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Argyrophilic nucleolar organizer regions in oral mucosa cells of crack and cocaine users: a cross-sectional study Full text
2020
Góes Rabelo, Rosângela | Salgueiro, Arthur Pias | Visioli, Fernanda | da Silva, Viviane Palmeira | das Graças Alonso Oliveira, Maria | Ribeiro, Daniel Araki | Cury, Patricia Ramos | dos Santos, Jean Nunes
The objective of this study was to analyze and compare the presence of argyrophilic nucleolar organizer regions (AgNORs) in exfoliated cells obtained from the buccal mucosa among crack and cocaine users and non-users by the AgNOR staining technique. Seventy-three males ≥ 18 years were categorized into two groups: 38 crack and/or cocaine users and 35 non-user volunteers. They were interviewed and responded a questionnaire regarding general health and drug addiction. Exfoliative cytology specimens were collected from the clinically intact buccal mucosa, and cytological preparations were fixed and stained by AgNOR technique. The mean number of AgNORs (p = 0.02) and the percentage of epithelial cells with more than 3 (p = 0.01) and 4 (p = 0.04) AgNORs/nucleus were significantly higher in the non-user group. In conclusion, the frequency and diversity of substances present in the drugs—cocaine, crack, and alcohol—consumed by the volunteers of this study may have influenced the number of AgNORs and the response to damage and consequent effect on protein synthesis.
Show more [+] Less [-]Biological activity and safety profile of monoterpenes against Plutella xylostella L. (Lepidoptera: Plutellidae) Full text
2020
Cai, Yuehong | Hu, Xian | Wang, Pan | Xie, Yongjian | Lin, Zhufeng | Zhang, Zhilin
Plutella xylostella L. is a cosmopolitan pest of wild and cultivated crucifer vegetables worldwide. It has developed resistance to almost all commercial chemicals, making them one of the most problematic field pests in China. The natural plant extracts and essential oils (EOs) could be a safe alternative for agricultural pests. The development and production of EOs decrease the negative effects of synthetic chemicals. In the present study, the fumigation activity of 8 pure monoterpenes against P. xylostella was evaluated. Results from fumigation tests revealed that 8 tested compounds exhibited various degrees of toxicity against adults of the diamondback moth. Cuminaldehyde was the most toxic compound based on the 12-h LC₅₀ (0.17 mg/L) and 24-h LC₅₀ (0.12 mg/L) values, respectively. Also for larvae and eggs, cuminaldehyde was the most toxic compound. The 12-h LC₅₀ value for cuminaldehyde to 1st, 2nd, and 3rd instar larvae was 0.10 mg/L, 0.12 mg/L, and 0.55 mg/L, respectively. The 24-h LC₅₀ value for the different instar larvae was 0.07 mg/L, 0.09 mg/L, and 0.35 mg/L, respectively. The 24-h LC₅₀ value for eggs (endpoint hatching rate) was 1.95 mg/L for cuminaldehyde, followed by carvacrol and eugenol (2.05 mg/L and 2.31 mg/L, respectively). Cuminaldehyde was very friendly to the larvae and adults of Harmonia axyridis and did not cause any mortality. Our results indicated that cuminaldehyde had potential insecticidal activity against P. xylostella and could be utilized in the novel biological pesticide development.
Show more [+] Less [-]Urinary paraben concentrations and their implications for human exposure in Iranian pregnant women Full text
2020
Hajizadeh, Yaghoub | Kiani Feizabadi, Ghasem | Ebrahimpour, Karim | Shoshtari-Yeganeh, Bahareh | Fadaei, Saeid | Darvishmotevalli, Mohammad | Karimi, Hossein
Parabens are widely used as preservatives in cosmetics, medicines, and foods due to its antimicrobial properties. Concerns have been raised regarding the estrogenic activity and potential endocrine disruption effects of parabens. Studies on monitoring of paraben exposure in the Iranian population are very scarce. This study was carried out to measure urinary concentrations of parabens, to estimate their daily intake, and to identify some of the sociodemographic factors affecting exposure to these compounds. The concentrations of methylparaben (MP), ethylparaben (EP), propylparaben (PP), and butylparaben (BP) were measured in urine samples collected from 95 Iranian pregnant women by gas chromatography mass spectrometry. The highest median concentration was 87.0 μg/L for MP, followed by PP, EP, and BP with median concentrations of 15.6, 9.64, and 8.57 μg/L, respectively. Except BP, the urinary concentrations of other parabens were comparable to those in other countries. Also, the highest daily intake was related to MP (median = 16.5 μg/kg-BW/day), which is less than the acceptable daily intake (ADI). A significant positive correlation was observed between the measured parabens. Significant negative associations were observed between age and BP, BMI and EP as well as parity and PP. On the other hand, income and smoking were significantly positively associated with MP, BP and EP, BP, respectively. The urinary MP and BP concentrations were higher among the subjects with diploma education (P = 0.003 and P = 0.006, respectively), and during the spring, urinary MP concentration was higher than other seasons. The results showed that Iranian pregnant women are more prone to parabens and their urinary paraben concentrations are associated with sociodemographic factors. This result could serve as a basis for evaluating the rate of exposure of the Iranian population to parabens in future studies.
Show more [+] Less [-]Stakeholders’ perspective on strategies to promote contaminated site remediation and brownfield redevelopment in developing countries: empirical evidence from Pakistan Full text
2020
Ahmad, Naveed | Zhu, Yuming | Shao, Jing | Lin, Hongli
Due to the potential of reducing negative outcomes of brownfields on environment and contribution to urban sustainability, brownfield redevelopment (BR) gained considerable recognition in the more recent era. Comprehensive literature shows that many studies proposed strategies to promote BR in developed nations; however, studies focusing on developing economies are scarce. Therefore, this study intends to identify significant strategies to promote BR in developing countries by taking the case of Pakistan. A comprehensive literature review and expert opinion were commenced to identify potential strategies. Data were collected from the main stakeholders involved in BR process through an empirical questionnaire. The findings revealed that “Low-interest loans and subsidies with the collaboration of government and financial institutions,” “Standardized definition, guidelines, and simplified brownfield process,” “Development of technical and infrastructure support,” “Create investors interest,” “Strengthening remediation technologies R&D” were the five most important strategies to promote BR in Pakistan. Theoretically, the novelty of the current study is to highlight the key strategies to promote BR in developing countries. Practically, the study facilitates governments, urban policymakers, environmentalists, and stakeholders to propose and implement appropriate strategies for promoting BR. Future studies can consider modeling the interactions between strategies and their impact on BR adoption.
Show more [+] Less [-]Year-to-year climate variability affects methane emission from paddy fields under irrigated conditions Full text
2020
Sun, Huifeng | Zhou, Sheng | Zhang, Jining | Zhang, Xianxian | Wang, Cong
A field experiment in Yangtze River delta of China was conducted to investigate the effects of four treatments (conventional chemical fertilizers (CF), chemical fertilizers incorporated with wheat straw (CF-WS), slow-release urea fertilizer incorporated with wheat straw (SCF-WS), and no fertilizers (Non-F)) on methane emission, rice grain yield, and straw biomass in three (2013, 2014, and 2015) consecutive growing seasons. Similar air temperature and precipitation were recorded in 2014 and 2015 normal seasons; however, the 2013 season with a 2.1–2.3 °C higher mean air temperature and a 61–64% lower precipitation than the normal seasons was considered as a warm-and-dry season.No significant differences in seasonal total methane emissions across all treatments were observed in 2014 and 2015 seasons. Seasonal total methane emissions were 58–294% higher in 2013 season compared to 2014 and 2015 seasons, which suggests that higher ambient temperatures increase methane emissions from paddy fields. The enhanced methane emission was seen mainly during the mid-to-late growth stages after mid-season drainage. CF-WS and SCF-WS significantly increased methane emissions before mid-season drainage relative to CF, and thereby enhanced methane emissions in both normal and warm-and-dry seasons in a seasonal scale.While rice grain yield in each treatment in 2013 season was close to or lower than that in 2014 and 2015 seasons, straw biomass in CF, CF-WS, and SCF-WS in 2013 season were significantly higher than those in 2014 and 2015 seasons, by both 29%, 33–41%, and 15–16%, respectively. Enhancements in methane emissions at higher air temperatures were significantly correlated to its greater straw biomass. Furthermore, combination of slow-release urea fertilizer and straw by ploughing can significantly increase above-ground biomass yields and nitrogen use efficiency in both normal and warm-and-dry seasons.
Show more [+] Less [-]The effect of environmental regulation on capacity utilization in China’s manufacturing industry Full text
2020
Cheng, Zhonghua | Liu, Jun | Li, Lianshui | Gu, Xinbei
How environmental regulations are used to improve manufacturing capacity is crucial to the future development of China’s manufacturing industry from a quality point of view. This paper adopts a dynamic spatial panel model to empirically analyze both the effects of different types of environmental regulation policies on capacity utilization in China’s manufacturing industry and their mechanisms. The results show that China’s manufacturing capacity utilization varies a great deal, with improvements in technical efficiency playing the main role, although with significant regional differences. Both command-and-control and market-incentive environmental regulation are conducive to improvements in manufacturing capacity utilization; market-incentive environmental regulation, however, plays the stronger role. The above mechanisms have certain differences though. Both types of environmental regulations are able to improve manufacturing capacity utilization by improving technical efficiency and equipment utilization but the command-and-control policy tool exerts a greater effect in improving technical efficiency while the market-incentive mechanism has a greater effect in improving equipment utilization.
Show more [+] Less [-]Performance evaluation of conventional and hybrid woven fabrics for the development of sustainable personal protective clothing Full text
2020
Memon, Arshad Hussain | Peerzada, Mazhar Hussain | Brohi, Khan Muhammad | Memon, Sheeraz Ahmed | Mangi, Sajjad Ali
This study examines the performance level of hybrid woven protective clothing (HWPC), manufactured from Kevlar® (K) and Ramie (R) yarns. The weave structures (plain, twill 1/3) and variables fiber ratios were used to produce HWPC. The performance level of HWPC was measured according to EN 388:2016. We came to the conclusion that blade cut resistance of plain and twill structure sustained protection level up to increase of KR 80:20 and KR 70:30, respectively; puncture resistance of K100% and HWPC remained in the same level of protection for plain and twill weaves; Abrasion resistance of K100% and HWPC of plain and twill weaves samples presented abrasive performance of same protection level, but the average number of cycles sustained for twill weave samples was slightly higher than plain weave. However, comparing the plain and twill weaves sample for tear resistance, twill weave samples have higher tear resistance than plain weave. A gray relational analysis and Taguchi method was performed to optimize the performance of two structures with variable fiber ratios. It was established that the article produced with K&R yarns with KR 80:20 ratio and twill weave presented the best performance against all test runs. The main objective of this study is to reduce plastic pollution by reducing the amount of synthetic fiber proportion in personal protective clothing and thereby reducing the dependence on nonrenewable sources for synthetic fiber. The 41 g/m² reduction of Kevlar® fiber has been made in a conventional PC with ramie fiber, without compromising the protection level. This will enhance the sustainability of HWPC.
Show more [+] Less [-]Interactions between heavy metals and other mineral elements from soil to medicinal plant Fengdan (Paeonia ostii) in a copper mining area, China Full text
2020
Shen, Zhangjun | Chen, Yansong | Xu, Decong | Li, Lingling | Zhu, Yong
In order to analyze the interaction relationship between heavy metals and other mineral elements during the processes of absorption and translocation by plant grown on heavy metal–contaminated area, the concentrations of Cu, Zn, Mn, Cd, Pb, Ca, Mg, Fe, and K in the medicinal plant Paeonia ostii T. Hong et J. X. Zhang and its rhizospheric soil were determined, which grow around an abandoned copper tailings reservoir in Tongling City, China. Geo-accumulation index (Igₑₒ) calculation indicated that Cu and Pb are the main pollution elements in the rhizospheric soil. Moreover, the Cu and Pb concentrations in the cortex moutan of P. ostii exceeded the maximum permissible limits for food product safety. The bioaccumulation factor values of the tested metals in plant roots were found < 0.50, with the exception of Ca (maximum 5.99). The translocation factor values of detected heavy metals Cd and Pb were more than 1.00, which indicated that P. ostii could be considered a potential accumulator plant for Cd and Pb. Significant positive correlations including Cu-Cd, Cu-Zn, Cu-Pb, Cd-Zn, Cd-Fe, Cd-Fe, Zn-Pb, Pb-Fe, Mn-Fe, and Ca-Mg in the cortex moutan and Cu-Zn, Cu-Fe, Zn-Mg, Zn-Fe, and Mn-K in the leaves were observed (P < 0.05). Significant positive correlation between Cu, Zn, Mg, and Fe was also confirmed in the processes of absorption and translocation from the soil to plant (P < 0.05), which evidenced that synergistic element interactions of the essential elements Cu, Zn, Mg, and Fe are a result of the similarity in their ionic radii and octahedral coordination geometry.
Show more [+] Less [-]Assessment of phytostabilization potential of two Salix L. clones based on the effects of heavy metals on the root anatomical traits Full text
2020
Hrkić Ilić, Zorana | Pajević, Slobodanka | Borišev, Milan | Luković, Jadranka
Willow species (Salix L.) are a useful tool for assessing phytostabilization of the sites polluted by heavy metals. Phytostabilization potential of two willow genotypes (Salix alba L. clone ‘68/53/1’ and Salix nigra Marshall clone ‘0408’) has been evaluated in a 45-day hydroponic experiment, using stem cuttings (diameter 12 to 14 mm, length 20 cm) exposed to two concentrations (10⁻⁴ M and 10⁻⁵ M) of individually applied Cd, Ni, and Pb. Metals were diluted in 25% Hoagland’s solution, in forms of CdCl₂·H₂O, NiSO₄·6H₂O, and Pb-EDTA. The control group of cuttings was grown in 25% Hoagland’s solution without heavy metals. High Cd concentrations in willow roots, 8637 mg/kg (clone ‘68/53/1’) and 6728 mg/kg of dry weight (clone ‘0408’), have indicated a high phytostabilization potential. However, detailed analyses of cross-sectional area of the root cortex and the central cylinder revealed that the excess concentration of Cd led to a significant reduction of measured anatomical rootʼs traits of clone ‘68/53/1’ in comparison with the control samples. Excessive concentration of Ni and Pb in nutrient solution increased the values of quantitatively measured rootʼs traits of clone ‘0408’, implying stimulatory effects of the applied concentrations. Concentration of 10⁻⁴ M of each metal had more negative effects on the rootsʼ anatomical traits, notably on parenchymal and exodermal cells and vessels. Deposits of metals were observed in root tissues. Clone ‘0408’ demonstrated an increased tolerance to heavy metals, which could potentially make this clone useful in phytostabilization.
Show more [+] Less [-]Copper removal from wastewater by a chitosan-based biodegradable composite Full text
2020
Velasco-Garduño, Oscar | Martinez, Manuel E. | Gimeno, Miquel | Tecante, Alberto | Beristain-Cardoso, Ricardo | Shirai, Keiko
This work demonstrates that a biodegradable chitosan-based biocomposite packed in mini-reactors successfully removes copper ions from aqueous solutions. The chitosan is obtained by deacetylation of biological chitin, which is extracted from shrimp wastes by lactic acid fermentation. The polysaccharide is embedded in a biodegradable prepolymer matrix before extrusion to produce porous cylindrical pellets of 2 × 80 mm. The highest copper ion removal is 62.5 mg Cu²⁺ per g of the biodegradable adsorbent. Additionally, the adsorption capacity of the material, below its saturation, allows several cycles of reuse with a hydraulic retention time reduction of 1 h. This chitosan-based material is advantageous when compared with other approaches using non-biodegradable materials or costly commercial adsorbents for removing heavy metal ions in wastewater effluents as well as a filter component in water purification devices.
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