Organophosphate flame retardants (OPFRs) can rapidly biotransform into two types of metabolites in biota: (1) organophosphate diesters (DAPs) and (2) hydroxylated OPFRs (HO-OPFRs). Therefore, the ...levels of parent OPFRs alone are not sufficient to indicate OPFR pollution in biological organisms. This study analyzed 12 OPFR metabolites, including 6 DAPs and 6 HO-OPFRs, in a typical freshwater food chain consisted of crucian carp, catfish, mud carp, snakehead, and oriental river prawn. The total concentrations of OPFR metabolites were comparable to those of parent OPFRs, and ranged from 0.65 to 17 ng/g ww. Bis(2-butoxyethyl) 3′-hydroxy-2-butoxyethyl phosphate (14%–77%), di-n-butyl phosphate (DNBP) (6.7%–24%), bis(1-chloro-2-propyl) phosphate (BCIPP) (0.7%–35%), and 1-hydroxy-2-propyl bis(1-chloro-2-propyl) phosphate (BCIPHIPP) (6.0%–24%) were the major OPFR metabolites. Various aquatic species exhibited significant differences in their OPFR metabolite/parent ratios (MPR) (p < 0.05), indicating varying biotransformation potentials of different organisms for various OPFRs. The growth-independent accumulation of tri-n-butyl phosphate (TNBP), tris(chloro-2-propyl) phosphate (TCIPP), triphenyl phosphate, and 2-ethylhexyl diphenyl phosphate in mud carps could be explained by their biotransformation potential. A significant negative correlation was found between the concentration of bis(2-butoxyethyl) phosphate and δ15N values (p < 0.05), with a calculated trophic magnification factor (TMF) of 0.66. Significant positive correlations were observed between BCIPP and TCIPP (R2 = 0.25, p < 0.05), as well as between DNBP and TNBP (R2 = 0.30, p < 0.01), implying that these two DAPs could be used as biomarkers to quantitatively assess TCIPP and TNBP contamination in wild aquatic organisms.
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•DAPs and HO-OPFRs had high detection frequencies and comparable levels to parent OPFRs.•Biotransformation affected the species- and growth-dependent accumulation of OPFRs.•BBOEP underwent trophic dilution in the aquatic food chain.•DAPs and HO-OPFRs can be used as biomarkers for OPFR monitoring.
To examine the environmental pollution associated with e-waste recycling activities, the concentrations of organohologenated pollutants (OHPs), i.e., short- and medium-chain chlorinated paraffins ...(SCCPs and MCCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and several other halogenated flame retardants (OHFRs), were investigated in surface particulates from the workshop floors of four major e-waste recycling sites (Taizhou, Guiyu, Dali and Qingyuan) in China. The mean levels of SCCPs, MCCPs, PCBs, PBDEs and OHFRs in surface particulates ranged from 30,000–61,000, 170,000–890,000, 2700–27,000, 52,000–240,000, and 62,000–140,000ng/g dry weight (dw), respectively. OHFRs, including decabromodiphenyl ethane, dechlorane plus, 1,2-bis(2,4,6-tribromophenoxy)ethane, tetrabromobisphenol A, hexabromocyclododecanes, polybrominated biphenyls, hexabromobenzene, pentabromotoluene, and pentabromoethylbenzene, were frequently (>50% detection frequency) detected in surface particulates with mean concentration ranges of 39,000–63,000, 310–2700, 98–16,000, 21,000–56,000, 55–5700, 1700–27,000, 42–1600, 3.2–220, and 5.8–12ng/g dw, respectively. The composition of OHPs varied depend on the e-waste items processing in different regions. Guiyu and Dali were typical sites contaminated by halogenated flame retardants (HFRs) and CPs, respectively, while Qingyuan, and Taizhou were representative PCB-polluted regions. The evidence produced by this preliminary study indicated that electronic devices and plastics may account for the high content of HFRs and the metal products are likely the major source of CPs in these e-waste sites.
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•Report of characterizing the types and possible sources of OHPs in e-waste sites•Guiyu was a typical site contaminated by HFRs, while Dali was dominated by CPs.•Qingyuan and Taizhou were representative PCB-polluted regions.•Electronic devices and plastics may account for the high content of HFRs.•Metal products are likely the major source of CPs.
The energy conversion performance of thermophotovoltaic (TPV) systems can be improved when the vacuum gap between the emitter and the TPV cell is at the near-field owing to the photon tunneling of ...evanescent waves. Among them, the back-gapped-reflector TPV systems have gained interest as a method of improving their conversion efficiency by optimizing the spectral absorption of TPV cells. In this work, we introduce an alternative concept for the back-gapped-reflector TPV systems, namely the medium-bridge near-field TPV system, by building a medium bridge between the metal reflector and the TPV cell using SU8 nanofilm. The SU8 medium-bridge achieves a noticeable improvement in output performance by increasing the spectral absorption of the InAs cell and reducing parasitic absorption losses of the Au substrate. The results indicate that, as a consequence of the improved effect of the medium-bridge, the output power density and efficiency of this system exceed those of the conventional TPV system (which lacks a medium-bridge) by 26.4% and 36.5%, respectively. Moreover, we systematically analyze the modulation of medium-bridge thicknesses and cell thickness on output performance and clarify how both affect energy losses of this near-field TPV system. Our work offers a strategy to improve the energy conversion performance of the near-field TPV system, opening new opportunities for developing near-field energy conversion.
Myocardial infarction (MI) causes excessive damage to the myocardium, including the epicardium. However, whether pluripotent stem cell-derived epicardial cells (EPs) can be a therapeutic approach for ...infarcted hearts remains unclear. Here, the authors report that intramyocardial injection of human embryonic stem cell-derived EPs (hEPs) at the acute phase of MI ameliorates functional worsening and scar formation in mouse hearts, concomitantly with enhanced cardiomyocyte survival, angiogenesis, and lymphangiogenesis. Mechanistically, hEPs suppress MI-induced infiltration and cytokine-release of inflammatory cells and promote reparative macrophage polarization. These effects are blocked by a type I interferon (IFN-I) receptor agonist RO8191. Moreover, intelectin 1 (ITLN1), abundantly secreted by hEPs, interacts with IFN-β and mimics the effects of hEP-conditioned medium in suppression of IFN-β-stimulated responses in macrophages and promotion of reparative macrophage polarization, whereas ITLN1 downregulation in hEPs cancels beneficial effects of hEPs in anti-inflammation, IFN-I response inhibition, and cardiac repair. Further, similar beneficial effects of hEPs are observed in a clinically relevant porcine model of reperfused MI, with no increases in the risk of hepatic, renal, and cardiac toxicity. Collectively, this study reveals hEPs as an inflammatory modulator in promoting infarct healing via a paracrine mechanism and provides a new therapeutic approach for infarcted hearts.
A new compound named koninginin W (1) and four known polyketides (2–5) were isolated from endophytic fungus Trichoderma koningiopsis YIM PH30002 of Panax notoginseng. The structures of 1 ‐ 5, ...including absolute configuration of 1, were elucidated on the detailed analysis of the HR‐ESI‐MS, 1D and 2D NMR, and X‐ray crystallographic data. Koninginin W (1) presented weak antibacterial activity against Escherichia coli, Bacillus subtilis and Salmonella typhimurium.
Tai Chi exercise has been shown to improve cancer-related fatigue (CRF) and autonomic nervous system (ANS) balance in some cancer patients or survivors; however, such effects are yet to be verified ...in nasopharyngeal carcinoma (NPC) patients undergoing chemoradiotherapy.
To explore the effects of Tai Chi exercise on CRF in NPC patients undergoing chemoradiotherapy and then to evaluate ANS information indicated by heart rate variability parameters and their association with CRF.
A randomized controlled trial of Tai Chi exercise was conducted from January 2014 to August 2015. Participants in the Tai Chi group practiced Tai Chi a one-hour session, five sessions/week during chemoradiotherapy. Participants in the control group received usual care. The primary end points were scores of the multidimensional fatigue symptom inventory–short form (MFSI-SF). Secondary end points were heart rate variability parameters, including normalized low-frequency (nLF) power, normalized high-frequency (nHF) power, and the nLF/nHF ratio, and their association with CRF.
One hundred fourteen patients were recruited in this study, and 83 patients completed the trial. The Tai Chi group and the control group had comparable baseline characteristics. After chemoradiotherapy, the Tai Chi group exhibited lower MFSI-SF total score and three negative subscale (general, physical, and emotional fatigue) scores and higher vigor score compared with the control group (P < 0.01 for all). The nLF/nHF ratio was significantly lower in the Tai Chi group compared to the control group after chemoradiotherapy. The MFSI-SF total score was markedly correlated with the nLF/nHF ratio.
Tai Chi exercise is conducive to alleviate CRF in NPC patients undergoing chemoradiotherapy. The improvement in ANS balance might fit into the process of Tai Chi for CRF management in this population.
Until now, the recognition of sodium taurocholate cotransporting polypeptide (NTCP) deficiency has been mainly based on sporadic case reports. It was previously believed to be mildly symptomatic and ...resulting in mild liver dysfunction. However, to our knowledge, there have been no reports about the histopathologic and ultrastructural pathologic characteristics of the disease. The aim of the study was to analyze the clinical, histopathologic and ultrastructural pathologic characteristics of NTCP deficiency in 13 pediatric patients.From August 2012 to October 2018, this retrospective study conducted in the Department of Pediatrics of Tongji Hospital, China analyzed the data of 13 NTCP deficient patients with an SLC10A1 gene mutation. Except for NTCP deficiency, no other liver diseases were present in the patients, which was determined by both a genetic testing panel for jaundice and by reviewing medical records. The laboratory results, imaging, histopathologic, and ultrastructural pathologic information were recorded for analysis.The serum level of total bile acid was high in all 13 patients. All patients had adequate growth and development. Eight of the patients (8/13) presented with visible jaundice and 12 (12/13) were found to have hyperbilirubinemia. A needle liver biopsy was performed in 11 cases, which revealed slightly chronic inflammation in all 11 patients. One of the patients (1/13) was found to be suffering from gallstones.The data showed that although NTCP deficiency was often asymptomatic, some of the patients showed obvious clinical expressions, such as jaundice. Among the 13 pediatric patients with NTCP deficiency, both the biochemical and histopathologic features were similar to those of mild hepatocellular jaundice. In addition, it was determined that the clinical features in the patient with gallstones may have been caused by NTCP deficiency.
Evacuation path optimization (EPO) is a crucial problem in crowd and disaster management. With the consideration of dynamic evacuee velocity, the EPO problem becomes nondeterministic polynomial-time ...hard (NP-Hard). Furthermore, since not only one single evacuation path but multiple mutually restricted paths should be found, the crowd evacuation problem becomes even challenging in both solution spatial encoding and optimal solution searching. To address the above challenges, this article puts forward an ant colony evacuation planner (ACEP) with a novel solution construction strategy and an incremental flow assignment (IFA) method. First, different from the traditional ant algorithms, where each ant builds a complete solution independently, ACEP uses the entire colony of ants to simulate the behavior of the crowd during evacuation. In this way, the colony of ants works cooperatively to find a set of evacuation paths simultaneously and thus multiple evacuation paths can be found effectively. Second, in order to reduce the execution time of ACEP, an IFA method is introduced, in which fractions of evacuees are assigned step by step, to imitate the group-based evacuation process in the real world so that the efficiency of ACEP can be further improved. Numerical experiments are conducted on a set of networks with different sizes. The experimental results demonstrate that ACEP is promising.
In this paper, we investigate the activity of atmospheric turbulence in the MLT region and the relationship between the activity of atmospheric turbulence and atmospheric wave activity. We use data ...from the Langfang MF radar (39.4∘N, 116.7∘E) from July 2019 to June 2020 and NRLMSIS 2.0 to calculate the parameters of atmospheric wave activity and atmospheric turbulence energy dissipation rate (ε). Atmospheric ε is modulated by different periods at different altitudes, and while there are 12 h and 24 h periods at all altitudes, the main period is different at different altitudes. A comparison of the ε with atmospheric tide activity shows that tides have an effect on ε, and the influence of tides on ε may be different at different altitudes. The pattern of variation in ε is similar to that of the atmospheric activity of the gravity wave, with both ε and the atmospheric activity of the gravity wave showing significant semi-annual variation.
Veratrum taliense is traditionally used TCMs in Yunnan province of China for pain and inflammation. Previous research and clinical applications have shown that V. taliense had significant analgesic ...activity. Jevine-type alkaloids were shown to be one of the anti-inflammatory and analgesic agents from V. taliense. However, other types of compounds from V. taliense related to its traditional use remains unknown.
To identify veratramine-type steroidal alkaloids with analgesic effects from the roots and rhizomes of V. taliense.
Compounds were isolated from the roots and rhizomes of V. taliense by chromatographic separation. Their structures were elucidated based on UV, IR, NMR and MS spectra data. Analgesic activity was assessed with acetic acid-induced writhing in mice model.
Seven new veratramine-type alkaloids were isolated from the roots and rhizomes of V. taliense. They all exhibited significant analgesic activity, of which alkaloids 1 and 4 were more potent antalgic than the well-known analgesic drug, pethidine.
The veratramine-type alkaloids from V. taliense may serve as new leads for the discovery of analgesic drugs.
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