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CHALCONE, MONOAMINE oxidase inhibitors, MONOAMINE oxidase, DOCKING of molecules, and NEUROLOGICAL disorders

The inhibition of monoamine oxidase B (MAO-B) could be an effective approach for the treatment of various neurological disorders. In this study, a series of 1, 4-benzodioxan-substituted chalcone derivatives were designed, synthesised and evaluated for their inhibitory activity against human MAO-B (hMAO-B). The majority of these compounds showed inhibitory activity and high selectivity. The most potent compound, (E)-1-(3-bromo-4-fluorophenyl)-3-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)prop-2-en-1-one (22), exhibited an IC50 of 0.026 µM with a selectivity index greater than 1538. Kinetics and reversibility studies confirmed that the representative active compounds acted as competitive and reversible inhibitors of hMAO-B. The enzyme-inhibitor interactions were investigated by molecular docking studies and the rationale was provided. As these potent hMAO-B inhibitors exhibited low neurotoxicity and possessed promising drug-like properties, we believe that these active compounds could be further investigated as potential drug candidates for future in vivo studies. [ABSTRACT FROM AUTHOR]

DOCKING of molecules, SULFONAMIDES, MONOAMINE oxidase, and ENZYMES

Many studies have been conducted on the selective inhibition of human monoamine oxidase B (hMAO-B) enzyme using benzylamine-sulphonamide derivatives. Using various chemical modifications on BB-4h, which was reported previously by our team and showed a significant level of MAO-B inhibition, novel benzylamine-sulphonamide derivatives were designed, synthesised, and their MAO inhibition potentials were evaluated. Among the tested derivatives, compounds 4i and 4t achieved IC50 values of 0.041 ± 0.001 µM and 0.065 ± 0.002 µM, respectively. The mechanism of hMAO-B inhibition by compounds 4i and 4t was studied using Lineweaver–Burk plot. The nature of inhibition was also determined to be non-competitive. Cytotoxicity tests were conducted and compounds 4i and 4t were found to be non-toxic. Molecular docking studies were also carried out for compound 4i, which was found as the most potent agent, within hMAO-B catalytic site. [ABSTRACT FROM AUTHOR]

Job security, Employment policy, Violence in the workplace, Work environment, Employment, Public opinion, and Communist parties

This article examines how China's Communist Party (CCP) sought to justify its policies fostering inequality at the urban factory floor in the early years after Mao's death through publications in the People's Daily. The article focuses on three issues that emerged frequently in the newspaper: the increased prevalence of incentive wages, the abolishment of life-time employment for workers and the evolving discourse related to worker influence at their workplace. The article shows that the People's Daily did not simply seek to persuade the public that the reforms were compatible with socialism, the newspaper also took great care to showcase which kinds of behaviours and emotions would be appropriate for the new working subject. The CCP's dedication to reforming the population through the press makes the People's Daily an excellent source for tracking norm intransigence on the part of the population. Based on the observation that the CCP sought to legitimate policies ending employment security many years before such policies were adopted, the article also suggests that public opinion had a direct influence on the timing of the early reforms. [ABSTRACT FROM AUTHOR]

THIN films, MAGNETIC anisotropy, MAGNETIC films, PULSED laser deposition, FERROMAGNETIC resonance, and MAGNETOSTRICTION

In order to acquire a soft magnetic film with low conductivity and large magnetic anisotropy, the strain-modulated magnetic anisotropy is studied in epitaxial MgFe2O4 (MFO) films. The MFO films with thicknesses of 25, 48, 75, and 110 nm are grown on the MgAl2O4 (MAO) (100) substrate using a pulsed laser deposition technique. Due to the large lattice-mismatch (3.34%) between MFO and MAO substrates, the interface exhibits a large tetragonal compressive strain. The results of field-dependent magnetization suggest the soft magnetic nature of all the measured MFO films. The analysis of angular dependent ferromagnetic resonance reveals the large uniaxial magnetic anisotropy energy (Ku) of −1.62 × 106 erg/cm3 in the highly strained 25 nm film, and Ku decreases with the increasing thickness due to strain relaxation. The observed large magnetic anisotropy in these highly strained MFO thin films is larger than most of the soft ferrite thin films, which arise due to tetragonal distortion and inverse magnetostriction. The epitaxial MFO thin films with enhanced magnetic anisotropy could be one of the potential candidates for spin filters. [ABSTRACT FROM AUTHOR]

COMPOSITE coating, ALLOYS, MICROSTRUCTURE, CORROSION & anti-corrosives, and CORROSION resistance

For micro-arc oxidation (MAO) coating on aluminium alloys, the corrosion medium can permeate through the microvoids and cracks in it to decrease its corrosion resistance. In this study, a method of two-steps hydrothermal synthesis has been developed to prepare a composite coating by the synthesis of zeolite film on MAO-coated Al alloy substrate. The zeolite crystals are well intergrown into a continuous film and the micro defects in the MAO coating are sealed. This kind of composite coating can provide excellent long-term corrosion protection to Al alloy substrate. The effect of the first-step hydrothermal synthesis on the microstructure of the MAO coating and zeolite film has been studied. [ABSTRACT FROM AUTHOR]

TRANSCRANIAL magnetic stimulation, MONOAMINE oxidase, TREATMENT effectiveness, MENTAL depression, and ELECTROMAGNETIC fields

Repetitive transcranial magnetic stimulation (rTMS) is a neuromodulation technique that stimulates cortical regions via time-varying electromagnetic fields; in several countries this technique has been approved as a treatment for major depressive disorder. One empirically established target in antidepressant pharmacotherapy is the flavin-containing monoamine oxidoreductase (MAO). The function of MAO enzymes is based on oxidation processes that may be sensitive towards strong electromagnetic fields. Therefore, we hypothesized that rTMS-induced electromagnetic fields impact the activity of this enzyme. Using crude synaptosomal cell preparations from human SH-SY5Y neuroblastoma cells and rat cortex as well as viable cells, we assessed the effects of rTMS on MAO-A and -B activity in a well-controlled in vitro set up. In short, samples were stimulated at maximal intensity with an equal number of total stimuli at frequencies of 5, 20, and 100 Hz. Sham stimulation was performed in parallel. Treatment at frequencies of 5 and 20 Hz significantly decreased mainly MAO-B activity in all tissue preparations and species, whereas 100 Hz stimulation remained without effect on any MAO activity. Our results support the hypothesis, that rTMS-induced electromagnetic fields affect MAO activity and provide further evidence for intracellular effects possibly contributing to therapeutic effects of this neuromodulatory method. On a cautionary note, however, our findings are solely based on in vitro evidence. [ABSTRACT FROM AUTHOR]

POLYAMINES, MONOAMINE oxidase, STRUCTURE-activity relationships, OXIDASES, ORNITHINE decarboxylase, MOLECULAR structure, and NEURODEGENERATION

The two human monoamine oxidase isoforms (namely MAO A and MAO B) are enzymes involved in the catabolism of monoamines, including neurotransmitters, and for this reason are well‐known and attractive pharmacological targets in neuropsychiatric and neurodegenerative diseases, for which novel pharmacological approaches are necessary. Benextramine is a tetraamine disulfide mainly known as irreversible α‐adrenergic antagonist, but able to hit additional targets involved in neurodegeneration. As the molecular structures of monoamine oxidases contain nine cysteine residues, the aim of this study was to evaluate benextramine and eleven structurally related polyamine disulfides as potential MAO inhibitors. Most of the compounds were found to induce irreversible inactivation of MAOs with inactivation potency depending on both the polyamine structure and the enzyme isoform. The more effective compounds generally showed preference for MAO B. Structure‐activity relationships studies revealed the key role played by the disulfide core of these molecules in the inactivation mechanism. Docking experiments pointed to Cys323, in MAO A, and Cys172, in MAO B, as target of this type of inhibitors thus suggesting that their covalent binding inside the MAO active site sterically impedes the entrance of substrate towards the FAD cofactor. The effectiveness of benextramine in inactivating MAOs was demonstrated in SH‐SY5Y neuroblastoma cell line. These results demonstrated for the first time that benextramine and its derivatives can inactivate human MAOs exploiting a mechanism different from that of the classical MAO inhibitors and could be a starting point for the development of pharmacological tools in neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

MONOAMINE oxidase, GROUP 15 elements, STRUCTURE-activity relationships, MOLECULAR models, and ANTIOXIDANTS

A new series of 4-(3-nitrophenyl)thiazol-2-ylhydrazone derivatives were designed, synthesised, and evaluated to assess their inhibitory effect on the human monoamine oxidase (hMAO) A and B isoforms. Different (un)substituted (hetero)aromatic substituents were linked to N1 of the hydrazone in order to establish robust structure–activity relationships. The results of the biological testing demonstrated that the presence of the hydrazothiazole nucleus bearing at C4 a phenyl ring functionalised at the meta position with a nitro group represents an important pharmacophoric feature to obtain selective and reversible human MAO-B inhibition for the treatment of neurodegenerative disorders. In addition, the most potent and selective MAO-B inhibitors were evaluated in silico as potential cholinesterase (AChE/BuChE) inhibitors and in vitro for antioxidant activities. The results obtained from molecular modelling studies provided insight into the multiple interactions and structural requirements for the reported MAO inhibitory properties. [ABSTRACT FROM AUTHOR]

INTEGRINS, MESENCHYMAL stem cells, HYDROXYAPATITE coating, TITANIUM, ADHESION, SURFACE coatings, and BONE marrow

A variety of surface modification methods are applied to modify titanium implants to improve their biological activity. Micro-arc oxidation (MAO) can relatively simply and efficiently produce porous coatings with high bioactivity and bond strength on titanium surfaces. However, there is no conclusion about the effect of coatings with different pore sizes produced by MAO on bone marrow mesenchymal stem cells (BMSCs). To study the effect of different pore sizes on BMSCs, rat BMSCs were applied to detect the effect of different pore sizes prepared by MAO on cell adhesion and osteogenic differentiation. Three groups of coatings with different pore sizes were successfully prepared, and the pore size was within the range of 3–10 µm. Importantly, the expression of adhesion-related protein integrin β1 and osteogenic-related proteins OSX and ALP increased along with the increase in pore size. This study showed that the porous coating prepared by MAO promotes BMSCs adhesion and osteogenic differentiation. It reveals that the pore size is in the range of 3–10 µm and the larger pores are more beneficial for BMSCs adhesion and osteogenic differentiation. This study is instructive for optimizing the design of biomedical implant surfaces. [ABSTRACT FROM AUTHOR]

PEARSON correlation (Statistics) and VECTOR autoregression model

This paper investigates a class of statistics based on Pearson's correlation coefficient for testing the mutual independence of a random vector in high dimensions. Two existing statistics, proposed by Schott (2005) and Mao (2014) respectively, are special cases of the class. A generic testing theory for the class of statistics is developed, which clarifies under what conditions the class of statistics can be employed for the testing purpose. By virtue of the theory, three new tests are introduced, and related statistical properties are discussed. To examine our theoretical findings and check the performance of the new tests, simulation studies are applied. The simulation results justify the theoretical findings and show that the newly introduced tests perform well, as long as both the dimension and the sample size of the data are moderately large. [ABSTRACT FROM AUTHOR]

MONOAMINE oxidase, ABDOMINAL adipose tissue, WHITE adipose tissue, ADIPOSE tissues, MESENTERIC artery, OXIDATIVE stress, and HEART metabolism disorders

Obesity is an important preventable risk factor for morbidity and mortality from cardiometabolic disease. Oxidative stress (including in visceral adipose tissue) and chronic low-grade inflammation are the major underlying pathomechanisms. Monoamine oxidase (MAO) has recently emerged as an important source of cardiovascular oxidative stress. The present study was conducted to evaluate the role of MAO as contributor to reactive oxygen species (ROS) production in white adipose tissue and vessels harvested from patients undergoing elective abdominal surgery. To this aim, visceral adipose tissue and mesenteric artery branches were isolated from obese patients with chronic inflammation and used for organ bath, ROS production, quantitative real-time PCR, and immunohistology studies. The human visceral adipose tissue and mesenteric artery branches contain mainly the MAO-A isoform, as shown by the quantitative real-time PCR and immunohistology experiments. A significant upregulation of MAO-A, the impairment in vascular reactivity, and increase in ROS production were found in obese vs. non-obese patients. Incubation of the adipose tissue samples and vascular rings with the MAO-A inhibitor (clorgyline, 30 min) improved vascular reactivity and decreased ROS generation. In conclusion, MAO-A is the predominant isoform in human abdominal adipose and vascular tissues, is overexpressed in the setting of inflammation, and contributes to the endothelial dysfunction. [ABSTRACT FROM AUTHOR]

DISTRIBUTION management, MARITIME management, ECONOMIC models, TRANSPORTATION management, HARBOR management, and HARBORS

Mao, Y. and Gan, S., 2019. Economic evaluation model of freight distribution management in maritime port. In: Guido-Aldana, P.A. and Mulahasan, S. (eds.), Advances in Water Resources and Exploration. Journal of Coastal Research, Special Issue No. 93, pp. 1059–1065. Coconut Creek (Florida), ISSN 0749-0208. The economic benefit evaluation model of seaborne port cargo distributed transportation management is proposed based on big data's integrated dispatching of resources, and the explanatory variable model and control variable model of the economic benefit evaluation of seaborne port cargo distributed transportation management is analyzed by using quantitative analysis method. The distribution characteristics of economic statistical information and the characteristics of association rules in the management of seaborne port cargo distributed transportation are taken into account. Rough evaluation set and economic statistical information distribution structure model of cargo distributed transportation management are constraint parameters, so fuzzy subspace scheduling model is constructed to design the control model for economic benefit evaluation of cargo distributed transportation management in seaborne ports. Based on the quantitative regression analysis of the intervention factors of the economic statistical participants in the management of goods distributed transportation, the benefit evaluation theory and regression analysis method of the distributed transportation of goods in the seaborne port are used to carry out the management of the distributed transportation of the goods in the seaborne port, and the economic statistical information fusion and clustering algorithm of the distributed transportation management of the goods in the seaborne port are combined to realize the economic benefit evaluation of the distributed transportation management of the goods in the seaborne port. The simulation results show that the economic benefit evaluation of seaborne port cargo distributed transportation management is accurate, and the adaptive evaluation ability and confidence of the economic evaluation quality benefit coefficient of seaborne port cargo distributed transportation management are strong. [ABSTRACT FROM AUTHOR]

FLOOD risk, LAND use, ANALYTIC hierarchy process, GEOGRAPHIC information systems, FLOODS, and WATER supply

Mao, D.; Fu, X.; Wang, J., and Guo, R., 2019. Assessment of flood vulnerability of the Dongting Lake Area in China with regard to land use/cover change. In: Guido-Aldana, P.A. and Mulahasan, S. (eds.), Advances in Water Resources and Exploration. Journal of Coastal Research, Special Issue No. 93, pp. 388–396. Coconut Creek (Florida), ISSN 0749-0208. A flood vulnerability comprehensive evaluation model (FVCEM) was established by interpreting remote sensing (RS) image data for 1987, 1998, and 2008 using Environment for Visualizing Images (ENVI) software and a geographical information system (GIS), as well as analysing historical disaster maps and statistical yearbook data regarding flood disasters in the Dongting Lake Area in China. Using the method of analytic hierarchy process (AHP) etc., the influence of land use/cover change on flood vulnerability was studied. The vulnerability of the local population and economy to flooding was assessed by means of FVCEM. The results showed that the vulnerability parameters of hazard-affected bodies were different for different land use types, which influenced the subsequent flood vulnerability. The flood vulnerability value over the period of 1987-2008 exhibited an increasing trend, with obvious spatial heterogeneity. The hinterland of the Dongting Lake Area was found to be susceptible to flood hazard. The flood risk regionalization and risk management should be carried out urgently by local government according to the temporal and spatial vary characteristics of flood vulnerability, land use model suitable for these characteristics should be constructed timely by residents. [ABSTRACT FROM AUTHOR]

ETHYLENE, CHROMIUM, LIGANDS, POLYMERIZATION, MASS spectrometry, CHROMIUM compounds, and METALLOCENE catalysts

A new series of Cr (III) complexes [Cr{1‐(3‐phenoxypropyl)‐1H‐pyrazole}Cl3]2(Cr1), [Cr{1‐(3‐phenoxypropyl)‐3,5‐dimethyl‐1H‐pyrazole}Cl3]2(Cr2), and [Cr{1‐(3‐phenoxypropyl)‐3‐phenyl‐1H‐pyrazole}Cl3]2(Cr3) have been synthesized and characterized by elemental analysis, high‐resolution mass spectrometry (HRMS) and IR spectroscopy. Upon activation with methylaluminoxane (MAO), chromium precatalysts Cr2 and Cr3 showed moderate activity in ethylene oligomerization [TOF = 17,900–29,200 mol (ethylene)·mol (Cr)−1·h−1 at 80 °C] with Schultz‐Flory distribution of oligomers (K = 0.54–0.66) and production of polymer varying from 2.8 to 6.7 wt.%. On the other hand, under identical oligomerization conditions, Cr1/MAO behaved as a polymerization catalyst generating predominantly polyethylene (63.7 wt%). The amount of 1‐butene is the largest component in the liquid fraction suggesting that these precatalysts operate via a Cossee‐Arlman mechanism. The catalytic activities, selectivity and product distribution are quite sensitive to the R‐group at the 3‐ and 5‐position of the pyrazolyl ring. Based on the electronic and steric effects of R‐ substituents, it is possible to stablish a trend of activity: Cr2(PzMe2) > Cr3(PzPh) > Cr1(Pz). Moreover, the effect of oligomerization parameters (cocatalyst, temperature, [Al]/[Cr] molar ratio, time) on the activity and on the product distribution were examined. [ABSTRACT FROM AUTHOR]

ALUMINUM oxidation, ALUMINUM alloys, DIFFUSION coatings, PROTECTIVE coatings, ANODIC oxidation of metals, and SURFACE coatings

The microarc oxidation (MAO) coating and anodic oxidation coating were prepared on 5083 aluminum alloy. The surface morphology, elemental composition, and electrochemical behavior of the two coatings were analyzed. The results proved that the corrosion resistance of the MAO coating is superior than that of the anodic oxidation coating. The protective ability of the coating deteriorated gradually with the increase in immersion time. The corrosion process is controlled by ion diffusion throughout the coatings. [ABSTRACT FROM AUTHOR]

CALCIUM phosphate, HIERARCHIES, UNIFORM spaces, PHOSPHATE coating, TENSILE tests, OSSEOINTEGRATION, and DRUG carriers

A relationship between the structural-morphological and physical-mechanical properties of macro-porous calcium phosphate (CaP) coatings on the surface of titanium implants is studied. The produced CaP coatings can be used as carriers for target drug delivery in biomedical applications. The regularities of the formation of bulk (thickness of 15–130 μm) and rough (Ra = 1.7–8.5 μm) CaP coatings deposited by the micro-arc oxidation (MAO) method are studied. The coatings have a hierarchical porous structure and a uniform distribution of the structural elements (spheres and pores) over the surface. Correlations between the value of the applied voltage and structural-morphological and physical-mechanical characteristics of the CaP coatings have been established. The value of the coating adhesion strength has been determined with tensile tests. Both cohesive and mixed adhesive-cohesive pull-off of the MAO coating from the substrate have been identified. [ABSTRACT FROM AUTHOR]