928 resultados para essence of operation


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The primary objective of this research was to demonstrate the benefits of NDT technologies for effectively detecting and characterizing deterioration in bridge decks. In particular, the objectives were to demonstrate the capabilities of ground-penetrating radar (GPR) and impact echo (IE), and to evaluate and describe the condition of nine bridge decks proposed by Iowa DOT. The first part of the report provides a detailed review of the most important deterioration processes in concrete decks, followed by a discussion of the five NDT technologies utilized in this project. In addition to GPR and IE methods, three other technologies were utilized, namely: half-cell (HC) potential, electrical resistivity (ER), and ultrasonic surface waves (USW) method. The review includes a description of the principles of operation, field implementation, data analysis, and interpretation; information regarding their advantages and limitations in bridge deck evaluations and condition monitoring are also implicitly provided.. The second part of the report provides descriptions and bridge deck evaluation results from the nine bridges. The results of the NDT surveys are described in terms of condition assessment maps and are compared with the observations obtained from the recovered cores or conducted bridge deck rehabilitation. Results from this study confirm that the used technologies can provide detailed and accurate information about a certain type of deterioration, electrochemical environment, or defect. However, they also show that a comprehensive condition assessment of bridge decks can be achieved only through a complementary use of multiple technologies at this stage,. Recommendations are provided for the optimum implementation of NDT technologies for the condition assessment and monitoring of bridge decks.

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Underbody plows can be very useful tools in winter maintenance, especially when compacted snow or hard ice must be removed from the roadway. By the application of significant down-force, and the use of an appropriate cutting edge angle, compacted snow and ice can be removed very effectively by such plows, with much greater efficiency than any other tool under those circumstances. However, the successful operation of an underbody plow requires considerable skill. If too little down pressure is applied to the plow, then it will not cut the ice or compacted snow. However, if too much force is applied, then either the cutting edge may gouge the road surface, causing significant damage often to both the road surface and the plow, or the plow may ride up on the cutting edge so that it is no longer controllable by the operator. Spinning of the truck in such situations is easily accomplished. Further, excessive down force will result in rapid wear of the cutting edge. Given this need for a high level of operator skill, the operation of an underbody plow is a candidate for automation. In order to successfully automate the operation of an underbody plow, a control system must be developed that follows a set of rules that represent appropriate operation of such a plow. These rules have been developed, based upon earlier work in which operational underbody plows were instrumented to determine the loading upon them (both vertical and horizontal) and the angle at which the blade was operating.These rules have been successfully coded into two different computer programs, both using the MatLab® software. In the first program, various load and angle inputs are analyzed to determine when, whether, and how they violate the rules of operation. This program is essentially deterministic in nature. In the second program, the Simulink® package in the MatLab® software system was used to implement these rules using fuzzy logic. Fuzzy logic essentially replaces a fixed and constant rule with one that varies in such a way as to improve operational control. The development of the fuzzy logic in this simulation was achieved simply by using appropriate routines in the computer software, rather than being developed directly. The results of the computer testing and simulation indicate that a fully automated, computer controlled underbody plow is indeed possible. The issue of whether the next steps toward full automation should be taken (and by whom) has also been considered, and the possibility of some sort of joint venture between a Department of Transportation and a vendor has been suggested.

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Many researchers have concluded that secondary or delayed ettringite is responsible for serious premature deterioration of concrete highways. In some poorly performing Iowa concretes, ettringite is the most common secondary mineral but its role in premature deterioration is uncertain since some researchers still maintain that secondary ettringite does not itself cause deterioration. The current research project was designed to determine experimentally if it is possible to reduce secondary ettringite formation in concrete by treating the concrete with commercial crystallization inhibitor chemicals. The hypothesis is such that if the amount of ettringite is reduced, there will also be a concomitant reduction of concrete expansion and cracking. If both ettringite formation and deterioration are simultaneously reduced, then the case for ettringite induced expansion/cracking is strengthened. The experiment used four commercial inhibitors - two phosphonates, a polyacrylic acid, and a phosphate ester. Concrete blocks were subjected to continuous immersion, wet/dry and freeze/thaw cycling in sodium sulfate solutions and in sulfate solutions containing an inhibitor. The two phosphonate inhibitors, Dequest 2060 and Dequest 2010, manufactured by Monsanto Co., were effective in reducing ettringite nucleation and growth in concrete. Two other inhibitors, Good-rite K752 and Wayhib S were somewhat effective, but less so than the two phosphonates. Rapid experiments with solution growth inhibition of ettringite without the presence of concrete phases were used to explore the mechanisms of inhibition of this mineral. Reduction of new ettringite formation in concrete blocks also reduced expansion and cracking of the blocks. This relationship clearly links concrete expansion with this mineral - a conclusion that some research workers have disputed despite theoretical arguments for such a relationship and despite numerous observations of ettringite mineralization in prematurely deteriorated concrete highways. Secondary ettringite nucleation and growth must cause concrete expansion because the only known effect of the inhibitor chemicals is to reduce crystal nucleation and growth, and the inhibitors cannot in any other way be responsible for the reduction in expansion. The mechanism of operation of the inhibitors on ettringite reduction is not entirely clear but the solution growth experiments show that they prevent crystallization of a soluble ettringite precursor gel. The present study shows that ettringite growth alone is not responsible for expansion cracking because the experiments showed that most expansion occurs under wet/dry cycling, less under freeze/thaw cycling, and least under continuous soaking conditions. It was concluded from the different amounts of damage that water absorption by newly-formed, minute ettringite crystals is responsible for part of the observed expansion under wet/dry conditions, and that reduction of freeze resistance by ettringite filling of air-entrainment voids is also important in freeze/thaw environments.

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OBJECTIVES: Studies of small area variations of health care utilization are more and more frequent. Such variations are often considered to be an indication of variations in the quality of medical care. The variations in the rate of operations for hip fractures are among the lowest studied to date, due to the fact that a consensus exists concerning this surgery. Our objective is to examine these variations within the context of relatively small and heterogeneous districts. METHOD: Based on anonymous computerized data on public hospital stays, this study describes the variations in population rates (crude and standardized) of operations for hip fracture among the health districts of the Canton of Vaud for the period from 1986 to 1991. District populations vary from 22,000 to 164,000. Using the extremal quotient (EQ), the importance of these variations was determined. RESULTS: The study population consists of 2363 cases, of which 78% are women. Mean age is 80.4 for women and 70.6 for men. Standardized rates of operation for hip fracture per 100,000 in the Canton Vaud for the years 1986 to 1991 are, respectively: 56; 67; 86; 91; 89 and 94. The EQ for the years 1986 to 1991 are respectively: 8.2; 4.0; 3.5; 2.7; 1.9 and 1.9. The high EQ, especially for the earlier years, are contrary to the initial premise of absence of variation. The progressive implementation in the Canton Vaud of VESKA medical statistics could play a role, as could the small size of many of the districts, with resultant instability of rates. CONCLUSIONS: Considering the wide variations shown here for an operation hardly regarded as subject to variations, it is important to exercise caution in interpreting published data of small area variations.

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Portland cement concrete (PCC) pavement undergoes repeated environmental load-related deflection resulting from temperature and moisture variations across pavement depth. This has been recognized as resulting in PCC pavement curling and warping since the mid-1920s. Slab curvature can be further magnified under repeated traffic loads and may ultimately lead to fatigue failures, including top-down and bottom-up transverse, longitudinal, and corner cracking. It is therefore significant to measure the “true” degree of curling and warping in PCC pavements, not only for quality control (QC) and quality assurance (QA) purposes, but also for better understanding of its relationship to long-term pavement performance. Although several approaches and devices—including linear variable differential transducers (LVDTs), digital indicators, and some profilers—have been proposed for measuring curling and warping, their application in the field is subject to cost, inconvenience, and complexity of operation. This research therefore explores developing an economical and simple device for measuring curling and warping in concrete pavements with accuracy comparable to or better than existing methodologies. Technical requirements were identified to establish assessment criteria for development, and field tests were conducted to modify the device to further enhancement. The finalized device is about 12 inches in height and 18 pounds in weight, and its manufacturing cost is just $320. Detailed development procedures and evaluation results for the new curling and warping measuring device are presented and discussed, with a focus on achieving reliable curling and warping measurements in a cost effective manner.

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Diplomityön tavoitteena oli selvittää, kuinka kohdeyrityksessä nykyhetkellä pitkältiräätälöitynä tuotetut putkilämmönvaihtimet voitaisiin standardisoida, jotta pystyttäisiin kohdistamaan resursseja oikein ja parantamaan siten yrityksen taloudellista suorituskykyä. Tutkimuksen edetessä määräävimmäksi tekijäksi työn tuloksia ajatellen nousi taloudellinen standardisointiaste, jonka perusteeksi kohdeyrityksen putkilämmönvaihtimissa valittiin standardisoitu suunnitteluohjeisto. Suunnitteluohjeiston lisäksi tuotestandardiin liitettiin ehdotus toimintapojen automatisoimisesta parametrisen valintataulukon sekä sähköisen manuaalin avulla. Työssä tuotestandardisointia tarkastellaan rationalisointi-investointina ja sen kannattavuutta on tarkasteltu investointilaskelmien sekä herkkyys analyysin avulla. Alkuarvot investointilaskelmissa perustuvat työssä yhdelle putkilämmönvaihtimelletoteutettuun tuotestandardisointitapaan, jos tätä tapaa käytettäisiin jatkossa kaikkiin kyseisen yksikön putkilämmönvaihtimiin.

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Tässä työssä on esitetty väsyttävän kuormituksen mittaamiseen ja mittausdatan jälkikäsittelyyn sekä väsymismitoitukseen liittyviä menetelmiä. Menetelmien sovelluskohteena oli metsäkoneen kuormain, joka on väsyttävästi kuormitettu hitsattu rakenne. Teoriaosassa on kuvattu väsymisilmiötä ja väsymismitoitusmenetelmiä sekä kuormitusten tunnistamiseen ja mittausten jälkikäsittelyyn liittyviä menetelmiä. Yleisimmin käytettyjen väsymismitoitusmenetelmien rinnalle on esitetty luotettavuuteen perustuvaa väsymismitoitusmenetelmää. Kuormainten suunnittelussa on keveys- j a kestoikävaatimusten takia erityisen suuri merkitys väsymisen huomioimisella. Rakenteille on ominaista tietyt toiminnan kannalta välttämättömät hitsatut yksityiskohdat, jotka usein määräävät koko rakenteen kestoiän. Koska nämä ongelmakohdat pystytään useimmiten tunnistamaan jo suunnitteluvaiheessa, voidaan yksityiskohtien muotoilulla usein parantaa huomattavasti koko rakenteen kestoikää. Näiden yksityiskohtien optimointi on osittain mahdollista toteuttaa ilman kuormituskertymätietoa, mutta useimmiten kuormitusten tunnistaminen on edellytys parhaan ratkaisun löytymiselle. Tällöin toistaiseksi paras keino todellisen väsyttävän kuormituksen tunnistamiseksi on pitkäaikaiset kenttämittaukset. Kenttämittauksilla selvitetään rakenteeseen kohdistuvat kuormitukset venymäliuskojen avulla. Kuormitusten tunnistamisella on erityisen suuri merkitys kun halutaan määrittää rakenteen kestoikä. Väsyminen ja väsyttävä kuormitus ovat kuitenkin tilastollisia muuttujia j a yksittäiselle rakenteelle ei ole mahdollista määrittää tarkkaa k estoikää. Tilastollisia menetelmiä käyttäen on kuitenkin mahdollista määrittää rakenteen vaurioitumisriski. Laskettaessa vaurioitumisriskiä suurelle määrälle yksittäisiä rakenteita voidaan muodostaa tarkkojakin ennusteita mahdollisten vaurioiden lukumäärästä. Tällöin kuormituskertymätiedosta voi olla tavanomaisen suunnittelun lisäksi laajempaa hyötyä esimerkiksi takuukäsittelyssä. Tässä työssä on sovellettu esitettyjä teorioita käytännössä metsäkoneen harvesterin puomiston väsymistarkasteluun. Kyseisen rakenteen kuormituksia mitattiin kahden viikon aikana yhteensä 35 tuntia, jonka perusteella laskettiin väsyttävän kuormituksen tilastollinen jakauma esimerkkitapaukselle. Mittauksen perusteella ei voitu tehdä kuitenkaan johtopäätöksiä tuotteen koko elinkaaren kuormituksista eikä muiden samanlaisten tuotteiden kuormituksista, koska mitattu otos oli suhteellisen lyhyt ja rajoittui vain yhteen käyttäjään ja muutamaan käyttökohteeseen. Menetelmien testaamiseksi kyseinen otos oli kuitenkin riittävä. Kuormituskertymätietoa käytettiin hyväksi myös laatumääritysten muodostamisessaesimerkkitapaukselle. Murtumismekaniikkaan perustuvalla menetelmällä arvioitiinharvesteripilarin valun mahdollisten valuvirheiden suurin sallittu koko. Luotettavuuteen pohjautuvan mitoitusmenettelyn tarve näyttää olevanlisääntymässä, joten pitkäaikaisten kenttämittausten tehokas hyödyntäminen tulee olemaan keskeinen osa väsymismitoitusta lähitulevaisuudessa. Menetelmiä olisi mahdollista tehostaa yhdistämällä kuormituskertymään erilaisia kuormitusten suhteen riippuvia tunnettuja suureita kuten käsiteltävän puun halkaisija. Todellisettuotekohtaiset tilastolliset jakaumat kuormituksista voitaisiin muodostaa mahdollisesti tehokkaammin, jos esimerkiksi kuormitusten riippuvuus metsätyypistä pystyttäisiin ensin määrittämään.

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INTRODUCTION: Preoperative scores are widely used predictors of complications after major surgery. These scores, however, are not widely used in transurethral procedures. The aim of this study was to assess the value of the Charlson Comorbidity Index (CCI), the age-adjusted CCI, the American Society of Anesthesiologist score (ASA) and the Nutritional Risk Score (NRS) in predicting early morbidity after transurethral urological procedures. METHODS: Consecutive patients undergoing transurethral resection of the bladder or the prostate were prospectively enrolled. The scores were calculated preoperatively; 30-day complications were prospectively recorded according to the Dindo-Clavien classification. Univariate logistic regression was performed to investigate the value of each score and of other factors (i.e., age, sex, body mass index, anemia, smoking habit, type of operation and anaesthesia) as predictors of complications. A multivariate model was then calculated using these predictors. RESULTS: Overall, 197 patients were included. The mean age was 72 (standard deviation ± 10). In total, 26.9% patients had at least 1 complication. Using univariate analysis, we found that each score significantly predicted complications. In multivariate analysis, only the ASA (odds ration [OR] 2.11; 95% confidence interval [CI] 1.01-4.43) and the NRS (OR 2.42; 95% CI 1.56-3.74) remained independent predictors. The best model incorporated ASA, NRS and gender, and predicted morbidity with an area under the curve of 76%. Our study's main limitations are population heterogeneity and limited sample size. CONCLUSION: The ASA and the NRS are important and independent determinants of early morbidity after transurethral procedures. The use of these indices may assist clinicians in the decision-making process to balance the possible benefits of transurethral procedures with the potential risks.

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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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In this thesis the membrane filtration equipment for plate type ceramic membranes was developed based on filtration results achieved with different kinds of wastewaters. The experiments were mainly made with pulp and board mill wastewaters, but some experiments were also made with a bore well water and a stone cutting mine wastewater. The ceramicmembranes used were alpha-alumina membranes with a pore size of 100 nm. Some ofthe membranes were coated with a gamma-alumina layer to reduce the membrane pore size to 10 nm, and some of them were modified with different metal oxides in order to change the surface properties of the membranes. The effects of operationparameters, such as cross-flow velocity, filtration pressure and backflushing on filtration performance were studied. The measured parameters were the permeateflux, the quality of the permeate, as well as the fouling tendency of the membrane. A dynamic membrane or a cake layer forming on top of the membrane was observed to decrease the flux and increase separa-tion of certain substances, especially at low cross-flow velocities. When the cross-flow velocities were increased the membrane properties became more important. Backflushing could also be used to decrease the thickness of the cake layer and thus it improved the permeate flux. However, backflushing can lead to a reduction of retentions in cases where the cake layer is improving them. The wastewater quality was important for the thickness of the dynamic membrane and the membrane pore size influenced the permeate flux. In general, the optimization of operation conditions is very important for the successful operation of a membrane filtration system. The filtration equipment with a reasonable range of operational conditions is necessary, especiallywhen different kinds of wastewaters are treated. This should be taken into account already in the development stage of a filtration equipment.

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The objective of industrial crystallization is to obtain a crystalline product which has the desired crystal size distribution, mean crystal size, crystal shape, purity, polymorphic and pseudopolymorphic form. Effective control of the product quality requires an understanding of the thermodynamics of the crystallizing system and the effects of operation parameters on the crystalline product properties. Therefore, obtaining reliable in-line information about crystal properties and supersaturation, which is the driving force of crystallization, would be very advantageous. Advanced techniques, such asRaman spectroscopy, attenuated total reflection Fourier transform infrared (ATR FTIR) spectroscopy, and in-line imaging techniques, offer great potential for obtaining reliable information during crystallization, and thus giving a better understanding of the fundamental mechanisms (nucleation and crystal growth) involved. In the present work, the relative stability of anhydrate and dihydrate carbamazepine in mixed solvents containing water and ethanol were investigated. The kinetics of the solvent mediated phase transformation of the anhydrate to hydrate in the mixed solvents was studied using an in-line Raman immersion probe. The effects of the operation parameters in terms of solvent composition, temperature and the use of certain additives on the phase transformation kineticswere explored. Comparison of the off-line measured solute concentration and the solid-phase composition measured by in-line Raman spectroscopy allowedthe identification of the fundamental processes during the phase transformation. The effects of thermodynamic and kinetic factors on the anhydrate/hydrate phase of carbamazepine crystals during cooling crystallization were also investigated. The effect of certain additives on the batch cooling crystallization of potassium dihydrogen phosphate (KDP) wasinvestigated. The crystal growth rate of a certain crystal face was determined from images taken with an in-line video microscope. An in-line image processing method was developed to characterize the size and shape of thecrystals. An ATR FTIR and a laser reflection particle size analyzer were used to study the effects of cooling modes and seeding parameters onthe final crystal size distribution of an organic compound C15. Based on the obtained results, an operation condition was proposed which gives improved product property in terms of increased mean crystal size and narrowersize distribution.

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PURPOSE: (1) To assess the outcomes of minimally invasive simple prostatectomy (MISP) for the treatment of symptomatic benign prostatic hyperplasia in men with large prostates and (2) to compare them with open simple prostatectomy (OSP). METHODS: A systematic review of outcomes of MISP for benign prostatic hyperplasia with meta-analysis was conducted. The article selection process was conducted according to the PRISMA guidelines. RESULTS: Twenty-seven observational studies with 764 patients were analyzed. The mean prostate volume was 113.5 ml (95 % CI 106-121). The mean increase in Qmax was 14.3 ml/s (95 % CI 13.1-15.6), and the mean improvement in IPSS was 17.2 (95 % CI 15.2-19.2). Mean duration of operation was 141 min (95 % CI 124-159), and the mean intraoperative blood loss was 284 ml (95 % CI 243-325). One hundred and four patients (13.6 %) developed a surgical complication. In comparative studies, length of hospital stay (WMD -1.6 days, p = 0.02), length of catheter use (WMD -1.3 days, p = 0.04) and estimated blood loss (WMD -187 ml, p = 0.015) were significantly lower in the MISP group, while the duration of operation was longer than in OSP (WMD 37.8 min, p < 0.0001). There were no differences in improvements in Qmax, IPSS and perioperative complications between both procedures. The small study sizes, publication bias, lack of systematic complication reporting and short follow-up are limitations. CONCLUSIONS: MISP seems an effective and safe treatment option. It provides similar improvements in Qmax and IPSS as OSP. Despite taking longer, it results in less blood loss and shorter hospital stay. Prospective randomized studies comparing OSP, MISP and laser enucleation are needed to define the standard surgical treatment for large prostates.

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Valtion rajat ylittävät terveyspalvelut Euroopan unionissa sekä Euroopan unionin säädösten merkitys ja vaikutus erityisesti lääkejakeluun ja verenluovuttajille jaettavaan tiedotusaineistoon Valtion rajat ylittävä terveydenhuolto on suuren kiinnostuksen kohteena Euroopan unionissa. Resurssien hyödyntäminen parhaalla mahdollisella tavalla ja tiedon keskittäminen ovat tarpeen terveydenhuollon kustannusten alati noustessa. Terveydenhuoltopalvelut kuuluvat Euroopan sisämarkkinoiden vapaan liikkuvuuden piiriin. Euroopan unionilla ei ole kuitenkaan toimivaltaa säädellä terveydenhuoltojärjestelmiä, vaan sen mahdollisuudet ovat enimmäkseen kansanterveyden edistämisessä ja suojelussa, myös muilla toimialueilla kuin terveydenhuollossa. Tutkimuksen tavoitteena oli tutkia Euroopan unionin säädösten vaikutusta terveydenhuoltosektoriin, erityisesti valtion rajat ylittäviin terveydenhuoltopalveluihin. Erityiskohteena olivat lääkemääräyksen toimittaminen toisen Euroopan unionin jäsenmaan apteekista, resepti-lääkkeiden maahantuonti omaan henkilökohtaiseen käyttöön, sähköisen lääkemääräyksen käyttö kansallisesti ja mahdollisuudet sen käyttöön eri jäsenmaiden välillä, online-apteekkien soveltuvuus Euroopan unionin sisämarkkinoille sekä verenluovuttajille jaettavan tiedotusaineiston yhtenäistämistarve Euroopan unionin alueella. Tutkimuksen osa-alueiden aineisto koottiin vuosina 1999–2003, jolloin Euroopan unioniin kuului 15 jäsenmaata. Apteekit toimittivat useimmiten myös ei-kansalliset, toisessa Euroopan unionin jäsenmaassa annetut lääkemääräykset. Kaikki jäsenmaat rajoittivat lääkemääräyksen vaativien lääkkeiden maahantuontia. Rajoituksia oli maahantuontimäärissä ja -tavoissa. Lisäksi sairasvakuutuskorvausten saaminen ulkomailla lunastetuista reseptilääkkeistä oli hankalaa. Sähköiset lääkemääräykset olivat käytössä vain kahdessa maassa, mutta useissa maissa suunniteltiin niiden kokeilua. Standardit ja käyttöjärjestelmät olivat erilaisia eri maissa. Euroopan unionin alueelle on perustettu online-apteekkeja, joiden toiminta on kuitenkin vaatimatonta. Verenluovuttajille annettava tiedotusaineisto ei missään maassa täyttänyt veridirektiivin vaatimuksia. Tutkimuksen tulokset osoittivat kansallisten käytäntöjen eroavaisuuksien rajoittavan valtion rajat ylittäviä terveydenhuoltopalveluita. Vaikka Euroopan unionin tavoitteena ei ole yhtenäistää terveydenhuoltojärjestelmiä, on tarpeen arvioida uudelleen unionin ja jäsenmaiden välistä työnjakoa. Kansalliset terveydenhuoltojärjestelmät eivät ole erillään Euroopan sisämarkkinoista, jotka merkittävästi vaikuttavat terveydenhuoltoon.

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OBJECTIVE: This study aimed to analyze complaints of patients, their relatives, and friends who consulted a complaints center based (Espace Patients & Proches (EPP)) in a hospital so as to better understand the reasons that motivated them and their underlying expectations. METHODS: This study was based on the analysis of written accounts of the 253 situations that occurred during the first year of operation of the EPP. The accounts were analyzed qualitatively using an inductive, thematic analytic approach. RESULTS: We identified 372 different types of complaints and 28 main analytic themes. Five clustered themes emerged from the analysis of the interconnections among the core themes: (1) interpersonal relationship (N=160-the number of accounts including a complaint related to this general theme); (2) technical aspects of care (N=106); (3) health-care institution (N=69); (4) billing and insurance; (5) access to information (N=13). CONCLUSION: The main reason for patients, their relatives, and friends going to EPP was related to the quality of the interpersonal relationship with health-care professionals. Such complaints were markedly more frequent than those concerning technical aspects of care. PRACTICE IMPLICATIONS: These results raise important questions concerning changing patient expectations as well as how hospitals integrate complaints into the process of quality health care.

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Työn päätavoitteena oli tutkia mobiilipalveluita ja langattomia sovelluksia Suomen terveydenhuollon sektorilla. Tutkimus havainnollistaa avain-alueita, missä mobiilipalvelut ja langattomat sovellukset voivat antaa lisäarvoa perinteiseen lääketieteen harjoittamiseen, ja selvittää, mitkä ovat tähän kehitykseen liittyvät suurimmat ongelmat ja uhkat sekä tutkimustuloksiin pohjautuvat mahdolliset palvelut ja sovellukset 5-10 vuoden kuluttua. Tutkimus oli luonteeltaan kvalitatiivinen ja tutkimuksen toteuttamiseen valittiin tulevaisuudentutkimus ja erityisesti yksi sen menetelmistä, delfoi-menetelmä. Tutkimuksen aineisto kerättiin kahdelta puolistrukturoidulta haastattelukierrokselta. Työn empiirinen osuus keskittyi kuvailemaan Suomen terveydenhuollon sektoria, siinä meneillään olevia projekteja sekä teknisiä esteitä. Lisäksi pyrittiin vastaamaan tutkimuksen pääkysymykseen. Tutkimustulokset osoittivat, että tärkeät alueet, joihin langaton kommunikaatio tulisi vaikuttamaan merkittävästi, ovat ensiaputoiminta, kroonisten potilaiden etämonitorointi, välineiden kehittäminen langattomaan kommunikaatioon kotihoidon parantamiseksi ja uusien toimintamallien luomiseksi sekä lääketieteellinen yhteistyö jakamalla terveydenhuoltoon liittyvät informaation lähteet. Työn tulosten perusteellavoitiin antaa myös muutamia toimenpide-ehdotuksia jatkotutkimuksia varten.