scholarly journals Design of up-flow aerated filters for the removal of iron from groundwater

2020 ◽  
Vol 20 (8) ◽  
pp. 3233-3241
Author(s):  
T. Thinojah ◽  
B. Ketheesan ◽  
G. B. B. Herath
Keyword(s):  
Removal Efficiency ◽  
Combined Treatment ◽  
Column Experiment ◽  
Kinetic Studies ◽  
Treatment Method ◽  
World Health ◽  
Drinking Water Standard ◽  
Air Supply ◽  
Pseudo Second Order ◽  
Health Organization

Abstract Groundwater contains iron (Fe) that can be difficult to remove by singular physical–chemical methods. The aim of this presented study was to investigate the suitability of up-flow aerated filters as an upgrading step for the removal of total Fe from groundwater. Granular activated carbon (GAC) was applied as a pollutant carrier and compared with Bio-Pac media (BPM) by conducting a column test to treat synthetic groundwater (SGW). Initially two adsorption kinetic studies were done for GAC. The effect of influent Fe concentration, hydraulic retention time (HRT) and air supply to the system were investigated using a column experiment. The sorption result follows pseudo-second-order kinetics with an adsorption amount of 1.36 mg/g. The column experiment results show that around 99% and 70% Fe removal efficiency can be achieved for the best condition of 3 mg/L influent Fe concentration with seven hours HRT for GAC and BPM respectively. The air supply into the column did not show any improvement in Fe removal efficiency. The performance of GAC is found to be much better than that of BPM. All over, the new combined treatment method of aeration followed by filtration was demonstrated to be an effective technique for Fe removal from groundwater and also satisfied the World Health Organization (WHO) drinking water standard for Fe concentration.

scholarly journals The effectiveness of aspirin for migraine prophylaxis: a systematic review

2017 ◽  
Vol 135 (1) ◽  
pp. 42-49 ◽  
Author(s):  
Cristina Pellegrino Baena ◽  
Raíssa Campos D’Amico ◽  
Helena Slongo ◽  
André Russowsky Brunoni ◽  
Alessandra Carvalho Goulart ◽  
...  
Keyword(s):  
Systematic Review ◽  
Total Population ◽  
Combined Treatment ◽  
Risk Of Bias ◽  
World Health ◽  
Optimal Dosage ◽  
Health Organization ◽  
The University

ABSTRACT CONTEXT AND OBJECTIVE: Many researchers have suggested that aspirin prevents migraines. However, the evidence is unclear. The aim of this study was to analyze the available evidence on the effect of aspirin as a migraine prophylactic. DESIGN AND SETTING: Systematic review, conducted at the Pontifícia Universidade Católica do Paraná, Brazil, and at the University of São Paulo, Brazil. METHODS: We performed electronic searches in the databases of MEDLINE/PubMed, Embase, WEB OF SCIENCE, the World Health Organization, CENTRAL and OpenGrey, and we also searched manually for interventional studies published before April 2016 that compared the effects of aspirin with a control, in adults. Two authors independently extracted data on the publication, population recruited, intervention (aspirin dosage, follow-up and combined treatment) and main outcomes (frequency, severity and duration of migraine). We evaluated the quality of the studies using the Cochrane risk-of-bias tool. RESULTS: Our search retrieved 1,098 references, of which 8 met the selection criteria for this systematic review. The total population was 28,326 participants (18-64 years old); most (96%) were men. The dosage varied from 50 to 650 mg/day across the studies. The risk of bias was generally low or unclear. The only outcome for which most of the studies included (6/8) reported a significant reduction was frequency of migraine, which was reduced at an aspirin dosage of at least 325 mg/day. CONCLUSION: Aspirin can reduce the frequency of migraines. However, the optimal dosage is unclear.

scholarly journals Arsenic in drinking water: not just a problem for Bangladesh

2009 ◽  
Vol 2 (1) ◽  
pp. 51-64 ◽  
Author(s):  
D. van Halem ◽  
S. A. Bakker ◽  
G. L. Amy ◽  
J. C. van Dijk
Keyword(s):  
Drinking Water ◽  
World Health ◽  
Drinking Water Standard ◽  
Naturally Occurring ◽  
Arsenic In Groundwater ◽  
Tube Wells ◽  
The Usa ◽  
Health Organization ◽  
Near Future ◽  
High Arsenic

Abstract. For more than a decade it has been known that shallow tube wells in Bangladesh are frequently contaminated with arsenic concentrations at a level that is harmful to human health. By now it is becoming clear that a disaster of an unheard magnitude is going on: the World Health Organization fears that in the near future 1 in every 10 adult deaths in Bangladesh will be caused by arsenic-related cancers. Other studies show that problems with arsenic in groundwater/drinking water occur in many more countries worldwide, such as in the USA and China. In Europe the focus on arsenic problems is confined to countries with high arsenic levels in their groundwater, such as Romania, Hungary and Italy. In most other European countries, the naturally occurring arsenic concentrations are lower than the drinking water standard of 10 μg L−1. However, from the literature review presented in this paper, it may also be concluded that using the European standard, health risks cannot be excluded. It is therefore recommended that the current arsenic standard be reconsidered.

scholarly journals Cultivated autologous oral mucosal epithelial transplantation

2021 ◽  
Vol 23 (1) ◽  
pp. 171-177
Author(s):  
S. A. Borzenok ◽  
B. E. Malyugin ◽  
M. Yu. Gerasimov ◽  
D. S. Ostrovsky
Keyword(s):  
Visual Acuity ◽  
Cell Therapy ◽  
Visual Impairment ◽  
Treatment Method ◽  
World Health ◽  
Epithelial Culture ◽  
The World ◽  
Corneal Blindness ◽  
New Treatment ◽  
Health Organization

According to the World Health Organization, corneal blindness is the fourth most common cause of blindness and visual impairment worldwide. In Russia, up to 18% of blindness is caused by corneal damage. Limbal stem cell deficiency (LSCD) is one of the causes of corneal blindness and visual impairment due to anterior epithelial replacement with fibrovascular pannus. Bilateral LSCD may develop in patients with aniridia, Steven-Jones syndrome, and severe corneal burns of both eyes, leading to severe decrease in visual acuity in both eyes and, as a consequence, physical disability associated with blindness. In such cases, cell therapy, based on autologous oral epithelial culture as an alternative to allogeneic limbus transplants, is proposed for reconstruction of the anterior corneal epithelium. This new treatment method promotes corneal reepithelization, better visual acuity, reduced nonspecific ocular complaints and improved quality of life of patients. The effectiveness and significant increase in the frequency of transparent engraftment of donor corneas after cell therapy drives huge interest in this topic all over the world. This review presents literature data on the features of histotopography and methods for obtaining a cultured autologous oral mucosal epithelium, on cell markers that are used to identify epithelial cells, and on methods for creating cell grafts for subsequent transplantation to the corneal surface in LSCD patients.

Groundwater Treatment via Ozonation

2019 ◽  
pp. 200-225
Author(s):  
Nor Azliza Akbar ◽  
Zaidin Bin Matsin ◽  
Siti Fatihah Binti Ramli
Keyword(s):  
Drinking Water ◽  
Ex Situ ◽  
World Health ◽  
Ozone Treatment ◽  
Drinking Water Standard ◽  
Inorganic Substances ◽  
Inorganic Pollutant ◽  
Good Potential ◽  
Health Organization

Groundwater is the source of drinking water that needs to be maintained from pollution. Groundwater pollution is a major problem caused by human activities that are invaluable to human health. When high levels of organic and inorganic substances do not exceed the standard of drinking water, various studies have been made by researchers to overcome the problem. Various alternatives such as in-situ and ex-situ treatment have been carried out to eliminate pollutants from groundwater. Among the treatment, ozone becomes a major alternative because of its effectiveness in treating raw water. Ozone treatment has several advantages such as disinfectants, oxidize of organic and inorganic pollutant, and remove taste and color from groundwater. The performance of ozonation process becomes better when combined with other treatments. Therefore, application of ozone can replace chlorine because of its good potential to improve quality of groundwater effluent and comply drinking water standard adopted by World Health Organization.

Inactivation of E. coli by copper and silver wire in the presence of synthetic sunlight for safe drinking water

2016 ◽  
Vol 6 (4) ◽  
pp. 576-583
Author(s):  
Graham McLaughlin ◽  
Vikramjit Bajwa ◽  
Mukund Shukla ◽  
Kevin Hall ◽  
Praveen Saxena
Keyword(s):  
Drinking Water ◽  
Low Cost ◽  
Treatment Method ◽  
Combination Method ◽  
World Health ◽  
Health Concern ◽  
Bacterial Inactivation ◽  
Emerging Nations ◽  
Health Organization ◽  
Pure Cu

Bacterially-contaminated water is a major health concern leading to infectious diseases in emerging nations. The use of copper (Cu) and silver (Ag) wire independently, and Cu wire in combination with synthetic sunlight (SySu), were investigated as a low-cost water treatment method. Water inoculated with 1,100 colony forming units/mL of Escherichia coli was treated with one of these four treatments: (1) 50 cm2/L surface area (SA) pure Cu wire; (2) 37.8 W/m2 SySu irradiation; (3) a 50 cm2/L SA pure Cu wire combined with the 37.8 W/m2 SySu irradiation; and (4) 5 cm2/L pure Ag wire. An improved rate of bacterial inactivation was achieved using the combined Cu-SySu treatment method compared to either treatment applied independently. When given independently, the Ag wire treatment was more effective than the Cu wire treatment. Cu and Ag content in the water, tested at the end of the experiment, remained far below the safety limits suggested by the World Health Organization. The Cu-SySu combination method has a great potential to be used as a low-cost, re-useable, low-maintenance method of choice for purification of contaminated drinking water.

scholarly journals Assessment of Groundwater Quality for Industrial Purposes Using Geographical Information System (GIS) in Zahedan, Sistan and Baluchestan Province, Iran

2020 ◽  
Author(s):  
Shahnaz Sargazi ◽  
Seyed Ali Almodaresi ◽  
Ali Asghar Ebrahimi ◽  
Arash Dalvand ◽  
Hossein Sargazi ◽  
...  
Keyword(s):  
Water Quality ◽  
High Rate ◽  
Geographical Information ◽  
Localized Corrosion ◽  
World Health ◽  
Allowable Limit ◽  
Drinking Water Standard ◽  
Mapping Techniques ◽  
Health Organization ◽  
The Cost

Introduction: Water quality is essential for industries because they play an important role in countries’ economic development. Groundwater is one of the most widely used resources, and when the ionic constituents were increasing higher than the allowable limit, it increases the cost of maintenance and production in the industries. Materials and Methods: In order to evaluate groundwater corrosiveness and scaling potential in Zahedan City,  29 groundwater wells and GIS-based geostatistical mapping techniques were analyzed clemically. The physicochemical parameters were invetsiagted and the most popular corrosion and scaling indices were determined as Langelier Index (LI), Aggressive Index (AI), Ryznar Index (RI), Puckorius Index (PI), and Larson–Skold Index (LS). Using ArcGIS 10.6.1 software, the zoning maps were plotted for LI, AI, RI, PI, and LS indices. Results: The results showed that total dissolved solids (TDS) and electrical conductivity (EC) values in all of the samples exceeded the World Health Organization (WHO) drinking water standard. AI values of 58.62% samples showing moderate corrosiveness, and the remaining 17 samples have a scaling nature with very less corrosivity. Based on the LI values, 55.2% of samples have a corrosive nature. Concerning RI values, 59% of the samples have a corrosive tendency. According to the PI values, the entire groundwater of this region has a significant corrosive tendency, and 96% of samples exceeded the LS > 1.2, showing a high rate of localized corrosion. Conclusion: The zoning and spatial analysis of water quality showed that water quality was treated for industrial purposes in the entire studied region.

scholarly journals Successful Treatment of a Spinal Clear Cell Meningiomas Patient With Anti-PD-1 Plus Anti- Angiogenesis

2021 ◽  
Author(s):  
Yong Wang ◽  
Baoyan Liu ◽  
Rongjie Tao ◽  
Yingxue Qi ◽  
Ningning Luo ◽  
...  
Keyword(s):  
Clear Cell ◽  
Treatment Options ◽  
Reference Value ◽  
Treatment Method ◽  
Disease Recurrence ◽  
World Health ◽  
High Recurrence Rate ◽  
Who Grade ◽  
Primary Tumors ◽  
Health Organization

Abstract Clear cell meningioma (CCM), an unusual subtype of World Health Organization (WHO) grade II meningioma, represents only 0.2– 0.8% of meningiomas. Spinal CCMs are even rarer with unique clinical features: more common in younger patients; more likely to appear in lumbar spine; high recurrence rate. Although surgery and radiotherapy are the most common treatment for primary tumors and disease recurrence, there are lack of treatment options for recurrent or metastasis disease. It is urgent need to explore new effective treatment method. In our case, we firstly reported a rare spinal CCM patient with PD-L1 positive and multiple metastases benefiting from PD-1 inhibitor plus anti- angiogenesis therapy. This treatment program is effective, safe, and has a strong therapeutic reference value, which provides promising treatment options and the direction of future clinical trials for spinal CCMs.

scholarly journals RELATIONSHIP BETWEEN FLUORIDE CONTENTS IN GROUNDWATER AND PREVALENCE OF FLUOROSIS IN TAY SON DISTRICT, BINH DINH PROVINCE, VIETNAM

2018 ◽  
Vol 54 (4B) ◽  
pp. 240
Author(s):  
Phan Nhu Nguyet
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Dental Fluorosis ◽  
Fluoride Concentration ◽  
World Health ◽  
Well Water ◽  
Drinking Water Standard ◽  
Limit Value ◽  
The Government ◽  
Health Organization

The communities within Binh Dinh province in the Central Vietnam are reliant on groundwater as their primary supply of domestic and potable water. Meanwhile, it is seriously contaminated with fluoride that causing fluorosis problem for people. This study aims to investigate the link between severity of dental fluorosis rate in a population and fluoride concentration in drinking water in Tay Son area. A total of 50 well-water samples were collected and 220 people were surveyed by questionnaire from 50 households at 3 villages: Tay Phu, Binh Tuong, Tay Giang of Tay Son district, Binh Dinh province, Vietnam. The quantitative assessment of severity of dental fluorosis was done by calculating the Community Fluorosis Index (CFI) using Dean’s classification. Result of this study showed that fluoride concentration in well-water varied from 0.31 mg/L to 7.69 mg/L (mean 2.66 mg/L, SD: 2.18 mg/L) with 70 % of well-water samples above the maximum permissible limit of 1.5 mg/L of World Health Organization (WHO) drinking water standard. 100 % people surveyed was suffered from dental fluorosis and Dean scale of dental fluorosis ranged from level 2 to level 5. CFI varied from 3.45 to 4.13 above limit value (0.6). The community seriously suffered from dental fluorosis. The fluoride concentrations and Dean Index have high correlation (r = 0.580, p < 0.0001). Based upon results of this study, it is recommended that the government should supply drinking water with appropriate fluoride content for this community.

scholarly journals Removal of ammonium from fish farms by biochar obtained from rice straw: Isotherm and kinetic studies for ammonium adsorption

2018 ◽  
Vol 36 (5-6) ◽  
pp. 1294-1309 ◽  
Author(s):  
Ahmed Khalil ◽  
Nikolai Sergeevich ◽  
Vita Borisova
Keyword(s):  
Rice Straw ◽  
Removal Efficiency ◽  
Kinetic Studies ◽  
Effect Of Temperature ◽  
Fish Farms ◽  
Isothermal Adsorption ◽  
Ammonium Adsorption ◽  
Pseudo Second Order ◽  
Water Pollutant ◽  
Physical And Chemical

Ammonium is a water pollutant that harms the environment, particularly fisheries. Rice straw is also an economic waste of rice, with millions of tons produced per year around the world. In this paper, physical and chemical procedures for the modification of rice straw were studied. The kinetic and isothermal adsorption trends were investigated, including the ammonium removal efficiency, the contact time of the adsorbent, the amount of adsorbent, and the initial concentration of NH4+. The effect of temperature and pH on the adsorption process was discussed. The removal efficiency of NH4+ recorded 43, 53.7, and 69.5%, with maximum adsorption values of 2.9, 3.5, and 4.5 mg/g at temperatures of 25 ± 5, 35 ± 5, and 45 ± 5°C, respectively, at pH 7.5. The biochar obtained from rice follows the pseudo-second-order equation for ammonium adsorption kinetics (R2 = 0.98). The adsorption isotherm follows Freundlich’s model (R2 = 0.99) and Langmuir’s model (R2 = 0.98).

scholarly journals An investigation on the efficiency of low-cost adsorbents in removing uranium from water samples

2020 ◽  
Vol 10 (10) ◽  
Author(s):  
Sandeep Police ◽  
Sukanta Maity ◽  
Dilip Kumar Chaudhary ◽  
Sanjay Kumar Sahu ◽  
A. Vinod Kumar
Keyword(s):  
Removal Efficiency ◽  
Low Cost ◽  
World Health ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Solution Ph ◽  
Sorption Data ◽  
Groundwater Samples ◽  
High Concentrations ◽  
Health Organization

Abstract The groundwater samples were found to be contaminated with high concentrations of uranium (U) in Punjab state as well as in few other locations of India. U being chemically toxic can deteriorate health when ingested. Hence, there is a need to remove U from contaminated water using an efficient, cheap and user friendly method. A study was initiated to investigate the efficiency of low-cost adsorbents in removing U from water. Seven adsorbents were screened for U removal efficiency, among which fly ash (FA) and tea waste (TW) were found to have better removal efficiency. Solid–liquid contact time and solution pH were optimized to establish conditions for better U removal efficiency. The U adsorption on FA and TW followed pseudo-second-order kinetics with rate constant values 4.63 g/mg/min and 15.63 g/mg/min, respectively. FA and TW had the highest U removal capability at pH 6 and pH 4, respectively. The U sorption data were fitted with Freundlich and Dubinin–Radushkevich isotherm models. The U adsorption on FA and TW is found to be a physical process with mean free energy (E) values less than 8 kJ/mol. Theoretically calculated maximum adsorption capacity values indicate that FA is a better adsorbent as compared to TW, which has been further confirmed experimentally. The U adsorption on both the adsorbents has interference from Ca2+ and no interference from Fe3+ at tested U concentrations. It is also found that FA and TW are effective in decontaminating U from spiked real groundwater samples to below the WHO (Guidelines for drinking water quality, 4th ed, vol 1, World Health Organization, Geneva, 2011) limit.

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