This study aims to explore the association of hospital infection prevention and control (IPC) structure (i.e. a dedicated IPC team and/or IPC committee) and IPC capacity in Korean hospitals, as well ...as its implications in the response and preparedness to COVID-19.
This was a cross-sectional study using data collected through a nationwide survey.
Participating hospitals completed an online questionnaire. Participation was voluntary. The survey questionnaire was developed by the government in consultation with IPC experts. The questionnaire was distributed to 2108 hospitals, including both acute and long-term care hospitals. The independent variables were the presence of an IPC team and/or IPC committee. The dependent variables were IPC activities and capacity measures, which were based on the World Health Organisation (WHO) recommendations on the core components in IPC.
A total of 1442 hospitals completed the survey. Hospitals with IPC structures conducted significantly more IPC activities in all outcome measures compared with hospitals without IPC structures, with the exceptions of monitoring hand hygiene and screening for infectious diseases that showed non-significant differences. Hospitals with IPC structures showed a significant difference in performance in IPC risk assessment, operating outbreak response teams and appraisal of hospital IPC policies compared with hospitals without IPC structures.
The presence of a dedicated IPC team and IPC committee was associated with increased IPC activities and IPC capacity. Hospitals with IPC teams and IPC committees showed strong implementation of planning, appraisal, resource management and outbreak response, indicating that strengthening IPC structures within hospitals is the key to more effective IPC and disaster response.
Aims
Microbial consortia can be more efficient at biological processes than single isolates. The purposes of this study were to design and evaluate a synthetic microbial consortium containing the ...methanotroph Methylocystis sp. M6 and the helper Hyphomicrobium sp. NM3, and develop a novel methanotrophic process for this consortium utilizing a dialysis membrane.
Methods and Results
Hyphomicrobium increased the methane‐oxidation rate (MOR), biomass and stability at a dilution rate of 0·067 day−1 in fed‐batch co‐culture. qRT‐PCR showed that Methylocystis population increased gradually with time, whereas Hyphomicrobium population remained stable despite cell washing, confirming synergistic population interaction. At 0·1 day−1, spiking of Hyphomicrobium effectively increased the methanotrophic activity, after which Hyphomicrobium population decreased with time, indicating that the consortium is optimal at <0·1 day−1. When Hyphomicrobium was grown in dialysis membrane within the bioreactor, MOR increased linearly up to 155·1 ± 1·0 mmol l−1 day−1 at 0·067, 0·1, 0·2 and 0·4 day−1, which is the highest observed value for a methanotrophic reactor.
Conclusions
Hyphomicrobium sp. NM3 is a promising helper micro‐organism for methanotrophs. Hyphomicrobium‐methanotroph consortia used concurrently with existing methods can produce an efficient and stable methane oxidation system.
Significance and Impact of the Study
This novel methanotrophic process is superior to those previously reported in the literature, and can provide efficient and stable methane oxidation.
The use of semiconducting metal oxides to develop highly sensitive CO2 chemi-resistive sensing systems remains an important scientific challenge in the field of gas sensing. In this work, we describe ...the synthesis, characterization, and application of a very important CO2 gas sensing material ZnO-loaded with different atomic percentages of La prepared by a simple hydrothermal method. Synthesized samples were structurally and thermally characterized. The CO2 sensing characteristics of pure ZnO and La-loaded ZnO were compared using a homemade gas sensing measurement system. The sensitivity, operating temperature, and response/recovery time were systematically investigated based on the change in electrical resistance of the materials in the presence of CO2. Experimental results confirmed that 50at% La-loaded ZnO showed a maximum response to 5000ppm CO2 (65%) at an operating temperature of 400°C. The sensing mechanism of the pure and La-loaded ZnO nanopowders is discussed in detail. We believed that the La-loaded, flower-like ZnO nanopowder offers a potential platform for semiconductor-oxide-based CO2 gas sensors.
Selectivity--the production of one molecule out of many other thermodynamically feasible product molecules--is the key concept in developing clean processes that do not produce by-products (green ...chemistry). Small differences in the potential-energy barriers of single reaction steps control which reaction channel is more likely to yield the desired product molecule (selectivity), while the overall activation energy of the reaction controls the turnover rates (activity). Recent studies have demonstrated that tailoring parameters at the atomic or molecular level--such as the surface structures of active sites--gives turnover rates and reaction selectivities that depend on the nanoparticle size and shape. Here, we highlight seven molecular components that influence the selectivity of heterogeneous catalyst reactions on single-crystal model surfaces and colloid nanoparticles: surface structure, adsorbate-induced restructuring, adsorbate mobility, reaction intermediates, surface composition, charge transport, and oxidation states. We show the importance of the single factors by means of examples and describe in situ analyses that permit their roles in surface reactions to be investigated.
•Indirect extrusion was used for microstructural refinement in Mg–Ca alloys.•Corrosion resistance was tested in the Hank’s solution.•Corrosion rates of Mg–Ca alloys (2–3Ca%) greatly decreased after ...extrusion.•Refining of Mg2Ca phase is important for enhancement of corrosion resistance.
The effect of indirect extrusion on microstructural refinement, mechanical properties and corrodibility of the pure Mg and Mg–Ca alloys (up to 3wt.% Ca) in Hank’s solution has been systematically studied. After extrusion, mechanical properties including tensile strength and ductility, and corrosion resistance of the Mg–Ca alloys were greatly enhanced in the Mg–Ca alloys with Ca⩾1%. Effective break-up of (semi-)continuous secondary phase (Mg2Ca) existing along grain boundaries or interdendritic regions during extrusion played a critical role in enhancement of the corrosion resistance of the Mg–Ca alloys with Ca⩾1% compared to the as-cast counterparts.
Cloning, through somatic cell nuclear transfer (SCNT), has the potential for a large expansion of genetically favorable traits in a population in a relatively short term. In the present study we ...aimed to produce multiple cloned camels from racing, show and dairy exemplars. We compared several parameters including oocyte source, donor cell and breed differences, transfer methods, embryo formation and pregnancy rates and maintenance following SCNT. We successfully achieved 47 pregnancies, 28 births and 19 cloned offspring who are at present healthy and have developed normally. Here we report cloned camels from surgical embryo transfer and correlate blastocyst formation rates with the ability to achieve pregnancies. We found no difference in the parameters affecting production of clones by camel breed, and show clear differences on oocyte source in cloning outcomes. Taken together we demonstrate that large scale cloning of camels is possible and that further improvements can be achieved.
The challenge of chemistry in the 21st century is to achieve 100% selectivity of the desired product molecule in multipath reactions (“green chemistry”) and develop renewable energy based processes. ...Surface chemistry and catalysis play key roles in this enterprise. Development of in situ surface techniques such as high-pressure scanning tunneling microscopy, sum frequency generation (SFG) vibrational spectroscopy, time-resolved Fourier transform infrared methods, and ambient pressure X-ray photoelectron spectroscopy enabled the rapid advancement of three fields: nanocatalysts, biointerfaces, and renewable energy conversion chemistry. In materials nanoscience, synthetic methods have been developed to produce monodisperse metal and oxide nanoparticles (NPs) in the 0.8−10 nm range with controlled shape, oxidation states, and composition; these NPs can be used as selective catalysts since chemical selectivity appears to be dependent on all of these experimental parameters. New spectroscopic and microscopic techniques have been developed that operate under reaction conditions and reveal the dynamic change of molecular structure of catalysts and adsorbed molecules as the reactions proceed with changes in reaction intermediates, catalyst composition, and oxidation states. SFG vibrational spectroscopy detects amino acids, peptides, and proteins adsorbed at hydrophobic and hydrophilic interfaces and monitors the change of surface structure and interactions with coadsorbed water. Exothermic reactions and photons generate hot electrons in metal NPs that may be utilized in chemical energy conversion. The photosplitting of water and carbon dioxide, an important research direction in renewable energy conversion, is discussed.
Aims
Recovering DNA of airborne micro‐organisms (AM) from air is a challenging task. We compared five membrane filters for bioaerosol sampling—mixed cellulose ester (MCE), polyethersulfone (PES), ...polyamide (PA), polytetrafluorethylene (PTFE) and polyvinylidene fluoride (PVDF)—based on their bacterial, fungal and eukaryotic DNA recoveries.
Methods and results
Bacterial, fungal and eukaryotic populations were quantified using quantitative PCR. With a bacterial consortium, PTFE exhibited the best recovery efficiency (113%), followed by PA (92%), PES (86%), MCE (48%) and PVDF (1%). When filters were compared with air, PA was used as a control to normalize results from the others. The bacterial, fungal and eukaryotic DNA recovery ratios were markedly greater in PES (9·3, 11·5 and 10·3 respectively) than in the remaining. Eukaryotic MiSeq sequencing revealed that PES recovered a more diverse and considerably richer assemblage (richness ratios, 4·97 vs ≤ 1·16 for PES vs the others). Rank abundance distribution analysis showed that distribution tails were longer (>4 times) in PES, but these did not differ between the remaining and PA. Community comparison showed that PES exhibited a lower variation across trials than the PA, while the remaining did not.
Conclusions
PES filter markedly outperformed the other filters in quantitative and qualitative recovery of AM.
Significance and Impact of the Study
Our findings demonstrated the importance of filter selection for sampling AM.
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