Covalent Immobilization of Aldehyde and Alcohol Dehydrogenases on Ordered Mesoporous Silicas

Purpose This work studies the immobilization of two enzymes, the alcohol dehydrogenase (ADH) and the aldehyde dehydrogenase (AldDH) both from Saccharomyces cerevisiae, which could be used to produce high value-added molecules from carboxylic acids embedded in anaerobic digestate.Methods In particular, three mesoporous siliceous materials, with different specific surface areas and pore sizes, (MSU-H, MSU-F and MCF0.75) were used as supports for covalent immobilization. The support materials were characterized by complementary techniques. Then, after a functionalization, creating a covalent bond between the enzyme and the support was performed. The specific activity and immobilization yield of the biocatalysts were then evaluated.Results The best results were obtained with MSU-H and MSU-F, resulting in an immobilization yield greater than 50% in all cases, a specific activity of 0.13 IU/g(supp) with the AldDH/MSU-H, 0.10 IU/g(supp) with AldDH/MSU-F, 48.6 IU/g(supp) with ADH/MSU-H and 12.6 IU/g(supp) with ADH/MSU-H. These biocatalysts were then characterized by optimal pH and temperature and the stability factor was evaluated. With ADH/MSU-F no decrease in activity was observed after 120 h incubated at 50 degrees C. Finally, the biocatalysts AldDH/MSU-H and ADH/MSU-H were used to perform the reduction reaction and it was seen that after five reaction cycles the residual activity was greater than 20% in both cases.Conclusion The ADH and AldDH enzymes have been successfully immobilized on mesoporous siliceous supports, considerably increasing their thermal stability and being able to reuse them for several reaction cycles. The use of this immobilization and these supports is adaptable to a wide variety of enzymes

Estimation of Excess Mortality Rates Among US Assisted Living Residents During the COVID-19 Pandemic.

The devastating effects of COVID-19 among older adults residing in long-term care settings have been well documented.1 Although much attention has been paid to COVID-19–associated mortality in nursing homes,2 less is understood about its effects on assisted living residents. Most assisted living residents are aged 80 years or older and many have multiple chronic illnesses, making them highly susceptible to poor outcomes of COVID-19.3 This study examines the excess mortality among a US cohort of assisted living residents during the COVID-19 pandemic

Atmospheric chemistry regimes in intercontinental air traffic corridors:Ozone versus NOx sensitivity

This study focusses on the environmental consequences of aircraft NOx emissions and their role and impact on ozone formation in the upper troposphere and lower stratosphere (UTLS). We use a global chemistry transport/box model approach to quantify the impacts of NOx on UTLS ozone over time scales of hours and over distance scales appropriate to air traffic corridors and aircraft flight paths. An important feature of our study has been to provide a marked contrast to the coarse spatial resolution of the global model studies typically employed to assess the impacts of aviation NOx on UTLS ozone. Real operational aviation routing data are used to quantify the NOx impacts on ozone at 235 locations on 21 flight paths. The NOx impact on ozone in the intercontinental air traffic corridors is strongest in the great circle routes from North America and Europe into Asia and weakest in the trans-polar routes. The NOx impacts identified with the CTM/box model combination are significantly smaller compared with those identified in the current global models typically used to assess aviation NOx impacts. Further research is required to confirm our assessment of those flight paths that appear to show greatest NOx – O3 impacts and those the least and extend our analyses into the tropics and southern hemisphere

Cerium‐Copper Oxides Synthesized in a Multi‐Inlet Vortex Reactor as Effective Nanocatalysts for CO and Ethene Oxidation Reactions

In this study, a set of CuCeOx catalysts was prepared via the coprecipitation method using a Multi‐Inlet Vortex Reactor: the Cu wt.% content is 5, 10, 20, 30 and 60. Moreover, pure CeO2 and CuO were synthesized for comparison purposes. The physico‐chemical properties of this set of samples were investigated by complementary techniques, e.g., XRD, N2 physisorption at −196 °C, Scanning Electron Microscopy, XPS, FT‐IR, Raman spectroscopy and H2‐TPR. Then, the CuCeOx catalysts were tested for the CO and ethene oxidation reactions. As a whole, all the prepared samples presented good catalytic performances towards the CO oxidation reaction (1000 ppm CO, 10 vol.% O2/N2): the most promising catalyst was the 20%CuCeOx (complete CO conversion at 125 °C), which exhibited a long‐term thermal stability. Similarly, the oxidative activity of the catalysts were evaluated using a gaseous mixture containing 500 ppm C2H4, 10 vol.% O2/N2. Accordingly, for the ethene oxidation reaction, the 20%CuCeOx catalyst evidenced the best catalytic properties. The elevated catalytic activity towards CO and ethene oxidation was mainly ascribed to synergistic interactions between CeO2 and CuO phases, as well as to the high amount of surface‐chemisorbed oxygen species and structural defects

Association Between State Regulations Supportive of Third-party Services and Likelihood of Assisted Living Residents in the US Dying in Place

Importance Older adults are increasingly residing in assisted living residences during their last year of life. The regulations guiding these residential care settings differ between and within the states in the US, resulting in diverse policies that may support residents who wish to die in place. Objective To examine the association between state regulations and the likelihood of assisted living residents dying in place. The study hypothesis was that regulations supporting third-party services, such as hospice, increase the likelihood of assisted living residents dying in place. Design, Setting, and Participants This retrospective cohort study combined data about assisted living residences in the US from state registries with an inventory of state regulations and administrative claims data. The study participants comprised 168 526 decedents who were Medicare beneficiaries, resided in 8315 large, assisted living residences (with ≥25 beds) across 301 hospital referral regions during the last 12 months of their lives, and died between 2017 and 2019. Descriptive analyses were performed at the state level, and 3-level multilevel models were estimated to examine the association between supportive third-party regulations and dying in place in assisted living residences. The data were analyzed from September 2021 to August 2022. Exposures Supportive (vs “silent,” ie, not explicitly mentioned in regulatory texts) state regulations regarding hospice care, private care aides, and home health services, as applicable to licensed/registered assisted living residences across the US. Main Outcomes and Measures Presence in assisted living residences on the date of death. Results The median (IQR) age of the 168 526 decedents included in the study was 90 (84-94) years. Of these, 110 143 (65.4%) were female and 158 491 (94.0%) were non-Hispanic White. Substantial variation in the percentage of assisted living residents dying in place was evident across states, from 18.0% (New York) to 73.7% (Utah). Supportive hospice and home health regulations were associated with a higher odds of residents dying in place (adjusted odds ratio [AOR], 1.38; 95% CI, 1.24-1.54; P \u3c .001; and AOR, 1.21; 95% CI, 1.10-1.34; P \u3c .001, respectively). In addition, hospice regulations remained significant in fully adjusted models (AOR, 1.46; 95% CI, 1.25-1.71). Conclusions and Relevance The findings of this cohort study suggest that a higher percentage of assisted living residents died in place in US states with regulations supportive of third-party services. In addition, assisted living residents in licensed settings with regulations supportive of hospice regulations were especially likely to die in place

National trends in the treatment of urinary tract infections among Veterans’ Affairs Community Living Center residents

Objective: To describe urinary tract infection (UTI) treatment among Veterans’ Affairs (VA) Community Living Centers (CLCs) nationally and to assess related trends in antibiotic use. Design: Descriptive study. Setting and participants: All UTI episodes treated from 2013 through 2017 among residents in 110 VA CLCs. UTI episodes required collection of a urine culture, antibiotic treatment, and a UTI diagnosis code. UTI episodes were stratified into culture-positive and culture-negative episodes. Methods: Frequency and rate of antibiotic use were assessed for all UTI episodes overall and were stratified by culture-positive and culture-negative episodes. Joinpoint software was used for regression analyses of trends over time. Results: We identified 28,247 UTI episodes in 14,983 Veterans. The average age of Veterans was 75.7 years, and 95.9% were male. Approximately half of UTI episodes (45.7%) were culture positive and 25.7% were culture negative. Escherichia coli was recovered in 34.1% of culture-positive UTI episodes, followed by Proteus mirabilis and Klebsiellaspp, which were recovered in 24.5% and 17.4% of culture-positive UTI episodes, respectively. The rate of total antibiotic use in days of therapy (DOT) per 1,000 bed days decreased by 10.1% per year (95% CI, −13.6% to −6.5%) and fluoroquinolone use (ciprofloxacin or levofloxacin) decreased by 14.5% per year (95% CI, −20.6% to −7.8%) among UTI episodes overall. Similar reductions in rates of total antibiotic use and fluoroquinolone use were observed among culture-positive UTI episodes and among culture-negative UTI episodes. Conclusion: Over a 5-year period, antibiotic use for UTIs significantly decreased among VA CLCs, as did use of fluoroquinolones. Antibiotic stewardship efforts across VA CLCs should be applauded, and these efforts should continue