999 resultados para Normal operations


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PURPOSE: Patients with magnetic resonance (MR)-negative focal epilepsy (MRN-E) have less favorable surgical outcomes (between 40% and 70%) compared to those in whom an MRI lesion guides the site of surgical intervention (60-90%). Patients with extratemporal MRN-E have the worst outcome (around 50% chance of seizure freedom). We studied whether electroencephalography (EEG) source imaging (ESI) of interictal epileptic activity can contribute to the identification of the epileptic focus in patients with normal MRI. METHODS: We carried out ESI in 10 operated patients with nonlesional MRI and a postsurgical follow-up of at least 1 year. Five of the 10 patients had extratemporal lobe epilepsy. Evaluation comprised surface and intracranial EEG monitoring of ictal and interictal events, structural MRI, [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET), ictal and interictal perfusion single photon emission computed tomography (SPECT) scans. Eight of the 10 patients also underwent intracranial monitoring. RESULTS: ESI correctly localized the epileptic focus within the resection margins in 8 of 10 patients, 9 of whom experienced favorable postsurgical outcomes. DISCUSSION: The results highlight the diagnostic value of ESI and encourage broadening its application to patients with MRN-E. If the surface EEG contains fairly localized spikes, ESI contributes to the presurgical decision process.

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The distribution of immunoreactivity for the neurofilament triplet class of intermediate filament proteins was examined in the hippocampus of young, adult and elderly control cases and compared to that of Alzheimer's disease cases. In a similar fashion to non-human mammalian species, pyramidal neurons in the CA1 region showed a very low degree of neurofilament triplet immunoreactivity in the three younger control cases examined. However, in the other control cases of 49 years of age and older, many CA1 pyramidal neurons showed elevated neurofilament immunoreactivity. In the Alzheimer's disease cases, most of the surviving CA1 neurons showed intense labeling for the neurofilament triplet proteins, with many of these neurons giving off abnormal "sprouting" processes. Double labeling demonstrated that many of these neurons contained tangle-like or granular material that was immunoreactive for abnormal forms of tau and stained with thioflavine S, indicating that these neurons are in a transitional degenerative stage. An antibody to phosphorylated neurofilament proteins labeled a subset of neurofibrillary tangles in the Alzheimer's disease cases. However, following formic acid pre-treatment, the number of neurofibrillary tangles showing phosphorylated neurofilament protein immunoreactivity increased, with double labeling confirming that all of the tau-immunoreactive neurofibrillary tangles were also immunoreactive for phosphorylated neurofilament proteins. Immunoblotting demonstrated that there was a proportionately greater amount of the neurofilament triplet subunit proteins in hippocampal tissue from Alzheimer's disease cases as compared to controls. These results indicate that there are changes in the cytoskeleton of CA1 neurons associated with age which are likely to involve an increase in the level of neurofilament proteins and may be a predisposing factor contributing towards their high degree of vulnerability in degenerative conditions such as Alzheimer's disease. The cellular factors affecting hippocampal neurons during aging may be potentiated in Alzheimer's disease to result in even higher levels of intracellular neurofilament proteins and the progressive alterations of neurofilaments and other cytoskeletal proteins that finally results in neurofibrillary tangle formation and cellular degeneration.

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Educaworks Oy on toiminut viisi vuotta oppimistehtaana, jonka omistajia ovat olleet yritykset ja oppilaitokset. Yrityksen pääasiallisia työntekijöitä ovat tähän mennessä olleet ammattiopiston työssäoppijat ja parina viimeisenä vuotena on yrityksellä ollut palkkalistoillaan omia työntekijöitä. Tässä työssä luotiin vaihtoehtoja Educaworks Oy:n tulevalle toiminnalle lähtien siitä, että tämä nykyinen toimintamalli on tullut tiensä päähän ja tarvitaan uusi malli toiminnan jatkamiselle.Työssä haettiin hyviä käytäntöjä Suomesta benchmarkingin avulla. Näiden mallienvahvuuksia hyödyntämällä pystyttiin kehittämään vaihtoehto Educaworks Oy:n tulevalle toiminnalle. Tämä malli, oppimistehdas osana osaamiskeskittymää, valittiin toteutettavaksi kolmesta eri vaihtoehdosta, joista kaksi muuta olivat oppimistehdas yrityksenä ja oppimistehdas osana koulutusorganisaatiota. Valitussa vaihtoehdossa hyödynnetään Savonia-ammattikorkeakoulun suunnitteilla olevaa EducaTech Center-hanketta, jossa on tarkoitus luoda Iisalmeen teknologiateollisuuden osaamiskeskittymä seuraavan EU-kauden 2007-2013 aikana. Valitussa mallissa Educaworks Oy hyödyntää tulevassa toiminnassaan tämän osaamiskeskittymän uutta kone- ja laitekantaa sekä tekee yhteistyötä keskittymän tutkimus- ja tuotekehityshenkilökunnan kanssa. Yritykset pääsevät parhaiten osallisiksi Educa Tech Center osaamiskeskittymän tuottamista palveluista hankkimalla Educaworks Oy:n osakkeita ja pääsemällä täten keskittymän ytimeen sen tuotannollisen toimijan, Educaworks Oy:n, avulla. Educaworks Oy toimii tässä keskittymässä komponenttitoimittajan roolissa ollen malli komponenttitoimittajasta muillealueella oleville vastaaville verkostoissa toimiville yrityksille. Educaworks Oy:n toiminnan toisena periaatteena tulee olemaan työssäoppiminen. Työssäoppiminen on tänä päivänä osa ammatillista koulutusta ja sen merkityskorostuu yhä enemmän, koska oppilaat tulevat opiskelemaan tänä päivänä monesti lähtökohdista, joissa heillä ei ole ollut mahdollisuutta harjoittaa käytännön taitojaan ennen ammatillisten opiskelujen aloittamista. Työpaikoilla ei ole vielä kovin hyvää valmiutta toteuttaa sitä opetushallituksen tavoitetta, että oppilaatoppisivat työssäoppimisjaksoilla uusia asioita ohjatusti. Työpaikoilta puuttuu työssäoppimisen ohjaajat ja oppilaiden tekemät harjoitteet ovat liian monta kertaa ammatillisesti kovin vaatimattomia jäysteenpoisto- tai kappaleenvaihtotöitä koneistuksesta puhuttaessa. Tässä työssä luodaan mallia oppilaiden ohjatulle työssäoppimiselle tehtyjen tieteellisten tutkimusten pohjalta. Tavoitteena on, että Educaworks Oy:ssä pystyttäisiin jatkossa kouluttamaan myös muiden alueen teknologiateollisuuden yritysten työntekijöitä toimimaan työssäoppimisen ohjaajina.

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Interconnection of loads and small size generation forms a new type of distribution systems, the Microgrid. The microgrids can be operated together with the utility grid or be operated autonomously in an island. Thesesmall grids present a new paradigm of the construction of the low voltage distribution systems. The microgrids in the distribution systems can become small, controllable units, which immediately react to the system's changes. Along with that the microgrids can realize the special properties, such as increasing the reliability, reducing losses, voltage sag correction, uninterruptible supplying. The goals of the thesis are to explain the principles of the microgrid's functioning, to clarify the main ideas and positive features of the microgrids, to find out and prove their advantages and explain why they are so popular nowadays all over the world. The practical aims of the thesis are to construct and build a test setup of a microgrid based on two inverters from SMA Technologie AG in the laboratory and to test all the main modes and parameters of the microgrid's operating. Also the purpose of the thesis is to test the main component of the microgrid - the battery inverter which controls allthe processes and energy flows inside a microgrid and communicates with the main grid. Based on received data the main contribution of the thesis consists of the estimation of the established microgrid from the reliability, economy and simplicity of operating points of view and evaluation ofthe advisability of its use in different conditions. Moreover, the thesis assumes to give the recommendations and advice for the future investigations of the built system.

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We compared the pupil responses originating from outer versus inner retinal photoreception between patients with isolated hereditary optic neuropathy (HON, n = 8) and healthy controls (n = 8). Three different testing protocols were used. For the first two protocols, a response function of the maximal pupil contraction versus stimulus light intensity was generated and the intensity at which half of the maximal pupil contraction, the half-max intensity, was determined. For the third protocol, the pupil size after light offset, the re-dilation rate and re-dilation amplitude were calculated to assess the post-light stimulus response. Patients with HON had bilateral, symmetric optic atrophy and significant reduction of visual acuity and visual field compared to controls. There were no significant mean differences in the response curve and pupil response parameters that reflect mainly rod, cone or melanopsin activity between patients and controls. In patients, there was a significant correlation between the half-max intensity of the red light sequence and visual field loss. In conclusion, pupil responses derived from outer or inner retinal photoreception in HON patients having mild-to moderate visual dysfunction are not quantitatively different from age-matched controls. However, an association between the degree of visual field loss and the half-max intensity of the cone response suggests that more advanced stages of disease may lead to impaired pupil light reflexes.

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Two doses of synthetic atrial natriuretic peptide (0.5 and 5.0 micrograms/min) and its vehicle were infused intravenously for 4 hours in eight salt-loaded normal volunteers, and the effect on blood pressure, heart rate, renal hemodynamics, solute excretion, and secretion of vasoactive hormones was studied. The 0.5 micrograms/min infusion did not alter blood pressure or heart rate, whereas the 5.0 micrograms/min infusion significantly reduced the mean pressure by 20/9 mm Hg after 2.5 to 3 hours and increased the heart rate slightly. Inulin clearance was not significantly changed, but the mean p-aminohippurate clearance fell by 13 and 32% with the lower and higher doses, respectively. Urinary excretion of sodium and chloride increased slightly with the lower dose. With the higher dose, a marked increase in urinary excretion of sodium, chloride, and calcium was observed, reaching a peak during the second hour of the infusion. Potassium and phosphate excretion did not change significantly. A brisk increase in urine flow rate and fractional water excretion was seen only during the first hour of the high-dose infusion. Signs and symptoms of hypotension were observed in two subjects. No change in plasma renin activity, angiotensin II, or aldosterone was observed during either infusion, but a marked increase occurred after discontinuation of the high-dose infusion. In conclusion, the 5 micrograms/min infusion induced a transient diuretic effect, delayed maximal natriuretic activity, and a late fall in blood pressure, with no change in inulin clearance but a dose-related decrease in p-aminohippurate clearance. Despite large amounts of sodium excreted and blood pressure reduction, no counterregulatory changes were observed in the renin-angiotensin-aldosterone system or plasma vasopressin levels during the infusion.

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Laboratory values of the most commonly assayed clinical chemistry variables were determined in selected elderly and healthy ambulatory populations. The upper and lower limits (2.5 and 97.5 fractiles) were compared with the adult reference values in use in university hospitals of Switzerland. The results suggest that conventional adult reference values can be used for most variables in the elderly and that these values are also useful in an ambulatory population.

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In this study, we evaluated the repeatability of pupil responses to colored light stimuli in healthy subjects using a prototype chromatic pupillometer. One eye of 10 healthy subjects was tested twice in the same day using monochromatic light exposure at two selected wavelengths (660 and 470 nm, intensity 300 cd/m(2)) presented continuously for 20 s. Pupil responses were recorded in real-time before, during, and after light exposure. Maximal contraction amplitude and sustained contraction amplitude were calculated. In addition, we quantified the summed pupil response during continuous light stimulation as the total area between a reference line representing baseline pupil size and the line representing actual pupil size over 20 s (area under the curve). There was no significant difference in the repeated measure compared to the first test for any of the pupil response parameters. In conclusion, we have developed a novel prototype of color pupillometer which demonstrates good repeatability in evoking and recording the pupillary response to a bright blue and red light stimulus.

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VVALOSADE is a research project of professor Anita Lukka's VALORE research team in the Lappeenranta University of Technology. The VALOSADE includes the ELO technology program of Tekes. SMILE is one of four subprojects of the VALOSADE. The SMILE study focuses on the case of the company network that is composed of small and micro-sized mechanical maintenance service providers and forest industry as large-scale customers. The basic principle of the SMILE study is the communication and ebusiness in supply and demand networks. The aim of the study is to develop ebusiness strategy, ebusiness model and e-processes among the SME local service providers, and onthe other hand, between the local service provider network and the forest industry customers in a maintenance and operations service business. A literature review, interviews and benchmarking are used as research methods in this qualitative case study. The first SMILE report, 'Ebusiness between Global Company and Its Local SME Supplier Network', concentrated on creating background for the SMILE study by studying general trends of ebusiness in supply chains and networks of different industries. This second phase of the study concentrates on case network background, such as business relationships, information systems and business objectives; core processes in maintenance and operations service network; development needs in communication among the network participants; and ICT solutions to respond needs in changing environment. In the theory part of the report, different ebusiness models and frameworks are introduced. Those models and frameworks are compared to empirical case data. From that analysis of the empirical data, therecommendations for the development of the network information system are derived. In process industry such as the forest industry, it is crucial to achieve a high level of operational efficiency and reliability, which sets up great requirements for maintenance and operations. Therefore, partnerships or strategic alliances are needed between the network participants. In partnerships and alliances, deep communication is important, and therefore the information systems in the network also are critical. Communication, coordination and collaboration will increase in the case network in the future, because network resources must be optimised to improve competitive capability of the forest industry customers and theefficiency of their service providers. At present, ebusiness systems are not usual in this maintenance network. A network information system among the forest industry customers and their local service providers actually is the only genuinenetwork information system in this total network. However, the utilisation of that system has been quite insignificant. The current system does not add value enough either to the customers or to the local service providers. At present, thenetwork information system is the infomediary that share static information forthe network partners. The network information system should be the transaction intermediary, which integrates internal processes of the network companies; the network information system, which provides common standardised processes for thelocal service providers; and the infomediary, which share static and dynamic information on right time, on right partner, on right costs, on right format and on right quality. This study provides recommendations how to develop this system in the future to add value to the network companies. Ebusiness scenarios, vision, objectives, strategies, application architecture, ebusiness model, core processes and development strategy must be considered when the network information system will be developed in the next development step. The core processes in the case network are demand/capacity management, customer/supplier relationship management, service delivery management, knowledge management and cash flow management. Most benefits from ebusiness solutions come from the electrifying of operational level processes, such as service delivery management and cash flow management.

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The application of forced unsteady-state reactors in case of selective catalytic reduction of nitrogen oxides (NOx) with ammonia (NH3) is sustained by the fact that favorable temperature and composition distributions which cannot be achieved in any steady-state regime can be obtained by means of unsteady-state operations. In a normal way of operation the low exothermicity of the selective catalytic reduction (SCR) reaction (usually carried out in the range of 280-350°C) is not enough to maintain by itself the chemical reaction. A normal mode of operation usually requires supply of supplementary heat increasing in this way the overall process operation cost. Through forced unsteady-state operation, the main advantage that can be obtained when exothermic reactions take place is the possibility of trapping, beside the ammonia, the moving heat wave inside the catalytic bed. The unsteady state-operation enables the exploitation of the thermal storage capacity of the catalyticbed. The catalytic bed acts as a regenerative heat exchanger allowing auto-thermal behaviour when the adiabatic temperature rise is low. Finding the optimum reactor configuration, employing the most suitable operation model and identifying the reactor behavior are highly important steps in order to configure a proper device for industrial applications. The Reverse Flow Reactor (RFR) - a forced unsteady state reactor - corresponds to the above mentioned characteristics and may be employed as an efficient device for the treatment of dilute pollutant mixtures. As a main disadvantage, beside its advantages, the RFR presents the 'wash out' phenomena. This phenomenon represents emissions of unconverted reactants at every switch of the flow direction. As a consequence our attention was focused on finding an alternative reactor configuration for RFR which is not affected by the incontrollable emissions of unconverted reactants. In this respect the Reactor Network (RN) was investigated. Its configuration consists of several reactors connected in a closed sequence, simulating a moving bed by changing the reactants feeding position. In the RN the flow direction is maintained in the same way ensuring uniformcatalyst exploitation and in the same time the 'wash out' phenomena is annulated. The simulated moving bed (SMB) can operate in transient mode giving practically constant exit concentration and high conversion levels. The main advantage of the reactor network operation is emphasizedby the possibility to obtain auto-thermal behavior with nearly uniformcatalyst utilization. However, the reactor network presents only a small range of switching times which allow to reach and to maintain an ignited state. Even so a proper study of the complex behavior of the RN may give the necessary information to overcome all the difficulties that can appear in the RN operation. The unsteady-state reactors complexity arises from the fact that these reactor types are characterized by short contact times and complex interaction between heat and mass transportphenomena. Such complex interactions can give rise to a remarkable complex dynamic behavior characterized by a set of spatial-temporal patterns, chaotic changes in concentration and traveling waves of heat or chemical reactivity. The main efforts of the current research studies concern the improvement of contact modalities between reactants, the possibility of thermal wave storage inside the reactor and the improvement of the kinetic activity of the catalyst used. Paying attention to the above mentioned aspects is important when higher activity even at low feeding temperatures and low emissions of unconverted reactants are the main operation concerns. Also, the prediction of the reactor pseudo or steady-state performance (regarding the conversion, selectivity and thermal behavior) and the dynamicreactor response during exploitation are important aspects in finding the optimal control strategy for the forced unsteady state catalytic tubular reactors. The design of an adapted reactor requires knowledge about the influence of its operating conditions on the overall process performance and a precise evaluation of the operating parameters rage for which a sustained dynamic behavior is obtained. An apriori estimation of the system parameters result in diminution of the computational efforts. Usually the convergence of unsteady state reactor systems requires integration over hundreds of cycles depending on the initial guess of the parameter values. The investigation of various operation models and thermal transfer strategies give reliable means to obtain recuperative and regenerative devices which are capable to maintain an auto-thermal behavior in case of low exothermic reactions. In the present research work a gradual analysis of the SCR of NOx with ammonia process in forced unsteady-state reactors was realized. The investigation covers the presentationof the general problematic related to the effect of noxious emissions in the environment, the analysis of the suitable catalysts types for the process, the mathematical analysis approach for modeling and finding the system solutions and the experimental investigation of the device found to be more suitable for the present process. In order to gain information about the forced unsteady state reactor design, operation, important system parameters and their values, mathematical description, mathematicalmethod for solving systems of partial differential equations and other specific aspects, in a fast and easy way, and a case based reasoning (CBR) approach has been used. This approach, using the experience of past similarproblems and their adapted solutions, may provide a method for gaining informations and solutions for new problems related to the forced unsteady state reactors technology. As a consequence a CBR system was implemented and a corresponding tool was developed. Further on, grooving up the hypothesis of isothermal operation, the investigation by means of numerical simulation of the feasibility of the SCR of NOx with ammonia in the RFRand in the RN with variable feeding position was realized. The hypothesis of non-isothermal operation was taken into account because in our opinion ifa commercial catalyst is considered, is not possible to modify the chemical activity and its adsorptive capacity to improve the operation butis possible to change the operation regime. In order to identify the most suitable device for the unsteady state reduction of NOx with ammonia, considering the perspective of recuperative and regenerative devices, a comparative analysis of the above mentioned two devices performance was realized. The assumption of isothermal conditions in the beginningof the forced unsteadystate investigation allowed the simplification of the analysis enabling to focus on the impact of the conditions and mode of operation on the dynamic features caused by the trapping of one reactant in the reactor, without considering the impact of thermal effect on overall reactor performance. The non-isothermal system approach has been investigated in order to point out the important influence of the thermal effect on overall reactor performance, studying the possibility of RFR and RN utilization as recuperative and regenerative devices and the possibility of achieving a sustained auto-thermal behavior in case of lowexothermic reaction of SCR of NOx with ammonia and low temperature gasfeeding. Beside the influence of the thermal effect, the influence of the principal operating parameters, as switching time, inlet flow rate and initial catalyst temperature have been stressed. This analysis is important not only because it allows a comparison between the two devices and optimisation of the operation, but also the switching time is the main operating parameter. An appropriate choice of this parameter enables the fulfilment of the process constraints. The level of the conversions achieved, the more uniform temperature profiles, the uniformity ofcatalyst exploitation and the much simpler mode of operation imposed the RN as a much more suitable device for SCR of NOx with ammonia, in usual operation and also in the perspective of control strategy implementation. Theoretical simplified models have also been proposed in order to describe the forced unsteady state reactors performance and to estimate their internal temperature and concentration profiles. The general idea was to extend the study of catalytic reactor dynamics taking into account the perspectives that haven't been analyzed yet. The experimental investigation ofRN revealed a good agreement between the data obtained by model simulation and the ones obtained experimentally.

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O objetivo do trabalho foi avaliar os efeitos de GA3, nas concentrações de 100; 200 e 300mg L-1 e do bioestimulante Stimulate®, em doses de 2,08; 4,17 e 6,25mL L-1, em duas aplicações via foliar, acrescidas de espalhante adesivo Silwett® a 0,05% e a exposição dos ramos à luminosidade, na indução floral e produtividade do maracujazeiro-amarelo, em condições de safra normal, em Araguari-MG. Aos 30 dias após a primeira aplicação dos tratamentos, iniciaram-se as avaliações do número de flores, com contagens diárias, nos dois lados da espaldeira, nos meses de setembro de 2002 a março de 2003. As colheitas dos frutos foram realizadas semanalmente, no período de novembro de 2002 a abril de 2003, observando-se a produção. O GA3 e o Stimulate não proporcionaram efeito significativo no número de flores, nas sete épocas, assim como no número total de flores. Não houve efeito dos tratamentos para a produtividade e produção total de frutos. Os ramos sob luminosidade pela tarde apresentaram maior número de flores, nos meses de setembro, dezembro, fevereiro e março. A interação entre os tratamentos e a exposição dos ramos à luminosidade não foi significativa para o número de flores, nas épocas avaliadas.

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PURPOSE: To compare qualitative and quantitative magnetic resonance (MR) imaging characteristics of hepatic hemangiomas in patients with normal, fibrotic and cirrhotic livers. MATERIALS AND METHODS: Retrospective, institutional review board approved study (waiver of informed consent). Eighty-nine consecutive patients with 231 hepatic hemangiomas who underwent liver MR imaging for lesion characterization were included. Lesions were classified into three groups according to the patients' liver condition: no underlying liver disease (group 1), fibrosis (group 2) and cirrhosis (group 3). Qualitative and quantitative characteristics (number, size, signal intensities on T1-, T2-, and DW MR images, T2 shine-through effect, enhancement patterns (classical, rapidly filling, delayed filling), and ADC values) were compared. RESULTS: There were 160 (69%), 45 (20%), and 26 (11%) hemangiomas in groups 1, 2 and 3, respectively. Lesions were larger in patients with normal liver (group 1 vs. groups 2 and 3; P=.009). No difference was found between the groups on T2-weighted images (fat-suppressed fast spin-echo (P=.82) and single-shot (P=.25)) and in enhancement patterns (P=.56). Mean ADC values of hemangiomas were similar between groups 1, 2 and 3 (2.11±.52×10(-3)mm(2)/s, 2.1±.53×10(-3)mm(2)/s and 2.14±.44×10(-3)mm(2)/s, P=87, respectively). T2 shine-through effect was less frequently observed in cirrhosis (P=.02). CONCLUSION: MR imaging characteristics of hepatic hemangioma were similar in patients with normal compared to fibrotic and cirrhotic livers. Smaller lesion size was observed with liver disease and less T2 shine-through effect was seen in hemangiomas developed on cirrhosis, the latter being an important finding to highlight in these patients at risk of developing hepatocellular carcinoma.