Laboratory Grade Research Articles

Interactions between antibiotic removal, water matrix characteristics and layered double hydroxide sorbent material

Sorption by layered double hydroxides (LDH) is gaining substantial interest for remediating emerging contaminants, including pharmaceuticals from wastewaters. Findings from a sorbent material performing successfully in lab-based studies using non-environmental (laboratory-sourced) water cannot be assumed to translate to equal performance under environmental downstream applications. However, studies evaluating sorbent material performance for removal of pollutants and understanding material interactions with environmental waters are limited. This study evaluates the removal of the antibiotic amoxicillin (AMX) using a Mg2Al–NO3-LDH sorbent material from laboratory-grade water and wastewater effluent (WWE). AMX is successfully removed (94.53 ± 4.30 % within 24 h) in laboratory-grade water (under batch sorption conditions: 100 μg/L AMX, 0.2 g/L LDH, 20 °C). The comparison of LDH removal performance in laboratory grade and WWE shows a decreased maximum removal of AMX in WWE (13.39 ± 5.53 %). A lower final AMX concentration is observed in the WWE without the presence of LDH, compared to the ‘removal’ experiments in WWE with the presence of LDH, indicating a contribution of non-sorption removal pathways of AMX. This is proposed to be due to the difference in metal concentrations in the WWE with and without LDH present. The presence of LDH is found to decrease concentrations of metal pollutants in WWE, such as Zn concentration decreasing by 85 % over 24 h, changing water characteristics. Overall, this paper reports that an LDH performs differently in laboratory-sourced water and a wastewater effluent. This provides evidence that sorbent material performance needs to be evaluated in complex water matrices to ensure that it is representative of how a sorbent material will perform in an environmental application, which is the end goal of developing such technologies. Finally, good practice recommendations are provided for future lab-scale sorption experiments evaluating the performance of any new sorbent materials for water treatment applications.

Acute toxicity of sodium chloride-based road salt formulations to juvenile aquatic invertebrates

Globally millions of tons of de-icing agents are applied each year, and about half of these salts enter surface water adjacent to sites of application. While numerous studies have demonstrated the potential impact de-icing agents such as NaCl have on freshwater invertebrates, many of these studies have used laboratory grade NaCl for evaluation, and less is known about the relative toxicity of formulations. The purpose of this study was to compare the 24 and 96 h LC50s of NaCl and two NaCl-based road salt formulations for three aquatic species: juvenile Hyalella azteca, Hexagenia rigida, and Chironomous dilutus. As expected, LC50 values were greater for 24 h exposures than 96 h exposures. However, the relative toxicity of the road salt formulations varied by exposure duration and species. Although the acute LC50 values found in this study were within environmental concentrations of chloride ions reported by existing literature, more research is needed to evaluate chronic or sublethal effects of road salt formulations on a range of freshwater macroinvertebrates.

Calibrations, Validations, and Checks of a Dual 23 nm and 10 nm Diffusion Charger-Based Portable Emissions Measurement System (PEMS).

The upcoming Euro 7 vehicle exhaust emissions regulation includes particle number (PN) limits for all vehicles, not only those with direct fuel injection. It also sets the lower detection particle size of the PN methodology to 10 nm from 23 nm. Recently, a commercial diffusion charger-based PEMS added the possibility of switching the lower size between 23 nm and 10 nm. In this study, we assessed the dual PEMS in the calibration laboratory using diffusion flame soot or spark discharge graphite particles following the regulated procedures. Furthermore, we compared the dual PEMS with a laboratory grade system (LABS) using soot, graphite, and vehicle exhaust particles. To put the results into perspective, we added comparisons (validations) of two additional 23 nm PEMSs with LABSs over a three-year period. The results showed that the differences of the 23 nm PEMSs remained the same (around 35% underestimation) over the years and were similar to the dual PEMS. This difference is still well within the permissible tolerance from the regulation (50%). We argued that the reason is the calibration material used by the manufacturer (spark discharge graphite). We demonstrated that calibrating with combustion soot could reduce the differences. The 10 nm PEMS gave similar results but with much smaller differences, indicating that the calibration material is of less importance for the Euro 7 step. The results showed that the measurement uncertainty has not increased but rather decreased for the specific PEMS switching from 23 nm to 10 nm.

Validity of the Hawkin Dynamics Wireless Dual Force Platform System Against a Piezoelectric Laboratory Grade System for Vertical Countermovement Jump Variables.

Dos'Santos, T, Evans, DT, and Read, DB. Validity of the Hawkin dynamics wireless dual force platform system against a piezoelectric laboratory grade system for vertical countermovement jump variables. J Strength Cond Res 38(6): 1144-1148, 2024-The aim of this study was to determine the criterion validity of the Hawkin Dynamics (HD) wireless dual force platform system for assessing vertical countermovement jump (CMJ) variables, compared with those derived from a Kistler piezoelectric laboratory grade force platform system. During a single testing session, HD force platforms were placed directly on top of 2 adjacent Kistler force platforms to simultaneously collect vertical ground reaction forces produced by 2 male recreational soccer players (age: 29.0 ± 2.8 years, height: 1.79 ± 0.01 m, mass: 85.6 ± 4.7 kg) that performed 25 vertical CMJs each. Sixteen vertical CMJ variables pertaining to jump height (JH), flight time (FT), time-to-take off (TTT), countermovement depth, body weight (BW), propulsive and braking mean, and peak powers, forces, and impulses were compared between systems. Fixed bias was observed for 6 of 16 variables (peak and mean braking power, mean propulsion force, TTT, FT, and BW), while proportional bias was present for 10 of 16 variables (peak and mean propulsive and braking force, TTT, FT, peak and mean braking power, mean propulsive power, and BW). For all variables regardless of fixed or proportional bias, percentage differences were ≤3.4% between force platform systems, with near perfect to perfect correlations (r or ρ = 0.977-1.000) observed for 15 of 16 variables. The HD dual wireless force platform system can be considered a valid alternative to a piezoelectric laboratory grade force platform system for the collection of vertical CMJ variables, particularly outcome (i.e., JH, reactive strength index modified) and strategy variables (countermovement depth).

Local experience of laboratory activities in a BS physical therapy course: integrating sEMG and kinematics technology with active learning across six cohorts.

Integrating technology and active learning methods into Laboratory activities would be a transformative educational experience to familiarize physical therapy (PT) students with STEM backgrounds and STEM-based new technologies. However, PT students struggle with technology and feel comfortable memorizing under expositive lectures. Thus, we described the difficulties, uncertainties, and advances observed by faculties on students and the perceptions about learning, satisfaction, and grades of students after implementing laboratory activities in a PT undergraduate course, which integrated surface-electromyography (sEMG) and kinematic technology combined with active learning methods. Six cohorts of PT students (n = 482) of a second-year PT course were included. The course had expositive lectures and seven laboratory activities. Students interpreted the evidence and addressed different motor control problems related to daily life movements. The difficulties, uncertainties, and advances observed by faculties on students, as well as the students' perceptions about learning, satisfaction with the course activities, and grades of students, were described. The number of students indicating that the methodology was "always" or "almost always," promoting creative, analytical, or critical thinking was 70.5% [61.0-88.0%]. Satisfaction with the whole course was 97.0% [93.0-98.0%]. Laboratory grades were linearly associated to course grades with a regression coefficient of 0.53 and 0.43 R-squared (p < 0.001). Integrating sEMG and kinematics technology with active learning into laboratory activities enhances students' engagement and understanding of human movement. This approach holds promises to improve teaching-learning processes, which were observed consistently across the cohorts of students.

Nutrient status and production of fodder beet irrigated with saline-sodic water in Mediterranean calcareous soils

ABSTRACT The impact of drip irrigation with saline-sodic water on the nutrient status and productivity of fodder beet (Beta vulgaris) was evaluated in rainy and dry Mediterranean cropping seasons. Two field experiments were conducted during two growing seasons (winter and summer) in calcareous soil (31% CaCO3) of Sais area, Northwestern Morocco. The rainfall was 337 mm for winter and 53 mm for summer. Four salinity levels of irrigation water (ECi) were investigated: control (1ds m−1), 4, 6, and 10 ds m−1. The ECi levels were prepared by adding sodium chloride (NaCl, laboratory grade, 99.5%) to water. The results showed that the soil salinity (ECs) was related to the growing season and the irrigation water salinity (ECi). The depressive effect of salinity on the whole plant dry biomass (−25% as average) was observed only in the summer crop cycle at different ECi ≥ 4 ds m−1 compared to control. The plant NaCl uptake for both seasons could be predicted by a linear model: Y (kg ha−1 of NaCl) = 36.3 ECi + 23.6 Q − 101.3 (adjusted R2 = 0.88) where Q = total dry biomass (t ha−1). Saline-sodic irrigation water reduced the contents of boron, calcium, and magnesium in the plants. The exchangeable sodium percentage (ESP) in the soil exceeded 41% at ECi ≥ 4 ds m−1 for both seasons. The study demonstrated that fodder beet escapes the negative impact of salt stress in the rainy season. However, the high ESP recorded at harvest did not reveal the efficacy of fodder beet in NaCl removal from the soil.

Research progress on optimization of in vitro isolation, cultivation and preservation methods of dental pulp stem cells for clinical application.

Due to high proliferative capacity, multipotent differentiation, immunomodulatory abilities, and lack of ethical concerns, dental pulp stem cells (DPSCs) are promising candidates for clinical application. Currently, clinical research on DPSCs is in its early stages. The reason for the failure to obtain clinically effective results may be problems with the production process of DPSCs. Due to the different preparation methods and reagent formulations of DPSCs, cell characteristics may be affected and lead to inconsistent experimental results. Preparation of clinical-grade DPSCs is far from ready. To achieve clinical application, it is essential to transit the manufacturing of stem cells from laboratory grade to clinical grade. This review compares and analyzes experimental data on optimizing the preparation methods of DPSCs from extraction to resuscitation, including research articles, invention patents and clinical trials. The advantages and disadvantages of various methods and potential clinical applications are discussed, and factors that could improve the quality of DPSCs for clinical application are proposed. The aim is to summarize the current manufacture of DPSCs in the establishment of a standardized, reliable, safe, and economic method for future preparation of clinical-grade cell products.

Dietary contribution of iron from limestone and dicalcium phosphate for broiler chickens

Iron is routinely supplemented in broiler feeds aiming to prevent dietary deficiencies. Limestone and phosphates are very rich in Fe; however, its contribution from these sources have not been thoroughly investigated with chickens. The present research was conducted to evaluate live performance and blood parameters of broilers when using limestone and dicalcium phosphate as sources of Fe. A total of 576 one-day-old male Cobb x Cobb 500 were allocated into a total of 72 battery cages, 6 treatments with 12 replication cages of 8 chicks at placement. Chicks were fed diets formulated with corn, soybean meal (SBM) with laboratory grade calcium carbonate and phosphoric acid (having traces of Fe). All chicks were fed a common prestarter without Fe supplementation (analyzed total 58.2 ± 2.4 mg/kg Fe) from placement to 7 d. Allocation of birds to dietary treatments was completely randomized on day 8. Treatments had increasing Fe derived from commercial limestone and dicalcium phosphate (analyzed Fe 7,218 and 4,783 mg/kg, respectively) progressively replacing calcium carbonate and phosphoric acid to provide graded increases in total Fe (analyzed Fe in the feeds were 57.6 ± 2.1, 92.0 ± 2.3, 124.1 ± 2.7, 159.3 ± 3.1, 187.2 ± 3.2, 223.7 ± 3.6 mg/kg, respectively). There were no effects of dietary Fe on live performance, hematocrit, and hemoglobin the end of the study on day 28 (P > 0.05). Increasing dietary Fe from commercial limestone and dicalcium phosphate led to a linear reduction in the percent ileal digestible Fe. However, linear increments in Fe retention, serum ferritin and liver Fe occurred when compared to feeds without Fe derived from limestone and phosphate dicalcium. It is concluded that Fe from limestone and dicalcium phosphate can be partially utilized by broiler chickens. It was estimated that the Fe retained from limestone and dicalcium phosphate is of 1.9%. Broilers fed corn-soy feeds (58.2 mg/kg Fe) do not require supplemental Fe.

Dental Environment Stress Among Iraqi Students: A Qualitative Study

Objective: To determine the degree of psychological stress in undergraduate dental students &amp; explore related gender variation. Methods: 100 5th-year dental students at Al-Rafidain University College (RUC), Iraq, participated in the study by completing The Modified Dental Environment Stress Questionnaire (DES). Results: The primary sources of stress were found to be Completing the clinical requirement, the Atmosphere created by the clinical supervisors, Full working day, Patients being late or not showing up for their appointments, Difficulty in learning precision manual skills required for clinical and laboratory work, examination, and grades &amp; fear of unemployment. The highest score source was (patients being late or not showing), followed by (examination and grades). Regarding gender differences, the (Full working day) was the highest stressor item for the male student’s team, while female students chose (Atmosphere created by clinical supervisors) as their top stressor. Conclusion: The highest perceived sources of stress reported by students should be further explored by longitudinal studies, and strategies to minimize the resulting stress should be developed and implemented since psychological stress in study years of dentistry predicts occupational stress later.

Young’s modulus of illitic clay and CaCO3 mixtures during thermal treatment up to 1100 °C

The dynamic Young’s modulus of samples, made from a mixture of illitic clay and laboratory grade CaCO3 with 6% addition of 3% solution of polyvinyl alcohol in anorthite stoichiometry is studied. The samples with different CaCO3 contents, namely 17.6%, 21.6%, and 25.6% are made by dry pressing. The measurements of the dimensions, mass, and resonance frequency of the samples are performed for the determination of the dynamic Young’s modulus in the temperature interval from 25 °C to 1100 °C. The influence of the amount of CaCO3 on the Young’s modulus of the samples is investigated. During the firing of the studied samples, the values of Young’s modulus increase due to the liberation of physically bound water (up to 250 °C) and sintering (above 850 °C). The values of Young’s modulus after a firing reach 16.7 – 18.4 GPa, which is about 6 – 9 times higher as the values for the raw samples.

Photosynthetic conversion of carbon dioxide from cement production to microalgae biomass

Production of microalgae is a potential technology for capturing and recycling carbon dioxide from cement kiln emissions. In this study, a process of selecting a suitable strain that would effectively utilize carbon dioxide and generate biomass was investigated. A down-selection screening method was applied to 28 strains isolated from the area surrounding a commercial cement plant. In laboratory-scale (1 L) continuous-mode chemostats, observed productivity was > 0.9 g L−1 d−1 for most strains studied. Chlorella sorokiniana (strain SMC-14M) appeared to be the most tolerant to cement kiln gas emissions in situ, delivered under control of a pH-stat system, and was down-selected to further investigate growth and biomass production at large-scale (1000 L) cultivation. Results demonstrated little variability in lipid, crude protein, and carbohydrate composition throughout growth between kiln-gas grown algal biomass and biomass produced with laboratory grade CO2. The growth rate at which the maximum quantity of CO2 from the emissions is recycled also produced the maximum amount of the targeted biomass components to increase commercial value of the biomass. An accumulation of some heavy metals throughout its growth demonstrates the necessity to monitor the biomass cultivated with industrial flue gases and to carefully consider the potential applications for this biomass; despite its other attractive nutritional properties.Key points• Studied high biomass producing algal strains grown on CO2from cement flue gas.• Chlorella sorokiniana SMC-14M grew well at large scale, in situ on cement flue gas.• Demonstrated the resulting commercial potential of the cultured algal biomass.

Leveraging large soil spectral libraries for sensor-agnostic field condition predictions of several agronomically important soil properties

Global pressures to improve soil organic carbon sequestration and soil health in general amongst the world’s agricultural soils are creating a demand for improved practice to drive positive and sustainable changes in the natural capital of soils. Incentive programs aimed to promote this must be informed by accurate observations of the state of soils, both temporally and spatially. Soil spectral inference is a useful method for capturing the state of soils cost-effectively, but the price of standard laboratory grade visible and near-infrared (Vis-NIR) sensors can limit its application. Further, the acquisition of spectra by these laboratory grade sensors is performed primarily in air-dried and ground condition, adding a time lag to information retrieval. Recently, low-cost, portable miniaturised near-infrafred (NIR) spectrometers have become available and have shown to be a viable alternative for the measurement of several agronomically important soil properties, which are also vital to the maintenance of soil health, including soil organic carbon (SOC), and cation exchange capacity (CEC). However, the implementation of new spectrometers, to new locations requires the creation of new spectral libraries, an expensive and labour-intensive process requiring large amounts of soil analytical and spectral data gathering. Thus, existing, laboratory grade Vis-NIR spectral libraries present a high-quality and high-resolution resource to leverage. This work demonstrates how existing spectral library resources can be accessed with cheaper, portable miniaturised NIR spectrometers with appropriate spectral filtering, and appropriate transformation matrices. In addition, the work shows that by correcting for the influences of spectral differences between soils scanned in field condition, and those prepared for analysis in the laboratory, greater uptake of spectral inference as a tool to evaluate the state of soils can be enabled. This work also demonstrates how large existing laboratory grade spectral libraries such as the CSIRO national Australian Vis-NIR soil spectral library can be queried and using memory-based learning or similar methods, such as RS-Local, and the most appropriate samples may be identified to be used for the prediction of soil properties. This work builds off an existing framework for the use of soil spectral inference for monitoring the state of soil, the Australian 2021 Soil Organic Carbon Credits Methodology Determination. Methods are demonstrated for the prediction of nine agronomically important soil properties, SOC, pH in water, pH in CaCl2, electrical conductivity, CEC, and exchangeable Ca, K, Mg and Na. For SOC a model using only 20 local samples was produced in this work with a Lin’s concordance correlation coefficient (LCCC) of 0.72, surpassing both the minimum requirement under the carbon credits methodology determination (LCCC 0.6), and a 50 sample local only model (LCCC 0.61). This example demonstrates that a significant further potential cost saving in laboratory analysis across soil monitoring projects can be achieved through selectively leveraging a large spectral library resource.

An Experimental Correlation of Degradation with Cell Reversible and Irreversible Expansion Measurement in Pouch Cells

Lithium-ion batteries are used widely in portable devices and play an increasingly significant role in transportation and grid storage. These batteries degrade when they undergo charging and discharging and also when they are stored (calendar aging). The rate of this degradation depends on how the batteries are used and under what conditions. As the battery is cycled, its internal impedance and individual electrode capacities change, causing a change in its electrical performance. In addition, changes in the reversible and irreversible expansion of the cell are also observed. Of particular concern for pack design is the continued growth of irreversible battery thickness, thus affecting the stresses in the battery pack which is typically constrained to occupy a fixed volume. Understanding these dimensional changes will play an important role in accommodating this expansion over life for pack design.Due to the aforementioned dimensional changes, the stresses that the battery faces at the beginning of life are different from the stress at the end of life when battery expansion is constrained due to packaging. To understand the impact of external stress/pressure on battery aging, we have designed a specialized spring loaded fixture which allows for operating the battery under relatively constant pressure, over the entire cell life, while simultaneously measuring the cell expansion. Battery thickness changes were measured for 82 identical pouch cells fabricated at the UofM Battery Laboratory using Targray NMC 622 Single Crystal cathode powder and Superior SLC 1520-T anode powder. The cells were loaded into the fixtures with 4 different initial pressures of 5 psi (standard beginning of life pressure), 15 psi, 25 psi (expected end of life pressure) and without any applied pressure. A baseline cycling protocol was established which included a modest amount of fast charging and cells were divided into three different thermal chambers to simulate the impacts of environmental temperature (room 25C, cold 0C, and hot 45C). Finally the impact of depth of discharge was also included in the test matrix. Three cells were assigned to each test condition to account for cell to cell variability. Instrumenting all the cells with laboratory grade LVDT expansion sensors would be prohibitively expensive [1]. To overcome the issue we used low-cost Inductive Displacement Sensors which provide inexpensive and high-resolution measurements of battery expansion under various load conditions. Further details on the sensor design and implementation are given in [2].

Enhancing Effect of Boron-Doping on the Activity of Nife-MOF-74 Towards Oxygen Evolution Reaction in Alkaline

Water splitting has drawn significant attention due to the capability of mass-producing hydrogen, which is considered a promising alternative to fossil fuels in the future.[1] The development of electrochemical energy conversion and storage technologies, such as water electrolyzers, metal-air batteries, and regenerative fuel cells, is of great importance to support the transition to clean and renewable energy.[2] Based on the merits of high surface area, 3D periodic porous structure, large porosities, diverse composition and well-defined metal centers, metal–organic frameworks (MOFs) and their derivatives have been widely exploited as OER electrocatalysts.[3]However, MOFs have some limitation to be used as a OER catalysts, considering their poor stabilities (in water, especially basic/acidic conditions) and low electrical conductivities. Incorporation of boron atoms into an aromatic carbon framework offers a wide variety of functionalities. [4] In this work, the flower-like bimetallic NiFe-MOF-74 dopped with boron were fabricated, and they exhibit superior catalytic activity with a very low overpotential of 318 mV for OER at a laboratory grade current density of 10 to 100 mA/cm2 and fast reaction kinetics with a small Tafel slope of 89 mV dec-1 in 1.0 M KOH using a catalyst fabrication process that is scalable to commercial levels. Additional work is required to demonstrate current densities at commercial levels. Reference [1] L. Fan, Z. Kang, M. Li, D. Sun, Recent progress in pristine MOF-based catalysts for electrochemical hydrogen evolution, oxygen evolution and oxygen reduction, Dalton Trans. 50 (2021) 5732–5753. https://doi.org/10.1039/D1DT00302J.[2] Bimetallic metal–organic frameworks and MOF-derived composites: Recent progress on electro- and photoelectrocatalytic applications - ScienceDirect, (n.d.). https://www.sciencedirect.com/science/article/pii/S0010854521005385 (accessed April 27, 2022).[3] J. Du, F. Li, L. Sun, Metal–organic frameworks and their derivatives as electrocatalysts for the oxygen evolution reaction, Chem. Soc. Rev. 50 (2021) 2663–2695. https://doi.org/10.1039/D0CS01191F.[4] Y. Xie, Z. Meng, T. Cai, W.-Q. Han, Effect of Boron-Doping on the Graphene Aerogel Used as Cathode for the Lithium–Sulfur Battery, ACS Appl. Mater. Interfaces. 7 (2015) 25202–25210. https://doi.org/10.1021/acsami.5b08129.

Evaluation of Generic Fertiliser as an Alternative Inorganic Nitrogen Source for Ethanolic Glucose Fermentation by Saccharomyces cerevisiae

In the studies and production of bioethanol, the preferred fermenting yeast (Saccharomyces cerevisiae) is usually cultured in liquid broth that contains yeast extract and peptone. However, the use of these laboratory and scientific grade chemicals is costly, making them impractical for mass bioethanol production. Therefore, this study was conducted to evaluate the feasibility of glucose ethanolic fermentation by S. cerevisiae using generic fertiliser formulations to provide inorganic nitrogen, phosphorus, potassium and trace elements (NPK-TE). Fermentation media of different generic fertiliser strength at 0.5X, 1.0X and 2.0X Fertiliser Nitrogen Equivalents (FNE), as compared to the conventional Yeast Extract-Peptone (YEP) medium as control, was used as fermentation broth during the ethanolic fermentation of glucose. Based on the results, S. cerevisiae cultured in YEP broth produced the highest cell concentration for both wet (21.93 g/L) and dry cells (3.87 g/L), with rapid increment observed in the first 72 h of fermentation. By the end of the fermentation period, lactic acid (3.14 g/L) and acetic acid (0.96 g/L) levels were recorded to be the lowest in YEP medium while their concentration (lactic acid, 8.08 g/L) and (acetic acid, 2.67 g/L) were highest in 2.0X FNE fertiliser medium. Results indicated that the best theoretical ethanol yield (TEY) among the fertiliser media was achieved when fermentation was performed in the 0.5X FNE fertiliser medium, with a TEY of 86.18%. TEY yields were 78.68% and 51.54% in broth with 1.0X and 2.0X FNE, respectively. In general, all three fertiliser media supported ethanolic fermentation of glucose, with the 0.5X FNE fertiliser broth showing a yield that is significantly close to the conventional YEP medium, as seen in the statistical analysis. Similarities in other fermentation profiles such as acetic acid, lactic acid, and biomass production, as well as glucose utilisation, between the results from the YEP samples and samples from the fertiliser broths (at 0.5X and 1.0X FNE) have also shown that generic fertiliser has the potential to be used as an alternative medium to replace the conventional YEP to produce ethanol at a lower cost.

Formulation of Steinernema yirgalemense in gel for long-term storage at room temperature

The use of entomopathogenic nematodes (EPNs) offers the potential of reducing the use of chemical insecticides in the agricultural industry. Hydrogels for the long-term storage of EPNs may have the potential to improve the storage ability of EPNs. In this study, infective juveniles (IJ) of a South African isolate Steinernema yirgalemense were formulated in different gels, which included a laboratory grade and consumer grade of agar, as well as STOCKOSORB® 660, and compared it with IJ in water. Their survival and pathogenicity of the IJ were investigated at 25 °C. The last instar larvae of Tenebrio molitor were used to test the pathogenicity of the IJs 6 weeks postformulation. IJs stored in 1% and 1.5% agar formulations were found to provide the best survival of 77% and 82% after 6 weeks in formulation. Results indicate consumer grade agar to be comparable with laboratory grade and can be used as a cheaper alternative for the formulation of S. yirgalemense. When comparing the STOCKOSORB® 660 formulations, 80% IJ survival was recorded in a formulation of 1 g in 50 ml of water, with 50% of the IJs surviving in a formulation of 1 g in 100 ml of water. The IJs formulated and stored in STOCKOSORB® 660 gel were found to be more virulent to Tenebrio molitor than were the IJs formulated in agar.

A novel home-use culture mechanism for identifying microbial load in urine samples.

Diagnosing a urinary tract infection (UTI) is typically a clinical procedure involving multiple steps. The need to perform a test depends on the presence of relevant symptoms. Given the current pandemic situation, visiting a clinic may not be a preferable choice for many users. Many vulnerable groups of patients, namely, males with certain predispositions and pregnant women, may not present with symptoms of UTI and may go undiagnosed, which could give rise to a more complicated situation. So far, microbial cultures have been used as the gold standard for the diagnosis of an infection. However, performing microbial cultures currently requires trained professionals and laboratory grade equipment. Therefore, there is a need for a home-use culture kit that can serve this purpose. To our knowledge, no such kit exists. Here, we present a feasibility study of an affordable and easy-to-use home-based setup for quantifying bacterial load in a urine. We believe that such a system can be used by people at home to monitor recurrent UTI infections and also by physicians to remotely monitor and prescribe narrow-spectrum antibiotics for more effective treatment.

LearningRlab: Educational R Package for Statistics in Computer Science Engineering

This paper describes and evaluates the educational interest of LearningRlab, an educational R package developed for teaching statistics in computer science engineering. The package was developed by final degree project students to be used as an educational environment for statistics students who evaluated the package and provided feedback for future versions. Such a process increases the motivation of both groups of students. This paper presents how the use of the R packages conceived and developed for engineering education can improve the learning process in the computer science engineering bachelor’s degree. Two different evaluations, one performed by a group of statistics students, and the other performed by final degree project students, were used to evaluate the impact on the learning process of the first version of the package to develop the second version of the package, which corrects and enhances the first version. The evaluation results show a positive effect on the learning process in both subjects. The analysis of the learning outcomes reflected in the grades of the experimental and control groups demonstrates that LearningRlab can be used as a teaching aid for statistics and final degree project subjects of the computer science engineering degree. The average laboratory grade of the students who used the package (5.76) was noticeably higher than the average laboratory grade of students who did not use it (1.84).

Accelerated Ultraviolet Treatment of Carbamazepine and NDMA in Water under 222 nm Irradiation.

Krypton chloride (KrCl*) excimer ultraviolet (UV) light may provide advantages for contaminant degradation compared to conventional low-pressure (LP) UV. Direct and indirect photolysis as well as UV/hydrogen peroxide-driven advanced oxidation (AOP) of two chemical contaminants were investigated in laboratory grade water (LGW) and treated secondary effluent (SE) for LPUV and filtered KrCl* excimer lamps emitting at 254 and 222 nm, respectively. Carbamazepine (CBZ) and N-nitrosodimethylamine (NDMA) were chosen because of their unique molar absorption coefficient profiles, quantum yields (QYs) at 254 nm, and reaction rate constants with hydroxyl radical. Quantum yields and molar absorption coefficients at 222 nm for both CBZ and NDMA were determined, with measured molar absorption coefficients of 26 422 and 8170 M-1 cm-1, respectively, and QYs of 1.95 × 10-2 and 6.68 × 10-1 mol Einstein-1, respectively. The 222 nm irradiation of CBZ in SE improved degradation compared to that in LGW, likely through promotion of in situ radical formation. AOP conditions improved degradation of CBZ in LGW for both UV LP and KrCl* sources but did not improve NDMA decay. In SE, photolysis of CBZ resulted in decay similar to that of AOP, likely due to the in situ generation of radicals. Overall, the KrCl* 222 nm source significantly improves contaminant degradation compared to that of 254 nm LPUV.

Biochemical conversion of waste paper slurries into bioethanol

Waste papers, which are a major constituent of municipal wastes, can be repurposed into the production of bioethanol, a renewable and ecofriendly fuel. Many studies have produced ethanol from print-grade papers, but literature on conversion of waste cartons is sparce. In this study, waste corrugated cartons and print-grade papers were reduced into slurries and were subjected to physical and chemical tests to determine their suitability for biosynthesis. Cellulose fibers in the slurries were directly hydrolyzed into glucose without prior pretreatment by dilute hydrochloric acid, and fermented into ethanol using Saccaromyces cerevisae. Density, flammability, color, odor, non-volatile residue and other qualitative tests were conducted on the ethanol produced. Glucose yield and the extraction efficiency in cellulose hydrolysis were significantly higher for waste cartons than print paper slurries. Qualitative tests reveal that the ethanol produced from both slurries has physical and chemical characteristics that are comparable to laboratory grade ethanol, contains no toxic impurities, and is suitable for use as a biofuel.