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Investigating the role of origami algorithm in facades of high-rise buildings to reduce visual pollution and improve urban landscape quality 全文
2023
Tabbasom Tabasi | Amir Farajolahi Rod | Vahid Ahmadi | Hamid Reza Shoaei
The present study was conducted to identify and prioritize origami components affecting facades of high-rise buildings to explain the role of origami algorithm in improving urban landscape quality and reducing visual pollution. The research had an exploratory nature, and used the method of descriptive-survey data analysis. The research design was carried out in three steps, documentary analysis, Delphi survey and semiotic analysis. A panel of experts (n = 15) was considered as specialists in urban planning, architecture and urban design. Data were analyzed by statistical tests, SPSS-22 software and MAXQDA 2020 software. A hypothetical model of high-rise building made in RHINO software using Grasshopper plugin was applied for simulation. The results of the questionnaires revealed the effects of 18 components on the facade of high-rise buildings and also 12 components on the improvement of urban landscape quality. The findings indicated a correlation between overall dimensions of origami algorithm and urban landscape quality, and showed that the components of ârepetitionâ, âdetailsâ, âgeometryâ and ârhythmâ were most related to the origami algorithm, thereby highlighting the strong impact of the origami algorithm on improving urban landscape quality. According to the simulation results, among the components affecting urban landscape quality, âView compositionâ had the largest contribution with the correlation coefficient of 130, followed by âColorâ and âBalance and symmetryâ with the coefficients of 120. The end of this classification included the component âposition of openingsâ with the coefficient of 2.
显示更多 [+] 显示较少 [-]The role of microplastic aging on chlorpyrifos adsorption-desorption and microplastic bioconcentration 全文
2023
Ju, Hui | Yang, Xiaomei | Osman, Rima | Geissen, Violette
Microplastics (MPs) in soil undergo different aging processes such as photoaging, mechanical abrasion and biodegradation, leading to alterations in the surface properties of MPs. In this study, we investigated the adsorption-desorption of chlorpyrifos (CPF) on pristine and UV light-aged low-density polyethylene (LDPE) and biodegradable (Bio) MPs that were derived from plastic mulch films. We also tested the bioconcentration of pristine and aged MPs (LDPE- and Bio-MPs aged under UV light and LDPE-MPs aged in three different soils) associated with CPF by earthworms (Lumbricus terrestris). The results showed that UV-aged MPs showed higher CPF adsorption capacities than pristine MPs, with the adsorption capacities at 184.9 ± 5.3, 200.5 ± 1.8, 193.0 ± 8.7, and 215.9 ± 1.1 μg g−1 for pristine LDPE-, UV-aged LDPE-, pristine Bio- and UV-aged Bio-MPs, respectively. The desorption rate of CPF from UV-aged LDPE-MPs within 48 h was lower than the desorption from pristine ones (28.8 ± 7.7% vs. 40.0 ± 3.9%), while both pristine and UV-aged Bio-MPs showed very low CPF desorption rates. A 4-day Petri dish experiment showed that UV-aged MPs were significantly less concentrated in earthworm casts than pristine counterparts (52% and 36% lower for UV-aged LDPE- and Bio-MPs), while UV-aged MPs with adsorbed CPF were concentrated significantly more than UV-aged MPs without CPF. Interestingly, LDPE-MPs aged in soil with a high carbon, nitrogen, and carbon-to-nitrogen ratio were significantly more concentrated in earthworm casts than pristine LDPE-MPs. In conclusion, UV-aged MPs acted as stronger vectors for CPF than pristine MPs. The bioconcentration of MPs differed significantly due to microplastic aging, as well as the combined effect with CPF. Moreover, LDPE-MPs aged in soil with enriched carbon and nitrogen were significantly concentrated in earthworm casts. Further studies on the environmental behaviours of aged MPs associated with other pollutants in soil, especially soils high in carbon and nitrogen, are needed.
显示更多 [+] 显示较少 [-]Fractionation of levofloxacin and ofloxacin during their transport in NOM-goethite : Batch and column studies 全文
2023
Qin, Xiaopeng | Zhong, Xiaofei | Wang, Bin | Wang, Guangcai | Liu, Fei | Weng, Liping
Adsorption and transport of levofloxacin (LEV) and ofloxacin (OFL) enantiomers in a matrix containing goethite and natural organic matter (NOM) were investigated using batch and column experiments. In batch studies, competition and enantioselectivity were observed in the adsorption of LEV and OFL. Enantioselectivity upon adsorption was investigated by comparing changes in the enantiomer fraction (EF) (the ratio of LEV to the sum of LEV and OFL remaining in the solution) after and before adsorption. At pH < 7, there was hardly any selectivity in adsorption of OFL and LEV to goethite. At pH > 7, OFL showed a stronger adsorption than LEV to goethite, and this preference remained when NOM samples of Leonardite humic acid (LHA) and Elliott Soil fulvic acid (ESFA) were added. However, when Suwannee River NOM (SRNOM) was added, the preference was reversed, and LEV was adsorbed more strongly. In single systems, the presence of different types of NOM increased adsorption of LEV and OFL, especially LEV. In column studies, preloaded NOM decreased the transport of LEV and OFL through goethite-coated sand. The EF values in the effluent increased with retention time and reached the largest values (0.59–0.72) at around 1.5 pore volume (PV), and then decreased again, reaching a stable value at 5.0–30.0 PV. Both batch and column experiments showed that, fractionation of LEV and OFL occurred during adsorption and transport in the presence of NOM-goethite complexes, which would eventually affect their environmental fate
显示更多 [+] 显示较少 [-]Microplastic appraisal of soil, water, ditch sediment and airborne dust: The case of agricultural systems 全文
2023
Lwanga, Esperanza Huerta | Van Roshum, Ilse | Munhoz, Davi R. | Meng, Ke | Rezaei, Mahrooz | Goossens, Dirk | Bijsterbosch, Judith | Alexandre, Nuno | Oosterwijk, Julia | Krol, Maarten | Peters, Piet | Geissen, Violette | Ritsema, Coen
Although microplastic pollution jeopardizes both terrestrial and aquatic ecosystems, the movement of plastic particles through terrestrial environments is still poorly understood. Agricultural soils exposed to different managements are important sites of storage and dispersal of microplastics. This study aimed to identify the abundance, distribution, and type of microplastics present in agricultural soils, water, airborne dust, and ditch sediments. Soil health was also assessed using soil macroinvertebrate abundance and diversity. Sixteen fields were evaluated, 6 of which had been exposed to more than 5 years of compost application, 5 were exposed to at least 5 years of plastic mulch use, and 5 were not exposed to any specific management (controls) within the last 5 years. We also evaluated the spread of microplastics from the farms into nearby water bodies and airborne dust. We found 11 types of microplastics in soil, among which Light Density Polyethylene (LDPE) and Light Density Polyethylene covered with pro-oxidant additives (PAC) were the most abundant. The highest concentrations of plastics were found in soils exposed to plastic mulch management (128.7 ± 320 MPs.g-1 soil and 224.84 ± 488 MPs.g-1 soil, respectively) and the particles measured from 50 to 150 μm. Nine types of microplastics were found in water, with the highest concentrations observed in systems exposed to compost. Farms applying compost had higher LDPE and PAC concentrations in ditch sediments as compared to control and mulch systems; a significant correlation between soil polypropylene (PP) microplastics with ditch sediment microplastics (r2 0.7 p 0.05) was found. LDPE, PAC, PE (Polyethylene), and PP were the most abundant microplastics in airborne dust. Soil invertebrates were scarce in the systems using plastic mulch. A cocktail of microplastics was found in all assessed matrices.
显示更多 [+] 显示较少 [-]On the probability of ecological risks from microplastics in the Laurentian Great lakes 全文
2023
Koelmans, A.A. | Redondo Hasselerharm, P.E. | Mohamed Nor, N.H. | Gouin, T.
The Laurentian Great Lakes represent important and iconic ecosystems. Microplastic pollution has become a major problem among other anthropogenic stressors in these lakes. There is a need for policy development, however, assessing the risks of microplastics is complicated due to the uncertainty and poor quality of the data and incompatibility of exposure and effect data for microplastics with different properties. Here we provide a prospective probabilistic risk assessment for Great Lakes sediments and surface waters that corrects for the misalignment between exposure and effect data, accounts for variability due to sample volume when using trawl samples, for the random spatiotemporal variability of exposure data, for uncertainty in data quality (QA/QC), in the slope of the power law used to rescale the data, and in the HC5 threshold effect concentration obtained from Species Sensitivity Distributions (SSDs). We rank the lakes in order of the increasing likelihood of risks from microplastics, for pelagic and benthic exposures. A lake-wide risk, i.e. where each location exceeds the risk limit, is not found for any of the lakes. However, the probability of a risk from food dilution occurring in parts of the lakes is 13–15% of the benthic exposures in Lakes Erie and Huron, and 8.3–10.3% of the pelagic exposures in Lake Michigan, Lake Huron, Lake Superior, and Lake Erie, and 24% of the pelagic exposures in Lake Ontario. To reduce the identified uncertainties, we recommend that future research focuses on characterizing and quantifying environmentally relevant microplastic (ERMP) over a wider size range (ideally 1–5000 μm) so that probability density functions (PDFs) can be better calibrated for different habitats. Toxicity effect testing should use a similarly wide range of sizes and other ERMP characteristics so that complex data alignments can be minimized and assumptions regarding ecologically relevant dose metrics (ERMs) can be validated.
显示更多 [+] 显示较少 [-]Integument colour change : Tracking delayed growth of Oppia nitens as a sub-lethal indicator of soil toxicity 全文
2023
Jegede, Olukayode O. | Fajana, Hamzat O. | Adedokun, Adedamola | Najafian, Keyhan | Lingling, Jin | Stavness, Ian | Siciliano, Steven D.
Growth is an important toxicity end-point in ecotoxicology but is rarely used in soil ecotoxicological studies. Here, we assessed the growth change of Oppia nitens when exposed to reference and heavy metal toxicants. To assess mite growth, we developed an image analysis methodology to measure colour spectrum changes of the mite integument at the final developmental stage, as a proxy for growth change. We linked the values of red, green, blue, key-black, and light colour of mites to different growth stages. Based on this concept, we assessed the growth change of mites exposed to cadmium, copper, zinc, lead, boric acid, or phenanthrene at sublethal concentrations in LUFA 2.2 soil for 14 days. Sublethal effects were detected after 7 days of exposure. The growth of O. nitens was more sensitive than survival and reproduction when exposed to copper (EC50growth = 1360 mg/kg compared to EC50reproduction = 2896 mg/kg). Mite growth sensitivity was within the same order of magnitude to mite reproduction when exposed to zinc (EC50growth = 1785; EC50reproduction = 1562 mg/kg). At least 25% of sublethal effects of boric acid and phenanthrene were detected in the mites but growth was not impacted when O. nitens were exposed to lead. Consistent with previous studies, cadmium was the most toxic metal to O. nitens. The mite growth pattern was comparable to mite survival and reproduction from previous studies. Mite growth is a sensitive toxicity endpoint, ecologically relevant, fast, easy to detect, and can be assessed in a non-invasive fashion, thereby complimenting existing O. nitens testing protocols.
显示更多 [+] 显示较少 [-]Potential adverse effects of heavy metals in Ahvaz oil field 全文
2023
Sara Abbasi | Ali Afrous
In the present study, the potential adverse effects of heavy metals in the soil of Ahvaz oil field were evaluated. 9 soil samples were collected and chemical digestion was performed. Global standard methods was used to collect samples and measure metals. Heavy metals Ni, Cd, Pb, Zn, Cu were measured. and geochemical indicators were evaluated. Average concentrations of heavy metals in soil samples were Cd 0.16, Pb 16.63, Zn 22.03, Cu 10.39, Ni 62.97 ppm. The igeo index findings demonstrated that the values for the metals Ni, Cd, Pb, Zn, and Cu were at an uncontaminated level. TRI index values of metals were Moderate. EF of Cd and Ni wer moderate. CF index of Pb is considerable and cf of Cd and Ni and Zn were moderate. The results of CD, MCD, PLI indicators showed that heavy metals in the studied soils are at the level of contamination. The amount of this contamination was moderate to considerable. The ecological risk of these metals was considerable.
显示更多 [+] 显示较少 [-]Effects of Fe2o3 and Co2o3 nanoparticles on Organisms in Freshwater 全文
2023
Leila Farsi | Mojgan Khodadadi | Sima Sabzalipour | Nemaat Jaafarzadeh Haghighi Fard | Farid Jamali-Sheini
Nanoparticles (NPs) are causing threats to the environment. In this review, we examined how hematite (Fe2O3) and cobalt oxide (Co2O3) nanoparticles impact the species of freshwater green algae Chlorella vulgaris (C. vulgaris). We exposed laboratory cultures to five initial concentrations of nanoparticles and measured impacts on species in 24, 48, 72, 96, 120, and 144 hours in Karun River water at 20-25°C. Our results indicated that Fe2O3 and Co2O3 NPs significantly (dependent on concentration) reduced the chlorophyll a, b, and carotenoid contents of algae C. vulgaris compared to the control group (P <0.05). Also, due to the combination of these two nanoparticles, Co2O3 (50 Fe2O3 +100 Co2O3) has a more negative effect on algae chlorophyll change. According to the data, the exposure concentration was also found to be a more effective factor in the Chlorophyll content in algae species as compared to the exposure time. Our study suggests this nanoparticle has potential to affect aquatic life and ecosystem properties of freshwater habitats.
显示更多 [+] 显示较少 [-]Occupational exposure limits for 1, 3-butadiene based on carcinogenic effects: a comparison of the threshold and non-threshold approaches 全文
2023
Masoomeh Vahabi Shekarloo | Zahra Moradpour | Marzieh Sadeghian
1, 3-Butadiene (BD) is primarily used for the production of synthetic rubbers and polymers, which are found in many industrial and consumer products. BD is suspected to be both carcinogenic and genotoxic to humans. This study aims to compare occupational exposure limits (OELs) based on BDâs carcinogenic effects using threshold and non-threshold methods in industrial settings. A review of published literature was carried out to find the most suitable in vivo carcinogenic data. Selection criteria included the number of dose levels considering more than three dose level and chronic exposure through the lung route. Studies of the National Toxicology Program (NTP) and Melnick et al. met the criteria for this study. The U.S. Environmental Protection Agency (EPA)âs BMD software, version 3.2.0, was utilized to estimate BMDL10. In the threshold approach, OELs were calculated using BMDL10 divided by uncertainty factors. The margin of exposure (MOE) method was used as a non-threshold approach. In the threshold approach, an OELI of 2.3 ppm and 3.8 ppm was estimated in males and females, respectively. In the non-threshold approach, the OELII of 0.008 ppm and 0.014 ppm was calculated for males and females, respectively, which were substantially lower than those found using the threshold method. Examining and comparing the results of this study to the threshold limit values (TLVs) and carcinogenic risk values determined by the EPA revealed that the threshold values are closer to the safe workplace concentrations (concentrations where no carcinogenic effects have been detected). Consequently, the use of non-threshold approaches results in an inaccurate estimation of carcinogenic risk.
显示更多 [+] 显示较少 [-]Environmental pollution and nutritional quality modulate immune response of the wood mouse (Apodemus sylvaticus) through hormonal disturbances 全文
2023
Devalloir, Quentin | Fritsch, Clémentine | Alchammas, Yara | Raoul, Francis | Driget, Vincent | Amiot, Caroline | Ozaki, Shinji | van den Brink, Nico | Scheifler, Renaud
Cadmium (Cd) and lead (Pb) are known to enhance immune cell damages and to decrease cellular immunity, promoting higher susceptibility to infectious diseases. Selenium (Se) is an essential element involved in immunity and reactive oxygen species scavenging. This study aimed at evaluating how Cd and Pb and low nutritional (Se) quality modulate immune response to a bacterial lipopolysaccharide (LPS) challenge in wood mice (Apodemus sylvaticus). Mice were trapped near a former smelter in northern France in sites of High or Low contamination. Individuals were challenged immediately after capture or after five days of captivity, fed a standard or a Se-deficient diet. Immune response was measured with leukocyte count and plasma concentration of TNF-α, a pro-inflammatory cytokine. Faecal and plasma corticosterone (CORT), a stress-hormone involved in anti-inflammatory processes, was measured to assess potential endocrine mechanisms. Higher hepatic Se and lower faecal CORT were measured in free-ranging wood mice from High site. LPS-challenged individuals from High site showed steeper decrease of circulating leukocytes of all types, higher TNF-α concentrations, and a significant increase of CORT, compared to individuals from Low site. Challenged captive animals fed standard food exhibited similar patterns (decrease of leukocytes, increase of CORT, and detectable levels of TNF-α), with individuals from lowly contaminated site having higher immune responses than their counterparts from highly polluted site. Animals fed Se-deficient food exhibited lymphocytes decrease, no CORT variation, and average levels of TNF-α. These results suggest (i) a higher inflammatory response to immune challenge in free-ranging animals highly exposed to Cd and Pb, (ii) a faster recovery of inflammatory response in animals lowly exposed to pollution when fed standard food than more exposed individuals, and (iii) a functional role of Se in the inflammatory response. The role of Se and mechanisms underlying the relationship between glucocorticoid and cytokine remain to be elucidated.
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