ABSTRACT
Halide solid electrolytes (SEs) have been highlighted for their high-voltage stability. Among the halide SEs, the ionic conductivity has been improved by aliovalent metal substitutions or choosing a ccp-like anion-arranged monoclinic structure (C2/m) over hcp- or bcc-like anion-arranged structures. Here, we present a new approach, hard-base substitution, and its underlying mechanism to increase the ionic conductivity of halide SEs. The oxygen substitution to Li2ZrCl6 (trigonal, hcp) increased the ionic conductivity from 0.33 to 1.3 mS cm-1 at Li3.1ZrCl4.9O1.1 (monoclinic, ccp), while the sulfur and fluorine substitutions were not effective. A systematic comparison study revealed that the energetic stabilization of interstitial sites for Li migration plays a key role in improving the ionic conductivity, and the ccp-like anion sublattice is not sufficient to achieve high ionic conductivity. We further examined the feasibility of the oxyhalide SE for practical and all-solid-state battery applications.
ABSTRACT
This study examined and verified the level of e-health literacy (e-HL) and infection preventive behaviors related to COVID-19 among undergraduate students majoring in healthcare. An online survey was conducted with 274 university students majoring in nursing, clinical pathology, and occupational therapy in South Korea. The e-HL consisted of functional, communicational, and critical literacy, and preventive behaviors were based on the Prevention Guideline on Droplet Infection. The mean score for e-HL was 3.62, with nursing students obtaining the highest scores. The overall e-HL score and the scores on its three sub-dimensions were related to infection-preventive behaviors. Moreover, e-HL affected infection-preventive behaviors (p < 0.001). Findings from this study highlight the necessity of education for improving the e-HL of undergraduate students majoring in healthcare to strengthen infection-preventive behaviors and protect patients from infectious diseases.
ABSTRACT
A fed-batch bioreactor based on sulfur-oxidizing bacteria (SOB) was tested for rapid detection of heavy metal-induced toxicity in water. For this evaluation, SOB were exposed to water contaminated by selenium, mercury, hexavalent chromium, arsenic, cyanide, cadmium, and lead for 2â¯h and their inhibition rates were analyzed based on changes in electrical conductivity (EC). The results demonstrate that SOB were highly inhibited by selenium, mercury, hexavalent chromium, and arsenic but not by cyanide, cadmium, and lead. The 2â¯h half maximum effective concentrations (EC50) of SOB for selenium, mercury, hexavalent chromium, and arsenic were estimated to be 0.33, 0.89, 1.18, and 0.24â¯mg/L, respectively, which are comparable or lower than earlier reports in the literature. However, the EC50 or EC20 values of SOB for cyanide, cadmium, and lead were notably higher compared to findings from previous toxicity tests that employed other microorganisms. The findings from the current study suggest that the fed-batch SOB bioreactor is suitable for rapid detection of toxicity induced by selenium, mercury, hexavalent chromium, and arsenic in water.
Subject(s)
Bacteria/metabolism , Batch Cell Culture Techniques/methods , Metals, Heavy/analysis , Sulfur/metabolism , Toxicity Tests/methods , Water Pollutants, Chemical/isolation & purification , Water/chemistry , Batch Cell Culture Techniques/instrumentation , Bioreactors , Cadmium/analysis , Chromium , Electric Conductivity , Environmental Monitoring/methods , Oxidation-Reduction , Water Pollutants, Chemical/chemistryABSTRACT
The toxicities of Cr (III) and Cr (VI) in water were evaluated using sulfur-oxidizing bacterial (SOB) bioassays both in batch and fed-batch conditions. Two days were enough for a quick buildup of SOB consortium in the master culture reactor (MCR). At concentrations up to 100 mg L(-1), Cr (III) was found to be nontoxic in both conditions, while Cr (VI) at very low concentrations (0.1-2 mg L(-1)) was very toxic to the SOB. Literature review suggested that the nontoxic nature of Cr (III) might be due to the absence of the iron uptake pathway in Acidithiobacillus caldus (the predominant bacteria in our reactors), which is required for Cr (III) uptake. The 2-h median effective concentration (EC50) values obtained for Cr (VI) in the batch and fed-batch tests were 2.7 mg L(-1) and 1.5 mg L(-1), respectively.
Subject(s)
Acidithiobacillus/drug effects , Chlorides/toxicity , Chromium Compounds/toxicity , Chromium/toxicity , Environmental Monitoring/methods , Water Pollutants, Chemical/toxicity , Acidithiobacillus/growth & development , Acidithiobacillus/metabolism , Biological Assay , Chlorides/chemistry , Chromium/chemistry , Chromium Compounds/chemistry , Iron/metabolism , Oxidation-Reduction , Sulfur/metabolism , Water Pollutants, Chemical/chemistryABSTRACT
Intraoperative transesophageal echocardiography (TEE) has become an important monitoring device for patients undergoing cardiac or noncardiac surgery. Complications associated with TEE are unusual, but the potential for TEE probe compression of the posterior vascular structures has been reported in pediatric patients. We present here a case of occlusion of the right subclavian artery in an adult patient with a vascular ring after insertion of a TEE probe.
