An easily recoverable thermo-sensitive polyelectrolyte as draw agent for forward osmosis process

As a potential solution to the crises of energy and resources, forward osmosis(FO) has been limited by the development of draw agents. An ideal draw agent should be able to generate high osmotic pressure and can be easily recovered. In this study, a thermo-sensitive polyelectrolyte of poly(N-isopropylacrylamide-co-acrylic acid)(PNA)is developed as an efficient draw agent, and two easy and simple methods are proposed to effectively recover the polyelectrolytes. After adjusting the pH value of polyelectrolyte solutions to around 6.0, the polyelectrolyte can generate relatively high osmotic pressure, and induce average water fluxes of 2.09 and 2.95 L·m^(-2)·h^(-1) during12 h FO processes when the polyelectrolyte concentrations are 0.20 and 0.38 g·ml^(-1) respectively. After acidifying and heating to 70 °C, the PNA-10 polyelectrolyte can aggregate together because of hydrophobic association and separate from water, so it can be easily recovered by either simple centrifugation or gravitational sedimentation. The recovery ratios of PNA-10 polyelectrolyte in both methods are as high as 89%, and the recovered polyelectrolytes can be reused with almost the same FO performance as fresh ones. The results in this study provide valuable guidance for designing efficient and easily recoverable draw agents for FO processes.

Oxygen uptake response to switching stairs exercise by non-parametric modeling

Oxygen uptake plays a crucial role in the evaluation of endurance performance during exercise and is extensively utilized for metabolic assessment. This study records the oxygen uptake during the exercise phase (i.e., ascending or descending) of the stair exercise, utilizing an experimental dataset that includes ten participants and covers various exercise periods. Based on the designed experiment protocol, a non-parametric modeling method with kernel-based regularization is generally applied to estimate the oxygen uptake changes during the switching stairs exercise, which closely resembles daily life activities. The modeling results indicate the effectiveness of the non-parametric modeling approach when compared to fixed-order models in terms of accuracy, stability, and compatibility. The influence of exercise duration on estimated fitness reveals that the model of the phase-oxygen uptake system is not time-invariant related to respiratory metabolism regulation and muscle fatigue. Consequently, it allows us to study the humans’ conversion mechanism at different metabolic rates and facilitates the standardization and development of exercise prescriptions.

Targeted gene panel provides advantages over whole-exome sequencing for diagnosing obesity and diabetes mellitus

A small fraction of patients diagnosed with obesity or diabetes mellitus has an underlying monogenic cause.Here,we constructed a targeted gene panel consisting of 83 genes reported to be causative for monogenic obesity or diabetes.We performed this panel in 481 patients to detect causative variants and compared these results with whole-exome sequencing(WES)data available for 146 of these patients.The coverage of targeted gene panel sequencing was significantly higher than that of WES.The diagnostic yield in patients sequenced by the panel was 32.9%with subsequent WES leading to three additional diagnoses with two novel genes.In total,178 variants in 83 genes were detected in 146 patients by targeted sequencing.Three of the 178 variants were missed by WES,although the WES-only approach had a similar diagnostic yield.For the 335 samples only receiving targeted sequencing,the diagnostic yield was 32.2%.In conclusion,taking into account the lower costs,shorter turnaround time,and higher quality of data,targeted sequencing is a more effective screening method for monogenic obesity and diabetes compared to WES.Therefore,this approach could be routinely established and used as a first-tier test in clinical practice for specific patients.