Publications by authors named "David L Burton"

This study investigated the influence of biosolid applications on soil carbon storage and evaluated nutrient management strategies affecting soil carbon dynamics. The research assessed alterations in soil pH, soil carbon stock, and soil nitrogen content within short-term and long-term biosolids-amended soils in Bible Hill, Nova Scotia, Canada, extending to a depth of 0-60 cm. The findings indicated an increase in soil pH with alkaline treatment biosolids (ATB) applications across both study sites, with a legacy effect on soil pH noted in the long-term biosolids-amended soil following a single ATB application over 13 years.

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Chemical fumigation and biofumigation are used to reduce soil-borne diseases in agricultural production systems; however, non-targeted soil microorganisms may also be affected. This study compared the effects of chemical fumigation, either used alone or combined with an organic amendment, and biofumigation on soil bacterial community diversity and composition under controlled conditions over 160 days. Treatments included: fumigation with chloropicrin (CP), fumigation with metam sodium used alone (MS) or combined with barley plant residues (MSBR); biofumigation with mustard plant residues; addition of barley plant residues; and untreated control.

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Composts can be efficient organic amendments in potato culture as they can supply carbon and nutrients to the soil. However, more information is required on the effects of composts on denitrification and nitrous oxide emissions (NO) and emission-producing denitrifying communities. The effects of three compost amendments (municipal source separated organic waste compost (SSOC), forestry waste mixed with poultry manure compost (FPMC), and forestry residues compost (FRC)) on fungal and bacterial denitrifying communities and activity was examined in an agricultural field cropped to potatoes during the fall, spring, and summer seasons.

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In eastern Canada, climate change-related warming and increased precipitation may alter winter snow cover, with potential consequences for soil conditions, nitrogen (N) cycling, and microbes. We conducted a 2-year field study aimed at determining the influence of snow removal, snow accumulation, and ambient snow in a potato-barley crop system on the abundance and expression of denitrifier (nirS, nirK, nosZ) and nitrifier (ammonium oxidizing archaeal (AOA) and bacterial (AOB) amoA) genes. Denitrifier and nitrifier abundance and expression results were compared to N2O production, soil atmosphere accumulation, and surface fluxes.

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Potato cultivars vary in their tolerance to common scab; however, how they affect common scab-causing Streptomyces spp. populations over time is poorly understood. This study investigated the effects of potato cultivar on pathogenic Streptomyces spp.

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Unlabelled: Denitrifying fungi produce nitrous oxide (N2O), a potent greenhouse gas, as they generally lack the ability to convert N2O to dinitrogen. Contrary to the case for bacterial denitrifiers, the prevalence and diversity of denitrifying fungi found in the environment are not well characterized. In this study, denitrifying fungi were isolated from various soil ecosystems, and novel PCR primers targeting the P450nor gene, encoding the enzyme responsible for the conversion of nitric oxide to N2O, were developed, validated, and used to study the diversity of cultivable fungal denitrifiers.

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Tillage effects on denitrifier communities and nitrous oxide (N2O) emissions were mainly studied during the growing season. There is limited information for the non-growing season, especially in northern countries where winter has prolonged periods with sub-zero temperatures. The abundance and structure of the denitrifier community, denitrification gene expression and N2O emissions in fields under long-term tillage regimes [no-tillage (NT) vs conventional tillage (CT)] were assessed during two consecutive winters.

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In this study, we explore nonsexual crimes committed by a sample of 437 incarcerated adolescent sexual offenders as well as deviant arousal and its relationships to nonsexual and sexual crimes. Over 50% of the juvenile sexual offenders in this sample have committed nonsexual offenses. In addition, nonsexual crimes, particularly general delinquency, were significantly correlated to a number of characteristics of sexual crimes committed by the youth.

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Researchers have indicated that adult psychopathy often originates in childhood or adolescence. It has also been established that psychopathic traits are linked to disruptive behavior, criminality, and violence. As knowledge about psychopathy and its manifestations in juvenile sex offender populations remains limited, several instruments have been developed in an effort to measure the construct.

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This pilot study explored the pre-arrest self-selected cessation attempts of sexual offenders (N = 109) who abused children and often others. Four participants were dropped because of invalid responding (N = 104). While 74.

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Climate warming in temperate regions may lead to decreased soil temperatures over winter as a result of reduced snow cover. We examined the effects of temperatures near the freezing point on N(2)O emissions, denitrification, and on the abundance and structure of soil nitrifiers and denitrifiers. Soil microcosms supplemented with NO3 - and/or NO3 - plus red clover residues were incubated for 120 days at -4 °C, -1 °C, +2 °C or +5 °C.

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In this project, the authors examined the relationship trait anxiety has on incarcerated male adolescents' progression from childhood exposure to violence/victimization to violent behavior. Self-report survey data were analyzed to determine the youth's levels of trait anxiety, how the degree of childhood trauma was related to their level of anxiety, as well as whether their level of anxiety affected the relationship between trauma and subsequent frequency and severity of their delinquent acts using a moderation analysis. Anxiety significantly decreased the relationship between victimization and the commission of violence (F = 15.

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In a recent paper published in the Journal of Child Sexual Abuse, we assessed the differences between sexually victimized and nonsexually victimized male adolescent sexual abusers ( Burton, Duty, & Leibowitz, 2011 ). We found that the sexually victimized group had more severe developmental antecedents (e.g.

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Article Synopsis
  • The study investigates the impact of glucose and nitrate additions on the nitrogen cycle in anoxic soils with Pseudomonas mandelii.
  • Adding glucose significantly boosts the gene expression and abundance of nitric oxide reductase (cnorB), while the effects of nitrate depend on glucose presence.
  • Cumulative denitrification rates were highest in soils with glucose and moderate nitrate levels, suggesting that carbon availability plays a critical role in denitrification processes.
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Article Synopsis
  • Different land management types (riparian vs. agricultural) significantly affect soil properties, water content, and nutrient levels, influencing denitrifier communities and nitrous oxide (N2O) emissions.
  • N2O emissions were higher in the agricultural zone, while complete denitrification to N2 was more prevalent in the riparian zone, and specific denitrifier gene expressions varied between the two areas.
  • The community structures of denitrifiers (specifically nirK and nirS genes) showed differing responses to environmental conditions, with nirK-gene-bearing communities being more sensitive to ecosystem changes than nirS-gene-bearing communities.
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An etiological model of sexually abusive behavior including dissociation could have utility for researchers and treatment providers working with sexually abusive youth with trauma histories. This article explores relationships between dissociation, victimization, and juvenile sexual offending. Self-reported data on dissociation and 5 types of abuse were collected from 2 racially/ethnically diverse groups of sexually abusive and general delinquent male adolescents (n = 502).

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Despite Burton and Meezan's (2004) finding that sexually aggressive youth are three to four times more likely to recidivate nonsexually than sexually, there is little to no research to date that explores this overlap in criminality. With a sample of 290 male sexually violent adjudicated and incarcerated youth, this study was able to successfully predict those who are exclusively sexually violent from those who are both nonsexually and sexually violent with each of the following factors: childhood trauma, masculine beliefs, and alcohol use. While alcohol use accounted for the greatest variance between the groups, masculine beliefs offered the greatest basis for the discussion and future projects for the authors of the study.

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In agricultural cropping systems, crop residues are sources of organic carbon (C), an important factor influencing denitrification. The effects of red clover, soybean, and barley plant residues and of glucose on denitrifier abundance, denitrification gene mRNA levels, nitrous oxide (N(2)O) emissions, and denitrification rates were quantified in anoxic soil microcosms for 72 h. nosZ gene abundances and mRNA levels significantly increased in response to all organic carbon treatments over time.

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Nitrate acts as an electron acceptor in the denitrification process. The effect of nitrate in the range of 0 to 1,000 mg/liter on Pseudomonas mandelii nirS, cnorB, and nosZ gene expression was studied, using quantitative reverse transcription-quantitative PCR. Denitrification activity was measured by using the acetylene blockage method and gas chromatography.

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Pseudomonas mandelii liquid cultures were studied to determine the effect of pH and temperature on denitrification gene expression, which was quantified by quantitative reverse transcription-PCR. Denitrification was measured by the accumulation of nitrous oxide (N(2)O) in the headspace in the presence of acetylene. Levels of gene expression of nirS and cnorB at pH 5 were 539-fold and 6,190-fold lower, respectively, than the levels of gene expression for cells grown at pH 6, 7, and 8 between 4 h and 8 h.

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Pure cultures of Pseudomonas mandelii were incubated with or without nitrate, which acts as a substrate and an electron acceptor for denitrification. Nitric oxide reductase (cnorB) gene expression was measured using a quantitative reverse transcription-PCR, and nitrous oxide emissions were measured by gas chromatography. P.

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This study measured total bacterial and denitrifier community abundances over time in an agricultural soil cropped to potatoes (Solanum tuberosum L.) by using quantitative PCR. Samples were collected on 10 dates from spring to autumn and from three spatial locations: in the potato "hill" between plants (H), close to the plant (H(p)), and in the "furrow" (F).

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