24-hour Samples Research Articles

Reduction and discharge of SARS-CoV-2 RNA in Chicago-area water reclamation plants.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA is commonly excreted in the feces and urine of infected individuals and is, therefore, detected in wastewaters where infection is present in the surrounding population. Water reclamation plants (WRPs) that treat these wastewaters commonly discharge treated effluents into the surrounding environment, yet little is known about the removal or persistence of SARS-CoV-2 RNA through wastewater treatment systems and potential for eventual release into the environment. We collected 361 24-hour composite influent and effluent samples from seven WRPs in the Greater Chicago Area in Illinois. Samples were collected over a period of 21 weeks for three large WRPs (with design max flows of 1.89-2.32 billion gallons per day and serving a combined population of 4.62 million people) and 11 weeks for four smaller WRPs (with design max flows of 96.3-186 million gallons per day and serving a combined population of >0.5 million people). A total of two of the larger WRPs implemented seasonal disinfection (using UV light or chlorination/dechlorination) for 8 weeks of this sampling period. SARS-CoV-2 RNA was quantified in the influent and effluent samples by reverse-transcription quantitative PCR (RT-qPCR) of the N1 and N2 targets of the nucleocapsid (N) gene. Although SARS-CoV-2 RNA was regularly detected in influent and effluent from all WRPs, viral RNA concentrations in the effluent samples were considerably lower, with mean effluent: influent gene copy concentration ratios ranging from 1:160 to 1:2.95 between WRPs. Samples collected while disinfection was active vs. inactive did not show any significant difference in the portion of RNA persisting through the treatment process (P >.05).

Relative bioavailability study of a generic effervescent tablet formulation of dexketoprofen and thiocolchicoside versus the originator 25 mg film coated tablet (dexketoprofen) and 8 mg capsule (thiocolchicoside)

Aims: The aim of this study was to evaluate the pharmacokinetic profiles and the relative bioavailability of dexketoprofen and thiocolchicoside of the test preparation (dexketoprofen / thiocolchicoside 25 mg / 8 mg effervescent tablet) in comparison with the reference preparations (Keral 25 mg film coated tablet, containing dexketoprofen trometamol equivalent to 25 mg dexketoprofen (Menarini International Operations Luxembourg S.A.) (R1) and Muscoril 8 mg capsule, containing 8 mg thiocolchicoside (Sanofi Aventis İlaçları Ltd. Şti.) (R2) under fasting conditions. Methods: 25 healthy male subjects were enrolled in the study. Volunteers were hospitalised from the evening before drug administration (Day 0) until after the 24-hour blood sampling time on Day 2. Results: 24 subjects completed the study. Relative bioavailability (AUCT/AUCR1) of dexketoprofen from the test preparation was 100.99 %; (AUCT/AUCR2) of 3-O-glucuronide of thiocolchicoside (aglycone) from the test preparation was 100.47 %; (Cmax,T/Cmax,R1) of dexketoprofen from the test preparation was 122.59 %; (Cmax,T/Cmax,R2) of 3-O-glucuronide of thiocolchicoside (aglycone) from the test preparation was 111.43 %. Conclusions: The relative bioavailability AUCT /AUCR of the test preparation compared with both reference preparations is comparable, as shown by the geometric mean ratios of 100.59 % (dexketoprofen) and of 98.20 % (3-O-glucuronide of thiocolchicoside (aglycone).

Comparative Evaluation of Quantitative Protein Measurement of 12-Hour and 24-hour Urine Sample for the Diagnosis of Nephrotic Syndrome and their Correlation with Spot Urinary Protein Creatinine Ratio

Background: The amount of protein excretion is a reflection of disease activity in Nephrotic Syndrome. 24-hour urine collection has remained as the method of choice to quantify proteinuria. An alternative method for quantitative evaluation of proteinuria is measuring the ratio of protein or albumin to creatinine in an untimed ‘‘spot’’ urine specimen.
 Objective: To compare 12-hour versus 24-hour proteinuria in nephrotic syndrome and its correlation to spot urinary protein creatinine ratio.
 Materials & Methods: A comparative cross-sectional study was conducted in the Department of Pediatrics, Sir Salimullah Medical College Mitford Hospital (SSMC & MH), Dhaka over a period from September 2016 to June 2017. All the babies developing 1st attack of Nephrotic Syndrome and meeting the clinical criteria were included in the study. Complete history was taken from accompanying attendants. Thorough clinical examinations and relevant laboratory investigations (12- hour day urinary protein, 12-hour night urinary protein, 24-hour urinary total protein, S. Albumin, S. Cholesterol, Urinary spot Protein Creatinine ratio) were done. All the information was recorded in the fixed protocol. Collected data were classified, edited, coded and entered into computer for statistical analyses.
 Results: Out of 50 cases, the mean age was found 58.3±29.0 months. 12-hour day urinary protein was found 2.02±0.167 gm/m2/12 hours, mean; 12-hour night urinary protein was found 2.12±2.18 gm/m2/12 hours, mean; 24-hour urinary total protein was found 4.10±3.32 gm/m2/24 hours. The mean spot urinary protein creatinine ratio was found 12.58±7.21 with range from 2.02 to 29.85. There was no statistically significant difference between 12- hour day sample and 12-hour night sample. There was also no significant difference between 12-hour day & night sample with 24-hour sample. Results of all 03 samples were comparable to urinary protein creatinine ratio.
 Conclusion: This study reveals no statistically significant difference in quantitative estimation of 12-hour day and night protein with 24-hour urinary total protein. The 12- hour day and night protein and urinary total protein were comparable with each other and also with urinary spot protein creatinine ratio.So 12-hour day or night urinary total protein may be a diagnostic tool for nephrotic syndrome.
 Sir Salimullah Med Coll J 2021; 29(2): 105-111

Performance Upgrading Evaluation of the Anaerobic Baffled Reactor by Integrating Aerobic Media Filter for Municipal Wastewater Treatment

Background & Aims of the Study: Anaerobic baffled reactor (ABR) is one of the low-cost wastewater treatment systems; however, it has some limitations, such as insufficient standard nutrient outflow. Accordingly, it should be studied and developed. This research aims to determine the efficiency of a five-sectional reactor pilot and to upgrade it with an integrated aerated media filter in the reactor (integrated reactor) for municipal wastewater treatment. Materials and Methods: This study was performed on a laboratory scale with field conditions in the Khoy City wastewater treatment plant. The ABR reactor operated for 270 days with a hydraulic retention time (HRT) of 48, 36, 24, and 18 hours, respectively. The Integrated anaerobic baffled reactor (IABR) was operated for 35 days with 24 hours of HRT, i.e., aeration time of 5 hours. The reactors were fed in line from the inflowing wastewater to the treatment plant. A 24-hour combined sampling was performed 224 times from the inflow and outflow of the system, and volatile suspended solids, total kjeldahl nitrogen (TKN), total phosphorus (TP), biochemical oxygen demand (BOD), chemical oxygen demand (COD), and Total Suspended Solids (TSS) parameters were measured and compared with the effluent disposal standard. Results: The launch of ABR lasted 105 days, and its helpful operation lasted 200 days. In 18 to 48 hours, the reactor removed 79% to 91% of COD, 9% to 20% of TKN, 19% to 30% of phosphorus, and 89% to 94% of TSS. The IABR reached the effluent disposal standard in terms of TSS, BOD, COD, and phosphorus under 24 hours HRT, i.e., aeration time of 5 hours, and increased the COD removal efficiency by 6% compared to ABR under 24 hours HRT and the same conditions. Conclusion: By integrating the final aerobic media filter in ABR while reducing the required HRT by 50%, its efficiency in achieving the effluent disposal standards increased compared to ABR. Therefore, this system can be used to treat municipal wastewater.

Effect of Calcination Time on the Microstructure and Optical Properties of (Zn<sub>0.5</sub>Cu<sub>0.5</sub>)Al<sub>2</sub>O<sub>4</sub> Spinel Color Pigments

The (Zn0.5Cu0.5)Al2O4 pigments were synthesized by solid state processing with an aim to examine the kinetics of phase formation. The calcining temperature was 1100 °C with firing times of 2, 12, 24, 48 and 96 hours during which intermediate grinding was carried out. All five obtained pigment samples appeared to be single-phase as probed by XRD. However, lattice refinement revealed differences in the lattice constant which kept decreasing and reached constancy after 24 hours of firing. Such reduction in the lattice constant was associated with incorporation of smaller copper cations into the Zn-sites. FTIR spectra also supported this result as the relevant peaks still got broadened and shifted for the calcination times of less than 48 hours. Elemental analysis of the 2-hour sample showed small presence of starting precursor particles, though not detected by XRD, suggesting an incomplete reactivity at a minute scale. These structural changes were resultantly reflected by small but significant alterations in the color parameters. A higher degree of solid solution for the samples fired for longer times, as judged by lowering in the lattice constant, resulted in detectable changes in both a and b parameters. Longer calcination times yielded a brighter (higher L values) brownish tone likely due to both diminution in the averaged particle size from pulverizing and completion of solid solution. The first would be useful for good dispersion in glazes whereas the latter could be directly related to the degree of cationic substitution, confirming the expected “true” color for this specific doping level at a particular calcination temperature.

Coordination of SARS-CoV-2 wastewater and clinical testing of university students demonstrates the importance of sampling duration and collection time

Wastewater surveillance has been a useful tool complementing clinical testing during the COVID-19 pandemic. However, transitioning surveillance approaches to small populations, such as dormitories and assisted living facilities poses challenges including difficulties with sample collection and processing. Recently, the need for reliable and timely data has coincided with the need for precise local forecasting of the trajectory of COVID-19. This study compared wastewater and clinical data from the University of Delaware (Fall 2020 and Spring 2021 semesters), and evaluated wastewater collection practices for enhanced virus detection sensitivity. Fecal shedding of SARS-CoV-2 is known to occur in infected individuals. However, shedding concentrations and duration has been shown to vary. Therefore, three shedding periods (14, 21, and 30 days) were presumed and included for analysis of wastewater data. SARS-CoV-2 levels detected in wastewater correlated with clinical virus detection when a positive clinical test result was preceded by fecal shedding of 21 days (p< 0.05) and 30 days (p < 0.05), but not with new cases (p = 0.09) or 14 days of shedding (p = 0.17).Discretely collected wastewater samples were compared with 24-hour composite samples collected at the same site. The discrete samples (n = 99) were composited examining the influence of sampling duration and time of day on SARS-CoV-2 detection. SARS-CoV-2 detection varied among dormitory complexes and sampling durations of 3-hour, 12-hour, and 24-hour (controls). Collection times frequently showing high detection values were between the hours of 03:00 to 05:00 and 23:00 to 08:00. In each of these times of day 33% of samples (3/9) were significantly higher (p < 0.05) than the control sample. The remainder (6/9) of the collection times (3-hour and 12-hour) were not different (p > 0.05) from the control. This study provides additional framework for continued methodology development for microbiological wastewater surveillance as the COVID-19 pandemic progresses and in preparation for future epidemiological efforts.

Diagnosis of gestational diabetes: Are five rounds of blood sampling necessary?

We aimed to determine the upper and lower cutoff values to simplify the diagnosis of gestational diabetes mellitus (GDM). We investigated the 50-g oral glucose tolerance test (OGTT) results from 1441 pregnancies and identified 423 gravidas who underwent the 100-g OGTT from 2011 to 2019. We collected the results of 50- and 100-g OGTTs. Moreover, we obtained the sum of the 50-g OGTT and 0-hour values, and the sum of those levels and 1-hour values. We determined the upper cutoff at 50-g OGTT, 0-, 1-hour, sum of 50-g OGTT and 0-hour results, and sum of those levels and 1-hour results for the confirmation of GDM. Also, we determined the lower cutoff at these tests for the exclusion of GDM. The upper cutoffs in 50-g OGTT, 0-, 1-hour, the sum of 50-g OGTT and 0-hour were 222, 115, 212, and 315 mg/dL, respectively. The lower cutoffs in 50-g OGTT, 0-, 1-hour, the sum of 50-g OGTT and 0-hour were 131, 65, 151, and 208 mg/dL, respectively. In addition, we discovered that the upper and lower cutoffs in the sum of 50-g OGTT, 0- and 1-hour values were >516 and <373 mg/dL, respectively. We implemented these cutoffs to our study group at 50-g OGTT and 0-, 1-hour of 100-g OGTT. It could omit 2- and 3-hour sampling in 216 gravidas (51.1%). Our approach was able to simplify GDM diagnostic steps in half of our study group.

Sampling strategies for wastewater surveillance: Evaluating the variability of SARS-COV-2 RNA concentration in composite and grab samples

The shedding of SARS-CoV-2 RNA titers by infected individuals, even asymptomatic and oligosymptomatic ones, allows the use of wastewater monitoring to track the COVID-19 spread in a community. This approach is interesting especially for emerging countries with limited clinical testing capabilities. However, there are still important methodological aspects that need validation so that wastewater monitoring data become more representative and useful for public health. This study evaluated the between-day and within-day variability of SARS-CoV-2 RNA concentrations in 24-hour composite and grab samples from three different sampling points, including two wastewater treatment plants (WTTP) and a sewer manhole. In the between-day evaluation (17 weeks of monitoring), a good agreement between the SARS-CoV-2 RNA concentration of each sampling method was observed. There were no significant differences between the mean concentrations of the grab and composite samples (p-value > 0.05), considering N1 and N2 gene assays. The strong relationship between composite and grab samples was proven by correlation coefficients: Pearson's r of 0.83 and Spearman's rho of 0.78 (p-value < 0.05). In within-day evaluation, 24-hour cycles were analyzed and low variability in hourly viral concentrations was observed for three sampling points. The coefficient of variation (CV) values ranged from 3.0% to 11.5%. Overall, 24-hour profiles showed that viral RNA concentrations had less variability and greater agreement with the mean values between 8 a.m. and 10 a.m, the recommended time for grab sampling. Therefore, this study provides important information on wastewater sampling techniques for COVID-19 surveillance. Wastewater monitoring information will only be useful to public health and decision-makers if we ensure data quality through best practices.

Validation of an automated self-administered 24-hour dietary recall web application against urinary recovery biomarkers in a sample of French-speaking adults of the province of Québec, Canada.

The objective of this study was to validate an automated self-administered 24-hour dietary recall web application (R24W) against recovery biomarkers for sodium, potassium and protein intakes and to identify individual characteristics associated with misreporting in a sample of 61 men and 69 women aged 20-65 years from Québec City, Canada. Each participant completed 3 dietary recalls using the R24W, provided two 24-hour urinary samples and completed questionnaires to document psychosocial factors. Mean reported intakes were 2.2%, 2.1% and 5.0% lower than the urinary reference values, respectively, for sodium, potassium and proteins (significant difference for proteins only (p = 0.04)). Deattenuated correlations between the self-reported intake and biomarkers were significant for sodium (r= 0.48), potassium (r= 0.56) and proteins (r= 0.68). Cross-classification showed that 39.7% (sodium), 42.9% (potassium) and 42.1% (proteins) of participants were ranked into the same quartile with both methods and only 4.8% (sodium), 3.2% (potassium) and 0.8% (proteins) were ranked in opposite quartiles. Lower body esteem related to appearance was associated with sodium underreporting in women (r= 0.33, p = 0.006). No other individual factor was found to be associated with misreporting. These results suggest that the R24W has a good validity for the assessment of sodium, potassium and protein intakes in a sample of French-speaking adults. Novelty: The validity of an automated self-administered 24-hour dietary recall web application named the R24W was tested using urinary biomarkers. According to 7 criteria, the R24W was found to have a good validity to assess self-reported intakes of sodium, potassium and proteins.

Metrics to relate COVID-19 wastewater data to clinical testing dynamics

Wastewater surveillance has emerged as a useful tool in the public health response to the COVID-19 pandemic. While wastewater surveillance has been applied at various scales to monitor population-level COVID-19 dynamics, there is a need for quantitative metrics to interpret wastewater data in the context of public health trends. 24-hour composite wastewater samples were collected from March 2020 through May 2021 from a Massachusetts wastewater treatment plant and SARS-CoV-2 RNA concentrations were measured using RT-qPCR. The relationship between wastewater copy numbers of SARS-CoV-2 gene fragments and COVID-19 clinical cases and deaths varies over time. We demonstrate the utility of three new metrics to monitor changes in COVID-19 epidemiology: (1) the ratio between wastewater copy numbers of SARS-CoV-2 gene fragments and clinical cases (WC ratio), (2) the time lag between wastewater and clinical reporting, and (3) a transfer function between the wastewater and clinical case curves. The WC ratio increases after key events, providing insight into the balance between disease spread and public health response. Time lag and transfer function analysis showed that wastewater data preceded clinically reported cases in the first wave of the pandemic but did not serve as a leading indicator in the second wave, likely due to increased testing capacity, which allows for more timely case detection and reporting. These three metrics could help further integrate wastewater surveillance into the public health response to the COVID-19 pandemic and future pandemics.

Effects of childhood adversity and cortisol levels on suicidal ideation and behaviour: Results from a general population study

Childhood trauma is known to increase the risk of suicidal ideation and behaviours, and has also been linked to hypothalamic pituitary adrenal (HPA) axis dysregulation measured in cortisol levels. Recent evidence has shown that adverse childhood experiences are associated with lower cortisol reactivity to stress and diminished cortisol levels upon awakening in individuals vulnerable to suicide. The present study aimed to investigate whether less traumatic long term difficulties during childhood produced a similar effect on suicidal ideation/behaviour and cortisol levels in a general population sample. Participants (N = 1094; mean age 53 years, 53.7% female) from a large cohort study completed retrospective measures of long-term difficulties during childhood and adolescent years and a measure of history of suicidal thoughts, plans and actions together with a measure of current psychological distress. 24-hour urinary free cortisol samples were collected over two days. The results showed that experiencing childhood long-term difficulties were associated with 21% higher odds of reporting suicidal thoughts or plans in adulthood. Early childhood and adolescent difficulties were equally important predictors of suicide thoughts and plans. However, childhood difficulties were not found to be associated with adult urinary free cortisol, nor were adulthood suicidal thoughts, plans and behaviour associated with adult urinary free cortisol levels. Future research should explore the extent to which childhood difficulties and stressors are related to other indicators of HPA axis functioning. The current findings have implications for clinicians and for the development of future suicide prevention interventions.

Comparison of high-frequency in-pipe SARS-CoV-2 wastewater-based surveillance to concurrent COVID-19 random clinical testing on a public U.S. university campus

Wastewater-based epidemiology (WBE) is utilized globally as a tool for quantifying the amount of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) within communities, yet the efficacy of community-level wastewater monitoring has yet to be directly compared to random Coronavirus Disease of 2019 (COVID-19) clinical testing; the best-supported method of virus surveillance within a single population. This study evaluated the relationship between SARS-CoV-2 RNA in raw wastewater and random COVID-19 clinical testing on a large university campus in the Southwestern United States during the Fall 2020 semester. Daily composites of wastewater (24-hour samples) were collected three times per week at two campus locations from 16 August 2020 to 1 January 2021 (n = 95) and analyzed by reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) targeting the SARS-CoV-2 E gene. Campus populations were estimated using campus resident information and anonymized, unique user Wi-Fi connections. Resultant trends of SARS-CoV-2 RNA levels in wastewater were consistent with local and nationwide pandemic trends showing peaks in infections at the start of the Fall semester in mid-August 2020 and mid-to-late December 2020. A strong positive correlation (r = 0.71 (p < 0.01); n = 15) was identified between random COVID-19 clinical testing and WBE surveillance methods, suggesting that wastewater surveillance has a predictive power similar to that of random clinical testing. Additionally, a comparative cost analysis between wastewater and clinical methods conducted here show that WBE was more cost effective, providing data at 1.7% of the total cost of clinical testing ($6042 versus $338,000, respectively). We conclude that wastewater monitoring of SARS-CoV-2 performed in tandem with random clinical testing can strengthen campus health surveillance, and its economic advantages are maximized when performed routinely as a primary surveillance method, with random clinical testing reserved for an active outbreak situation.

Unpacking determinants and consequences of food insecurity for insulin resistance among people living with HIV: Conceptual framework and protocol for the NOURISH-OK study.

Background:Over the past four decades, advances in HIV treatment have contributed to a longer life expectancy for people living with HIV (PLWH). With these gains, the prevention and management of chronic co-morbidities, such as diabetes, are now central medical care goals for this population. In the United States, food insecurity disproportionately impacts PLWH and may play a role in the development of insulin resistance through direct and indirect pathways. The Nutrition to Optimize, Understand, and Restore Insulin Sensitivity in HIV for Oklahoma (NOURISH-OK) will use a novel, multi-level, integrated framework to explore how food insecurity contributes to insulin resistance among PLWH. Specifically, it will explore how food insecurity may operate as an intermediary risk factor for insulin resistance, including potential linkages between upstream determinants of health and downstream consequences of poor diet, other behavioral risk factors, and chronic inflammation.Methods/design:This paper summarizes the protocol for the first aim of the NOURISH-OK study, which involves purposeful cross-sectional sampling of PLWH (n=500) across four levels of food insecurity to test our conceptual framework. Developed in collaboration with community stakeholders, this initial phase involves the collection of anthropometrics, fasting blood samples, non-blood biomarkers, 24-hour food recall to estimate the Dietary Inflammatory Index (DII®) score, and survey data. A 1-month, prospective observational sub-study (total n=100; n=25 for each food security group) involves weekly 24-hour food recalls and stool samples to identify temporal associations between food insecurity, diet, and gut microbiome composition. Using structural equation modeling, we will explore how upstream risk factors, including early life events, current discrimination, and community food access, may influence food insecurity and its potential downstream impacts, including diet, other lifestyle risk behaviors, and chronic inflammation, with insulin resistance as the ultimate outcome variable. Findings from these analyses of observational data will inform the subsequent study aims, which involve qualitative exploration of significant pathways, followed by development and testing of a low-DII® food as medicine intervention to reverse insulin resistance among PLWH (ClinicalTrials.gov Identifier: NCT05208671).Discussion:The NOURISH-OK study will address important research gaps to inform the development of food as medicine interventions to support healthy aging for PLWH.

Seasonal effects on urinary iodine concentrations in women of reproductive age: An observational study in Tanzania and South Africa

Iodine intake in populations is usually assessed by measuring urinary iodine concentrations (UICs) in spot samples. Hot climate conditions may reduce urine volume, thus leading to overestimations of UIC and thereby masking inadequate iodine intake. We investigated the effects of season on UICs in 2 populations exposed to high-temperature climates. In this observational study, we examined women (18-49 years) in Tanzania (ncold=206; nhot=179) and South Africa (ncold=157; nhot=126) during cold and hot seasons. From each woman in both seasons, we obtained two 24-hour urine collections and 2 spot urine samples, as well as salt, water, and cow's milk samples. We measured the urine volume, UIC, and urinary creatinine concentration (UCC). The 24-hour urinary iodine excretion (UIE) was calculated and used to estimate the iodine intake. We used linear mixed-effects models to test for differences between seasons. In Tanzanian women, we observed no seasonal effect on the urine volume, 24-hour UIE, 24-hour UIC, spot UIC, spot UIC:UCC ratio, or salt iodine concentration. In South African women, the median 24-hour urine volume was 1.40 L (IQR, 0.96-2.05 L) in the winter and 15% lower in the summer (P<0.001). The median 24-hour UIE was 184 µg/day (IQR, 109-267µg/day) in the winter and 34% lower in the summer (P<0.001), indicating a lower iodine intake. As a result, UICs did not significantly differ between seasons in 24-hour collections and spot samples, whereas the spot UIC:UCC ratio differed by 21% (P<0.001) and reflected the lower iodine intake. In both study populations, the within- and between-person variabilities in urine volume, 24-hour UICs, and spot UICs were higher than the variability between seasons. Spot UIC may slightly overestimate the iodine intake in hot temperatures due to concentrated urine, and methods to correct for urine volume may be considered. Local seasonal differences in iodine intakes may also occur in some populations. This trial was registered at http://www.clinicaltrials.gov as NCT03215680.

Chemically modified polystyrene co-loaded with antimicrobial agents

A recent study showed that at least 50% of nosocomial infections are due to medical indwelling devices like surgical guides and prosthetics. This amounts to about 2 million patients affected a year. The reason for such statistics is the growth of microorganisms on the surfaces of the medical devices. There have been many attempts to create antimicrobial materials but most materials are unable to hold more than one antimicrobial agent without a secondary process. The study related to antimicrobial material with more than one type of agent is rarely found in literature. Hence, the objective of this project is to produce an antimicrobial material that can hold more than one antimicrobial agent without the need for a secondary process. The material is produced by sulfonating high impact polystyrene (HIPS) and attaching copper and silver ions. The optimum time of sulfonation of the HIPS was determined by the degree of sulfonation and ion exchange capacity. Then, the sulfonated HIPS were loaded with both copper and silver ions at different ratios. The 6-hour sample yielded the highest degree of sulfonation and ionic exchange capacity of 33.7% and 2.57 meq/g, respectively. In future work, the characterization of the 6-hour sulfonated HIPS sample loaded with copper and silver ions at different concentration ratios will be performed using TGA, DSC and FTIR spectroscopy. Lastly, the efficacy of the antimicrobial properties of the sulfonated HIPS will be tested using different bacterial strains.

Hyponatremia among Postoperative Children Administered with Hypotonic Fluids in a Tertiary Care Hospital: A Descriptive Cross-sectional Study.

Hypotonic solutions in postoperative children may cause hyponatremia. Considering humidity and temperatures in India, this study was conducted to find out the prevalence of hyponatremia among postoperative children who were administered with hypotonic solutions in a tertiary care hospital. A descriptive cross-sectional study was conducted at a tertiary care hospital. Ethical approval was taken from the institutional review board of Christian Medical College, Vellore, India (Reference number: 9177). Children aged less than 15 years undergoing elective surgery, requiring fasting for more than 12 hours post-operatively with normal preoperative electrolytes and renal functions were included. Hypotonic fluids were administered following existent protocol. Electrolytes were repeated immediate postoperatively and at 12-24 hours. Data was entered into and analyzed using the Statistical Package for the Social Sciences version 18.0. Point estimate at 90% Confidence Interval was calculated along with frequency and proportion for binary data. Among 109 participants, hyponatremia in the postoperative period was seen in 53 (48.6%) (40.7-56.5 at 90% Confidence Interval) children. Hyponatremia was found in the immediate postoperative period in 10 (9.2%) children. All received Ringer Lactate as maintenance intra-operatively and none were severe enough to need correction. In the 12-24-hour sample, 43 (39.41%) had hyponatremia and none in severe category. Asymptomatic hyponatremia was noted in normal children planned for elective surgery. Among children managed with the existing institutional perioperative (hypotonic) fluid management protocol, subclinical postoperative hyponatremia within 12-24 hours of surgery was noted in a significant proportion, which was more in the hot and warm months in tropics. There are grounds for switching to isotonic fluids for perioperative management.

Diagnostic accuracy of urine dipstick testing for albumin-to-creatinine ratio and albuminuria: A systematic review and meta-analysis

BackgroundThe accuracy of urine dipsticks to detect increased albuminuria is uncertain. We aimed to assess the diagnostic accuracy of urine dipsticks for detecting albuminuria. MethodsA systematic review of studies that assessed the diagnostic accuracy of urine dipstick testing for detecting albuminuria has been conducted (using as reference standard the albuminuria in a 24-hour sample or the albumin-to-creatinine ratio) in Scopus, PubMed, and Google Scholar. The risk of bias of the included studies has been assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Whenever possible, we performed meta-analyses for sensitivity and specificity. The certainty of the evidence has also been assessed using the Grading of Recommendations Assessment, Development, and Evaluation methodology. ResultsA total of 14 studies have been included in this review, having assessed all albumin-to-creatinine ratio (ACR) as assessed standard. Each study used different dipstick types. The resulting pooled sensitivity and specificity for each cutoff point were as follows: for ACR >30 mg/g (13 studies): 0.82 (95% confidence interval: 0.76–0.87) and 0.88 (0.83–0.91); for ACR 30–300 mg/g (7 studies): 0.72 (0.68–0.77) and 0.82 (0.76–0.89); and for ACR >300 mg/g (7 studies): 0.84 (0.71–0.90) and 0.97 (0.95–0.99), respectively. An overall high risk of bias, an important heterogeneity in all pooled analysis, and a very low certainty of the evidence have been found. ConclusionsPooled sensitivity and specificity of urine dipsticks have been calculated for different ACR cutoff points. However, the dipstick types differed across studies, and the certainty of the evidence was very low. Thus, further well-designed studies are needed to reach more confident estimates and to assess accuracy differences across dipstick types. RegistrationPROSPERO (CRD42019124637).

Improving the quality of wastewater treatment plant monitoring by adopting proper sampling strategies and data processing criteria

Monitoring is a crucial operation for plant management. However, proper sampling procedures and data processing criteria are not always adopted. Wastewater treatment plants work under dynamic conditions, which poses a challenge for a correct performance assessment. The aim of this work is to analyse some important aspects of wastewater sampling and data processing, to identify case by case methods which should to be adopted in order to obtain reliable and consistent information on plant performance. The study was conducted through simulations and real data analyses. It turned out that: a) the preferable 24-hour composite sampling procedure is the flow-proportional mode; in addition, the required sampling frequency (i.e. the number of sub-samples to be taken to make the 24-h composite sample) increases as the percentage of population discontinuously discharging the monitored substance decreases; b) a Variability Index was defined to help find the minimum sampling frequency (i.e. the number of 24-h composite samples per year) for the calculation of annual mass flows with an acceptable uncertainty; and c) criteria were proposed for the identification of pseudo-steady state periods needed to calculate reliable mass balances and plant performance indicators.

Efficacy of ethylene oxide-sterilized waterproof cases for handheld cameras as sterile barriers for intraoperative imaging and recording.

To evaluate the efficacy of ethylene oxide (EtOH) sterilization of 4 different waterproof camera cases and the ability of those sterilized cases to maintain a sterile barrier for intraoperative camera use. 3 action cameras, 1 smartphone, and associated waterproof cases. Cases were inoculated by immersion in medium containing Staphylococcus pseudintermedius, Escherichia coli, and Pseudomonas aeruginosa and then manually cleaned and subjected to EtOH sterilization. Cameras were disinfected, loaded into sterile cases, and sterilely operated for 2 hours. Samples were collected from cases after inoculation, EtOH sterilization, camera loading, and 1 and 2 hours of operation and from all cameras after 2 hours of operation. Procedures were repeated twice, followed by an additional challenge round wherein cameras were purposefully contaminated prior to loading. All samples underwent bacterial culture. All cases were successfully sterilized, and loading of nonsterile cameras into sterile cases caused no contamination when cameras had been disinfected beforehand. Nonpathogenic environmental contaminants were recovered from 6 of 64 culture samples and 2 of 4 room samples. During the challenge round, only the postload sample for 1 case yielded E coli, suggesting sterile glove contamination; however, postload, 1-hour, and 2-hour samples for the GoPro case yielded E coli and S pseudintermedius, suggesting major contamination. Results suggested that the evaluated cases can be safely sterilized with EtOH and used for image acquisition by aseptically prepared surgeons when cameras are disinfected prior to loading. Except for the GoPro camera, camera use did not jeopardize sterile integrity.

XPS and FTIR investigations of the transient photocatalytic decomposition of surface carbon contaminants from anatase TiO2 in UHV starved water/oxygen environments

This paper explores the transient photocatalytic oxidation mechanism of carbon contaminants from a high surface area anatase TiO2 pellet under starved water/oxygen reaction conditions created when specimens are irradiated via a 375 nm UV laser inside the UHV analysis chamber of an XPS spectrometer. Complementary results are also provided following similar UV irradiations and reaction procedures in an evacuated in situ reaction cell of a Fourier-transform infrared spectrometer (FTIR). An interactive and non-steady state transient photocatalytic reaction is observed between surface carbon species and strongly adsorbed H2O brought to the exterior surface of the pellet via UV photodesorption from within the deeper lying pores of the pellet. The reaction stoichiometry and quantum efficiency of the reaction are reported at various irradiation intensities. In situ FTIR spectral features are also presented and discussed for a non-UV treated TiO2 sample and a 2-hour UV-treated TiO2 sample under evacuated conditions also showing the decomposition of carbon contaminants species and the consumption of adsorbed water/hydroxyls with the ensuing formation of carboxyl (HO-CO) carbon species and isolated surface hydroxyls. The photocatalytic decomposition of carbon species and the concomitant consumption of oxygen containing species was also tracked by following the XPS spectral changes of a UV-irradiated area on the pellet surface compared to a dark reference spot on the same specimen. Eight different reaction cases at four different UV intensities, repeated twice each, were also investigated using separate pieces of the same TiO2 media. The measured stoichiometry for the decomposition of carbon species and consumption of oxygen ranged from 0.53 during the first 10–20 min of irradiation and increased to 0.65 with an average value of 0.59 and a standard deviation of 0.11. These data suggest that the reaction product and leaving group from the TiO2 surface is primarily CO2 during the first 10–20 min of initial reaction with perhaps a small fraction of CO toward the end of reaction. Heating the sample specimen to 100 °C for 2-hour inside the XPS-UHV analysis chamber prior to UV illumination was effective in eliminating photocatalytic oxidation and carbon removal from the surface thereby demonstrating that strongly adsorbed water (prior to heating in vacuum) was a critical and limiting reagent in the overall H2O transport and reaction process.Photon efficiencies for the reaction were calculated based on the number of carbon species removed from the XPS-observable surface versus the number of the UV photons adsorbed in the topmost 2 nm of the sample. The highest photon efficiency observed was 0.0186 after 5–10 min of UV exposure at 1.5 mW/cm2. All reaction cases showed a significant efficiency drop after 30 min of UV irradiation due to the consumption of the adsorbed reactants, both carbon and water. From detailed deconvolution of the XPS C 1s spectra, UV irradiation showed a high selectivity towards hydrocarbon contaminant decomposition, which was 75% ± 5% of all carbon species removed.