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1.
Energy Fuels ; 38(10): 8829-8841, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38774062

ABSTRACT

While today's biomass-based diesel fuels are used at relatively low blend levels in petroleum diesel, decarbonization of the heavy-duty trucking and off-road sectors is driving increasing use of higher level blends and the combination of hydroprocessing-derived renewable diesel (RD) with biodiesel (fatty acid methyl esters) to create a 100% renewable fuel. However, little data are available on the properties of biodiesel blends over 20 vol % into RD or conventional diesel, despite the potential for properties to fall well outside the normal range for diesel fuels. Here, we evaluate the properties of 20-80% blends of a soy-derived biodiesel into RD and petroleum diesel. Properties measured were flash point, cloud point, cetane number, surface tension, density, kinematic viscosity, distillation curve, lower heating value, water content, water solubility in the fuel, lubricity, and oxidation stability. Density and viscosity were measured over a wide temperature range. A key objective was to reveal properties that might limit blending of biodiesel and any differences between biodiesel blends into RD versus petroleum diesel and to understand research needed to advance the use of high-level blends and 100% renewable fuel. Properties that may limit blending include the cloud point, viscosity, distillation curve, and oxidation stability. Meeting cloud point requirements can be an issue for all distillate fuels. For biodiesel, reducing the blend level and use of lower cloud point hydrocarbon blendstocks, such as No. 1 diesel or kerosene, can be used in winter months. Alternatively, a heated fuel system that allows for starting the vehicle on conventional diesel before switching to pure biodiesel (B100) or a high-level blend has been successfully demonstrated in the literature. Some biodiesels can have kinematic viscosity above the upper limit for diesel fuels (4.1 mm2/s), which will limit the amount that can be blended. Biodiesel boils in a narrow range at the very high end of the No. 2 diesel range. Additional research is needed to understand how the high T90 of B100 and high-level blends and the very low distillation range of B100, some RD samples, and high-level biodiesel blends impact lube oil dilution, engine deposits, and diesel oxidation catalyst light-off. Blending with No. 1 diesel or kerosene or biodiesel-specific engine calibrations may mitigate these issues. Oxidation stability of higher level blends is poorly understood but may be addressed through the increased use of antioxidant additives. Finally, high-level biodiesel blends and B100 will have significantly higher density, viscosity, and surface tension compared to conventional diesel. In combination with the high boiling point, these properties may impact fuel spray atomization and evaporation, and additional research is needed in this area.

2.
Semin Neurol ; 43(3): 419-431, 2023 06.
Article in English | MEDLINE | ID: mdl-37549691

ABSTRACT

Chronic neck and back pain are two of the most common and disabling complaints seen in primary care and neurology practices. Most commonly these come in the form of cervical and lumbar radiculopathy, lumbar spinal stenosis, and cervical and lumbar facet arthropathy. Treatment options are widespread and include nonpharmacological, pharmacological, surgical, and interventional options. The focus of this review will be to discuss the most common interventional procedures performed for chronic cervical and lumbar back pain, common indications for performing these interventions, as well as associated benefits and risks. These interventions alone may not suffice to improve the quality of life in those suffering from chronic pain. However, an understanding of the interventional pain options available and the evidence behind performing these interventions can help providers incorporate these into a multimodal approach to provide effective pain management that may allow patients an improved quality of life.


Subject(s)
Chronic Pain , Low Back Pain , Humans , Pain Management/methods , Quality of Life , Back Pain/therapy , Chronic Pain/therapy
3.
Clin Exp Dent Res ; 8(2): 583-588, 2022 04.
Article in English | MEDLINE | ID: mdl-35157789

ABSTRACT

BACKGROUND: Concern that facial swelling after dental extractions will spoil the fit of radiotherapy masks in head and neck cancer patients leads to the current practice of delay making of mask production (and therefore the start of radiotherapy) for several days or longer. However, there is little data on how extensive facial swelling is after dental extraction. AIM: To assess the degree of facial swelling in a group of adult patients attending Newcastle Dental School for routine dental extractions. MATERIALS AND METHODS: Seventeen dental extraction patients underwent three-dimensional photography using the 3dMDFace® system at 1-week preop, immediately preop, and at 48-h postop. We recorded demographic data, teeth extracted, and methods. Facial volume change was assessed using 3dMD Vultus® software. Two reviewers ran the data through the 3dMD Vultus® software independently. We used Student's t-test to assess significance. RESULTS: Twelve patients were included in the final analysis. There was no significant difference in the difference between the two preoperative measurements and the preoperative versus postoperative difference (Wilcoxon signed-rank test: Reviewer 1: p = .31. and Reviewer 2: p = .10). Thus, mean facial swelling was less than the threshold for significant swelling which was deemed to be 15 cm3 . CONCLUSION: Facial swelling following dental extraction may not be sufficient in itself to justify the current delays in mask production and subsequent delivery of radiotherapy. Further definitive studies are needed to optimize how dental extractions should be timed within head and neck cancer care pathways.


Subject(s)
Face , Head and Neck Neoplasms , Adult , Head and Neck Neoplasms/radiotherapy , Head and Neck Neoplasms/surgery , Humans , Photography , Pilot Projects , Tooth Extraction/adverse effects
4.
Neurohospitalist ; 11(3): 229-234, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34163548

ABSTRACT

BACKGROUND AND PURPOSE: While the successful provision of telestroke care has been well documented in the literature, studies on the impact of comprehensive teleneurology service (TN) to hospital measures are lacking. We evaluated 3 traditional health services metrics of hospital performance: time from consult request to consult completion, inpatient length of stay (LOS), and the rate of patients transferred for tertiary care. METHODS: Medical records (n = 899) from 3 community hospitals and our TN consultation database were retrospectively reviewed during the 2 years before (n = 703, 3 hospitals) and 4 months (n = 2 hospitals) to 2 years (n = 1 hospital) after implementation (n = 196) of a TN program for routine and urgent consult requests. Consult order time, consult completion time, total length of stay and discharge disposition were compared across the pre-TN implementation group, which consisted of in-person consultations and the post-TN implementation group, which consisted of TN consultations only. RESULTS: After TN implementation, median length of stay decreased 28% (3.9 vs. 2.8 days, p < 0.0001) and median time from consult order to consult completion decreased by 74% across all diagnoses (5.8 vs. 1.5 hours, p < 0.0001). There were no significant differences in the percentage of patients discharged home (52.3% vs. 56.1%, p = 0.10) or transferred to tertiary care (6.1% to 9.2%, p = 0.10). CONCLUSIONS: Implementation of TN program was associated with significant reductions in LOS and time to consultation completion without an increase in shunting of patients to more advanced facilities. Further research is warranted to confirm these findings in independent cohorts and other models of teleneurology delivery.

5.
Ment Health Clin ; 11(3): 187-193, 2021 May.
Article in English | MEDLINE | ID: mdl-34026394

ABSTRACT

INTRODUCTION: Access to pimavanserin, the only Parkinson disease-related psychosis treatment approved by the FDA, is restricted by insurance requirements, a limited distribution network, and high costs. Following initiation, patients require monitoring for safety and effectiveness. The primary objective of this study was to evaluate impact of specialty pharmacist (SP) integration on time to insurance approval. Additionally, we describe a pharmacist-led monitoring program. METHODS: This was a single-center, retrospective study of adults prescribed pimavanserin by the neurology clinic from June 2016 to June 2018. Patients receiving pimavanserin externally or through clinical trials were excluded. Pre- (June 2016 to December 2016) and post-SP integration (January 2017 to June 2018) periods were assessed. Proportional odds logistic regression was performed to test association of approval time with patient characteristics (age, gender, insurance type) postintegration. Interventions were categorized as clinical care, care coordination, management of adverse event, or adherence. RESULTS: We included 94 patients (32 preintegration, 62 postintegration), 80% male (n = 75) and 96% white (n = 90) with a mean age of 73 years. Median time to approval was 22 days preintegration and 3 days postintegration. Higher rates of approval (81% vs 95%) and initiation (78% vs 94%) were observed postintegration. Proportional odds logistic regression suggested patients with commercial insurance were likely to have longer time to approval compared with patients with Medicare/Medicaid (odds ratio 7.1; 95% confidence interval: 1.9, 26.7; P = .004). Most interventions were clinical (51%, n = 47) or care coordination (42%, n = 39). CONCLUSION: Median time to approval decreased postintegration. The SP performed valuable monitoring and interventions.

6.
J Hazard Mater ; 400: 123198, 2020 12 05.
Article in English | MEDLINE | ID: mdl-32585513

ABSTRACT

The hazards to health and the environment associated with the transportation sector include smog, particulate matter, and greenhouse gas emissions. Conversion of lignocellulosic biomass into biofuels has the potential to provide significant amounts of infrastructure-compatible liquid transportation fuels that reduce those hazardous materials. However, the development of these technologies is inefficient, due to: (i) the lack of a priori fuel property consideration, (ii) poor shared vocabulary between process chemists and fuel engineers, and (iii) modern and future engines operating outside the range of traditional autoignition metrics such as octane or cetane numbers. In this perspective, we describe an approach where we follow a "fuel-property first" design methodology with a sequence of (i) identifying the desirable fuel properties for modern engines, (ii) defining molecules capable of delivering those properties, and (iii) designing catalysts and processes that can produce those molecules from a candidate feedstock in a specific conversion process. Computational techniques need to be leveraged to minimize expenses and experimental efforts on low-promise options. This concept is illustrated with current research information available for biomass conversion to fuels via catalytic fast pyrolysis and hydrotreating; outstanding challenges and research tools necessary for a successful outcome are presented.


Subject(s)
Biofuels , Pyrolysis , Biomass , Catalysis , Particulate Matter
7.
Environ Sci Process Impacts ; 22(7): 1461-1474, 2020 Jul 22.
Article in English | MEDLINE | ID: mdl-32558863

ABSTRACT

With an ongoing interest in displacing petroleum-based sources of energy with biofuels, there is a need to measure and model the formation and composition of secondary organic aerosol (SOA) from organic compounds present in biofuels. We performed chamber experiments to study SOA formation from four recently identified biofuel molecules and mixtures and commercial gasoline under high NOx conditions: diisobutylene, cyclopentanone, an alkylfuran mixture, and an ethanol-to-hydrocarbon (ETH) mixture. Cyclopentanone and diisobutylene had a significantly lower potential to form SOA compared to commercial gasoline, with SOA mass yields lower than or equal to 0.2%. The alkylfuran mixture had an SOA mass yield (1.6%) roughly equal to that of gasoline (2.0%) but ETH had an average SOA mass yield (11.5%) that was six times higher than that of gasoline. We used a state-of-the-science model to parameterize or simulate the SOA formation in the chamber experiments while accounting for the influence of vapor wall losses. Simulations performed with vapor wall losses turned off and at atmospherically relevant conditions showed that the SOA mass yields were higher than those measured in the chamber at the same photochemical exposure and were also higher than those estimated using a volatility basis set that was fit to the chamber data. The modeled SOA mass yields were higher primarily because they were corrected for vapor wall losses to the Teflon® chamber.


Subject(s)
Aerosols , Air Pollutants , Gasoline , Biofuels , Gases , Organic Chemicals
8.
Proc Natl Acad Sci U S A ; 116(52): 26421-26430, 2019 Dec 26.
Article in English | MEDLINE | ID: mdl-31843899

ABSTRACT

Lignocellulosic biomass offers a renewable carbon source which can be anaerobically digested to produce short-chain carboxylic acids. Here, we assess fuel properties of oxygenates accessible from catalytic upgrading of these acids a priori for their potential to serve as diesel bioblendstocks. Ethers derived from C2 and C4 carboxylic acids are identified as advantaged fuel candidates with significantly improved ignition quality (>56% cetane number increase) and reduced sooting (>86% yield sooting index reduction) when compared to commercial petrodiesel. The prescreening process informed conversion pathway selection toward a C11 branched ether, 4-butoxyheptane, which showed promise for fuel performance and health- and safety-related attributes. A continuous, solvent-free production process was then developed using metal oxide acidic catalysts to provide improved thermal stability, water tolerance, and yields. Liter-scale production of 4-butoxyheptane enabled fuel property testing to confirm predicted fuel properties, while incorporation into petrodiesel at 20 vol % demonstrated 10% improvement in ignition quality and 20% reduction in intrinsic sooting tendency. Storage stability of the pure bioblendstock and 20 vol % blend was confirmed with a common fuel antioxidant, as was compatibility with elastomeric components within existing engine and fueling infrastructure. Technoeconomic analysis of the conversion process identified major cost drivers to guide further research and development. Life-cycle analysis determined the potential to reduce greenhouse gas emissions by 50 to 271% relative to petrodiesel, depending on treatment of coproducts.

9.
Br Dent J ; 226(7): 498-502, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30980004

ABSTRACT

Background and aim Unscheduled dental attendances (UDA) and the associated morbidity can cause individual distress, disrupt military effectiveness and have broader societal impacts. Preventing future dental morbidity is an essential component of dentistry. This, the largest study of its type, aimed to examine the relationship between clinical and demographic variables and UDA, and to quantify how well military dental risk categorisation predicts subsequent UDA events. Methods This is a retrospective cohort analysis of a clinical dataset containing 175,558 service personnel over an 11-month period. Statistical methods examined: sensitivity and specificity of the existing NATO 'Dental fitness classification system' (NATO Cat) in predicting UDA, relative risk (RR) of UDA by selected variables, Kaplan-Meier failure analysis and multivariate analysis. Results A total of 16,722 UDA events were recorded, the majority (66.7%) were due to caries, periapical pathology and fractured teeth or restorations, or a combination thereof. NATO Cat yielded poor predictive sensitivity (sensitivity 10%, specificity 93%). NATO Cat 3 (RR 1.47), age group (RR 1.06-2.05), gender (RR 1.46) and DMFT category (RR 1.09-3.05), were all significantly associated with increased UDA. The RR of UDA increased by 5% (RR 1.05) for each additional DMFT increment in a logistic regression model. Conclusions After adjusting for confounding variables, DMFT was significantly associated with UDA events. This study indicates that, even when treatment need has been met, a residual risk remains that is directly related to exposure to dental disease and operative dentistry. Strategies which prevent downstream operative treatment need and increases in DMFT may also reduce future UDA. UDA may be a useful quality outcome indicator for the success of NHS dental services in securing oral health.


Subject(s)
Dental Caries , Dentistry, Operative , Dental Care , Humans , Oral Health , Retrospective Studies
10.
J Phys Chem A ; 121(29): 5475-5486, 2017 Jul 27.
Article in English | MEDLINE | ID: mdl-28678503

ABSTRACT

Oxygenated biofuels provide a renewable, domestic source of energy that can enable adoption of advanced, high-efficiency internal combustion engines, such as those based on homogeneously charged compression ignition (HCCI). Of key importance to such engines is the cetane number (CN) of the fuel, which is determined by the autoignition of the fuel under compression at relatively low temperatures (550-800 K). For the plethora of oxygenated biofuels possible, it is desirable to know the ignition delay times and the CN of these fuels to help guide conversion strategies so as to focus efforts on the most desirable fuels. For alkanes, the chemical pathways leading to radical chain-branching reactions giving rise to low-temperature autoignition are well-known and are highly coincident with the buildup of reactive radicals such as OH. Key in the mechanisms leading to chain branching are the addition of molecular oxygen to alkyl radicals and the rearrangement and dissociation of the resulting peroxy radials. Prediction of the temperature and pressure dependence of reactions that lead to the buildup of reactive radicals requires a detailed understanding of the potential energy surfaces (PESs) of these reactions. In this study, we used quantum mechanical modeling to systematically compare the effects of oxygen functionalities on these PESs and associated kinetics so as to understand how they affect experimental trends in autoignition and CN. The molecules studied here include pentane, pentanol, pentanal, 2-heptanone, methylpentyl ether, methyl hexanoate, and pentyl acetate. All have a saturated five-carbon alkyl chain with an oxygen functional group attached to the terminal carbon atom. The results of our systematic comparison may be summarized as follows: (1) Oxygen functionalities activate C-H bonds by lowering the bond dissociation energy (BDE) relative to alkanes. (2) The R-OO bonds in peroxy radicals adjacent to carbonyl groups are weaker than corresponding alkyl systems, leading to dissociation of ROO• radicals and reducing reactivity and hence CN. (3) Hydrogen atom transfer in peroxy radicals is important in autoignition, and low barriers for ethers and aldehydes lead to high CN. (4) Peroxy radicals formed from alcohols have low barriers to form aldehydes, which reduce the reactivity of the alkyl radical. These findings for the formation and reaction of alkyl radicals with molecular oxygen explain the trend in CN for these common biofuel functional groups.

12.
Br J Oral Maxillofac Surg ; 54(6): 697-9, 2016 Jul.
Article in English | MEDLINE | ID: mdl-26708800

ABSTRACT

Oral blood blisters and purpura are rare features of primary systemic amyloidosis (amyloid light-chain (AL) amyloidosis). We report a case in which these unusual presentations led to a diagnosis of amyloidosis, which enabled effective treatment before organ failure.


Subject(s)
Immunoglobulin Light-chain Amyloidosis/diagnosis , Purpura/etiology , Humans , Immunoglobulin Light-chain Amyloidosis/complications
13.
Chemosphere ; 104: 126-33, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24268344

ABSTRACT

Combustion emissions from diesel engines emit particulate matter which deposits within the lungs. Alveolar macrophages (AMs) encounter the particles and attempt to engulf the particles. Emissions particles from diesel combustion engines have been found to contain diverse biologically active components including metals and polyaromatic hydrocarbons which cause adverse health effects. However little is known about AM response to particles from the incorporation of biodiesel. The objective of this study was to examine the toxicity in Wistar Kyoto rat AM of biodiesel blend (B20) and low sulfur petroleum diesel (PDEP) exhaust particles. Particles were independently suspended in media at a range of 1-500µgmL(-1). Results indicated B20 and PDEP initiated a dose dependent increase of inflammatory signals from AM after exposure. After 24h exposure to B20 and PDEP gene expression of cyclooxygenase-2 (COX-2) and macrophage inflammatory protein 2 (MIP-2) increased. B20 exposure resulted in elevated prostaglandin E2 (PGE2) release at lower particle concentrations compared to PDEP. B20 and PDEP demonstrated similar affinity for sequestration of PGE2 at high concentrations, suggesting detection is not impaired. Our data suggests PGE2 release from AM is dependent on the chemical composition of the particles. Particle analysis including measurements of metals and ions indicate B20 contains more of select metals than PDEP. Other particle components generally reduced by 20% with 20% incorporation of biodiesel into original diesel. This study shows AM exposure to B20 results in increased production of PGE2in vitro relative to diesel.


Subject(s)
Biofuels/toxicity , Macrophages, Alveolar/drug effects , Particulate Matter/toxicity , Petroleum/toxicity , Vehicle Emissions/toxicity , Animals , Biofuels/analysis , Cells, Cultured , Dinoprostone/metabolism , Macrophages, Alveolar/metabolism , Male , Particulate Matter/analysis , Petroleum/analysis , Rats , Vehicle Emissions/analysis
14.
Environ Sci Technol ; 47(23): 13865-72, 2013 Dec 03.
Article in English | MEDLINE | ID: mdl-24180630

ABSTRACT

Certification gasoline was splash blended with alcohols to produce four blends: ethanol (16 vol%), n-butanol (17 vol%), i-butanol (21 vol%), and an i-butanol (12 vol%)/ethanol (7 vol%) mixture; these fuels were tested in a 2009 Honda Odyssey (a Tier 2 Bin 5 vehicle) over triplicate LA92 cycles. Emissions of oxides of nitrogen, carbon monoxide, non-methane organic gases (NMOG), unburned alcohols, carbonyls, and C1-C8 hydrocarbons (particularly 1,3-butadiene and benzene) were determined. Large, statistically significant fuel effects on regulated emissions were a 29% reduction in CO from E16 and a 60% increase in formaldehyde emissions from i-butanol, compared to certification gasoline. Ethanol produced the highest unburned alcohol emissions of 1.38 mg/mile ethanol, while butanols produced much lower unburned alcohol emissions (0.17 mg/mile n-butanol, and 0.30 mg/mile i-butanol); these reductions were offset by higher emissions of carbonyls. Formaldehyde, acetaldehyde, and butyraldehyde were the most significant carbonyls from the n-butanol blend, while formaldehyde, acetone, and 2-methylpropanal were the most significant from the i-butanol blend. The 12% i-butanol/7% ethanol blend was designed to produce no increase in gasoline vapor pressure. This fuel's exhaust emissions contained the lowest total oxygenates among the alcohol blends and the lowest NMOG of all fuels tested.


Subject(s)
Alcohols/analysis , Gasoline/analysis , Vehicle Emissions/analysis , 1-Butanol/analysis , Air Pollutants/analysis , Confidence Intervals , Ethanol/analysis , Hydrocarbons/analysis , Vapor Pressure
15.
Environ Sci Technol ; 47(6): 2990-7, 2013 Mar 19.
Article in English | MEDLINE | ID: mdl-23398464

ABSTRACT

Nine flex-fuel vehicles meeting Tier 1, light duty vehicle-low emission vehicle (LDV-LEV), light duty truck 2-LEV (LDT2-LEV), and Tier 2 emission standards were tested over hot-start and cold-start three-phase LA92 cycles for nonmethane organic gases, ethanol, acetaldehyde, formaldehyde, acetone, nitrous oxide, nitrogen oxides (NO(x)), carbon monoxide (CO), and carbon dioxide (CO(2)), as well as fuel economy. Emissions were measured immediately after refueling with E40. The vehicles had previously been adapted to either E10 or E76. An overall comparison of emissions and fuel economy behavior of vehicles running on E40 showed results generally consistent with adaptation to the blend after the length of the three-phase hot-start LA92 test procedure (1735 s, 11 miles). However, the single LDT2-LEV vehicle, a Dodge Caravan, continued to exhibit statistically significant differences in emissions for most pollutants when tested on E40 depending on whether the vehicle had been previously adapted to E10 or E76. The results were consistent with an overestimate of the amount of ethanol in the fuel when E40 was added immediately after the use of E76. Increasing ethanol concentration in fuel led to reductions in fuel economy, NO(x), CO, CO(2), and acetone emissions as well as increases in emissions of ethanol, acetaldehyde, and formaldehyde.


Subject(s)
Ethanol/analysis , Gasoline/analysis , Vehicle Emissions/analysis , Acetaldehyde/analysis , Acetone/analysis , Air Pollutants/analysis , Carbon Dioxide/analysis , Carbon Monoxide/analysis , Formaldehyde/analysis , Motor Vehicles/standards , Nitrogen Oxides/analysis
16.
BMJ Case Rep ; 20112011 May 03.
Article in English | MEDLINE | ID: mdl-22696694

ABSTRACT

This study illustrates the case of a middle-aged woman who presented with sepsis and purpura fulminans, found to be due to Streptococcus pneumoniae infection. She later developed blindness from a dramatic ocular inflammatory response provoked by pneumococcal antigens.


Subject(s)
Blindness/etiology , Pneumococcal Infections/complications , Sepsis/complications , Uveitis/etiology , Anti-Bacterial Agents/therapeutic use , Female , Humans , Magnetic Resonance Imaging , Middle Aged , Pneumococcal Infections/drug therapy , Purpura Fulminans/complications , Purpura Fulminans/diagnosis , Purpura Fulminans/microbiology , Sepsis/drug therapy , Sepsis/microbiology , Uveitis/drug therapy
17.
Environ Sci Technol ; 44(21): 8343-9, 2010 Nov 01.
Article in English | MEDLINE | ID: mdl-20886845

ABSTRACT

The impacts of biodiesel and a continuously regenerated (catalyzed) diesel particle filter (DPF) on the emissions of volatile unburned hydrocarbons, carbonyls, and particle associated polycyclic aromatic hydrocarbons (PAH) and nitro-PAH, were investigated. Experiments were conducted on a 5.9 L Cummins ISB, heavy-duty diesel engine using certification ultra-low-sulfur diesel (ULSD, S ≤ 15 ppm), soy biodiesel (B100), and a 20% blend thereof (B20). Against the ULSD baseline, B20 and B100 reduced engine-out emissions of measured unburned volatile hydrocarbons and PM associated PAH and nitro-PAH by significant percentages (40% or more for B20 and higher percentage for B100). However, emissions of benzene were unaffected by the presence of biodiesel and emissions of naphthalene actually increased for B100. This suggests that the unsaturated FAME in soy-biodiesel can react to form aromatic rings in the diesel combustion environment. Methyl acrylate and methyl 3-butanoate were observed as significant species in the exhaust for B20 and B100 and may serve as markers of the presence of biodiesel in the fuel. The DPF was highly effective at converting gaseous hydrocarbons and PM associated PAH and total nitro-PAH. However, conversion of 1-nitropyrene by the DPF was less than 50% for all fuels. Blending of biodiesel caused a slight reduction in engine-out emissions of acrolein, but otherwise had little effect on carbonyl emissions. The DPF was highly effective for conversion of carbonyls, with the exception of formaldehyde. Formaldehyde emissions were increased by the DPF for ULSD and B20.


Subject(s)
Air Pollutants/analysis , Air Pollution/prevention & control , Filtration , Vehicle Emissions/prevention & control , Aldehydes/analysis , Biofuels , Hydrocarbons/analysis , Ketones/analysis , Particulate Matter/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Pyrenes/analysis , Vehicle Emissions/analysis
18.
Exp Brain Res ; 205(2): 273-82, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20652230

ABSTRACT

Traditional approaches to research on bimanual coordination focus on sensorimotor interference, motor programming, and effects of perception and feedback guidance; surprisingly, little is known about high-level conceptual constraints that might unify separate movements into coordinated actions. We investigated two possible forms of high-level unifying representations on anticipatory control (i.e., reaction time: RT) in two-limb (bimanual) movements. Specifically, we adapted a paradigmatic bimanual task involving reaching to targets by adding two novel manipulations. One involved a visual-perceptual manipulation in which target-objects were presented either separately (i.e., two circles) or as a unified object (i.e., two circles connected by a bar). The other involved variants on language representation to elicit separate action plans (i.e., separate instructional commands joined by 'and') or unified action plans (i.e., a single verb applying to both hands). Typical forms of sensorimotor interference were virtually abolished when these unifying constraints were available. These findings provide strong support for the theoretical account that unifying conceptual representations are primary forms of bimanual constraint. Findings further suggest that the organization and content of the language used to form action representations can strongly influence anticipatory planning of bimanual actions.


Subject(s)
Functional Laterality/physiology , Motor Skills/physiology , Visual Perception/physiology , Adolescent , Cognition/physiology , Female , Humans , Language , Male , Movement/physiology , Photic Stimulation , Psychomotor Performance , Reaction Time/physiology , Young Adult
19.
Curr Top Microbiol Immunol ; 345: 47-70, 2010.
Article in English | MEDLINE | ID: mdl-20549470

ABSTRACT

The molecular response of cancer cells to hypoxia is the focus of intense research. In the last decade, research into microRNAs (miRNAs), small RNAs which have a role in regulation of mRNA and translation, has grown exponentially. miR-210 has emerged as the predominant miRNA regulated by hypoxia. Elucidation of its targets points to a variety of roles for this, and other hypoxia-regulated miRNAs (HRMs), in tumour growth and survival. miR-210 expression correlates with poor survival in cancer patients, and shows promise for future use as a tumour marker or therapeutic agent. The role of miR-210 and other HRMs in cancer biology is the subject of this review.


Subject(s)
Cell Hypoxia , MicroRNAs/physiology , Neoplasms/etiology , Humans , Iron-Sulfur Proteins/metabolism , Mitochondria/metabolism , Neoplasms/genetics , Neoplasms/metabolism , Protein Biosynthesis , RNA, Messenger/metabolism
20.
PLoS One ; 5(4): e10345, 2010 Apr 26.
Article in English | MEDLINE | ID: mdl-20436681

ABSTRACT

BACKGROUND: Hypoxia in cancers results in the upregulation of hypoxia inducible factor 1 (HIF-1) and a microRNA, hsa-miR-210 (miR-210) which is associated with a poor prognosis. METHODS AND FINDINGS: In human cancer cell lines and tumours, we found that miR-210 targets the mitochondrial iron sulfur scaffold protein ISCU, required for assembly of iron-sulfur clusters, cofactors for key enzymes involved in the Krebs cycle, electron transport, and iron metabolism. Down regulation of ISCU was the major cause of induction of reactive oxygen species (ROS) in hypoxia. ISCU suppression reduced mitochondrial complex 1 activity and aconitase activity, caused a shift to glycolysis in normoxia and enhanced cell survival. Cancers with low ISCU had a worse prognosis. CONCLUSIONS: Induction of these major hallmarks of cancer show that a single microRNA, miR-210, mediates a new mechanism of adaptation to hypoxia, by regulating mitochondrial function via iron-sulfur cluster metabolism and free radical generation.


Subject(s)
Citric Acid Cycle , Free Radicals/metabolism , Hypoxia , Iron-Sulfur Proteins/metabolism , MicroRNAs/physiology , Mitochondria/metabolism , Neoplasms/metabolism , Cell Line, Tumor , Electron Transport Complex I/metabolism , Humans , Hypoxia-Inducible Factor 1, alpha Subunit , Neoplasms/pathology , Prognosis
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