Antimicrobial Use in COVID-19 Patients in the First Phase of the SARS-CoV-2 Pandemic:A Scoping Review

This scoping review provides new evidence on the prevalence and patterns of global antimicrobial use in the treatment of COVID-19 patients; identifies the most commonly used antibiotics and clinical scenarios associated with antibiotic prescribing in the first phase of the pandemic; and explores the impact of documented antibiotic prescribing on treatment outcomes in COVID-19 patients. The review complies with PRISMA guidelines for Scoping Reviews and the protocol is registered with the Open Science Framework. In the first six months of the pandemic, there was a similar mean antibiotic prescribing rate between patients with severe or critical illness (75.4%) and patients with mild or moderate illness (75.1%). The proportion of patients prescribed antibiotics without clinical justification was 51.5% vs. 41.9% for patients with mild or moderate illness and those with severe or critical illness. Comparison of patients who were provided antibiotics with a clinical justification with those who were given antibiotics without clinical justification showed lower mortality rates (9.5% vs. 13.1%), higher discharge rates (80.9% vs. 69.3%), and shorter length of hospital stay (9.3 days vs. 12.2 days). In the first 6 months of the pandemic, antibiotics were prescribed for COVID-19 patients regardless of severity of illness. A large proportion of antibiotic prescribing for mild and moderate COVID-19 patients did not have clinical evidence of a bacterial co-infection. Antibiotics may not be beneficial to COVID-19 patients without clinical evidence of a bacterial co-infection

Impacts of Antibiotic Residues in the Environment on Bacterial Resistance and Human Health in Eastern China: An Interdisciplinary Mixed-Methods Study Protocol

Antibiotic resistance is a global health challenge that threatens human and animal lives, especially among low-income and vulnerable populations in less-developed countries. Its multi-factorial nature requires integrated studies on antibiotics and resistant bacteria in humans, animals, and the environment. To achieve a comprehensive understanding of the situation and management of antibiotic use and environmental transmission, this paper describes a study protocol to document human exposure to antibiotics from major direct and indirect sources, and its potential health outcomes. Our mixed-methods approach addresses both microbiological and pathogen genomics, and epidemiological, geospatial, anthropological, and sociological aspects. Implemented in two rural residential areas in two provinces in Eastern China, linked sub-studies assess antibiotic exposure in population cohorts through household surveys, medicine diaries, and biological sampling; identify the types and frequencies of antibiotic resistance genes in humans and food-stock animals; quantify the presence of antibiotic residues and antibiotic resistance genes in the aquatic environment, including wastewater; investigate the drivers and behaviours associated with human and livestock antibiotic use; and analyse the national and local policy context, to propose strategies and systematic measurements for optimising and monitoring antibiotic use. As a multidisciplinary collaboration between institutions in the UK and China, this study will provide an in-depth understanding of the influencing factors and allow comprehensive awareness of the complexity of AMR and antibiotic use in rural Eastern China

Machine Learning and Swarm Optimization Algorithm in Temperature Compensation of Pressure Sensors

The main temperature compensation method for MEMS piezoresistive pressure sensors is software compensation, which processes the sensor data using various algorithms to improve the output accuracy. However, there are few algorithms designed for sensors with specific ranges, most of which ignore the operating characteristics of the sensors themselves. In this paper, we propose three temperature compensation methods based on swarm optimization algorithms fused with machine learning for three different ranges of sensors and explore the partitioning ratio of the calibration dataset on Sensor A. The results show that different algorithms are suitable for pressure sensors of different ranges. An optimal compensation effect was achieved on Sensor A when the splitting ratio was 33.3%, where the zero-drift coefficient was 2.88 × 10−7/°C and the sensitivity temperature coefficient was 4.52 × 10−6/°C. The algorithms were compared with other algorithms in the literature to verify their superiority. The optimal segmentation ratio obtained from the experimental investigation is consistent with the sensor operating temperature interval and exhibits a strong innovation

Numerical and experimental study on the impact between a free falling wedge and water

In this paper, numerical and experimental studies are performed to investigate the liquid impact on a free falling wedge. In the numerical simulation, the structure is assumed to be rigid and the elastic response is ignored. The fully nonlinear coupling between wedge and water is considered by an auxiliary function method based on the Boundary Element Method (BEM). At the intersection of the wedge surface and liquid surface, two coincident nodes are used to decouple the boundary conditions. The Eulerian free surface conditions in the local coordinate system are adopted to update the deformed free surface. In the experiments, five pressure sensors are fixed on each side of the wedge which is released from an experimental installation. Steel and aluminum wedges that have different structural elasticity are used in the experiments to investigate the influence of structural elasticity on the impact force. Numerical results are compared with experimental data and they agree very well. The influence of fluid gravity, body mass, initial entry speed and deadrise angle on the impact pressure are further investigated. Keywords: Impact, Boundary element method, Fully nonlinear boundary conditions, Experimental stud

Water–Medium Organic Reactions Catalyzed by Active and Reusable Pd/Y Heterobimetal–Organic Framework

A Pd/Y heterobimetallic MOF (denoted as Pd/Y-MOF) catalyst is synthesized by coordination of Pd­(II) and Y­(III) with 2,2′-bipyridine-5,5′-dicarboxylate acid (bpydc) under microwave irradiation condition and is characterized by XRD Rietveld refinement, FTIR, Raman, TG-DTA, and XPS. It is shown that the 3D extended framework is constructed by linking Pd­(bpydc)­Cl₂ building blocks via Y­(III) coordinating to carboxylic groups. Pd/Y-MOF exhibits higher catalytic activity than Pd­(bpydc)­Cl₂ in Suzuki-Miyaura coupling reaction and Sonogashira reaction owing to the highly dispersed Pd­(II) sites in the layered structure of Pd/Y-MOF and the cooperative effect between Pd­(II) and Y­(III). The heterogeneity studies provide mechanistic evidence that the reaction proceeds on the surface of Pd­(II) ions in the crystal framework. Thus, Pd/Y-MOF exhibits impressive size selectivity toward substrates. With the small-sized reactants, it displays comparable activities with Pd­(OAc)₂ homogeneous catalyst. However, extremely poor activity in Suzuki-Miyaura coupling reaction with bulk substrates 1-iodonaphthalene and 4-(<i>tert</i>-butyl) iodobenzene is observed due to the inhibition of diffusion into the micropore channels. In addition, Pd/Y-MOF can be easily recycled and reused owing to the high stability of the framework formed by coordination of Y­(III) with carboxylic group. The incorporation of Pd­(II) into the crystal framework of Pd/Y-MOF prohibits the leaching of Pd­(II) active species

Water–Medium Organic Reactions Catalyzed by Active and Reusable Pd/Y Heterobimetal–Organic Framework

A Pd/Y heterobimetallic MOF (denoted as Pd/Y-MOF) catalyst is synthesized by coordination of Pd­(II) and Y­(III) with 2,2′-bipyridine-5,5′-dicarboxylate acid (bpydc) under microwave irradiation condition and is characterized by XRD Rietveld refinement, FTIR, Raman, TG-DTA, and XPS. It is shown that the 3D extended framework is constructed by linking Pd­(bpydc)­Cl₂ building blocks via Y­(III) coordinating to carboxylic groups. Pd/Y-MOF exhibits higher catalytic activity than Pd­(bpydc)­Cl₂ in Suzuki-Miyaura coupling reaction and Sonogashira reaction owing to the highly dispersed Pd­(II) sites in the layered structure of Pd/Y-MOF and the cooperative effect between Pd­(II) and Y­(III). The heterogeneity studies provide mechanistic evidence that the reaction proceeds on the surface of Pd­(II) ions in the crystal framework. Thus, Pd/Y-MOF exhibits impressive size selectivity toward substrates. With the small-sized reactants, it displays comparable activities with Pd­(OAc)₂ homogeneous catalyst. However, extremely poor activity in Suzuki-Miyaura coupling reaction with bulk substrates 1-iodonaphthalene and 4-(<i>tert</i>-butyl) iodobenzene is observed due to the inhibition of diffusion into the micropore channels. In addition, Pd/Y-MOF can be easily recycled and reused owing to the high stability of the framework formed by coordination of Y­(III) with carboxylic group. The incorporation of Pd­(II) into the crystal framework of Pd/Y-MOF prohibits the leaching of Pd­(II) active species

Research on the influence of production fluctuation of high-production gas well on service security of tubing string

The production of high temperature and high pressure gas wells fluctuates with time, which makes the pressure in the string fluctuate obviously and affects the service security of tubing string. In this paper, a pressure fluctuation model of the complete production process (including well opening, production and shut-in) is established, which is suitable for the multiphase flow of gas well. The pressure fluctuation in the tubing string is simulated. Influence of different well depth and average production on the fluctuating pressure of gas well are analyzed. According to the research results, if the well opening time top is 50 s, a transient pressure fluctuation is generated at wellhead and drops gradually. After the production starts, a pressure fluctuation will occur at wellhead 10~15 s after top, which is small and attenuates quickly. Pressure increases quickly in the shut-in moment and reaches the peak at tsh. Although pressure increases gradually with the well depth, fluctuation flattens out. The hysteresis phenomenon in appearance of pressure wave becomes more and more obvious with the well depth. The greater the production of gas well, the greater the pressure fluctuation in tubing string during well opening and production, but the value may not be very high. During well shut-in, the greater the production, the greater the pressure fluctuation and the value. Amplitude, angular frequency and value of phase are in direct proportion to pressure fluctuation degree and valve radix is in inverse proportion to pressure, which means that the greater the valve radix, the smaller the pressure

Methyl orange removal by combined visible-light photocatalysis and membrane distillation

A photocatalytic membrane reactor combining a visible-light BiOBr photocatalyst and direct contact membrane distillation was studied for the removal of methyl orange from an aqueous solution. The hierarchical flower-like BiOBr microspheres, assemblies of BiOBr nanosheets, exhibited high efficiency for methyl orange photo-degradation under visible-light irradiation and due to their large specific surface area, their visible-light absorbance and the lower recombination of photo-generated electrons and holes. The main active species during the photo-degradation process was determined to be O-2 radicals. The organic pollutant and catalyst were retained on the feed side, as themembrane distillation only allowedwater vapor to permeate through the hydrophobic membrane, leading to a high quality water stream on the permeate side. The micrometer size of the BiOBr photocatalyst may prevent fouling of the polytetrafluoroethylene membrane, making the photocatalytic membrane reactor applicable for industrial wastewater treatment