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The national status and dose trends on the occupational exposure to ionizing radiation in industrial practices for 2009-2018 in China are presented in terms of seven occupational categories. A total of 504,538 industrial radiation workers were monitored for the period 2009-2018, with a continuous increase in the number of workers from 23,789 in 2009 to 66,017 in 2018. The annual average effective doses were 0.399, 0.425, 0.392, 0.376, 0.346, 0.355, 0.312, 0.305, 0.270, and 0.230 mSv from 2009 to 2018, respectively, which were well lower than the recommended occupational dose limit of 20 mSv y-1 for radiation workers. The Mann-Kendall test result shows a statistically significant decreasing trend at a rate of 0.02 mSv y-1 in average annual effective doses (p

Zhou, W., 2020. Economic marketing of marine leisure tourism based on internet of things. In: Li, L. and Huang, X. (eds.), Sustainable Development in Coastal Regions: A Perspective of Environment, Economy, and Technology. Journal of Coastal Research, Special Issue No. 112, pp. 87-89. Coconut Creek (Florida), ISSN 0749-0208.As a result of the implementation and promotion of the marine strategy, the marine leisure tourism economy has achieved rapid development and brought new opportunities to the optimization of the marine economic industry. However, there are still many deficiencies and problems in the current economic marketing of marine leisure tourism, which limit the further development of marine leisure tourism economy and urgently need reform and improvement. Based on this, this paper first analyzes the important role of marine leisure tourism based on the Internet of things, then studies the current situation and problems of economic marketing of marine leisure tourism, and finally gives the economic marketing strategy of marine leisure tourism based on the Internet of things.

Epidemiological studies on residential radon exposure and the risk of histological types of lung cancer have yielded inconsistent results. We conducted a meta-analysis on this topic and updated previous related meta-analyses. We searched the databases of Cochrane Library, Embase, PubMed, Web of Science and Chinese National Knowledge Infrastructure for papers published up to 13 November 2018. The pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed and random effects models. Subgroup and dose‒response analyses were also conducted. This study was registered with PROSPERO (No. CRD42019127761). A total of 28 studies, which included 13,748 lung cancer cases and 23,112 controls, were used for this meta-analysis. The pooled OR indicated that the highest residential radon exposure was significantly associated with an increased risk of lung cancer (OR = 1.48, 95% CI = 1.26–1.73). All histological types of lung cancer were associated with residential radon. Strongest association with small-cell lung carcinoma (OR = 2.03, 95% CI = 1.52–2.71) was found, followed by adenocarcinoma (OR = 1.58, 95% CI = 1.31–1.91), other histological types (OR = 1.54, 95% CI = 1.11–2.15) and squamous cell carcinoma (OR = 1.43, 95% CI = 1.18–1.74). With increasing residential radon levels per 100 Bq/m3, the risk of lung cancer, small-cell lung carcinoma and adenocarcinoma increased by 11%, 19% and 13%, respectively. This meta-analysis provides new evidence for a potential relationship between residential radon and all histological types of lung cancer.

Toll-like receptors (TLRs) are expressed in Sertoli cells and Leydig cells and can initiate testicular innate immune responses. The A-kinase anchor protein 3 (AKAP3), a family of scaffolding protein, was reported to be expressed only in testis and plays important regulatory roles during spermatogenesis. Our present study aimed to investigate the differential expression of TLRs family and AKAP3 in cigarette smoked Kunming mice testis. To check the effect of cigarette smoke, mice were randomly divided (n = 5 each) and exposed to cigarette smoke (2 hr/day with 10 cigarettes) for six consecutive days followed by one exposure-free day. The exposure lasted for zero (control), 1, 3, 5 and 7 months respectively. The IHC results showed that expression of AKAP3 protein is mainly located in sperm cells and the mean density of which was significantly lower than that of control mice. Real-time PCR results showed that expression of AKAP3 was significantly increased at early CS exposure (1 month) and then returned to normal in subsequent months. TLR2-7, TLR13, Myd88 and Traf6 mRNA expression are much lower compared to control, especially after 3-month cigarette smoke exposure, the time of which is almost consistent with sperm cycle. The present study suggests that TLR signal pathway and AKAP3 may play roles in spermatogenesis.

To obtain active lipases for biodiesel production by refolding Proteus sp. lipase inclusion bodies expressed in E. coli. A lipase gene lipPN1 was cloned from Proteus sp. NH 2-2 and expressed in E. coli BL21(DE3). Non-reducing SDS-PAGE revealed that recombinant LipPN1(rLipPN1) were prone to form inclusion bodies as disulfide-linked dimers in E. coli. Site-directed mutagenesis confirmed that Cys85 in LipPN1 was involved in the dimer formation. After optimizing the inclusion body refolding conditions, the maximum lipase activity reached 1662 U/L. The refolded rLipPN1 exhibited highest activity toward p-nitrophenyl butyrate at pH 9.0 and 40 °C. It could be activated by Ca2+ with moderate tolerance to organic solvents. It could also convert soybean oil into biodiesel at a conversion ratio of 91.5%. Preventing the formation of disulfide bond could enhance the refolding efficiency of rLipPN1 inclusion bodies.

Microcystins (MCs) are highly liver-specific and evidenced as a liver tumor promoter. Oxidative stress is one of the most important toxicity mechanisms of MCs, which is tightly related to oxygen concentration. The effects of MCs on animals and cell lines in normoxia and the mechanisms have been well studied, but such effects in different oxygen conditions were still unclear. The aim of the present study was to explore the cellular response of the human hepatocellular carcinoma cell line (HepG2) to MC-LR exposure under hypoxic (1% O-2) and normoxic (21% O-2) conditions. We examined cell viability, mitochondrial membrane potential (MMP), superoxide dismutase (SOD) activity and gene expression posttoxin exposure. Cell viability was increased by MC-LR in normoxia although decreased in hypoxia. MC-LR markedly induced MMP loss under hypoxic condition but only slightly MMP loss under normoxic condition. SOD activity was significantly induced by MC-LR in hypoxia, indicating prolonged oxidative stress. Inhibitory apoptosis protein (c-IAP2) was significantly up-regulated by MC-LR under normoxic condition, suggesting that c-IAP2 played an important role in the promotion of cell proliferation by MC-LR. These results indicate that MC-LR promotes cell proliferation under normoxic condition whereas induces cell apoptosis under hypoxic condition. Copyright (C) 2012 John Wiley & Sons, Ltd.

Microcystins (MCs) can cause evident hepatic apoptosis. In vitro studies indicated that uptake of MC by isolated hepatocytes was dramatically reduced as ambient temperature dropped, and some studies presented a hypothesis that differences in core body temperatures in animals result in diverse uptake of MC, as well as different toxic effects. Thus far, however, few in vivo studies have been conducted to investigate the effects of temperature on MC-induced hepatocyte apoptosis in fish, a typical poikilotherm. In the present study, zebrafish were treated with MC-LR, an MC metabolite, at three water temperatures (12, 22 and 32 degrees C), and evident differences in apoptotic profiles were observed. Damage to liver ultrastructures revealed temperature-dependent early-stage patterns of apoptosis. Flow-cytometric analysis indicated that hepatocyte apoptotic rates varied with a temperature-dependent effect. The transcription levels of some apoptosis-related genes were determined using quantitative real-time polymerase chain reaction, and significantly elevated gene expressions of P53, Bcl-2, Bax and caspase-3 were found in the 12 and 32 degrees C groups. Results of the present study indicate that different ambient temperatures can lead to various toxic effects of MCs on hepatic apoptosis in fish. Copyright (c) 2012 John Wiley & Sons, Ltd.

Toxic cyanobacterial blooms, which produce cyclic heptapeptide toxins known as microcystins, are worldwide environmental problems. On the other hand, the cyanobacteria protein (30–50%) has been recommended as substitute protein for aquaculture. The present laboratory study verified the feasibility of cyanobacteria protein substitution and risk assessment. Goldfish were fed diets supplemented lyophilised cyanobacteria powder for 16 weeks with the various doses: 0% (control), 10%, 20%, 30% and 40%. Low doses (10% and 20%) promoted growth whereas high doses (30% and 40%) inhibited growth. In cyanobacteria treated fish, the proximate composition of ash, crude fat content and crude protein content decreased in 16 weeks; the saturated fatty acid (SFA) content significantly increased; the n-3 polyunsaturated fatty acid content, collagen content and muscle pH significantly decreased; cooking loss percents increased significantly. Muscle fiber diameter and myofibril length were negatively correlation. Additionally, flavour compounds (e.g., amino acids, nucleotides, organic acids and carnosine) changed significantly in the treated fish and odour compounds geosmin and 2-methylisoborneol increased significantly. The estimated daily intake (EDI) of microcystins in muscle was close to or exceeded the World Health Organization (WHO) tolerable daily intake (TDI), representing a great health risk. Cyanobacterie is not feasible for protein sources use in aquaculture.

Microcystins (MCs) cause normocytic anemia in patients in a hemodialysis unit in Caruaru, Brazil in 1996, but the underlying mechanisms are still unclear. In the present study, Balb/c mice were intraperitoneally injected with microcystin-LR (MC-LR) at the doses of 0.5, 2 and 8 mu/kg body weight (bw) every 48 h for 30d. After the prolonged exposure of MC-LR, significant decreases of red blood cell count (RBC), hemoglobin (Hb) and hematocrit (Ht) were observed in 2 and 8 mu g/kg bw groups, but erythrocyte mean corpuscular volume (MCV) showed no significant changes. Significantly elevated micronucleus frequency was observed in bone marrow cells (BMCs) in all MC-LR treatments. The proliferation of BMCs significantly declined in both 2 and 8 mu g/kg bw groups. Serum levels of some hematopoietic growth factors significantly changed in 8 mu g/kg bw group, mainly including granulocyte-macrophage (GM-CSF), erythropoietin (EPO), interleukin-3 (IL-3) and TNF-alpha. The transcriptional levels of these 4 genes in BMCs were also significantly changed in 8 mu g/kg bw group. MC-LR exposure significantly increased the apoptosis rates in all MC-LR treatments. The present study indicates prolonged exposure of MC-LR induces normocytic anemia, and the disturbed hematopoietic growth factors and BMCs apoptosis are responsible for this normocytic anemia. (C) 2013 Elsevier Ireland Ltd. All rights reserved.

With the high penetration of distributed generations (DG) in low voltage (LV) distribution network, some power quality problems, such as harmonic impacts due to power electronics converters, are unavoidable. This paper analyzes the harmonic influence caused by DG inverters to the connection points and to other nodes in the network. The LV distribution network model with DG inverters is established by MATLAB/Simulink. And simulation results verify the analysis. Power quality issues of connection point when multiple DG inverters connected to LV network are presented in field measurements and some related problems are discussed.

In this paper, models of distributed generations and distribution network are built in MATLAB and simulation results under several cases are given. An equivalent mathematical model at access point of distributed generation is built, based on which, the propagation mechanisms of harmonics produced by distributed generations in distribution network is analyzed. It is concluded that THDi may be no more suitable for harmonic evaluation in distributed network containing distributed generations. This paper provides some reference value for analyzing and managing harmonics.

Microcystins (MCs) are highly liver-specific and evidenced as a liver tumor promoter. Oxidative stress is one of the most important toxicity mechanisms of MCs, which is tightly related to oxygen concentration. The effects of MCs on animals and cell lines in normoxia and the mechanisms have been well studied, but such effects in different oxygen conditions were still unclear. The aim of the present study was to explore the cellular response of the human hepatocellular carcinoma cell line (HepG2) to MC-LR exposure under hypoxic (1% O2 ) and normoxic (21% O2 ) conditions. We examined cell viability, mitochondrial membrane potential (MMP), superoxide dismutase (SOD) activity and gene expression posttoxin exposure. Cell viability was increased by MC-LR in normoxia although decreased in hypoxia. MC-LR markedly induced MMP loss under hypoxic condition but only slightly MMP loss under normoxic condition. SOD activity was significantly induced by MC-LR in hypoxia, indicating prolonged oxidative stress. Inhibitory apoptosis protein (c-IAP2) was significantly up-regulated by MC-LR under normoxic condition, suggesting that c-IAP2 played an important role in the promotion of cell proliferation by MC-LR. These results indicate that MC-LR promotes cell proliferation under normoxic condition whereas induces cell apoptosis under hypoxic condition.

Microcystins (MCs) can cause evident hepatic apoptosis. In vitro studies indicated that uptake of MC by isolated hepatocytes was dramatically reduced as ambient temperature dropped, and some studies presented a hypothesis that differences in core body temperatures in animals result in diverse uptake of MC, as well as different toxic effects. Thus far, however, few in vivo studies have been conducted to investigate the effects of temperature on MC-induced hepatocyte apoptosis in fish, a typical poikilotherm. In the present study, zebrafish were treated with MC-LR, an MC metabolite, at three water temperatures (12, 22 and 32 °C), and evident differences in apoptotic profiles were observed. Damage to liver ultrastructures revealed temperature-dependent early-stage patterns of apoptosis. Flow-cytometric analysis indicated that hepatocyte apoptotic rates varied with a temperature-dependent effect. The transcription levels of some apoptosis-related genes were determined using quantitative real-time polymerase chain reaction, and significantly elevated gene expressions of P53, Bcl-2, Bax and caspase-3 were found in the 12 and 32 °C groups. Results of the present study indicate that different ambient temperatures can lead to various toxic effects of MCs on hepatic apoptosis in fish.

Fish suffer from anemia and hypovolemic hypotensive shock after in vivo exposure with microcystins. However, except for in vivo causes for anemia and hypotension, an in vitro study of fish erythrocytes exposed to MC is necessary. For a better understanding of hematology toxicity of MC, the main aim of the present study was to investigate the toxic effects of microcystin on fish erythrocytes in vitro. Crucian carp erythrocytes were incubated in vitro with microcystin-LR (MC-LR) at doses of 0, 1, 10, 100 and 1,000 nM. The level of lipid peroxidate significantly increased in MC-LR treatment groups. Glutathione decreased after exposure to MC-LR. The activities of antioxidative enzymes, including superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferase, were significantly increased after exposure with MC-LR. The hemolysis was significantly increased, while the activities of acetylcholinesterase, Na+–K+-ATPase and Ca2+–Mg2+-ATPase were significantly decreased. In addition, pathological alterations in agglomerated and jagged erythrocytes were observed in blood smears. The findings indicate that damages to erythrocytes should also be responsible for anemia and hypotensive shock or even death.