaotic oscillators in response to a common noise input. This allows two distant oscillators to generate identical output which can be used as a key for encryption and decryption of a message signal. The noiselike synchronizing input-which contains no message information-is communicated to identical oscillators in the transmitter and the receiver over a public channel. The encrypted message is also sent over a public channel, while the key is never transmitted at all. The chaotic nature of the oscillators which generate the key and the randomness of the signal driving the process combine to make the recovery of the key by an eavesdropper extremely difficult. We evaluate system performance with respect to security and robustness and show that a robust and secure system can be obtained. (c) 1998 American Institute of Physics.  相似文献   
10.
Glutathione (GSH) undergoes facile electron transfer with vanadium(V)-substituted Keggin-type heteropolyoxometalates, [ \textPV\textV \textW 1 1 \textO 4 0 ] 4 - [ {\text{PV}}^{\text{V}} {\text{W}}_{ 1 1} {\text{O}}_{ 4 0} ]^{{ 4 { - }}} (HPA1) and [ \textPV\textV \textV\textV \textW 1 0 \textO 4 0 ] 5 - [ {\text{PV}}^{\text{V}} {\text{V}}^{\text{V}} {\text{W}}_{ 1 0} {\text{O}}_{ 4 0} ]^{{ 5 { - }}} (HPA2). The kinetics of these reactions have been investigated in phthalate buffers spectrophotometrically at 25 °C in aqueous medium. One mole of HPA1 consumes one mole of GSH and the product is the one-electron reduced heteropoly blue, [ \textPV\textIV \textW 1 1 \textO 40 ] 5- [ {\text{PV}}^{\text{IV}} {\text{W}}_{ 1 1} {\text{O}}_{ 40} ]^{ 5- } . But in the GSH-HPA2 reaction, one mole of HPA2 consumes two moles of GSH and gives the two-electron reduced heteropoly blue [ \textPV\textIV \textV\textIV \textW 10 \textO 40 ] 7- [ {\text{PV}}^{\text{IV}} {\text{V}}^{\text{IV}} {\text{W}}_{ 10} {\text{O}}_{ 40} ]^{ 7- } . Both reactions show overall third-order kinetics. At constant pH, the order with respect to both [HPA] species is one and order with respect to [GSH] is two. At constant [GSH], the rate shows inverse dependence on [H+], suggesting participation of the deprotonated thiol group of GSH in the reaction. A suitable mechanism has been proposed and a rate law for the title reaction is derived. The antimicrobial activities of HPA1, HPA2 and [ \textPV\textV \textV\textV \textV\textV \textW 9 \textO 4 0 ] 6 - [ {\text{PV}}^{\text{V}} {\text{V}}^{\text{V}} {\text{V}}^{\text{V}} {\text{W}}_{ 9} {\text{O}}_{ 4 0} ]^{{ 6 { - }}} (HPA3) against MRSA were tested in vitro in combination with vancomycin and penicillin G. The HPAs sensitize MRSA towards penicillin G.  相似文献   
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