966 resultados para Banks and banking, Central
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(Ultrastructure of secretory and senescence phase in colleters of Bathysa gymnocarpa and B. stipulata (Rubiaceae)). Colleters are secretory structures formed by a parenchymatic axis with vascular bundles, bound by a layer of secretory palisade-like epidermis. Some studies regarding the structure of colleters have focused on secretory cells structure, but not distinguished the secretory and senescent phases. Generally, in mucilage-secreting cells such as colleters, the endoplasmic reticulum and Golgi apparatus are involved in secretion production and transport. In these study, colleters structure of Bathysa gymnocarpa K. Schum. and B. stipulata (Vell.) C. Presl. (Rubiaceae) were determined in two phases: a secretory phase and a senescence one. Samples were collected and processed by usual light and electron microscopy techniques. Studied colleters are constituted by an epidermal palisade layer and a central axis formed by parenchymatic cells with rare vascular traces. During the secretory phase, epidermal cells presented a dense cytoplasm, small vacuoles, enhanced rough and smooth endoplasmic reticulum, and a Golgi apparatus close to large vesicles. During the senescence phase epidermal cells presented a disorganized membrane system. No intact organelles or vesicles were observed. The outer cell wall exhibited similar layers to that observed during the secretory phase. The senescent phase is easily defined by the morphology of the colleters, but not well defined at subcellular level. Our research suggests that programmed cell death starts on secretory phase. However, more evidences are needed to evaluate the phenomena.
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The maintenance of arterial pressure at levels adequate to perfuse the tissues is a basic requirement for the constancy of the internal environment and survival. The objective of the present review was to provide information about the basic reflex mechanisms that are responsible for the moment-to-moment regulation of the cardiovascular system. We demonstrate that this control is largely provided by the action of arterial and non-arterial reflexes that detect and correct changes in arterial pressure (baroreflex), blood volume or chemical composition (mechano- and chemosensitive cardiopulmonary reflexes), and changes in blood-gas composition (chemoreceptor reflex). The importance of the integration of these cardiovascular reflexes is well understood and it is clear that processing mainly occurs in the nucleus tractus solitarii, although the mechanism is poorly understood. There are several indications that the interactions of baroreflex, chemoreflex and Bezold-Jarisch reflex inputs, and the central nervous system control the activity of autonomic preganglionic neurons through parallel afferent and efferent pathways to achieve cardiovascular homeostasis. It is surprising that so little appears in the literature about the integration of these neural reflexes in cardiovascular function. Thus, our purpose was to review the interplay between peripheral neural reflex mechanisms of arterial blood pressure and blood volume regulation in physiological and pathophysiological states. Special emphasis is placed on the experimental model of arterial hypertension induced by N-nitro-L-arginine methyl ester (L-NAME) in which the interplay of these three reflexes is demonstrable
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Centromere function requires the proper coordination of several subfunctions, such as kinetochore assembly, sister chromatid cohesion, binding of kinetochore microtubules, orientation of sister kinetochores to opposite spindle poles, and their movement towards the spindle poles. Centromere structure appears to be organized in different, separable domains in order to accomplish these functions. Despite the conserved nature of centromere functions, the molecular genetic definition of the DNA sequences that form a centromere in the yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe, in the fruit fly Drosophila melanogaster, and in humans has revealed little conservation at the level of centromere DNA sequences. Also at the protein level few centromere proteins are conserved in all of these four organisms and many are unique to the different organisms. The recent analysis of the centromere structure in the yeast S. pombe by electron microscopy and detailed immunofluorescence microscopy of Drosophila centromeres have brought to light striking similarities at the overall structural level between these centromeres and the human centromere. The structural organization of the centromere is generally multilayered with a heterochromatin domain and a central core/inner plate region, which harbors the outer plate structures of the kinetochore. It is becoming increasingly clear that the key factors for assembly and function of the centromere structure are the specialized histones and modified histones which are present in the centromeric heterochromatin and in the chromatin of the central core. Thus, despite the differences in the DNA sequences and the proteins that define a centromere, there is an overall structural similarity between centromeres in evolutionarily diverse eukaryotes.
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The distribution, morphology and morphometry of microglial cells in the chick cerebral hemispheres from embryonic day 4 (E4) to the first neonatal day (P1) were studied by histochemical labeling with a tomato (Lycopersicon esculentum) lectin. The histochemical analysis revealed lectin-reactive cells in the nervous parenchyma on day E4. Between E4 (5.7 ± 1.35 mm length) and E17 (8.25 ± 1.2 mm length), the lectin-reactive cells were identified as ameboid microglia and observed starting from the subventricular layer, distributed throughout the mantle layer and in the proximity of the blood vessels. After day E13, the lectin-reactive cells exhibited elongated forms with small branched processes, and were considered primitive ramified microglia. Later, between E18 (5.85 ± 1.5 mm cell body length) and P1 (3.25 ± 0.6 mm cell body length), cells with more elongated branched processes were observed, constituting the ramified microglia. Our findings provide additional information on the migration and differentiation of microglial cells, whose ramified form is observed at the end of embryonic development. The present paper focused on the arrangement of microglial cells in developing cerebral hemispheres of embryonic and neonatal chicks, which are little studied in the literature. Details of morphology, morphometry and spatial distribution of microglial cells contributed to the understanding of bird and mammal central nervous system ontogeny. Furthermore, the identification and localization of microglial cells during the normal development could be used as a morphological guide for embryonic brain injury researches.
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This thesis studies the impact of the latest Russian crisis on global markets, and especially Central and Eastern Europe. The results are compared to other shocks and crises over the last twenty years to see how significant they have been. The cointegration process of Central and Eastern European financial markets is also reviewed and updated. Using three separate conditional correlation GARCH models, the latest crisis is not found to have initiated similar surges in conditional correlations to previous crises over the last two decades. Market cointegration for Central and Eastern Europe is found to have stalled somewhat after initial correlation increases post EU accession.
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In this work, the effects of thermoplastic extrusion process parameters (raw material moisture content and temperature) and the addition of functional ingredients (lycopene and soy protein) on quality characteristics of a base-formulation for extruded corn snacks were studied, with the objective of developing an easy-to-eat functional product. A single-screw Labor PQ 30 model Inbramaq extruder was used for extrusion and a central composite rotational design (CCRD) was followed. The independent variables were: i) percentage of soy protein isolate (0-30%); ii) percentage of lycopene preparation (0-0.1%); iii) raw material moisture content (20-30%); and iv) 5th zone temperature (100-150 °C). The expansion index reached maximum values with the lowest raw material moisture content (20%) and intermediate temperatures (approximately 125 °C). Instrumental hardness was higher with high moisture and low temperature; however, increasing the percentage of soy protein was beneficial for the texture of the product, reducing hardness. The red color intensity increased with the increase in lycopene content and moisture, and with the reduction of temperature. Sensory acceptance tests were carried out for two products, with maximum percentages of the functional ingredients, 20% moisture and temperatures of 125 and 137 °C, with greater acceptance for the product extruded at 125 °C.
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The present study was focused on the analysis of agronomical, nutritional, physicochemical, and antioxidant properties of six genetically different quinoa (Chenopodium quinoa Willd) genotypes cultivated in three distinctive geographical zones of Chile. Ancovinto and Cancosa genotypes from the northern Altiplano (19 ºS), Cáhuil and Faro from the central region (34 ºS), and Regalona and Villarica from the southern region (39 ºS) are representative of high genetic differentiation among the pooled samples, in particular between Altiplano and the central-southern groups. A Common-Garden Assay at 30 ºS showed significant differences among seed origins in all morphometric parameters and also in yields. Altiplano genotypes had larger panicule length but no seed production. A significant influence of the different quinoa genotypes on chemical composition and functional properties was also observed. Protein concentration ranged from 11.13 to 16.18 g.100 g-1 d.m., while total dietary fiber content ranged from 8.07-12.08 g.100 g-1 d.m., and both were the highest in Villarrica ecotype. An adequate balance of essential amino acids was also observed. Sucrose was the predominant sugar in all genotypes. Antioxidant activity was high in all genotypes, and it was highest in Faro genotype (79.58% inhibition).
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This study aimed to define the process conditions to obtain snacks from the by-products of rice and soybean with physical characteristics suitable for marketing. Therefore, the effects of moisture and extrusion temperature on the expansion and color of the products obtained experimentally obtained were evaluated, and the proximate composition of the by-products and that of the snack with greater desirability were determined. Response surface methodology and rotational central composite design were used, and desirability test based on the regression models adjusted was applied. The most desirable snack, with the highest expansion index (3.39), specific volume (13.5 mL.g-1), and the chromaticity coordinate a* (2.79), was obtained under 12 g.100 g-1 moisture and 85ºC of temperature in the third zone of the extruder. The snack produced under these conditions attained content of protein and lipid content 41 and 64% higher than that of the traditional corn snack. It can be concluded that producing extruded snack made form a mixture of broken grains, rice bran, and soybean okara (81:9:10) is technologically feasible, enabling the development of a new product with good nutritional value that can improve the diet of children, the main consumers of this type of food.
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Financial industry has recently encountered many changes in the business environment. Increased regulation together with growing competition is forcing commercial banks to rethink their business models. In order to maintain profitability in the new environment, banks are focusing more into activities that yield noninterest income. This is a shift away from the traditional intermediation function of banks. This study aims to answer the question if the shift from traditional income yielding activities to more innovative noninterest activities is logical in terms of profitability and risk in Nordics. This study also aims to answer the question if diversification within the noninterest income categories has impact on profitability and risk and if there are certain categories of noninterest income that are better than others in terms of profitability and risk in Nordics. Results show that diversification between interest and noninterest activities and increase in the share of noninterest income have a negative impact on the risk adjusted returns and risk profile. Results also show that further diversification within the noninterest income categories has negative impact on risk adjusted profitability and risk while an increase of the share of commission and fee income category of total noninterest income has a positive impact on risk adjusted profitability and risk. Results are logical and in line with previous research (De Young & Roland, 2001; Stiroh, 2004). Results provide useful information to banks and help them better evaluate outcomes of different income diversification strategies.
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To evaluate the Greenspan era, we nevertheless need to address three questions: Is his success due to talent or just luck? Does he have a system of monetary policy or is he himself the system? What will be his legacy? Greenspan was certainly lucky, but he was also clairvoyant. Above all, he has developed a profoundly original monetary policy. His confidence strategy is clearly opposed to the credibility strategy developed in central banks and the academic milieu after 1980, but also inflation targeting, which today constitutes the mainstream monetary policy regime. The question of his legacy seems more nuanced. However, Greenspan will remain 'for a considerable period of time' a highly heterodox and original central banker. His political vision, his perception of an uncertain world, his pragmatism and his openness form the structure of a powerful alternative system, the confidence strategy, which will leave its mark on the history of monetary policy.
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The impact of ventricular rate (VR) on the outcome of electrical cardioversion (ECV) of acute atrial fibrillation (AF) is currently unknown. We aimed to determine the effect of VR during acute AF on the success of ECV, recurrence of AF and occurrence of post-cardioversion complications in 30 days follow-up. All ECVs performed in patients with acute atrial fibrillation lasting <48 hours in 2 Finnish university hospitals during 2003-2010 and 1 central hospital during 2010 were retrospectively identified. A total of 6,624 ECVs were performed in 2,821 consecutive patients. VR≤60 BPM was defined low and VR≥160 BPM high. The median VR before ECV was 109 BPM. The success rate of ECV was 94.2%. Bradycardia occurred in 62 (0.9%) and thromboembolic complications in 39 (0.6%) ECVs. Low VR was observed before 75 (1.1%) ECVs and male sex was its only independent predictor. High VR was observed in 165 (2.5%) ECVs. The independent predictors of high VR were younger age, <12 h episode duration, no previous history of AF and alcohol abuse. Low or high VR were not related to the success of ECV, incidence of thromboembolic or bradycardic complications, or recurrence of AF, although VR was significantly (p<0.001) lower in the patients in whom AF recurred. In conclusion, ECV of acute AF is an effective procedure and VR during AF does not affect its efficacy, the maintenance of sinus rhythm or the incidence of bradycardic, thromboembolic or other complications during 30 days follow-up after ECV. Low VR is predominately observed in male patients, while high VR was a feature related to a shorter history of AF and high alcohol-intake.
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Tämän kandidaatintutkielman tarkoituksena on tutkia, miten lohkoketjuteknologiaa voi soveltaa finanssisektorille. Tutkimus tarjoaa yleiskuvan lohkoketjuteknologista, sekä sen sovelluskohteista finanssisektorilla. Tutkimusmenetelmä on kvalitatiivinen ja se toteutettiin haastattelemalla pankkeja, jotka osallistuvat Distributed Ledger Group (DLG)-konsortioon. Kyseinen konsortio pyrkii 42 pankin ja R3cev nimisen yrityksen välisessä yhteistyössä soveltamaan lohkoketjuteknologiaa pankkisektorille. Haastattelujen perusteella pankit pitävät lohkoketjuteknologian potentiaalia pitkällä aikavälillä suurena. Erityisesti lohkoketjuteknologian odotetaan laskevan kustannuksia, sekä nopeuttavan toimintoja useiden eri tuotteiden kohdalla. Pelkästään pankkisektorilla tutkitaan tällä hetkellä kymmeniä eri sovelluskohteita. Ennen kuin lohkoketjulla voidaan nähdä kaupallista toimintaa, tulee haasteita ylittää sekä teknisellä, että säädännöllisellä puolella. Vielä on liian varhaista arvioida, milloin lohkoketjuteknologiaa tullaan soveltamaan laajemmin finanssisektorilla. Pankkien oma tutkimus aiheesta oli vielä suhteellisen varhaisessa vaiheessa. Lohkoketjuteknologian potentiaali voidaan nähdä tutkimuksen perusteella valtavan suurena. Vielä on kuitenkin vaikea arvioida tullaanko tähän potentiaaliin tulevaisuudessa yltämään. Finanssisektorilla on monia toimijoita, jotka tutkivat lohkoketjuteknologiaa ja se vauhdittaa kehitystä. Lohkoketjuteknologia saattaa tulevaisuudessa mullistaa monia finanssisektorin osa-alueita tai jopa korvata ne kokonaan.
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During the Upper Cambrian there were three mass extinctions, each of which eliminated at least half of the trilobite families living in North American shelf seas. The Nolichucky Formation preserves the record of one of these extinction events at the base of the Steptoean Stage. Sixty-six trilobite collections were made from five sections In Tennessee and Virginia. The lower Steptoean faunas are assigned to one low diversity, Aphelaspis-dominated biofacies, which can be recognized in several other parts of North America. In Tennessee, the underlying upper Marjuman strata contain two higher diversity biofacies, the Coosella-Glaphyraspis Biofacies and the Tricrepicephalus-Norwoodiid Biofacies. At least four different biofacies are present in other parts of North America: the Crepicephalus -Lonchocephalus Biofacies, the Kingstonia Biofacies, the Cedaria Biofacies, and the Uncaspis Biofacies. A new, species-based zonation for the Nolichucky Formation imcludes five zones, three of which are new. These zones are the Crepicephalus Zone, the Coosella perplexa Zone, the Aphelaspis buttsi Zone, the A. walcotti Zone and the A. tarda Zone. The Nolichucky Formation was deposited within a shallow shelf basin and consists largely of subtidal shales with stormgenerated carbonate interbeds. A relative deepening is recorded In the Nolichucky Formation near the extinction, and is indicated In some sections by the appearance of shale-rich, distal storm deposits above a carbonate-rich, more proximal storm deposit sequence. A comparable deepening-upward sequence occurs near the extinction in the Great Basin of southwestern United States and in central Texas, and this suggests a possible eustatic control. In other parts of North America, the extinction IS recorded In a variety of environmental settings that range from near-shore to slope. In shelf environments, there is a marked decrease in diversity, and a sharp reduction in biofacies differentiation. Although extinctions do take place in slope environments, there IS no net reduction in diversity because of the immigration of several new taxa.
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Both learning and basic biological mechanisms have been shown to play a role in the control of protein int^e. It has previously been shown that rats can adapt their dietary selection patterns successfully in the face of changing macronutrient requirements and availability. In particular, it has been demonstrated that when access to dietary protein is restricted for a period of time, rats selectively increase their consumption of a proteincontaining diet when it becomes available. Furthermore, it has been shown that animals are able to associate various orosensory cues with a food's nutrient content. In addition to the role that learning plays in food intake, there are also various biological mechanisms that have been shown to be involved in the control of feeding behaviour. Numerous studies have documented that various hormones and neurotransmitter substances mediate food intake. One such hormone is growth hormone-releasing factor (GRF), a peptide that induces the release of growth hormone (GH) from the anterior pituitary gland. Recent research by Vaccarino and Dickson ( 1 994) suggests that GRF may stimulate food intake by acting as a neurotransmitter in the suprachiasmatic nucleus (SCN) and the adjacent medial preoptic area (MPOA). In particular, when GRF is injected directly into the SCN/MPOA, it has been shown to selectively enhance the intake of protein in both fooddeprived and sated rats. Thus, GRF may play a role in activating protein consumption generally, and when animals have a need for protein, GRF may serve to trigger proteinseeking behaviour. Although researchers have separately examined the role of learning and the central mechanisms involved in the control of protein selection, no one has yet attempted to bring together these two lines of study. Thus, the purpose of this study is to join these two parallel lines of research in order to further our understanding of mechanisms controlling protein selection. In order to ascertain the combined effects that GRF and learning have on protein intake several hypothesis were examined. One major hypothesis was that rats would successfully alter their dietary selection patterns in response to protein restriction. It was speculated that rats kept on a nutritionally complete maintenance diet (NCMD) would consume equal amount of the intermittently presented high protein conditioning diet (HPCD) and protein-free conditioning diet (PFCD). However, it was hypothesized that rats kept on a protein-free maintenance diet (PFMD) would selectively increase their intake of the HPCD. Another hypothesis was that rats would learn to associate a distinct marker flavour with the nutritional content of the diets. If an animal is able to make the association between a marker flavour and the nutrient content of the food, then it is hypothesized that they will consume more of a mixed diet (equal portion HPCD and PFCD) with the marker flavour that was previously paired with the HPCD (Mixednp-f) when kept on the PFMD. In addition, it was hypothesized that intracranial injection of GRF into the SCN/MPOA would result in a selective increase in HPCD as well as Mixednp-t consumption. Results demonstrated that rats did in fact selectively increase their consumption of the flavoured HPCD and Mixednp-f when kept on the NCMD. These findings indicate that the rats successfully learned about the nutrient content of the conditioning diets and were able to associate a distinct marker flavour with the nutrient content of the diets. However, the results failed to support previous findings that GRF increases protein intake. In contrast, the administration of GRF significantly reduced consumption of HPCD during the first hour of testing as compared to the no injection condition. In addition, no differences in the intake of the HPCD were found between the GRF and vehicle condition. Because GRF did not selectively increase HPCD consumption, it was not surprising that GRF also did not increase MixedHP-rintake. What was interesting was that administration of GRF and vehicle did not reduc^Mixednp-f consumption as it had decreased HPCD consumption.
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Flavour is a combination of taste, odour, and chemesthetic sensations. Close associations exist between these sensory modalities, and thus, the overall flavour of a food or beverage product can change when the intensity of one or more of these sensations is altered. Strategies to modify flavour are often utilized by the food industry, and are central to the engineering of new and reformulated products. For functional food and beverages, flavour modification is particularly important, as fortifying agents can elicit high levels of less than desirable sensations, such as bitterness and astringency. The application of various flavour modifying strategies can decrease the perceived intensity of these sensations, and in tum, improve the sensory profile of the product. This collection of studies describes the sensory characteristics of experimental functional beverages fortified with trans-resveratrol, (+)-catechin, and/or caffeine, and examines the impact of novel flavour modifying strategies on the perceived flavour of these beverages. In the first study, results demonstrate that the flavour profile of Cabemet Sauvignon wines fortified with 20 mglL and 200 mg/L of trans-resveratrol is not perceived as different compared to control wine (0 mglL). However, Riesling wine fortified with 200 mg/L is perceived as significantly higher in bitterness compared to 20 mglL and control. For some functional food formulations, alternative strategies for flavour modification are needed. Traditional methods, such as the addition of sucrose and sodium chloride, may decrease the perceived 'healthiness' of a product, and thus, may be sub-optimal. In a second study, high and low concentrations of five different bitter inhibiting compounds - 'bitter blockers' - (B-cyclodextrin, homoeridictyol sodium salt, carboxymethylcellulose - low viscosity, zinc sulfate, magnesium sulfate) were tested for their efficacy towards decreasing the bitterness of high and low concentrations of caffeine and (+)catechin - two health-relevant, plant-derived bitterants. B-cyclodextrin and homoeridictyol sodium salt were the most effective blockers at decreasing (+ )-catechin and caffeine, respectively. In addition to bitter blockers, additional flavour modifying strategies, either alone or in combination - may also be successful in functional food formulations. Both sucrose and rebaudioside A - a plant-derived sweetener - were effective at decreasing the bitterness of (+)catechin. When added to (+)-catechin along with B-cyc1odextrin, both sweeteners provided the most effective decrease in bitterness compared to binary, ternary, or quaternary mixtures of (+)catechin together with bitter blockers, sweeteners, andlor odourants. The perceived intensity of sensations elicited by sweeteners and odourants was not affected by the addition of bitter blockers, and thus, their impact within these complex matrices is minimal. In addition, withinmodal (taste-taste) compared to cross-modal (taste-odour) sensory interactions were more effective at decreasing the bitterness of (+ )-catechin. Overall, results from these studies demonstrate that certain novel, alternative flavour modifying approaches may be successful towards lowering the bitterness and astringency elicited by (+ )-catechin and caffeine in aqueous solutions.