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A series of rasagiline-clorgyline hybrids was designed, synthesized and investigated in vitro for their inhibition of monoamine oxidase and amyloid-β aggregation. Most of compounds were found to be selective and highly potent hMAO-B inhibitors showing IC 50 values in the nanomolar, and exhibited a moderate inhibition of amyloid-β aggregation. 7-((5-(methyl(prop-2-yn-1-yl)amino) pentyl)oxy)chroman-4-one (6j) was the most interesting compound identified in this research, endowed with higher hMAO-B potency (IC 50 = 4 nM) and selectivity (SI > 25000) compared to the reference selective inhibitor rasagiline (IC 50 = 141 nM, SI > 355), and exhibited good inhibitory activity against Aβ 1-42 aggregation (40.78%, 25 μM). Kinetic and molecular modeling studies revealed that 6j was a competitive reversible inhibitor for hMAO-B. Moreover, compound 6j displayed low toxicity and good neuroprotective effects in SH-SY5Y cell assay, and could penetrate the blood-brain barrier according to the parallel artificial membrane permeability assay. Pharmacokinetics assay revealed that compound 6j possessed good pharmacokinetic profiles after intravenous and oral administrations. Overall, these results highlighted that compound 6j was an effective and promising multitarget agent against Alzheimer's disease. Image 1 • Twenty rasagiline-clorgyline hybrids were designed and synthesized. • All compounds were highly selective and potent h MAO-B inhibitors. • 6j exhibited low nanomolar inhibition for MAO-B and good inhibition for Aβ 1-42 aggregation. • 6j showed neuroprotective effects and could penetrate the BBB. • 6j had good pharmacokinetic characteristics after intravenous and oral administrations. [ABSTRACT FROM AUTHOR]

Thermal conductivity is required for developing high-power microwave technology. Diamond has the highest thermal conductivity in nature. In this study, a diamond film was synthesized by microwave plasma chemical deposition, and then long and short conductive graphite fibers were introduced to the diamond films by laser ablation. The permittivity of the samples in the K-band was measured using the transmission/reflection method. The permittivity of diamond films with short graphite fibers increased. The increase in real part of permittivity can be attributed to electron polarization, and the increase in the imaginary part can be ascribed to both polarization and electrical conductivity. The diamond films with long graphite fibers exhibited a highly pronounced anisotropy for microwave. The calculation of microwave absorption shows that reflection loss values exceeding −10 dB can be obtained in the frequency range of 21.3–23.5 GHz when the graphite fiber length is 0.7 mm and the sample thickness is 2.5 mm. Therefore, diamond films can be developed into a microwave attenuation material with extremely high thermal conductivity. [ABSTRACT FROM AUTHOR]

It has been known that boron-doped diamond (BDD) is an ideal electrode material since it has the advantages of wide potential window, low background current, good corrosion resistance and strong electrochemical oxidation capability. In this paper, we will show that by preparing BDD as a composite, a new electrode material may be produced. To preparing such a composite, BDD and titanium (Ti) powders have been selected as the electrochemically active material and the matrix, respectively, and spark plasma sintering has been used as the fabrication procedure. Electrochemical tests proved that after an appropriate passivation, surface of the Ti matrix would acquire an insulating property, and the Ti-BDD composite as a whole would possess characteristics of a BDD material, including wide potential window, high oxygen evolution potential and low background current. Degradation tests conducted with glucose solution showed that the composite possessed also good electrochemical oxidation performance and chemical oxygen demand removal capability. Very importantly, accelerated life test proved that the composite as an anode material may have much longer lifetime than that of a BDD coating electrode produced by conventional chemical vapor deposition processes. All these preliminary experimental results suggested that Ti-BDD composite as a new anode material may have bright prospect in electrochemical applications. Unlabelled Image • Boron-doped diamond composite was prepared as a new anode material. • The composite has the same good electrochemical properties as the boron doped diamond coatings. • The composite may have longer lifetime than that of the boron doped diamond coatings. [ABSTRACT FROM AUTHOR]

• Twenty-eight chromanone-dithiocarbamate hybrids were designed and synthesized. • 6c showed potential inhibition for both AChE and Aβ aggregation. • 6c exhibited no acute toxicity in mice and could penetrate the BBB. • 6c could significantly reverse scopolamine-induced memory deficit in vivo. By connecting chromanone with dithiocarbamate moieties through flexible linkers, a series of hybrids as novel multifunctional AChE inhibitors have been designed and synthesized. Most of these compounds displayed strong and excellently selective inhibition to eeAChE as well as potent inhibition to self- and AChE-induced Aβ aggregation. Among them, compound 6c showed the best activity to inhibit eeAChE (IC 50 = 0.10 μM) and AChE-induced Aβ aggregation (33.02% at 100 μM), and could effectively inhibit self-induced Aβ aggregation (38.25% at 25 μM). Kinetic analysis and docking study indicated that compound 6c could target both the CAS and PAS, suggesting that it was a dual binding site inhibitor for AChE. Besides, it exhibited good ability to penetrate the BBB and low neurotoxicity in SH-SY5Y cells. More importantly, compound 6c was well tolerated in mice (2500 mg/kg, po) and could attenuate the memory impairment in a scopolamine-induced mouse model. Overall, these results highlight 6c as a promising multifunctional agent for treating AD and also demonstrate that the dithiocarbamate is a valid scaffold for design of multifunctional AChE inhibitors. [ABSTRACT FROM AUTHOR]