Colorimetric CO2 Indicators.

Carbon dioxide, CO2, is an essential part of life, in that through green plant photosynthesis it is used to generate food and fuel and is generated in both aerobic and anaerobic respiration. Industrially, it is used in fire extinguishers, supercritical fluid extractions, and food packaging. Environmentally, it is in the atmosphere, hydrosphere, and biosphere and is responsible for global warming and the acidification of the oceans. The monitoring of CO2 in the gas phase is usually carried out using FTIR spectroscopy, whereas the measurement of dissolved CO2 usually involves an electrochemical device. Excitingly, the most recent forms of CO2 indicators appear to offer significant advantages over current methods, such as simplicity, low cost, and portability. This Account highlights the work of the Mills group on transforming CO2 colorimetric indicator technology from the usual water-based (i.e., "wet") indicator form to dry CO2-sensitive inks, pigments, plastics, and adhesives. Initially, the basic theory associated with colorimetric CO2 indicators is described, and the simple relationship between indicator absorbance and the partial pressure of CO2, PCO2, established. The early work on CO2-sensitive inks is then described, where such inks comprise a hydrophilic pH-sensitive dye anion, coupled with a lipophilic quaternary ammonium cation, dissolved in a nonaqueous solution of a polymer which, when cast, forms a dry ink film that gives a reversible color response when exposed to CO2 both in the gas phase and dissolved in solution. The ability to tune the sensitivity of a CO2 ink film to the desired application through the judicious choice of the pH indicator dye and base concentration is described. The dependence of the sensitivity of a CO2 ink film on temperature is used to create a temperature indicator, and the ability to tune the ink, to respond to high levels of CO2, is used to create a fizziness indicator for carbonated drinks. Very sensitive CO2 inks are used to make a vacuum and a general air-pressure indicator. The more recent development in CO2 indicator technology is described in which CO2 inks are used to coat silica particles to make a range of different CO2-sensitive pigments, which, when incorporated into a plastic, through extrusion, produce a range of novel CO2-sensitive plastic films that have many notable advantages over their ink film counterparts. Examples are then given of such plastic films being used for dissolved CO2 measurements in salt water, for food packaging, and as an early wound-infection indicator. Finally, the recent incorporation of a CO2-sensitive pigment into a pressure sensitive adhesive to make an after opening freshness tape is described briefly. Although most commercial CO2 indicators are assessed by eye and so are limited to qualitative analysis, this work shows that colorimetric CO2 indicators can be used for quantitative analysis through absorbance measurements. Nowadays, such measurements can be readily made using just a digital camera and color analysis software via digital camera colorimetry, DCC, which is likely to have a significant impact on the widespread use of the CO2 indicators described herein, their commercial viability, and their potential areas of application.

A crossover pilot trial of the feasibility, acceptability, and effectiveness of LoveYourBrain Yoga for community-dwelling adults with multiple sclerosis.

BACKGROUND AND PURPOSE: Among people with multiple sclerosis (MS), yoga has potential to improve fatigue and other symptoms that undermine quality of life. The aim of this study was to assess the feasibility, acceptability, and effectiveness of LoveYourBrain Yoga, a six-week yoga with psychoeducation program, on fatigue and other health-related outcomes among people with MS in a rural, community-based setting in the United States. METHODS: This non-randomized 2x2 crossover pilot trial compared LoveYourBrain Yoga to a control among 15 people with MS. People were eligible if they were adults with MS (EDSS score ≤6), English-speaking, and ambulatory. Paired t-tests and Wilcoxon signed rank sum analyses assessed mean differences in PROMIS-FatigueMS, Multiple Sclerosis Impact Scale, Symbol Digit Modalities Test, NIH Neuro-QoL measures, and Liverpool Self-Efficacy scale. We assessed feasibility using recruitment and retention rates, mean attendance, fidelity, and acceptability using satisfaction measures. RESULTS: Significant improvements in fatigue (MD -4.34, SD 5.26, p = 0.012), positive affect and wellbeing (MD 2.76, SD 3.99, p = 0.028), and anxiety (MD -4.42, SD 5.36, p = 0.012) were found after LoveYourBrain Yoga compared to the control. Participants reported high satisfaction (M 9.5, SD 1.4) and a majority (92.3%) reported 'Definitely, yes' to recommending it to a friend or family. CONCLUSION: LoveYourBrain Yoga is feasible and acceptable when implemented in a rural, community-based setting for people with MS. It may improve a range of MS symptoms and offer a means for acquiring new skills for stress reduction, anxiety management, and overall wellbeing.

Characteristics and Outcomes of Patients Discharged Directly Home From a Medical Intensive Care Unit: A Retrospective Cohort Study.

OBJECTIVE: To evaluate the safety of directly discharging patients home from the medical intensive care unit (MICU). MATERIALS AND METHODS: Single-center retrospective observational study of consecutive MICU direct discharges to home from an urban university hospital between June, 1, 2017, and June 30, 2019. RESULTS: Of 1061 MICU discharges, 331 (31.2%) patients were eligible for analysis. Patients were divided into 2 groups based on duration of wait-time (< or ≥24 hours) between ward transfer order and ultimate hospital discharge. Most patients (68.2%) were discharged in <24 hours. Patients who waited for a floor bed for ≥24 hours prior to discharge had longer hospital length-of-stay (LOS, median 3.83 versus 2.00 days) and ICU LOS (median 3.51 versus 1.74 days). Overall, 44 (13.3%) direct MICU discharges were readmitted to the hospital within 30-days, but there was no difference in this outcome or in 30-day mortality when comparing the 2 wait-time groups. CONCLUSIONS: The practice of directly discharging MICU patients home does not negatively influence patient outcomes. Patients who overstay in the ICU after being deemed transfer-ready are unlikely to be benefiting from critical care, but impact hospital throughput and resource utilization. Prospective investigation into this practice may provide further confirmation of its feasibility and safety.

Assessment of Imputation Methods for Missing Gene Expression Data in Meta-Analysis of Distinct Cohorts of Tuberculosis Patients.

The growth of publicly available repositories, such as the Gene Expression Omnibus, has allowed researchers to conduct meta-analysis of gene expression data across distinct cohorts. In this work, we assess eight imputation methods for their ability to impute gene expression data when values are missing across an entire cohort of Tuberculosis (TB) patients. We investigate how varying proportions of missing data (across 10%, 20%, and 30% of patient samples) influence the imputation results, and test for significantly differentially expressed genes and enriched pathways in patients with active TB. Our results indicate that truncating to common genes observed across cohorts, which is the current method used by researchers, results in the exclusion of important biology and suggest that LASSO and LLS imputation methodologies can reasonably impute genes across cohorts when total missingness rates are below 20%.