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1.
Sci Rep ; 12(1): 11645, 2022 07 08.
Article in English | MEDLINE | ID: mdl-35804087

ABSTRACT

The emergence of the level 3 automated vehicles (L3 AVs) can enable drivers to be completely disengaged from driving and safely perform other non-driving related tasks, but sometimes their takeover of control of the vehicle is required. The takeover of control is an important human-machine interaction in L3 AVs. However, little research has focused on investigating the effect of gender on takeover performance. In order to fill this research gap, a driving simulator study with 76 drivers (33 females and 43 males) was conducted. The participants took over control from L3 AVs, and the timing and quality of takeover were measured. The results show that although there was no significant difference in most of the measurements adopted to quantify takeover performance between female and male. Gender did affect takeover performance slightly, with women exhibited slightly better performance than men. Compared to men, women exhibited a smaller percentage of hasty takeovers and slightly faster reaction times as well as slightly more stable operation of the steering wheel. The findings highlight that it is important for both genders to recognise they can use and interact with L3 AVs well, and more hands-on experience and teaching sessions could be provided to deepen their understanding of L3 AVs. The design of the car interiors of L3 AVs should also take into account gender differences in the preferences of users for different non-driving related tasks.


Subject(s)
Automobile Driving , Autonomous Vehicles , Psychomotor Performance , Automobile Driving/psychology , Female , Humans , Male , Psychomotor Performance/physiology , Reaction Time/physiology , Sex Factors
2.
J Air Waste Manag Assoc ; 71(9): 1085-1101, 2021 09.
Article in English | MEDLINE | ID: mdl-33764280

ABSTRACT

Countries around the world introduced strict restrictions on movement and activities known as 'lockdowns' to restrict the spread of the novel coronavirus disease (COVID-19) from the end of 2019. A sudden improvement in air quality was observed globally as a result of these lockdowns. To provide insight into the changes in air pollution levels in response to the COVID-19 restrictions we have compared surface air quality data in Delhi during four phases of lockdown and the first phase of the restriction easing period (25 March to 30 June 2020) with data from a baseline period (2018-2019). Simultaneously, short-term exposure of PM2.5 and O3 attributed premature mortality were calculated to understand the health benefit of the change in air quality. Ground-level observations in Delhi showed that concentrations of PM10, PM2.5 and NO2 dropped substantially in 2020 during the overall study period compared with the same period in previous years, with average reductions of ~49%, ~39%, and ~39%, respectively. An overall lower reduction in O3 of ~19% was observed for Delhi. A slight increase in O3 was found in Delhi's industrial and traffic regions. The highest peak of the diurnal variation decreased substantially for all the pollutants at every phase. The decrease in PM2.5 and O3 concentrations in 2020, prevented 904 total premature deaths, a 60% improvement when compared to the figures for 2018-2019. The restrictions on human activities during the lockdown have reduced anthropogenic emissions and subsequently improved air quality and human health in one of the most polluted cities in the world.Implications: I am submitting herewith the manuscript entitled "Unprecedented Reduction in Air Pollution and Corresponding Short-term Premature Mortality Associated with COVID-19 Forced Confinement in Delhi, India" for potential publishing in your journal.The novelty of this research lies in: (1) we utilized ground-level air quality data in Delhi during four phases of lockdown and the first phase of unlocking period (25th March to 30th June) for 2020 as well as data from the baseline period (2018-2019) to provide an early insight into the changes in air pollution levels in response to the COVID-19 pandemic, (2) Chatarize the change of diurnal variation of the pollutants and (3) we assess the health risk due to PM2.5 and O3. Results from ground-level observations in Delhi showed that concentrations of PM10, PM2.5 and NO2 substantially dropped in 2020 during the overall study period compared to the similar period in previous years, with an average reduction of ~49%, ~39%, and ~39%, respectively. In the case of O3, the overall reduction was observed as ~19% in Delhi, while a slight increase was found in industrial and traffic regions. And consequently, the highest peak of the diurnal variation decreased substantially for all the pollutants. The health impact assessment of the changes in air quality indicated that 904 short-term premature deaths (~60%) were prevented due to the decline in PM2.5 and O3 concentrations in the study period. The restrictions on human activities during the lockdown have reduced the anthropogenic emissions and subsequently improved air quality and human health in one of the most polluted cities in the world.


Subject(s)
Air Pollutants/analysis , Air Pollutants/poisoning , Air Pollution/adverse effects , Air Pollution/analysis , COVID-19/prevention & control , Communicable Disease Control , Mortality, Premature , COVID-19/epidemiology , Cities/epidemiology , Environmental Monitoring , Humans , India/epidemiology , Pandemics , Particulate Matter/analysis , Particulate Matter/poisoning
3.
RSC Adv ; 10(61): 37391-37408, 2020 Oct 07.
Article in English | MEDLINE | ID: mdl-35521230

ABSTRACT

The production of methane-rich biogas from the anaerobic digestion (AD) of microalgae is limited by an unfavorable biomass carbon-to-nitrogen (C/N) ratio; however, this may be ameliorated using a co-digestion strategy with carbon-rich feedstocks. For reliable plant operation, and to improve the economics of the process, secure co-feedstock supply (ideally as a waste-stream) is important. To this end, this study investigated the feasibility of co-digesting microalgae (Chlorella vulgaris) with potato processing waste (potato discarded parts, PPWdp; potato peel, PPWp) and glycerol, while monitoring the response of the methanogenic community. In this semi-continuous study, glycerol (1 and 2% v/v) added to mixtures of C. vulgaris : PPWdp enhanced the specific methane yields the most, by 53-128%, whilst co-digestion with mixtures of C. vulgaris : PPWp enhanced the methane yields by 62-74%. The microbial communities diverged markedly over operational time, and to a lesser extent in response to glycerol addition. The acetoclast Methanosaeta was abundant in all treatments but was replaced by Methanosarcina in the potato peel with glycerol treatment due to volatile fatty acid (VFA) accumulation. Our findings demonstrate that the performance of microalgae co-digestion is substantially improved by the addition of glycerol as an additional co-feedstock. This should improve the economic case for anaerobically digesting microalgae as part of wastewater treatment processes and/or the terminal step of a microalgae biorefinery.

4.
ChemistryOpen ; 5(4): 269, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27547633

ABSTRACT

Invited for this month's cover are researchers from the Naval Air Warfare Center Weapons Division (USA). The cover picture shows the elusive symmetric molecule bis (tetrahydrofurfuryl) ether (BTHFE) in the making. For more details, read the full text of the Communication at 10.1002/open.201600013.

5.
ChemistryOpen ; 5(4): 297-300, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27547636

ABSTRACT

Despite the availability of a large number of alkyl tetrahydrofurfuryl ethers that have a wide range of applications, pure bis(tetrahydrofurfuryl) ether (BTHFE) has not been previously synthesized. Here, we report the synthesis of BTHFE (consisting of the RR, SS, and meso stereoisomers) at greater than 99 % purity from tetrahydrofurfuryl alcohol, using (tetrahydrofuran-2-yl)methyl methanesulfonate as an intermediate. Additionally, we demonstrate that BTHFE can be used as a non-volatile solvent in poly(3,4-propylenedioxythiophene)-based supercapacitors. Supercapacitor devices employing solutions of the ionic liquid 1-ethyl-3-methyl-imidizolium bis(trifluoromethylsulfonyl)imide in BTHFE display similar performances to those prepared by using the neat ionic liquid as an electrolyte, although solution-based devices exhibit a somewhat higher resistance.

6.
Environ Int ; 89-90: 248-60, 2016.
Article in English | MEDLINE | ID: mdl-26922565

ABSTRACT

Hydraulic fracturing (fracking) has been used extensively in the US and Canada since the 1950s and offers the potential for significant new sources of oil and gas supply. Numerous other countries around the world (including the UK, Germany, China, South Africa, Australia and Argentina) are now giving serious consideration to sanctioning the technique to provide additional security over the future supply of domestic energy. However, relatively high population densities in many countries and the potential negative environmental impacts that may be associated with fracking operations has stimulated controversy and significant public debate regarding if and where fracking should be permitted. Road traffic generated by fracking operations is one possible source of environmental impact whose significance has, until now, been largely neglected in the available literature. This paper therefore presents a scoping-level environmental assessment for individual and groups of fracking sites using a newly-created Traffic Impacts Model (TIM). The model produces estimates of the traffic-related impacts of fracking on greenhouse gas emissions, local air quality emissions, noise and road pavement wear, using a range of hypothetical fracking scenarios to quantify changes in impacts against baseline levels. Results suggest that the local impacts of a single well pad may be short duration but large magnitude. That is, whilst single digit percentile increases in emissions of CO2, NOx and PM are estimated for the period from start of construction to pad completion (potentially several months or years), excess emissions of NOx on individual days of peak activity can reach 30% over baseline. Likewise, excess noise emissions appear negligible (<1dBA) when normalised over the completion period, but may be considerable (+3.4dBA) in particular hours, especially in night-time periods. Larger, regional scale modelling of pad development scenarios over a multi-decade time horizon give modest CO2 emissions that vary between 2.5 and 160.4kT, dependent on the number of wells, and individual well fracking water and flowback waste requirements. The TIM model is designed to be adaptable to any geographic area where the required input data are available (such as fleet characteristics, road type and quality), and we suggest could be deployed as a tool to help reach more informed decisions regarding where and how fracking might take place taking into account the likely scale of traffic-related environmental impacts.


Subject(s)
Air Pollutants/analysis , Environmental Monitoring/methods , Hydraulic Fracking , Models, Theoretical , Noise , Vehicle Emissions/analysis , United Kingdom
7.
Materials (Basel) ; 7(12): 8088-8104, 2014 Dec 17.
Article in English | MEDLINE | ID: mdl-28788292

ABSTRACT

In this study, an electroactive polymer (EAP), poly(2,5-bis(N-methyl-N-hexylamino)phenylene vinylene) (BAM-PPV) was investigated as a potential alternative surface pretreatment for hexavalent chromium (Cr(VI))-based aerospace coatings. BAM-PPV was tested as a pretreatment coating on an aerospace aluminum alloy (AA2024-T3) substrate in combination with a non-Cr(VI) epoxy primer and a polyurethane Advanced Performance Coating (APC) topcoat. This testing was undertaken to determine BAM-PPV's adhesion, corrosion-inhibition, compatibility and survivability in laboratory testing and during outdoor field-testing. BAM-PPV showed excellent adhesion and acceptable corrosion performance in laboratory testing. The BAM-PPV aerospace coating system (BAM-PPV, non-Cr(VI) epoxy primer and polyurethane APC topcoat) was field tested for one year on the rear hatch door of the United States Air Force C-5 cargo plane. After one year of field testing there was no evidence of delamination or corrosion of the BAM-PPV aerospace coating system.

8.
Sci Total Environ ; 386(1-3): 65-82, 2007 Nov 01.
Article in English | MEDLINE | ID: mdl-17716708

ABSTRACT

Measurements of urban particle number concentrations and size distributions in the range 5-1000 nm were taken at elevated (roof-level) and roadside sampling sites on Narborough Road in Leicester, UK, along with simultaneous measurements of traffic, NO(x), CO and 1,3-butadiene concentrations and meteorological parameters. A fitting program was used to determine the characteristics of up to five modal groups present in the particle size distributions. All particle modal concentrations peaked during the morning and evening rush hours. Additional events associated with the smallest mode, that were not observed to be connected to primary emissions, were also present suggesting that this mode consisted of newly formed secondary particles. These events included peaks in concentration which coincided with peaks in solar radiation, and lower concentrations of the larger modes. Investigation into the relationships between traffic flow and occupancy indicated three flow regimes; free-flow, unstable and congested. During free-flow conditions, positive linear relationships existed between traffic flow and particle modal number concentrations. However, during unstable and congested periods, this relationship was shown to break-down. Similar trends were observed for concentrations of the gas phase pollutants NO(x), CO and 1,3-butadiene. Strong linear relationships existed between NO(x), CO, 1,3-butadiene concentrations, nucleation and Aitken mode concentrations at both sampling locations, indicating a local traffic related emission source. At the roadside, both nucleation and Aitken mode are best represented by a decreasing exponential function with wind speed, whereas at the roof-level this relationship only occurred for Aitken mode particles. The differing relationships at the two sampling locations are most likely due to a combination of meteorological factors and distance from the local emission source.


Subject(s)
Environmental Monitoring/methods , Motor Vehicles , Particulate Matter/analysis , Vehicle Emissions/analysis , Cities , Gases , Particle Size , Time Factors , United Kingdom , Wind
9.
Ann Biomed Eng ; 33(6): 780-97, 2005 Jun.
Article in English | MEDLINE | ID: mdl-16078618

ABSTRACT

A numerical model of thrombosis/thromboembolism (T/TE) is presented that predicts the progression of thrombus growth and thromboembolization in low-shear devices (hemodialyzers, oxygenators, etc.). Coupled convection-diffusion-reaction equations were solved to predict velocities, platelet agonist (ADP, thromboxane A2, and thrombin) concentrations, agonist-induced and shear-induced platelet activation, and platelet transport and adhesion to biomaterial surfaces and adherent platelets (hence, thrombus growth). Single-platelet and thrombus embolization were predicted from shear forces and surface adhesion strengths. Values for the platelet-biomaterial reaction constant and the platelet adhesion strength were measured in specific experiments, but all other parameter values were obtained from published sources. The model generated solutions for sequential time steps, while adjusting velocity patterns to accommodate growing surface thrombi. Heparinized human blood was perfused (0.75 ml/min) through 580 microm-ID polyethylene flow cells with flow contractions (280 microm-ID). Thrombus initiation, growth, and embolization were observed with videomicroscopy, while embolization was confirmed by light scattering, and platelet adhesion was determined by scanning electron microscopy. Numerical predictions and experimental observations were similar in indicating: 1) the same three thrombotic locations in the flow cell and the relative order of thrombus development in those locations, 2) equal thrombus growth rates on polyethylene and silicon rubber (in spite of differing overall T/TE), and 3) similar effects of flow rate (1.5 ml/min versus 0.75 ml/min) on platelet adhesion and thrombosis patterns.


Subject(s)
Blood Vessel Prosthesis , Computer Simulation , Models, Cardiovascular , Platelet Adhesiveness , Thromboembolism/physiopathology , Blood Flow Velocity , Blood Vessel Prosthesis/adverse effects , Humans , Shear Strength
10.
Pharos Alpha Omega Alpha Honor Med Soc ; 67(4): 48; author reply 48, 2004.
Article in English | MEDLINE | ID: mdl-15625953
11.
J Biomed Opt ; 8(1): 70-9, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12542382

ABSTRACT

The characteristics and capabilities of a light-scattering microemboli detector (LSMD) are delineated by detailing its state-of-the-art configuration, by discussing the theoretical and empirical aspects of instrument calibration, and by summarizing various experimental studies that have benefited from this instrument. In the past, thromboembolism, which often results when blood contacts medical devices, has eluded scientific scrutiny due to the absence of instruments that could detect and quantify thromboemboli in circulating blood. More recently, the ability of the LSMD to provide continuous, noninvasive detection of thromboemboli in whole blood (meaning that the LSMD probe does not contact the blood) was exploited in various in vitro and ex vivo models to explore thromboembolic phenomena. Through this work, the LSMD evolved as a sensitive and an economical research tool for the study of thromboembolic phenomena.


Subject(s)
Optics and Photonics/instrumentation , Thromboembolism/blood , Thromboembolism/diagnosis , Aneurysm/blood , Aneurysm/therapy , Animals , Cattle , Equipment Design , Heart-Assist Devices/adverse effects , Hemodynamics , Humans , In Vitro Techniques , Light , Microspheres , Models, Theoretical , Scattering, Radiation , Sheep , Thromboembolism/etiology
12.
Am J Hematol ; 69(1): 45-55, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11835331

ABSTRACT

Cold-induced platelet aggregation (CIPA) in PRP has previously been documented in connection with platelet preservation (4-15 degrees C). This report describes hypothermia-induced platelet aggregation (HIPA) in whole blood and at temperatures used in open-heart surgery (24-32 degrees C). HIPA (specifically, the formation of occlusive aggregates) was studied in human whole blood. Fresh heparinized (1.5 U/ml) human blood was cooled and maintained at target temperatures (15, 20, 24, 28, 32, or 37 degrees C) as it flowed (1 ml/min) through 75-cm long 1/32 inches internal diameter polymer conduit. The formation of aggregates in the tubing was verified using optical video microscopy and was quantified by a light-scattering method and a constant-pressure filtration method. Donors were tested at least twice at each target temperature and were classified into three separate response regimes (Low, Medium, and High) on the basis of the number of aggregates and the duration of their appearance. The screening of 121 donors (average age 22.3 +/- 4.3 years) for HIPA at 24 degrees C (the temperature of maximum response) indicated 14% High Responders, 18% Medium Responders, and 68% Low Responders. HIPA was inhibited by EDTA, citrate, PGE1, and Tirofiban, but not by aspirin, and it was enhanced by elevated heparin levels. HIPA was consistently noted in the blood of a subpopulation of donors, and the associated platelet aggregates in the blood of High Responders were rigid and occlusive. It is postulated that such aggregates may contribute to cognitive dysfunction noted in patients undergoing hypothermic open-heart surgery, and that postulus is being investigated.


Subject(s)
Heparin/blood , Hypothermia/blood , Platelet Aggregation , Tyrosine/analogs & derivatives , Alprostadil/pharmacology , Anemia, Hemolytic, Autoimmune/diagnosis , Aspirin/pharmacology , Blood Cell Count , Citric Acid/pharmacology , Cold Temperature , Edetic Acid/pharmacology , Filtration , Hemorheology , Heparin/pharmacology , Humans , Light , Models, Biological , Platelet Aggregation/drug effects , Platelet Aggregation Inhibitors/pharmacology , Pressure , Protamines/blood , Scattering, Radiation , Tirofiban , Tyrosine/pharmacology
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