The development of a quantitative model that correlates conduction in and sensing with
p
-type gas sensitive metal oxides is presented here. The theoretical results are confronted with the ...experimental data and found to be in very good agreement. The model also explains the differences between the performance of gas sensors based on
n
and
p
-type metal oxides and indicates the possible improvement routes.
A model for the detection of CO in the presence of humidity is proposed for thick porous film gas sensors based on p-type CuO. The sensing mechanism is investigated by means of simultaneous DC ...electrical resistance and work function changes measurements combined with appropriate modeling of the conduction in the polycrystalline sensing film. The experiments were performed at 150
°C in dry and humid air backgrounds. The conclusion is that, very similarly to the case of undoped SnO
2, the explanation of the cross-interference of water in the CO detection is the fact that both react with pre-adsorbed oxygen ions.
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•Non-apatite inorganic P (including microbial polyphosphate) is released at pH 6.•pH of 4 rather than 6 is needed to release more apatite inorganic P from WAS.•Organic P is the most ...difficult fraction to release from WAS.•P fractionation analysis aids in evaluating potential for P recovery from WAS.
Waste activated sludge (WAS) can become an important source of phosphorus (P). P speciation was examined under anaerobic conditions, with different pH (4, 6 and 8) and temperatures (10, 20 and 35 °C). Aqueous P was measured and an extraction protocol was used to find three solid phosphorus fractions. A pH of 4 and a temperature of 35 °C gave a maximum of 51% of total P solubilized in 22 days with 50% of total P solubilized in 7 days. Batch tests indicate that little pH depression is needed to release non-apatite inorganic P (including microbial polyphosphate), while a pH of 4 rather than 6 will release more apatite inorganic P, and that organic P is relatively more difficult to release from WAS. Fractionation analysis of P in WAS can aid in design of more efficient methods for P recovery from WAS.
Summary
Maintaining safe elective surgical activity during the global coronavirus disease 2019 (COVID‐19) pandemic is challenging and it is not clear how COVID‐19 may impact peri‐operative morbidity ...and mortality in this population. Therefore, adaptations to normal care pathways are required. Here, we establish if implementation of a bespoke peri‐operative care bundle for urgent elective surgery during a pandemic surge period can deliver a low COVID‐19‐associated complication profile. We present a single‐centre retrospective cohort study from a tertiary care hospital of patients planned for urgent elective surgery during the initial COVID‐19 surge in the UK between 29 March and 12 June 2020. Patients asymptomatic for COVID‐19 were screened by oronasal swab and chest imaging (chest X‐ray or computed tomography if aged ≥ 18 years), proceeding to surgery if negative. COVID‐19 positive patients at screening were delayed. Postoperatively, patients transitioning to COVID‐19 positive status by reverse transcriptase polymerase chain reaction testing were identified by an in‐house tracking system and monitored for complications and death within 30 days of surgery. Out of 557 patients referred for surgery (230 (41.3%) women; median (IQR range) age 61 (48–72 1–89)), 535 patients (96%) had COVID‐19 screening, of which 13 were positive (2.4%, 95%CI 1.4–4.1%). Out of 512 patients subsequently undergoing surgery, 7 (1.4%) developed COVID‐19 positive status (1.4%, 95%CI 0.7–2.8%) with one COVID‐19‐related death (0.2%, 95%CI 0.0–1.1%) within 30 days. Out of these seven patients, four developed pneumonia, of which two required invasive ventilation including one patient with acute respiratory distress syndrome. Low rates of COVID‐19 infection and mortality in the elective surgical population can be achieved within a targeted care bundle. This should provide reassurance that elective surgery can continue, where possible, despite high community rates of COVID‐19.
Studies suggest that increased breastfeeding rates can provide substantial financial savings, but the scale of such savings in the UK is not known.
To calculate potential cost savings attributable to ...increases in breastfeeding rates from the National Health Service perspective.
Cost savings focussed on where evidence of health benefit is strongest: reductions in gastrointestinal and lower respiratory tract infections, acute otitis media in infants, necrotising enterocolitis in preterm babies and breast cancer (BC) in women. Savings were estimated using a seven-step framework in which an incidence-based disease model determined the number of cases that could have been avoided if breastfeeding rates were increased. Point estimates of cost savings were subject to a deterministic sensitivity analysis.
Treating the four acute diseases in children costs the UK at least £89 million annually. The 2009-2010 value of lifetime costs of treating maternal BC is estimated at £959 million. Supporting mothers who are exclusively breast feeding at 1 week to continue breast feeding until 4 months can be expected to reduce the incidence of three childhood infectious diseases and save at least £11 million annually. Doubling the proportion of mothers currently breast feeding for 7-18 months in their lifetime is likely to reduce the incidence of maternal BC and save at least £31 million at 2009-2010 value.
The economic impact of low breastfeeding rates is substantial. Investing in services that support women who want to breast feed for longer is potentially cost saving.
The southward penetration of mid-latitude westerlies and their interaction with monsoon current are harbinger of intense rainfall activity over northern and central India. Such synoptic condition ...prevailed during June 14–17, 2013, and unleashed relentless rainfall over the state of Uttarakhand. Observational aspects of this event have been explored using surface, satellite and reanalysis data. Precipitation features have been explored using data from Precipitation Radar Onboard TRMM satellite in conjunction with TRMM-TB42, Automatic Weather Station and Automatic Rain Gauge Station data. The ERA interim dataset has been used to explore prevalent synoptic conditions, and Modern-Era Retrospective Analysis for Research and Applications reanalysis fields revealed that prevalent synoptic features led to moisture flux convergence in lower troposphere. Vertically integrated water vapor transport over the India and adjoining oceanic region is evaluated to gain an insight into the dynamical mechanism of rainfall activity over Uttarakhand. Results reveal that interplay between movement of monsoon low along the monsoon trough resulting in strong low-level convergence and constant feeding of moisture from Arabian Sea and Bay of Bengal and strong upper-level divergence owing to southward intrusion of mid-latitude westerly trough resulted in heavy rainfall activity over Uttarakhand.
Abstract
Electromagnetic wave scattering and scintillation can occur at high latitudes of the Earth when polar cap patches are present. Polar cap patches range in size from 100 to 1,000 km and have ...densities on the order of 2–10 times that of the background ionosphere. Within polar cap patches, plasma irregularities caused by gradient drift instabilities are observed throughout the patch as elongated slivers. These irregularities vary in size from centimeters to tens of kilometers. Three major challenges must be overcome to thoroughly study high‐frequency electromagnetic wave interactions with polar cap patches: (1) the complex geometrical features of the irregularities within the patches must be accommodated; (2) the non‐approximated Maxwell's equations should be solved to account for all the physics of electromagnetic wave propagation, scattering, diffraction, etc.; and (3) the physics of electromagnetic wave interactions with magnetized ionospheric plasma must be included. In this paper, the finite‐difference time‐domain (FDTD) method is used to overcome the above three challenges and solve for electromagnetic wave interactions with plasma irregularities within a polar cap patch. Irregularities and patch profiles are generated using Defense Meteorological Satellite Program data and incorporated into the FDTD model. The transmission coefficients for high‐frequency electromagnetic wave propagation through perturbed and unperturbed ionospheres, as well as for magnetized and unmagnetized ionospheric plasma ionospheres are calculated. From these simulations, the effects of small‐scale irregularities on high‐frequency propagation are observed.
Key Points
Maxwell's equations are solved to model electromagnetic wave propagation through ionospheric plasma irregularities of polar cap patches
Cumulative distribution function polar cap patch profiles are generated using defense meteorological satellite program data
Transmission coefficients are calculated for various unperturbed/perturbed and unmagnetized/magnetized ionospheric conditions
ABSTRACT
Role of the cloud parameterization scheme and critical relative humidity (RHcrit) for large‐scale precipitation is examined for simulating Indian summer monsoon (ISM) by the National Centers ...for Environmental Prediction (NCEP) climate forecast system version 2 (CFSv2). The major biases of the model simulations namely dry bias over the major continents, cold tropospheric temperature (TT) bias and cold sea surface temperature (SST) bias are related to biases in distribution of clouds. This study evaluates the role of variable RHcrit to get better simulation of high level clouds and reduce TT bias and cloud microphysical parameterization to improve the meridional gradient of TT towards achieving better simulation of south Asian monsoon precipitation. Sensitivity experiments of CFSv2 with the modified RHcrit and cloud microphysical scheme compared to the control simulation show that while the RHcrit leads to some development of the cloud distribution and contributes to some progress of the dry bias over India, the cloud microphysics changes lead to a significant improvement of the cloud simulations. Particularly, revised cloud microphysics scheme coupled with modified RHcrit results in a much improved global distribution of cloud fraction with zonal mean cloud fraction being close to observation. This leads to significant improvement in the meridional gradient of TT leading to rainfall over south Asian monsoon region. The dry bias is not only reduced over the Indian subcontinent but also over other regions of global tropics such as the central Africa and the northern South America. The annual cycle of all India rainfall is in good agreement with observation not only in amount but also in the onset and withdrawal phases. Thus, modifications in the cloud microphysical parameterization scheme in CFSv2 have played a vital role in simulation of the ISM in particular. The sensitivity experiments demonstrate the betterment of the mean monsoon and may lead to help improve monsoon forecasts.
The present study was intended to develop a Water Quality Index (WQI) for the coastal water of Visakhapatnam, India from multiple measured water quality parameters using different multivariate ...statistical techniques. Cluster analysis was used to classify the data set into three major groups based on similar water quality characteristics. Discriminant analysis was used to generate a discriminant function for developing a WQI. Discriminant analysis gave the best result for analyzing the seasonal variation of water quality. It helped in data reduction and found the most discriminant parameters responsible for seasonal variation of water quality. Coastal water was classified into good, average, and poor quality considering WQI and the nutrient load. The predictive capacity of WQI was proved with random samples taken from coastal areas. High concentration of ammonia in surface water during winter was attributed to nitrogen fixation by the phytoplankton bloom which resulted due to East India Coastal Current. This study brings out the fact that water quality in the coastal region not only depends on the discharge from different pollution sources but also on the presence of different current patterns. It also illustrates the usefulness of WQI for analyzing the complex nutrient data for assessing the coastal water and identifying different pollution sources, considering reasons for seasonal variation of water quality.
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