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1.
medRxiv ; 2023 Feb 16.
Article in English | MEDLINE | ID: mdl-36824731

ABSTRACT

It has been estimated that 15%-20% of human cancers are attributable to infections, mostly by carcinogenic viruses. The incidence varies worldwide, with a majority affecting developing countries. Here, we present a comparative analysis of virus-positive and virus-negative tumors in nine cancers linked to five viruses. We find that virus-positive tumors occur more frequently in males and show geographical disparities in incidence. Genomic analysis of 1,658 tumors reveals virus-positive tumors exhibit distinct mutation signatures and driver gene mutations and possess a lower somatic mutation burden compared to virus-negative tumors of the same cancer type. For example, compared to the respective virus-negative counterparts, virus-positive cases across different cancer histologies had less often mutations of TP53 and deletions of 9p21.3/ CDKN2 A- CDKN1A ; Epstein-Barr virus-positive (EBV+) gastric cancer had more frequent mutations of EIF4A1 and ARID1A and less marked mismatch repair deficiency signatures; and EBV-positive cHL had fewer somatic genetic lesions of JAK-STAT, NF-κB, PI3K-AKT and HLA-I genes and a less pronounced activity of the aberrant somatic hypermutation signature. In cHL, we also identify germline homozygosity in HLA class I as a potential risk factor for the development of EBV-positive Hodgkin lymphoma. Finally, an analysis of clinical trials of PD-(L)1 inhibitors in four virus-associated cancers suggested an association of viral infection with higher response rate in patients receiving such treatments, which was particularly evident in gastric cancer and head and neck squamous cell carcinoma. These results illustrate the epidemiological, genetic, prognostic, and therapeutic trends across virus-associated malignancies.

2.
Appl Microbiol Biotechnol ; 106(4): 1715-1727, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35089401

ABSTRACT

Estuarine sediments near former creosoting facilities along the Elizabeth River (Virginia, USA) are contaminated by polycyclic aromatic hydrocarbons (PAHs). In this study, we interrogated the bacterial community of the Elizabeth River with both culture-based and culture-independent methods to identify potential candidates for bioremediation of these contaminants. DNA-based stable isotope probing (SIP) experiments with phenanthrene and fluoranthene using sediment from the former Republic Creosoting site identified relevant PAH-degrading bacteria within the Azoarcus, Hydrogenophaga, and Croceicoccus genera. Targeted cultivation of PAH-degrading bacteria from the same site recovered 6 PAH-degrading strains, including one strain highly similar to Hydrogenophaga sequences detected in SIP experiments. Other isolates were most similar to organisms within the Novosphingobium, Sphingobium, Stenotrophomonas, and Alcaligenes genera. Lastly, we performed 16S rRNA gene amplicon microbiome analyses of sediment samples from four sites, including Republic Creosoting, with varying concentrations of PAHs. Analysis of these data showed a striking divergence of the microbial community at the highly contaminated Republic Creosoting site from less contaminated sites with the enrichment of several bacterial clades including those affiliated with the Pseudomonas genus. Sequences within the microbiome libraries similar to SIP-derived sequences were generally found at high relative abundance, while the Croceicoccus sequence was present at low to moderate relative abundance. These results suggest that Azoarcus and Hydrogenophaga strains might be good target candidates for biostimulation, while Croceicoccus spp. might be good targets for bioaugmentation in these sediments. Furthermore, this study demonstrates the value of culture-based and culture-independent methods in identifying promising bacterial candidates for use in a precision bioremediation scheme. KEY POINTS: • This study highlights the importance of using multiple strategies to identify promising bacterial candidates for use in a precision bioremediation scheme. • We used both selective cultivation techniques and DNA-based stable isotope probing to identify bacterial degraders of prominent PAHs at a historically contaminated site in the Elizabeth River, VA, USA. • Azoarcus and Hydrogenophaga strains might be good target candidates for biostimulation in Elizabeth River sediments, while Croceicoccus spp. might be good targets for bioaugmentation.


Subject(s)
Polycyclic Aromatic Hydrocarbons , Soil Pollutants , Bacteria/genetics , Biodegradation, Environmental , Geologic Sediments , RNA, Ribosomal, 16S/genetics , Rivers , Soil Pollutants/analysis
3.
Emerg Med Australas ; 33(2): 270-278, 2021 04.
Article in English | MEDLINE | ID: mdl-32929847

ABSTRACT

OBJECTIVE: ED avoidance strategies including In-Event Health Service (IEHS) processes during mass gathering events (MGEs), such as 'Schoolies week', may be important for EDs, ambulance services, the local population, and attendees. The aim of the present study was to provide a longitudinal description of emergency care requirements for young adults (16-18 years old); focussing on the impact of the Schoolies MGEs. METHODS: This retrospective observational study included youth (16-18 years) presentations made (i) to local public EDs during Schoolies week in 2008-2014 and (ii) to local EDs over a 3-week period (pre, during, post-Schoolies week) and the IEHS in 2015 and 2016. Descriptive and inferential statistics were undertaken. RESULTS: Youth presentations (n = 4256) were included. Presentation rates/1000 fluctuated over time (range 6.2-21.2). The IEHS provided care for 167 and 288 youth during 2015 and 2016 Schoolies week, respectively. Demographic factors (gender, age, region domiciled) and episode of care factors (time of presentation, mode of arrival, urgency, time to triage, time to be seen by a clinician and length of stay) between 2008 and 2016 varied by year. Toxicology (alcohol and other drugs), trauma, and mental health concerns were the most common diagnoses. CONCLUSIONS: The IEHS, operational during Schoolies, appeared to reduce pressures on local EDs by offering rapid, targeted care for potentially vulnerable youth; decrease requirements for hospital transport and minimise impacts on care provision for the local community. Given increases in ED crowding and pressures on ambulance services, such care models may be worth considering for other types of MGEs and in other locations.


Subject(s)
Crowding , Emergency Medical Services , Adolescent , Ambulances , Australia , Emergency Service, Hospital , Humans , Young Adult
4.
Materials (Basel) ; 13(12)2020 Jun 15.
Article in English | MEDLINE | ID: mdl-32549187

ABSTRACT

The potential release of hazardous substances from polymer-based products is currently in the focus of environmental policy. Environmental simulations are applied to expose such products to selected aging conditions and to investigate release processes. Commonly applied aging exposure types such as solar and UV radiation in combination with water contact, corrosive gases, and soil contact as well as expected general effects on polymers and additional ingredients of polymer-based products are described. The release of substances is based on mass-transfer processes to the material surfaces. Experimental approaches to investigate transport processes that are caused by water contact are presented. For tailoring the tests, relevant aging exposure types and release quantification methods must be combined appropriately. Several studies on the release of hazardous substances such as metals, polyaromatic hydrocarbons, flame retardants, antioxidants, and carbon nanotubes from polymers are summarized exemplarily. Differences between natural and artificial exposure tests are discussed and demonstrated for the release of flame retardants from several polymers and for biocides from paints. Requirements and limitations to apply results from short-term artificial environmental exposure tests to predict long-term environmental behavior of polymers are presented.

5.
Appl Microbiol Biotechnol ; 104(3): 1063-1076, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31813048

ABSTRACT

During screening for novel emulsifiers and surfactants, a marine gammaproteobacterium, Halomonas sp. MCTG39a, was isolated and selected for its production of an extracellular emulsifying agent, P39a. This polymer was produced by the new isolate during growth in a modified Zobell's 2216 medium amended with 1% glucose, and was extractable by cold ethanol precipitation. Chemical, chromatographic and nuclear magnetic resonance spectroscopic analysis confirmed P39a to be a high-molecular-weight (~ 261,000 g/mol) glycoprotein composed of carbohydrate (17.2%) and protein (36.4%). The polymer exhibited high emulsifying activities against a range of oil substrates that included straight-chain aliphatics, mono- and alkyl- aromatics and cycloparaffins. In general, higher emulsification values were measured under low (0.1 M PBS) compared to high (synthetic seawater) ionic strength conditions, indicating that low ionic strength is more favourable for emulsification by the P39a polymer. However, as observed with other bacterial emulsifying agents, the polymer emulsified some aromatic hydrocarbon species, as well as refined and crude oils, more effectively under high ionic strength conditions, which we posit could be due to steric adsorption to these substrates as may be conferred by the protein fraction of the polymer. Furthermore, the polymer effected a positive influence on the degradation of phenanthrene by other marine bacteria, such as the specialist PAH-degrader Polycyclovorans algicola. Collectively, based on the ability of this Halomonas high-molecular-weight glycoprotein to emulsify a range of pure hydrocarbon species, as well as refined and crude oils, it shows promise for the bioremediation of contaminated sites.


Subject(s)
Emulsifying Agents/chemistry , Extracellular Polymeric Substance Matrix/chemistry , Halomonas/chemistry , Biodegradation, Environmental , Phylogeny , RNA, Ribosomal, 16S , Seawater/microbiology , Surface-Active Agents/chemistry
6.
Emerg Med Australas ; 32(2): 250-257, 2020 04.
Article in English | MEDLINE | ID: mdl-31711276

ABSTRACT

OBJECTIVE: To describe patient presentation characteristics and outcomes for people aged 16-18 years pre, during and post a planned youth mass gathering event (MGE): 'Schoolies week' on the Gold Coast, Queensland, Australia. METHODS: This was a retrospective observational study, including patient presentations by all young adults requiring care in the ED or in-event health services (EHS) over a 21-day period in 2014. Data analysis included descriptive and inferential statistics. RESULTS: A total of 1029 patient presentations were made by people aged 16-18 years to the ED and EHS over the 21-day study period (139 pre, 695 during [275 in ED, 420 in EHS], 195 post Schoolies week). Some ED patient characteristics and outcomes varied between the pre, during and post Schoolies periods, such as patients age (P < 0.001), usual place of residence (P < 0.001) and not waiting for treatment (P = 0.015). Of the 24 375 registered MGE attendees, 420 (1.72% [95% confidence interval 1.57-1.89], 17.2/1000) presented for in-event care. Most patients were allocated an Australasian Triage Scale category of 4 (n = 162, 65.6%), with toxicology related presentations (n = 169, 44.9%). Transportation to hospital was undertaken for seven MGE attendees (0.03% [95% confidence interval 0.01-0.06], 0.3/1000). CONCLUSIONS: Establishment of an in-event model of care for 1 week during Schoolies served as an effective hospital avoidance strategy for a planned youth MGE. Such in-event models of care may be considered for other similar future MGE.


Subject(s)
Emergency Medical Services , Adolescent , Australia , Delivery of Health Care , Emergency Service, Hospital , Humans , Retrospective Studies , Young Adult
7.
Sci Total Environ ; 707: 135503, 2020 Mar 10.
Article in English | MEDLINE | ID: mdl-31780161

ABSTRACT

Polycyclic aromatic nitrogen heterocycles, or azaarenes, normally co-occur with polycyclic aromatic hydrocarbons (PAHs) in contaminated soils. We recently reported that nontarget analysis using high resolution mass spectrometry of samples from four PAH-contaminated sites revealed a previously unrecognized diversity and abundance of azaarene isomers and their methylated derivatives. Here we evaluated their biodegradability by natural microbial communities from each site in aerobic microcosm incubations under biostimulated conditions. The removal of total quantifiable azaarenes ranged from 15 to 85%, and was related to the initial degree of weathering for each sample. While three-ring azaarenes were readily biodegradable, the five-ring congeners were the most recalcitrant. Microbial-mediated removal of four-ring congeners varied for different isomers, which might be attributed to the position of the nitrogen atom that also influences the physicochemical properties of azaarenes and possibly the susceptibility to transformation by relevant microbial enzymes. The presence of methyl groups also influenced azaarene biodegradability, which decreased with increasing degree of methylation. Several oxidation products of azaarenes were detected, including ketones and dioxygenated derivatives of three- and four-ring compounds. Our results indicate the susceptibility of some azaarenes to bioremediation, while suggesting the potential implications for risk from the persistence of less-biodegradable isomers and the formation of oxidized-azaarene derivatives.


Subject(s)
Biodegradation, Environmental , Polycyclic Aromatic Hydrocarbons , Soil Microbiology , Soil Pollutants
8.
Prehosp Disaster Med ; 34(1): 62-71, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30614427

ABSTRACT

INTRODUCTION: Mass gatherings such as marathons are increasingly frequent. During mass gatherings, the provision of timely access to health care services is required for the mass-gathering population, as well as for the local community. However, the nature and impact of health care provision during sporting mass gatherings is not well-understood. PURPOSE: The aim of this study was to describe the structures and processes developed for an emergency health team to operate an in-event, acute health care facility during one of the largest mass-sporting participation events in the southern hemisphere, the Gold Coast Marathon (Queensland, Australia). METHODS: A pragmatic, qualitative methodology was used to describe the structures and processes required to operate an in-event, acute health care facility providing services for marathon runners and spectators. Content analysis from 12 semi-structured interviews with emergency department (ED) clinical staff working during the two-day event was undertaken in 2016. FINDINGS: Important structural elements of the in-event health care facility included: physical spaces, such as the clinical zones in the marathon health tent and surrounding area, and access and egress points; and resources such as bilingual staff, senior medical staff, and equipment such as electrocardiograms (ECGs) and intravenous fluids. Process elements of the in-event health care facility included clear communication pathways, as well as inter-professional care coordination and engagement involving shared knowledge of and access to resources, and distinct but overlapping clinical scope between nurses and doctors. This was seen to be critical for timely care provision and appropriate case management. Staff reported many perceived benefits and opportunities of in-event health care delivery, including ED avoidance and disaster training. CONCLUSIONS: This in-event model of emergency care delivery, established in an out-of-hospital location, enabled the delivery of acute health care that could be clearly described and defined. Staff reported satisfaction with their ability to provide a meaningful contribution to hospital avoidance and to the local community. With the number of sporting mass gatherings increasing, this temporary, in-event model of health care provision is one option for event and health care planners to consider.JohnstonANB, WadhamJ, Polong-BrownJ, AitkenM, RanseJ, HuttonA, RichardsB, CrillyJ.Health care provision during a sporting mass gathering: a structure and process description of on-site care delivery. Prehosp Disaster Med. 2019;34(1):62-71.

9.
Q J Exp Psychol (Hove) ; 72(2): 311-321, 2019 Feb.
Article in English | MEDLINE | ID: mdl-27894212

ABSTRACT

Associative learning theories regard the probability of reinforcement as the critical factor determining responding. However, the role of this factor in instrumental conditioning is not completely clear. In fact, free-operant experiments show that participants respond at a higher rate on variable ratio than on variable interval schedules even though the reinforcement probability is matched between the schedules. This difference has been attributed to the differential reinforcement of long inter-response times (IRTs) by interval schedules, which acts to slow responding. In the present study, we used a novel experimental design to investigate human responding under random ratio (RR) and regulated probability interval (RPI) schedules, a type of interval schedule that sets a reinforcement probability independently of the IRT duration. Participants responded on each type of schedule before a final choice test in which they distributed responding between two schedules similar to those experienced during training. Although response rates did not differ during training, the participants responded at a lower rate on the RPI schedule than on the matched RR schedule during the choice test. This preference cannot be attributed to a higher probability of reinforcement for long IRTs and questions the idea that similar associative processes underlie classical and instrumental conditioning.


Subject(s)
Association Learning/physiology , Conditioning, Operant/physiology , Female , Humans , Male , Probability , Reaction Time/physiology , Reinforcement, Psychology , Students , Universities
10.
Learn Motiv ; 64: 1-8, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30532341

ABSTRACT

The higher response rates observed on ratio than on matched interval reward schedules has been attributed to the differential reinforcement of longer inter-response times (IRTs) on the interval contingency. Some data, however, seem to contradict this hypothesis, showing that the difference is still observed when the role of IRT reinforcement is neutralized by using a regulated-probability interval schedule (RPI). Given the mixed evidence for these predictions, we re-examined this hypothesis by training three groups of rats to lever press under ratio, interval and RPI schedules across two phases while matching reward rates within triads. At the end of the first phase, the master ratio and RPI groups responded at similar rates. In the second phase, an interval group yoked to the same master ratio group of the first phase responded at a lower rate than the RPI group. Post-hoc analysis showed comparable reward rates for master and yoked schedules. The experienced response-outcome rate correlations were likewise similar and approached zero as training progressed. We discuss these results in terms of a contemporary dual-system model of instrumental conditioning.

11.
Syst Appl Microbiol ; 41(5): 460-472, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29937052

ABSTRACT

Four bacterial strains identified as members of the Acidovorax genus were isolated from two geographically distinct but similarly contaminated soils in North Carolina, USA, characterized, and their genomes sequenced. Their 16S rRNA genes were highly similar to those previously recovered during stable-isotope probing (SIP) of one of the soils with the polycyclic aromatic hydrocarbon (PAH) phenanthrene. Heterotrophic growth of all strains occurred with a number of organic acids, as well as phenanthrene, but no other tested PAHs. Optimal growth occurred aerobically under mesophilic temperature, neutral pH, and low salinity conditions. Predominant fatty acids were C16:1ω7c/C16:1ω6c, C16:0, and C18:1ω7c, and were consistent with the genus. Genomic G+C contents ranged from 63.6 to 64.2%. A combination of whole genome comparisons and physiological analyses indicated that these four strains likely represent a single species within the Acidovorax genus. Chromosomal genes for phenanthrene degradation to phthalate were nearly identical to highly conserved regions in phenanthrene-degrading Delftia, Burkholderia, Alcaligenes, and Massilia species in regions flanked by transposable or extrachromosomal elements. The lower degradation pathway for phenanthrene metabolism was inferred by comparisons to described genes and proteins. The novel species Acidovorax carolinensis sp. nov. is proposed, comprising the four strains described in this study with strain NA3T as the type strain (=LMG 30136, =DSM 105008).


Subject(s)
Comamonadaceae/classification , Comamonadaceae/physiology , Phenanthrenes/metabolism , Phylogeny , Soil Microbiology , Biodegradation, Environmental , Comamonadaceae/chemistry , Comamonadaceae/genetics , DNA, Bacterial , Genes, Bacterial , Genome, Bacterial/genetics , Metabolic Networks and Pathways/genetics , North Carolina , RNA, Ribosomal, 16S , Sequence Analysis, DNA , Soil Pollutants/metabolism
12.
Environ Sci Technol Lett ; 5(2): 103-109, 2018 Feb 13.
Article in English | MEDLINE | ID: mdl-31572742

ABSTRACT

Biotransformation of organic pollutants may result in the formation of oxidation products more toxic than the parent contaminants. However, to trace and identify those products, and the metabolic pathways involved in their formation, is still challenging within complex environmental samples. We applied stable isotope-assisted metabolomics (SIAM) to PAH-contaminated soil collected from a wood treatment facility. Soil samples were separately spiked with uniformly 13C-labeled fluoranthene, pyrene, or benzo[a]anthracene at a level below that of the native contaminant, and incubated for 1 or 2 weeks under aerobic biostimulated conditions. Combining high-resolution mass spectrometry and automated SIAM workflows, chemical structures of metabolites and metabolic pathways in the soil were proposed. Ring-cleavage products, including previously unreported intermediates such as C11H10O6 and C15H12O5, were detected originating from fluoranthene and benzo[a]anthracene, respectively. Sulfate conjugates of dihydroxy compounds were found as major metabolites of pyrene and benzo[a]anthracene, suggesting the potential role of fungi in their biotransformation in soils. A series of unknown N-containing metabolites were identified from pyrene, but their structural elucidation requires further investigation. Our results suggest that SIAM can be successfully applied to understand the fate of organic pollutants in environmental samples, opening lines of evidence for novel mechanisms of microbial transformation within such complex matrices.

14.
Environ Sci Technol ; 51(24): 14047-14054, 2017 Dec 19.
Article in English | MEDLINE | ID: mdl-29160699

ABSTRACT

Azaarenes are N-heterocyclic polyaromatic pollutants that co-occur with polycyclic aromatic hydrocarbons (PAHs) in contaminated soils. Despite the known toxicity of some high-molecular-weight azaarenes, their diversity, abundance, and fate in contaminated soils remain to be elucidated. We applied high-resolution mass spectrometry and mass-defect filtering to four PAH-contaminated samples from geographically distant sites and detected 232 azaarene congeners distributed in eight homologous series, including alkylated derivatives and two hitherto unknown series. Four- and five-ring azaarenes were detected among these series, and the most abundant nonalkylated congeners groups (C13H9N, C15H9N, C17H11N, C19H11N, and C21H13N) were quantified. The profiles of congener groups varied among different sites. Three-ring azaarenes presented higher concentrations in unweathered sites, while four- and five-ring azaarenes predominated in weathered sites. Known toxic and carcinogenic azaarenes, such as benzo[c]acridine and dibenzo[a,h]acridine, were detected along with their multiple isomers. Our results highlight a previously unrecognized diversity and abundance of azaarenes in PAH-contaminated sites, with corresponding implications for environmental monitoring and risk assessment.


Subject(s)
Environmental Monitoring , Polycyclic Aromatic Hydrocarbons , Risk Assessment
15.
J Behav Decis Mak ; 30(4): 855-868, 2017 10.
Article in English | MEDLINE | ID: mdl-29081596

ABSTRACT

Research on gambling near-misses has shown that objectively equivalent outcomes can yield divergent emotional and motivational responses. The subjective processing of gambling outcomes is affected substantially by close but non-obtained outcomes (i.e. counterfactuals). In the current paper, we investigate how different types of near-misses influence self-perceived luck and subsequent betting behavior in a wheel-of-fortune task. We investigate the counterfactual mechanism of these effects by testing the relationship with a second task measuring regret/relief processing. Across two experiments (Experiment 1, n = 51; Experiment 2, n = 104), we demonstrate that near-wins (neutral outcomes that are close to a jackpot) decreased self-perceived luck, whereas near-losses (neutral outcomes that are close to a major penalty) increased luck ratings. The effects of near-misses varied by near-miss position (i.e. whether the spinner stopped just short of, or passed through, the counterfactual outcome), consistent with established distinctions between upward versus downward, and additive versus subtractive, counterfactual thinking. In Experiment 1, individuals who showed stronger counterfactual processing on the regret/relief task were more responsive to near-wins and near-losses on the wheel-of-fortune task. The effect of near-miss position was attenuated when the anticipatory phase (i.e. the spin and deceleration) was removed in Experiment 2. Further differences were observed within the objective gains and losses, between "clear" and "narrow" outcomes. Taken together, these results help substantiate the counterfactual mechanism of near-misses.

16.
Rev Sci Instrum ; 88(6): 064502, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28667997

ABSTRACT

We report on the design and sensitivity of a new torsion pendulum for measuring the performance of ultra-precise inertial sensors and for the development of associated technologies for space-based gravitational wave observatories and geodesy missions. The apparatus comprises a 1 m-long, 50 µm-diameter tungsten fiber that supports an inertial member inside a vacuum system. The inertial member is an aluminum crossbar with four hollow cubic test masses at each end. This structure converts the rotation of the torsion pendulum into translation of the test masses. Two test masses are enclosed in capacitive sensors which provide readout and actuation. These test masses are electrically insulated from the rest of the crossbar and their electrical charge is controlled by photoemission using fiber-coupled ultraviolet light emitting diodes. The capacitive readout measures the test mass displacement with a broadband sensitivity of 30 nm∕Hz and is complemented by a laser interferometer with a sensitivity of about 0.5 nm∕Hz. The performance of the pendulum, as determined by the measured residual torque noise and expressed in terms of equivalent force acting on a single test mass, is roughly 200 fN∕Hz around 2 mHz, which is about a factor of 20 above the thermal noise limit of the fiber.

17.
Environ Sci Technol ; 51(12): 7091-7100, 2017 Jun 20.
Article in English | MEDLINE | ID: mdl-28510420

ABSTRACT

Bioremediation is an accepted technology for cleanup of soil contaminated with polycyclic aromatic hydrocarbons (PAHs), but it can increase the genotoxicity of the soil despite removal of the regulated PAHs. Although polar biotransformation products have been implicated as causative genotoxic agents, no specific product has been identified. We pursued a nontarget analytical approach combining effect-directed analysis (EDA) and metabolite profiling to compare extracts of PAH-contaminated soil from a former manufactured-gas plant site before and after treatment in a laboratory-scale aerobic bioreactor. A compound with the composition C15H8O2 and four methylated homologues were shown to accumulate as a result of bioreactor treatment, and the C15H8O2 compound purified from soil extracts was determined to be genotoxic. Its structure was established by nuclear magnetic resonance and mass spectroscopy as a heretofore unidentified α,ß-unsaturated lactone derived from dioxygenation of pyrene at an apical ring, 2H-naphtho[2,1,8-def]chromen-2-one (NCO), which was confirmed by synthesis. The concentration of NCO in the bioreactor was 11 µg g-1 dry soil, corresponding to 13% of the pyrene removed. It also accumulated in aerobically incubated soil from two additional PAH-contaminated sites and was formed from pyrene by two pyrene-degrading bacterial cultures known to be geographically widespread, underscoring its potential environmental significance.


Subject(s)
Biodegradation, Environmental , Pyrenes , Soil Pollutants , Polycyclic Aromatic Hydrocarbons , Soil , Soil Microbiology
18.
Sci Total Environ ; 599-600: 1099-1107, 2017 Dec 01.
Article in English | MEDLINE | ID: mdl-28511355

ABSTRACT

Bioremediation is a technique commonly used to reduce the toxicity associated with polycyclic aromatic hydrocarbons (PAHs) in contaminated soils. However, the efficacy of bioremedial applications is evaluated based on the removal of a subset of parent (or unsubstituted) PAHs and does not incorporate toxic polar transformation products or the more mutagenic high molecular weight PAHs (MW≥302amu or MW302-PAHs). Previously, an effects-directed analysis approach was used to assess the effect of bioremediation on the toxicity of a coal tar-contaminated soil. Increased genotoxicity and developmental toxicity was measured postbioremedation in the more polar soil extract fractions, as compared to the less polar fractions where the targeted PAHs eluted, and could not be attributed to the 88 target PAHs analyzed for (including selected oxygen-containing PAHs). In this study, comprehensive two-dimensional gas chromatography time-of-flight and liquid chromatography quadrupole time-of-flight mass spectrometry were used to characterize transformation products in the soil extract fractions identified as toxic, previously. Additionally, the degradation of 12MW302-PAHs, picene (MW=278) and coronene (MW=300) were evaluated following bioremediation. Non-targeted analysis resulted in the tentative identification of 10 peaks with increased intensity postbioremediation (based on mass spectral library matching and fragmentation patterns from >5000 candidate peaks in the soil extracts). Several of these compounds contained oxygen, suggesting they would be relatively polar. MW302-PAHs were not significantly degraded during bioremediation, suggesting that the carcinogenic potential associated with these PAHs might remain unchanged. The results of this study suggest that polar transformation products, and MW302-PAHs, should be considered for realistic risk assessment of bioremediated soils.

19.
Q J Exp Psychol (Hove) ; 70(8): 1732-1746, 2017 Aug.
Article in English | MEDLINE | ID: mdl-27376771

ABSTRACT

Illusory control refers to an effect in games of chance where features associated with skilful situations increase expectancies of success. Past work has operationalized illusory control in terms of subjective ratings or behaviour, with limited consideration of the relationship between these definitions, or the broader construct of agency. This study used a novel card-guessing task in 78 participants to investigate the relationship between subjective and behavioural illusory control. We compared trials in which participants (a) had no opportunity to exercise illusory control, (b) could exercise illusory control for free, or (c) could pay to exercise illusory control. Contingency Judgment and Intentional Binding tasks assessed explicit and implicit sense of agency, respectively. On the card-guessing task, confidence was higher when participants exerted control than in the baseline condition. In a complementary model, participants were more likely to exercise control when their confidence was high, and this effect was accentuated in the pay condition relative to the free condition. Decisions to pay were positively correlated with control ratings on the Contingency Judgment task, but were not significantly related to Intentional Binding. These results establish an association between subjective and behavioural illusory control and locate the construct within the cognitive literature on agency.


Subject(s)
Choice Behavior/physiology , Internal-External Control , Judgment , Psychomotor Performance/physiology , Adolescent , Female , Humans , Individuality , Intention , Male , Models, Psychological , Statistics as Topic , Surveys and Questionnaires , Young Adult
20.
Int J Syst Evol Microbiol ; 67(4): 925-931, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27926817

ABSTRACT

The bacterial strain TR3.2T was isolated from aerobic bioreactor-treated soil from a polycyclic aromatic hydrocarbon (PAH)-contaminated site in Salisbury, NC, USA. Strain TR3.2T was identified as a member of 'Pyrene Group 2' or 'PG2', a previously uncultivated cluster of organisms associated with the degradation of high-molecular-weight PAHs by stable-isotope probing. Based on its 16S rRNA gene sequence, the strain was classified as a member of the class Gammaproteobacteria but possessed only 90.5 % gene identity to its closest described relative, Methylococcus capsulatus strain Bath. Strain TR3.2T grew on the PAHs pyrene, phenanthrene, anthracene, benz[a]anthracene and fluorene, as well as the azaarene carbazole, and could additionally metabolize a limited number of organic acids. Optimal growth occurred aerobically under mesophilic temperature, neutral pH and low salinity conditions. Strain TR3.2T was catalase and oxidase positive. Predominant fatty acids were C17 : 0 cyclo and C16 : 0. Genomic G+C content of the single chromosome was 67.79 mol% as determined by complete genome sequencing. Due to the high sequence divergence from any cultivated species and its unique physiological properties compared to its closest relatives, strain TR3.2T is proposed as a representative of a novel order, family, genus and species within the class Gammaproteobacteria, for which the name Immundisolibacter cernigliae gen. nov., sp. nov. is proposed. The associated order and family are therefore proposed as Immundisolibacteralesord. nov. and Immundisolibacteraceaefam. nov. The type strain of the species is TR3.2T (=ATCC TSD-58T=DSM 103040T).


Subject(s)
Gammaproteobacteria/classification , Phylogeny , Polycyclic Aromatic Hydrocarbons/metabolism , Soil Microbiology , Bacterial Typing Techniques , Base Composition , Bioreactors/microbiology , DNA, Bacterial/genetics , Fatty Acids/chemistry , Gammaproteobacteria/genetics , Gammaproteobacteria/isolation & purification , North Carolina , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
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