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1.
Atmospheric Chemistry and Physics ; 23(7):3905-3935, 2023.
Article in English | ProQuest Central | ID: covidwho-2276300

ABSTRACT

In orbit since late 2017, the Tropospheric Monitoring Instrument (TROPOMI) is offering new outstanding opportunities for better understanding the emission and fate of nitrogen dioxide (NO2) pollution in the troposphere. In this study, we provide a comprehensive analysis of the spatio-temporal variability of TROPOMI NO2 tropospheric columns (TrC-NO2) over the Iberian Peninsula during 2018–2021, considering the recently developed Product Algorithm Laboratory (PAL) product. We complement our analysis with estimates of NOx anthropogenic and natural soil emissions. Closely related to cloud cover, the data availability of TROPOMI observations ranges from 30 %–45 % during April and November to 70 %–80 % during summertime, with strong variations between northern and southern Spain. Strongest TrC-NO2 hotspots are located over Madrid and Barcelona, while TrC-NO2 enhancements are also observed along international maritime routes close the strait of Gibraltar, and to a lesser extent along specific major highways. TROPOMI TrC-NO2 appear reasonably well correlated with collocated surface NO2 mixing ratios, with correlations around 0.7–0.8 depending on the averaging time.We investigate the changes of weekly and monthly variability of TROPOMI TrC-NO2 depending on the urban cover fraction. Weekly profiles show a reduction of TrC-NO2 during the weekend ranging from -10 % to -40 % from least to most urbanized areas, in reasonable agreement with surface NO2. In the largest agglomerations like Madrid or Barcelona, this weekend effect peaks not in the city center but in specific suburban areas/cities, suggesting a larger relative contribution of commuting to total NOx anthropogenic emissions. The TROPOMI TrC-NO2 monthly variability also strongly varies with the level of urbanization, with monthly differences relative to annual mean ranging from -40 % in summer to +60 % in winter in the most urbanized areas, and from -10 % to +20 % in the least urbanized areas. When focusing on agricultural areas, TROPOMI observations depict an enhancement in June–July that could come from natural soil NO emissions. Some specific analysis of surface NO2 observations in Madrid show that the relatively sharp NO2 minimum used to occur in August (drop of road transport during holidays) has now evolved into a much broader minimum partly de-coupled from the observed local road traffic counting;this change started in 2018, thus before the COVID-19 outbreak. Over 2019–2021, a reasonable consistency of the inter-annual variability of NO2 is also found between both datasets.Our study illustrates the strong potential of TROPOMI TrC-NO2 observations for complementing the existing surface NO2 monitoring stations, especially in the poorly covered rural and maritime areas where NOx can play a key role, notably for the production of tropospheric O3.

2.
Flow ; 3, 2023.
Article in English | ProQuest Central | ID: covidwho-2263730

ABSTRACT

Natural ventilation can play an important role towards preventing the spread of airborne infections in indoor environments. However, quantifying natural ventilation flow rates is a challenging task due to significant variability in the boundary conditions that drive the flow. In the current study, we propose and validate an efficient strategy for using computational fluid dynamics to assess natural ventilation flow rates under variable conditions, considering the test case of a single-room home in a dense urban slum. The method characterizes the dimensionless ventilation rate as a function of the dimensionless ventilation Richardson number and the wind direction. First, the high-fidelity large-eddy simulation (LES) predictions are validated against full-scale ventilation rate measurements. Next, simulations with identical Richardson numbers, but varying dimensional wind speeds and temperatures, are compared to verify the proposed similarity relationship. Last, the functional form of the similarity relationship is determined based on 32 LES. Validation of the surrogate model against full-scale measurements demonstrates that the proposed strategy can efficiently inform accurate building-specific similarity relationships for natural ventilation flow rates in complex urban environments.

3.
The American Political Science Review ; 117(1):80-102, 2023.
Article in English | ProQuest Central | ID: covidwho-2230503

ABSTRACT

Survey data are commonly cited as evidence of widespread misperceptions and misinformed beliefs. This paper shows that surveys generally fail to identify the firm, deep, steadfast, confidently held beliefs described in leading accounts. Instead, even those who report 100% certain belief in falsehoods about well-studied topics like climate change, vaccine side effects, and the COVID-19 death toll exhibit substantial response instability over time. Similar levels of response stability are observed among those who report 100% certain belief in benign, politically uncontested falsehoods—for example, that electrons are larger than atoms and that lasers work by focusing sound waves. As opposed to firmly held misperceptions, claims to be highly certain of incorrect answers are best interpreted as "miseducated” guesses based on mistaken inferential reasoning. Those reporting middling and low levels of certainty are best viewed as making close-to-blind guesses. These findings recast existing evidence as to the prevalence, predictors, correction, and consequences of misperceptions and misinformed beliefs.

4.
Zagreb International Review of Economics & Business ; 25(2):165-181, 2022.
Article in English | ProQuest Central | ID: covidwho-2154573

ABSTRACT

We understand that atypical employment can be sustained if it provides benefits for both the employer and the employee, but these benefits, in most cases, have only an indirect effect on profit. This study examines whether workers with fixed-term employment could be more effective regarding certain performance indicators than their co-workers with indefinite employment contracts. Results show that in one of the two examined performance indicators (number of clients served), individuals working in an atypical form of employment are more efficient for almost all variables, while for the second performance indicator (value creation), they are not more efficient for either of the variables.

5.
Webology ; 19(1):2475-2490, 2022.
Article in English | ProQuest Central | ID: covidwho-1964724

ABSTRACT

Due to the on-going COVID-19 pandemic, industries are heavily reliant on online meeting platforms. The pandemic has forced most MNCs to rely on online platforms such as Zoom or Microsoft Teams to hold daily business meetings and even conferences and other corporate events. Schools and other educational institutions have also been forced to conduct classes and all other events through these platforms. This increased unavoidable dependence on online platforms has resulted in an exponential increase in advertising fraud. Advertising fraud is the application of any method or technology that hampers the proper delivery of advertisements to the proper audience or the proper place, or forcefully inserts advertisements at undesirable times or locations. This could take multiple forms and has become far more widespread with increased use of online platforms. Some common methods used for digital fraud can be the pay-per-click (PPC) model, domain spoofing or in the form of bots, but the main objective is to gain financial advantages from advertising transactions. The primary objective of this study is to identify and understand the factors lying behind the presence of fraudulent activities on any online medium and to analyse the probability of downloading an application after coming across the online advertisement, and watching it. The study also aims to highlight how marketing agencies tend to float fraud advertisement just to gain more revenue from their end.

6.
Remote Sensing ; 14(10):2342, 2022.
Article in English | ProQuest Central | ID: covidwho-1875741

ABSTRACT

The atmospheric molecular number density can be obtained from atmospheric temperature and pressure profiles and is a significant input parameter for the inversion of lidar measurements. When measurements of vertical profiles of temperature and pressure are not available, atmospheric models are typically considered a valid alternative option. This paper investigates the influence of different atmospheric models (forecast and reanalysis) on the retrieval of aerosol optical properties (extinction and backscatter coefficients) by applying Raman and elastic-only methods to lidar measurements, to assess their use in lidar data processing. In general, reanalyzes are more accurate than forecasts, but, typically, they are not delivered in time for allowing near-real-time lidar data analysis. However, near-real-time observation is crucial for real-time monitoring of the environment and meteorological studies. The forecast models used in the paper are provided by the Integrated Forecasting System operated by the European Centre for Medium-Range Weather Forecasts (IFS_ECMWF) and the Global Data Assimilation System (GDAS), whereas the reanalysis model is obtained from the fifth-generation European Centre for Medium-Range Weather Forecasts ReAnalysis v5 (N1 -https://media.proquest.com/media/hms/PFT/1/TPT6N?_a=ChgyMDIyMDUzMTEzNDEyNjI1NDo5NzgxMzQSBTg4MjU5GgpPTkVfU0VBUkNIIg4xNTguMTExLjIzNi4xOSoHMjAzMjMzODIKMjY3MDQxNTUxMjoNRG9jdW1lbnRJbWFnZUIBMFIGT25saW5lWgJGVGIDUEZUagoyMDIyLzAxLzAxcgoyMDIyLzEyLzMxegCCASlQLTEwMDc4NTItMjY3MjQtQ1VTVE9NRVItMTAwMDAyNTUtNTc2NDMxMZIBBk9ubGluZcoBc01vemlsbGEvNS4wIChXaW5kb3dzIE5UIDEwLjA7IFdpbjY0OyB4NjQpIEFwcGxlV2ViS2l0LzUzNy4zNiAoS0hUTUwsIGxpa2UgR2Vja28pIENocm9tZS8xMDIuMC41MDA1LjYxIFNhZmFyaS81MzcuMzbSARJTY2hvbGFybHkgSm91cm5hbHOaAgdQcmVQYWlkqgIrT1M6RU1TLU1lZGlhTGlua3NTZXJ2aWNlLWdldE1lZGlhVXJsRm9ySXRlbcoCD0FydGljbGV8RmVhdHVyZdICAVnyAgD6AgFZggMDV2ViigMcQ0lEOjIwMjIwNTMxMTM0MTI2MjU0OjM0MjIyOQ%3D%3D&_s=Os82DX%2BaBlhnLe1wnAEkKTgdQ4M%3D ERA5). The lidar dataset consists of measurements collected from four European Aerosol Research Lidar Network (EARLINET) stations during two intensive measurement campaigns and includes more than 200 cases at wavelengths of 355 nm, 532 nm, and 1064 nm. We present and discuss the results and influence of the forecast and reanalysis models in terms of deviations of the derived aerosol optical properties. The results show that the mean relative deviation in molecular number density is always below ±3%, while larger deviations are shown in the derived aerosol optical properties, and the size of the deviation depends on the retrieval method together with the different wavelengths. In general, the aerosol extinction coefficient retrieval is more dependent on the model used than the aerosol backscatter retrievals are. The larger influence on the extinction retrieval is mainly related to the deviation in the gradient of the temperature profile provided by forecast and reanalysis models rather than the absolute deviation of the molecular number density. We found that deviations in extinction were within ±5%, with a probability of 83% at 355 nm and 60% at 532 nm. Moreover, for aerosol backscatter coefficient retrievals, different models can have a larger impact when the backscatter coefficient is retrieved with the elastic method than when the backscatter coefficient is calculated using the Raman method at both 355 nm and 532 nm. In addition, the atmospheric aerosol load can also influence the deviations in the aerosol extinction and backscatter coefficients, showing a larger impact under low aerosol loading scenarios.

7.
View ; 3(3), 2022.
Article in English | ProQuest Central | ID: covidwho-1870940

ABSTRACT

Pharmaceutical drugs and vaccines require the use of material containers for protection, storage, and transportation. Glass and plastic materials are widely used for packaging, and a longstanding challenge in the field is the nonspecific adsorption of pharmaceutical drugs to container walls – the so‐called “sticky containers, vanishing drugs” problem – that effectively reduces the active drug concentration and can cause drug denaturation. This challenge has been frequently discussed in the case of the anticancer drug, paclitaxel, and the ongoing coronavirus disease 2019 (COVID‐19) pandemic has brought renewed attention to this material science challenge in light of the need to scale up COVID‐19 vaccine production and to secure sufficient quantities of packaging containers. To reduce nonspecific adsorption on inner container walls, various strategies based on siliconization and thin polymer films have been explored, while it would be advantageous to develop mass‐manufacturable, natural material solutions, especially ones involving pharmaceutical grade excipients. Inspired by how lipid nanoparticles have revolutionized the vaccine field, in this perspective, we discuss the prospects for developing lipid bilayer coatings to prevent nonspecific adsorption of pharmaceutical drugs and vaccines and how recent advances in lipid bilayer coating fabrication technologies are poised to accelerate progress in the field. We critically discuss recent examples of how lipid bilayer coatings can prevent nonspecific sticking of proteins and vaccines to relevant material surfaces and examine future translational prospects.

8.
Geoscience Communication ; 5(2):143-150, 2022.
Article in English | ProQuest Central | ID: covidwho-1863171

ABSTRACT

W.A.T.E.R. stands for Workshop on Advanced measurement Techniques and Experimental Research. It is an initiative started in 2016 in association with the Experimental Methods and Instrumentation (EMI) committee of the International Association for Hydro-Environment Engineering and Research (IAHR) aimed at advancing the use of experimental techniques in hydraulics and fluid mechanics research. It provides a structured approach for the learning and training workshop series to postgraduate students (aiming specifically at doctoral students), young researchers, and professionals with an experimental background in fluid mechanics. It offers an opportunity to learn about state-of-the-art instrumentation and measurement techniques and the latest developments in the field by partnering with manufacturers. W.A.T.E.R. brings together academics, instrumentation manufacturers and public sectors in a structured setting to share knowledge and to learn from good practices. It is about training people who already have a certain knowledge and skill level but who need to go deeper and/or wider in the field of measurement and experimental research.

9.
Sustainability ; 14(9):4928, 2022.
Article in English | ProQuest Central | ID: covidwho-1842961

ABSTRACT

Common problems when carrying out water footprint (WF) assessments are obtaining specific primary data, dealing with the complexity of its computation, and the availability of quality data. In a supply chain context, inconsistencies are even more exacerbated. In order to fill in this research gap, this study proposes and evaluates the content validity of a survey scale to assess WF management initiatives implemented by companies, with a focus on supply chains and the agriculture industry. In order to do so, a literature review was performed to identify candidate survey items whose content was later validated with experts in terms of their relevance, clarity, and essentiality to measure WF management. Content validity was assessed using several indices (items’ content validity index (I-CVI), Kappa’s coefficient, Aiken’ V coefficient, and content validity ratio (CVR)), which indicated high content validity for the selected items. This study provides a set of measurement survey items that can be used to evaluate WF management initiatives implemented in agri-food supply chains in future empirical studies.

10.
Atmospheric Chemistry and Physics ; 22(7):4853-4866, 2022.
Article in English | ProQuest Central | ID: covidwho-1786221

ABSTRACT

The outbreak of COVID-19 promoted strict restrictions to human activities in China, which led to a dramatic decrease in most air pollutant concentrations (e.g., PM2.5, PM10, NOx, SO2 and CO). However, an obvious increase in ozone (O3) concentrations was found during the lockdown period in most urban areas of China. In this study, we conducted field measurements targeting ozone and its key precursors by utilizing a novel proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS) in Changzhou, which is representative of the Yangtze River Delta (YRD) city cluster of China. We further applied the integrated methodology including machine learning, an observation-based model (OBM) and sensitivity analysis to obtain insights into the reasons causing the obvious increase in ozone. Major findings include the following: (1) by deweathered calculation, we found changes in precursor emissions contributed 1.46 ppbv to the increase in the observed O3 during the full-lockdown period in 2020, while meteorology constrained 3.0 ppbv of O3 in the full-lockdown period of 2019. (2) By using an OBM, we found that although a significant reduction in O3 precursors was observed during the full-lockdown period, the photochemical formation of O3 was stronger than that during the pre-lockdown period. (3) The NOx/VOC ratio dropped dramatically from 1.84 during the pre-lockdown to 0.79 in the full-lockdown period, which switched O3 formation from a VOC-limited regime to the boundary of a NOx- and VOC-limited regime. Additionally, box model results suggested that the decrease in the NOx/VOC ratio during the full-lockdown period could increase the mean O3 by 2.4 ppbv. Results of this study give insights into the relationship between O3 and its precursors in urban area and demonstrate reasons for the obvious increase in O3 in most urban areas of China during the COVID-19 lockdown period. This study also underlines the necessity of controlling anthropogenic oxygenated volatile organic compounds (OVOCs), alkenes and aromatics in the sustained campaign of reducing O3 pollution in China.

11.
Atmospheric Chemistry and Physics ; 22(6):4047-4073, 2022.
Article in English | ProQuest Central | ID: covidwho-1766081

ABSTRACT

This paper concerns an in-depth analysis of an exceptional incursion of mineral dust over southern Europe in late March 2020 (27–30 March 2020). This event was associated with an anomalous circulation pattern leading to several days of PM10 (particulate matter with an aerodynamic diameter less than 10 µm) exceedances in connection with a dust source located in central Asia;this is a rare source of dust for Europe, which is more frequently affected by dust outbreaks from the Sahara Desert. The synoptic meteorological configuration was analyzed in detail, and the aerosol evolution during the transit of the dust plume over northern Italy was assessed at high time resolution by means of optical particle counting at three stations, namely Bologna, Trieste, and Mt. Cimone, allowing for the revelation of the transport timing among the three locations. Back-trajectory analyses supported by Copernicus Atmosphere Monitoring Service (CAMS) maps allowed for the location of the mineral dust source area in the Aralkum region. Therefore, the event was analyzed by observing the particle number size distribution with the support of chemical composition analysis. It is shown that the PM10 exceedance recorded is associated with a large fraction of coarse particles, which is in agreement with mineral dust properties. Both the in situ number size distribution and the vertical distribution of the dust plume were cross-checked using lidar ceilometer and aerosol optical depth (AOD) data from two nearby stations and showed that the dust plume (in contrast to those originating from the Sahara Desert) traveled close to the ground (up to a height of about 2 km). The limited mixing layer height caused by high concentrations of absorbing and scattering aerosols caused the mixing of mineral dust with other locally produced ambient aerosols, thereby potentially increasing its morbidity effects.

12.
Development and Learning in Organizations: An International Journal ; 36(3):37-39, 2022.
Article in English | ProQuest Central | ID: covidwho-1741082

ABSTRACT

Purpose>This paper aims to review the latest management developments across the globe and pinpoint practical implications from cutting-edge research and case studies.Design/methodology/approach>This briefing is prepared by an independent writer who adds their own impartial comments and places the articles in context.Findings>Dimensions of organizational climate vary in their influence of how workers perceive the firm. Adopting an approach which combines psychological networks analysis and Thriving at Work constructs can help practitioners ascertain which dimensions have greatest scope to increase the level of organizational commitment among employees.Originality/value>The briefing saves busy executives and researchers hours of reading time by selecting only the very best, most pertinent information and presenting it in a condensed and easy-to-digest format.

13.
Sensors (Basel) ; 21(24)2021 Dec 16.
Article in English | MEDLINE | ID: covidwho-1592586

ABSTRACT

The fit of a lower limb prosthetic socket is critical for user comfort and the quality of life of lower limb amputees. Sockets are conventionally produced using hand-crafted patient-based casting techniques. Modern digital techniques offer a host of advantages to the process and ultimately lead to improving the lives of amputees. However, commercially available scanning equipment required is often expensive and proprietary. Smartphone photogrammetry could offer a low cost alternative, but there is no widely accepted imaging technique for prosthetic socket digitisation. Therefore, this paper aims to determine an optimal imaging technique for whole socket photogrammetry and evaluate the resultant scan measurement accuracy. A 3D printed transtibial socket was produced to create digital and physical twins, as reference models. The printed socket was photographed from 360 positions and simplified genetic algorithms were used to design a series of experiments, whereby a collection of photos were processed using Autodesk ReCap. The most fit technique was used to assess accuracy. The accuracy of the socket wall volume, surface area and height were 61.63%, 99.61% and 99.90%, respectively, when compared to the digital reference model. The scanned model had a wall thickness ranging from 2.075 mm at the top to 7.758 mm towards the base of the socket, compared to a consistent thickness of 2.025 mm in the control model. The technique selected did not show sufficient accuracy for clinical application due to the degradation of accuracy nearer to the base of the socket interior. However, using an internal wall thickness estimation, scans may be of sufficient accuracy for clinical use; assuming a uniform wall thickness.


Subject(s)
Artificial Limbs , Smartphone , Humans , Photogrammetry , Prosthesis Design , Quality of Life
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