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Going the Distance: Influence of Distance Between Boat Noise and Nest Site on the Behavior of Paternal Smallmouth Bass Full text
2020
MacLean, K. | Prystay, T. S. | Lawrence, M. J. | Zolderdo, A. J. | Gutowsky, L. F. G. | Staaterman, E. | Gallagher, A. J. | Cooke, S. J.
The effects of anthropogenic noise have garnered significant attention in marine ecosystems, but comparatively less is known about its impacts on freshwater ecosystems. For fish that provide parental care, the effects of acoustic disturbance could have fitness-level consequences if nest tending behavior is altered. This study explored the effects of motorboat noise on the parental behavior of nesting male smallmouth bass (Micropterus dolomieu; Lacépède, 1802), an important freshwater game fish in North America that provides sole paternal care to offspring. Specifically, we evaluated how boat noise proximity to a bass nest (ranging from 4.5 to 90 m) influenced paternal care behaviors. A total of 73 fish were exposed to a 3-min motorboat playback designed to simulate a boat sound that typically occurs in areas near littoral nesting sites. The fish were video recorded, and their behaviors were analyzed before, during, and after exposure to the playback. Residency time was the only behavioral metric to be adversely affected by noise playbacks but only when in close proximity to the speaker. Our results suggest that boat noise may have an impact on bass reproductive fitness in specific contexts where combustion motors are used near shore during the nesting period. The largely null findings may indicate a resilience to boat noise and/or habituation to the noise. In addition, boats displace water and create waves that represent another form of disturbance that could be experienced by fish but was not simulated here. Future research should integrate behavioral and physiological responses to boat noise and other aspects of boat disturbance to better understand the fitness impacts of boating activity on freshwater fish.
Show more [+] Less [-]First Investigations on the Removal of Tungsten Species from Water Using Multi-walled Carbon Nanotubes Full text
2020
Ihsanullah, Ihsanullah | Sājid, Muḥammad | Kabeer, Muhamed | Shemsi, Ahsan Mushir | Atieh, Muataz Ali
A first study on the adsorptive removal of tungsten species from the aqueous phase by using the multi-walled carbon nanotubes (MWCNTs) is reported. The MWCNTs were employed for the uptake of tungsten species at pH 6 in batch experiments. It was observed that 100% of tungsten species were removed in 2 h, by employing 75 mg of MWCNTs from the aqueous solution containing 10 ppm of tungsten. Adsorption equilibrium data were fitted by the three isotherm models namely the Langmuir, Freundlich, and Sips isotherms and best described by a three-parameter Sips model. The maximum experimental adsorption capacity of MWCNTs for tungsten was 17.64 mg/g, while the adsorption capacity anticipated by the Langmuir and Sips isotherm models was 20.58 and 25.18 mg/g, respectively. The adsorption kinetic data was adequately fitted by a pseudo-second-order model. Our present findings ascertained that MWCNTs could be a potential adsorbent for the removal of tungsten species from the aqueous phase.
Show more [+] Less [-]The short-term effects of air pollution on respiratory disease hospitalizations in 5 cities in Poland: comparison of time-series and case-crossover analyses Full text
2020
Slama, Alessandro | Śliwczyński, Andrzej | Woźnica-Pyzikiewicz, Jolanta | Zdrolik, Maciej | Wiśnicki, Bartłomiej | Kubajek, Jakub | Turżańska-Wieczorek, Olga | Studnicki, Marcin | Wierzba, Waldemar | Franek, Edward
Very few publications have compared different study designs investigating the short-term effects of air pollutants on healthcare visits and hospitalizations for respiratory tract diseases. This study describes, using two different study designs (a case-crossover design and a time-series analysis), the association of air pollutants and respiratory disease hospitalizations. The study has been conducted on 5 cities in Poland on a timeline of almost 4 years. DLNM and regression models were both used for the assessment of the short-term effects of air pollution peaks on respiratory hospitalizations. Both case-crossover and time-series studies equally revealed a positive association between air pollution peaks and hospitalization occurrences. Results were provided in the form of percentage increase of a respiratory visit/hospitalization, for each 10-μg/m³ increment in single pollutant level for both study designs. The most significant estimated % increases of hospitalizations linked to increase of 10 μg/m³ of pollutant have been recorded in general with particulate matter, with highest values for 24 h PM₂.₅ in Warsaw (6.4%, case-crossover; 4.5%, time series, respectively) and in Białystok (5.6%, case-crossover; 4.5%, time series, respectively). The case-crossover analysis results have shown a larger CI in comparison to the results of the time-series analysis, while the lag days were easier to identify with the case-crossover design. The trends and the overlap of the results occurring from both methods are good and show applicability of both study designs to air pollution effects on short-term hospitalizations.
Show more [+] Less [-]Protective effects of Artemisia judaica extract compared to metformin against hepatorenal injury in high-fat diet/streptozotocine-induced diabetic rats Full text
2020
Albasher, Gadah | Alwahaibi, Mona | Abdel-Daim, Mohamed M. | Alkahtani, Saad | Almeer, Rafa
Diabetes mellitus (DM) is one of the most dangerous incurable diseases that affects a large number of people worldwide. Artemisia species have various protective activities and are widely used for the control of diabetes in folkloric medicine. Therefore, the current study was designed to illustrate the protective effect of oral administration of Artemisia judaica extract (AjE) against hepatorenal damage in a high-fat diet/streptozotocin (HFD/STZ) rat model of hyperlipidemia and hyperglycemia. Animals were divided into five groups—control, AjE, HFD/STZ, HFD/STZ-AjE (300 mg/kg), and HFD/STZ-MET (100 mg/kg)—and treated daily for 28 days. The results revealed that STZ-injected rats showed marked hyperglycemia and hypoinsulinemia in addition to high levels of cholesterol, triglycerides, and low- and high-density lipoproteins compared to control rats. Significant elevations in hepatic (AST and ALT) and renal (urea, uric acid, and creatinine) function markers were observed in the serum of diabetic rats. Additionally, STZ injection caused remarkable elevations in lipid peroxidation and nitric oxide levels as well as suppression of antioxidant markers (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione). Marked elevations in TNF-α and Bax levels with a decline in Bcl-2 levels were detected after STZ injection. Furthermore, TGF-β1 expression levels were significantly upregulated in the liver and kidney tissues. Rats that received AjE or MET showed significant improvement in most of the aforementioned parameters, and the protective efficacy was higher for AjE than for MET. Histopathological screening confirmed the biochemical findings. Conclusively, our results illustrated the antihyperglycemic, antihyperlipidemic, antioxidant, anti-inflammatory, and antiapoptotic activities of AjE against hepatorenal injury in HFD/STZ-induced diabetes.
Show more [+] Less [-]Effect of different bypass rates and unit area ratio in hybrid constructed wetlands Full text
2020
Gonzalo, Omar Gael | Ruiz, Isabel | Soto, Manuel
This study presents the performance of a hybrid constructed wetland (Bp(VF + HF)₂:₁) system which consists of an unsaturated vertical flow (VF) unit followed by a saturated down-flow unit simulating horizontal flow (HF) with HF/VF area ratio of 0.5 and influent bypass to the HF unit. Treating synthetic wastewater simulating municipal wastewater, optimum total nitrogen (TN) removal (57%) was reached at 39% bypass and surface loading rate (SLR) of 33 g BOD₅/m² day and 9.7 g TN/m² day (overall system). On the other hand, treating actual municipal wastewater, the system reached 63% TN removal at 30% bypass and SLR of 18 g BOD₅/m² day and 4.7 g TN/m² day. Surface removal rates reached 5.5 and 3.0 g TN/m² day for synthetic and municipal wastewater. Surface nitrification rate in the VF unit was in the range of 5.0–7.4 and 3.6–3.8 g N/m² day for synthetic and municipal wastewater, respectively, indicating a large effect of wastewater characteristics on the nitrification process. Infiltration rate in the VF unit remained high and far from clogging risk. Overall greenhouse gas emissions were 0.11 (N₂O) and 0.41 (CH₄) g/m² day which corresponded to emissions factors (relative to total organic carbon and TN influent) of 0.7% (N₂O) and 3.6% (CH₄). Compared with a similar system with a different HF/VF area ratio of 2.0, organic matter and nitrogen removal efficiency was similar, but surface removal rates were about 3 times higher.
Show more [+] Less [-]Experimental Investigation of Boron Removal Mechanism from Wastewater by Calcined Ettringite Full text
2020
Fuchida, Shigeshi | Hobo, Shungo | Tsuchiya, Kosuke | Tanaka, Yoshiyuki | Nakamura, Takeshi | Tokoro, Chiharu
The development of efficient and inexpensive boron removal techniques is required to treat wastewater from many industrial processes. We investigated the removal mechanism of boron from wastewater by calcinated ettringite, a concrete sludge, and compared the advantage of this method to coprecipitation with ettringite. The amount of boron remaining in solution decreased slightly from an initial concentration of 2.3 mmol/dm³ to 1.3–1.4 mmol/dm³ after reaction for 60 min with ettringites calcinated at 55 and 65 °C. The boron removal efficiency increased greatly, with only 0.30 mmol/dm³ remaining in solution after treatment for 60 min with samples calcinated at 75 °C, but samples calcinated at 95 and 175 °C removed slightly less boron than those calcinated at 75 °C. This enhancement of boron removal performance is due to the amorphization of the ettringite structure by calcination. However, excess heating inhibits ion exchange between the sulfate ions in the ettringite and the borate ions in the solution. The coprecipitation method also achieved efficient boron removal at high Al/B molar ratio (0.44 mmol/dm³ boron remaining after 60 min). However, uptake by a different amorphous precipitant became the dominant removal mechanism. Large amounts of sludge are generated by this method. Adsorption using calcinated ettringite is therefore the optimal method for the efficient and inexpensive removal of boron from wastewater.
Show more [+] Less [-]UV-LED for Safe Effluent Reuse in Agriculture Full text
2020
Silva, Noely Bochi | Leonel, Lays Paulino | Tonetti, Adriano Luiz
In the face of the water scarcity problem, the use of treated wastewater emerges as a viable alternative to meet the demand of the agricultural sector, the main consumer of available water in the world. Thus, the development of technologies to provide safe wastewater reuse is a priority. We evaluated the reduction rate of the fecal indicator Escherichia coli naturally present in effluent from an urban wastewater treatment plant (WWTP) submitted to UV-LED (Ultraviolet-Light-Emitting Diodes) radiation, emitting UVA (365 and 405 nm) or UVC (255 and 280 nm), used alone or coupled. The 280-nm wavelength seems to be crucial to the success of the disinfection systems, as all the programs that used this wavelength reached a 4-log reduction of E. coli.
Show more [+] Less [-]On the Removal of the Cr(VI) in Water by an Ordered Mesoporous Carbon Material: Kinetic and Isotherm Studies Full text
2020
Zhou, Yufeng | Zhang, Xi | Zhang, Haidong | Xiong, Kun | Chen, Jia | Shen, Yu | Tang, Yuantao | Li, Xiaojie
In this work, an ordered mesoporous carbon material CMK-3 was synthesized and tested in the adsorption of Cr(VI) in water with an activated carbon material (AC) as the control. Properties of CMK-3 have been characterized by means of Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy. In the adsorption of Cr(VI) in water, the adsorption rate and adsorption capacity of CMK-3 were found to be better than that of AC. A careful study on the adsorption kinetics and isotherms of Cr(VI) on CMK-3 was taken. The adsorption data of Cr(VI) on CMK-3 had been analyzed by pseudo-first-order, pseudo-second-order, particle diffusion, Elovich, Double constant, and Exponential function kinetic models, which revealed that the kinetic adsorption of Cr(VI) on CMK-3 is well accorded with pseudo-second-order kinetic model. The corresponding parameters for each model are obtained. According to the fitting of Langmuir, Freundlich, and Temkin models, the adsorption of Cr(VI) on CMK-3 was well described by Langmuir model to be a single-molecule layer adsorption. The adaptation of the adsorption of Cr(VI) on CMK-3 to Langmuir adsorption model and pseudo-second-order model suggests that the adsorption of Cr(VI) on CMK-3 can be highly affected by its chemical property although its textural properties also can remarkably affect its adsorption behavior.
Show more [+] Less [-]Economical and Technological Aspects of Copper Removal from Water Using a Geopolymer and Natural Zeolite Full text
2020
da Costa Rocha, Ana Cláudia | Scaratti, Gidiane | Moura-Nickel, Camilla Daniela | da Silva, Thiago Lopes | Gurgel Adeodato Vieira, Melissa | Peralta, Rosane Marina | Peralta, Rosely Aparecida | de Noni, Agenor Jr | Peralta Muniz Moreira, Regina de Fatima
This study reports the efficiency of a synthesized eco-friendly geopolymer (7.5 wt% of coal fly ash incorporated into its composition) as an adsorbent for the removal of Cu(II) from an aqueous solution and a real water matrix. The results obtained were compared with a commercial natural zeolite used as an adsorbent of toxic metals in Brazil. The effect of the operating conditions on the adsorption kinetics and equilibrium were studied in a finite bath and in a fixed bed column. The adsorption kinetics curves obey the pseudo-first-order model for both materials. The geopolymer presented higher adsorption capacity than zeolite, and values for the qₘₐₓ_gₑₒ/qₘₐₓ_zₑₒ ratio were 1.13, 1.92, and 2.56 at temperatures of 25, 40, and 55 °C, respectively. The isotherms obtained in the thermodynamic study are favorable and spontaneous adsorption process. The adsorption processes are endothermic. The geopolymer showed higher adsorption efficiency than the zeolite in a fixed-bed column, and even with the presence of substances in the natural water sample, the Cu(II) removal capacity of the geopolymer is 3–4 times higher than that of the zeolite. A cost analysis was also performed, the geopolymer was found to be a more economical adsorbent than the commercial zeolite.
Show more [+] Less [-]A Simple and Green Vortex-Assisted Switchable Solvent-Based Microextraction Method by Using Schiff Base Ligand Complexation for Iron Determination in Mineral Spring Water Samples Prior to Slotted Quartz Tube Flame Atomic Absorption Spectrophotometry Full text
2020
Kasa, Nursu Aylin | Bakirdere, Emine Gülhan | Bakirdere, Sezgin
In this study, a vortex-assisted switchable solvent microextraction (VA-SSME) method was developed for the determination of iron by slotted quartz tube flame atomic absorption spectrometry (SQT-FAAS). A ligand synthesized from the reaction of ortho-phenylenediamine and 5-bromosalicylaldehyde was used to form a coordinate complex of iron. All experimental variables such as switchable solvent amount, sodium hydroxide concentration, sodium hydroxide amount, and diluent amount were optimized to increase extraction efficiency for the iron complex. Optimum conditions were applied to aqueous standard solutions in the range of 20–750 ng/mL, and the percent relative standard deviation (%RSD) was less than 2.0%. The limit of detection (LOD) and limit of quantification (LOQ) were determined as 4.8 and 16.2 ng/mL, respectively. The optimized method recorded approximately 53 times enhancement according to the conventional FAAS system. The proposed method was applied to mineral spring water samples, and satisfactory percent recovery results (100–105%) were obtained for iron, indicating good applicability in addition to high accuracy.
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