931 resultados para Vermont and Canada Railroad Co.


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In the area of international environmental law this thesis proposes the formulation of one-step planning and permitting regulation for the integrated utilisation of new surface mines as depositories for municipal solid waste. Additionally, the utilisation of abandoned and currently operated surface mines is proposed as solid waste landfills as an integral step in their reclamation. Existing laws, litigation and issues in the United Kingdom, the U.S. and Canada are discussed because of their common legal system, language and heritage. The critical shortage of approved space for disposal of solid waste has caused an urgent and growing problem for both the waste disposal industry and society. Surface mining can serve three important environmental and societal functions inuring to the health and welfare of the public: (1) providing basic minerals for goods and construction; (20 sequentially, to provide critically needed, safe burial sites for society's wastes, and (3) to conserve land by dual purpose use and to restore derelict land to beneficial surface use. Currently, the first two functions are treated environmentally, and in regulation, as two different siting problems, yet they both are earth-disturbing and excavating industries requiring surface restoration. The processes are largely duplicative and should be combined for better efficiency, less earth disturbance, conservation of land, and for fuller and better reclamation of completed surface mines returning the surfaces to greater utility than present mined land reclamation procedures. While both industries are viewed by a developed society and its communities as "bad neighbours", they remain essential and critical for mankind's existence and welfare. The study offers successful examples of the integrated process in each country. The study argues that most non-fuel surface mine openings, if not already safe, can economically, through present containment technology, be made environmentally safe for use as solid waste landfills. Simultaneously, the procedure safeguards and monitors protection of ground and surface waters from landfill contamination.

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Two aspects of gold mineralisation in the Caledonides of the British Isles have been investigated: gold-telluride mineralisation at Clogau Mine, North Wales; and placer gold mineralisation in the Southern Uplands, Scotland. The primary ore assemblage at Clogau Mine is pyrite, arsenopyrite, cobaltite, pyrrhotine, chalcopyrite, galena, tellurbismuth, tetradymite, altaite, hessite, native gold, wehrlite, hedleyite, native bismuth, bismuthunite and various sulphosalts. The generalised paragenesis is early Fe, Co, Cu, As and S species, and later minerals of Pb, Bi, Ag, Au, Te, Sb. Electron probe micro-analysis (EPMA) of complex telluride-sulphide intergrowths suggests that these intergrowths formed by co-crystallisation/replacement processes and not exsolution. Minor element chemical variation, in the sulphides and tellurides, indicates that antimony and cadmium are preferentially partitioned into telluride minerals. Mineral stability diagrams suggest that during gold deposition log bf aTe2 was between -7.9 and -9.7 and log bf aS2 between -12.4 and -13.8. Co-existing mineral assemblages indicate that the final stages of telluride mineralisation were between c. 250 - 275oC. It is suggested that the high-grade telluride ore shoot was the result of remobilisation of Au, Bi, Ag and Te from low grade mineralisation elsewhere within the vein system, and that gold deposition was brought about by destabilisation of gold chloride complexes by interaction with graphite, sulphides and tellurbismuth. Scanning electron microscopy of planer gold grains from the Southern Uplands, Scotland, indicates that detailed studies on the morphology of placer gold can be used to elucidate the history of gold in the placer environment. In total 18 different morphological characteristics were identified. These were divided on an empirical basis, using the relative degree of mechanical attrition, into proximal and distal characteristics. One morphological characteristic (a porous/spongy surface at high magnification) is considered to be chemical in origin and represent the growth of `new' gold in the placer environment. The geographical distribution of morphological characteristics has been examined and suggests that proximal placer gold is spatially associated with the Loch Doon, Cairsphairn and Fleet granitoids. Quantitative EPMA of the placer gold reveals two compositional populations of placer gold. Examination of the geographical distribution of fineness suggests a loose spatial association between granitoids and low fineness placer gold. Also identified was chemically heterogeneous placer gold. EPMA studies of these heterogeneities allowed estimation of annealing history limits, which suggest that the heterogeneities formed between 150 and 235oC. It is concluded, on the basis of relationships between morphology and composition, that there are two types of placer gold in the Southern Uplands: (i) placer gold which is directly inherited from a hypogene source probably spatially associated with granitoids; and (ii) placer gold that has formed during supergene processes.

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Periodontitis, a ubiquitous chronic inflammatory disease, is associated with reduced antioxidant defences and neutrophil hyperactivity in terms of reactive oxygen species (ROS) generation. Its phenotype is thus characterized by oxidative stress. We have determined the effect of antioxidant micronutrients ascorbate and α-tocopherol on neutrophil ROS generation. Peripheral neutrophils from periodontally-healthy individuals (n = 20) were challenged with phorbol myristate acetate, IgG-opsonised Staphylococcus aureus, Fusobacterium nucleatum or PBS in the presence and absence of micronutrients (50 μM). Total and extracellular ROS were measured by luminol and isoluminol chemiluminescence respectively. Total and extracellular unstimulated, baseline ROS generation was unaffected by α-tocopherol, but inhibited by ascorbate and a combination of both micronutrients. Fcγ-receptor (Fcγ-R)-stimulated total or extracellular ROS generation was not affected by the presence of individual micronutrients. However, the combination significantly reduced extracellular FcγR-stimulated ROS release. Neither micronutrient inhibited TLR-stimulated total ROS, but the combination caused inhibition. Ascorbate and the micronutrient combination, but not α-tocopherol, inhibited extracellular ROS release by TLR-stimulated cells. Such micronutrient effects in vivo could be beneficial in reducing collateral tissue damage in chronic inflammatory diseases, such as periodontitis, while retaining immune-mediated neutrophil function. © The Author(s) 2012 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

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The present paper deals with experimentation of ZrO2 and Al2O3-supported catalysts for conversion of naphthalene, chosen as tar model compound of pyrolysis or gasification syngas. In particular, the reforming capacity of active metals and promoters such as Co, Ni, Fe, Cr, Ce and Pt was tested in a fixed bed reactor at temperature from 400 to 900 °C. As regards ZrO2-supported catalysts, the best results were achieved by the Ni/Fe/Pt catalyst with 96% naphthalene conversion, 78% and 280% as CO and H2 production yield at 800 °C. Regarding Al2O3-supported catalysts, they were more active on average than the zirconia ones, achieving a very good performance even at 500 °C (90–100% naphthalene conversion, 30–40% CO yield and 300–350% H2 yield at 550 °C). Influence of different amounts of alumina, montmorillonite and carbon on carrier composition as well as pellets’ size were also studied. Both zirconia and alumina catalysts showed deactivation at higher temperatures due to coke deposition, resulting in a strong H2 production drop. Regeneration of catalysts by O2 and steam as well as activation by H2 were also studied. The activated catalyst was able to convert more than 99% naphthalene at 450 °C with a CO and H2 production yield of 26% and 420%, respectively.

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BACKGROUND & AIMS: The transferrin receptor (CD71) is up-regulated in duodenal biopsy samples from patients with active celiac disease and promotes retrotransport of secretory immunolglobulin A (SIgA)-gliadin complexes. We studied intestinal epithelial cell lines that overexpress CD71 to determine how interactions between SIgA and CD71 promote transepithelial transport of gliadin peptides. METHODS: We analyzed duodenal biopsy specimens from 8 adults and 1 child with active celiac disease. Caco-2 and HT29-19A epithelial cell lines were transfected with fluorescence-labeled small interfering RNAs against CD71. Interactions among IgA, CD71, and transglutaminase 2 (Tgase2) were analyzed by flow cytometry, immunoprecipitation, and confocal microscopy. Transcytosis of SIgACD71 complexes and intestinal permeability to the gliadin 3H-p3149 peptide were analyzed in polarized monolayers of Caco-2 cells. RESULTS: Using fluorescence resonance energy transfer and in situ proximity ligation assays, we observed physical interactions between SIgA and CD71 or CD71 and Tgase2 at the apical surface of enterocytes in biopsy samples and monolayers of Caco-2 cells. CD71 and Tgase2 were co-precipitated with SIgA, bound to the surface of Caco-2 cells. SIgACD71 complexes were internalized and localized in early endosomes and recycling compartments but not in lysosomes. In the presence of celiac IgA or SIgA against p3149, transport of intact 3H-p3149 increased significantly across Caco-2 monolayers; this transport was inhibited by soluble CD71 or Tgase2 inhibitors. CONCLUSIONS: Upon binding to apical CD71, SIgA (with or without gliadin peptides) enters a recycling pathway and avoids lysosomal degradation; this process allows apicalbasal transcytosis of bound peptides. This mechanism is facilitated by Tgase2 and might be involved in the pathogenesis of celiac disease.

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Biopharmaceuticals are finding wide applications in the management of diverse disease conditions. Pulmonary delivery of proteins may constitute an effective and efficient non-invasive alternative to parenteral delivery, which is currently the main route of administration of biopharmaceutical drugs. A particular area, in which pulmonary delivery of peptides and proteins may find ready application, is in the local delivery of antimicrobial peptides and proteins to the airway, a measure that could potentially bring about improvements to currently available antipseudomonal therapies. This thesis has therefore sought to develop inhalable antimicrobial proteins in combination with antibiotics that have particularly good antimicrobial activity against Pseudomonas aeruginosa infections in the respiratory tract of people with cystic fibrosis (CF). Through process optimisation, a suitable spray drying method was developed and used for the preparation of active, inhalable dry powder formulations of the antimicrobial protein, lactoferrin, and aminoglycosides (tobramycin and gentamicin). The physicochemical properties, aerosolisation performance and the antibacterial properties of the various spray-dried formulations were assessed. In addition, a relevant in vitro cellular model was employed to investigate the potential cytotoxic and pro-inflammatory effects of the various formulations on four bronchial human epithelial cells together with their effectiveness at reducing bacterial colonies when administered on to biofilm co-cultured on the epithelial cells. It was found that following spray drying the particles obtained were mostly spherical, amorphous and possessed suitable aerosolisation characteristics. The various spray-dried antimicrobial proteins (lactoferrin or apo lactoferrin) and co-spray dried combinations of the proteins and aminoglycosides were found to exhibit bactericidal activity against planktonic and biofilms of P. aeruginosa. In general, the spray drying process was found not to significantly affect the antimicrobial activities of the protein. Treatment of the different bronchial epithelial cell lines with the antimicrobial formulations showed that the various formulations were non-toxic and that the co-spray dried combinations significantly reduced established P. aeruginosa biofilms on the four bronchial epithelial cells. Overall, the results from this thesis demonstrates that spray drying could potentially be employed to prepare inhalable antimicrobial agents comprised of proteins and antibiotics. These new combinations of proteins and aminoglycosides has promising applications in the management of P. aeruginosa in the airway of cystic fibrosis patients.

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Among student and young professional migrants to the UK the opportunity for a global or cosmopolitan experience emerges as a motivating factor for migration. This article takes the example of student and young professional migrants to the UK from the South Indian state of Tamil Nadu, and explores how this cosmopolitan ambition plays out in the formation of UK social networks. Two 'types' of research participant are identified; 'self-conscious cosmopolitans' whose social networks are cross-ethnic, and others whose networks are largely co-ethnic and who are often derided by their self-consciously cosmopolitan counterparts as 'clannish' or 'cliquey'. The article asks how ethnicity emerges as salient (or not) in these migrants' talk and practice around UK social network formations. It then considers whether a co-ethnic social network necessarily limits the cosmopolitan experience, or whether this interpretation reflects a narrow understanding of cosmopolitanism which excludes the multiple inter-cultural encounters these migrants experience in their everyday lives. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

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For 35 years, Arnstein's ladder of citizen participation has been a touchstone for policy makers and practitioners promoting user involvement. This article critically assesses Arnstein's writing in relation to user involvement in health drawing on evidence from the United Kingdom, the Netherlands, Finland, Sweden and Canada. Arnstein's model, however, by solely emphasizing power, limits effective responses to the challenge of involving users in services and undermines the potential of the user involvement process. Such an emphasis on power assumes that it has a common basis for users, providers and policymakers and ignores the existence of different relevant forms of knowledge and expertise. It also fails to recognise that for some users, participation itself may be a goal. We propose a new model to replace the static image of a ladder and argue that for user involvement to improve health services it must acknowledge the value of the process and the diversity of knowledge and experience of both health professionals and lay people.

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Pre-eclampsia, a pregnancy-specific multi-organ syndrome characterized by widespread endothelial damage, is a new risk factor for cardiovascular disease. No therapies exist to prevent or treat this condition, even to achieve a modest improvement in pregnancy length or birth weight. Co-administration of soluble VEGFR-1 [VEGF (vascular endothelial growth factor) receptor-1; more commonly known as sFlt-1 (soluble Fms-like tyrosine kinase-1)] and sEng (soluble endoglin) to pregnant rats elicits severe pre-eclampsia-like symptoms. These two anti-angiogenic factors are increased dramatically prior to the clinical onset of pre-eclampsia and are quite possibly the 'final common pathway' responsible for the accompanying signs of hypertension and proteinuria as they can be reversed by VEGF administration in animal models. HO-1 (haem oxygenase-1), an anti-inflammatory enzyme, and its metabolite, CO (carbon monoxide), exert protective effects in several organs against oxidative stimuli. In a landmark publication, we showed that the HO-1 pathway inhibits sFlt-1 and sEng in cultured cells and human placental tissue explants. Both CO and NO (nitric oxide) promote vascular homoeostasis and vasodilatation, and activation of VEGFR-1 or VEGFR-2 induced eNOS (endothelial nitric oxide synthase) phosphorylation, NO release and HO-1 expression. Our studies established the HO-1/CO pathway as a negative regulator of cytokine-induced sFlt-1 and sEng release and eNOS as a positive regulator of VEGF-mediated vascular morphogenesis. These findings provide compelling evidence for a protective role of HO-1 in pregnancy and identify it as a target for the treatment of pre-eclampsia. Any agent that is known to up-regulate HO-1, such as statins, may have potential as a therapy. Any intervention achieving even a modest prolongation of pregnancy or amelioration of the condition could have a significant beneficial health impact worldwide.

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Placental villous development requires the co-ordinated action of angiogenic factors on both endothelial and trophoblast cells. Like vascular endothelial growth factor (VEGF), VEGF-C increases vascular permeability, stimulates endothelial cell proliferation and migration. In the present study, we investigated the expression of VEGF-C and its receptors VEGFR-3 and VEGFR-2 in normal and intrauterine growth-restricted (IUGR) placenta. Immunolocalisation studies showed that like VEGF and VEGFR-1, VEGF-C, VEGFR-3 and VEGFR-2 co-localised to the syncytiotrophoblast, to cells in the maternal decidua, as well as to the endothelium of the large placental blood vessels. Western blot analysis demonstrated a significant decrease in placental VEGF-C and VEGFR-3 protein expression in severe IUGR as compared to gestationally-matched third trimester pregnancies. Conditioned medium from VEGF-C producing pancreatic carcinoma (Suit-2) and endometrial epithelial (Hec-1B) cell lines caused an increased association of the phosphorylated extracellular signal regulated kinase (ERK) in VEGFR-3 immunoprecipitates from spontaneously transformed first trimester trophoblast cells. VEGF121 caused dose-dependant phosphorylation of VEGFR-2 in trophoblast cells as well as stimulating DNA synthesis. In addition, premixing VEGF165 with heparin sulphate proteoglycan potentiated trophoblast proliferation and the association of phospho-ERK with the VEGFR-2 receptor. VEGF165-mediated DNA synthesis was inhibited by anti-VEGFR-2 neutralising antibody. The results demonstrate functional VEGFR-2 and VEGFR-3 receptors on trophoblast and suggest that the decreased expression of VEGF-C and VEGFR-3 may contribute to the abnormal villous development observed in IUGR placenta.

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In this paper a methodology for evaluation of information security of objects under attacks, processed by methods of compression, is represented. Two basic parameters for evaluation of information security of objects – TIME and SIZE – are chosen and the characteristics, which reflect on their evaluation, are analyzed and estimated. A co-efficient of information security of object is proposed as a mean of the coefficients of the parameter TIME and SIZE. From the simulation experiments which were carried out methods with the highest co-efficient of information security had been determined. Assessments and conclusions for future investigations are proposed.

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Coherent optical orthogonal frequency division multiplexing (CO-OFDM) is an attractive transmission technique to virtually eliminate intersymbol interference caused by chromatic dispersion and polarization-mode dispersion. Design, development, and operation of CO-OFDM systems require simple, efficient, and reliable methods of their performance evaluation. In this paper, we demonstrate an accurate bit error rate estimation method for QPSK CO-OFDM transmission based on the probability density function of the received QPSK symbols. By comparing with other known approaches, including data-aided and nondata-aided error vector magnitude, we show that the proposed method offers the most accurate estimate of the system performance for both single channel and wavelength division multiplexing QPSK CO-OFDM transmission systems. © 2014 IEEE.

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The poor retention and efficacy of instilled drops as a means of delivering drugs to the ophthalmic environment is well-recognised. The potential value of contact lenses as a means of ophthalmic drug delivery, and consequent improvement of pre-corneal retention is one obvious route to the development of a more effective ocular delivery system. Furthermore, the increasing availability and clinical use of daily disposable contact lenses provides the platform for the development of viable single-day use drug delivery devices based on existing materials and lenses. In order to provide a basis for the effective design of such devices, a systematic understanding of the factors affecting the interaction of individual drugs with the lens matrix is required. Because a large number of potential structural variables are involved, it is necessary to achieve some rationalisation of the parameters and physicochemical properties (such as molecular weight, charge, partition coefficients) that influence drug interactions. Ophthalmic dyes and structurally related compounds based on the same core structure were used to investigate these various factors and the way in which they can be used in concert to design effective release systems for structurally different drugs. Initial studies of passive diffusional release form a necessary precursor to the investigation of the features of the ocular environment that over-ride this simple behaviour. Commercially available contact lenses of differing structural classifications were used to study factors affecting the uptake of the surrogate actives and their release under 'passive' conditions. The interaction between active and lens material shows considerable and complex structure dependence, which is not simply related to equilibrium water content. The structure of the polymer matrix itself was found to have the dominant controlling influence on active uptake; hydrophobic interaction with the ophthalmic dye playing a major role. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

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Purpose: The aim of this work was to optimize biodegradable polyester poly(glycerol adipate-co-ω-pentadecalactone), PGA-co-PDL, microparticles as sustained release (SR) carriers for pulmonary drug delivery. Methods: Microparticles were produced by spray drying directly from double emulsion with and without dispersibility enhancers (L-arginine and L-leucine) (0.5-1.5%w/w) using sodium fluorescein (SF) as a model hydrophilic drug. Results: Spray-dried microparticles without dispersibility enhancers exhibited aggregated powders leading to low fine particle fraction (%FPF) (28.79±3.24), fine particle dose (FPD) (14.42±1.57 μg), with a mass median aerodynamic diameter (MMAD) 2.86±0.24 μm. However, L-leucine was significantly superior in enhancing the aerosolization performance ( L-arginine:%FPF 27.61±4.49-26.57±1.85; FPD 12.40±0.99-19.54±0.16 μg and MMAD 2.18±0.35-2. 98±0.25 μm, L-leucine:%FPF 36.90±3.6-43.38±5. 6; FPD 18.66±2.90-21.58±2.46 μg and MMAD 2.55±0.03-3. 68±0.12 μm). Incorporating L-leucine (1.5%w/w) reduced the burst release (24.04±3.87%) of SF compared to unmodified formulations (41.87±2.46%), with both undergoing a square root of time (Higuchi's pattern) dependent release. Comparing the toxicity profiles of PGA-co-PDL with L-leucine (1.5%w/w) (5 mg/ml) and poly(lactide-co-glycolide), (5 mg/ml) spray-dried microparticles in human bronchial epithelial 16HBE14o-cell lines, resulted in cell viability of 85.57±5.44 and 60.66±6.75%, respectively, after 72 h treatment. Conclusion:The above data suggest that PGA-co-PDL may be a useful polymer for preparing SR microparticle carriers, together with dispersibility enhancers, for pulmonary delivery. © Springer Science+Business Media, LLC 2011.

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CO vibrational spectra over catalytic nanoparticles under high coverages/pressures are discussed from a DFT perspective. Hybrid B3LYP and PBE DFT calculations of CO chemisorbed over Pd4 and Pd13 nanoclusters, and a 1.1 nm Pd38 nanoparticle, have been performed in order to simulate the corresponding coverage dependent infrared (IR) absorption spectra, and hence provide a quantitative foundation for the interpretation of experimental IR spectra of CO over Pd nanocatalysts. B3LYP simulated IR intensities are used to quantify site occupation numbers through comparison with experimental DRIFTS spectra, allowing an atomistic model of CO surface coverage to be created. DFT adsorption energetics for low CO coverage (θ → 0) suggest the CO binding strength follows the order hollow > bridge > linear, even for dispersion-corrected functionals for sub-nanometre Pd nanoclusters. For a Pd38 nanoparticle, hollow and bridge-bound are energetically similar (hollow ≈ bridge > atop). It is well known that this ordering has not been found at the high coverages used experimentally, wherein atop CO has a much higher population than observed over Pd(111), confirmed by our DRIFTS spectra for Pd nanoparticles supported on a KIT-6 silica, and hence site populations were calculated through a comparison of DFT and spectroscopic data. At high CO coverage (θ = 1), all three adsorbed CO species co-exist on Pd38, and their interdiffusion is thermally feasible at STP. Under such high surface coverages, DFT predicts that bridge-bound CO chains are thermodynamically stable and isoenergetic to an entirely hollow bound Pd/CO system. The Pd38 nanoparticle undergoes a linear (3.5%), isotropic expansion with increasing CO coverage, accompanied by 63 and 30 cm− 1 blue-shifts of hollow and linear bound CO respectively.