Independent University

Salman M.S., Sheikh M.C., Hasan M.M., Hasan M.N., Kubra K.T., Rehan A.I., Awual M.E., Rasee A.I., Waliullah R.M., Hossain M.S., Khaleque M.A., Alsukaibi A.K., Alshammari H.M., Awual M.R.

Dye wastewater has a severe influence on the natural water environment. Using materials functioned by adsorption to remove dyes has received much attention due it’s to its high decolorization or removal efficiency. The study aims to complement chitosan-treated cotton composite material for toxic dye removal from contaminated water to save human health. The work identifies and analyses the removal of reactive dye (Remazol Brilliant Red F3B (RR)) and proffers its high adsorption ability with chitosan-cotton composite. The dye removal parameter was performed based on the solution pH, contact time, initial concentration, competing for ion affinity, maximum adsorption capacity, and reuses with potential use. The solution pH was shown important parameter to RR dye uptake and a suitable pH of 7.0 was selected according to high adsorption ability. The competing ions were not adversely affected in the dye adsorption as expected of a stable bonding mechanism. The adsorption results were highly fitted with the Langmuir adsorption isotherm model and the maximum adsorption was 169.33 mg/g. The chitosan-cotton composite displayed high reusability based on the elution and simultaneous regeneration ability. The adsorbed RR dye was eluted using ethanol and reused for the next operation after washing with water without significant deterioration.

Waliullah R.M., Islam Rehan A., Eti Awual M., Islam Rasee A., Chanmiya Sheikh M., Shad Salman M., Sohrab Hossain M., Munjur Hasan M., Tul Kubra K., Nazmul Hasan M., Marwani H.M., Islam A., Rahman M.M., Abdul Khaleque M., Rabiul Awual M.

The prevalence of dyes in aquatic environments raises severe concerns on a global scale. Methyl orange (MO) is a typical anionic organic dye, which is widely used in industrial wastewater such as textile and paper making. Then the treatment of water contaminated with dyes is an important aspect. The recent decade has witnessed adsorption technology emerging as an advanced dye wastewater treatment with great potential and a grand blueprint, in which the specific surface area and active sites of the adsorbent are considered to be the two most important characteristics largely impacting the adsorption performance. In this study, chitosan-treated nanocomposite was prepared as an effective adsorbent for the removal of MO from contaminated water. The dye removal parameter was performed according to the solution acidity, reaction time, initial concentration, competing for ion affinity, maximum adsorption capacity, and reuse with potential use. The solution pH played a key role in MO dye removal and a suitable pH of 7.0 was selected according to high adsorption ability. The adsorption results were highly fitted with the Langmuir adsorption isotherm model and the maximum adsorption was 172.17 mg/g. The results revealed that introducing chitosan could improve the adsorption capacity and rate effectively even though sacrificing part of specific surface areas of the cotton, indicating that active sites might play a dominant role during the MO adsorption. In addition, the fabricated nanocomposite adsorbent was recycled rapidly by the eluent and regenerated simultaneously, which exhibited the advantages of easy operation as a potentially cost-effective material. The chitosan-based nanocomposite displayed high reusability based on the elution and simultaneous regeneration ability. Therefore, as a cheap green nanocomposite adsorbent with high adsorption performance for MO, chitosan-based fibrous nanocomposite adsorbent is expected to become one of the best candidate materials for future industrial wastewater treatment.

Awual M.R., Hasan M.N., Hasan M.M., Salman M.S., Sheikh M.C., Kubra K.T., Islam M.S., Marwani H.M., Islam A., Khaleque M.A., Waliullah R.M., Hossain M.S., Rasee A.I., Rehan A.I., Awual M.E.

The hybrid donor chemical ligand of 5-tert-butyl-2-hydroxybenzaldehyde thiosemicarbazone (THTB) was prepared and then embedded onto inorganic porous silica as hybrid conjugate materials (HCM). The Europium (Eu(III)) ion was selected from the lanthanides (Ln(III)) series for green and robust adsorption and recovery based on the adsorption, complexation, and selectivity tendency from the standpoint of the pH-dependent factor. The chemical compound of THTB consisted of O-, N-, and S-donor atoms and was able to make stable complexation with Ln(III) ions in optimum conditions due to the open functionality of the HCM. A surface complexation with a good complexation fitting to the experimentally collected data was used to describe the adsorption mechanism. The Eu(III) ion adsorption performance was measured with batch equilibrium methods. The affecting experimental protocols including solution pH, contact time, initial Eu(III) ion concentration, foreign ions effect, and recovery were carried out and evaluated consistently. The Eu(III) ion adsorption by the HCM was at pH 5.0 and this pH was selected to avoid the precipitation problem to ensure the adsorption mechanism. The co-existing several metal ions were not interfered with Eu(III) ion adsorption by the HCM due to the high affinity between Eu(III) ion and the functional groups of HCM. The bonding mechanism suggested that O-, N-, and S-donor atoms of THTB were strongly coordinated to Eu(III) with 2:1 ratio complexation. The Langmuir adsorption isotherm model was plotted due to the HCM morphology and applied to validate the adsorption isotherms according to the homogeneous ordered frameworks. The Eu(III) ion adsorption capacity by the HCM was 176.31 mg/g as expected because of the high surface area of the HCM. The adsorbed Eu(III) ion was completely eluted from HCM with the eluent of 0.20 M HNO3 and simultaneously regenerated into its initial form without significant deterioration. This study could be of great applicative utility for Eu(III) ions from waste aqueous solutions as green technology.

Hasan M.M., Salman M.S., Hasan M.N., Rehan A.I., Awual M.E., Rasee A.I., Waliullah R.M., Hossain M.S., Kubra K.T., Sheikh M.C., Khaleque M.A., Marwani H.M., Islam A., Awual M.R.

The chemical ligand-based conjugate adsorbent was prepared for selective and sensitive toxic lead (Pb(II)) ions monitoring and removal from contaminated water to save water quality and human health. Both in the monitoring and removal operations, the solution pH played a vital role by the conjugate adsorbent. The data clarified that pH 3.50 was suitable for simultaneous monitoring and removal of Pb(II) ions. In the monitoring, a significant color was formed upon the addition of Pb(II) ion even in the presence of ultra-trace level. Then the solution pH, reaction time, foreign ion, and initial concentration effect were systematically measured. The conjugate adsorbent exhibited an extremely low detection limit (0.35 µg/L) to comply with the material’s applicability in real sample onsite monitoring. In the reaction time effect, color optimization and high removal efficiency was achieved by increasing the reaction time. However, the diverse foreign ions were not adversely affected in the monitoring and removal to clarify the conjugate adsorbent as sensitive and selective towards the Pb(II) ions. The conjugate adsorbent was shown highly ordered structure and was able to open high functionality for Pb(II) ion monitoring and removal. The adsorption data also revealed that the present conjugate adsorbent exhibited adsorption capacity (172.87 mg/g) and was well fitted by the Langmuir adsorption isotherm with monolayer coverage. The adsorbed Pb(II) ion was desorbed using 0.30 M HCl and then simultaneously regenerated into the initial form for several cycles use after rinsing with water. Then it is expected that the optimum protocol effectively captured the Pb(II) in a sustainable and environmentally friendly manner for the production of clean water to safeguard public health and environmental remediation.

Kubra K.T., Hasan M.M., Hasan M.N., Salman M.S., Khaleque M.A., Sheikh M.C., Rehan A.I., Rasee A.I., Waliullah R.M., Awual M.E., Hossain M.S., Alsukaibi A.K., Alshammari H.M., Awual M.R.

The organic ligand of 3–(((5–ethoxybenzenethiol)imino)methyl)–salicylic acid (EBMS) was synthesized and then immobilized onto the mesoporous silica for the fabrication of facial composite adsorbent (FCA). The FCA was successfully utilized for the heavy lanthanide of Thulium(Tm(III)) separation, adsorption, and recovery in the solid-liquid approach. The FCA characterizations and affecting experimental parameters were assessed systematically. The Tm(III) ion was selected due to the high adsorption ability of the FCA according to the intra-series separation behaviors. The solution pH played a key role based on hydroxide formation in the basic pH region and a slightly acidic pH (3.50) was selected based on the high adsorption ability. The FCA was shown high kinetic performance and diverse competing metal ions did not interfere with Tm(III) adsorption. The Tm(III) adsorption was well-fitted with the Langmuir adsorption isotherm model with monolayer coverage and the maximum adsorption capacity was determined as 168.57 mg/g. The Tm(III) ion was strongly coordinated with the EBMS and the expected bond distance between Tm-N was shorter than the other bond length of Tm-S atoms in the complexation mechanism. The adsorbed Tm(III) ion was completely desorbed from the FCA with the suitable eluent of 0.25 M HNO3 and then simultaneously regenerated the FCA into the initial form without significant deterioration in the original functionality. The highest selectivity and maximum adsorption capacity of FCA to Tm(III) ions indicated that the proposed EBMS ligand-based composite adsorbent high potentiality to separate and recover the Tm(III) ions from waste samples effectively.

Walli-Attaei M., Joseph P., Rosengren A., Chow C.K., Rangarajan S., Lear S.A., AlHabib K.F., Davletov K., Dans A., Lanas F., Yeates K., Poirier P., Teo K.K., Bahonar A., Camilo F., et. al.

SummaryBackground Some studies, mainly from high-income countries (HICs), report that women receive less care (investigations and treatments) for cardiovascular disease than do men and might have a higher risk of death. However, very few studies systematically report risk factors, use of primary or secondary prevention medications, incidence of cardiovascular disease, or death in populations drawn from the community. Given that most cardiovascular disease occurs in low-income and middle-income countries (LMICs), there is a need for comprehensive information comparing treatments and outcomes between women and men in HICs, middle-income countries, and low-income countries from community-based population studies. Methods In the Prospective Urban Rural Epidemiological study (PURE), individuals aged 35–70 years from urban and rural communities in 27 countries were considered for inclusion. We recorded information on participants' sociodemographic characteristics, risk factors, medication use, cardiac investigations, and interventions. 168 490 participants who enrolled in the first two of the three phases of PURE were followed up prospectively for incident cardiovascular disease and death. Findings From Jan 6, 2005 to May 6, 2019, 202 072 individuals were recruited to the study. The mean age of women included in the study was 50·8 (SD 9·9) years compared with 51·7 (10) years for men. Participants were followed up for a median of 9·5 (IQR 8·5–10·9) years. Women had a lower cardiovascular disease risk factor burden using two different risk scores (INTERHEART and Framingham). Primary prevention strategies, such as adoption of several healthy lifestyle behaviours and use of proven medicines, were more frequent in women than men. Incidence of cardiovascular disease (4·1 [95% CI 4·0–4·2] for women vs 6·4 [6·2–6·6] for men per 1000 person-years; adjusted hazard ratio [aHR] 0·75 [95% CI 0·72–0·79]) and all-cause death (4·5 [95% CI 4·4–4·7] for women vs 7·4 [7·2–7·7] for men per 1000 person-years; aHR 0·62 [95% CI 0·60–0·65]) were also lower in women. By contrast, secondary prevention treatments, cardiac investigations, and coronary revascularisation were less frequent in women than men with coronary artery disease in all groups of countries. Despite this, women had lower risk of recurrent cardiovascular disease events (20·0 [95% CI 18·2–21·7] versus 27·7 [95% CI 25·6–29·8] per 1000 person-years in men, adjusted hazard ratio 0·73 [95% CI 0·64-0·83]) and women had lower 30-day mortality after a new cardiovascular disease event compared with men (22% in women versus 28% in men; p

Ahmed S.A., Ajisola M., Azeem K., Bakibinga P., Chen Y., Choudhury N.N., Fayehun O., Griffiths F., Harris B., Kibe P., Lilford R.J., Omigbodun A., Rizvi N., Sartori J., Smith S., et. al.

IntroductionWith COVID-19, there is urgency for policymakers to understand and respond to the health needs of slum communities. Lockdowns for pandemic control have health, social and economic consequences. We consider access to healthcare before and during COVID-19 with those working and living in slum communities.MethodsIn seven slums in Bangladesh, Kenya, Nigeria and Pakistan, we explored stakeholder perspectives and experiences of healthcare access for non-COVID-19 conditions in two periods: pre-COVID-19 and during COVID-19 lockdowns.ResultsBetween March 2018 and May 2020, we engaged with 860 community leaders, residents, health workers and local authority representatives. Perceived common illnesses in all sites included respiratory, gastric, waterborne and mosquitoborne illnesses and hypertension. Pre-COVID, stakeholders described various preventive, diagnostic and treatment services, including well-used antenatal and immunisation programmes and some screening for hypertension, tuberculosis, HIV and vectorborne disease. In all sites, pharmacists and patent medicine vendors were key providers of treatment and advice for minor illnesses. Mental health services and those addressing gender-based violence were perceived to be limited or unavailable. With COVID-19, a reduction in access to healthcare services was reported in all sites, including preventive services. Cost of healthcare increased while household income reduced. Residents had difficulty reaching healthcare facilities. Fear of being diagnosed with COVID-19 discouraged healthcare seeking. Alleviators included provision of healthcare by phone, pharmacists/drug vendors extending credit and residents receiving philanthropic or government support; these were inconsistent and inadequate.ConclusionSlum residents’ ability to seek healthcare for non-COVID-19 conditions has been reduced during lockdowns. To encourage healthcare seeking, clear communication is needed about what is available and whether infection control is in place. Policymakers need to ensure that costs do not escalate and unfairly disadvantage slum communities. Remote consulting to reduce face-to-face contact and provision of mental health and gender-based violence services should be considered.

Narula N., Wong E.C., Dehghan M., Mente A., Rangarajan S., Lanas F., Lopez-Jaramillo P., Rohatgi P., Lakshmi P.V., Varma R.P., Orlandini A., Avezum A., Wielgosz A., Poirier P., Almadi M.A., et. al.

Abstract Objective To evaluate the relation between intake of ultra-processed food and risk of inflammatory bowel disease (IBD). Design Prospective cohort study. Setting 21 low, middle, and high income countries across seven geographical regions (Europe and North America, South America, Africa, Middle East, south Asia, South East Asia, and China). Participants 116 087 adults aged 35-70 years with at least one cycle of follow-up and complete baseline food frequency questionnaire (FFQ) data (country specific validated FFQs were used to document baseline dietary intake). Participants were followed prospectively at least every three years. Main outcome measures The main outcome was development of IBD, including Crohn’s disease or ulcerative colitis. Associations between ultra-processed food intake and risk of IBD were assessed using Cox proportional hazard multivariable models. Results are presented as hazard ratios with 95% confidence intervals. Results Participants were enrolled in the study between 2003 and 2016. During the median follow-up of 9.7 years (interquartile range 8.9-11.2 years), 467 participants developed incident IBD (90 with Crohn’s disease and 377 with ulcerative colitis). After adjustment for potential confounding factors, higher intake of ultra-processed food was associated with a higher risk of incident IBD (hazard ratio 1.82, 95% confidence interval 1.22 to 2.72 for ≥5 servings/day and 1.67, 1.18 to 2.37 for 1-4 servings/day compared with <1 serving/day, P=0.006 for trend). Different subgroups of ultra-processed food, including soft drinks, refined sweetened foods, salty snacks, and processed meat, each were associated with higher hazard ratios for IBD. Results were consistent for Crohn’s disease and ulcerative colitis with low heterogeneity. Intakes of white meat, red meat, dairy, starch, and fruit, vegetables, and legumes were not associated with incident IBD. Conclusions Higher intake of ultra-processed food was positively associated with risk of IBD. Further studies are needed to identify the contributory factors within ultra-processed foods. Study registration ClinicalTrials.gov NCT03225586 .

Rehan A.I., Rasee A.I., Awual M.E., Waliullah R.M., Hossain M.S., Kubra K.T., Shad Salman M., Munjur Hasan M., Nazmul Hasan M., Chanmiya Sheikh M., Marwani H.M., Abdul Khaleque M., Islam A., Rabiul Awual M.

Materials with regulated nanoscale morphology provide capabilities to remove dangerous pollutants from wastewater, by adsorption. In this study, the chitosan-based composite fibrous adsorbent was fabricated and used as a novel and facile eliminator in the process of removing cationic methyl orange (MO) from the water medium. Different methods were applied to check the properties of the desired composite fibrous adsorbent. The removal value showed that the chitosan-embedded composite fibrous adsorbent has super characteristics and can be removed the organic dye from the water. The influence of pH, time, temperature, eliminator quantity, and MO content was explored. With increasing time and eliminator quantity, the adsorption efficiency increased. The composite fibrous adsorbent with the advantage of its high functionality and combined micro-nanomorphology features, has emerged as a very promising candidate for obtaining versatile and robust adsorbents. This work presents how the tunned synthesis of composite fibrous adsorbent tailored their nanoarchitecture giving rise to adsorption capacities toward cleaning aqueous samples polluted with MO dye. The composite fibrous adsorbent was prepared by the direct immobilization method, with normal aging temperature, in order to study the effect of synthesis conditions on the adsorption properties of MO dye. The solution acidity was exhibited as the key factor, and a suitable pH of 5.50 was selected based on the efficiency. The competing ions were not adversely affected in the dye adsorption as defined by the stable bonding mechanism. The adsorption data were highly fitted with the Langmuir adsorption model with monolayer coverage. The determined maximum adsorption was 175.45 mg/g, which was comparable with the other forms of materials. The adsorbed MO dye elution was evaluated using ethanol and then the composite fibrous adsorbent was ready to use for MO dye adsorption after washing with water without significant loss in its functionality. Therefore, we explored the tunned morphology of composite fibrous adsorbent for obtaining performant adsorbents for the elimination of refractory pollutants in wastewater.

Rasee A.I., Awual E., Rehan A.I., Hossain M.S., Waliullah R.M., Kubra K.T., Sheikh M.C., Salman M.S., Hasan M.N., Hasan M.M., Marwani H.M., Islam A., Khaleque M.A., Awual M.R.

The novel organic compound of ammonium (4-chlro-2-mercaptophenyl)carbamodithioate (ACMPC) was prepared and then subsequently grafted onto the mesoporous silica by direct approach for the preparation of composite adsorbent (CPA). The lanthanide (Ln(III)) intra-series separation behavior was measured using CPA and then the samarium (Sm(III)) ion was selected according to the high adsorption ability by CPA for effective separation, adsorption, and recovery in the solid-liquid approach. The mesoporous silica and CPA were characterized systematically for the evaluation of affecting experimental criterion. The solution acidity played an important factor as the alkaline pH area was avoided due to the hydroxide precipitation probability and pH 5.0 was selected for selective and effective Sm(III) ion separation and recovery. The data clarified that CPA exhibited high kinetic performances with high adsorption ability. The Sm(III) adsorption was highly fitted with the Langmuir adsorption isotherm model with monolayer coverage and the maximum adsorption capacity was determined as 155.13 mg/g. In addition, the diverse foreign ions were not reduced the Sm(III) ion adsorption significantly, and the CPA has approximately no adsorption capacity for other ions at this pH. The Sm(III) ion was strongly coordinated with the ACMPC and the expected highly stable complexation mechanism with the soft donor of N- and S- atoms. The elution of Sm(III) ions from the saturated CPA was desorbed successfully with 0.30 M HNO3. The regenerated CPA that remained maintained the high selectivity to Sm(III) ions and exhibited almost the same adsorption capacity as that of the original CPA. Therefore, the proposed CPA offered a cost-effective material and may be considered a viable alternative for effectively Sm(III) ion separation and recovery from waste samples as potential materials.