501 research outputs found
Feasibility of iron loaded 'okara' for biosorption of phosphorous in aqueous solutions
This study investigated the feasibility of using soybean milk by-products (okara) as a sustainable biosorbent for phosphate removal in water and wastewater. The results show that raw okara could hardly decontaminate phosphate from aqueous solutions. Hence, in this work, okara was modified by being cationized using FeCl3 0.25M (namely iron loaded okara, ILO) to enhance the phosphorus adsorption capacity. The phosphate sorption onto ILO was well achieved under the conditions of pH 3, initial phosphorous concentration of 25mg/L, biosorbent dose of 20mg/L and contact time of 7h. Based on Langmuir model, the maximum adsorption capacity of phosphate by ILO was 4.785mg/g. The effects of interfering anions were in the order of CO32->SO42->NO3 It was also observed that Fe(III) was detached during operation. This problem can hinder the sustainable usability of ILO. Thus, further research would be necessary for improving the modification method. © 2013 Elsevier Ltd
Anaerobic membrane bioreactors for future green bioprocesses
© 2016 American Society of Civil Engineers. This chapter focuses on the comprehensive overview of the recent progress in anaerobic membrane bioreactor (AnMBR) applications, including the fundamental aspects and development of AnMBR processes. For a future green bioprocess, the chapter discusses the application development of AnMBRs in domestic and industrial wastewater treatment, opportunities for biogas production and waste minimization and membrane fouling researches. The anaerobic treatment processes are known to have the inherent advantages over the aerobic counterparts, such as sludge minimization and energy savings. The key competitive advantages of AnMBRs over conventional aerobic and anaerobic processes include total biomass retention, excellent effluent quality, bioenergy recovery, smaller footprint, lower energy consumption, high efficiency of wastewater treatment, and strong ability of handling fluctuation in influent quality. Biogas recovery represents one of the key green features of AnMBR technology, particularly for submerged AnMBR (SAnMBR). The compact configure of SAnMBR allows for more convenient collection of biogas
Development and evaluation of a new multi-metal binding biosorbent
A novel multi-metal binding biosorbent (MMBB) was developed by combining a group of three from the selective natural lignocellulosic agro-industrial wastes for effectively eliminating lead, cadmium, copper and zinc from aqueous solutions. Four MMBBs with different combinations (MMBB1: tea waste, corncob, sugarcane bagasse; MMBB2: tea waste, corncob and sawdust; MMBB3: tea waste, corncob and apple peel; MMBB4: tea waste, corncob and grape stalk) were evaluated. FTIR analysis for characterizing the MMBB2 explored that the MMBB2 contains more functional groups available for multi-metals binding. Comparing among the MMBBs as well as the single group biosorbents, MMBB2 was the best biosorbent with the maximum biosorption capacities of 41.48, 39.48, 94.00 and 27.23mg/g for Cd(II), Cu(II), Pb(II) and Zn(II), respectively. After 5 times of desorption with CaCl2, CH3COOH and NaCl as eluent, the MMBB2 still remained excellent biosorptive capacity, so as it could be well regenerated for reuse and possible recovery of metals. © 2013 Elsevier Ltd
Typical lignocellulosic wastes and by-products for biosorption process in water and wastewater treatment: A critical review
Biosorption on lignocellulosic wastes and by-products has been identified as a proper alternative to the existing technologies applied for toxic metal ion and dye removal from wastewater streams. This paper deals with utilization of typical low cost wastes and by-products produced in different food agricultural and agro-industries as biosorbent and reviews the current state of studies on a wide variety of cheap biosorbents in natural and modified forms. The efficiency of each biosorbent has been also discussed with respect to the operating conditions (e.g. temperature, hydraulic residence time, initial metal concentration, biosorbent particle size and its dosage), chemical modification on sorption capacity and preparation methods, as well as thermodynamics and kinetics. © 2013 Elsevier Ltd
Challenges in biogas production from anaerobic membrane bioreactors
© 2016 Spectacular applications of anaerobic membrane bioreactors (AnMBRs) are emerging due to the membrane enhanced biogas production in the form of renewable bioresources. They produce similar energy derived from the world's depleting natural fossil energy sources while minimizing greenhouse gas (GHG) emissions. During the last decade, many types of AnMBRs have been developed and applied so as to make biogas technology practical and economically viable. Referring to both conventional and advanced configurations, this review presents a comprehensive summary of AnMBRs for biogas production in recent years. The potential of biogas production from AnMBRs cannot be fully exploited, since certain constraints still remain and these cause low methane yield. This paper addresses a detailed assessment on the potential challenges that AnMBRs are encountering, with a major focus on many inhibitory substances and operational dilemmas. The aim is to provide a solid platform for advances in novel AnMBRs applications for optimized biogas production
Early-life activities mediate the association between family socioeconomic status in early childhood and physical fitness in early adolescence
The graded association between family socioeconomic status (SES) and physical fitness is evident, but little is known about the mechanism underlying this association. This study investigated the role of early-life activities as mediators of the longitudinal relationship between early-life SES and health-related physical fitness in 168 adolescents (51.2% boys; final mean age: 12.4 years old). In Wave 1 (2011–12), their parents completed questionnaires about family socioeconomic status (SES), parent–child activities, and child screen time. In Wave 2 (2014–15), participants’ physical activity levels were assessed through parent proxy-reports. In Wave 3 (2018–19), a direct assessment of handgrip strength, standing long-jump, and 6-min walk test (6MWT) performance was conducted. After controlling for demographic factors, results of mediation analyses revealed that (a) Wave 1 SES predicted Wave 3 long-jump and 6MWT performance; (b) child physical activity level in Wave 2 mediated the relation between Wave 1 SES and standing long-jump performance in Wave 3; and (c) recreational parent–child activities and child screen time in wave 1 mediated the relation between Wave 1 SES and 6MWT performance in Wave 3. Our findings suggest that the type and frequency of early-life activities play a role in the graded association between childhood SES and physical fitness in adolescence
Influence of Maternal Infection and Pregnancy Complications on Cord Blood Telomere Length
BACKGROUND: Exposure to suboptimal intrauterine environment might induce structural and functional changes that can affect neonatal health. Telomere length as an important indicator of cellular health has been associated with increased risk for disease development. OBJECTIVES: This study was aimed to examine the independent and combined effects of maternal, obstetric, and foetal factors on cord blood telomere length (TL). METHODS: Pregnant women at the gestational age of 20th to 24th week who attended the antenatal clinic of a major local hospital in Hong Kong were recruited. Participants were asked to complete a questionnaire on demographics, health-related quality of life, and history of risk behaviors. Medical history including pregnancy complications and neonatal outcomes was obtained from electronic medical records of both mother and neonate. Umbilical cord blood was collected at delivery for TL determination. RESULTS: A total of 753 pregnant women (average age: 32:18 ± 4:51 years) were recruited. The prevalence of maternal infection, anaemia, and hypertension
during pregnancy was 30.8%, 30.0%, and 6.0%, respectively. The adjusted regression model displayed that maternal
infection was negatively associated with cord blood TL (β = −0:18, p = 0:026). This association became even stronger in the
presence of antenatal anaemia, hypertension, delivery complications, or neonatal jaundice (β = −0:25 to −0.45). Conclusions.
This study consolidates evidence on the impact of adverse intrauterine environment at the cellular level. Maternal infection
was significantly associated with shorter cord blood TL in a unique manner such that its presence may critically determine
the susceptibility of telomere to other factors
Mental health & maltreatment risk of children with special educational needs during COVID-19
BACKGROUND: Children with special educational needs (SEN) are more vulnerable during the COVID-19 pandemic with risk of poor mental wellbeing and child maltreatment. OBJECTIVE: To examine the impact of COVID-19 on the mental health of children with SEN and their maltreatment risk. PARTICIPANTS AND SETTING: 417 children with SEN studying at special schools and 25,427 children with typical development (TD) studying at mainstream schools completed an online survey in April 2020 in Hong Kong during school closures due to COVID-19. METHOD: Emotional/behavioural difficulties, quality of life and parental stress of children with SEN were compared with typically developed children using mixed effect model. Linear regression analyses were performed to explore factors associated with child emotional/behavioural difficulties and parental stress during the pandemic. Chi-square test was performed to detect the differences in maltreatment risk before and during COVID-19. RESULTS: Children with SEN had significantly poorer overall quality of life (68.05 vs 80.65, p < 0.01). 23.5% of children had at least one episode of severe physical assault and 1.9% experienced very severe physical assault during COVID-19. Rates of physical assault increased significantly (59.8% vs. 71.2% p < 0.001) while children with mental disorders had increased risk of severe physical assault comparing to those without mental disorders (RR = 1.58, ꭓ2 = 5.19 p = 0.023). CONCLUSION: Children with SEN had poorer mental health than typically developed children during the COVID-19 pandemic. Maltreatment risk for children with SEN is higher in comparison to pre-COVID-19 era. Surveillance of child maltreatment, continuity of medical and rehabilitation care to support children with SEN are essential during a disease pandemic
Genome wide association mapping of grain arsenic, copper, molybdenum and zinc in rice (Oryza sativa L.) grown at four international field sites
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