46 research outputs found
Characterizing Dust-Radiation Feedback and Refining the Horizontal Resolution of the MarsWRF Model Down to 0.5 Degree
Acknowledgments Once again, our warmest thanks go to the PlanetWRF development team for providing the MarsWRF model free of charge to us and their proactive attitude in general. We would also like to thank two anonymous reviewers and the Associate Editor Dr Claire Newman for their several detailed and insightful comments and suggestions that helped to significantly improve the quality of the paper. We would like to acknowl- edge the support of this work by funding from the United Arab Emirates University (UAE University). Also, we are deeply grateful to High-Performance Computing, Division of Information Technology, UAE University, for the valuable access to the computational resources required for this work. We thank IT engineers Asma AlNeyadi, Anil Thomas, and Nithin Damodaran for their professional assistance and support in technical questions. M.-P. Z. has been partially funded by the AEI (MDM-2017-0737, Unity of Excellence âMarĂa de Maeztuâ - Centro de Astro- biologĂa (CSIC-INTA)) and the Spanish Ministry of Science and Innovation (PID2019-104205GB-C219). Finally, we declare that there are no real or perceived conflicts of interests for any author.Peer reviewedPublisher PD
Fully Interactive and Refined Resolution Simulations of the Martian Dust Cycle by the MarsWRF Model
Acknowledgments: First of all, our warmest thanks go to the PlanetWRF development team for providing the MarsWRF model free of charge to us and their proactive attitude in general. We thank Andy Heaps, National Centre for Atmospheric Science (NCAS), Department of Meteorology, University of Reading, UK, for his helpful advice regarding the data visualization using cfâPython. We would also like to thank Michael Mischna, Alexandre Kling, and the Associate Editor Claire Newman for their several detailed and insightful comments and suggestions that helped to significantly improve the quality of the paper. M. P. Z. acknowledges the partial support by the Spanish State Research Agency (AEI) project MDMâ2017â0737 Centro de AstrobiologĂa (CSICâINTA), Unidad de Excelencia MarĂa de Maeztu. Internally, we would like to express our greatest thanks to the HighâPerformance Computing, Division of Information Technology, United Arab Emirates University. Our particular thanks go to Asma AlNeyadi, Anil Thomas, and Nithin Damodaran for their intensive and continuous support in technically demanding questions. Also, we would like to thank the Digitization Unit, UAEU Libraries, for the digitization of auxiliary data on the observational record of the atmospheric T15 temperature and vertical weighting functions of Viking/IRTM. In addition, we thank UAEU Libraries for their assistance in making supporting data of this article available online. In particular, we are grateful to Digitization Technician Shireen M. Wolied, Fadl M. Musa/Digital Library Service, and Student Muhammad Abdul Rahim Sami Ullah. Funding Information: United Arab Emirates University (UAEU). Grant Number: 21R033âNSS Center 7â2017 Spanish State Research Agency (AEI). Grant Number: MDMâ2017â0737Peer reviewedPublisher PD
Bottom ash utilization: a review on engineering applications and environmental aspects
Bottom ash produced from coal-fired power plants has been utilized in engineering applications for the purpose of recycling and solving disposal issue of bottom ash. This study reviews various applications of bottom ash in engineering fields. The engineering properties exhibited by bottom ash in terms of free draining, granular, lightweight and interlocking nanostructures allow them to be used for different functions. The bottom ash used is not limited to its raw state, but can be mixed and modified for advanced applications without neglecting the impacts on the environmental. The presence of metals in bottom ash are well known and being discussed whether they are harmful to the environment. Many countries have their own threshold limit of maximum contaminants, hence TCLP result will determine the hazardous status of bottom ash. This review helps in promoting the solution and potential usage of bottom ash, since coal is one of the dominant source of energy in power generation sector
Evaluation of coal bottom ash properties and its applicability as engineering material
Coal ash is obtained in the combustion of coal for electricity production in coal based power stations. The non-combustible by-product including bottom ash and fly ash are discarded as a landfill. Consequently, the hazardous elements contained in the ashes can adulterate the ground and surface water. This study was carried out to emphasize the engineering properties of bottom ash collected at Tanjung Bin power station. An experimental study was carried out for particle size analysis, specific gravity, shear strength, compaction and relative density. The results depict that bottom ash possess particle size distribution nearly identical to sand, low specific gravity and dry density as compared to natural soil and having higher internal friction angle closer to granular materials. Based on the results, bottom ash can be employed in roadways, embankments and filling material for retaining walls by virtue of its low specific gravity, easy to compact and good frictional characteristics
In vitro antimicrobial activity and characterization of mangrove isolates of streptomycetes effective against bacteria and fungi of nosocomial origin
The complex X-ray spectrum of NGC 4507
XMM-Newton and Chandra/HETG spectra of the Compton-thin (NH 4x10^{23}
cm^{-2}) Seyfert 2 galaxy, NGC 4507, are analyzed and discussed. The main
results are: a) the soft X-ray emission is rich in emission lines; an (at
least) two--zone photoionization region is required to explain the large range
of ionization states. b) The 6.4 keV iron line is likely emitted from
Compton-thick matter, implying the presence of two circumnuclear cold regions,
one Compton-thick (the emitter), one Compton-thin (the cold absorber). c)
Evidence of an Fe xxv absorption line is found in the Chandra/HETG spectrum.
The column density of the ionized absorber is estimated to be a few x10^{22}
cm^{-2}.Comment: accepted for publication in A&
Correction to: Two years later: Is the SARS-CoV-2 pandemic still having an impact on emergency surgery? An international cross-sectional survey among WSES members
Background: The SARS-CoV-2 pandemic is still ongoing and a major challenge for health care services worldwide. In the first WSES COVID-19 emergency surgery survey, a strong negative impact on emergency surgery (ES) had been described already early in the pandemic situation. However, the knowledge is limited about current effects of the pandemic on patient flow through emergency rooms, daily routine and decision making in ES as well as their changes over time during the last two pandemic years. This second WSES COVID-19 emergency surgery survey investigates the impact of the SARS-CoV-2 pandemic on ES during the course of the pandemic.
Methods: A web survey had been distributed to medical specialists in ES during a four-week period from January 2022, investigating the impact of the pandemic on patients and septic diseases both requiring ES, structural problems due to the pandemic and time-to-intervention in ES routine.
Results: 367 collaborators from 59 countries responded to the survey. The majority indicated that the pandemic still significantly impacts on treatment and outcome of surgical emergency patients (83.1% and 78.5%, respectively). As reasons, the collaborators reported decreased case load in ES (44.7%), but patients presenting with more prolonged and severe diseases, especially concerning perforated appendicitis (62.1%) and diverticulitis (57.5%). Otherwise, approximately 50% of the participants still observe a delay in time-to-intervention in ES compared with the situation before the pandemic. Relevant causes leading to enlarged time-to-intervention in ES during the pandemic are persistent problems with in-hospital logistics, lacks in medical staff as well as operating room and intensive care capacities during the pandemic. This leads not only to the need for triage or transferring of ES patients to other hospitals, reported by 64.0% and 48.8% of the collaborators, respectively, but also to paradigm shifts in treatment modalities to non-operative approaches reported by 67.3% of the participants, especially in uncomplicated appendicitis, cholecystitis and multiple-recurrent diverticulitis.
Conclusions: The SARS-CoV-2 pandemic still significantly impacts on care and outcome of patients in ES. Well-known problems with in-hospital logistics are not sufficiently resolved by now; however, medical staff shortages and reduced capacities have been dramatically aggravated over last two pandemic years
Immunogenicity of standard and extended dosing intervals of BNT162b2 mRNA vaccine
Extension of the interval between vaccine doses for the BNT162b2 mRNA vaccine was introduced in the United Kingdom to accelerate population coverage with a single dose. At this time, trial data were lacking, and we addressed this in a study of United Kingdom healthcare workers. The first vaccine dose induced protection from infection from the circulating alpha (B.1.1.7) variant over several weeks. In a substudy of 589 individuals, we show that this single dose induces severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) neutralizing antibody (NAb) responses and a sustained B and T cell response to the spike protein. NAb levels were higher after the extended dosing interval (6â14 weeks) compared with the conventional 3- to 4-week regimen, accompanied by enrichment of CD4+ T cells expressing interleukin-2 (IL-2). Prior SARS-CoV-2 infection amplified and accelerated the response. These data on dynamic cellular and humoral responses indicate that extension of the dosing interval is an effective immunogenic protocol
T-cell and antibody responses to first BNT162b2 vaccine dose in previously infected and SARS-CoV-2-naive UK health-care workers: a multicentre prospective cohort study
Background
Previous infection with SARS-CoV-2 affects the immune response to the first dose of the SARS-CoV-2 vaccine. We aimed to compare SARS-CoV-2-specific T-cell and antibody responses in health-care workers with and without previous SARS-CoV-2 infection following a single dose of the BNT162b2 (tozinameran; PfizerâBioNTech) mRNA vaccine.
Methods
We sampled health-care workers enrolled in the PITCH study across four hospital sites in the UK (Oxford, Liverpool, Newcastle, and Sheffield). All health-care workers aged 18 years or older consenting to participate in this prospective cohort study were included, with no exclusion criteria applied. Blood samples were collected where possible before vaccination and 28 (±7) days following one or two doses (given 3â4 weeks apart) of the BNT162b2 vaccine. Previous infection was determined by a documented SARS-CoV-2-positive RT-PCR result or the presence of positive anti-SARS-CoV-2 nucleocapsid antibodies. We measured spike-specific IgG antibodies and quantified T-cell responses by interferon-Îł enzyme-linked immunospot assay in all participants where samples were available at the time of analysis, comparing SARS-CoV-2-naive individuals to those with previous infection.
Findings
Between Dec 9, 2020, and Feb 9, 2021, 119 SARS-CoV-2-naive and 145 previously infected health-care workers received one dose, and 25 SARS-CoV-2-naive health-care workers received two doses, of the BNT162b2 vaccine. In previously infected health-care workers, the median time from previous infection to vaccination was 268 days (IQR 232â285). At 28 days (IQR 27â33) after a single dose, the spike-specific T-cell response measured in fresh peripheral blood mononuclear cells (PBMCs) was higher in previously infected (n=76) than in infection-naive (n=45) health-care workers (median 284 [IQR 150â461] vs 55 [IQR 24â132] spot-forming units [SFUs] per 106 PBMCs; p<0·0001). With cryopreserved PBMCs, the T-cell response in previously infected individuals (n=52) after one vaccine dose was equivalent to that of infection-naive individuals (n=19) after receiving two vaccine doses (median 152 [IQR 119â275] vs 162 [104â258] SFUs/106 PBMCs; p=1·00). Anti-spike IgG antibody responses following a single dose in 142 previously infected health-care workers (median 270â373 [IQR 203â461â535â188] antibody units [AU] per mL) were higher than in 111 infection-naive health-care workers following one dose (35â001 [17â099â55â341] AU/mL; p<0·0001) and higher than in 25 infection-naive individuals given two doses (180â904 [108â221â242â467] AU/mL; p<0·0001).
Interpretation
A single dose of the BNT162b2 vaccine is likely to provide greater protection against SARS-CoV-2 infection in individuals with previous SARS-CoV-2 infection, than in SARS-CoV-2-naive individuals, including against variants of concern. Future studies should determine the additional benefit of a second dose on the magnitude and durability of immune responses in individuals vaccinated following infection, alongside evaluation of the impact of extending the interval between vaccine doses.
Funding
UK Department of Health and Social Care, and UK Coronavirus Immunology Consortium
Two doses of SARS-CoV-2 vaccination induce robust immune responses to emerging SARS-CoV-2 variants of concern
The extent to which immune responses to natural infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and immunization with vaccines protect against variants of concern (VOC) is of increasing importance. Accordingly, here we analyse antibodies and T cells of a recently vaccinated, UK cohort, alongside those recovering from natural infection in early 2020. We show that neutralization of the VOC compared to a reference isolate of the original circulating lineage, B, is reduced: more profoundly against B.1.351 than for B.1.1.7, and in responses to infection or a single dose of vaccine than to a second dose of vaccine. Importantly, high magnitude T cell responses are generated after two vaccine doses, with the majority of the T cell response directed against epitopes that are conserved between the prototype isolate B and the VOC. Vaccination is required to generate high potency immune responses to protect against these and other emergent variants