scholarly journals Purification Efficiency of Three Combinations of Native Aquatic Macrophytes in Artificial Wastewater in Autumn

2021 ◽  
Vol 18 (11) ◽  
pp. 6162
Author(s):  
Lei Xu ◽  
Siyu Chen ◽  
Ping Zhuang ◽  
Dongsheng Xie ◽  
Xiaoling Yu ◽  
...  
Keyword(s):  
Native Species ◽  
Aquatic Macrophytes ◽  
Oxygen Demand ◽  
Plant Residue ◽  
Control Group ◽  
Acorus Calamus ◽  
Removal Rates ◽  
Significant Deterioration ◽  
Purification Efficiency ◽  
Saururus Chinensis

Water pollution caused by excessive nutrient and biological invasion is increasingly widespread in China, which can lead to problems with drinking water as well as serious damage to the ecosystem if not be properly treated. Aquatic plant restoration (phytoremediation) has become a promising and increasingly popular solution. In this study, eight native species of low-temperature-tolerant aquatic macrophytes were chosen to construct three combinations of aquatic macrophytes to study their purification efficiency on eutrophic water in large open tanks during autumn in Guangzhou City. The total nitrogen (TN) removal rates of group A (Vallisneria natans + Ludwigia adscendens + Monochoria vaginalis + Saururus chinensis), group B (V. natans + Ipomoea aquatica + Acorus calamus + Typha orientalis), and group C (V. natans + L. adscendens + Schoenoplectus juncoides + T. orientalis) were 79.10%, 46.39%, and 67.46%, respectively. The total phosphorus (TP) removal rates were 89.39%, 88.37%, and 91.96% in groups A, B, and C, respectively, while the chemical oxygen demand (COD) removal rates were 93.91%, 96.48%, and 92.78%, respectively. In the control group (CK), the removal rates of TN, TP, and COD were 70.42%, 86.59%, and 87.94%, respectively. The overall removal rates of TN, TP, and COD in the plant groups were only slightly higher than that in CK group, which did not show a significant advantage. This may be related to the leaf decay of some aquatic plants during the experiment, whereby the decay of V. natans was the most obvious. The results suggest that a proper amount of plant residue will not lead to a significant deterioration of water quality.

scholarly journals Treatment performances of French constructed wetlands: results from a database collected over the last 30 years

2015 ◽  
Vol 71 (9) ◽  
pp. 1333-1339 ◽  
Author(s):  
A. Morvannou ◽  
N. Forquet ◽  
S. Michel ◽  
S. Troesch ◽  
P. Molle
Keyword(s):  
Constructed Wetlands ◽  
Oxygen Demand ◽  
Pollutant Removal ◽  
Vertical Flow ◽  
Removal Rates ◽  
Waste Stabilization Ponds ◽  
Small Communities ◽  
Technical Department ◽  
In Series ◽  
High Chemical Oxygen Demand

Approximately 3,500 constructed wetlands (CWs) provide raw wastewater treatment in France for small communities (<5,000 people equivalent). Built during the past 30 years, most consist of two vertical flow constructed wetlands (VFCWs) in series (stages). Many configurations exist, with systems associated with horizontal flow filters or waste stabilization ponds, vertical flow with recirculation, partially saturated systems, etc. A database analyzed 10 years earlier on the classical French system summarized the global performances data. This paper provides a similar analysis of performance data from 415 full-scale two-stage VFCWs from an improved database expanded by monitoring data available from Irstea and the French technical department. Trends presented in the first study are confirmed, exhibiting high chemical oxygen demand (COD), total suspended solids (TSS) and total Kjeldahl nitrogen (TKN) removal rates (87%, 93% and 84%, respectively). Typical concentrations at the second-stage outlet are 74 mgCOD L−1, 17 mgTSS L−1 and 11 mgTKN L−1. Pollutant removal performances are summarized in relation to the loads applied at the first treatment stage. While COD and TSS removal rates remain stable over the range of applied loads, the spreading of TKN removal rates increases as applied loads increase.

scholarly journals Degradation of Landfill Leachate Using UV-TiO2 Photocatalysis Combination with Aged Waste Reactors

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 946
Author(s):  
Chunlian Wang ◽  
Xiaojie Sun ◽  
Huijun Shan ◽  
Hongxia Zhang ◽  
Beidou Xi
Keyword(s):  
Tio2 Nanoparticles ◽  
Landfill Leachate ◽  
Control Method ◽  
Irradiation Time ◽  
Combined Treatment ◽  
Oxygen Demand ◽  
Infrared Spectrometry ◽  
Process Conditions ◽  
Optimal Process ◽  
Removal Rates

This study explored the performance of TiO2 nanoparticles in combination with aged waste reactors to treat landfill leachate. The optimum conditions for synthesis of TiO2 were determined by a series of characterizations and removal rates of methyl orange. The effect of the ultraviolet irradiation time, amount of the catalyst, and pH on the removal efficiency for the chemical oxygen demand (COD) and color in the leachate was explored to determine the optimal process conditions, which were 500 min, 4 g/L and 8.88, respectively. The removal rates for COD and chroma under three optimal conditions were obtained by the single factor control method: 89% and 70%; 95.56% and 70%; and 85% and 87.5%, respectively. Under optimal process conditions, the overall average removal rates for ammonium nitrogen (NH4+–N) and COD in the leachate for the combination of TiO2 nanoparticles and an aged waste reactor were 98.8% and 32.5%, respectively, and the nitrate (NO3−–N) and nitrite nitrogen (NO2–N) concentrations were maintained at 7–9 and 0.01–0.017 mg/L, respectively. TiO2 nanoparticles before and after the photocatalytic reaction were characterized by emission scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and Fourier transform infrared spectrometry. In addition, TiO2 nanoparticles have excellent recyclability, showing the potential of the photocatalytic/biological combined treatment of landfill leachate. This simulation of photocatalysis-landfilling could be a baseline study for the implementation of technology at the pilot scale.

INOVASIA Study: A Randomized Open Controlled Trial to Evaluate Pravastatin to Prevent Preeclampsia and its Effects on sFlt1/PLGF Levels

2021 ◽  
Author(s):  
Muhammad Ilham Aldika Akbar ◽  
Angelina Yosediputra ◽  
Raditya Eri Pratama ◽  
Nur Lailatul Fadhilah ◽  
Sulistyowati Sulistyowati ◽  
...  
Keyword(s):  
High Risk ◽  
Pregnant Women ◽  
Controlled Trial ◽  
Intervention Group ◽  
Perinatal Outcomes ◽  
Neonatal Morbidity ◽  
Clinical Risk Factor ◽  
Control Group ◽  
Significant Deterioration ◽  
Plgf Ratio

Objectives To evaluate the effect of pravastatin to prevent preeclampsia (PE) in pregnant women at a high risk of developing preeclampsia and the maternal and perinatal outcomes and the sFlt1/PLGF ratio. Study Design This is an open labelled RCT part of INOVASIA trial. Pregnant women at a high risk of developing PE were recruited and randomized into an intervention group (40) and a control group (40). The inclusion criteria consisted of pregnant women with positive clinical risk factor and abnormal uterine artery doppler examination at 10-20 weeks gestational age. The control group received low dose aspirin (80 mg/day) and calcium (1 g/day), while the intervention group received additional pravastatin (20 mg twice daily) starting from 14-20 weeks gestation until delivery. Research blood samples were collected before the first dose of pravastatin and before delivery. The main outcome was the rate of maternal preeclampsia, maternal-perinatal outcomes, and sFlt-1, PLGF, sFlt-1/PlGF ratio and sEng levels. Results The rate of preeclampsia was (non-significantly) lower in the pravastatin group compared with the control group (17.5% vs 35%). The pravastatin group also had a (non-significant) lower rate of severe preeclampsia, HELLP syndrome, acute kidney injury and severe hypertension. The rate of (iatrogenic) preterm delivery was significantly (p=0.048) lower in the pravastatin group (n=4) compared with the controls (n=12). Neonates in the pravastatin group had significantly higher birthweights (2931 + 537 vs 2625 + 872 g; p=0.006), lower Apgar scores < 7 (2.5 vs 27.5%, p=0.002), composite neonatal morbidity (0 vs 20%, p=0.005) and NICU admission rates (0 vs 15%, p=0.026). All biomarkers show a significant deterioration in the control group compared with non significant changes in the pravastatin group. Conclusions Pravastatin holds promise in the secondary prevention of preeclampsia and placenta-mediated adverse perinatal outcomes by improving the angiogenic imbalance.

Novel biofilm reactor for denitrification of municipal wastewater

2018 ◽  
Vol 78 (7) ◽  
pp. 1566-1575 ◽  
Author(s):  
S. S. Rathnaweera ◽  
B. Rusten ◽  
K. Korczyk ◽  
B. Helland ◽  
E. Rismyhr
Keyword(s):  
Carbon Source ◽  
Municipal Wastewater ◽  
Low Cost ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Biofilm Reactor ◽  
Treated Wastewater ◽  
Removal Rates ◽  
Good Filter ◽  
Solids Removal

Abstract A pilot-scale CFIC® (continuous flow intermittent cleaning) reactor was run in anoxic conditions to study denitrification of wastewater. The CFIC process has already proven its capabilities for biological oxygen demand removal with a small footprint, less energy consumption and low cost. The present study focused on the applicability for denitrification. Both pre-denitrification (pre-DN) and post-denitrification (post-DN) were tested. A mixture of primary treated wastewater and nitrified wastewater was used for pre-DN and nitrified wastewater with ethanol as a carbon source was used for post-DN. The pre-DN process was carbon limited and removal rates of only 0.16 to 0.74 g NOx-N/m²-d were obtained. With post-DN and an external carbon source, 0.68 to 2.2 g NO3-Neq/m²-d removal rates were obtained. The carrier bed functioned as a good filter for both the larger particles coming with influent water and the bio-solids produced in the reactor. Total suspended solids removal in the reactor varied from 20% to 78% (average 45%) during post-DN testing period and 9% to 70% (average 29%) for pre-DN. The results showed that the forward flow washing improves both the DN function and filtration ability of the reactor.

scholarly journals Oxygen demand during mineralization of aquatic macrophytes from an oxbow lake

2008 ◽  
Vol 68 (1) ◽  
pp. 61-67 ◽  
Author(s):  
I. Bianchini Jr. ◽  
MB. Cunha-Santino ◽  
AM. Peret
Keyword(s):  
Aquatic Macrophytes ◽  
Oxygen Demand ◽  
Oxbow Lake ◽  
Short Term ◽  
River Floodplain ◽  
Dissolved Carbon ◽  
Eichhornia Azurea ◽  
Aerobic Decomposition ◽  
Cyperus Giganteus ◽  
Egeria Najas

This study presents a kinetic model of oxygen consumption during aerobic decomposition of detritus from seven species of aquatic macrophytes: Cabomba furcata, Cyperus giganteus, Egeria najas, Eichhornia azurea, Salvinia auriculata, Oxycaryum cubense and Utricularia breviscapa. The aquatic macrophytes were collected from Óleo Lagoon situated in the Mogi-Guaçu river floodplain (SP, Brazil). Mineralization experiments were performed using the closed bottles method. Incubations made with lake water and macrophytes detritus (500 mL and 200 mg.L-1 (DM), respectively) were maintained during 45 to 80 days at 20 °C under aerobic conditions and darkness. Carbon content of leachates from aquatic macrophytes detritus and dissolved oxygen concentrations were analyzed. From the results we concluded that: i) the decomposition constants differ among macrophytes; these differences being dependent primarily on molecular and elemental composition of detritus and ii) in the short term, most of the oxygen demand seems to depend upon the demineralization of the dissolved carbon fraction.

scholarly journals Suitability of Macrophytes for Wastewater Treatment and Biogas Generation

2019 ◽  
Vol 9 (2S2) ◽  
pp. 16-18
Keyword(s):  
Wastewater Treatment ◽  
Water Hyacinth ◽  
Aquatic Macrophytes ◽  
Aquatic Macrophyte ◽  
Biogas Production ◽  
Oxygen Demand ◽  
Cow Dung ◽  
Water Lettuce ◽  
Before And After ◽  
Almost All

In this paper three sustainable approaches are made in waste management option. Firstly primary treated domestic sewage is treated by aquatic macrophytes using duckweed, water hyacinth and water lettuce. Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), Total Dissolved Solids (TDS), Phosphate, Nitrates are tested before and after. Result indicates in terms of water quality, almost all three plants shows same removal efficiencies. BOD and TSS removal efficiency is attained more than 95%. COD and TDS removal is reached upto 50% for almost all plants. Secondly the used aquatic macrophytes for wastewater treatment is again used for generation of biogas (water lettuce unit, duckweed unit, water lettuce unit). In addition to three aquatic macrophytes, sludge is collected from aquatic macrophyte unit for generation of biogas. Comparison is made with conventional cow dung biogas unit. Result indicates water lettuce and duckweed produce biogas at earlier stage itself and water hyacinth takes some time for starting of biogas production. This may be due to the structure and texture causes some time for decomposition. Sludge gives maximum biogas generation among all experimental setup. Also in this study cow dung did not give biogas more may be due to poor blend ratio of cow dung with water is one of the reason.

scholarly journals Public disclosure of industrial pollution: the PROPER approach for Indonesia?

2007 ◽  
Vol 12 (6) ◽  
pp. 739-756 ◽  
Author(s):  
JORGE H. GARCÍA ◽  
THOMAS STERNER ◽  
SHAKEB AFSAH
Keyword(s):  
Pollution Control ◽  
Positive Response ◽  
Oxygen Demand ◽  
Asian Financial Crisis ◽  
Control Group ◽  
Public Disclosure ◽  
Emissions Reductions ◽  
Level Data ◽  
Control Evaluation ◽  
Plant Level

ABSTRACTThis paper evaluates the effectiveness of the Program for Pollution Control Evaluation and Rating (PROPER) in Indonesia. PROPER, the first major public disclosure program in the developing world, was launched in June 1995; though it collapsed in 1998 with the Asian financial crisis, it is currently being revived. There have been claims of success for this pioneering scheme, yet little formal and conclusive analysis has been undertaken. We analyze changes in emissions concentrations (mg/L) using panel data techniques with plant-level data for participating firms and a control group. The results show that there was indeed a positive response to PROPER, especially among firms with poor environmental compliance records. The response was immediate, and firms pursued further emissions reductions in the following months. The total estimated reductions in biochemical oxygen demand (BOD) and chemical oxygen demand (COD) were approximately 32 per cent.

Does Ramadan Fasting Affect Hydration Status and Kidney Function in CKD Patients?

2018 ◽  
Vol 72 (3) ◽  
pp. 241-247 ◽  
Author(s):  
Shadia Hassan ◽  
Fadi Hassan ◽  
Nur Abbas ◽  
Kamal Hassan ◽  
Nihal Khatib ◽  
...  
Keyword(s):  
Kidney Function ◽  
Estimated Glomerular Filtration Rate ◽  
Blood Analysis ◽  
Hydration Status ◽  
Control Group ◽  
Significant Deterioration ◽  
Ramadan Fasting ◽  
Reasonable Degree ◽  
Fast Control ◽  
The Impact

Background/Aims: This study is the first of its kind to examine the impact of the Ramadan fasting on hydration status, plasma brain natriuretic peptide (BNP) levels, and kidney function in chronic kidney disease (CKD) patient. Methods: This prospective cohort study included 2 groups of patients with CKD grades 2–4: thirty-one Muslim patients who fasted the month of Ramadan (fasting group) and 26 Muslim patients who did not fast (control group). One week before the Ramadan fast, in the last week of the month of Ramadan (4 weeks), and 4 weeks after the end of the Ramadan month (8 weeks), hydration status and blood analysis of urea, creatinine and BNP levels were measured. Results: Among fasting patients, serum urea levels increased significantly (p = 0.024) during the last week of fasting and returned to basal levels at 4 weeks after the end of the Ramadan month, the estimated glomerular filtration rate did not change significantly at the end of fasting (p = 0.411), the hydration status indices and plasma BNP levels were significantly decreased after fasting (p ≤ 0.021) but returned to basal values 4 weeks thereafter. Conclusions: Patients with CKD grades 2–4 can fast throughout the month of Ramadan with no significant deterioration of renal functions and with a reasonable degree of safety.

Increased nitric oxide availability worsens the cardiac performance during early re-perfusion period in adult rats

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Faten M.A. Diab ◽  
Mahmoud H. Ayobe ◽  
Mohamed F. Abdel-Salam ◽  
Mohammed F.S. Otman ◽  
Enas A. Abdel-Hady
Keyword(s):  
Nitric Oxide ◽  
Flow Rate ◽  
Cardiac Performance ◽  
Control Group ◽  
Adult Rats ◽  
Significant Deterioration ◽  
No Donor ◽  
Langendorff Preparation ◽  
Perfusion Period ◽  
Myocardial Flow

Abstract Objectives Re-perfusion is the standard therapy for acute myocardial infarction, despite the associated pathologies that may contribute to irreversible myocardial injury. The present study aims to clarify the alterations in cardiac activities in response to experimental cardiac ischemic arrest followed by re-perfusion in isolated hearts perfused with nitric oxide (NO) donor, l-arginine, or NO inhibitor, Nω-Nitro-l-arginine methyl ester hydrochloride (l-NAME), to shed light on the possible role of NO in the re-perfusion process. Methods Hearts isolated from adult Wistar rats were studied on Langendorff preparation under basal conditions and during 30 min re-perfusion following 30 min of total global ischemia. Rats were randomly divided into three groups; control and l-arginine or l-NAME infused heart groups. Cardiac tissue content of malondialdhyde, catalase and nitrite was also measured. Results Compared to the control group, both l-arginine and l-NAME infused hearts showed increased basal chronotropy and myocardial flow rate. Following ischemia and during the whole period of re-perfusion, the three groups demonstrated significant deterioration in the inotropic activity and compromised myocardial flow rate. l-arginine infused hearts revealed depressed inotropy and chronotropy, weak systolic and diastolic functions with compromised myocardial flow at early 5 min of re-perfusion, yet with significantly higher myocardial flow rate by the end of re-perfusion. Conclusions Reducing NO availability by l-NAME revealed mild impact on the ischemia re-perfusion induced contractile dysfunction, whereas excess NO worsens cardiac performance at the early re-perfusion period.

scholarly journals Causes of acromion and scapular spine fractures following reverse shoulder arthroplasty: a retrospective analysis and literature review

2020 ◽  
Vol 44 (12) ◽  
pp. 2673-2681
Author(s):  
Richard W. Nyffeler ◽  
Bartu Altioklar ◽  
Philipp Bissig
Keyword(s):  
Bone Quality ◽  
Shoulder Arthroplasty ◽  
Reverse Shoulder Arthroplasty ◽  
Total Shoulder Arthroplasty ◽  
Control Group ◽  
Time Interval ◽  
Spine Fractures ◽  
Poor Bone Quality ◽  
Significant Deterioration ◽  
Scapular Spine

Abstract Purpose Fractures of the acromion and the scapular spine are serious complications after reverse total shoulder arthroplasty. They concern about 4 to 5% of the patients and always result in a significant deterioration of shoulder function. Different causes have been taken into consideration, particularly stress or fatigue fractures. The purpose of the present study was to analyse our own cases and to discuss the causes reported in the literature. Methods We reviewed our shoulder arthroplasty registry and the consultation reports of the last ten years. The charts and radiographs of all patients who had a post-operative fracture of the acromion or the scapular spine were carefully examined and the results were compared with those of an age- and gender-matched control group. Results Twelve patients with an average age of 79 years sustained a fracture of the acromion (n = 6) or the scapular spine (n = 6). The time interval between the operation and the fracture averaged 26 months and ranged from three weeks to 70 months. Eight patients (67%) had a trauma. Seven of them reported a fall on the corresponding shoulder and one a heavy blow on the acromion. The four non-traumatic fractures were attributed to poor bone quality. All 12 patients had immediate pain and difficulty to actively elevate the affected arm. The time interval between the fracture and its diagnosis averaged ten weeks (0 to 10 months). At final follow-up, all patients could reach their face and refused further surgery. Two patients rated their result as good, six as acceptable and four as poor. Conclusions Our study cannot support the hypothesis that most acromion and scapular spine fractures after RSA are the result of increased tension in the deltoid or stress fractures. In our series, the majority of the fractures were related to a fall. Implantation of a reverse prosthesis exposes the acromion and makes it more vulnerable to direct trauma. Non-traumatic fractures were associated with poor bone quality.

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