خيارات البحث
النتائج 3981 - 3990 من 4,937
The impact of textual and pictorial warnings on tumbac (waterpipe tobacco) boxes on the motivation and intention to quit waterpipe smoking in Lebanon: a cross-sectional study النص الكامل
2019
Hallit, Souheil | Layoun, Nelly | Malaeb, Diana | Outayek, Miguella | Boueid, Marie-Josée | Waked, Mirna | Bacha, Zeina Aoun | Salameh, Pascale
Few published studies have examined the impact of waterpipe tobacco pictorial health warnings worldwide but none of these papers assessed the motivation and intention to quit among Lebanese waterpipe smokers. To examine factors associated with the motivation and intention to quit waterpipe smoking (WS) in Lebanon, particularly the impact of textual vs. pictorial warnings on tumbac boxes. A cross-sectional study was conducted between January and May 2018, involving 520 participants. Having smokers at work (OR = 0.92) and increasing number of waterpipes per week (ORa = 0.94) were associated with decreased motivation to quit WS. Thinking that shocking images on tumbac packages would have more effect than textual warnings (ORa = 2.96) and those who would change the tumbac if the company decides to change the look of the box with shocking images about health damage (ORa = 1.98) were significantly associated with increased motivation to quit WS. Having a high motivation (ORa = 2.61), thinking that using shocking images on tumbac boxes can have more effect than textual warnings (ORa = 2.12), those who stopped smoking because of the warnings (ORa = 2.62), those who would choose pictorial warnings alone (ORa = 2.11), and both pictorial and textual warnings (ORa = 3.41) on tumbac packages were associated with higher intention to quit WS in two months. Pictorial and textual warnings on tumbac packs were associated with higher intention and motivation to stop WS. Public health education programs for this purpose seem warranted.
اظهر المزيد [+] اقل [-]Metabolism of obeticholic acid in brown bullhead (Ameiurus nebulosus) النص الكامل
2019
Mach, Samuel | Jegorov, Alexandr | Šimek, Zdeněk
Analysis of brown bullhead (Ameiurus nebulosus) bile by ultra performance liquid chromatography high-resolution mass spectrometry (UPLC/HRMS) revealed a series of bile acids similar to those found in humans. Accordingly, we chose this fish as a model organism to examine the metabolism of obeticholic acid, a bile acid used to treat a number of human liver diseases and the one that has the potential to occur as an environmental contaminant. The taurine and glycine conjugates of obeticholic acid and keto-obeticholic acid were identified, as well as the D-cysteinolic acid conjugate of obeticholic acid, likely a metabolite specific to fish. In addition, metabolites of obeticholic acid (sulphate and glucuronide) and several hydroxy-obeticholic acid derivatives were found, representing typical pathways of primary and secondary steroid metabolism. Brown bullhead exposed to obeticholic acid at a dose of 100 mg/kg gave no overt signs of distress or toxicity.
اظهر المزيد [+] اقل [-]Testing the impact of real interest rate, income, and energy consumption on Turkey’s CO2 emissions النص الكامل
2019
Isiksal, Aliya Zhakanova | Samour, Ahmed | Resatoglu, Nil Gunsel
This paper aims to explore the impact of real interest rates (RIN), income, trade, foreign direct investment (FDI), and energy consumption on Turkey’s carbon dioxide emissions (CO₂) over the period from 1980 to 2014. This study differs from the existing literature by introducing a new discussion in the determination of environmental degradation, namely real interest rate. Hatemi-J (HJ) cointegration with two structural breaks and the newly developed Bayer–Hanck (BH) combined cointegration tests are used to enhance and support the robustness of the autoregressive distributed lag (ARDL) bounds test. The Granger causality test within the vector error correction model (VECM) is employed to examine the causality direction among the variables in both the short and long run. The empirical results demonstrate that RIN negatively effects CO₂ emissions. This impact is also supported through energy, income, and FDI channels. It is suggested that policy makers should promote the stability of the real interest rates channel to reduce CO₂ emissions and encourage the renewable energy investment through the production of electricity using renewable sources.
اظهر المزيد [+] اقل [-]Lead (Pb) in the tissues of Anatidae, Ardeidae, Sternidae and Laridae of the Northern Hemisphere: a review of environmental studies النص الكامل
2019
Korbecki, Jan | Gutowska, Izabela | Chlubek, Dariusz | Baranowska-Bosiacka, Irena
Due to the ability of birds to travel long distances in the air, the potential feeding area of each individual is much larger than that of typical terrestrial animals. This makes birds a convenient indicator of environmental lead (Pb) pollution over large areas, in particular areas of inland and coastal waters. The aim of this study was to assess the concentrations of Pb in various organs of water birds from a variety of locations. The focus was on ducks, geese and swans (Anatidae); herons and egrets (Ardeidae); terns (Sternidae); and gulls (Laridae). This article describes the level of lead in the most commonly studied tissue types: feathers, bones and the liver. The study also presents data concerning the concentration of lead in the eggs of water birds. The highest levels of lead pollution can be observed in China and Korea, related to their high level of industrialization. In Iran too, environmental lead pollution is high, likely due to the developed petrochemical industry. Lead pollution in Japan, as well as in Western European countries (Spain, France, Italy), seems to be much lower than in China, India or Iran. Nevertheless, the level of pollution in Europe is higher than satisfactory, despite the introduction of a number of bans related to, for example, the use of leaded petrol or lead-containing paints. Finally, the USA and Canada appear to be the areas with the lowest lead pollution, possibly due to their low population densities.
اظهر المزيد [+] اقل [-]MnO2-loaded microorganism-derived carbon for U(VI) adsorption from aqueous solution النص الكامل
2019
Liao, Wei | Wang, Huilin | Li, Feize | Zhao, Changsong | Liu, Jun | Liao, Jiali | Yang, Jijun | Yang, Yuanyou | Liu, Ning
A low-cost industrial microorganism, Saccharomyces cerevisiae, was employed as a precursor to synthesize carbon/MnO₂ composites (MMCs) via an oxidation-reduction reaction and one-step carbonization method for U(VI) adsorption. Scanning electron microscopy and nitrogen adsorption measurement indicated that the microorganism’s carbonization could form surface porous structure and increase the specific surface area. Batch experiments showed that the maximum U(VI) adsorption capacity of MMCs reached 207 mg g⁻¹ at [U(VI)]ᵢₙᵢₜᵢₐₗ = 25 mg L⁻¹ and pHᵢₙᵢₜᵢₐₗ = 4.5. The obtained thermodynamic and kinetic parameters suggested that the process is endothermic, spontaneous, and chemisorption. FTIR and X-ray photoelectron spectroscopy demonstrated that the surface hydroxyl groups of composites might be the reactive adsorption sites for U(VI). Additionally, 0.5 mol L⁻¹ HNO₃ solution could desorb ~ 95% uranium from U(VI)-loaded MMCs, and materials exhibited good regenerated availability. This study suggests that MMCs can be a potential adsorbent for U(VI) preconcentration and removal from radioactive wastewater.
اظهر المزيد [+] اقل [-]Preparation of ion exchange resin using soluble starch and acrylamide by graft polymerization and hydrolysis النص الكامل
2019
Zhang, Ming | Lan, Guihong | Qiu, Haiyan | Zhang, Tailiang | Li, Wenjing | Hu, Xiuqiong
Based on soluble starch and acrylamide by performing graft polymerization in aqueous solution and hydrolysis step, a low-cost ion exchange resin has been synthesized to remove the heavy metal ions of Cr³⁺ and Ni²⁺. The hydrolysis progresses by adding NaOH to convert -CONH₂ to -COONa, and the adsorption experiments confirmed that the functional group to adsorb heavy metals is -COO⁻, rather than -CONH₂. During the determination of heavy metal adsorption, the Na⁺ concentration diffused by SR-16 into the solution was also analysed to investigate the ion exchange process. The composition and morphology of SR-16 was characterized by FT-IR, SEM, elemental analyser and EDS, and the results showed that SR-16 has an excellent adsorption capacity to the removal of heavy metal pollution; the adsorption mechanism of SR-16 could be explained by ion exchange progress with -COONa attached on the network structure.
اظهر المزيد [+] اقل [-]Assessment of acute toxicity and cytotoxicity of fluorescent markers produced by cardanol and glycerol, which are industrial waste, to different biological models النص الكامل
2019
Pelizaro, Bruno Ivo | Braga, Felipe Camargo | Crispim, Bruno do Amaral | de Barros, Luiz Guilherme Maiolino Lacerda | Pessatto, Lucas Roberto | Oliveira, Edwin José Torres | Vani, Juliana Miron | de Souza, Antonio Pancrácio | Grisolia, Alexeia Barufatti | Antoniolli-Silva, Andréia Conceição Milan Brochado | de Lima, Dênis Pires | dos Santos Jaques, Jeandre Augusto | Beatriz, Adilson | Oliveira, Rodrigo Juliano
The amphyphylic triazoanilines recently synthesized 1-(4-(3-aminophenyl)-1H-1,2,3- triazole-1-yl)-3-(3-pentadecylphenoxy)propan-2-ol (1) and 1-(4-(4-aminophenyl)-1H- 1,2,3-triazole-1-yl)-3-(3-pentadecylphenoxy)propan-2-ol (2), synthesized from cardanol and glycerol, have photophysical properties which allow their use in the development of fluorescent biomarkers with applicability in the biodiesel quality control. Based on this, the present research evaluated the toxic effects of both compounds in different biological models through the investigation of survival and mortality percentages as a measure of acute toxicity on Daphnia similis and Oreochromis niloticus, larvicidal assay against Aedes aegypti, and cytotoxic activity on mammary cells. Results demonstrate that these triazoanilines 1 and 2 have shown low acute toxicity to the biological models investigated in this study up to the following concentrations: 4.0 mg L-1 (D. similis), 4.0 mg L-1 (A. aegypti larvae), 1.0 mg L-1 (O. niloticus), and 1.0 mg mL-1 (mammary cells). This fact suggests the potential for safe use of compounds 1 and 2 as fluorescent markers for the monitoring of biodiesel quality, even in the case of environmental exposure. Besides all of that, the reuse of cardanol and glycerol, both industrial wastes, favors the maintenance of environmental health and is in agreement with the assumptions of green chemistry. Graphical abstract ᅟ
اظهر المزيد [+] اقل [-]Physiological mechanisms of aluminum (Al) toxicity tolerance in nitrogen-fixing aquatic macrophyte Azolla microphylla Kaulf: phytoremediation, metabolic rearrangements, and antioxidative enzyme responses النص الكامل
2019
Chakraborty, Sindhunath | Mishra, Aditi | Verma, Ekta | Tiwari, Balkrishna | Mishra, Arun K. | Singh, Satya Shila
To investigate the extent of aluminum toxicity tolerance of eco-friendly, fast-growing, fresh water, pteridophytic Azolla–Anabaena symbiotic association in terms of altered physiological signals; Azolla microphylla Kaulf was exposed to 0 (control), 100, 250, 500, and 750 μM AlCl₃, at pH 4.5 for 6 days. The adversity of Al was increased in a dose-dependent manner and the highest was recorded at 750 μM AlCl₃. Despite the significant loss in membrane integrity (80% electrolyte leakage) due to an enhanced generation of H₂O₂, A. microphylla reflected only 50% growth inhibition (fresh and dry weight) at 500 μM AlCl₃ (LD₅₀). However, the average root length of Azolla was drastically reduced at high concentration due to their direct contact with aluminum-containing growth medium. Contrary to this, the whole association maintained moderate chlorophyll, carbohydrate content, photosynthetic efficiency, nitrogen-fixing ability, and nitrogen content at high Al concentration. Probably, growth protection was pertained through significant detoxification of H₂O₂ by employing an efficient antioxidative defense system including antioxidative enzymes (SOD, APX, and CAT) and non-enzymatic antioxidant carotenoids. An enhanced level of phenolics and flavonoids in the root exudates possibly maintained a non-toxic level of aluminum inside the cell (195.8 μg Al/g FW) which makes A. microphylla a suitable pteridophytic plant to not only remove toxic Al from the contaminated sites but also to improve nitrogen status of those regions. Graphical abstract ᅟ
اظهر المزيد [+] اقل [-]Assessment of ventilation noise impact from metro depot with over-track platform structure on workers and nearby inhabitants النص الكامل
2019
Tao, Ziyu | Wang, Yimin | Zou, Chao | Li, Qi | Luo, Yue
In order to alleviate the shortage of land use accompanied with urbanization, over-track building complexes above metro depots are developed rapidly in China, resulting in the larger mechanical ventilation needs in the metro depot. Excessive noise exposure caused by the huge ventilation system will bring serious impacts on the health of workers in the metro depot. This research intends to evaluate the noise annoyance in the metro depot and the noise influences on adjacent residential buildings by the ventilation system. A questionnaire survey of 100 people working in a metro depot of Guangzhou Metro Line 6 was conducted, and field measurements inside the metro depot and inside adjacent residential buildings were carried out. The environmental noise level in the metro depot and the ventilation fan–induced noise level inside adjacent residential buildings exceed the corresponding criterion limit of China. Dose-response relationship modeled by logistic function was used to assess the noise annoyance, which is found underestimating the percentage of “Annoyed” (% A) and percentage of “Little Annoyed” (% LA) of staffs in the metro depot, especially for the % LA. This may be attributed to the reducing reliability of dose-effect curves as the Ldₙ is higher than 65 dB(A). In order to alleviate the noise impact, noise-controlling measures need to be took. However, traditional noise-controlling measures cannot solve low-frequency noise disturbance.
اظهر المزيد [+] اقل [-]Analysis of swale factors implicated in pollutant removal efficiency using a swale database النص الكامل
2019
Fardel, Alexandre | Peyneau, Pierre-Emmanuel | Béchet, Béatrice | Lakel, Abdelkader | Rodriguez, Fabrice
Swales are traditional basic open-drainage systems which are able to remove stormwater-borne pollutants. In spite of numerous case studies devoted to their performances, parameters influencing the reduction of pollutant concentrations by swales remain elusive. In order to better characterize them, a database was set up by collecting performance results and design characteristics from 59 swales reported in the literature. Investigations on correlations among pollutant efficiency ratios (ERs) indicated that total trace metals (copper (Cu), zinc (Zn), cadmium (Cd), and lead (Pb)), total suspended solids (TSS), total phosphorus (TP), and total Kjeldahl nitrogen (TKN) exhibited many cross-correlated ERs. High ERs were observed for pollutants including a particulate form such as TSS (median ERs = 56%) and total trace metals (median ERs ≥ 62%), suggesting that these pollutants are efficiently trapped by sedimentation in swale bed and/or filtered within swale soil. Medium to high ERs were found for dissolved trace metals (median ERs ≥ 44%), whereas ERs for nutrient species were lower (median ERs ≤ 30%). The inflow concentration was identified as a major factor correlated to ER for most pollutants. For some pollutants, there is also a trend to get higher ER when the geometrical design of the swale increases the hydraulic residence time. Overall, this database may help to better understand swale systems and to optimize their design for improving pollutant removal.
اظهر المزيد [+] اقل [-]