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1.
Environ Sci Technol ; 45(13): 5498-505, 2011 Jul 01.
Article in English | MEDLINE | ID: mdl-21627159

ABSTRACT

Alternative fuels and injection technologies are a necessary component of particulate emission reduction strategies for compression ignition engines. Consequently, this study undertakes a physicochemical characterization of diesel particulate matter (DPM) for engines equipped with alternative injection technologies (direct injection and common rail) and alternative fuels (ultra low sulfur diesel, a 20% biodiesel blend, and a synthetic diesel). Particle physical properties were addressed by measuring particle number size distributions, and particle chemical properties were addressed by measuring polycyclic aromatic hydrocarbons (PAHs) and reactive oxygen species (ROS). Particle volatility was determined by passing the polydisperse size distribution through a thermodenuder set to 300 °C. The results from this study, conducted over a four point test cycle, showed that both fuel type and injection technology have an impact on particle emissions, but injection technology was the more important factor. Significant particle number emission (54%-84%) reductions were achieved at half load operation (1% increase-43% decrease at full load) with the common rail injection system; however, the particles had a significantly higher PAH fraction (by a factor of 2 to 4) and ROS concentrations (by a factor of 6 to 16) both expressed on a test-cycle averaged basis. The results of this study have significant implications for the health effects of DPM emissions from both direct injection and common rail engines utilizing various alternative fuels.


Subject(s)
Gasoline/analysis , Particulate Matter/analysis , Particulate Matter/chemistry , Vehicle Emissions/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Reactive Oxygen Species/analysis , Temperature
2.
J Air Waste Manag Assoc ; 51(4): 562-73, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11321913

ABSTRACT

The purpose of this research was to determine the efficiency of a polymer biocover for the abatement of H2S and NH3 emissions from an east-central Missouri swine lagoon with a total surface area of 7800 m2. The flux rate of NH3, H2S, and CH4 was monitored continuously from two adjacent, circular (d = 66 m) control and treatment plots using a nonintrusive, micrometeorological method during three independent sampling periods that ranged between 52 and 149 hr. Abatement rates were observed to undergo a temporal acclimation event in which NH3 abatement efficiency improved from 17 to 54% (p = < 0.0001 to 0.0005) and H2S abatement efficiency improved from 23 to 58% (p < 0.0001) over a 3-month period. The increase in abatement efficiency for NH3 and H2S over the sampling period was correlated with the development of a stable anaerobic floc layer on the bottom surface of the biocover that reduced mass transfer of NH3 and H2S across the surface. Analysis of methanogenesis activity showed that the biocover enhanced the rate of anaerobic digestion by 25% when compared with the control. The biocover-enhanced anaerobic digestion process was shown to represent an effective mechanism to counteract the accumulation of methanogenic substrates in the biocovered lagoon.


Subject(s)
Air Pollution/prevention & control , Ammonia/analysis , Hydrogen Sulfide/analysis , Refuse Disposal/methods , Agriculture , Air Pollution/analysis , Animals , Biodegradation, Environmental , Feces , Microclimate , Polymers , Swine , Volatilization
3.
ScientificWorldJournal ; 1 Suppl 2: 691-8, 2001 Nov 20.
Article in English | MEDLINE | ID: mdl-12805823

ABSTRACT

The responses of Acala cotton (Gossypium hirsutum L.) in California to a range of applied nitrogen (N) treatments were investigated in a 5-year, multisite experiment. The experiment's goals were to identify crop growth and yield responses to applied N and provide information to better assess the utility of soil residual N estimates in improving fertilizer management. Baseline fertilizer application rates for the lowest applied N treatments were based on residual soil nitrate-N (NO3-N) levels determined on soil samples from the upper 0.6 m of the soil collected prior to spring N fertilization and within 1 week postplanting each year. Results have shown positive cotton lint yield responses to increases in applied N across the 56 to 224 kg N/ha range in only 41% (16 out of 39) of test sites. Soil NO3-N monitoring to a depth of 2.4 m in the spring (after planting) and fall (postharvest) indicate most changes in soil NO3- occur within the upper 1.2 m of soil. However, some sites (those most prone to leaching losses of soluble nutrients) also exhibited net increases in soil NO3-N in the 1.2- to 2.4-m depth zone when comparing planting time vs. postharvest data. The lack of yield responses and soil NO3-N accumulations at some sites indicate that more efforts should be put into identifying the amount of plant N requirements that can be met from residual soil N, rather than solely from fertilizer N applications.


Subject(s)
Gossypium/drug effects , Gossypium/metabolism , Nitrogen/metabolism , Nitrogen/pharmacology , California , Fertilizers , Gossypium/growth & development , Hot Temperature , Nitrates/analysis , Rain , Soil/analysis , Time Factors
4.
Biochem J ; 325 ( Pt 3): 693-700, 1997 Aug 01.
Article in English | MEDLINE | ID: mdl-9271090

ABSTRACT

Leukaemia inhibitory factor (LIF) is a polyfunctional cytokine that is known to require at least two distinct receptor components (LIF receptor alpha-chain and gp130) in order to form a high-affinity, functional, receptor complex. Human LIF binds with unusually high affinity to a naturally occurring mouse soluble LIF receptor alpha-chain, and this property was used to purify a stable complex of human LIF and mouse LIF receptor alpha-chain from pregnant-mouse serum. Recombinant soluble human gp130 was expressed, with a FLAG(R) epitope (DYKDDDDK) at the N-terminus, in the methylotropic yeast Pichia pastoris and purified using affinity chromatography. The formation of a trimeric complex in solution was established by native gel electrophoresis, gel-filtration chromatography, sedimentation equilibrium analysis, surface plasmon resonance spectroscopy and chemical cross-linking. The stoichiometry of this solution complex was 1:1:1, in contrast with that of the complex of interleukin-6, the interleukin-6-specific low-affinity receptor subunit and gp130, which is 2:2:2.


Subject(s)
Growth Inhibitors/chemistry , Lymphokines/chemistry , Antigens, CD/genetics , Antigens, CD/metabolism , Cytokine Receptor gp130 , Growth Inhibitors/genetics , Growth Inhibitors/metabolism , Humans , Interleukin-6/metabolism , Leukemia Inhibitory Factor , Lymphokines/genetics , Lymphokines/metabolism , Membrane Glycoproteins/genetics , Membrane Glycoproteins/metabolism , Pichia/genetics , Protein Binding , Recombinant Fusion Proteins/genetics , Signal Transduction , Solutions
5.
J Biol Chem ; 272(14): 9474-80, 1997 Apr 04.
Article in English | MEDLINE | ID: mdl-9083087

ABSTRACT

Interleukin-4 (IL-4) and interleukin-13 (IL-13) are structurally and functionally related cytokines which play an important role in the regulation of the immune response to infection. The functional similarity of IL-4 and IL-13 can be explained, at least in part, by the common components that form their cell surface receptors, namely the IL-4 receptor alpha-chain (IL-4Ralpha) and the IL-13 receptor alpha-chain (IL-13Ralpha). Soluble forms of the IL-4Ralpha have also been described and implicated in modulating the effect of IL-4. In this paper we describe the presence of a 45,000-50,000 Mr IL-13-binding protein (IL-13BP) in the serum and urine of mice. This protein binds IL-13 with a 100-300-fold higher affinity (KD = 20-90 pM) than does the cloned IL-13Ralpha (KD = 3-10 nM). In addition to this functional difference, the IL-13BP appears to be structurally and antigenically distinct from the IL-13Ralpha. Finally, unlike the cloned receptor, the IL-13BP acts as a potent inhibitor of IL-13 binding to its cell surface receptor, raising the possibility that it may be used to modulate the effects of IL-13 in vivo.


Subject(s)
Antigens, CD/chemistry , Interleukin-13/metabolism , Interleukin-4/metabolism , Receptors, Interleukin/analysis , Receptors, Interleukin/chemistry , Animals , Antigens, CD/genetics , Chromatography, Affinity , Chromatography, Gel , Cloning, Molecular , Electrophoresis, Polyacrylamide Gel , Glycosylation , Interleukin-13/urine , Interleukin-13 Receptor alpha1 Subunit , Mice , Molecular Weight , Rabbits , Receptors, Interleukin/genetics , Receptors, Interleukin-13 , Receptors, Interleukin-4 , Serine Endopeptidases/metabolism
6.
Environ Monit Assess ; 39(1-3): 199-213, 1996 Jan.
Article in English | MEDLINE | ID: mdl-24198006

ABSTRACT

For the sustainable development of forest land, as recently prescribed by the Canadian Forest Strategy, a land classification project in northern Newfoundland was initiated to support the local forest management activities. The method adopted here is a modification of the Canadian Committee for Ecological Land Classification's (CCELC) system, and it applies various levels of mapping to uniform areas based on geomorphology, soils, vegetation, climate, water, and fauna.In this study, all CCELC levels were mapped; resulting maps were digitized and imported into a Geographic Informations System (GIS). The GIS data base contained the following maps: 1) digital terrain model, 2) bedrock geology, 3) surficial geology, 4) forest inventory, and 5) various levels of the ecological land classification, including Vegetation Types at the lowest level. In addition to the mapping, mensurational data were analyzed to provide stand and stock tables for each of the forest types, including growth curves that could be entered into specific forest growth modelling systems to predict wood supply scenarios based upon different management interventions.

7.
Environ Monit Assess ; 39(1-3): 353-64, 1996 Jan.
Article in English | MEDLINE | ID: mdl-24198015

ABSTRACT

Most existing systems of forest site classification attempt to combine vegetation, soil, terrain, geology, climatic and hydrologic factors. The current paper describes an ongoing project to assess the relationship of these factors to forest site capability in Newfoundland. Through the description and classification of forest inventory plots, this project is providing productivity data for species, descriptions of vegetational succession, growth and yield projections, as well as an indication of soil type variation within Forest Management Districts.The cooperative, multi-agency approach employed in this project has benefited all parties concerned, and has resulted in a mix of expertise and focus of resources that would not be possible within one agency. A large and valuable bank of vegetation, soil and site data is being acquired. Elements of the project include: 1) establishment of permanent forest inventory sample plots, in Management Districts throughout the province; 2) training of forest inventory crews so that they recognize forest vegetation, accurately prepare soil descriptions and undertake soil sampling; 3) laboratory analyses of soil samples for chemical and physical parameters, and integration of these results into the forest site classification; and, 4) formal reporting of the forest site classification, including improved descriptions of Damman Forest Site Types (FSTs) and soils.

8.
Environ Monit Assess ; 39(1-3): 509-30, 1996 Jan.
Article in English | MEDLINE | ID: mdl-24198026

ABSTRACT

Red pine (Pinus resinosa Ait.) is rare (< 15 000 mature trees) in Newfoundland and is known from only 22 locations in the central region. Red pine occupies 3 major site types in Newfoundland: 1) red pine on medium-textured sands (RP1), 2) red pine on coarse-textured glaciofluvial deposits (RP2), and 3) red pine on Folisols over bedrock (RP3). The succession of red pine site types after cutting is from red pine to Kalmia-black spruce (Picea mariana (Mill.) B.S.P.) for RP1, and to Cladonia-Kalmia-black spruce for types RP2 and RP3. Succession after fire is usually to the pre-fire type, but this depends on the severity of the fire.Although occupying a relatively poor site, red pine at 60-70 years reaches heights in excess of 18 m, dbh in excess of 40 cm, and individual tree volumes greater than 1 m(3) were recorded in 75 stemanalyzed fire-killed trees. Black spruce on that same site produces less than one-third that volume in 60 years. Merchantable volume of 140-280 m(3) ha(-1) were recorded i.e., Canada Land Inventory (CLI) forest capability class 5 and class 4 ratings. This raises the CLI rating two capability classes if red pine were occupying these poor quality sites over black spruce. In terms of nutrition, even the best growing red pine are nitrogen (N) deficient as shown by foliar analysis. All natural stands have foliar N concentrations below 1.3% which is the critically low level shown in the literature. Immediately after fire, foliar concentrations reach this level but are usually about 1% or less. Most other nutrients are low but are within the generally reported adequate levels in testing for P, K, Ca and Mg.Fire influences soil nutrient availability as pH increases in the RP1 type. Burning temperature also affects soil pH and the understory vegetation. The RP2 type loses more N in hotter burns on this site type and more N is tied up in these ortstein hardpan soils. The pattern of regeneration following wildfire is related to slope, density, age and species mixture of the stand as well as the thickness and composition of the duff layer.

11.
Ultrason Imaging ; 7(4): 300-20, 1985 Oct.
Article in English | MEDLINE | ID: mdl-3914771

ABSTRACT

A reconstruction algorithm is presented which possesses a simple scanning geometry and promises higher resolution than conventional transmission mode diffraction tomography algorithms. This broad-band reflection mode algorithm inherently lacks a certain amount of low frequency information but an estimate of the information is recovered by spectral extrapolation. The resolution of the algorithm will be shown to be limited by the bandwidth and physical size of the single plane wave transducer, as well as the Born approximation.


Subject(s)
Tomography/methods , Ultrasonography/methods , Computers
14.
Appl Environ Microbiol ; 42(5): 916-7, 1981 Nov.
Article in English | MEDLINE | ID: mdl-7316507

ABSTRACT

Soil fungi, including Aspergillus fischeri, Penicillium piceum, Penicillium nigricans, and Penicillium raistrickii, produced a tremorgenic toxin previously described as toxin X. Chemical analysis showed that this toxin was predominantly verruculogen.


Subject(s)
Aspergillus/metabolism , Indoles/biosynthesis , Mycotoxins/biosynthesis , Penicillium/metabolism , Soil Microbiology , England , Wales
15.
Res Vet Sci ; 31(2): 213-8, 1981 Sep.
Article in English | MEDLINE | ID: mdl-6798656

ABSTRACT

Four groups of six 12-week-old male Friesian calves were fed diets containing 390 to 540 microgram ochratoxin A per kg, 320 to 500 microgram ochratoxin A plus 12 to 13 microgram aflatoxin B1 per kg, 10 to 13 microgram aflatoxin B1 per kg, or a control diet containing neither toxin. At the end of the 87-day experiment there was no evidence of kidney or liver damage in any group of animals as judged by serial plasma and urine enzyme assays, haematological examinations including the assay of blood coagulation factors, gross appearance at autopsy or histopathological assessment at the light microscopic level. Nor was there any significant alteration in serum IgA, IgM, IgG1 and IgG2 levels or in titres to environmental bacterial and viral antigens. Trace amounts of ochratoxin A were detected in kidneys of five out of the 12 calves exposed to this toxin but all 12 kidneys contained residues of the metabolite ochratoxin alpha (less than 5 to 10 microgram/kg). Traces of aflatoxin B1 and M1 were detected in the liver of one of the 12 calves exposed to aflatoxin B1 but nine kidneys contained the metabolite aflatoxin M1 (less than 0.01 to 0.03 microgram/kg). There was no evidence of interaction between the two toxins.


Subject(s)
Aflatoxins/toxicity , Animal Feed/toxicity , Cattle/metabolism , Edible Grain , Hordeum , Ochratoxins/toxicity , Aflatoxin B1 , Aflatoxins/metabolism , Animals , Cattle/blood , Cattle/growth & development , Kidney/metabolism , Male , Ochratoxins/metabolism
16.
J Assoc Off Anal Chem ; 64(4): 961-3, 1981 Jul.
Article in English | MEDLINE | ID: mdl-6792181

ABSTRACT

A quantitative procedure widely used in European Economic Community (EEC) countries has been successfully scaled down to produce a rapid method for determination of aflatoxin B1 (and other aflatoxins) in animal feeds. Without modification, the method may be used for simultaneous ochratoxin A determination in simple feeds, but a slightly different extraction procedure is required for compound feeds. Validity of the method has been demonstrated by comparison with the full EEC procedure for aflatoxin B1 and the Nesheim method for ochratoxin A. Analyses may be completed within 2 h and there is a considerable savings in materials over the 2 reference methods. The procedure is also less hazardous because volumes of toxic extract are small, and the operator is exposed to minimum solvent vapor.


Subject(s)
Aflatoxins/analysis , Animal Feed/analysis , Ochratoxins/analysis , Aflatoxin B1 , Chromatography, Thin Layer/methods
18.
Vet Rec ; 107(11): 249-52, 1980 Sep 13.
Article in English | MEDLINE | ID: mdl-7257101

ABSTRACT

Over a period of 13 years 740 samples of various animal feedstuffs were analysed for the presence of aflatoxin B1. Nearly 500 were suspected of causing disease in farm animals but aflatoxin B1 could be detected in only 13.6 per cent of them. Groundnut meal samples nearly always contained the toxin but compounded feeds were contaminated to a varying extent. In particular, none could be detected in 62 poultry feeds. Where mycotoxicosis was suspected in dairy cattle, aflatoxin B1 was present at levels of more than 30 micrograms per kg in about 27 per cent of associated feed samples. In other dairy feeds (178 samples) this level of contamination was present in only about 9 per cent of samples. Concentrations of aflatoxin B1 likely to produce toxic effects (100 micrograms per kg and above) were present in about 4 per cent of suspect dairy concentrates but in 1 per cent or less of others. Contamination of dairy concentrates with aflatoxin B1 is usually at such a level that cows probably excrete the toxic metabolite aflatoxin M1 in milk at very low concentrations of 0.1 micrograms per litre or less.


Subject(s)
Aflatoxins/analysis , Animal Feed/analysis , Animals , Cattle , Nuts/analysis , Poultry , Swine
20.
Lancet ; 2(8192): 435-8, 1980 Aug 30.
Article in English | MEDLINE | ID: mdl-6106094

ABSTRACT

Occasionally patients present with stage III breast carcinoma so advanced that local radiotherapy is unlikely to achieve more than a partial and temporary local regression. 3 such patients with grossly advanced cancer involving virtually the whole of the breast, skin, and underlying muscle were treated with a regimen of intra-arterial infusion chemotherapy as basal treatment before planned irradiation. All 3 patients responded significantly to intra-arterial chemotherapy and subsequent definitive radiotherapy seems to have resulted in total regression of tumour and involved nodes in 2 patients. In the 3rd patient the response of the tumour mass to subsequent radiotherapy was considerable but incomplete; subsequent surgical resection seems to have eradicated the small foci of residual disease buried in fibrous tissue in the breast and one axillary node. All patients were given routine adjuvant chemotherapy after completion of irradiation. A 4th patient with a huge fungating breast carcinoma which was bleeding and foul-smelling who also had evidence of liver metastasis (stage IV disease) was treated in a similar manner. Local tumour regression was achieved and although the patient still requires treatment for metastatic disease there is no evidence of residual carcinoma in the breast or axilla 12 months after treatment. Further investigation of this treatment seems worthwhile, since it may be effective not only in the management of large breast cancers but also in patients with less advanced disease who refuse mastectomy or wish to avoid it.


Subject(s)
Antineoplastic Agents/administration & dosage , Breast Neoplasms/drug therapy , Adult , Breast Neoplasms/pathology , Breast Neoplasms/radiotherapy , Drug Therapy, Combination , Female , Humans , Infusions, Intra-Arterial , Middle Aged , Neoplasm Metastasis
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