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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Imigrace z Kuby, Venezuely a Brazílie do České republiky od roku 1993 po současnost / Immigration from Cuba, Venezuela, and Brazil to the Czech Republic from the year 1993 to the present

Nováková, Zuzana January 2020 (has links)
The topic of this diploma thesis is immigration from Venezuela, Brazil and Cuba to the Czech Republic from the year 1993 to the present. Political events in Venezula in recent years have increased migration to the neighboring states in region. Therefore, we could expect also increase in immigration from Venezuela to the Czech Republic. Even though the increase did really occur, the population of Venezuelans in the Czech Republic is not so large (mainly due to geographical distance and language barrier) in this diploma thesis will also appear immigration from Brazil and Cuba. Brazil was chosen mainly because the population of Brazilians living in the Czech Republic is the largest of all Latin American countries. Another difference between Venezuela and Brazil is the different mother tongue of immigrants. The last nationality represented are Cubans, whose immigration history to the Czech Republic or originally to the Czechoslovakia differs. During the socialist era, many Cubans lived here due to intergovernmental agreements of Czechoslovak Socialist Republic. Which cannot be said about Venezuelans and Brazilians at that time. According to statistics, even in the mid 1990's, only dozens of Venezuelans and Brazilians lived in the Czech Republic. While at this time lived hundreds of Cubans in the Czech...
62

Leading Change Together: Reducing Organizational Structural Conflict through a Dialogic OD Approach using Liberating Structures

Allen, Barbara 01 January 2018 (has links)
As leaders must increasingly find ways to include and engage others in a power-with approach to competently meet today’s complex challenges, the problem occurs when they find themselves stuck within pre-existing systems structured for exclusion and power-over others. These conventional structures are a source of systemic conflict. This participatory action research/cooperative inquiry case study focuses on the topic of leading organizational change collaboratively in the space between formal hierarchical structures and informal human dynamics using a qualitative methodology. The purpose of this study is to understand how a newly developed Liberating Structures Problem Solving (LSPS) model of facilitation helps participants of a contract manufacturing firm navigate this space through a collaborative dialogic organization development (OD) approach to change within a hierarchical organization structure. The theoretical underpinning of this research is a dialogic OD approach to change using Lipmanowicz and McCandless’s liberating structures group processes grounded in complexity science and social constructionism. The methodological approach is cooperative inquiry, a form of radically participative action research. Triangulation of data was employed using video-recordings, observations, reflections and interviews. The study involved 21 participants from different functions and levels within the organization. Findings demonstrate the importance of including diverse participants in dialogic events; improved communication and relationships; reduced tooling costs; and a modified organizational macrostructure to be more inclusive. Implications of this study suggest the LSPS model was instrumental in helping this organization shift from conventional leadership structures towards a shared leadership approach that helped ignite transformational change.
63

Sample Size Calculations in Simple Linear Regression: A New Approach

Guan, Tianyuan 04 October 2021 (has links)
No description available.
64

A Linear Programming Method for Synthesizing Origin-Destination (O-D) Trip Tables from Traffic Counts for Inconsistent Systems

Lei, Peng 10 August 1998 (has links)
Origin-Destination (O-D) trip tables represent the demand-supply information of each directed zonal-pair in a given region during a given period of time. The effort of this research is to develop a linear programming methodology for estimating O-D trip tables based on observed link volumes. In order to emphasize the nature of uncertainty in the data and in the problem, the developed model permits the user's knowledge of path travel time to vary within a band-width of values, and accordingly modifies the user-optimality principle. The data on the observed flows might also not be complete and need not be perfectly matched. In addition, a prior trip table could also be specified in order to guide the updating process via the model solution. To avoid excessive computational demands required by a total numeration of all possible paths between each O-D pair, a Column Generation Algorithm (CGA) is adopted to exploit the special structures of the model. Based on the known capacity of each link, a simple formula is suggested to calculate the cost for the links having unknown volumes. An indexed cost is introduced to avoid the consideration of unnecessary passing-through-zone paths, and an algorithm for solving the corresponding minimum-cost-path problem is developed. General principles on the design of an object-oriented code are presented, and some useful programming techniques are suggested for this special problem. Some test results on the related models are presented and compared, and different sensitivity analyses are performed based on different scenarios. Finally, several research topics are recommended for future research. / Master of Science
65

Effectiveness of Intersection Advanced Driver Assistance Systems in Preventing Crashes and Injuries in Left Turn Across Path / Opposite Direction Crashes in the United States

Bareiss, Max January 2019 (has links)
Intersection crashes represent one-fifth of all police reported traffic crashes and one-sixth of all fatal crashes in the United States each year. Active safety systems have the potential to reduce crashes and injuries across all crash modes by partially or fully controlling the vehicle in the event that a crash is imminent. The objective of this thesis was to evaluate crash and injury reduction in a future United States fleet equipped with intersection advanced driver assistance systems (I-ADAS). In order to evaluate this, injury risk modeling was performed. The dataset used to evaluate injury risk was the National Automotive Sampling System / Crashworthiness Data System (NASS/CDS). An injured occupant was defined as vehicle occupant who experienced an injury of maximum Abbreviated Injury Scale (AIS) of 2 or greater, or who were fatally injured. This was referred to as MAIS2+F injury. Cases were selected in which front-row occupants of late-model vehicles were exposed to a frontal, near-, or far-side crash. Logistic regression was used to develop an injury model with occupant, vehicle, and crash parameters as predictor variables. For the frontal and near-side impact models, New Car Assessment Program (NCAP) test results were used as a predictor variable. This work quantitatively described the injury risk for a wide variety of crash modes, informing effectiveness estimates. This work reconstructed 501 vehicle-to-vehicle left turn across path / opposite direction (LTAP/OD) crashes in the United States which had been originally investigated in NMVCCS. The performance of thirty different I-ADAS system variations was evaluated for each crash. These variations were the combinations of five Time to Collision (TTC) activation thresholds, three latency times, and two different intervention types (automated braking and driver warning). In addition, two sightline assumptions were modeled for each crash: one where the turning vehicle was visible long before the intersection, and one where the turning vehicle was only visible after entering the intersection. For resimulated crashes which were not avoided by I-ADAS, a new crash delta-v was computed for each vehicle. The probability of MAIS2+F injury to each front row occupant was computed. Depending on the system design, sightline assumption, I-ADAS variation, and fleet penetration, an I-ADAS system that automatically applies emergency braking could avoid 18%-84% of all LTAP/OD crashes. An I-ADAS system which applies emergency braking could prevent 44%-94% of front row occupants from receiving MAIS2+F injuries. I-ADAS crash and injured person reduction effectiveness was higher when both vehicles were equipped with I-ADAS. This study presented the simulated effectiveness of a hypothetical intersection active safety system on real crashes which occurred in the United States, showing strong potential for these systems to reduce crashes and injuries. However, this crash and injury reduction effectiveness made the idealized assumption of full installation in all vehicles of a future fleet. In order to evaluate I-ADAS effectiveness in the United States fleet the proportion of new vehicles with I-ADAS was modeled using Highway Loss Data Institute (HLDI) fleet penetration predictions. The number of potential LTAP/OD conflicts was modeled as increasing year over year due to a predicted increase in Vehicle Miles Traveled (VMT). Finally, the combined effect of these changes was used to predict the number of LTAP/OD crashes each year from 2019 to 2060. In 2060, we predicted 70,439 NMVCCS-type LTAP/OD crashes would occur. The predicted number of MAIS2+F injured front row occupants in 2060 was 3,836. This analysis shows that even in the long-term fleet penetration of Intersection Active Safety Systems, many injuries will continue to occur. This underscores the importance of maintaining passive safety performance in future vehicles. / M.S. / Future vehicles will have electronic systems that can avoid crashes in some cases where a human driver is unable, unaware, or reacts insufficiently to avoid the crash without assistance. The objective of this work was to determine, on a national scale, how many crashes and injuries could be avoided due to Intersection Advanced Driver Assistance Systems (I-ADAS), a hypothetical version of one of these up-and-coming systems. This work focused on crashes where one car is turning left at an intersection and the other car is driving through the intersection and not turning. The I-ADAS system has sensors which continuously search for other vehicles. When the I-ADAS system determines that a crash may happen, it applies the brakes or otherwise alerts the driver to apply the brakes. Rather than conduct actual crash tests, this was simulated on a computer for a large number of variations of the I-ADAS system. The basis for the simulations was real crashes that happened from 2005 to 2007 across the United States. The variations that were simulated changed the time at which the I-ADAS system triggered the brakes (or alert) and the simulated amount of computer time required for the I-ADAS system to make a choice. In some turning crashes, the car cannot see the other vehicle because of obstructions, such as a line of people waiting to turn left across the road. Because of this, simulations were conducted both with and without the visual obstruction. For comparison, we performed a simulation of the original crash as it happened in real life. Finally, since there are two cars in each crash, there are simulations when either car has the I-ADAS system or when both cars have the I-ADAS system. Each simulation either ends in a crash or not, and these are tallied up for each system variation. The number of crashes avoided compared to the number of simulations run is crash effectiveness. Crash effectiveness ranged from 1% to 84% based on the system variation. For each crash that occurred, there is another simulation of the time immediately after impact to determine how severe the impact was. This is used to determine how many injuries are avoided, because often the crashes which still happened were made less severe by the I-ADAS system. In order to determine how many injuries can be avoided by making the crash less severe, the first chapter focuses on injury modeling. This analysis was based on crashes from 2008 to 2015 which were severe enough that one of the vehicles was towed. This was then filtered down by only looking at crashes where the front or sides were damaged. Then, we compared the outcome (injury as reported by the hospital) to the circumstances (crash severity, age, gender, seat belt use, and others) to develop an estimate for how each of these crash circumstances affected the injury experienced by each driver and front row passenger. A second goal for this chapter was to evaluate whether federal government crash ratings, commonly referred to as “star ratings”, are related to whether the driver and passengers are injured or not. In frontal crashes (where a vehicle hits something going forwards), the star rating does not seem to be related to the injury outcome. In near-side crashes (the side next to the occupant is hit), a higher star rating is better. For frontal crashes, the government test is more extreme than all but a few crashes observed in real life, and this might be why the injury outcomes measured in this study are not related to frontal star rating. Finally, these crash and injury effectiveness values will only ever be achieved if every car has an I-ADAS system. The objective of the third chapter was to evaluate how the crash and injury effectiveness numbers change each year as new cars are purchased and older cars are scrapped. Early on, few cars will have I-ADAS and crashes and injuries will likely still occur at roughly the rate they would without the system. This means that crashes and injuries will continue to increase each year because the United States drives more miles each year. Eventually, as consumers buy new cars and replace older ones, left turn intersection crashes and injuries are predicted to be reduced. Long into the future (around 2050), the increase in crashes caused by miles driven each year outpaces the gains due to new cars with the I-ADAS system, since almost all of the old cars without I-ADAS have been removed from the fleet. In 2025, there will be 173,075 crashes and 15,949 injured persons that could be affected by the I-ADAS system. By 2060, many vehicles will have I-ADAS and there will be 70,439 crashes and 3,836 injuries remaining. Real cars will not have a system identical to the hypothetical I-ADAS system studied here, but systems like it have the potential to significantly reduce crashes and injuries.
66

Etude comparative de la notion de "l'homme parfait" chez Mowlânâ Djalâl-Od-Dîn Rûmî-é Balkhî et Alfred de Vigny / The comparative study between Mowlânâ Djalâl-Od-Dîn Rûmî-é Balkhî and Alfred de Vigny on the subject of "perfect man"

Mahdavi Zadeh, Mojgan 30 March 2012 (has links)
De nos jours, nous accordons une place particulière à la littérature Universelle, qui est située au point de croisement du soi et de l’autre, de l’implicite et de l’explicite, de l’intime et du public. En ce qui concerne notre étude comparative entre la vision de Mowlânâ Djalâl Od-Dîn Mohammad Balkhî Rûmî, poète mystique iranien du XIIIème siècle et celle d'Alfred de Vigny, poète stoïcien, romantique et mystique français du XIXème siècle, sur l'Homme Parfait, nous avons tenté à montrer que nos deux Génies, quoique l’un était oriental et l’autre occidental, que l’un était du 13ème siècle et l’autre du 19ème siècle, que leurs religions étaient différentes, que l’un était postérieur à l’autre et ne l’a fort probablement jamais lu, ont des avis quasiment identiques sur l’Homme Parfait. En effet, la pureté et la bonté spirituelle, l’innocence, l’honnêteté, l’amitié, l’amour, et les caractères humbles de l’être humain, ne dépendent point des dimensions spatio-temporelles, ni de l’idéologie et de la civilisation des sujets à traiter, car ce sont des qualités purement humaines qui prennent leur source dans la conscience, le cœur et l’âme et représentent tout le côté divin de l'être. L'Homme Parfait nommé le "vrai Mystique" chez Mowlanâ et le "Paria" chez Alfred de Vigny certifient que certains hommes sont des êtres à part, sortes d’extraterrestres, tout en étant des symboles de l’humanité. Ces gens là, tout à la fois d’ici-bas et d’au-delà, libérés en fait de leur « moi » matériel, sont le pur reflet d’un « moi » divin. Une telle personne peut espérer être sur le bon chemin et pouvoir rester digne de posséder à la fois la face de l’Homme et la face de Dieu. Par conséquent, nous avons simplement envisagé les points communs entre les sujets en question et en tenant compte des notions d'identité et d'altérité, nous nous sommes focalisés sur une paix universelle. / Today the Universal literature has taken a particular place for itself, because this literature is on the cross point of "self" and "other", "implicit" and "explicit", "intimate" and "public". The comparative study between the foresights of Mowlânâ Djalâl-Od- Dîn Mohammad Rûmî-é BalkhÎ, the Iranian mystic poet of the 13th century, and, Alfred de Vigny, the romantic, stoic, and mystic poet of French 19th century, on the subject of "Perfect Man", in spite of the fact that the two men lived six centuries apart, one was in the East and the other one was in the West of the World, their religions were different, and that most likely Vigny had not read Mowlânâ's works, the two poets have almost similar opinions about the "Perfect Man". Normally, the comparative study is conducted to identify, directly or indirectly, the influence of a certain person or doctrine over another person or doctrine; but in this study, our readers or audience will see that the nature of purity, spiritual goodness, innocence, honesty, friendship, love, and sublime human characteristics are neither dependent of time and place, nor they depend on a specific ideology or a special culture, because they have all their roots in the intelligence, heart, and spirit of individuals and are part of Devine aspect of human being.
67

Uticaj temperamenta na nastanak i razvoj zavisnosti od opijata / The influence of temperament on occurrence and development of opiate dependence

Ratković Dragana 28 September 2017 (has links)
<p>Uvod: Temperament predstavlja skup psiholo&scaron;kih osobina, to jest način, brzinu i jačinu umnog i emotivnog reagovanja svojstven pojedincu, odnosno njegovu narav, ćud, prirodu. Savremena istraživanja premorbidnog afektivnog tipa temperamenta, govore u prilog njegovog značaja u etiologiji i kliničkoj evaluaciji bolesti zavisnosti. Cilj: Utvrditi i uporediti temperament kod osoba obolelih od mentalnog poremećaja i poremećaja pona&scaron;anja zbog upotrebe opijata i zdrave populacije. Materijal i metode: Istraživanje je urađeno po tipu studije preseka, i obuhvatalo je 200 ispitanika, podeljenih u dve grupe. Ispitivanu grupu činilo je 100 stabilnih zavisnika od opijata na supstitucionoj terapiji metadonom, starosti od 18 do 40 godina, bez komorbidne bolesti iz kruga psihotičnih poremećaja. U kontrolnu grupu uvr&scaron;teno je 100 zdravih osoba &scaron;to sličnijih sociodemografskih karakteristika sa ispitivanom grupom. Njihov temperament je određivan TEMPS-A upitnikom samoprocene. Rezultati: Utvrđeno je statistički značajno če&scaron;će postojanje dominantog temperamenta kod zavisnika, kao i prisustvo depresivnog, ciklotimnog, razdražljivog i anksioznog temperamenta, koji govore u prilog osnovne razlike između zdrave populacije i populacije sa mentalnim poremećajem i poremećajem pona&scaron;anja zbog upotrebe opijata. Zaključak: Afektivni temperament, kao premorbidna karakteristika ličnosti, ima uticaja na nastanak i razvoj zavisnosti od opijata. Stoga je od značaja da se uzmu u obzir osobine hipertimnog temperamenta kao protektivnog ili depresivnog, ciklotimnog, radražljivog i anksioznog temperamenta kao rizičnih faktora u etiologiji, prevenciji i terapiji bolesti zavisnosti.</p> / <p>Introduction: Temperament is a set of psychological characteristics, ie the speed and strength of mind and emotional reactions peculiar to the individual, or his character, temperament, nature. Modern research of the premorbid affective temperament is in favor of its significance in the etiology and clinical evaluation of substance abuse. The Aim: To determine and compare the temperament of people suffering from mental and behavioral disorders due to use of opioids and healthy population. Materials and Methods: The study was cross-sectional, and 200 subjects were included and divided into two groups. The study group included stable opiate addicts on substitution therapy with methadone, aged 18 to 40 years, without co-morbid psychotic disorders. The Control group consisted of 100 healthy individuals with similar sociodemographic data as the Study group. Their temperament was determined with the TEMPS-A auto-questionnaire. Results: Statistical significance of a dominant temperament was more frequently found in the subjects with opioid dependence, as well as in depressive, cyclothymic, anxious and irritable temperament, which leads to the fundamental differences between a healthy population and a population with mental and behavioral disorders due to the use of opioids. Conclusion: Affective temperament, as a premorbid personality trait, has an impact on the occurence and development of opiate dependence. Therefore, it is essential to take into account the characteristics of a hyperthymic temperament as a protective factor or depressive, cyclothymic, irritable and anxious temperament as risk factors in etiology, prevention and treatment of addiction.</p>
68

Determinação dos enantiômeros da atropina em soluções oftálmicas empregando a cromatografia líquida de alta eficiência com fase estacionária quiral / Determination of atropine enantiomers in ophthalmic solutions by liquid chromatography using a chiral stationary phase

Soares, Renata 08 November 2007 (has links)
Há muitos agentes terapêuticos comercializados sob forma racêmica. Os enantiômeros podem apresentar diferenças significativas nos perfis farmacocinético e farmacodinâmico. O uso do enantiômero puro em formulações farmacêuticas pode resultar em melhor ajuste de dose e menos efeitos adversos. A atropina, um alcalóide natural da Atropa belladonna, é a mistura racêmica de l-hiosciamina e d-hiosciamina. Este fármaco é principalmente utilizado para dilatar a pupila e como um antiespasmódico. Para quantificar estes enantiômeros, foram desenvolvidos métodos analíticos utilizando a cromatografia líquida de alta eficiência (CLAE) com as fases estacionárias quirais Chiralcel-OD® e Chiral-AGP®. Para quantificar estes enantiômeros em soluções oftálmicas, foi realizada a validação com sucesso de um método por CLAE, empregando uma coluna Chiral-AGP®, a 20°C. A fase móvel foi uma solução tampão fosfato (contendo 10 mM de 1-octanosulfonato de sódio e 7,5 mM de trietilamina, ajustada para pH 7,0 com ácido fosfórico) e acetonitrila (99:1 v/v). A vazão foi de 0,6 mL/min, com detecção ultravioleta em 205 nm. No intervalo de concentração de 14,0 &#181;g/mL a 26,0 &#181;g/mL, o método é linear (r > 0,9999), exato (100,1% - 100,5%) e preciso (RSDsistema &#8804; 0,6%; RSDintra-dia &#8804; 1,1%; RSDentre-dias &#8804; 0,9%). O método é específico e os testes de validação asseguram que as soluções de padrão e amostra são estáveis até 72 horas. O planejamento fatorial assegura a robustez com variação de ±10% nos componentes da fase móvel e 2°C na temperatura da coluna. / There are many therapeutic agents commercialized under racemic form. The enantiomers can show significant differences in the pharmacokinetic and pharmacodynamic profiles. The use of pure enantiomer in pharmaceutical formulations can result in better adjustment of dose and less adverse effects. Atropine, an alkaloid of the Atropa belladonna, is a racemic mixture of l-hyoscyamine and d-hyoscyamine. This drug is mainly used to dilate the pupil and as an antispasmodic agent. To quantify these enantiomers analytical methods were developed, using high performance liquid chromatography (HPLC) with chiral stationary phases Chiralcel OD&#174; and Chiral AGP&#174;. To quantify these enantiomers in ophthalmic solutions the validation of a HPLC method was performed using a Chiral AGP&#174; column at 20°C. The mobile phase consisted of a buffered phosphate solution (containing 10 mM 1-octanesulfonic acid sodium salt and 7.5 mM triethylamine, adjusted to pH 7.0 with ortho-phosphoric acid) and acetonitrile (99:1 v/v). The flow rate was 0.6 mL/min, with ultraviolet detection at 205 nm. In the concentration range from 14.0 mg/mL to 26.0 mg/mL, the method is linear (r > 0.9999), exact (100.1% - 100.5%) and precise (RSDsystem &#8804; 0.6%; RSDintra-day &#8804; 1.1%; RSDinter day &#8804; 0.9%). The method is specific and the validation tests assure that standard and sample solutions are stable for up to 72 hours. The factorial design assures the robustness with variation of ± 10% in the mobile phase components and 2°C of column temperature.
69

Aperfeiçoamento da sequência O/OD*(EP)DP para branqueamento de celulose kraft de eucalipto / Improvement of O/OD*(EP)DP sequence for bleaching of eucaliptus kraft cellulose

Pimenta, Leonardo Mendonça 02 July 2010 (has links)
Made available in DSpace on 2015-03-26T14:01:03Z (GMT). No. of bitstreams: 1 texto completo.pdf: 281669 bytes, checksum: adf965188180a1e5e199a4f2184132cd (MD5) Previous issue date: 2010-07-02 / A eucaliptus kraft pulp of a Brazilian mill, extracted from the first washing stage before oxygen delignification, was bleached at more than 50 different bleaching conditions with the target to reach the optimum cost. Considering the O/OD*(EP)DP sequence, the best result was reached carrying out D* stage with soft conditions, preserving hexenuronic acids in the pulp and minimizing the chlorine dioxide consumption by products from its hydrolysis (furan carboxylic acids). Twenty one percent cost savings, in relation to current mill conditions, were achieved using pH 4,5, kappa factor 0,16 and 70 ºC temperature at D*stage, pH 10,3 and 5,5 at (EP) and D1 stages, respectively. Strength properties of this pulp were not significantly affected if compared with reference pulp produced under current mill conditions. The OX and AOX contents of this pulp were significantly reduced in relation to the reference. When applied at the mill, these optimum conditions were responsible for reducing 5 kg/adt active chlorine consumption. / Uma polpa kraft de eucalipto de uma fábrica do Brasil, coletada antes do pré branqueamento, foi submetida a mais de 50 diferentes condições de branqueamento em laboratório com o objetivo de otimizar os custos operacionais. Considerando a sequência O/OD*(EP)DP, o arranjo ótimo encontrado foi realizar o estágio D* em condições brandas, no intuito de preservar os ácidos hexenourônicos na polpa e minimizar o consumo de dióxido de cloro pelos subprodutos de sua hidrólise (ácidos furacarboxílicos). Com o pH de 4,5, fator kappa de 0,16 e temperatura de 70 ºC no estágio D*, associado a um pH de 10,3 e 5,5 nos estágios (EP) e D1, respectivamente, houve uma redução de 21% no custo de reagentes. Não foram observados impactos significativos nas propriedades físicas da polpa e, em função do menor consumo de dióxido de cloro, houve redução do teor de OX e AOX. Estas condições, quando praticadas na fábrica, reduziram o consumo específico de cloro ativo em cerca de 5 kg/tSA.
70

Determinação dos enantiômeros da atropina em soluções oftálmicas empregando a cromatografia líquida de alta eficiência com fase estacionária quiral / Determination of atropine enantiomers in ophthalmic solutions by liquid chromatography using a chiral stationary phase

Renata Soares 08 November 2007 (has links)
Há muitos agentes terapêuticos comercializados sob forma racêmica. Os enantiômeros podem apresentar diferenças significativas nos perfis farmacocinético e farmacodinâmico. O uso do enantiômero puro em formulações farmacêuticas pode resultar em melhor ajuste de dose e menos efeitos adversos. A atropina, um alcalóide natural da Atropa belladonna, é a mistura racêmica de l-hiosciamina e d-hiosciamina. Este fármaco é principalmente utilizado para dilatar a pupila e como um antiespasmódico. Para quantificar estes enantiômeros, foram desenvolvidos métodos analíticos utilizando a cromatografia líquida de alta eficiência (CLAE) com as fases estacionárias quirais Chiralcel-OD® e Chiral-AGP®. Para quantificar estes enantiômeros em soluções oftálmicas, foi realizada a validação com sucesso de um método por CLAE, empregando uma coluna Chiral-AGP®, a 20°C. A fase móvel foi uma solução tampão fosfato (contendo 10 mM de 1-octanosulfonato de sódio e 7,5 mM de trietilamina, ajustada para pH 7,0 com ácido fosfórico) e acetonitrila (99:1 v/v). A vazão foi de 0,6 mL/min, com detecção ultravioleta em 205 nm. No intervalo de concentração de 14,0 &#181;g/mL a 26,0 &#181;g/mL, o método é linear (r > 0,9999), exato (100,1% - 100,5%) e preciso (RSDsistema &#8804; 0,6%; RSDintra-dia &#8804; 1,1%; RSDentre-dias &#8804; 0,9%). O método é específico e os testes de validação asseguram que as soluções de padrão e amostra são estáveis até 72 horas. O planejamento fatorial assegura a robustez com variação de ±10% nos componentes da fase móvel e 2°C na temperatura da coluna. / There are many therapeutic agents commercialized under racemic form. The enantiomers can show significant differences in the pharmacokinetic and pharmacodynamic profiles. The use of pure enantiomer in pharmaceutical formulations can result in better adjustment of dose and less adverse effects. Atropine, an alkaloid of the Atropa belladonna, is a racemic mixture of l-hyoscyamine and d-hyoscyamine. This drug is mainly used to dilate the pupil and as an antispasmodic agent. To quantify these enantiomers analytical methods were developed, using high performance liquid chromatography (HPLC) with chiral stationary phases Chiralcel OD&#174; and Chiral AGP&#174;. To quantify these enantiomers in ophthalmic solutions the validation of a HPLC method was performed using a Chiral AGP&#174; column at 20°C. The mobile phase consisted of a buffered phosphate solution (containing 10 mM 1-octanesulfonic acid sodium salt and 7.5 mM triethylamine, adjusted to pH 7.0 with ortho-phosphoric acid) and acetonitrile (99:1 v/v). The flow rate was 0.6 mL/min, with ultraviolet detection at 205 nm. In the concentration range from 14.0 mg/mL to 26.0 mg/mL, the method is linear (r > 0.9999), exact (100.1% - 100.5%) and precise (RSDsystem &#8804; 0.6%; RSDintra-day &#8804; 1.1%; RSDinter day &#8804; 0.9%). The method is specific and the validation tests assure that standard and sample solutions are stable for up to 72 hours. The factorial design assures the robustness with variation of ± 10% in the mobile phase components and 2°C of column temperature.

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