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The alkylation of phenol with methanol was studied in vapor phase over 5 wt% cerium supported on HZSM-5 catalyst prepared by three different methods, such as impregnation, ball mixing and solid-state ion-exchange. The catalytic activities are tested in a fixed-bed reactor, and the physicochemical properties of the catalyst are characterized with X-ray powder diffraction, scanning electron microscope, nitrogen physical sorption, Fourier Transform Infrared Spectrometer, Infrared spectra of pyridine adsorption, X-ray photoelectron spectroscopy and temperature-programmed desorption of ammonia. It was found that the dispersion form of cerium was greatly affected by the preparation method, and difference in acidity affects catalytic performance in the alkylation reaction of phenol and methanol. Ball milling method generated greater amount of strong Brønsted acidic sites and lower specific surface area than other catalysts, which led to higher carbon deposition rate and lower catalyst activity. The catalyst prepared by impregnation method yields higher Lewis acid concentration (2.09 μmol/g) and more chemisorbed oxygen due to the increased Ce3+ concentration in the lattice, resulted in an improved o-cresol selectivity of 48%. Furthermore, the catalyst prepared by solid-phase ion-exchange method produces a catalyst with appropriate B/L ratio of 60.6 and large specific surface area of 389.0 m2/g, which yields the highest phenol conversion of 23%. [ABSTRACT FROM AUTHOR]

Two processes of high‐salinity water (≥34.7 psu; HSW) intrusion were recorded by an Argo float in the northeastern South China Sea (SCS) during fall‐winter of 2015/2016. Combined with the satellite altimetry and reanalysis data, the influence of related eddy pairs on HSW transport was investigated. The results show that apart from the Kuroshio‐originated anticyclonic eddy (AE), the localized cyclonic eddy (CE), and the westward jet between the eddy pair all contributed to the HSW transport. In the first process, the effect of eddy trapping accounted for 74% of the HSW transport, while the associated jet accounted for the residual 26%. The contribution of the southern CE was stronger than that of the northern AE. In the second process, the Kuroshio‐originated AE and its southern jet dominated the HSW transport. The westward jet conveyed abundant HSW to the interior SCS before the eddy pair propagated westward, accounting for 52% of HSW transport, while AE accounted for 43% and CE for 5%. Energy analysis showed that barotropic and baroclinic instabilities were important for the generation and growth of the AE in both processes, and CE in the first process was produced by baroclinic instability and wind stress work, while CE in the second process was predominantly triggered by barotropic instability. The development of eddy pairs combined with the SCS interior circulation jointly affected the HSW transport. This study identified the important contributions from two eddy pairs and discussed the effect of interior circulation‐Kuroshio interaction on HSW intrusion in the northern SCS. Plain Language Summary: In this study, we report a special case in which two successive anticyclonic eddies were shed from the Kuroshio into the South China Sea (SCS) during fall‐winter of 2015/2016. We focus on the high‐salinity water (HSW) intrusion induced by the eddy pair that includes the Kuroshio‐originated anticyclonic eddy and the localized cyclonic eddy. The eddies and their associated jet contribute to the transport of HSW from the western Pacific to the northern SCS. The relative contributions of eddy trapping and jet transport were related to the development of the eddy pair and the interior circulation in the SCS. Key Points: Two processes of eddy pair intrusion were revealed in the northeastern South China Sea during fall‐winter of 2015/2016The northern anticyclonic and southern cyclonic eddies, together with their associated jet, affected the high‐salinity water transportThe interior circulation and the development of eddy pairs jointly affected the relative contributions of eddy trapping and jet transport [ABSTRACT FROM AUTHOR]

The South China Sea (SCS) is a highly semi-enclosed marginal sea located in the East Asian monsoon region. This paper proposes interesting aspects of the unique feature of the SCS waves in response to tropical cyclone's passage when large-scale winter monsoon winds prevail. We use the wave model WaveWatch III to study the wave characteristics of typhoon Durian (2006) passing over the middle of SCS in early December 2006, and state the new understanding acquired in the aspects of the tropical cyclone generated waves in the SCS during winter monsoon surge. In light of this, the role of the large-scale NE monsoon winds on winter typhoon wave field characteristics in the SCS are highlighted by conducting sensitivity experiments with and without the NE monsoon winds. The NE monsoon winds weakly affect the SWH field near the typhoon track and strongly away from the track, especially in the deep water area of the northern SCS where the NE monsoon winds produce high waves. Comparisons between the two experiments show the effect of the NE monsoon winds on the directional wave spectra in the SCS, suggesting that the monsoon-generated swells do not decay and remain throughout the typhoon period. [ABSTRACT FROM AUTHOR]

Pulmonary vascular remodeling is the most important pathological characteristic of pulmonary arterial hypertension (PAH). No effective treatment for PAH is currently available because the mechanism underlying vascular remodeling is not completely clear. CD248, also known as endosialin, is a transmembrane protein that is highly expressed in pericytes and fibroblasts. Here, we evaluated the role of CD248 in pulmonary vascular remodeling and the processes of PAH pathogenesis. Activation of CD248 in pulmonary artery smooth muscle cells (PASMCs) was found to be proportional to the severity of PAH. CD248 contributed to platelet‐derived growth factor‐BB (PDGF‐BB)‐induced PASMC proliferation and migration along with the shift to more synthetic phenotypes. In contrast, treatment with Cd248 siRNA or the anti‐CD248 therapeutic antibody (ontuxizumab) significantly inhibited the PDGF signaling pathway, obstructed NF‐κB p65‐mediated transcription of Nox4, and decreased reactive oxygen species production induced by PDGF‐BB in PAMSCs. In addition, knockdown of CD248 alleviated pulmonary vascular remodeling in rat PAH models. This study provides novel insights into the dysfunction of PASMCs leading to pulmonary vascular remodeling, and provides evidence for anti‐remodeling treatment for PAH via the immediate targeting of CD248. [ABSTRACT FROM AUTHOR]

Fresh onions (Allium cepa L.) emit volatile organic compounds (VOCs) naturally in very low concentrations. The aim of the present study was to determine the emission rate of low-boiling VOCs from healthy and naturally infected onion bulbs at 4, 15, and 25 °C and to evaluate the applicability of the VOC method to monitor quality changes during 12 weeks of storage of two cultivars ('Hystand' and 'Hoza') of yellow onions. VOCs were extracted from the headspace of bulbs by solid phase micro-extraction (SPME) up to 5 times during storage and analyzed by gas chromatography–mass spectrometry (GC–MS). A total of twenty-nine compounds were measured and twenty-seven of these were identified while thirteen were reported for the first time from yellow onion bulbs. Acetone (0.10–18.0 nmol kg−1 day−1), dimethyl disulfide (0.12–18.9 nmol kg−1 day−1) and hexanal (0.05–4.40 nmol kg−1 day−1) were among the most abundant volatiles emitted from healthy bulbs. The concentration of these compounds as well as the total volatiles decreased with time in storage. However, microbial infection resulted in higher emission of propene, carbon disulfide, isoprene, pentane, 2-methylfuran, 3-methylfuran, 1-propenethiol, hexane, and methyl propyl sulfide, indicating that VOC emission may be used as an indicator to monitor natural senescence and decay of stored onion bulbs. [ABSTRACT FROM AUTHOR]

A long shelf life of onions (Allium cepa L.) is of high importance in the onion industry. Onions are dried and stored in large wooden boxes that are difficult to access. Monitoring temperature and relative humidity during these processes is challenging. Moreover, quality may change in storage without being noticed. Therefore, there is a need to find alternative methods for monitoring and controlling the drying and storage processes of onions and to identify early changes in quality during storage. The potential use of online measurements of temperature and relative humidity (RH) in the vicinity of onions was evaluated during drying and long-term storage of six onion batches (four cultivars and three selections of one of the cultivars) in commercial storage. The batches varied in bulb weight, dry matter content, firmness and disease incidence. The dry matter content and firmness decreased during storage, while the respiration rate and incidences of individual and total disease increased. Two of the batches had low storability with high disease incidences and high average temperatures and variations in the RH. The results showed that tracking the temperature and RH in the vicinity of the onions is a promising tool for improving the drying and storage processes in commercial storage and for identifying onion batches with reduced storability early in storage. [ABSTRACT FROM AUTHOR]

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Based on coastal tide level, satellite altimetry, and sea surface temperature (SST) data of offshore areas of China’s coast and the equatorial Pacific Ocean, the regional characteristics of the effects of the El Niño-Southern Oscillation (ENSO) on the sea level in the China Sea were investigated. Singular value decomposition results show a significant teleconnection between the sea level in the China Sea and the SST of the tropical Pacific Ocean; the correlation coefficient decreases from south to north. Data from tide gauges along China’s coast show that the seasonal sea-level variations are significantly correlated with the ENSO. In addition, China’s coast was divided into three regions based on distinctive regional characteristics. Results obtained show that the annual amplitude of sea level was low during El Niño developing years, and especially so during the El Niño year. The ENSO intensity determined the response intensity of the annual amplitude of the sea level. The response region (amplitude) was relatively large for strong ENSO intensities. Significant oscillation periods at a timescale of 4-7 years existed in the sea level of the three regions. The largest amplitude of oscillation was 1.5 cm, which was the fluctuation with the 7-year period in the South China Sea. The largest amplitude of oscillation in the East China Sea was about 1.3 cm. The amplitude of oscillation with the 6-year period in the Bohai Sea and Yellow Sea was the smallest (less than 1 cm). [ABSTRACT FROM AUTHOR]

As a natural agent for chemotherapy, deguelin remarkably suppresses proliferation in numerous solid cancers. Nevertheless, the molecular mechanisms of its suppression are still insufficient. In our research, it was revealed that deguelin induced cell death of lung cancer cells (LCCs) by triggering expression of PUMA. Deguelin triggered PUMA induction independently of p53 via suppression of PI3K/AKT pathway, therefore stimulating Foxo3a to bind with PUMA promoter and stimulate its transcription. Subsequent to activation, PUMA motivated Bax as well as the intrinsic mitochondrial cell death pathway. Removal of PUMA from LCC cells led to deguelin resistance, suggesting deguelin-induced cell death was modulated by PUMA. Furthermore, we demonstrated that deguelin enhanced the chemotherapeutic sensitivity of doxorubicin in vitro and in vivo, which were associated with potentiated PUMA induction. Taken together, these results establish a critical role of PUMA in mediating the anticancer effects of deguelin in lung cancer cells and provide the rationale for clinical evaluation. [ABSTRACT FROM AUTHOR]

Obesity and cigarette smoke are major cardiovascular (CV) risk factors and, when coexisting in the same individuals, have additive/synergistic effects upon CVD. We studied the mechanisms involved in nicotine enhancement of CVD in Sprague Dawley rats with diet–induced obesity. The rats were fed either a high fat (HFD) or normal rat chow diet with or without nicotine (100 mg/L in drinking water) for 20 weeks. HFD rats developed central obesity, increased systolic blood pressure (SBP), aortic superoxide (O2-) production, and impaired endothelial nitric oxide synthase (eNOS) and endothelium-dependent relaxation to acetylcholine (EDR). Nicotine further increased SBP, O2- and impaired eNOS and EDR in obese rats. In the peritoneal macrophages from obese rats, tumor necrosis factor (TNF) α, interleukin 1β and CD36 were increased, and were further increased in nicotine-treated obese rats. Using PCR array we found that 3 of 84 target proinflammatory genes were increased by 2–4 fold in the aorta of obese rats, 11 of the target genes were further increased in nicotine-treated obese rats. HUVECs, incubated with conditioned medium from the peritoneal macrophages of nicotine treated-obese rats, exhibited reduced eNOS and increased NADPH oxidase subunits gp91phox and p22phox expression. Those effects were partially prevented by adding anti-TNFα antibody to the conditioned medium. Our results suggest that nicotine aggravates the CV effects of diet–induced obesity including the oxidative stress, vascular inflammation and endothelial dysfunction. The underlying mechanisms may involve in targeting endothelium by enhancement of macrophage-derived TNFα. [ABSTRACT FROM AUTHOR]

Puerarin is an isoflavonoid isolated from the Chinese herb, Kudzu roots (also known as Gegen), which has been widely used for the treatment of hypertensive diseases and diabetic mellitus in traditional Chinese medicine. Dahl salt-sensitive (DS) rat is a genetic model of salt-sensitive hypertension with cardiovascular injury and vascular insulin resistance. Here, we investigated whether puerarin improved vascular insulin resistance and attenuated cardiac and aortic remodeling in salt-sensitive hypertension. DS rats were given a normal (NS) or high salt diet (HS) for five weeks. An additional group of DS rats was pretreated with puerarin and NS for 10 days, then switched to HS plus puerarin for five weeks. HS for five weeks increased systolic blood pressure (SBP), cardiac hypertrophy and fibrosis, and aortic hypertrophy with increased the expression of phosphor-ERK1/2 in the aorta and heart; puerarin attenuated cardiac and aortic hypertrophy, cardiac fibrosis and phosphor-ERK1/2 with a mild reduction in SBP. Hypertensive rats also manifested impairment of acetylcholine- and insulin-mediated vasorelaxation and insulin-mediated Akt and eNOS phosphorylation associated with the activation of NFB/TNF/JNK pathway. Puerarin improved acetylcholine- and insulin-mediated vasorelaxation and insulin-stimulated Akt/NO signaling with the inhibition of the NFB inflammatory pathway. Our results demonstrated that in salt-sensitive hypertension, puerarin improved vascular insulin action with cardiovascular beneficial effects. Our results found that the underlying mechanisms may involve its inhibition of NFB/JNK and ERK1/2 pathway. These results suggest that puerarin could be used as a new antihypertensive agent to expand our armamentarium for the prevention and treatment of end-organ damage in individuals with hypertension and metabolic diseases. [ABSTRACT FROM AUTHOR]

Puerarin, a major isoflavonoid compound from Chinese herb Kudzu roots, has been widely used for the treatment of hypertensive and cardiovascular diseases in China. Here, we investigated puerarin’s beneficial effects on the cardiovascular system in angiotensin (Ang) II-induced hypertensive rats. Sprague–Dawley rats were treated with Ang II for 5 days or with puerarin for 10 days followed by Ang II and puerarin for 5 days. Endothelium-dependent relaxation (EDR) to acetylcholine was determined using an organ chamber bath. Ang II increased the systolic blood pressure (SBP: 178 ± 5 mmHg vs. 112 ± 3 mmHg in control,p< 0.05), aortic (30%,p< 0.05), and left ventricular (LV) weight (23%); puerarin reduced SBP (160 ± 2 mmHg,p< 0.05), aortic, and left ventricular weight in Ang II-infused rats. Puerarin also reduced aortic medial thickness and myocardial cell surface area in Ang II-infused rats. Compared with control rats, Ang II infused rats exhibited an impaired EDR with reduction in the protein expression of phosphor-eNOS at Ser 1177 and an increase in the expression of gp91phox (85%), p22phox (113%), transforming growth factor β1 (145%) and vascular cell adhesion molecule 1 (82%). Puerarin improved EDR and reversed the changes in Ang II-induced protein expression of above molecules. Our results demonstrate that in Ang II-induced hypertensive rats, puerarin protects against endothelial dysfunction and end organ damage with a mild reduction in SBP, and that the cardiovascular beneficial effects of puerarin may be in part attributed to its anti-oxidant and upregulation of phosphor-eNOS. [ABSTRACT FROM AUTHOR]

Wang, A. M.; Wang, H. J.; Bi, N. S., and Wu, X., 2016. Sediment transport and dispersal pattern from the Bohai Sea to the Yellow Sea. Suspended sediment flux, dispersal patterns and its possible mechanisms in the Bohai Sea were investigated based on the observational data in May and November, 2012, data retrieved from MODIS imageries and the ocean current data from HYCOM. The sediment dispersal pattern and the annual net sediment flux presented evident seasonal variability. During wintertime, the prevailing strong northerly winds and the related high wave heights resuspended the sediment along the coast of the Huanghe Delta that was transported into the Laizhou Bay along its western coast and exported to the Bohai Strait through the eastern Laizhou Bay as enhanced by the coastal current. The wintertime contributed approximately 4.84 Mt of suspended sediment flux to the Yellow Sea, as higher than the flux in summertime by one order. In summertime, the less energetic environment together with the stratified water column was unfavorable to the sediment export to the Yellow Sea. As a result, the sediment delivered by the Huanghe to the sea in summertime mostly accumulated within the subaqueous delta, which acted as a primary source of sediment export to the Yellow Sea in wintertime. [ABSTRACT FROM AUTHOR]

A novel and simple process for the preparative extraction, separation, and purification of high-purity (–)-borneol and xanthoxylin, synchronously, from the leaves ofBlumea balsamifera(L.) DC was developed. Simultaneous distillation and extraction, silica gel column chromatography, and recrystallization were applied to the preparation. Two objective compounds with the purity of 98% were obtained, and the losses were minimal during the whole procedure. It is the first time that the preparation of high-purity (–)-borneol and xanthoxylin at the same time were achieved. [ABSTRACT FROM AUTHOR]