This study evaluated the occurrence of 36 PPCPs in urban river water samples collected from Beijing, Changzhou and Shenzhen. Twenty-eight compounds were detected. Compounds found with highest median ...concentrations included: sulfadimethoxine (164 ng/L), sulpiride (77.3 ng/L), atenolol (52.9 ng/L), and indomethacin (50.9 ng/L). Antibiotic was the predominant class detected and contributed about half of the overall PPCPs contamination level. Effluents from wastewater treatment plants (WWTPs) were demonstrated to be the predominant pathways through which PPCPs entering into aquatic environment in all investigated areas. The ratio of persistent PPCPs like sulpiride and carbamazepine was identified to be feasible in tracing their contamination sources in rivers. Concentrations of most detected PPCPs showed significant positive correlations with total nitrogen and total phosphorus. Two groups of representative PPCPs were selected as the chemical indicators for predicting the overall PPCPs contamination, based on the significant correlations between PPCPs.
•PPCPs were detected at high detection frequencies and average concentrations.•Antibiotics contributed about half of the overall PPCPs contamination level.•Wastewater treatment plant effluent was the dominant contributor to PPCPs residue.•Ratio of two persistent compounds was used in tracing contamination sources.•Two groups of representative PPCPs were selected as surrogate of overall PPCPs.
The occurrence, spatial distribution, sources, and surrogate of Pharmaceuticals and personal care products in aquatic environment of three typical cities across China were demonstrated.
•The aspect ratio of manifold microchannel was optimized at fixed mass flux.•The manifold microchannel has the optimal aspect ratio at fixed mass flux.•The optimal aspect ratio was analyzed at ...various working fluids and solid materials.•A criterion formula of optimal aspect ratio was given.
In order to provide a basis for the design and optimization of the aspect ratio of the manifold microchannel, the effect of channel aspect ratio on the heat transfer performance of manifold microchannel heat sinks at fixed mass flow rate is numerically investigated in this present work. The results show that the heat transfer performance of the manifold microchannel heat sink reaches the peaks at one specific channel aspect ratio, which is defined as optimal aspect ratio αo. It is found that the optimal aspect ratio is different at various working fluids and solid materials. The optimal aspect rises with the increase of thermal conductivity of the channel wall and dynamic viscosity of working fluid, or the decrease of specific heat capacity of working fluid and thermal conductivity of working fluid. Further numerical simulations are conducted to quantitatively analyze the influence of each thermophysical parameter on αo. Finally, a criterion formula is given to describe the optimal aspect ratio as a function of Re number, Pr number, and the ratio of thermal conductivity between working fluid and channel wall.
Acetylshikonin has long been known as an anti‐inflammatory and antioxidative reagent. However, the anti‐allergic effect has not been studied. The aim of this study was to evaluate the effect of ...acetylshikonin on allergic rhinitis (AR) in mice. Mice were sensitized by intraperitoneal injection of OVA and aluminum hydroxide and challenged with intranasal instillation of OVA. Acetylshikonin was administered orally after nasal cavities challenge. Severity of allergic rhinitis was assessed according to nasal symptoms; serum OVA‐specific immunoglobulin E (IgE), IgG1, and IgG2a level; and interleukin (IL)‐4, IL‐10, IL‐5, IL‐13, TNF‐α, IL‐12, and interferon (INF)‐γ levels in nasal lavage fluid (NALF). Additionally, the histological change and the release of histamine in serum and nasal lavage fluid were evaluated by acid‐Schiff stain and ELISA. Acetylshikonin attenuated manifestation of nasal symptoms in sensitized mice and inhibited production of Th2‐related OVA‐specific IgE, IgG1, and Th2 cell‐produced IL‐4, IL‐5, IL‐13, and mast cell produced histamine; however, it had no effect on Th1 cell‐produced cytokines, like INF‐γ. In addition, the degree of inflammatory cell infiltration and goblet cell hyperplasia was attenuated by acetylshikonin treatment. Our results suggest that acetylshikonin effectively reduces allergic inflammation in a mouse model of allergic rhinitis by its anti‐allergic and anti‐inflammatory properties.
Systemic resistance is induced by pathogens and confers protection against a broad range of pathogens. Recent studies have indicated that salicylic acid (SA) derivative methyl salicylate (MeSA) ...serves as a long-distance phloem-mobile systemic resistance signal in tobacco, Arabidopsis, and potato. However, other experiments indicate that jasmonic acid (JA) is a critical mobile signal. Here, we present evidence suggesting both MeSA and methyl jasmonate (MeJA) are essential for systemic resistance against Tobacco mosaic virus (TMV), possibly acting as the initiating signals for systemic resistance. Foliar application of JA followed by SA triggered the strongest systemic resistance against TMV. Furthermore, we use a virus-induced gene-silencing-based genetics approach to investigate the function of JA and SA biosynthesis or signaling genes in systemic response against TMV infection. Silencing of SA or JA biosynthetic and signaling genes in Nicotiana benthamiana plants increased susceptibility to TMV. Genetic experiments also proved the irreplaceable roles of MeSA and MeJA in systemic resistance response. Systemic resistance was compromised when SA methyl transferase or JA carboxyl methyltransferase, which are required for MeSA and MeJA formation, respectively, were silenced. Moreover, high-performance liquid chromatography-mass spectrometry analysis indicated that JA and MeJA accumulated in phloem exudates of leaves at early stages and SA and MeSA accumulated at later stages, after TMV infection. Our data also indicated that JA and MeJA could regulate MeSA and SA production. Taken together, our results demonstrate that (Me)JA and (Me)SA are required for systemic resistance response against TMV.
Our skin is an organ with the largest contact area between the human body and the external environment. Skin aging is affected directly by both endogenous factors and exogenous factors (e.g., UV ...exposure). Skin saccharification, a non-enzymatic reaction between proteins, e.g., dermal collagen and naturally occurring reducing sugars, is one of the basic root causes of endogenous skin aging. During the reaction, a series of complicated glycation products produced at different reaction stages and pathways are usually collectively referred to as advanced glycation end products (AGEs). AGEs cause cellular dysfunction through the modification of intracellular molecules and accumulate in tissues with aging. AGEs are also associated with a variety of age-related diseases, such as diabetes, cardiovascular disease, renal failure (uremia), and Alzheimer’s disease. AGEs accumulate in the skin with age and are amplified through exogenous factors, e.g., ultraviolet radiation, resulting in wrinkles, loss of elasticity, dull yellowing, and other skin problems. This article focuses on the damage mechanism of glucose and its glycation products on the skin by summarizing the biochemical characteristics, compositions, as well as processes of the production and elimination of AGEs. One of the important parts of this article would be to summarize the current AGEs inhibitors to gain insight into the anti-glycation mechanism of the skin and the development of promising natural products with anti-glycation effects.
Objective
To assess pelvic floor muscle (PFM) strength and influencing factors among healthy women at different life stages.
Design
Multicentre cross‐sectional study.
Setting
Fourteen hospitals in ...China.
Population
A total of 5040 healthy women allocated to the following groups (with 1680 women per group): premenopausal nulliparous, premenopausal parous and postmenopausal.
Methods
The PFM strength was evaluated by vaginal manometry. Multivariate logistic regression was used to determine the influencing factors for low PFM strength.
Main Outcome Measures
Maximum voluntary contraction pressure (MVCP).
Results
The median MVCP values were 36, 35 and 35 cmH2O in premenopausal nulliparous (aged 19–51 years), premenopausal parous (aged 22–61 years), and postmenopausal (aged 40–86 years) women, respectively. In the premenopausal nulliparous group, physical work (odds ratio, OR 2.05) was the risk factor for low PFM strength, which may be related to the chronic increased abdominal pressure caused by physical work. In the premenopausal parous group, the number of vaginal deliveries (OR 1.28) and diabetes (OR 2.70) were risk factors for low PFM strength, whereas sexual intercourse (<2 times per week vs. none, OR 0.55; ≥2 times per week vs. none, OR 0.56) and PFM exercise (OR 0.50) may have protective effects. In the postmenopausal group, the number of vaginal deliveries (OR 1.32) and family history of pelvic organ prolapse (POP) (OR 1.83) were risk factors for low PFM strength.
Conclusions
Physical work, vaginal delivery, diabetes and a family history of POP are all risk factors for low PFM strength, whereas PFM exercises and sexual life can have a protective effect. The importance of these factors varies at different stages of a woman's life.
Brassinosteroids (BRs) play essential roles in modulating plant growth, development and stress responses. Here, involvement of BRs in plant systemic resistance to virus was studied. Treatment of ...local leaves in Nicotiana benthamiana with BRs induced virus resistance in upper untreated leaves, accompanied by accumulations of H₂O₂ and NO. Scavenging of H₂O₂ or NO in upper leaves blocked BR‐induced systemic virus resistance. BR‐induced systemic H₂O₂ accumulation was blocked by local pharmacological inhibition of NADPH oxidase or silencing of respiratory burst oxidase homolog gene NbRBOHB, but not by systemic NADPH oxidase inhibition or NbRBOHA silencing. Silencing of the nitrite‐dependent nitrate reductase gene NbNR or systemic pharmacological inhibition of NR compromised BR‐triggered systemic NO accumulation, while local inhibition of NR, silencing of NbNOA1 and inhibition of NOS had little effect. Moreover, we provide evidence that BR‐activated H₂O₂ is required for NO synthesis. Pharmacological scavenging or genetic inhibiting of H₂O₂ generation blocked BR‐induced systemic NO production, but BR‐induced H₂O₂ production was not sensitive to NO scavengers or silencing of NbNR. Systemically applied sodium nitroprusside rescued BR‐induced systemic virus defense in NbRBOHB‐silenced plants, but H₂O₂ did not reverse the effect of NbNR silencing on BR‐induced systemic virus resistance. Finally, we demonstrate that the receptor kinase BRI1(BR insensitive 1) is an upstream component in BR‐mediated systemic defense signaling, as silencing of NbBRI1 compromised the BR‐induced H₂O₂ and NO production associated with systemic virus resistance. Together, our pharmacological and genetic data suggest the existence of a signaling pathway leading to BR‐mediated systemic virus resistance that involves local Respiratory Burst Oxidase Homolog B (RBOHB)‐dependent H₂O₂ production and subsequent systemic NR‐dependent NO generation.
SUMMARY True morels (Morchella spp., Morchellaceae, Ascomycota) are widely regarded as a highly prized delicacy and are of great economic and scientific value. Recently, the rapid development of ...cultivation technology and expansion of areas for artificial morel cultivation have propelled morel research into a hot topic. Many studies have been conducted in various aspects of morel biology, but despite this, cultivation sites still frequently report failure to fruit or only low production of fruiting bodies. Key problems include the gap between cultivation practices and basic knowledge of morel biology. In this review, in an effort to highlight the mating systems, evolution, and life cycle of morels, we summarize the current state of knowledge of morel sexual reproduction, the structure and evolution of mating-type genes, the sexual process itself, and the influence of mating-type genes on the asexual stages and conidium production. Understanding of these processes is critical for improving technology for the cultivation of morels and for scaling up their commercial production. Morel species may well be good candidates as model species for improving sexual development research in ascomycetes in the future.
Pseudomonas aeruginosa secretes multiple proteases that are implicated in its pathogenesis, and most of them are regulated by quorum sensing (QS). In this study, we found that the activities of three ...major extracellular proteases, protease IV (PIV), elastase A (LasA), and elastase B (LasB), are reduced considerably when expressed in a QS mutant (MW1). PIV and LasA expressed in MW1 exhibited little activity, even when purified, and their activities were inhibited by noncleavage or binding of their propeptides. LasB was activated by a QS-dependent factor, indicating that, unlike what has been proposed previously, LasB is not autoactivated. When LasB was relieved from inhibition, it activated PIV, which then sequentially processed pro-LasA to mature LasA. When activated, LasB was not inhibited by exogenous addition of its propeptide, but LasA and PIV were inhibited by their propeptides, even after prior activation. These differences may be explained by the fact that LasB can degrade its own propeptide but PIV and LasA cannot. We also found that, although PIV is the preferred LasA-activating factor, LasB can also partially activate LasA. Overall, LasB, PIV, and LasA were activated postsecretionally in a cascading manner in which the initial activation of LasB was controlled tightly by QS at the protein level in addition to the well-known transcriptional control of these proteases by QS. Interestingly, human elastase also activated LasA, indicating that the activation cascade is triggered by host factors during infection. In summary, a QS-induced proteolytic cascade activates secreted proteases from P. aeruginosa.
A speed trajectory profile indicating the authorized train speed at each position can be used to guide the driver or the automatic train operation (ATO) system to operate the train more efficiently, ...which is the most important part of the Chinese Train Control System (CTCS) and will decide the safety and efficiency of train operation. The efforts produced by the train to follow the speed trajectory will directly affect the evaluation of train operation. This paper studies the optimization approach for the speed trajectory of high-speed train in a single section. First, we take the energy consumption as the measure of satisfaction of the railway company, and the trip time is being regarded as the passenger satisfaction criterion; then, we present optimal speed trajectory searching strategies under different track characteristics by dividing the section into some subsections according to different speed limitations. After that, we develop a multiobjective optimization model for the speed trajectory, which is subject to the constraints such as safety requirement, track profiles, passenger comfort, and the dynamic performance. For obtaining the Pareto frontier of train speed trajectory, which has equal satisfaction degree on all the objects, a hybrid evolutionary algorithm is designed and applied to solve the model based on the differential evolution and simulating annealing algorithms. By showing some numerical results of simulations, the efficiency of the proposed model and solution methodology is illustrated.
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