103 research outputs found
Effect of operating parameters and cleaning on the performance of ceramic membranes treating partially clarified sugar cane juice
The performance of ceramic membranes with pore sizes of 0.05 and 0.10 mm in purifying limed and partially clarified sugar cane juice was investigated under different operating conditions. From various operating conditions and strategies, switching off the permeate for 5 seconds for every 5 minutes (S5sT5 m) by an automated control valve provided higher flux. From the three pH experiments conducted on the 0.05 mm membrane, the best performance was observed at a pH of 7.5. Amongst the four fouling models tested, the cake filtration model fitted the performance of both membranes with higher accuracy at a transmembrane pressure of 0.5 bar. Filtering the cane juice through the membrane reduced the turbidity by 99.7%, color by 15%, and the starch concentration by 80% as well as increased the purity by 1.4%. The effective cleaning chemical composition from experimental results showed that 1% NaOH and 3000 ppm NaOCl solution performed the best but only for the experiments that were treating limed and partially clarified juice at pH 7.5.<br /
Removal of ametryn using membrane bioreactor process & its Influence on critical flux
Compared to the Conventional Activated Sludge Process (ASP), Membrane Bioreactors (MBRs) have
proven their superior performance in wastewater treatment and reuse during the past two decades. Further,
MBRs have wide array of applications such as the removal of nutrients, toxic and persistent organic pollutants
(POPs), which are impossible or difficult to remove using ASP. However, fouling of membrane is one of the
main drawbacks to the widespread application of MBR technology and Extra-cellular Polymeric Substances
(EPS) secreted by microbes are considered as one of the major foulants, which will reduce the flux (L/m2/h)
through the membrane. Critical flux is defined as the flux above which membrane cake or gel layer formation
due to deposition of EPS and other colloids on the membrane surface occurs. Thus, one of the operating
strategies to control the fouling of MBRs is to operate those systems below the critical flux (at Sub-Critical
flux). This paper discusses the critical flux results, which were obtained from short-term common flux step
method, for a lab-scale MBR system treating Ametryn. This study compares the critical flux values that were
obtained by operating the MBR system (consisting of a submerged Hollow-Fibre membrane with pore size of
0.4μm and effective area of 0.2m2) at different operating conditions and mixed liquor properties. This study
revealed that the critical flux values found after the introduction of Ametryn were significantly lower than those
of obtained before adding Ametryn to the synthetic wastewater. It was also revealed that the production of
carbohydrates (in SMP) is greater than proteins, subsequent to the introduction of Ametryn and this may have
influenced the membrane to foul more. It was also observed that a significant removal (40-60%) of Ametryn
from this MBR during the critical flux determination experiments with 40 minutes flux-step duration
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Evaluation of critical congenital heart defects screening using pulse oximetry in the neonatal intensive care unit.
ObjectiveTo evaluate the implementation of early screening for critical congenital heart defects (CCHDs) in the neonatal intensive care unit (NICU) and potential exclusion of sub-populations from universal screening.Study designProspective evaluation of CCHD screening at multiple time intervals was conducted in 21 NICUs across five states (n=4556 infants).ResultsOf the 4120 infants with complete screens, 92% did not have prenatal CHD diagnosis or echocardiography before screening, 72% were not receiving oxygen at 24 to 48 h and 56% were born ⩾2500 g. Thirty-seven infants failed screening (0.9%); none with an unsuspected CCHD. False positive rates were low for infants not receiving oxygen (0.5%) and those screened after weaning (0.6%), yet higher among infants born at <28 weeks (3.8%). Unnecessary echocardiograms were minimal (0.2%).ConclusionGiven the majority of NICU infants were ⩾2500 g, not on oxygen and not preidentified for CCHD, systematic screening at 24 to 48 h may be of benefit for early detection of CCHD with minimal burden
SARS Antibody Testing in Children: Development of Oral Fluid Assays for IgG Measurements.
Seroepidemiological studies to monitor antibody kinetics are important for assessing the extent and spread of SARS-CoV-2 in a population. Noninvasive sampling methods are advantageous for reducing the need for venipuncture, which may be a barrier to investigations, particularly in pediatric populations. Oral fluids are obtained by gingiva-crevicular sampling from children and adults and are very well accepted. Enzyme immunoassays (EIAs) based on these samples have acceptable sensitivity and specificity compared to conventional serum-based antibody EIAs and are suitable for population-based surveillance. We describe the development and evaluation of SARS-CoV-2 IgG EIAs using SARS-CoV-2 viral nucleoprotein (NP) and spike (S) proteins in IgG isotype capture format and an indirect receptor-binding-domain (RBD) IgG EIA, intended for use in children as a primary endpoint. All three assays were assessed using a panel of 1,999 paired serum and oral fluids from children and adults participating in school SARS-CoV-2 surveillance studies during and after the first and second pandemic wave in the United Kingdom. The anti-NP IgG capture assay was the best candidate, with an overall sensitivity of 75% (95% confidence interval [CI]: 71 to 79%) and specificity of 99% (95% CI: 78 to 99%) compared with paired serum antibodies. Sensitivity observed in children (80%, 95% CI: 71 to 88%) was higher than that in adults (67%, CI: 60% to 74%). Oral fluid assays (OF) using spike protein and RBD antigens were also 99% specific and achieved reasonable but lower sensitivity in the target population (78%, 95% CI [68% to 86%] and 53%, 95% CI [43% to 64%], respectively). IMPORTANCE We report on the first large-scale assessment of the suitability of oral fluids for detection of SARS-CoV-2 antibody obtained from healthy children attending school. The sample type (gingiva-crevicular fluid, which is a transudate of blood but is not saliva) can be self collected. Although detection of antibodies in oral fluids is less sensitive than that in blood, our study suggests an optimal format for operational use. The laboratory methods we have developed can reliably measure antibodies in children, who are able to take their own samples. Our findings are of immediate practical relevance for use in large-scale seroprevalence studies designed to measure exposure to infection, as they typically require venipuncture. Overall, our data indicate that OF assays based on the detection of SARS-CoV-2 antibodies are a tool suitable for population-based seroepidemiology studies in children and highly acceptable in children and adults, as venipuncture is no longer necessary
Effects of salinity build-up on the performance of an anaerobic membrane bioreactor regarding basic water quality parameters and removal of trace organic contaminants
Defining Terms Used for Animals Working in Support Roles for People with Support Needs
This is the final version. Available on open access from MDPI via the DOI in this recordData Availability Statement:
De-identified qualitative data can be made available by contacting the lead author.The nomenclature used to describe animals working in roles supporting people can be confusing. The same term may be used to describe different roles, or two terms may mean the same thing. This confusion is evident among researchers, practitioners, and end users. Because certain animal roles are provided with legal protections and/or government-funding support in some jurisdictions, it is necessary to clearly define the existing terms to avoid confusion. The aim of this paper is to provide operationalized definitions for nine terms, which would be useful in many world regions: "assistance animal", "companion animal", "educational/school support animal", "emotional support animal", "facility animal", "service animal", "skilled companion animal", "therapy animal", and "visiting/visitation animal". At the International Society for Anthrozoology (ISAZ) conferences in 2018 and 2020, over 100 delegates participated in workshops to define these terms, many of whom co-authored this paper. Through an iterative process, we have defined the nine terms and explained how they differ from each other. We recommend phasing out two terms (i.e., "skilled companion animal" and "service animal") due to overlap with other terms that could potentially exacerbate confusion. The implications for several regions of the world are discussed
Performance of a laboratory-scale membrane bioreactor consisting mixed liquor with aquatic worms under toxic conditions
A laboratory scale membrane bioreactor (MBR) consisting of worms was operated for 214 days. The objective was to evaluate the treatment and operating performance of the MBR with and without the addition of Ametryn which is a toxic and persistent herbicide. Removal of Ametryn was doubled (up to 80%) in the MBR when the worms were present. Increased rate (2.5 kPa/day) of trans-membrane pressure (TMP) and low concentration of MLSS (5.5 g/L) were recorded when the worm population was high (80-100 worms per 70 µL). Short-term critical flux values were increased from 7.5 to 15 and then to 30 L/m2/h when the worm numbers decreased from 90 to 35 and then to 18 per 70 μL of mixed liquor respectively. Further, high levels of carbohydrate concentration of soluble microbial products (SMP) and smaller sludge floc-sizes were found when the worm numbers were high
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