As(III) Removal by Dynamic Adsorption onto Amberlite XAD7 Functionalized with Crown Ether and Doped with Fe(III) Ions

2019 ◽  
Vol 70 (7) ◽  
pp. 2330-2334
Author(s):  
Mihaela Ciopec ◽  
Adina Negrea ◽  
Narcis Duteanu ◽  
Corneliu Mircea Davidescu ◽  
Iosif Hulka ◽  
...  
Keyword(s):  
Adsorption Process ◽  
Arsenic Removal ◽  
Arsenic Concentration ◽  
Fixed Bed ◽  
World Health ◽  
Arsenic Content ◽  
Arsenic Adsorption ◽  
Stage Of Development ◽  
Wide Range ◽  
Health Organization

Arsenic content in groundwater�s present a wide range of concentration, ranging from hundreds of micrograms to thousands of micrograms of arsenic per litter, while the maximum permitted arsenic concentration established by World Health Organization (WHO) is 10 mg L-1. According to the WHO all people, regardless of their stage of development and their social economic condition, have the right to have access to adequate drinking water. The most efficient and economic technique used for arsenic removal is represented by adsorption. In order to make this remediation technique more affordable and environmentally friendly is important to new materials with advance adsorbent properties. Novelty of present paper is represented by the usage of a new adsorbent material obtained by physical - chemical modification of Amberlite XAD polymers using crown ethers followed by iron doping, due to well-known affinity of arsenic for iron ions. Present paper aims to test the obtained modified Amberlite polymer for arsenic removal from real groundwater by using adsorption in a fixed bed column, establishing in this way a mechanism for the adsorption process. During experimental work was studied the influence of competing ions from real water into the arsenic adsorption process.

scholarly journals Adsorption of arsenic and phosphate from groundwater onto a calcined laterite as fixed bed in column experiments

2020 ◽  
Vol 8 (2) ◽  
pp. 227-243
Author(s):  
Yacouba Sanou ◽  
Raymond Kabore ◽  
Samuel Pare
Keyword(s):  
Arsenic Removal ◽  
Arsenic Concentration ◽  
Fixed Bed ◽  
Column Experiments ◽  
Arsenic Adsorption ◽  
Experimental Conditions ◽  
Ph Values ◽  
Naoh Solution ◽  
Removal Of Arsenic ◽  
Maximum Removal

This work was focused on laterite soil as adsorbent for the removal of arsenic and phosphate from groundwater using column experiments. Results revealed a decrease of arsenic removal efficiency from 100 to 79% with flow rate increasing. Maximum removal of 100% for arsenic and 85% for phosphates was obtained for pH values between 3.5 and 6. The increase of initial arsenic concentration and phosphate amount caused an increase of arsenic adsorption up to 24 µg/g while 58.5 µg/g for phosphate. NaOH solution could desorb 86.8% of arsenic and the reuse of regenerated laterite indicated its efficiency in same experimental conditions.

scholarly journals First step concerning improvement of arsenic removal by adapted Kanchan filters in the lowlands of Nepal

2020 ◽  
pp. 01-09 ◽  
Author(s):  
Barbara Mueller
Keyword(s):  
Drinking Water ◽  
Ground Water ◽  
Removal Efficiency ◽  
Arsenic Removal ◽  
Arsenic Concentration ◽  
Operating Conditions ◽  
World Health ◽  
Water Composition ◽  
Keywords Arsenic ◽  
Health Organization

In the Terai region of Nepal (the southern lowlands of the country) the arsenic concentration of extracted ground water used as drinking water frequently exceeds the actual World Health Organization (WHO) drinking water guideline concentration of 10 μg/L. Single household filters (so called Kanchan filters) are employed to eliminate as from the well water. Being assembled to remove as utilizing zero-valent (ZVI) media, their efficiency was observed to vary to a high degree depending on design, ground water composition and the current operating conditions. Based on these concerns three field campaigns were organized in order to test ground water composition and filter handling on spot. This report depicts for the first time the results of this screening regarding removal efficiencies and clearly disclose future adaptation of the design and enhancement of the Kanchan filters uniquely used in Nepal. Removal efficiency varied between 5.81 % to 97.1 % depending on material, usage and mode of operation. The measurements of improvement include the replacement of nails and sand regularly; increasing the contact time between ground water and nails; preventing the nails from drying in order to maintain oxidizing settings; proper and regularly repeated instructions of the users. Keywords: Arsenic; Kanchan filters; Removal efficiency

scholarly journals Point-of-Use Water Filtration for Arsenic: A Sustainable and Simple Solution in Resource-Poor Settings

2014 ◽  
Vol 9 (1) ◽  
pp. 79-91 ◽  
Author(s):  
Stephen D. Passman ◽  
Tyler J. White ◽  
Roger D. Lewis
Keyword(s):  
Drinking Water ◽  
Arsenic Removal ◽  
Arsenic Concentration ◽  
World Health ◽  
Coliform Bacteria ◽  
Bone Char ◽  
Water Filter ◽  
Point Of Use ◽  
Resource Poor ◽  
Health Organization

Lack of access to potable drinking water due to contamination from harmful metals is one of the most pressing public health issues globally. In areas close to mining and smelting operations, significant contamination from arsenic and other harmful metals can compound contamination from harmful microorganisms in drinking water. In response to this dual hazard, this study tests a prototype design of an improved point-of-use water filter for resource-poor areas and exposed populations. This project builds upon previous research that has demonstrated the effectiveness of clay pot filters impregnated with silver in reducing coliform bacteria. A compatible attachment comprised of activated charcoal in the form of bone char was added to the clay pot filter with the purpose of enabling the combined filter system to remove arsenic. The experiment tested the designed attachment with source water having an arsenic concentration of 500 parts per billion (ppb) to investigate the combined filter’s ability to reduce the arsenic to acceptable World Health Organization drinking water standards of 10 parts per billion or below. The results demonstrate a significant decrease in the arsenic concentration to below the 10 ppb standard with the bone char attachment, as well as a decrease in the arsenic concentration with the clay pot filter alone. These results warrant further investigation into the potential for clay pot filters with a charcoal layer to reduce arsenic concentrations in drinking water and demonstrate a potential additional benefit in arsenic removal by utilizing inexpensive bone char material in conjunction with the clay pot filter.

scholarly journals Evaluation of Fe-Mg Binary Oxide for As (III) Adsorption—Synthesis, Characterization and Kinetic Modelling

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 805
Author(s):  
Saif Ullah Khan ◽  
Rumman Zaidi ◽  
Feroz Shaik ◽  
Izharul Haq Farooqi ◽  
Ameer Azam ◽  
...  
Keyword(s):  
Arsenic Removal ◽  
Kinetic Modelling ◽  
Arsenic Concentration ◽  
Experimental Studies ◽  
Precipitation Method ◽  
Arsenic Adsorption ◽  
Adsorbent Dosage ◽  
X Ray ◽  
Co Precipitation ◽  
Contaminated Waters

Nanotechnology has received much attention in treating contaminated waters. In the present study, a facile co-precipitation method was employed to synthesize a novel iron and magnesium based binary metal oxide using a stoichiometrically fixed amount of FeNO3.9H2O and MgNO3.6H2O in a proportion of molar concentration 1:1 and was later evaluated in removing As (III) from contaminated waters. Characterization of the prepared nanomaterial was done using X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy Dispersive X-Ray Analysis (EDAX) and ultraviolet–visible spectrophotometry (UV-VIS). Experimental studies on batch scale were carried out, examining the effect of varying initial concentrations of metal, adsorbent dosage, application time and initial pH on removal efficiency. Arsenic removal increased on increasing adsorbent dosage (0.1–1 g/L) but trend reversed on increasing initial arsenic concentration attaining qmax of 263.20 mg/g. Adsorption was quite efficient in pH range 4–8. Freundlich fitted better for adsorption isotherm along with following Pseudo-2nd order kinetics. The reusability and effect of co-existing ions on arsenic adsorption, namely SO42−, CO32− and PO43− were also explored with reusability in 1st and 2nd cycles attained adsorptive removal up to 77% and 64% respectively. The prepared nano-adsorbent showed promising results in terms of high arsenic uptake (qmax of 263.20 mg/g) along with facile and cost-effective synthesis. Thus, the co-precipitation technique used in this work is a simple one step procedure without any use of any precursor as compared to most of the other procedures used for synthesis.

scholarly journals The Search for Natural and Synthetic Inhibitors That Would Complement Antivenoms as Therapeutics for Snakebite Envenoming

Toxins ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 451
Author(s):  
José María Gutiérrez ◽  
Laura-Oana Albulescu ◽  
Rachel H. Clare ◽  
Nicholas R. Casewell ◽  
Tarek Mohamed Abd Abd El-Aziz ◽  
...  
Keyword(s):  
Snake Venom ◽  
Serine Proteinase ◽  
Global Strategy ◽  
World Health ◽  
Wide Range ◽  
Variable Chemical ◽  
Snake Venom Metalloproteinase ◽  
Health Organization ◽  
The Impact ◽  
Natural And Synthetic

A global strategy, under the coordination of the World Health Organization, is being unfolded to reduce the impact of snakebite envenoming. One of the pillars of this strategy is to ensure safe and effective treatments. The mainstay in the therapy of snakebite envenoming is the administration of animal-derived antivenoms. In addition, new therapeutic options are being explored, including recombinant antibodies and natural and synthetic toxin inhibitors. In this review, snake venom toxins are classified in terms of their abundance and toxicity, and priority actions are being proposed in the search for snake venom metalloproteinase (SVMP), phospholipase A2 (PLA2), three-finger toxin (3FTx), and serine proteinase (SVSP) inhibitors. Natural inhibitors include compounds isolated from plants, animal sera, and mast cells, whereas synthetic inhibitors comprise a wide range of molecules of a variable chemical nature. Some of the most promising inhibitors, especially SVMP and PLA2 inhibitors, have been developed for other diseases and are being repurposed for snakebite envenoming. In addition, the search for drugs aimed at controlling endogenous processes generated in the course of envenoming is being pursued. The present review summarizes some of the most promising developments in this field and discusses issues that need to be considered for the effective translation of this knowledge to improve therapies for tackling snakebite envenoming.

scholarly journals Bleeding risks are higher in children versus adults given prophylactic platelet transfusions for treatment-induced hypoproliferative thrombocytopenia

Blood ◽  
2012 ◽  
Vol 120 (4) ◽  
pp. 748-760 ◽  
Author(s):  
Cassandra D. Josephson ◽  
Suzanne Granger ◽  
Susan F. Assmann ◽  
Marta-Inés Castillejo ◽  
Ronald G. Strauss ◽  
...  
Keyword(s):  
Bleeding Risk ◽  
World Health ◽  
Age Group ◽  
Transplant Recipients ◽  
Disease Treatment ◽  
Platelet Counts ◽  
Wide Range ◽  
Treatment Category ◽  
Dose Trial ◽  
Health Organization

Age-group analyses were conducted of patients in the prophylactic platelet dose trial (PLADO), which evaluated the relation between platelet dose per transfusion and bleeding. Hospitalized patients with treatment-induced hypoproliferative thrombocytopenia were randomly assigned to 1 of 3 platelet doses: 1.1 × 1011, 2.2 × 1011, or 4.4 × 1011 platelets/m2 per transfusion, given for morning counts of ≤ 10 000 platelets/μL. Daily hemostatic assessments were performed. The primary end point (percentage of patients who developed grade 2 or higher World Health Organization bleeding) was evaluated in 198 children (0-18 years) and 1044 adults. Although platelet dose did not predict bleeding for any age group, children overall had a significantly higher risk of grade 2 or higher bleeding than adults (86%, 88%, 77% vs 67% of patients aged 0-5 years, 6-12 years, 13-18 years, vs adults, respectively) and more days with grade 2 or higher bleeding (median, 3 days in each pediatric group vs 1 day in adults; P < .001). The effect of age on bleeding differed by disease treatment category and was most pronounced among autologous transplant recipients. Pediatric subjects were at higher risk of bleeding over a wide range of platelet counts, indicating that their excess bleeding risk may be because of factors other than platelet counts. This trial was registered at www.clinicaltrials.gov as #NCT00128713.

The impact of SARS-Cov-2 on the Nervous system and Mental Health

2021 ◽  
Vol 19 ◽  
Author(s):  
Mohamed Said Boulkrane ◽  
Victoria Ilina ◽  
Roman Melchakov ◽  
Mikhail Arisov ◽  
Julia Fedotova ◽  
...  
Keyword(s):  
Mental Health ◽  
Respiratory Illness ◽  
World Health ◽  
Current Review ◽  
Wide Range ◽  
Serious Disease ◽  
Health Organization ◽  
The Impact ◽  
The Brain ◽  
Severe Acute Respiratory Illness

: The World Health Organization declared the pandemic situation caused by SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2) in March 2020, but the detailed pathophysiological mechanisms of Coronavirus disease 2019 (COVID-19) are not yet completely understood. Therefore, to date, few therapeutic options are available for patients with mild-moderate or serious disease. In addition to systemic and respiratory symptoms, several reports have documented various neurological symptoms and impairments of mental health. The current review aims to provide the available evidence about the effects of SARS-CoV-2 infection on mental health. The present data suggest that SARS-CoV-2 produces a wide range of impairments and disorders of the brain. However, a limited number of studies investigated the neuroinvasive potential of SARS-CoV-2. Although the main features and outcomes of COVID-19 are linked to severe acute respiratory illness. The possible damages on the brain should be considered, too.

scholarly journals The WHO European health for all database

2003 ◽  
Vol 7 (6) ◽  
Author(s):  
Keyword(s):  
World Health ◽  
Health Statistics ◽  
Regional Office ◽  
International Context ◽  
Health Trends ◽  
Wide Range ◽  
The World ◽  
European Health ◽  
Health Organization ◽  
Health Situation

The European health for all database provides easy and rapid access to a wide range of basic health statistics (indicators) for the 51 Member States of the World Health Organization (WHO) European Region. It was developed by the WHO Regional Office for Europe in the mid 1980s to support the monitoring of health trends in the Region. The database is a helpful tool for international comparison and for assessing the health situation and trends in any European country in an international context.

scholarly journals Rehabilitation Machine for Bariatric Individuals

Machines ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 45
Author(s):  
Andrea Botta ◽  
Paride Cavallone ◽  
Luca Carbonari ◽  
Carmen Visconte ◽  
Giuseppe Quaglia
Keyword(s):  
Muscle Tone ◽  
Physical Exertion ◽  
World Health ◽  
Upper Body ◽  
Obese People ◽  
Leg Extension ◽  
Extension Mechanism ◽  
Physical Exercises ◽  
Wide Range ◽  
Health Organization

Obesity is known to be growing worldwide. The World Health Organization (WHO) reports that obesity has tripled since 1975. In 2016, 39% of adults over 18 years old were overweight, and 13% were obese. Obesity is mostly preventable by adopting lifestyle improvements, enhancing diet quality, and doing physical exercise. The workload of the physical exercises should be proportionate to the patient’s capabilities. However, it must be considered that obese people are not used to training; they may not endure physical exertion and, even more critically, they could have some psychological impediments to the workouts. Physical exercises and equipment must, therefore, guarantee comfort and prevent situations in which the bariatric individual may feel inadequate. For these reasons, this study aims to design an innovative system to approach simple physical activities, like leg and arm exercises, to bariatric users to enable them to recover mobility and muscle tone gradually. The leading feature of this architecture is the design of hidden exercise mechanisms to overcome the psychological barriers of the users toward these kinds of machines. This paper proposes the initial design of the main sub-systems composing the rehabilitation machine, namely the leg curl and leg extension mechanism and its control architecture, the upper body exercises system, and a series of regulation mechanisms required to accommodate a wide range of users. The proposed functional design will then lead to the development of a prototype to validate the machine.

scholarly journals The postcoital test in the development of new vaginal contraceptives†

2020 ◽  
Vol 103 (2) ◽  
pp. 437-444
Author(s):  
Christine K Mauck ◽  
Kathleen L Vincent
Keyword(s):  
Ease Of Use ◽  
World Health ◽  
Phase Ii Trials ◽  
High Power Field ◽  
Test Product ◽  
Efficacy Trials ◽  
Contraceptive Effectiveness ◽  
Wide Range ◽  
Definition Of ◽  
Health Organization

Abstract Postcoital tests (PCTs) have been used for over a century in the clinical evaluation of infertile couples, and for nearly 70 years in the evaluation of new vaginal contraceptive products. PCTs have been largely replaced by more modern methods in the study of infertility, but they remain the most useful way to obtain preliminary data on the effectiveness of vaginal contraceptive products. The World Health Organization has described important aspects of the procedure. It involves collection of cervical mucus at a certain time point after intercourse and the counting and characterization of sperm found in the mucus. A wide range of progressively motile sperm (PMS) has been associated with pregnancy rates in infertility studies. Eligibility for contraceptive trials includes the requirement that couples achieve a certain threshold number of PMS per high power field at midcycle in a baseline cycle without the test product. The primary endpoint, or definition of a satisfactory result in test cycles, is predefined. A literature review identified 10 PCT studies of vaginal contraceptives involving nine test products. Phase II trials of vaginal contraceptives have not been deemed feasible in the development of any vaginal contraceptive to date. A PCT study of a test product can be predictive of contraceptive efficacy, although ultimate contraceptive effectiveness is influenced by the ease of use of the product, along with patient compliance. PCT results similar to results seen with products that later showed satisfactory performance in efficacy trials is the best indicator of likely success of a test product.

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