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Long-term outcomes after using retrievable vena cava filters in major trauma patients with contraindications to prophylactic anticoagulation
Get PDFPurpose
To investigate the long-term outcomes of using vena cava filters to prevent symptomatic pulmonary embolism (PE) in major trauma patients who have contraindications to prophylactic anticoagulation.
Methods
This was an a priori sub-study of a randomized controlled trial (RCT) involving long-term outcome data of 223 patients who were enrolled in Western Australia. State-wide clinical information system, radiology database and death registry were used to assess long-term outcomes, including incidences of venous thromboembolism, venous injury and mortality beyond day-90 follow-up.
Results
The median follow-up time of 198 patients (89%) who survived beyond 90 days was 65 months (interquartile range 59–73). Ten patients (5.1%) died after day-90 follow-up; and four patients developed venous thromboembolism, including two with symptomatic PE, all allocated to the control group (0 vs 4%, p = 0.043). Inferior vena cava injuries were not recorded in any patients. The mean total hospitalization cost, including the costs of the filter and its insertion and removal, to prevent one short- or long-term symptomatic PE was A1,205 or €820) were, however, substantially lower when the filter was used only for patients who could not be anticoagulated within seven days of injury.
Conclusion
Long-term complications related to retrievable filters were rare, and the cost of using filters to prevent symptomatic PE was acceptable when restricted to those who could not be anticoagulated within seven days of severe injury
Energy-efficient electrochemically-driven CO2 capture systems for biogas upgrading
Get PDFBiogas encompassing mainly CO2/CH4 mixture has gained increased attention as a renewable energy source over the last years, mainly due to its contributions to greenhouse gas (GHG) abatement. However, this gaseous stream has been undervalued owing to its high CO2 content. Capturing endogenous CO2 from biogas broadens its utilisation as a substitute for natural gas. High energy consumption of traditional CO2 capture technologies has led to an opportunity to develop an alternative technique for large-scale carbon capture. Employing an anion exchange membrane (AEM)-based electrochemical cell for CO2 removal from gas mixtures is a new strategy based on the pH-gradient generated during redox reactions. This technology offers significant practical advantages owing to near-ambient temperature and pressure operating conditions. To open avenues for development research on the electrochemically-driven CO2 capture technique, key principles and features of all major methods for CO2 capture in the literature were summarised as part of this thesis. While to date the (AEM)-based electrochemical cells have received eminent fame for their application in CO2 capture, there are still major enhancement researches required to enhance the technology maturity and reduce costs. In this thesis, the aim was to determine the viability of this CO2 capture system as an alternative to conventional technologies for biogas upgrading. In this context, the main research chapters are summarised as follows:
Firstly, a CO2 absorption column was integrated with an alkaline water electrolyser for biogas upgrading. After scrubbing CO2 in an aqueous absorption column, the resulting bicarbonate solution was fed through the cathode of an anion exchange membrane (AEM)-based electrolyser. With bicarbonate being the dominant anion, it migrates proportionally to the electron flow to the anode from where it is released together with anodic oxygen (O2). The proposed system allows electrochemically-assisted scrubbing and stripping of CO2 without the addition of chemicals. Coulombic efficiency calculations showed that the theoretical electron/carbon ratio of 1 (1 e/ 1 HCO3-) can be achieved by using a pH of 9 while using a traditional pH of around 13 results in more electrons and hence more energy requirement for electrochemical CO2 removal. As predicted from electrochemical stoichiometry, the system optimisation demonstrated that operating the integrated system at pH=9 results in the lowest energy requirement, even though the CO2 absorption rate in the absorbent pH= 13 was about three times higher than that at pH= 9. Results of this study suggest that integrated (AEM)-based alkaline water electrolyser and CO2 absorption column offer a low energy approach for the capture and removal of CO2 from biogas (0.25 to 0.92 kWh/kg CO2). This could potentially reduce the energy demand for CO2 separation from biogas by about 50% compared to the most energy-efficient technologies that are currently available.
Recovery of absorbed CO2 on the anode side of the alkaline membrane diminishes the O2 content in the anodic gas stream. Given this high purity electrolytic O2 has a growing industrial interest in diverse applications such as biological wastewater treatment processes we designed and developed an innovative three-chamber electrochemical cell configuration capable of capturing CO2 and recovering it in an intermediate chamber enabling concomitant anodic high-purity oxygen generation. Our prototype successfully demonstrated that CO2 recovery can be separated from the anodic O2 gas stream by adding a cation exchange membrane (CEM) to the cell. A concise model was also developed to accurately predict the polarisation characteristic of the designed electrochemical cell by considering the numerical coefficient for the Tafel equation and ohmic losses.
Next to the regeneration of spent alkaline solution for CO2 removal from biogas using an alkaline water electrolyser, the generated high-purity electrolytic O2 from the three-chamber electrochemical cell can be used as a valuable by-product in various industrial processes to improve the energy efficiency of the system. Our strategy to cut down the cost of electrochemically-driven CO2 removal was the effective utilisation of high-purity O2 in the aeration process of a wastewater treatment plant. The high-purity electrolytic O2 can be used to substitute the air in the conventional activated sludge process. To determine the benefit of switching from air to oxygen-enriched air or pure oxygen, an analytical model was derived to simulate the dynamic behaviour of a single bubble rising in stagnant water. This study explored the influence of operation parameters such as bubble diameter, and bubble release depth on gas-liquid mass transfer. The predicted results suggested that replacing air with high-purity oxygen in the aeration process of the conventional activated sludge can offset up to 30% of the energy required for water electrolysis. A greater advantage could be obtained by using the generated high-purity oxygen in the aeration system of industries with higher dissolved oxygen requirements such as the aquaculture industry.
Finally, co-mixing electrolytic H2 generated during electrochemical biogas upgrading and CH4 may not be desirable and present some challenges such as the increased probability of ignition and material degradability. In this scenario, electrolytic H2 could be recycled from the cathode to the anode side to replace the kinetically sluggish oxygen evolution reaction (OER). The technical and economic aspect of the H2 recycling cell to generate the pH gradient required for capturing and stripping CO2 was explored. The experimental results showed that the H2 recycling cell enables CO2 capture with a minimum electrochemical work of 0.19 kWh/kg CO2, which is 30% lower than the alkaline water electrolyser system where anodic OER limits the energy efficiency of the process.
The main conclusion drawn from this study is that the electrochemical-driven CO2 capture systems have the potential to reduce energy costs associated with the regeneration of spent alkaline absorbents in biogas upgrading systems
Exogenously applied salicylic acid boosts Morpho-Physiological traits, yield, and water productivity of lowland rice under normal and deficit irrigation
Get PDFThe main constraint on rice cultivation in the Mediterranean area is the limited irrigation and its large water consumption. In addition, rice is very sensitive to drought conditions because of drought stress on morpho-physiological traits and yield reduction. The application of salicylic acid (SA) has been noticed to be very effective in alleviating the adverse effects of drought stress on rice. The current investigation was conducted as a split-split arrangement under a randomized complete block design with two lowland rice cultivars (Giza177 and Giza179) and SA as a foliar application at four concentrations (0, 400, 700, and 1000 µM) under normal and drought conditions. The results showed that plant growth, leaf photosynthetic pigments, yields, and the most studied traits were significantly affected by irrigation (I), cultivar (C), and SA concentration (p ≤ 0.05 or 0.01). The interaction effect of I × C × SA was only significant on the carotenoids content (p ≤ 0.05). The reduction in grain yield and most studied traits was more pronounced under drought conditions. The Giza179 proved to be a drought-tolerant cultivar under all SA concentrations under drought conditions, while Giza177 was a drought-sensitive cultivar. The application of 700 µM SA gave the best grain yield in both rice cultivars under drought conditions compared to other SA concentrations. Grain yield for normal irrigation (Yp) and drought stress (Ys) conditions were highly positively correlated with indices of the mean productivity (MP), geometric mean productivity (GMP), stress tolerance index (STI), yield index (YI), yield stability index (YSI), drought resistance index (DI), harmonic mean (HM), and golden mean (GOL). While they are highly negatively correlated with the indices of the stress susceptibility index (SSI), tolerance index (TOL), yield reduction ratio (YR), stress susceptibility percentage index (SSPI), and abiotic tolerance index (ATI). It could be concluded that SA, as a growth regulator, could be used to alleviate the harmful effect of inadequate water availability in soil on rice cultivars as well as to improve the growth, water productivity, and grain yield
Reactivity to heparin in patients with alpha-gal allergy
No full textGalactose-alpha-1,3-galactose (alpha-gal) syndrome is an immunoglobulin (Ig)E-mediated allergy syndrome to an oligosaccharide found in nonprimate mammalian meat and mammalian-derived products. 1 Oral consumption reactions are characteristically delayed, but are immediate with parenteral administration. 1 Since the discovery of alpha-gal IgE antibodies while investigating hypersensitivity reactions to cetuximab, much attention has been paid to both theoretical risks and reported cases of hypersensitivity reactions to various medications and medical devices derived from nonprimate mammals. 1 ,2 The true extent of this risk is still largely unknown. 3 One medication of interest is heparin; both unfractionated heparin and low-molecular weight heparin, enoxaparin, are derived from porcine intestinal tissue. In a case of immediate hypersensitivity to heparin in a patient with a high concentration of alpha-gal–specific IgE (sIgE), we would like to draw attention to positive skin testing result to heparin products
Risk-Stratified Management to Remove Low-Risk Penicillin Allergy Labels in the Patients with COVID-19 in the Intensive Care Unit
No full textDelineating meta-quantitative trait loci for anthracnose resistance in common bean (Phaseolus vulgaris L.)
Get PDFAnthracnose, caused by the fungus Colletotrichum lindemuthianum, is one of the devastating disease affecting common bean production and productivity worldwide. Several quantitative trait loci (QTLs) for anthracnose resistance have been identified. In order to make use of these QTLs in common bean breeding programs, a detailed meta-QTL (MQTL) analysis has been conducted. For the MQTL analysis, 92 QTLs related to anthracnose disease reported in 18 different earlier studies involving 16 mapping populations were compiled and projected on to the consensus map. This meta-analysis led to the identification of 11 MQTLs (each involving QTLs from at least two different studies) on 06 bean chromosomes and 10 QTL hotspots each involving multiple QTLs from an individual study on 07 chromosomes. The confidence interval (CI) of the identified MQTLs was found 3.51 times lower than the CI of initial QTLs. Marker-trait associations (MTAs) reported in published genome-wide association studies (GWAS) were used to validate nine of the 11 identified MQTLs, with MQTL4.1 overlapping with as many as 40 MTAs. Functional annotation of the 11 MQTL regions revealed 1,251 genes including several R genes (such as those encoding for NBS-LRR domain-containing proteins, protein kinases, etc.) and other defense related genes. The MQTLs, QTL hotspots and the potential candidate genes identified during the present study will prove useful in common bean marker-assisted breeding programs and in basic studies involving fine mapping and cloning of genomic regions associated with anthracnose resistance in common beans
Artificial intelligence – Based video traffic policing for next generation networks
No full textThe constant increase in users’ bandwidth needs, through a large variety of multimedia applications, creates the need for highly effective network traffic control. This need is imperative in wireless networks, where the available bandwidth is limited, but is very important for wired networks as well. In this work we focus on the problem of policing video traffic from sources encoded with H.264 and H.265, given that these are the major state-of-the-art standards currently in the market. Building on work that has shown that classic traffic policing schemes can lead to unnecessarily strict policing for conforming video sources, we propose the use of Artificial Intelligence (AI) – based traffic policing schemes for video traffic. We conduct a performance evaluation of several AI – based schemes with the classic token bucket and we show that our proposed Frame Size Predictor and Policer scheme improve the performance of the classic token bucket by around 90% for conforming users, while providing only slightly worse policing results for non-conforming users
Evaluation of an ELISA for the diagnosis of bovine tuberculosis using milk samples from dairy cows in China
No full textBovine tuberculosis (bTB) is an important zoonotic disease in developing countries including China. Lack of rapid and simple detection methods for surveillance affects efficient control and eradication of this disease. The objective of this study was to determine the feasibility of using an individual and bulk milk sample ELISA based on the fusion protein of four specific antigens (CFP10/ESAT-6/MPB70/MPB83) of Mycobacterium bovis for the rapid detection and surveillance of bTB in dairy cattle herds and to identify individual animal factors that affect its results. The study population consisted of 388 dairy cows from four herds in Henan province, China. The serum sample ELISA (cut-off value 30%) and milk sample ELISA (cut-off value 10%) were shown to have good agreement, while, there was fair agreement between a blood sample IFN-γ in vitro release assay and the milk sample ELISA (cut-off value 10%) (Cohen’s kappa statistic of 0.492 and 0.306, respectively). The sensitivity and specificity for the milk sample ELISA using a S/P% cut-off value of 10%, as estimated using a Bayesian latent class analysis model, was 48.4% (95%CI: 31.0 – 85.2) and 97.1% (95%CI: 92.2 – 99.7), respectively. Although both ELISAs had comparable sensitivities and specificities, the milk sample ELISA had a greater discriminatory ability, as measured by the area under the curve (ROC), than the serum sample ELISA with the difference of their AUCs being − 0.069 (95%PCI: −0.121 to −0.021). Further, it was estimated that the lower limit of detection at an animal level lacto-prevalence might be 1.1% with this milk ELISA using bulk milk samples. Additionally, a mixed linear regression model, incorporating herd as a random effect variable, was constructed to investigate the association between natural log-transformed bTB sample-to-positive ratio (LnS/P%) and milk data. Across the model, natural log-transformed Somatic Cell Count (SCC) and parity had a positive effect on the LnS/P% of bTB antibody response, and milk urea nitrogen had a curvilinear association with LnS/P%. In conclusion, a milk ELISA for bTB antibodies, especially bulk tank milk antibodies, could be used as an efficient tool for rapid screening in surveillance, which might be followed by confirmatory testing with IFN-γ assay in dairy cattle, during the implementation of bTB control programmes. Relevant milk factors should be considered to adjust the S/P% with the aim of classifying the infection status of animals and herds as accurately as possible
HPC-PAA hydrogel smart windows with and without Cs0.32WO3: High solar modulation ability and luminous transmittance
No full textHydroxypropyl cellulose (HPC) hydrogel is a promising material for fabricating energy saving smart windows. However, its lower critical solution temperature (LCST = 42 oC) is much higher than comfortable room temperatures. In this work, we applied surface polymerization of acrylic acid (AA) monomers on HPC chains and synthesized HPC-polyacrylic acid (PAA) hydrogels with precisely controllable LCST in the range of 23.0–42.0 oC. The fabricated HPC-PAA hydrogel smart windows exhibited excellent Tlum, 22 °C of 91.8% and ΔTsol, 22–40 °C of 73.7%, outperforming VO2 hydrogel composites and photothermal nanoparticles doped hydrogel smart windows. Meanwhile, cesium tungsten bronze (Cs0.32WO3) photothermal nanoparticles can be introduced to the HPC-PAA hydrogel matrix, and the near infrared (NIR) shielding ability of Cs0.32WO3 allowed significant reduction of NIR transmittance of the smart windows from 81.7% to 41.6% at 22 oC, and from 19.3% to 3.6% at 40 oC. Temperature regulation tests in model houses revealed outstanding heat-shielding performance of Cs0.32WO3 (0.4 wt%)/HPC-PAA hydrogel smart windows, especially compared with ordinary double-glass windows. Furthermore, the HPC-PAA hydrogel and Cs0.32WO3 (0.4 wt%)/HPC-PAA hydrogel are non-toxic, biocompatible, low-cost, suggesting their suitability for energy-saving smart window applications