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In this study, we perform an extensive evaluation of a simple model for hydrate equilibrium calculations of binary, ternary, and limited quaternary gas hydrate systems that are of practical interest for separation of gas mixtures. We adopt the model developed by Lipenkov and Istomin and analyze its performance at temperature conditions higher than the lower quadruple point. The model of interest calculates the dissociation pressure of mixed gas hydrate systems using a simple combination rule that involves the hydrate dissociation pressures of the pure gases and the gas mixture composition, which is at equilibrium with the aqueous and hydrate phases. Such an approach has been used extensively and successfully in polar science, as well as research related to space science where the temperatures are very low. However, the particular method has not been examined for cases of higher temperatures (i.e., above the melting point of the pure water). Such temperatures are of interest to practical industrial applications. Gases of interest for this study include eleven chemical components that are related to industrial gas-mixture separations. Calculations using the examined methodology, along with the commercial simulator CSMGem, are compared against experimental measurements, and the range of applicability of the method is delineated. Reasonable agreement (particularly at lower hydrate equilibrium pressures) between experiments and calculations is obtained considering the simplicity of the methodology. Depending on the hydrate-forming mixture considered, the percentage of absolute average deviation in predicting the hydrate equilibrium pressure is found to be in the range 3–91%, with the majority of systems having deviations that are less than 30%.

Kanokkarn Sunkonkit,1,2,&ast; Sarah Selvadurai,3,&ast; Giorge Voutsas,3 David Benzon,3 Adele Baker,1 Melissa Trinh,1 Indra Narang1,3 1Division of Respiratory Medicine, Department of Pediatrics, The Hospital for Sick Children, University of Toronto, Toronto, Canada; 2Division of Pulmonary and Critical Care, Department of Pediatrics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; 3Translational Medicine, Research Institute, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada&ast;These authors contributed equally to this workCorrespondence: Indra Narang, Division of Respiratory Medicine, The Hospital for Sick Children, 555 University Ave, Toronto, ON, M5G 1X8, Canada, Tel +1-416-813-6346, Fax +1-416-813-6246, Email indra.narang@sickkids.caPurpose: Positive airway pressure (PAP) therapy is an effective treatment prescribed to children with sleep disordered breathing (SDB); however, PAP adherence remains challenging. Given that COVID-19 pandemic continues to impact sleep and daily life, the aim of this study was to evaluate longitudinal trajectory of PAP usage in children during the COVID-19 pandemic.Patients and Methods: This was a retrospective study. Children aged 1– 18 years with SDB prescribed PAP at The Hospital for Sick Children (Toronto, Canada) were evaluated for PAP adherence. Demographics, medical history and PAP adherence data during four consecutive 3-month time periods from December 2019 to December 2020 were collected. These four time periods included i) prior to COVID-19 lockdown, ii) during the first three months of lockdown, iii) summer and iv) return to school period. Percentage of days where PAP was used for ≥ 4 hours and average nightly usage of PAP were primary outcomes.Results: A total of 149 children (61.7% male, mean (±SD) age=12.8 ± 4.1 years, BMI (±SD) z-score=1.45± 1.43) were enrolled. Compared to prior to lockdown, the median (IQR) of percentage of PAP usage ≥ 4 hours and average nightly usage of PAP declined significantly during the summer and return to school periods (p< 0.001 for all). By the end of the return to school period, only 69/149 (46%) showed sustained PAP usage and 80/149 (54%) had decreased PAP usage. Obesity was a risk factor for a decline in PAP usage after returning to school (β=− 15.36, p=0.03).Conclusion: Compared to COVID-19 pre-pandemic PAP usage, there was a significant decline in PAP usage across COVID-19 pandemic. There is critical under usage of PAP in children diagnosed with SDB, resulting in an urgent need to address barriers to mitigate poor adherence to PAP long-term. Targeted strategies are required to optimize PAP adherence in children with SDB.Keywords: COVID-19 pandemic, sleep disordered breathing, longitudinal, positive airway pressure adherence, children

Background and Objectives: The uncemented threaded DELTA ST-C cup was introduced in last few years. It has a hemispheric shell, consisting of Ti6Al4V titanium alloy. The MINIMA S stem was developed according to the principles of proximal-loading and extended metaphyseal geometry applied to a short stem. The purpose of the study was to assess the clinical and radiographic outcomes and the short- and mid-term survivorship of the DELTA ST-C cup and MINIMA S stem in patients undergoing total hip arthroplasty (THA). The present is the first study to report outcomes and implant survivorship of the DELTA ST-C cup coupled with the MINIMA S femoral stem. Materials and Methods: The present study is a retrospective observational cohort study of a prospectively maintained database, evaluating clinical outcomes and implant survivorship in 95 patients undergoing THA with the MINIMA stem coupled with the DELTA ST-C cup with at least a 3-year follow-up. The clinical evaluation was assessed with a change in the Harris hip score (HHS), while the radiographic evaluation included anteroposterior views of the pelvis and lateral views of the affected hip. Results: The enrolled population’s mean age was 69.3 years and most patients were female (64%). The MINIMA S standard stem was implanted in 68 patients (72%), the lateralized stem was implanted in 27 (28%), and the mean acetabular inclination was 48.2°. The HHS improved significantly from the preoperative value (median 46, IQR: 38–55), already at 1 month after surgery (median 76, IQR: 66–77), reaching excellent results at 1 year and 3 years postoperatively (median 96, IQR: 91–100). X-rays demonstrated good implant stability and biomechanics parameter restorations revealed no sign of subsidence, and the presence of radiolucent lines greater than 2 mm in the short stem area in five cases and in the acetabulum in one were not clinically significant. No revisions have been performed so far. Conclusions: The MINIMA S stem coupled with the DELTA ST-C cup demonstrated very good clinical and radiological results with a significant increase of the Harris hip score at short- and mid-term follow-up. This is the first study evaluating the DELTA ST-C cup, showing promising outcomes during the study’s follow-up. The MINIMA S stem has been evaluated in a very few studies. However, the combination with this particular cup had not yet been studied. The design of the stem and the cup ensures primary stability and excellent early term outcomes, moreover the study demonstrates extraordinary implant survivorship, equal to 100%.

Today’s workforce reflects and will continue to reflect diversity. If these changes represent America’s future demographic reality, organizations will undergo a massive metamorphosis. A questionnaire was submitted to 300 business students to assess their attitudes towards diversity. Specifically, it investigates whether there is a difference in attitude and assesses whether business students are open to working with an increasingly diverse workforce. The study’s results support the hypotheses that different ethnic groups value diversity differently, and that the more years living in a diverse country, the more individuals increase their diversity tolerance. Diversity, equity, and inclusion initiatives increase in popularity since they build awareness and skills that help cultivate a safe, compassionate, and equitable organizational culture where everyone feels valued. This article discusses implementing a diversity, equity, and inclusion (DEI) initiative to improve an organization’s culture. The five-step DEI Organizational Metamorphosis Model explores how to strengthen an organization’s quality of life through implementing strategic DEI initiatives. [ABSTRACT FROM AUTHOR]

Background: It is generally accepted that braces can stop curve progression but little evidence exists regarding structural improvement in the spine using spinal bracing. Our study aimed to investigate the possible structural improvements of vertebral wedging with high correction bracing. Objectives: The aim of our study was to assess whether spinal brace treatment may influence vertebral wedging in adolescent idiopathic scoliosis (AIS). Method: We reviewed our database according to the following inclusion criteria: girls with a diagnosis of AIS, Risser 0–2, age 10–14 years with Cobb angles greater than 35°. Our study cohort consisted of 27 patients fulfilling the inclusion criteria with an average brace wearing time of 16.6 h per day and Cobb angles between 36° and 79°. The target value for our study was the apical vertebra wedging, measured twice before brace treatment commenced and twice after the average follow-up period of 20.5 months of treatment. Results: The average apex wedging noted before brace wearing started was 9.8° (median: 9) and after a period of 20.5 months of brace wearing, it had reduced to an average of 5.8° (median: 4.9), (p 0.001). This would indicate a structural correction of 44%. Conclusions: Our study supports the hypothesis that spinal high correction braces improve the degree of vertebral wedging in skeletally immature girls with AIS. Clinical implications: Structural corrections of the apical vertebra seem possible when high correction asymmetric braces are used in the treatment of patients with AIS.

C. vulgaris microalgae biomass was employed for the extraction of valuable bioactive compounds with deep eutectic-based solvents (DESs). Particularly, the Choline Chloride (ChCl) based DESs, ChCl:1,2 butanediol (1:4), ChCl:ethylene glycol (1:2), and ChCl:glycerol (1:2) mixed with water at 70/30 w/w ratio were used for that purpose. The extracts’ total carotenoid (TCC) and phenolic contents (TPC), as well as their antioxidant activity (IC50), were determined within the process of identification of the most efficient solvent. This screening procedure revealed ChCl:1,2 butanediol (1:4)/H2O 70/30 w/w as the most compelling solvent; thus, it was employed thereafter for the extraction process optimization. Three extraction parameters, i.e., solvent-to-biomass ratio, temperature, and time were studied regarding their impact on the extract’s TCC, TPC, and IC50. For the experimental design and process optimization, the statistical tool Response Surface Methodology was used. The resulting models’ predictive capacity was confirmed experimentally by carrying out two additional extractions under conditions different from the experimental design.

The purpose of this action research study was to examine the effect of an adapted swimming program in terms of improving the performance and behaviour of an individual with kyphosis-scoliosis, with the use of an individualised education approach. The sample consisted of an adult woman with kyphosis-scoliosis. The pre-swimming phase included a holistic evaluation of the abilities of the individual in terms of swimming performance, measurement of the behaviour according to the Rutter Scale and physical-health variables. Next, the subject followed an adapted swimming program based on the Halliwick Method. The duration of the swimming program was 6 months at a frequency of two times per week, for 60 minutes. Each session included additional muscle strength and body posture exercises outside water. At the end of the swimming program the initial measurements were repeated. The results of the study revealed the beneficial effect of the swimming lessons in terms of improving the swimming abilities and the behaviour of the individual. In the light of the findings, useful conclusions were drawn regarding the structure of the swimming program. (Contains 3 tables.)

The recovery of phenolic compounds from olive leaves (Olea europaea L.) has received special attention due to their significant potential for applications in food, nutraceuticals, cosmetics, and pharmaceuticals. In this work, the extraction of the phenolic compounds from olive leaves was examined by means of conventional extraction and microwave-assisted extraction (MAE) using nontoxic common solvents such as ethanol and water as well as using promising environmentally friendly, Deep Eutectic Solvents (DESs) and their mixtures with ethanol or water. The effects of the various parameters that likely govern the extractability of the bioactive compounds of olive leaves (OL), such as the solvent type, temperature, and biomass to solvent mass ratio, were studied and evaluated with regard to the oleuropein and hydroxytyrosol content, antioxidant activity, and total phenolic content of the extracts. The study also explores the effects of the microwave-assisted extraction parameters, namely irradiation power and time, on the total phenolic content and antioxidant activity of the extracts. The findings of this work suggest that among the solvents studied, the solvent mixture consisting of the DES choline chloride:acetic acid with a molar ratio of 1:2 and ethanol (80:20 w/w) is highly effective in recovering extracts rich in phenolic compounds and with significant antioxidant activity. Moreover, it is demonstrated that the MAE method allows for the recovery of bioactive compounds in a very short processing time.

The enzymes that belong to the aldehyde dehydrogenase family are expressed in a variety of cells; yet activity of their main members characterizes stem cells, both normal and malignant. Several members of this family perform critical functions in stem cells, in general, and a few have been shown to have key roles in malignant tumors and their recurrence. In particular, ALDH1A1, which localizes to the cytosol and the nucleus, is an enzyme critical in cancer stem cells. In acute myeloid leukemia (AML), ALDH1A1 protects leukemia-initiating cells from a number of antineoplastic agents, and proves vital for the establishment of human AML xenografts in mice. ALDH2, which is located in mitochondria, has a major role in alcohol metabolism by clearing ethanol-derived acetaldehyde. Haematopoietic stem cells require ALDH2 for protection against acetaldehyde, which can cause damage to DNA, leading to insertions, deletions, chromosomal rearrangements, and translocations. Mutations compromise stem cell function, and thereby threaten blood homeostasis. We review here the potential of targeting the enzymatic activity of aldehyde dehydrogenases in acute leukemia.

Macroalgae Ulva lactuca, has been employed as a natural source for the production of extracts with potent bioactivity. The biochemical characterization showed that the macroalgae biomass contains a remarkable amount of the polysaccharide Ulvan (49.9 wt%) which is a valuable chemical compound well known for its benefits in human health. Four nontoxic solvents, water, ethyl acetate, ethanol, and an ethanol/water mixture (70:30 v/v) were examined for their recovery efficiency of total carotenoid and phenolic contents. Experimental results showed that the aqueous mixture of ethanol was the most efficient solvent in the recovery of bioactive compounds with extraction yield of 10–15% dw. The effect of extraction parameters, namely time, temperature, and the ratio of biomass to solvent, on the carotenoid and phenolic compounds’ content, antioxidant activity, and extraction yield, was investigated, using the ethanol/water mixture as a solvent. The extract obtained under 60 °C, 3 h of extraction time and 1:10 biomass to solvent mass ratio showed the highest antioxidant activity. This extract maintained its antioxidant capacity almost stable for five days of storage under cool and dark conditions. Finally, specific phenolic and carotenoid compounds in the U. lactuca extracts were identified using the High-Performance Liquid Chromatography (HPLC) technique.

Microalgae contain an abundance of valuable bioactive compounds such as chlorophylls, carotenoids, and phenolics and, consequently, present great commercial interest. The aim of this work is the study and optimization of recovering the aforementioned components from the microalgae species Chlorella vulgaris through conventional extraction in a laboratory-scale apparatus using a “green” mixture of ethanol/water 90/10 v/v. The effect of three operational conditions—namely, temperature (30–60 °C), duration (6–24 h) and solvent-to-biomass ratio (20–90 mLsolv/gbiom), was examined regarding the extracts’ yield (gravimetrically), antioxidant activity, phenolic, chlorophyll, and carotenoid contents (spectrophotometric assays), as well as concentration in key carotenoids, i.e., astaxanthin, lutein, and β-carotene (reversed-phase–high-performance liquid chromatography (RP–HPLC)). For this purpose, a face-centered central composite design (FC-CCD) was employed. Data analysis resulted in the optimal extraction conditions of 30 °C, for 24 h with 37 mLsolv/gbiom and validation of the predicted models led to 15.39% w/w yield, 52.58 mgextr/mgDPPH (IC50) antioxidant activity, total phenolic, chlorophyll, and carotenoid content of 18.23, 53.47 and 9.92 mg/gextr, respectively, and the total sum of key carotenoids equal to 4.12 mg/gextr. The experimental data and predicted results were considered comparable, and consequently, the corresponding regression models were sufficiently reliable for prediction.

Harvesting of microalgae is a crucial step in microalgae-based mass production of different high value-added products. In the present work, magnetic harvesting of Chlorella vulgaris was investigated using microwave-synthesized naked magnetite (Fe3O4) particles with an average crystallite diameter of 20 nm. Optimization of the most important parameters of the magnetic harvesting process, namely pH, mass ratio (mr) of magnetite particles to biomass (g/g), and agitation speed (rpm) of the C. vulgaris biomass–Fe3O4 particles mixture, was performed using the response surface methodology (RSM) statistical tool. Harvesting efficiencies higher than 99% were obtained for pH 3.0 and mixing speed greater or equal to 350 rpm. Recovery of magnetic particles via detachment was shown to be feasible and the recovery particles could be reused at least five times with high harvesting efficiency. Consequently, the described harvesting approach of C. vulgaris cells leads to an efficient, simple, and quick process, that does not impair the quality of the harvested biomass.