881 resultados para centralised separation mangement
Resumo:
Background: Recent morpho-functional evidences pointed out that abnormalities in the thalamus could play a major role in the expression of migraine neurophysiological and clinical correlates. Whether this phenomenon is primary or secondary to its functional disconnection from the brain stem remains to be determined.Aim: We used a Functional Source Separation algorithmof EEG signal to extract the activity of the different neuronal pools recruited at different latencies along the somatosensory pathway in interictal migraine without aura(MO) patients. Method: Twenty MO patients and 20 healthy volunteers(HV) underwent EEG recording. Four ad-hoc functional constraints, two sub-cortical (FS14 at brain stem andFS16 at thalamic level) and two cortical (FS20 radial andFS22 tangential parietal sources), were used to extract the activity of successive stages of somatosensory information processing in response to the separate left and right median nerve electric stimulation. A band-pass digital filter (450–750 Hz) was applied offline in order to extract high-frequency oscillatory (HFO) activity from the broadband EEG signal. Results: In both stimulated sides, significant reduced subcortical brain stem (FS14) and thalamic (FS16) HFO activations characterized MO patients when compared with HV. No difference emerged in the two cortical HFO activations between two groups. Conclusion: Present results are the first neurophysiological evidence supporting the hypothesis that a functional disconnection of the thalamus from the subcortical monoaminergicsystem may underline the interictal cortical abnormal information processing in migraine. Further studiesare needed to investigate the precise directional connectivity across the entire primary subcortical and cortical somatosensory pathway in interictal MO.
Resumo:
Modification of TiO2 with metal oxide nanoclusters such as FeOx, NiOx has been shown to be a promising approach to the design of new photocatalysts with visible light absorption and improved electron–hole separation. To study further the factors that determine the photocatalytic properties of structures of this type, we present in this paper a first principles density functional theory (DFT) investigation of TiO2 rutile(110) and anatase(001) modified with PbO and PbO2 nanoclusters, with Pb2+ and Pb4+ oxidation states. This allows us to unravel the effect of the Pb oxidation state on the photocatalytic properties of PbOx-modified TiO2. The nanoclusters adsorb strongly at all TiO2 surfaces, creating new Pb–O and Ti–O interfacial bonds. Modification with PbO and PbO2 nanoclusters introduces new states in the original band gap of rutile and anatase. However the oxidation state of Pb has a dramatic impact on the nature of the modifications of the band edges of TiO2 and on the electron–hole separation mechanism. PbO nanocluster modification leads to an upwards shift of the valence band which reduces the band gap and upon photoexcitation results in hole localisation on the PbO nanocluster and electron localisation on the surface. By contrast, for PbO2 nanocluster modification the hole will be localised on the TiO2 surface and the electron on the nanocluster, thus giving rise to two different band gap reduction and electron–hole separation mechanisms. We find no crystal structure sensitivity, with both rutile and anatase surfaces showing similar properties upon modification with PbOx. In summary the photocatalytic properties of heterostructures of TiO2 with oxide nanoclusters can be tuned by oxidation state of the modifying metal oxide, with the possibility of a reduced band gap causing visible light activation and a reduction in charge carrier recombination.
Resumo:
Sex workers are members of our communities, whether they are local or national communities. In law, mainstream media representations, and research sex workers are positioned as outside of or in opposition to communities. Even within marginalized communities sex workers are excluded when appeals to respectability politics are made. In this thesis I analyze three analytic sites from three areas of social life. The first chapter performs a textual analysis of The Bedford Decision (2013) and the resulting Protection of Communities and Exploited Persons Act (2014) as an examination of law. The second chapter is an analysis of filmic discourse on community, sex workers, and violence in the mainstream film London Road (2015) as an examination of mainstream media. The third chapter draws upon empirical research, i.e. in-depth interviews with three current and former sex workers in Ottawa, Canada and analyzes the transcripts using interpretative phenomenological analysis (IPA) to center how sex workers’ understanding of their work, community, and the laws and policies that are supposed govern and protect them. In my preface and conclusion I discuss some of the ethical dilemmas I encountered while conducting this research. My findings suggest that sex workers are being positioned and understood as outside of communities in ways that contribute to violence against sex workers. The implications of this research suggest that people who speak in the name of communities—communities in the sense of local neighborhood communities, activist communities, and national communities—need to recognize that sex workers are part of their communities and be accountable to ensuring they are treated as members. Researchers who conduct research on sex work and sex workers need to be accountable to their participants and the impacts their research may have on laws and policies. Sex workers are an over-researched population yet their voices are largely misappropriated or silenced in popular research and policy debates.
Resumo:
Roland Paris is one of those authors whose work is always enjoyable, as he exploits so well the gap between the policy world and academia. His best work reveals a high level of policy insight often before many of his colleagues in academia have caught up. His secret is an ability to analyse the shifting understandings at policy level and to then articulate them in academic terms as if critiquing current policies. This enables his work to be both popular with policy-makers and with their erstwhile critics in academia. His 2004 monograph, At War’s End, captured the shift from peacekeeping intervention and ‘early exit’ to the extended remits of international statebuilding (‘Institutionalization before Liberalization’). It provided a wonderful rationalisation of policy shifts that had already occurred in the late 1990s, starting with the extension of international mandates in Bosnia, from 1996 onwards, and further developed with the Kosovo protectorate in 1999. However, this shift was skilfully reposed as a critique of existing policy-understandings.
Resumo:
This study describes further validation of a previously described Peptide-mediated magnetic separation (PMS)-Phage assay, and its application to test raw cows’ milk for presence of viable Mycobacterium avium subsp. paratuberculosis (MAP). The inclusivity and exclusivity of the PMS-phage assay were initially assessed, before the 50% limit of detection (LOD50) was determined and compared with those of PMS-qPCR (targeting both IS900 and f57) and PMS-culture. These methods were then applied in parallel to test 146 individual milk samples and 22 bulk tank milk samples from Johne’s affected herds. Viable MAP were detected by the PMS-phage assay in 31 (21.2%) of 146 individual milk samples (mean plaque count of 228.1 PFU/50 ml, range 6-948 PFU/50 ml), and 13 (59.1%) of 22 bulk tank milks (mean plaque count of 136.83 PFU/50 ml, range 18-695 PFU/50 ml). In contrast, only 7 (9.1%) of 77 individual milks and 10 (45.4%) of 22 bulk tank milks tested PMS-qPCR positive, and 17 (11.6%) of 146 individual milks and 11 (50%) of 22 bulk tank milks tested PMS-culture positive. The mean 50% limits of detection (LOD50) of the PMS-phage, PMS-IS900 qPCR and PMS-f57 qPCR assays, determined by testing MAP-spiked milk, were 0.93, 135.63 and 297.35 MAP CFU/50 ml milk, respectively. Collectively, these results demonstrate that, in our laboratory, the PMS-phage assay is a sensitive and specific method to quickly detect the presence of viable MAP cells in milk. However, due to its complicated, multi-step nature, the method would not be a suitable MAP screening method for the dairy industry.
Resumo:
Les macrolactones sont des squelettes structuraux importants dans de nombreuses sphères de l’industrie chimique, en particulier dans les marchés pharmaceutiques et cosmétiques. Toutefois, la stratégie traditionnelle pour la préparation de macrolactones demeure incommode en requérant notamment l’ajout (super)stœchiométrique d’agents activateurs. Conséquemment, des quantités stœchiométriques de sous-produits sont générées; ils sont souvent toxiques, dommageables pour l’environnement et nécessitent des méthodes de purification fastidieuses afin de les éliminer. La présente thèse décrit le développement d’une macrolactonisation efficace catalysée au hafnium directement à partir de précurseurs portant un acide carboxylique et un alcool primaire, ne générant que de l’eau comme sous-produit et ne nécessitant pas de techniques d’addition lente et/ou azéotropique. Le protocole a également été adapté à la synthèse directe de macrodiolides à partir de mélanges équimolaires de diols et de diacides carboxyliques et à la synthèse de dimères tête-à-queue de seco acides. Des muscs macrocycliques ainsi que des macrolactones pertinentes à la chimie médicinale ont pu être synthétisés avec l’approche développée. Un protocole pour l’estérification directe catalysée au hafnium entre des acides carboxyliques et des alcools primaires a aussi été développé. Différentes méthodes pour la macrolactonisation catalytique directe entre des alcools secondaires et des acides carboxyliques ont été étudiées. En outre, la stratégie de séparation de phase en macrocyclisation en débit continu a été appliquée lors de la synthèse totale formelle de la macrolactone ivorenolide A. Les étapes-clés de la synthèse incluent une macrocyclisation par le couplage d’alcynes de Glaser-Hay et une réaction de métathèse d’alcènes Z-sélective.
Resumo:
An initial laboratory-scale evaluation of separation characteristics of membranes with nominal molecular weight cut-offs (NMWCO) ranging from 30 kD down to 0.5 kD indicated effective separation of betalains in the 0.5 kD region. Subsequent pilot-level trials using 1 kD, loose reverse osmosis (LRO) and reverse osmosis (RO) spiral-wound membranes showed LRO membrane to be very efficient with up to 96% salt and 47% other dissolved solids removed while retaining majority of the pigment (∼98%) in the betalain rich extract (BRE). The total betalain content in the BRE increased up to 46%, the highest recovery reported so far at pilot scale level. Interestingly, more than 95% of the nitrates were removed from the BRE after the three diafiltrations. These studies indicate that membrane technology is the most efficient technique to produce BRE with highly reduced amounts of salts and nitrate content.
Resumo:
In the primary studying, known leeches have included into free living and parasitic which the parasitic group, besides of direct impacts like: growth detraction, anemia, making wound in the connecting part with the skin, with making plat for secondary bacterial and molding infections in the toll place, is able to cause to transfer blood flagellate and virus to the fish too. Therefore, by accusing information related to fauna leeches of each area a risk factor from the viewpoint of the possibility of being or accusing transferred diseases by these leeches, one can predict and forehand about them. Freshwater leeches of Iran to present accurate recognition (morphological, molecular) have not been, and there are some limited reports from different parts of the country about them. One of the areas that its leeches have not been identified yet is Kurdistan, By having five latrines and big permanent rivers and 32000 springs and a lot of deep and semi-deep wells and this province is a convenient bed for growing aquatics in the country. Therefore, identifying risk factors for development of aquaculture on water resources is one important factor to access achieving development goals. For recognizing leeches of this province, some samples from 10 stands were token. Samples from under stones, sticking to the fish, turtles, plants and solid substances in the water were separated and after recording their physical characteristics, calming with 10% ethylic alcohol with 10% formalin become fixed and after painting with Carmen acetic acid by standard keys for 7 species of Helobdella stagnalis, Placobdella costata, Hemiclepsis marginata, Erpobdella octoculata, Hirudo medicinalis, Dina lineate lineata have been identified and described. Which Helobdella stagnalis has the highest distribution in the province and the minimum one is Hirudo medicinalis. However, that the data obtained in leeches in Kurdistan is a relatively complete collection in this research, recognizing fauna of these areas needs more studying. The Placobdella costata and Hemiclepsis marginata sticking to the fish were separated among identified species which showed that these are parasites for the fish. The sticking area of those leeches to the skin was accompanied with scales cast, damage to mucous membranes beneath the parasite and bleeding Was associated with Histopathology studying effect includes observing break and disconnection in the leech connecting place to the epithelial layer of epidermis in the skin, destroyed nucleus in skin Epithelial cells with observing necrosis in ulcerative place become of the leech and the sub acute inflammated penetration until acute necrosis with opening in Dermis layer is observable. Kidney of this fish have changes such as: proliferation, like proliferative kidney disease with increasing proliferative glomerular cells and increasing in membranous cells in Capillary corpuscle, observing necrotic cells in haematopoietic tissue of kidney along with increasing in infiltration of leukocyte's cells generally mono nucluars such as lymphocytes and less poly morpho nucluars such as neutrophiles that are symptoms of disorders causing anemia become of nourishing and sucking blood by the leech and creating a chronic kidney infection that originally root is in another place like the skin. Also Hemorrhagic anemia causes losing RBC's is because of using the host blood by the leech. (In this situation, one can see immature RBC red cells in Peripheral blood. To identify potential carriers of the leech to the viruses, after finding them in recorded stands and putting them in 75% ethanol for viruses cause IPN, VHS, IHN, they were tested by PCR that the conclusion of these experiments approved IPN virus in Hemiclepsis marginata and Hirudo medicinalis. This kind of leeches can act like a mechanical carrier and causing spreading the agent of this disease. It is worth mentioning that studying the pathogenicity of this virus for aquaculture sources, mentioned before needs more research. During the study of infected fish with leeches that was done after preparing bloody slides and staining them, no case blood parasites was observed. During a research about infecting fish experimentally to known leeches it become clear that 5 days after being in aquarium including leeches, samples of sticking Hirudo medicinalis leech to the golden carp with scales cast were observed. Including leeches to the fish started with molting the scales in the sticking area in the fish and fish become too uneasy and by rubbing themselves to the malls and things inside the aquarium, tried to separate them. Finally, after around 30 hours, leeches penetrate the skin, feeding from blood and tissue liquids and cause mortality the fish and then they become separated from them. If the corpse of these fish stayed in the aquarium, the Helobdella stagnalis and Erpobdella octoculata would start feeding them.
Resumo:
2-Aminothiazole covalently attached to a silica gel surface was prepared in order to obtain an adsorbent for Hg(II) ions having the following characteristics: good sorption capacity, chemical stability under conditions of use, and, especially, high selectivity. The accumulation voltammetry of mercury(II) was investigated at a carbon paste electrode chemically modified with silica gel functionalized with 2-aminothiazole (SIAMT-CPE). The repetitive cyclic voltammogram of mercury(II) solution in the potential range -0.2 to + 0.6 V versus Ag/AgCl (0.02 mol L-1 KNO3; V = 20 mV s(-1)) show two peaks one at about 0.1 V and other at 0.205 V. The anodic wave peak at 0.205 V is well defined and does not change during the cycles and it was therefore further investigated for analytical purposes using differential pulse anodic stripping voltammetry in differents supporting electrolytes. The mercury response was evaluated with respect to pH, electrode composition, preconcentration time, mercury concentration, cleaning solution, possible interferences and other variables. The precision for six determinations (n = 6) of 0.02 and 0.20 mg L-1 Hg(II) was 4.1 and 3.5% (relative standard deviation), respectively. The detection limit was estimated as 0.10 mu g L-1 mercury(II) by means of 3:1 current-to-noise ratio in connection with the optimization of the various parameters involved and using the highest-possible analyser sensitivity. (c) 2006 Elsevier Ltd. All rights reserved.
Resumo:
Agricultural crops can be damaged by funguses, insects, worms and other organisms that cause diseases and decrease the yield of production. The effect of these damaging agents can be reduced using pesticides. Among them, triazole compounds are effective substances against fungus; for example, Oidium. Nevertheless, it has been detected that the residues of these fungicides in foods as well as in derivate products can affect the health of the consumers. Therefore, the European Union has established several regulations fixing the maximum residue of pesticide levels in a wide range of foods trying to assure the consumer safety. Hence, it is very important to develop adequate methods to determine these pesticide compounds. In most cases, gas or liquid chromatographic (GC, LC) separations are used in the analysis of the samples. But firstly, it is necessary to use proper sample treatments in order to preconcentrate and isolate the target analytes. To reach this aim, microextraction techniques are very effective tools; because allow to do both preconcentration and extraction of the analytes in one simple step that considerably reduces the source of errors. With these objectives, two remarkable techniques have been widely used during the last years: solid phase microextraction (SPME) and liquid phase microextraction (LPME) with its different options. Both techniques that avoid the use or reduce the amount of toxic solvents are convenient coupled to chromatographic equipments providing good quantitative results in a wide number of matrices and compounds. In this work simple and reliable methods have been developed using SPME and ultrasound assisted emulsification microextraction (USAEME) coupled to GC or LC for triazole fungicides determination. The proposed methods allow confidently determine triazole concentrations of μg L‐1 order in different fruit samples. Chemometric tools have been used to accomplish successful determinations. Firstly, in the selection and optimization of the variables involved in the microextraction processes; and secondly, to overcome the problems related to the overlapping peaks. Different fractional factorial designs have been used for the screening of the experimental variables; and central composite designs have been carried out to get the best experimental conditions. Trying to solve the overlapping peak problems multivariate calibration methods have been used. Parallel Factor Analysis 2 (PARAFAC2), Multivariate Curve Resolution (MCR) and Parallel Factor Analysis with Linear Dependencies (PARALIND) have been proposed, the adequate algorithms have been used according to data characteristics, and the results have been compared. Because its occurrence in Basque Country and its relevance in the production of cider and txakoli regional wines the grape and apple samples were selected. These crops are often treated with triazole compounds trying to solve the problems caused by the funguses. The peel and pulp from grape and apple, their juices and some commercial products such as musts, juice and cider have been analysed showing the adequacy of the developed methods for the triazole determination in this kind of fruit samples.
Resumo:
This study describes the psychometric properties of the Children's Separation Anxiety Scale (CSAS), which assesses separation anxiety symptoms in childhood. Participants in Study 1 were 1,908 schoolchildren aged between 8 and 11. Exploratory factor analysis identified four factors: worry about separation, distress from separation, opposition to separation, and calm at separation, which explained 46.91% of the variance. In Study 2, 6,016 children aged 8–11 participated. The factor model in Study 1 was validated by confirmatory factor analysis. The internal consistency (α = 0.82) and temporal stability (r = 0.83) of the instrument were good. The convergent and discriminant validity were evaluated by means of correlations with other measures of separation anxiety, childhood anxiety, depression and anger. Sensitivity of the scale was 85% and its specificity, 95%. The results support the reliability and validity of the CSAS.
Resumo:
Les macrolactones sont des squelettes structuraux importants dans de nombreuses sphères de l’industrie chimique, en particulier dans les marchés pharmaceutiques et cosmétiques. Toutefois, la stratégie traditionnelle pour la préparation de macrolactones demeure incommode en requérant notamment l’ajout (super)stœchiométrique d’agents activateurs. Conséquemment, des quantités stœchiométriques de sous-produits sont générées; ils sont souvent toxiques, dommageables pour l’environnement et nécessitent des méthodes de purification fastidieuses afin de les éliminer. La présente thèse décrit le développement d’une macrolactonisation efficace catalysée au hafnium directement à partir de précurseurs portant un acide carboxylique et un alcool primaire, ne générant que de l’eau comme sous-produit et ne nécessitant pas de techniques d’addition lente et/ou azéotropique. Le protocole a également été adapté à la synthèse directe de macrodiolides à partir de mélanges équimolaires de diols et de diacides carboxyliques et à la synthèse de dimères tête-à-queue de seco acides. Des muscs macrocycliques ainsi que des macrolactones pertinentes à la chimie médicinale ont pu être synthétisés avec l’approche développée. Un protocole pour l’estérification directe catalysée au hafnium entre des acides carboxyliques et des alcools primaires a aussi été développé. Différentes méthodes pour la macrolactonisation catalytique directe entre des alcools secondaires et des acides carboxyliques ont été étudiées. En outre, la stratégie de séparation de phase en macrocyclisation en débit continu a été appliquée lors de la synthèse totale formelle de la macrolactone ivorenolide A. Les étapes-clés de la synthèse incluent une macrocyclisation par le couplage d’alcynes de Glaser-Hay et une réaction de métathèse d’alcènes Z-sélective.
Resumo:
In this work, ionic liquids are evaluated for the first time as solvents for extraction and entrainers in separation processes involving terpenes and terpenoids. For that purpose, activity coefficients at infinite dilution, γ13 ∞, of terpenes and terpenoids, in the ionic liquids [C4mim]Cl, [C4mim][CH3SO3], [C4mim][(CH3)2PO4] and [C4mim][CF3SO3] were determined by gas−liquid chromatography at six temperatures in the range 398.15 to 448.15 K. On the basis of the experimental values, a correlation of γ13 ∞ with an increase of the solubility parameters is proposed. The infinite dilution thermodynamic functions were calculated showing the entropic effect is dominant over the enthalpic. Gas−liquid partition coefficients give indications about the recovery and purification of terpenes and terpenoids from ionic liquid solutions. Presenting a strong innovative character, COSMO-RS was evaluated for the description of the selectivities and capacities, showing to be a useful tool for the screening of ionic liquids in order to find suitable candidates for terpenes and terpenoids extraction, and separation. COSMO-RS predictions show that in order to achieve the maximum separation efficiency, polar anions should be used such as bis(2,4,4-trimethylpentyl)phosphinate or acetate, whereas high capacities require nonpolar cations such as phosphonium.