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Nuevos sistemas supramoleculares: compuestos de inclusión de matrices binarias de urea y tioureaMerchan Vélez, Juan Eugenio January 2002 (has links)
Doctor en Química / Esta tesis constituye una incursión y contribución al conocimiento de la química supramolecular
y de la química de las interacciones sutiles en el ámbito de compuestos polimoleculares
derivados de las matrices binarias de urea y tiourea.
Se sintetizaron y caracterizaron los compuestos de inclusión de las matrices aniónicas
urea/cloruro, urea/bromuro, urea/yoduro, tiourea/cloruro, tiourea/bromuro, tiourea/yoduro
incorporando como huésped el catión diquinuclidonio. Las matrices están formadas por unidades
de urea o tiourea que se unen entre sí mediante puentes de hidrógeno y puentes de halógeno. Las
uniones entre las matrices y los huéspedes son débiles, de naturaleza no específica.
Los compuestos obtenidos se caracterizaron a través de las técnicas difracción de rayos-X en
muestras policristalinas y monocristal, análisis térmico diferencial (DTA), calorimetría
diferencial de barrido (DSC), termogravimetría (TG),
1
H y
13
C-RMN en solución y
1
H–RMN
en sólido, espectroscopía infrarroja e impedancia compleja. Todos estos compuestos presentan
propiedades estructurales conmensuradas. Las sustancias obtenidas en general poseen estructuras
características diferentes de los clatratos típicos, excepto aquéllas de las matrices tiourea/cloruro
y tiourea/bromuro que presentan canales hexagonales. Tiourea/yoduro, urea/bromuro y
urea/yoduro presentan estructuras laminares. Urea/cloruro posee una estructura particular con
una matriz de tipo bicanal.
Estimaciones de las propiedades conductoras de los compuestos sintetizados demostraron
que estos se comportan como poco conductores y anisótropos. La conductividad varía de
acuerdo al ambiente en que se realicen los experimentos, esto es, vacío, humedad y temperatura.
Como valores extremos se obtuvieron 1.13 x 10
-4
para urea-bromuro/diquinuclidonio en sistema
abierto a 77ºC y 4.82 x 10
-11
para tiourea-bromuro/diquinuclidonio al vacío y 25ºC, ambas
medidas en pastillas.
Los compuestos sintetizados no descomponen antes de la fusión y la destrucción de la
matriz y pérdida de huésped ocurre generalmente en ese punto.
Todos los compuestos obtenidos en esta tesis muestran un efecto motriz muy particular al
romperse la matriz en presencia de solventes como agua o dimetilsulfóxido, producido por el
efecto de abandono acelerado del huésped. Lo anterior es acompañado de la aparición de un
color rosado en presencia de fenolftaleina como indicador.
También se sintetizó y caracterizó el compuesto binario de tiourea con quinuclidina cuya
estructura no estaba reportada, se trata de una estructura típica de compuesto binario tipo túnel
de tiourea.
Se pudo demostrar experimentalmente por
13
C CP-MAS un equilibrio al interior de la
matriz de tiourea de un compuesto binario a través de un desplazamiento de huéspedes, sin
ocurrir la destrucción de la matriz.
Intentos de síntesis de compuestos de inclusión ternarios halogenados de urea y tiourea con
fosfinas aromáticas y cíclicas no aromáticas fueron infructuosos, lo mismo aconteció con éteres
corona litiados.
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Právo a ochrana lékaře / The law and the protection of a physicianCyrányová, Lucie January 2016 (has links)
This master thesis deals with the medical law specifically protection of doctors that Czech legal code provides. The goal of this thesis is to highlight doctor's rights in relation to patients. My thesis contains nine chapters which are divided into subsections clearly. First I defined legislation of medical law and doctors. In the next part I focus on the issue who can practice as a doctor and what conditions he/she has to fulfill. The new definition of the appropriate professional level is very important for the profession of doctor. This procedure is called lege artis. The entirely third chapter devotes this issue - I also deal with opinions of experts who assess whether the provided medical service fulfills all aspects of the lege artis. Further chapter describes the relationship between doctor and patient and the changes that have been observed in recent years. Following chapters are the most important ones. They outline the specific rights and different ways how to protect doctors. I tried to present legal instruments which are not primarily created to protect doctors however they provide this protection and are very important for their profession. I put an emphasis on issues of compulsory confidentiality and in particular on exceptions when a doctor can disclose information about a patient...
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An investigation of the heartsink patientMathers, Nigel Joseph January 1993 (has links)
No description available.
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Cinética y mecanismos de reacción de radicales estables con sustratos de interés biológicoAliaga Vidal, Carolina del Pilar January 2000 (has links)
Doctor en Química
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Breaking the silence : toward a theory of women's doctoral persistenceKerlin, Roberta-Anne 24 May 2017 (has links)
In recent years educational researchers have expressed a growing concern about both
increased rates of attrition from doctoral programs and the increased time required to
compete the doctorate. Many researchers have estimated that upwards of 50% of doctoral
students withdraw from their programs prior to completion of degree requirements.
Although women’s rates of enrollment have grown significantly over the past decade there
is also much evidence to show that women withdraw from doctoral programs of study at
higher rates than men. Given these trends there is good reason to examine more closely,
factors that influence women’s doctoral degree progress.
This study provides an in-depth qualitative examination of the challenges women encounter
in pursuing the Ph.D., and the meanings they attribute to their experiences, with the
purpose of identifying critical factors that influence women’s doctoral persistence. The
study breaks new methodological ground by demonstrating how the Internet, often thought
to be a cold and impersonal medium, can be used to conduct in-depth personal interviews
that are rich in meaning despite separation of interviewer and interviewees in both place and
time. Utilizing grounded theory methodology for analyzing the data, five women Ph.D.
candidates and two recent Ph.D. recipients were interviewed over the course of one year
(1995). A critical feminist perspective provides the theoretical framework for understanding
the women’s learning experiences within the contexts of their institutional and departmental
milieux.
Findings relating to women’s doctoral persistence emerge through an analysis of electronic
mail transcripts and face-to-face interviews. Central to the findings is the illumination of a
complex interaction of personal, social and institutional factors that both enhance and
detract from women’s doctoral persistence. Eleven elements of a theory of women’s
doctoral persistence are put forward. The benefits and limitations of using electronic networks to conduct qualitative inquiry are examined. / Graduate
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The effect of the question "Is there anything else?" asked at the end of a patient consultation in a family practiceWelch, Kirsten Margaret 10 March 2011 (has links)
MFamMed, Faculty of Health Sciences, University of the Witwatersrand / The effect of asking the question “Is there anything else?” toward the end of selected
consultations was assessed. A study was conducted using a sample of 200 patients
from a Johannesburg general family practice, randomly allocated into intervention
and control groups. Details of patient demographics and of the consultations in both
groups were recorded. Patients from the study group were asked “Is there anything
else?” at the transition to closure of the consultation. The responses elicited were
recorded and compared to issues raised spontaneously by patients in the control
group at the same stage of the consultation. 43% of the patients in the study group
used the opportunity to introduce new issues not yet discussed. 26% of the patients
in the control group asked questions at the same point in the consultation. The
problems raised were similar in each group, as was the time added to the
consultation. This would suggest that patients will raise more issues if given the
opportunity than they may have raised unprompted. Dealing with these issues may
make the consultation longer, but may prevent unnecessary future visits and
investigations.
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Perceptions of Physician Empathy: Effects of Demographic FeaturesLetizia, Jessica January 2014 (has links)
Thesis advisor: Andrea Heberlein / Expressions of empathy are considered a core component of a physician’s treatment of their patients. It is imperative to the establishment of open communication, which aids in facilitating a good interpersonal relationship, exchanging information and making treatment-related decisions. Although empathy is widely viewed as essential, it is also commonly viewed as burdensome. We propose that empathy can be divided based on the characteristics in which we evaluate another’s mind. Previous research indicates that we attribute mental capacities based on two distinct dimensions: experience and agency, described as the capacity to feel and the capacity to act, respectively. By dividing physician empathy into an understanding of a patient’s feelings and an understanding of a patient’s goals, it may be possible to extract what we are assuming to be the emotionally taxing component by focusing just on the patient’s agency. 270 participants were surveyed regarding their opinions of their physician’s communication in an attempt to identify trends within demographic populations for preferences for goal-directed or emotional empathy. Results indicate significant effects of age, gender and combined income. As age and combined income increase, appreciation for agency-related communication decreases. Females also expressed significantly higher appreciation for an experience-related style of communication. / Thesis (BA) — Boston College, 2014. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: College Honors Program. / Discipline: Psychology.
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Time to the doctorate : a study of three modelsTornquist, Emanuel M. 05 1900 (has links)
No description available.
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The role of information in medical consultationFrederikson, Lesley G. January 1992 (has links)
No description available.
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Research-related Coursework and Research Experiences in Doctor of Pharmacy ProgramsSherbeck, Victoria, Murphy, John January 2014 (has links)
Class of 2014 Abstract / Specific Aims: Our goal was to identify the extent and type of research requirements in Doctorate of Pharmacy programs in the United States and Puerto Rico. Regular and associate institutional school members of the American Association of Colleges of Pharmacy (AACP) were eligible to complete this study. Methods: Online questionnaires were distributed through email in three waves. Questions consisted of demographic questions, and questions about the type and extent of research requirements each school offers. Main Results: Some type of research project was required in seven schools (25.9%) during the course of their PharmD curriculum. Of the 27 schools completing the questionnaire, 55% indicated they required research methods, 78% required statistics, and 100% required drug information/literature evaluation courses during their PharmD curriculum. Conclusion: The majority of colleges provide research-related coursework for their students in PharmD programs. Roughly a quarter of schools require some form of research project be completed prior to graduation, with a large portion offering some form of research experience or elective with research opportunities.
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