Sunshine duration (SD) is adopted widely to study global dimming/brightening. However, long-term simultaneous measurements of SD and closely related impact factors require further analysis to ...elucidate how and why SD has varied during the past decades. In this study, a long-term (1958–2021) SD data series obtained from the Shangdianzi Global Atmosphere Watch (GAW) station in China was analyzed to detect linear trends, climatic jumps, and climatic periods in SD using linear fitting, the Mann–Kendall trend test, and the continuous wavelet transform method. Annual SD exhibited steady dimming (−67.3 h decade
−1
) before 2010, followed by a period of brightening (189.9 h decade
−1
) during 2011–2020. An abrupt jump in annual SD occurred in 1995, and the annual SD anomaly exhibited significant oscillation with ∼3-yr periodicity during 1960–1978. Partial least squares analysis revealed that annual SD anomaly was associated with variations in relative humidity, gale days, cloud cover, and black carbon (BC). Further analysis of the clear-sky daily sunshine percentage (DSP) and simultaneous measurements of aerosol properties, including aerosol optical depth, aerosol extinction coefficient, single scattering albedo (SSA), BC, and total suspended particulates, suggested that variation in DSP was affected primarily by aerosol scattering and absorption. Furthermore, the hourly clear-sky SD at high aerosol loading was approximately 60% and 56% of that at middle and low aerosol loadings, respectively. The pattern of diurnal variation in clear-sky hourly SD, as well as the actual values, can be affected by the fine particulate concentration, aerosol extinction coefficient, and SSA.
Cu
2
O/CuO composite thin films were synthesized by a facile hydrothermal method on Cu foils. Surface morphology, chemical composition, microstructure and wettability were investigated by scanning ...electron microscope, X-ray photoelectron spectroscopy, X-ray diffractometer and water contact angle apparatus. The results indicate that the Sample 2 is composed of many regular Cu
2
O octahedrons, tiny nanovillus and a small amount of spheric particles. The other samples were composed mainly of flower-like microparticles and regular Cu
2
O octahedrons. The content of copper (II) increases firstly and then decreases and the maximal value of content of copper (II) has been observed in the Sample 2. The Sample 2 displayed superhydrophobic property owing to its hierarchical porous micro/nanostructured surface.
Gram-positive organisms have re-emerged as the major hospital pathogens, which make the unmet medical needs for antibacterial therapy even worse. In searching for potent agents against Gram-positive ...pathogens, novel 7-(substituted)-aminomethyl-quinolone-3-carboxylic acids were designed, synthesized, and evaluated for their antibacterial activities in vitro. Many 7-monoarylaminomethyl derivatives exhibited high potency against Gram-positive organisms compared to reference agents: vancomycin and pazufloxacin. Additionally, a few 7-monoalkylaminomethyl derivatives exhibited good activities against both Gram-positive and Gram-negative organisms.
Although several therapeutic agents are available to aid in tobacco smoking cessation, relapse rates continue to be high, warranting the development of alternative pharmacotherapies. Nicotine-evoked ...dopamine release from its presynaptic terminals in the central nervous system leads to reward which maintains continued tobacco use. The ability of indolizidine (−)-235B′ and a sub-library of structurally related analogs to inhibit nicotine-evoked
3Hdopamine release from rat striatal slices was determined in the current study. Indolizidine (−)-235B′ inhibited nicotine-evoked
3Hdopamine release in a concentration-dependent manner (IC
50
=
42
nM, I
max
=
55%). Compound (−)-237D, the double bond-reduced analog, afforded the greatest inhibitory potency (IC
50
=
0.18
nM, I
max
=
76%), and was 233-fold more potent than indolizidine (−)-235B′. The
des-8-methyl aza-analog of indolizidine (−)-235B′, ZZ-272, also inhibited nicotine-evoked
3Hdopamine release (IC
50
=
413
nM, I
max
=
59%). Concomitant exposure to maximally effective concentrations of indolizidine (−)-235B′, ZZ-272 or (−)-237D with a maximally effective concentration of α-conotoxin MII, a selective antagonist for α6β2-containing nicotinic receptors, resulted in inhibition of nicotine-evoked
3Hdopamine release no greater than that produced by each compound alone. The latter results suggest that indolizidine (−)-235B′, (−)-237D, ZZ-272 and α-conotoxin MII inhibit the same α-conotoxin MII-sensitive nicotinic receptor subtypes. Thus, indolizidine (−)-235B′ and its analogs act as antagonists of α6β2-nicotinic receptors and constitute a novel structural scaffold for the discovery of pharmacotherapies for smoking cessation.
Adenocarcinoma is the most common type of lung cancer. Epithelial-mesenchymal transition (EMT) is required for tumor invasion/metastasis and the components that control this process are potential ...therapeutic targets. This study we examined the role of Gli in lung adenocarcinoma and whether its activation regulates metastasis through EMT in lung adenocarcinoma. We found that tumors with high Gli expression had significantly lower E-Cadherin expression in two independent cohorts of patients with lung adenocarcinoma that we studied. In vitro up-regulation of SHh resulted in increased cell migration while small molecule inhibitors of Smo or Gli significantly reduced cell mobility both in a wound healing assay and in a 3D cell invasion assay. Inhibition of Gli in vivo decreased tumor growth and induced an increase in E-Cadherin expression. Our results indicate that Gli may be critical for lung adenocarcinoma metastasis and that a novel Gli inhibitor shows promise as a therapeutic agent by preventing cell migration and invasion in vitro and significantly reducing tumor growth and increasing E-Cadherin expression in vivo.
Increasing interest has been drawn to the studies of magnetic fluids due to their multiple applications from industry to medicine. However, further exploration is still required for the techniques of ...preparing satisfying, convenient and stable magnetic fluids. We explored characteristics of magnetic liquids prepared by employing co-precipitation techniques of hydrochloric acid (HCl) and polyethylene glycol (PEG), and the functions of HCl and PEG in the magnetic liquid. According to the improved technique, after preparing Fe
3O
4 by a co-precipitation method, hydrochloric acid and PEG2000 react with magnetic particles at a certain temperature to generate the anticipated magnetic nanoparticles. The process could be under an air atmosphere rather than a N
2 atmosphere. Compared with traditional techniques, the magnetic nanoparticles prepared by this method have smaller size, better dispersion and stability, with the average hydrodynamic diameter adjustable between 8 and 50
nm. This study revealed that reduction of nanoparticles size is not mainly due to a Cl
− coating over the magnetic nanoparticles, but that HCl reacts with Fe
3O
4 particles after being heated. Meanwhile, PEG can stabilize or coat Fe
3O
4 nanoparticles as a dispersing and stabilizing agent.
Cu sub(2)O/CuO composite thin films were synthesized by a facile hydrothermal method on Cu foils. Surface morphology, chemical composition, microstructure and wettability were investigated by ...scanning electron microscope, X-ray photoelectron spectroscopy, X-ray diffractometer and water contact angle apparatus. The results indicate that the Sample 2 is composed of many regular Cu sub(2)O octahedrons, tiny nanovillus and a small amount of spheric particles. The other samples were composed mainly of flower-like microparticles and regular Cu sub(2)O octahedrons. The content of copper (II) increases firstly and then decreases and the maximal value of content of copper (II) has been observed in the Sample 2. The Sample 2 displayed superhydrophobic property owing to its hierarchical porous micro/nanostructured surface.
ZnO thin films were synthesized via hydrothermal method on silicon substrate at various solution concentrations. The thin films were characterized by X-ray diffraction, field-emission scanning ...electron microscope and UV–Vis spectrophotometer. The results show that the thin films are polycrystalline with wurtzite hexagonal structure. The
T
c
values of (101) surface of the thin film increase from 0.929 to 1.840 at first, and then decrease to 0.779 with increasing solution concentration. The preferential orientation along the (101) crystal surface can be controlled by changing the solution concentration. Solution concentration has a significant effect on surface morphology of the thin films. The optical band gap of the thin films decreases, when the solution concentration of zinc nitrate hexahydrate increases from 0.01 to 0.06 mol/L and then increases when the solution concentration of zinc nitrate hexahydrate further increases to 0.08 mol/L. Photocatalytic activity of the thin films on degradation of methyl orange under UV light irradiation was studied in detail. The ZnO thin film with many cracks prepared from 0.01 mol/L shows the higher photocatalytic activity but the tower-like ZnO thin film prepared from 0.08 mol/L reveals the lower photocatalytic activity. Therefore, the photocatalytic activity of the thin films are mainly relate to surface morphology and crystallographic orientation.
Crystal structure, surface morphology, surface chemical composition and photocurrent response curves of the thin films were investigated by X-ray diffraction, scanning electron microscopy, X-ray ...photoelectron spectroscopy and electrochemical workstation. The results show that the composite thin films are composed of CuO and Cu
2
O phase. The relative content of copper (I) oxide on the composite thin films increases with the increase of solution concentration. Leaf-like CuO particles have been observed on the thin film grown in the 0.5 mol/L solution. Some regular octahedral and truncated octahedral Cu
2
O particles have been observed on the surface of thin films grown in the 0.6 and 0.8 mol/L solution, respectively. The best photocurrent response and the fastest growth and decay have been observed in the thin film grown in 0.6 mol/L solution.
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