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Effects of increasing temperature due to aquatic climate change on the self-fertility and the sexual development of the hermaphrodite fish, Kryptolebias marmoratus Полный текст
2017
Park, Chang-Beom | Kim, Yŏng-jun | Soyano, Kiyoshi
In order to assess the effects of increasing temperature on the reproductive performance of fish, different thermal conditions (i.e., 25.0, 26.5, 27.5, 28.5, 30.0 °C) were used in this study and the self-fertilizing hermaphrodite fish, Kryptolebias marmoratus, was exposed to these different thermal conditions. During an exposure period of 30 to 150 days, the gonadosomatic index (GSI), gonadal development, the levels of plasma 17β-estradial (E2) and testosterone (T), hepatic vitellogenin (VTG) mRNA abundance, and the number of self-fertilized eggs were analyzed. This study confirmed that a high water temperature above 27.5 °C led to the suppression of self-fertility of hermaphroditic fish from 30 days after exposure. The oocyte quality and maturation would be affected by the disruption of hepatic VTG synthesis at a high water temperature of 30 °C, which resulted in the reduced the self-fertility in K. marmoratus. Consequently, this study suggests that elevated water temperature due to aquatic climate change prior to sexual maturation and the onset of spawning can lead to the reproductive dysfunction of hermaphroditic K. marmoratus.
Показать больше [+] Меньше [-]Effects of co-composting of farm manure and biochar on plant growth and carbon mineralization in an alkaline soil Полный текст
2017
Qayyum, Muhammad Farooq | Liaquat, Fatima | Rehman, Rabia Abdur | Gul, Mehreen | ul Hye, Muhammad Zafar | Rizwan, Muhammad | Rehaman, Muhammad Zia ur
In the present study, the effects of co-composts of biochar (BC) and farm manure (FM) on the growth of wheat (Triticum aestivum L.) and carbon mineralization in an alkaline soil were investigated. The co-composts of FM and BC were prepared at various ratios (FM₁₀₀:BC₀, FM₇₅:BC₂₅, FM₅₀:BC₅₀, FM₂₅:BC₇₅, FM₀:BC₁₀₀) using aboveground piles and were used in two separate experiments conducted simultaneously. In the plant growth trial, prepared co-composts were applied at a rate of 2% w/w and wheat was grown at two fertilizer levels (half and full) until maturity. In the incubation experiment, same treatments were used and carbon mineralization was studied over a period of 79 days. The priming effect and net CO₂ efflux were calculated using CO₂ release data. Analysis of postincubation soil showed no significant effect of treatments on the pH of soil. However, electrical conductivity and organic matter were significantly influenced by all treatments. The increasing BC ratio in the compost reduced the carbon mineralization in soil in a dose-additive manner. Increase in BC proportion in composts (FM₅₀:BC₅₀, FM₂₅:BC₇₅, FM₀:BC₁₀₀) stabilized the native carbon of the soil and caused negative priming effect (−1.9, −5.6, and −8.48%, respectively). Regarding plant growth, the results showed an enhancement in the grain yield with the application of compost than control. Total nitrogen (N), phosphorus, and potassium (K) contents of the soil were also increased by the application of compost than control (un-amended soil). Significantly higher N and K concentrations in wheat plants were also examined when soil was treated with compost than control. The use of compost with half fertilizer was better in increasing grain yield, especially with higher BC proportion in the compost than FM.
Показать больше [+] Меньше [-]Simultaneous oxidation of ammonium and cresol isomers in a sequencing batch reactor: physiological and kinetic study Полный текст
2017
Salas-Cortés, Juan Antonio | Cuervo-López, Flor de María | Texier, Anne-Claire
The aim of this study was to evaluate the physiological and kinetic capacities of a nitrifying consortium to simultaneously oxidize ammonium (138 mg N/L day), m-cresol, o-cresol, and p-cresol (180 mg C/L day in mixture) in a sequencing batch reactor (SBR). A 1-L SBR was firstly operated without cresol addition (phase I) for stabilizing the nitrification respiratory process with ammonium consumption efficiencies close to 100 % and obtaining nitrate as the main end product. When cresols were added (phase II m-cresol (10, 20, and 30 mg C/L); phase III m-cresol (30 mg C/L) and o-cresol (10, 20, and 30 mg C/L); phase IV a mixture of three isomers (30 mg C/L each one)), inhibitory effects were evidenced by decreased values of the specific rates of nitrification compared with values from phase I. However, the inhibition diminished throughout the operation cycles, and the overall nitrifying physiological activity of the sludge was not altered in terms of efficiency and nitrate yield. The different cresols were totally consumed, being o-cresol the most recalcitrant. The use of SBR allowed a metabolic adaptation of the consortium to oxidize the cresols as the specific rates of consumption increased throughout the cycles, showing that this type of reactor can be a good alternative for treating industrial effluents in a unique reactor.
Показать больше [+] Меньше [-]Identifying effective factors on consumers’ choice behavior toward green products: the case of Tehran, the capital of Iran Полный текст
2017
Rahnama, Hassan | Rajabpour, Shayan
The environment is increasingly turning to a vital and very important issue for all people. By increasing environmental concerns as well as legislating and regulating rules on the protection of the environment and the emergence of green consumers, implementing green marketing approach for organizations seems to be more crucial and essential. As a result, the need for ecological products and green business activities compels companies to combine environmental issues with marketing strategies. The first step in the success of companies and organizations is to identify consumers and their consumption behaviors correctly and accurately. So, the purpose of this study is to identify effective factors for the choice of consumers of green products. We used consumption values (functional value, social value, emotional value, conditional value, epistemic value, and environmental value) as the effective factor for choosing green products. The original place of this research was in Tehran, capital city of Iran, which is one of the most polluted cities in the world due to environmental issues. The results from the survey questionnaires are analyzed using confirmatory factor analysis and structural equation modelling. The results indicated that functional value-price, functional value-quality, social value, epistemic value, and environmental value had significantly positive effects on the choice of green products; also, conditional value and emotional value had no influence on it. It was concluded that the main influential factors for consumers’ choice behavior regarding green products included environmental value and epistemic value. This study emphasized the proper pricing of green products by producers and sellers.
Показать больше [+] Меньше [-]Periodontal status in crack and cocaine addicted men: a cross-sectional study Полный текст
2017
Cury, Patricia Ramos | Oliveira, Maria Graças Alonso | dos Santos, Jean Nunes
This cross-sectional study evaluated the association between crack/cocaine addiction and periodontal disease in men. Periodontal examination (probing depth, clinical attachment level, bleeding on probing, and plaque index) and interviews were performed in 160 patients (≥18 years) from the Federal University of Bahia. Crack and cocaine dependence was defined according to the medical records and interviews of each patient; all drug addicted volunteers used both crack and cocaine. T test, Chi-square test, and logistic regression were used to assess the associations between destructive periodontal disease and crack/cocaine dependence (p ≤ 0.05). Probing depth was significantly greater in crack/cocaine addicted individuals (2.84 ± 0.76 mm) compared with non-addicted individuals (2.55 ± 0.73 mm, p = 0.04). After adjusting for covariates, periodontitis was not significantly associated with crack/cocaine addiction (OR = 2.31, 95 % CI = 0.82–6.46, p = 0.11), which was only associated with age ≥35 years (OR = 4.16, 95 % CI = 1.65–10.50, p = 0.003) and higher dental plaque index (OR = 6.46, 95 % CI = 1.95–21.42, p = 0.002). In conclusion, although probing depth was greater in crack/cocaine addicted individuals, destructive periodontal disease was not associated with crack and cocaine addiction in the present population. Destructive periodontal disease was associated with age and dental plaque. Further studies in a larger sample size are required to confirm the results.
Показать больше [+] Меньше [-]Synergetic effect of rhamnolipid from Pseudomonas aeruginosa C1501 and phytotoxic metabolite from Lasiodiplodia pseudotheobromae C1136 on Amaranthus hybridus L. and Echinochloa crus-galli weeds Полный текст
2017
Adetunji, Charles | Oloke, Julius | Anil Kumar, | Swaranjit, Singh | Akpor, Benjamin
Rhamnolipid (Rh) is a biosurfactant produced by the bacterial Pseudomonas aeruginosa. This present study investigates rhizospheric strain C1501 of P. aeruginosa with an accession number KF976394 with the best production of rhamnolipid: a biosurfactant. The partially purified rhamnolipid from strain C1501 and Tween 80 was tested on mycelial growth of wild strain C1136. The enzyme activities involved in biodegradation, as well as necrosis induction on the tested weeds, were performed using scanning electron microscopy. It was observed that the different concentrations of rhamnolipid tested enhanced the dry mycelia weight yield of Lasiodiplodia pseudotheobromae which has been established to be producing a phytotoxic metabolite for killing weeds. It was observed that strain C1136 had a high level of cellulase and xylanase enzyme activities during this study. The scanning electron microscopy showed that the mutant strain of C1136 combined with 0.003% v/v of rhamnolipid enhances biodegradability and a high level of necrosis on the tested weeds compared with that on the untreated weeds. The highest CMCase activities and xylanase activities were obtained on the fourth day from the phytotoxic metabolite produced from the mutant strain of L. pseudotheobromae when combined with 0.003% v/v of rhamnolipid. This study has shown that rhamnolipid can serve as an adjuvant in order to enhance the penetrability of bioherbicide active ingredient for controlling weeds.
Показать больше [+] Меньше [-]Response of spontaneous plants from an ex-mining site of Elba island (Tuscany, Italy) to metal(loid) contamination Полный текст
2017
Pistelli, Laura | D’Angiolillo, Francesca | Morelli, Elisabetta | Basso, Barbara | Rosellini, Irene | Posarelli, Mauro | Barbafieri, Meri
The release of large amounts of toxic metals in the neighboring sites of abandoned mine areas represents an important environmental risk for the ecosystem, because it adversely affects soil, water, and plant growth. The aim of the present study was to investigate the metal(loid) (As, Cr, Cu, Ni, Pb, and Zn) contents of native Mediterranean plants grown on the ex-mining area of Elba island (Italy), with the prospective of its recovery by further phytoremediation technology. Soil samples were collected and characterized for metal(loid) content in total and potentially available (EDTA-extractable) fractions. Arsenic was particularly high, being 338 and 2.1 mg kg⁻¹ as total and available fractions, respectively. Predominant native species, namely Dittrichia viscosa L. Greuter, Cistus salviifolius L., Lavandula stoechas L., and Bituminaria bituminosa L., were analyzed for metal content in the different plant organs. D. viscosa exhibited the highest metal(loid) content in the leaves and the singular behavior of translocating arsenic to the leaves (transfer factor about 2.06 and mean bioconcentration factor about 12.48). To assess the healthy status of D. viscosa plants, the leaves were investigated further. The activities of the main antioxidant enzymes and the levels of secondary metabolites linked to oxidative stress in plants from the ex-mining area were not significantly different from those of control plants, except for a lower content of carotenoids, indicating that native plants were adapted to grow in these polluted soils. These results indicate that D. viscosa can be suitable for the revegetation of highly metal-contaminated areas.
Показать больше [+] Меньше [-]Removal of phenanthrene in contaminated soil by combination of alfalfa, white-rot fungus, and earthworms Полный текст
2017
Deng, Shuguang | Zeng, Defang
The aim of this study was to investigate the removal of phenanthrene by combination of alfalfa, white-rot fungus, and earthworms in soil. A 60-day experiment was conducted. Inoculation with earthworms and/or white-rot fungus increased alfalfa biomass and phenanthrene accumulation in alfalfa. However, inoculations of alfalfa and white-rot fungus can significantly decrease the accumulation of phenanthrene in earthworms. The removal rates for phenanthrene in soil were 33, 48, 66, 74, 85, and 93% under treatments control, only earthworms, only alfalfa, earthworms + alfalfa, alfalfa + white-rot fungus, and alfalfa + earthworms + white-rot fungus, respectively. The present study demonstrated that the combination of alfalfa, earthworms, and white-rot fungus is an effective way to remove phenanthrene in the soil. The removal is mainly via stimulating both microbial development and soil enzyme activity.
Показать больше [+] Меньше [-]miRNA-based heavy metal homeostasis and plant growth Полный текст
2017
Noman, Ali | Aqeel, Muhammad
Plants have been naturally gifted with mechanisms to adjust under very high or low nutrient concentrations. Heavy metal toxicity is considered as a major growth and yield-limiting factor for plants. This stress includes essential as well as non-essential metals. MicroRNAs (miRNAs) are known for mediating post-transcriptional regulation by cleaving transcripts or translational inhibition. It is commonly agreed that an extensive understanding of plant miRNAs will significantly help in the induction of tolerance against environmental stresses. With the introduction of the latest technology like next generation sequencing (NGS), a growing figure of miRNAs has been productively recognized in several plants for their diverse roles. These miRNAs are well-known modulators of plant responses to heavy metal (HM) stress. Data regarding metal-responsive miRNAs point out the vital role of plant miRNAs in supplementing metal detoxification by means of transcription factors (TF) or gene regulation. Acting as systemic signals, miRNAs also synchronize different physiological processes for plant responses to metal toxicities. In contrast to practicing techniques, using miRNA is a greatly helpful, pragmatic, and feasible approach. The earlier findings point towards miRNAs as a prospective target to engineer heavy metal tolerance in plants. Therefore, there is a need to augment our knowledge about the orchestrated functions of miRNAs during HM stress. We reviewed the deterministic significance of plant miRNAs in heavy metal tolerance and their role in mediating plant responses to HM toxicities. This review also summarized the topical developments by identification and validation of different metal stress-responsive miRNAs.
Показать больше [+] Меньше [-]Beneficial effects of quercetin on titanium dioxide nanoparticles induced spermatogenesis defects in mice Полный текст
2017
Khorsandi, Layasadat | Orazizadeh, Mahmoud | Moradi-Gharibvand, Nahid | Hemadi, Masoud | Mansouri, Esrafil
Many recent studies have demonstrated that most nanoparticles (NPs) have an adverse or toxic action on male germ cells. In present study, protective effect of quercetin (Que) on titanium dioxide nanoparticle (NTiO₂)-induced spermatogenesis defects in mice was investigated. Thirty-two Naval Medical Research Institute (NMRI) mice were randomly divided into four groups. Que group received 75 mg/kg of Que for 42 days. NTiO₂ group received 300 mg/kg NTiO₂ for 35 days. NTiO₂ + Que group initially received 75 mg/kg Que for 7 days and was followed by concomitant administration of 300 mg/kg NTiO₂ for 35 days. Control group received only normal saline for 42 days. Sperm parameters, testosterone concentration, histological criteria, and apoptotic index were assessed. Product of lipid peroxidation (MDA), superoxide dismutase (SOD), and catalase (CAT) activities were also evaluated for oxidative stress in testicular tissue. Administration of NTiO₂ significantly induced histological changes in testicular tissue; increased apoptotic index; and decreased testicular weight, testosterone concentration, and sperm quality (p < 0.01). In the testis, NTiO₂ increased oxidative stress through an increase in lipid peroxidation and a decrease in SOD and CAT activities (p < 0.05). Que pretreatment could significantly attenuate testicular weight; apoptotic index; and histological criteria including vacuolization, detachment, and sloughing of germ cells in seminiferous tubules. Serum and tissue testosterone levels were significantly increased in Que-pretreated mice (p < 0.01). Sperm parameters including sperm number, motility, and percentage of abnormality were also effectively improved by Que pretreatment (p < 0.01). Pretreatment of Que significantly ameliorated oxidative stress and increased the activities of SOD and CAT in testicular tissue. These results indicate that sperm production can be increased by Que pretreatment in NTiO₂-intoxicated mice. The improved sperm quality and reverse testis histology by Que pretreatment may be a consequence of elevation testosterone concentration, reduction in germ cell apoptosis, and suppression of oxidative stress in testicular tissue.
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