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Does asymmetric nexus exist between agricultural land and the housing market? Evidence from non-linear ARDL approach
2019
Uzuner, Gizem | Adewale, Andrew Alola
Expectedly, urbanization is often associated with constant degradation of natural habitat. In most cases, as demand for housing increases, natural habitat like agricultural land, forestry, and water bodies gradually gives way to building structures. Against this backdrop, the current study investigates the asymmetric nexus of agricultural land and housing market vis-à-vis house prices. The study employed the yearly data from 1976 to 2015 for the case of Sweden and used economic policy uncertainty (EPU) as a control variable in non-linear autoregressive distributed lag (NARDL) approach. The finding notes a significant and positive short- and long-run relationship between housing price and agricultural land especially when there is a negative shock on agricultural land. But when there is a negative shock on EPU, the impact on housing price is significant and negative for both short run and long run. While an asymmetric long-run relationship is significant and positive between EPU and housing price, such significant occurrence do not exist for agricultural land. Hence, in meeting housing demand and mitigating an escalated growth in house prices, implementation of effective land use policy is encouraged.
Afficher plus [+] Moins [-]Evaluating gas chromatography with a halogen-specific detector for the determination of disinfection by-products in drinking water
2019
Andersson, Anna | Ashiq, Muhammad Jamshaid | Shoeb, Mohammad | Karlsson, Susanne | Bastviken, David | Kylin, Henrik
The occurrence of disinfection by-products (DBPs) in drinking water has become an issue of concern during the past decades. The DBPs pose health risks and are suspected to cause various cancer forms, be genotoxic, and have negative developmental effects. The vast chemical diversity of DBPs makes comprehensive monitoring challenging. Only few of the DBPs are regulated and included in analytical protocols. In this study, a method for simultaneous measurement of 20 DBPs from five different structural classes (both regulated and non-regulated) was investigated and further developed for 11 DBPs using solid-phase extraction and gas chromatography coupled with a halogen-specific detector (XSD). The XSD was highly selective towards halogenated DBPs, providing chromatograms with little noise. The method allowed detection down to 0.05 μg L⁻¹ and showed promising results for the simultaneous determination of a range of neutral DBP classes. Compounds from two classes of emerging DBPs, more cytotoxic than the “traditional” regulated DBPs, were successfully determined using this method. However, haloacetic acids (HAAs) should be analyzed separately as some HAA methyl esters may degrade giving false positives of trihalomethanes (THMs). The method was tested on real water samples from two municipal waterworks where the target DBP concentrations were found below the regulatory limits of Sweden.
Afficher plus [+] Moins [-]Asteraceae species as potential environmental factors of allergy
2019
Denisow-Pietrzyk, Marta | Pietrzyk, Łukasz | Denisow, Bożena
The statistics from Europe and the USA have proven a high risk for skin diseases associated with plant contact. Therefore, plant-induced dermatitis is of increasing attention in dermatology. The focus of this paper was to present the current knowledge on aspects of contact allergy related to Asteraceae (Compositae) species. The Asteraceae family is one of the largest in the world with members across all continents. The PubMed/Medline databases have been searched. The Asteraceae representatives consist of diverse secondary metabolites, which exhibit various advantageous effects in humans. In particular, sesquiterpene lactones (SLs) may cause sensitization resulting in skin irritation and inflammation. In this study, we tried to reveal the allergenic potential of several Asteraceae species. The Asteraceae-related allergy symptoms involve eczema, hay fever, asthma, or even anaphylaxis. Furthermore, the evidence of severe cross-reactivity with food and pollen allergens (PFS) in patients sensitive to Asteraceae allergens have been announced. Further identification and characterization of secondary metabolites and possible allergens in Asteraceae are necessary for the better understanding of Asteraceae-related immune response. The Asteraceae allergy screening panel (the SL mix and the Compositae mix of five plant species) is a promising tool to improve allergy diagnostics and therapy.
Afficher plus [+] Moins [-]Electrochemical anodization of graphite oxide-TiO2 nanotube composite for enhanced visible light photocatalytic activity
2019
Ali, Imran | Park, Kyungmin | Kim, Seu-Run | Kim, Jong-Oh
The electrochemical anodization method was used to dope graphite oxide (GO) onto TiO₂ nanotubes (TNTs). This study focused on enhancement of the photocatalytic activity of TNTs in the visible light region. In this study, we have checked the effect of different GO concentrations and effect of GO doping time on photocatalytic efficiency of composite. The photocatalytic activity of the GO-TNT composite was tested by degradation of an organic compound. The organic compound was most severely degraded (95%) when the GO-TNT catalyst was doped at an anodization of 60 V for 13 min and GO concentration of 0.25 g L⁻¹. This degradation was 5.6 times higher than that of bare TiO₂. The as-prepared catalyst was characterized using FE-SEM, XRD, AES, PL, UV-Vis DRS, and Raman analysis. Recycling of the GO-TNT composite was also performed in order to examine the stability of the visible light catalyst. We observed that the doping of GO on the TNT surface can enhance the photocatalytic efficiency under visible light. Graphene acts as an electron transport; therefore, GO-TNTs were favorable for the separation of e⁻ and h⁺ charges. This promoted the formation of OH radicals, h⁺, and superoxides, all of which degrade organics.
Afficher plus [+] Moins [-]Concentrations and emissions of particulate matter and ammonia from extensive livestock farm in South China
2019
Dai, Chunhao | Huang, Shaojian | Zhou, Yaoyu | Xu, Bin | Peng, Hui | Qin, Pufeng | Wu, Genyi
Atmospheric particulate matter (PM) and ammonia pollution from livestock feeding have gradually become the environmental concerns due to the spring up of livestock farms in worldwide. However, researches about the formation of atmospheric particulate matter related to ammonia are still limited. Therefore, a study to survey the total suspended particles (TSP), PM with the diameter less than 10 μm (PM₁₀), PM₄, PM₂.₅, PM₁, and ammonia was conducted at four types of hog houses distinguished by its building design as well as manure handling methods in South China. Four hog houses were monitored during three fattening periods from 2016 to 2017. The emissions of NH₃ per hog house averaged 210.42 μg s⁻¹. The emissions of PM per hog house averaged 2.017 μg h⁻¹ for PM₁, 2.149 μg h⁻¹ for PM₂.₅, 2.305 μg h⁻¹ for PM₄, 3.950 μg h⁻¹ for PM₁₀, and 9.317 μg h⁻¹ for TSP. The emissions of PM per hog house average 2.017 μg h⁻¹, 2.149 μg h⁻¹, 2.305 μg h⁻¹, 3.950 μg h⁻¹, and 9.317 μg h⁻¹, respectively for PM₁, PM₂.₅, PM₄, PM₁₀, and PM₁₀. In each hog house, while the quantity of manure determined the concentration of NH₃, biological fermentation bed was able to control the ammonia volatilization compared with other three manure handling methods. The largest percentage of fine PM (< 10 μm) is produced by the manual waterless method for manure handling. When it came to the manual waterless method, largest amount of fine PM (< 10 μm) was founded to form. Among various contributions of secondary inorganic PM to PM₁, the NH₃ was a dominant factor. Based on our experiment, the absolute concentration of NH₃ was inversely proportional to the concentration of PM₁ when the background influence was removed.
Afficher plus [+] Moins [-]Correction to: Occurrence of 25 pharmaceuticals in Taihu Lake and their removal from two urban drinking water treatment plants and a constructed wetland
2019
Hu, Xia-Lin | Bao, Yi-Fan | Hu, Jun-Jian | Liu, You-Yu | Yin, Da-Qiang
The article Occurrence of 25 pharmaceuticals in Taihu Lake and their removal from two urban drinking water treatment plants and a constructed wetland, written by Xia-Lin Hu, Yi-Fan Bao, Jun-Jian Hu, You-Yu Liu and Da-Qiang Yin, was originally published electronically on the publisher’s internet portal
Afficher plus [+] Moins [-]Evaluating methods to detect and monitor populations of a large invasive lizard: the Argentine giant tegu
2019
Engeman, Richard M. | Kaiser, Bernard W. | Osorio, Kimberly J.
The Argentine giant tegu, a large lizard native to South America, was first discovered as established in the USA in scrub habitats of west-central Florida in 2006. Invasive populations potentially could occupy an extensive range of habitats and in much of the southern United States and Mexico and threaten many native species. The Argentine giant tegu was recently deemed as having a “highest impact concern” among the invasive reptile species most threatening to Florida ecology. Among the most rewarding research directions identified for this species was “having a reliable and practical method to detect/monitor” them. We address this need by evaluating five methods for monitoring Argentine giant tegus on how well each method detected the species and whether the observations were sufficient to quantitatively assess population abundance using a widely applicable framework for indexing animal populations. Passive tracking plots were the most efficient and effective means for detecting tegus and calculating abundance indices but were best suited for late winter to spring before summer rains compacted tracking substrates. Gopher tortoise burrows are often used by tegus and camera traps on their entrances proved able to obtain data suitable for indexing populations but required more labor and expense than tracking plots. Trapping either at gopher tortoise burrows or along drift fences was ineffective at capturing tegus. Similarly, visual encounter transects were not effective for observing tegus.
Afficher plus [+] Moins [-]Pyrene degradation by marine-derived ascomycete: process optimization, toxicity, and metabolic analyses
2019
Vasconcelos, Maria R. S. | Vieira, Gabriela A. L. | Otero, Igor V. R. | Bonugli-Santos, Rafaella C. | Rodrigues, Marili V. N. | Rehder, Vera L. G. | Ferro, Milene | Boaventura, Sinésio | Bacci, Maurício Jr | Sette, Lara D.
Marine-derived fungi are relevant genetic resources for bioremediation of saline environments/processes. Among the five fungi recovered from marine sponges able to degrade pyrene (Py) and benzo[a]pyrene (BaP), Tolypocladium sp. strain CBMAI 1346 and Xylaria sp. CBMAI 1464 presented the best removal rates of Py and BaP, respectively. Since the decrease in BaP was related to mycelial adsorption, a combined strategy was applied for the investigation of Py degradation by the fungus Tolypocladium sp. CBMAI 1346. The selected fungus was able to degrade about 95% of Py after 7 days of incubation (optimized conditions), generating metabolites different from the ones found before optimization. Metabolites and transcriptomic data revealed that the degradation occurred mainly by the cytochrome P450 pathway. Putative monooxygenases and dioxygenases found in the transcriptome may play an important role. After 21 days of degradation, no toxicity was found in the optimized culture conditions. The findings from the present study highlight the potential of marine-derived fungi to degrade environmental pollutants and convey innovative information related to the metabolism of pyrene.
Afficher plus [+] Moins [-]Arsenic exposure intensifies glycogen nephrosis in diabetic rats
2019
Sertorio, Marcela Nascimento | Souza, Ana Cláudia Ferreira | Bastos, Daniel Silva Sena | Santos, Felipe Couto | Ervilha, Luiz Otávio Guimarães | Fernandes, Kenner Morais | de Oliveira, Leandro Licursi | Machado-Neves, Mariana
It is known that either arsenic exposure or diabetes can impact renal function. However, it is unclear how these combined factors may influence kidney functions. Therefore, we evaluated morphological, functional, and oxidative parameters in the kidney of diabetic rats exposed to arsenic. Healthy male Wistar rats and streptozotocin-induced diabetic rats were exposed to 0 and 10 mg/L arsenate through drinking water for 40 days. Renal tissue was assessed using morphometry, mitosis and apoptosis markers, mineral proportion, oxidative stress markers, as well as the activity of antioxidant enzymes and membrane-bound adenosine triphosphatases. Arsenate intake altered glucose levels in healthy animals, but it did not reach hyperglycemic conditions. In diabetic animals, arsenate led to a remarkable increase of glycogen nephrosis in distal tubules. In these animals, additionally, the activity of catalase and glutathione S-transferase, besides the proportion of Fe, Cu, and K in renal tissue, was altered. Nevertheless, arsenate did not accumulate in the kidney and did not impact on other parameters previously altered by diabetes, including levels of malondialdehyde, Na, urea, creatinine, and apoptosis and mitosis markers. In conclusion, besides the intensification of glycogen nephrosis, the kidney was able to handle arsenate toxicity at this point, preventing arsenic deposition in the exposed groups and the impairment of renal function.
Afficher plus [+] Moins [-]Atrazine exposure in gestation and breastfeeding affects Calomys laucha sperm cells
2019
Saalfeld, Graciela Quintana | Varela Junior, Antônio Sergio | Castro, Tiane | Pires, Diego Martins | Pereira, Jéssica Ribeiro | Pereira, Fernanda Alves | Corcini, Carine Dahl | Colares, Elton Pinto
The present study evaluated the effects of low doses of atrazine administered during gestation and breastfeeding on sperm characteristics of the wild rodent Calomys laucha. Adult females were divided into groups of 10 and administered different doses of atrazine through gavage, during gestational or breastfeeding period. At 3 months of age, the F1 adult male progeny of these females was evaluated. We observed a drastic reduction in the total and progressive motility of male sperm cells at all doses and during both the exposure periods. Moreover, the plasma membrane integrity of adult male sperm cells decreased at all doses of atrazine administered during the breastfeeding, whereas the membrane fluidity of these cells increased at all tested doses. Atrazine led to a decrease in the sperm mitochondrial functionality at all doses and during both exposure periods. The damage to the sperm DNA was higher in males exposed to the highest dose (1.0 mg/kg) during the gestation period, and in animals exposed to the lowest dose of atrazine (0.1 mg/kg) during breastfeeding period. Furthermore, the highest dose (1.0 mg/kg) of atrazine reduced the sperm concentration. Furthermore, the reduced levels of reactive oxygen species (ROS) were observed at all evaluated doses in males exposed during the gestation period. These results suggest that the administration of low doses of atrazine at critical periods of development may permanently reduce the sperm quality in C. laucha.
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