893 resultados para NOES- Nose Only Exposure System


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A new domain-specific, reconfigurable system-on-a-chip (SoC) architecture is proposed for video motion estimation. This has been designed to cover most of the common block-based video coding standards, including MPEG-2, MPEG-4, H.264, WMV-9 and AVS. The architecture exhibits simple control, high throughput and relatively low hardware cost when compared with existing circuits. It can also easily handle flexible search ranges without any increase in silicon area and can be configured prior to the start of the motion estimation process for a specific standard. The computational rates achieved make the circuit suitable for high-end video processing applications, such as HDTV. Silicon design studies indicate that circuits based on this approach incur only a relatively small penalty in terms of power dissipation and silicon area when compared with implementations for specific standards. Indeed, the cost/performance achieved exceeds that of existing but specific solutions and greatly exceeds that of general purpose field programmable gate array (FPGA) designs.

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AIMS/HYPOTHESIS: To determine if vaccinations and infections are associated with the subsequent risk of Type I (insulin-dependent) diabetes mellitus in childhood. METHOD: Seven centres in Europe with access to population-based registers of children with Type I diabetes diagnosed under 15 years of age participated in a case-control study of environmental risk factors. Control children were chosen at random in each centre either from population registers or from schools and policlinics. Data on maternal and neonatal infections, common childhood infections and vaccinations were obtained for 900 cases and 2302 control children from hospital and clinic records and from parental responses to a questionnaire or interview. RESULTS: Infections early in the child's life noted in the hospital record were found to be associated with an increased risk of diabetes, although the odds ratio of 1.61 (95% confidence limits 1.11, 2.33) was significant only after adjustment for confounding variables. None of the common childhood infectious diseases was found to be associated with diabetes and neither was there evidence that any common childhood vaccination modified the risk of diabetes. Pre-school day-care attendance, a proxy measure for total infectious disease exposure in early childhood, was found, however, to be inversely associated with diabetes, with a pooled odds ratio of 0.59 (95% confidence limits 0.46, 0.76) after adjustment for confounding variables. CONCLUSION/INTERPRETATION: It seems likely that the explanation for these contrasting findings of an increased risk associated with perinatal infections coupled with a protective effect of pre-school day care lies in the age-dependent modifying influence of infections on the developing immune system.

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Venom has only been recently discovered to be a basal trait of the Anguimorpha lizards. Consequently, very little is known about the timings of toxin recruitment events, venom protein molecular evolution, or even the relative physical diversifications of the venom system itself. A multidisciplinary approach was used to examine the evolution across the full taxonomical range of this similar to 130 million-year-old clade. Analysis of cDNA libraries revealed complex venom transcriptomes. Most notably, three new cardioactive peptide toxin types were discovered (celestoxin, cholecystokinin, and YY peptides). The latter two represent additional examples of convergent use of genes in toxic arsenals, both having previously been documented as components of frog skin defensive chemical secretions. Two other novel venom gland-overexpressed modified versions of other protein frameworks were also recovered from the libraries (epididymal secretory protein and ribonuclease). Lectin, hyaluronidase, and veficolin toxin types were sequenced for the first time from lizard venoms and shown to be homologous to the snake venom forms. In contrast, phylogenetic analyses demonstrated that the lizard natriuretic peptide toxins were recruited independently of the form in snake venoms. The de novo evolution of helokinestatin peptide toxin encoding do-mains within the lizard venom natriuretic gene was revealed to be exclusive to the helodermatid/anguid subclade. New isoforms were sequenced for cysteine-rich secretory protein, kallikrein, and phospholipase A 2 toxins. Venom gland morphological analysis revealed extensive evolutionary tinkering. Anguid glands are characterized by thin capsules and mixed glands, serous at the bottom of the lobule and mucous toward the apex. Twice, independently this arrangement was segregated into specialized serous protein-secreting glands with thick capsules with the mucous lobules now distinct (Heloderma and the Lanthanotus/Varanus clade). The results obtained highlight the importance of utilizing evolution-based search strategies for biodiscovery and emphasize the largely untapped drug design and development potential of lizard venoms. Molecular & Cellular Proteomics 9:2369-2390, 2010.

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Fibroblast activation protein-a (FAP-a) promotes tumor growth and cell invasiveness through extracellular matrix degradation. How ultraviolet radiation (UVR), the major risk factor for malignant melanoma, influences the expression of FAP-a is unknown. We examined the effect of UVR on FAP-a expression in melanocytes, keratinocytes and fibroblasts from the skin and in melanoma cells. UVR induces upregulation of FAP-a in fibroblasts, melanocytes and primary melanoma cells (PM) whereas keratinocytes and metastatic melanoma cells remained FAP-a negative. UVA and UVB stimulated FAP-a-driven migration and invasion in fibroblasts, melanocytes and PM. In co-culture systems UVR of melanocytes, PM and cells from regional metastases upregulated FAP-a in fibroblasts but only supernatants from non-irradiated PM were able to induce FAP-a in fibroblasts. Further, UV-radiated melanocytes and PM significantly increased FAP-a expression in fibroblasts through secretory crosstalk via Wnt5a, PDGF-BB and TGF-ß1. Moreover, UV radiated melanocytes and PM increased collagen I invasion and migration of fibroblasts. The FAP-a/DPPIV inhibitor Gly-ProP(OPh)2 significantly decreased this response implicating FAP-a/DPPIV as an important protein complex in cell migration and invasion. These experiments suggest a functional association between UVR and FAP-a expression in fibroblasts, melanocytes and melanoma cells implicating that UVR of malignant melanoma converts fibroblasts into FAP-a expressing and ECM degrading fibroblasts thus facilitating invasion and migration. The secretory crosstalk between melanoma and tumor surrounding fibroblasts is mediated via PDGF-BB, TGF-ß1 and Wnt5a and these factors should be evaluated as targets to reduce FAP-a activity and prevent early melanoma dissemination.

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Objective. The authors examined bidirectional relations between youth exposure to sectarian and nonsectarian antisocial behavior and mothers' efforts to control youths' exposure to community violence in Belfast, Northern Ireland. Design. Mother-child dyads (N = 773) were interviewed in their homes twice over 2 years regarding youths' exposure to sectarian and nonsectarian community antisocial behavior and mothers' use of control strategies, including behavioral and psychological control. Results. Youths' exposure to nonsectarian antisocial behavior was related to increases in mothers' use of behavioral and psychological control strategies over time, controlling for earlier levels of these constructs. Reflecting bidirectional relations, mothers' behavioral control strategies were associated with youths' reduced exposure to nonsectarian and sectarian antisocial behavior over time, whereas psychological control was not related to reduced exposure. Conclusion. Only nonsectarian community violence was associated longitudinally with mothers' increased use of control strategies, and only behavioral control strategies were effective in reducing youths' exposure to community antisocial behavior, including sectarian and nonsectarian antisocial behavior.

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Constructed wetland systems (CWS) have been used as a low cost bio-filtration system to treat farm wastewater. While studies have shown that CWS are efficient in removing organic compounds and pathogens, there is limited data on the presence of hormones in this type of treatment system. The objective of this study was to evaluate the ability of the CWS to reduce estrogenic and androgenic hormone concentration in dairy wastewater. This was achieved through a year long study on dairy wastewater samples obtained froma surface flow CWS. Analysis of hormonal levels was performed using a solid phase extraction (SPE) sample clean-up method, combined with reporter gene assays (RGAs) which incorporate relevant receptors capable of measuring total estrogenic or androgenic concentrations as low as 0.24 ng L1 and 6.9 ng L1 respectively. Monthly analysis showed a mean removal efficiency for estrogens of 95.2%, corresponding to an average residual concentration of 3.2 ng L1 17b-estradiol equivalent (EEQ), below the proposed lowest observable effect concentration (LOEC) of 10 ng L1. However, for one month a peak EEQ concentration of 115 ng L1 was only reduced to 18.8 ng L1. The mean androgenic activity peaked at 360 ng L1 and a removal efficiency of 92.1% left an average residual concentration of 32.3 ng L1 testosterone equivalent (TEQ). The results obtained demonstrate that this type of CWS is an efficient system for the treatment of hormones in dairy wastewater. However, additional design improvements may be required to further enhance removal efficiency of peak hormone concentrations.

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We report the discovery of WASP-34b, a sub-Jupiter-mass exoplanet transiting its 10.4-magnitude solar-type host star (1SWASP J110135.89-235138.4; TYC 6636-540-1) every 4.3177 days in a slightly eccentric orbit (e = 0.038±0.012). We find a planetary mass of 0.59±0.01 MJup and radius of 1.22-0.08+0.11 RJup. There is a linear trend in the radial velocities of 55±4 m s-1 y-1 indicating the presence of a long-period third body in the system with a mass ?0.45 MJup at a distance of ?1.2 AU from the host star. This third-body is either a low-mass star, a white dwarf, or another planet. The transit depth ((RP/Rstar)2 = 0.0126) and high impact parameter (b = 0.90) suggest that this could be the first known transiting exoplanet expected to undergo grazing transits, but with a confidence of only 80%. Radial velocity and photometric data are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/526/A130

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The performance of the surface zone of concrete is acknowledged as a major factor governing the rate of deterioration of reinforced concrete structures as it provides the only barrier to the ingress of water containing dissolved ionic species such as chlorides which, ultimately, initiate corrosion of the reinforcement. In-situ monitoring of cover-zone concrete is therefore critical in attempting to make realistic predictions as to the in-service performance of the structure. To this end, this paper presents developments in a remote interrogation system to allow continuous, real-time monitoring of the cover-zone concrete from an office setting. Use is made of a multi-electrode array embedded within cover-zone concrete to acquire discretized electrical resistivity and temperature measurements, with both parameters monitored spatially and temporally. On-site instrumentation, which allows remote interrogation of concrete samples placed at a marine exposure site, is detailed, together with data handling and processing procedures. Site-measurements highlight the influence of temperature on electrical resistivity and an Arrhenius-based temperature correction protocol is developed using on-site measurements to standardize resistivity data to a reference temperature; this is an advancement over the use of laboratory-based procedures. The testing methodology and interrogation system represents a robust, low-cost and high-value technique which could be deployed for intelligent monitoring of reinforced concrete structures.

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Recent societal acceptance of cannabinoids as recreational and therapeutic drugs has posed a potential hazard to male reproductive health. Mammals have a highly sophisticated endogenous cannabinoid (ECS) system that regulates male (and female) reproduction and exo-cannabinoids may influence it adversely. Therefore it is imperative to determine their effects on male reproduction so that men can make informed choices as to their use. Here, an animal model was used to administer HU210, a synthetic analogue of ?9-tetrahydrocannabinol (THC) and potent cannabinoid receptor (CB) agonist to determine its effects on reproductive organ weights, spermatogenesis, testicular histology and sperm motility. Its effects on the physiological endocannabinoid system were also investigated. Spermatogenesis was markedly impaired with reductions in total sperm count after 2 weeks of exposure. Spermatogenic efficiency was depleted, and Sertoli cell number decreased as exposure time increased with seminiferous tubules showing germ cell depletion developing into atrophy in some cases. Sperm motility was also adversely affected with marked reductions from 2 weeks on. HU210 also acted on the sperm’s endocannabinoid system. Long term use of exo-cannabinoids has adverse effects on both spermatogenesis and sperm function. These findings highlight the urgent need for studies evaluating the fertility potential of male recreational drug users.

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The photobleaching of methylene blue MB, sensitised by TiO2, in an aqueous solution is studied in the absence and presence of oxygen, in the absence of oxygen and in the presence of a sacrificial electron acceptor (SED), MB is photoreduced to its colourless leuco form, LMB, by the TiO2 photocatalyst. This same photoreduction process is observed even if an SED is not present, indicating that MB itself can act as an SED. The oxidation of LMB by oxygen to regenerate MB is significantly slower if the aqueous solution is acidified (0.01 mol dm(-3) HClO4) and, at low partial pressures, the rate of reaction depends directly upon the concentration of dissolved oxygen. The TiO2-sensitised photobleaching of MB is irreversible in an oxygen-saturated aqueous solution, as expected, since the bleaching was due to an oxidative process. However, in an acidified solution (0.01 mol dm(-3) HClO4), the photobleaching process, in an oxygen-saturated solution, generates LMB initially. The latter situation arises because, under acidic conditions, LMB reacts only very slowly with oxygen to form MB. The significance of these findings with respect to the popular use of photobleaching of MB as a demonstration of semiconductor photomineralisation is discussed. (C) 1999 Elsevier Science S.A. All rights reserved.

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The pH-dependent fluorescence behavior of two regioisomeric 'receptor(1)-spacer(1)-fluorophore-spacer(2)-receptor(2)' systems 1 and 2 in micellar solutions of sodium dodecyl sulfate show that photoinduced electron transfer (PET) only occurs from the amine group connected to the 4-amino position of the aminonaphthalimide fluorophore in both cases. This demonstrates the directing influence of the photogenerated electric field within the aminonaphthalimide excited state on the electron transfer process. Since path-selectivity of PET is also known within the membrane-bound photosynthetic reaction center in bacteria, its origins may be illuminated by the simple experiments described here. (C) 2011 Elsevier B. V. All rights reserved.

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Recombinant wild-type beta(1) gamma(1) dimers of signal-transducing guanine nucleotide-binding proteins (G proteins) and beta(1) gamma 1 dimers carrying a mutation known to block gamma-subunit isoprenylation (beta(1) gamma(1)C71S) were expressed in baculovirus-infected insect cells. Both wild-type and mutant beta(1) gamma(1) dimers were found in soluble fractions of infected cells upon subcellular fractionation. Anion exchange chromatographic and metabolic-radiolabeling studies revealed that the soluble beta(1) gamma(1) preparation contained approximately equal amounts of non-isoprenylated and isoprenylated beta(1) gamma(1) dimers. Soluble wild-type and mutant beta(1) gamma(1) dimers and native beta(1) gamma(1) dimers purified from bovine retina were reconstituted with recombinant phospholipase C-beta(2). Only isoprenylated beta(1) gamma(1) dimers were capable of stimulating phospholipase C-beta(2). The results show that gamma-subunit isoprenylation and/or additional post-translational processing of the protein are required for beta gamma subunit stimulation of phospholipase C.

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The localization and distribution of SALMFamide immunoreactivity (IR), SI(GFNSALMFamide), in the nervous system of both the adult and larval stages of the trematode Schistosoma mansoni has been determined by an indirect immunofluorescent technique in conjunction with confocal scanning laser microscopy (CSLM). Immunostaining was widespread in the nervous system of adult male and female S. mansoni. In the central nervous system (CNS), IR was evident in nerve cells and fibres in the anterior ganglia, cerebral commissure and dorsal and ventral nerve cords. In the peripheral nervous system (PNS), IR was apparent in nerve plexuses associated with the subtegmental musculature, oral and ventral suckers, the lining of the gynaecophoric canal, and in fine nerve fibres innervating the dorsal tubercles of the male worm. In the reproductive system of male and female worms, S1-IR was only observed around the ootype/Mehlis' gland complex in the female. Immunostaining was also evident in the nervous system of both miracidium and cercarial larval stages. A post-embedding, IgG-conjugated colloidal gold immunostaining technique was employed to examine the subcellular distribution of SALMFamide-IR in the CNS of S. mansoni. Gold labelling of peptide was localized over dense-cored vesicles within nerve cell bodies and fibres constituting the neuropile of the anterior ganglia, cerebral commissure and nerve cords of the CNS. Antigen pre-absorption studies indicated that the results obtained do suggest S1-like immunostaining and not cross-reactivity with other peptides, in particular FMRFamide.

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The localization and distribution of neuropeptides and an indoleamine (serotonin or 5-hydroxytryptamine) in the enteric nervous system (ENS) of the pig roundworm, Ascaris suum, have been determined by the application of an indirect immunofluorescence technique in conjunction with confocal scanning laser microscopy. Whole-mount preparations of pharyngeal, intestinal and rectal regions were screened with antisera to 23 vertebrate peptides, 2 invertebrate peptides and serotonin(= 5-HT). Positive immunoreactivity (IR) was obtained with antisera to pancreatic polypeptide (PP), peptide YY (PYY), FMRFamide, gastrin and serotonin. The only IR observed in the ENS was that evident in the nerve supply to the pharynx and rectal region; no IR was associated with any region of the intestine. The most extensive patterns of IR occurred with antisera to PW, FMRFamide and serotonin. In the pharyngeal component of the ENS, IR was evident in the lateral and dorsal longitudinal pharyngeal nerves, pharyngeal commissures, nerve plexus, and associated nerve cells and fibres. In contrast, the distribution of IR to the PP and gastrin antisera was more restricted and displayed a lower intensity of immunostaining. The other component of the ENS, the rectal enteric system, only yielded immunostaining to FMRFamide. The possible role of neuropeptides and serotonin in the nutritional biology of nematodes is discussed.

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The localisation and distribution of neuropeptides in the peripheral nervous system of the pig roundworm Ascaris suum have been determined by an indirect immunofluorescence technique in conjunction with confocal microscopy. Of the 31 antisera tested, immunostaining was obtained only with antisera to peptide YY (PYY), pancreatic polypeptide (PP) and FMRFamide. Immunostaining for PYY and FMRFamide was evident in the amphidial and papillary ganglia associated with the anterior nerve ring and in the nerves from these ganglia that terminated in sensory receptors within the buccal lips of the parasite. The only peptide immunoreactivity (IR) observed in the reproductive system of either sex was that evident in the nerve supply to the distal region of the vagina in the female worm. It took the form of a well-developed plexus of parallel nerve fibres, cross-connectives and looped commissures. The nerve net diminished in the more proximal region of the vagina. PP-IR was less intense than that for PYY and FMRFamide and was more restricted in distribution, being confined to a small number of nerve fibres in the nerve supply to the vagina; it did not occur in the nerves supplying the anterior sensory receptors. The possible roles of neuropeptides in the sensory and reproductive biology of nematodes are discussed.