Atmospheric reactivity and oxidation capacity during summer at a suburban site between Beijing and Tianjin

Hydroxyl (OH) radicals, nitrate (NO3) radicals and ozone (O-3) play central roles in the troposphere because they control the lifetimes of many trace gases that result from anthropogenic and biogenic origins. To estimate the air chemistry, the atmospheric reactivity and oxidation capacity were comprehensively analyzed based on a parameterization method at a suburban site in Xianghe in the North China Plain from 6 July 2018 to 6 August 2018. The total OH, NO3 and O-3 reactivities at the site varied from 9.2 to 69.6, 0.7 to 27.5 and 3.3 x 10(-4 )to 1.8 x 10(-2) s(-1) with campaign-averaged values of 27.5 +/- 9.7, 2.2 +/- 2.6 and 1.2 +/- 1.7 x 10(-3) s(-1) (+/- standard deviation), respectively. NOx (NO + NO2) was by far the main contributor to the reactivities of the three oxidants, with average values of 43 %-99 %. Alkenes dominated the OH, NO3 and O-3 reactivities towards total nonmethane volatile organic compounds (NMVOCs), accounting for 42.9 %, 77.8 % and 94.0 %, respectively. The total OH, NO3 and O-3 reactivi- ties displayed similar diurnal variations with the lowest values during the afternoon but the highest values during rush hours, and the diurnal profile of NOx appears to be the major driver for the diurnal profiles of the reactivities of the three oxidants. A box model (a model to Simulate the concentrations of Organic vapors, Sulfuric Acid and Aerosols; SOSAA) derived from a column chemical transport model was used to simulate OH and NO3 concentrations during the observation period. The calculated atmospheric oxidation capacity (AOC) reached 4.5 x 10(8) molecules cm(-3) s(-1), with a campaign-averaged value of 7.8 x 10 7 molecules cm(-3) s(-1) dominated by OH (7.7 x 10(7) molecules cm(-3) s(-1), 98.2 %), 0 3 (1.2 x 10(6) molecules cm(-3) s(-1), 1.5 %) and NO3 (1.8 x 10(5) molecules cm(-3) s(-1), 0.3 %). Overall, the integration of OH, NO3 and O-3 reactivities analysis could provide useful insights for NMVOC pollution control in the North China Plain. We suggest that further studies, especially direct observations of OH and NO3 radical concentrations and their reactivities, are required to better understand trace gas reactivity and AOC.Peer reviewe

Eye Movement Study on Attention Bias to Body Height Stimuli in Height Dissatisfied Males

The present study investigated attention bias in response to height-related words among young men in China. 47 [26 high height dissatisfied (HHD) and 21 low height dissatisfied (LHD)] men performed a dot-probe task. Eye movement (EM) recordings showed that compared to LHD men, HHD men had an avoidance bias in response to height-related words, which was revealed by less frequent first fixations on both tall-related and short-related words, and showed significantly shorter first fixations on short-related words. There was no other significant difference in EM indices (i.e., first fixation latency and gaze duration) between two groups. In addition, HHD participants were significantly slower than LHD participants when responding to probes preceded by short-related words, while there was no difference when probes were preceded by tall-related or neutral words. In sum, the present results indicate that HHD men selectively avoid cues related to short height

Toxicity and degradation of 2,4,6-trinitrotoluene in transgenic Arabidopsis expressing Citrobacter freundii nitroreductase

AbstractThe degradation of organic pollutants in plants involves uptake and diffusion through the roots, trunk or leaves, transformation, accumulation and/or volatilization of soil- and aqueous-phase contaminants. 2,4,6-trinitrotoluene (TNT), the most widely used explosive, is toxic to a number of photosynthetic organisms, poses hazards to human health and pollutes the environment because it is recalcitrant to degradation. In this study, we investigated the nitroreductase gene from Citrobacter freundii in transgenic Arabidopsis thaliana plants. Transgenic plants showed a promising ability to tolerate, take up and detoxify TNT. Our results suggest that transgenic plants show higher potential for removing and transformation of TNT. The expression of nitroreductase in Arabidopsis could be useful for phytoremediation and could be explored for the effective cleanup of TNT-contaminated sites

Total Flavonoids of Drynariae Rhizoma Prevent Bone Loss Induced by Hindlimb Unloading in Rats

Drynariae Rhizoma is a kidney-tonifying herb that has a long history in clinical practice for the treatment of bone fractures and joint diseases in China. Flavonoids are considered to be its major active ingredients and are reported to ease bone loss in ovariectomized rats. However, the beneficial effects of the total flavonoids of Drynariae Rhizoma on osteoporosis caused by microgravity or mechanical inactivity remain unknown. This study assessed the effects of total Drynariae Rhizoma flavonoids (DRTF, Qihuang, Beijing, China, national medicine permit No. Z20030007, number of production: 04080081, content of DRTF ≥80%) against bone loss induced by simulated microgravity. A hindlimb unloading tail-suspended rat model was established to determine the effect of DRTF on bone mineral density (BMD), biomechanical strength and trabecular bone microarchitecture. Twenty-eight male Sprague–Dawley rats were divided into four groups: the baseline, control, hindlimb unloading with vehicle (HLU), and hindlimb unloading treated with DRTF (HLU–DRTF, 75 mg/kg/day) groups. Oral DRTF was administered for 4 weeks. The underlying mechanisms of the DRTF actions on disuse-induced osteoporosis are discussed. The results showed that DRTF treatment significantly increased the BMD and mechanical strength of tail-suspended rats. Enhanced bone turnover markers with HLU treatment were attenuated by DRTF administration. Deterioration of trabecular bone induced by HLU was prevented through elevated bone volume/tissue volume (BV/TV), trabecular number (Tb. N), trabecular thickness (Tb. Th) and decreased trabecular separation (Tb. Sp). The present study provides the first evidence that DRTF prevents bone loss induced by HLU treatment, indicating its potential application in the treatment of disuse-induced osteoporosis

Vitamin E Can Ameliorate Oxidative Damage of Ovine Hepatocytes In Vitro by Regulating Genes Expression Associated with Apoptosis and Pyroptosis, but Not Ferroptosis

(1) Background: the current research was conducted to investigate the potential non-antioxidant roles of vitamin E in the protection of hepatocysts from oxidative damage. (2) Methods: primary sheep hepatocytes were cultured and exposed to 200, 400, 600, or 800 μmol/L hydrogen peroxide, while their viability was assessed using a CCK-8 kit. Then, cells were treated with 400 μmol/L hydrogen peroxide following a pretreatment with 50, 100, 200, 400, and 800 μmol/L vitamin E and their intracellular ROS levels were determined by means of the DCF-DA assay. RNA-seq, verified by qRT-PCR, was conducted thereafter: non-treated control (C1); cells treated with 400 μmol/L hydrogen peroxide (C2); and C2 plus a pretreatment with 100 μmol/L vitamin E (T1). (3) Results: the 200–800 μmol/L hydrogen peroxide caused significant cell death, while 50, 100, and 200 μmol/L vitamin E pretreatment significantly improved the survival rate of hepatocytes. ROS content in the cells pretreated with vitamin E was significantly lower than that in the control group and hydrogen-peroxide-treated group, especially in those pretreated with 100 μmol/L vitamin E. The differentially expressed genes (DEGs) concerning cell death involved in apoptosis (RIPK1, TLR7, CASP8, and CASP8AP2), pyroptosis (NLRP3, IL-1β, and IRAK2), and ferroptosis (TFRC and PTGS2). The abundances of IL-1β, IRAK2, NLRP3, CASP8, CASP8AP2, RIPK1, and TLR7 were significantly increased in the C1 group and decreased in T1 group, while TFRC and PTGS2 were increased in T1 group. (4) Conclusions: oxidative stress induced by hydrogen peroxide caused cellular damage and death in sheep hepatocytes. Pretreatment with vitamin E effectively reduced intracellular ROS levels and protected the hepatocytes from cell death by regulating gene expression associated with apoptosis (RIPK1, TLR7, CASP8, and CASP8AP2) and pyroptosis (NLRP3, IL-1β, and IRAK2), but not ferroptosis (TFRC and PTGS2)

Promising Subjective and Objective Benefits of Modified Mindfulness-Based Stress Reduction Training for Chinese Adults with Chronic Pain: A Pilot Randomized Control Study

Abstract Introduction Mindfulness-based stress reduction (MBSR) has demonstrated its effectiveness in reducing pain-related stress in adults with chronic pain. However, the implementation of MBSR needs modifications across cultures. This pilot study reports the findings of a randomized controlled trial that investigated the effects of a culturally adaptive MBSR program on self-report and neuroimaging outcomes for chronic pain adults in China. Methods Sixty-seven participants were randomly assigned to the treatment group (n = 40) or the treatment-as-usual group (n = 27) group at a ratio of 1.5:1. Participants completed self-report measures of pain severity, pain interference, depression, perceived stress, pain catastrophizing, mindfulness, and resilience at baseline assessment (T1), post-treatment (T2), and 3-month follow-up (T3) assessments. Functional magnetic resonance imaging (fMRI) scanning was also performed at T1 and T3 assessments. Results For the intention-to-treat sample, the results of the mixed-effect model indicated that Group × Time interaction was significant for pain catastrophizing only (F (2, 130) = 3.51, p = 0.033). Compared with the control group, those in the MBSR group reported greater reductions in pain catastrophizing at T2 (d = − 0.60), though this effect was not maintained at T3 (d = − 0.05). Additionally, the results of completer analyses found significant Group × Time interactions for pain interference (F (2, 88) = 4.40, p = 0.015) and perceived stress (F (2, 88) = 3.13, p = 0.048), but not for other measures. Finally, both groups exhibited decreased regional homogeneity (ReHo) in the frontal lobe, while increased ReHo in the cerebellum anterior lobe was unique to the MBSR group. Conclusions The present findings suggest that the minor modified MBSR program improves certain pain-related outcomes for Chinese adults with chronic pain. Future studies with larger samples of Chinese chronic pain patients are needed to detect the small-to-moderate benefit of MBSR on fMRI and/or other objective methods

Paclobutrazol Ameliorates Low-Light-Induced Damage by Improving Photosynthesis, Antioxidant Defense System, and Regulating Hormone Levels in Tall Fescue

Paclobutrazol (PBZ) is a plant-growth regulator (PGR) in the triazole family that enhances plant tolerance to environmental stresses. Low-light (LL) intensity is a critical factor adversely affecting the growth of tall fescue (Festuca arundinacea Schreb.). Therefore, in this study, tall fescue seedlings were treated with PBZ under control and LL conditions to investigate the effects of PBZ on enhancing LL stress resistance by regulating the growth, photosynthesis, oxidative defense, and hormone levels. Our results reveal that LL stress reduced the total biomass, chlorophyll (Chl) content, photosynthetic capacity, and photochemical efficiency of photosystem II (PSII) but increased the membrane lipid peroxidation level and reactive oxygen species (ROS) generation. However, the application of PBZ increased the photosynthetic pigment contents, net photosynthetic rate (Pn), maximum quantum yield of PSII photochemistry (Fv/Fm), ribulose-1,5-bisphosphate carboxylase (RuBisCO) activity, and starch content. In addition, PBZ treatment activated the antioxidant enzyme activities, antioxidants contents, ascorbate acid-glutathione (AsA-GSH) cycle, and related gene expression, lessening the ROS burst (H2O2 and O2∙−). However, the gibberellic acid (GA) anabolism was remarkably decreased by PBZ treatment under LL stress, downregulating the transcript levels of kaurene oxidase (KO), kaurenoic acid oxidase (KAO), and GA 20-oxidases (GA20ox). At the same time, PBZ treatment up-regulated 9-cis-epoxycarotenoid dioxygenase (NCED) gene expression, significantly increasing the endogenous abscisic acid (ABA) concentration under LL stress. Thus, our study revealed that PBZ improves the antioxidation and photosynthetic capacity, meanwhile increasing the ABA concentration and decreasing GA concentration, which ultimately enhances the LL stress tolerance in tall fescue

High-Surface-Area Porous Carbon Flakes Derived from Boat-Fruited Sterculia Seeds for High-Energy-Density Aqueous Symmetric Supercapacitors

A new kind of N-doped porous carbon flake with a super high surface area of 3243.92 m² g^–1 was derived from a common biomass waste (boat-fruited sterculia seeds) by a facile low-cost pyrolysis and activation method. This particular biomass has a natural netlike structure consisting of interconnected polysaccharide chains rich in hydrophilic groups. We used the spongelike biomass gel as carbon precursor directly without a drying process and added some NaCl as the structure template, and were surprised to find that it is crucial for high surface area and the formation of two-dimensional materials. It is noted that the obtained materials possess a high specific capacitance (411.5 F g^–1 at 1 A g^–1) and excellent cycling stability in aqueous electrolytes. Moreover, the assembled symmetric cell with has a wide voltage range of 2.0 V in 1 M Na₂SO₄ aqueous electrolyte, delivering a high energy density of 22.4 W h kg^–1 at 500 W kg^–1. Therefore, the outstanding electrochemical performance of the developed materials makes them promising candidates for high-performance supercapacitors