Kristallisation, Modifikation und Adsorptionseigenschaften von Calciumcarbonat sowie Untersuchung eines oszillierenden Kristallisationssystems

Es konnte mit Hilfe eines modularen Kristallisationsreaktors die Synthese der wasserfreien Polymorphe des Calciumcarbonats und von Mg-ACC realisiert werden. Amorphes Calciumcarbonat (ACC) konnte bisher nicht in einem kontinuierlichen Prozess gewonnen werden. Es wurde daher im Rahmen dieser Arbeit ein Weg gefunden, auch ACC mittels des Kristallisationsreaktors kontinuierlich ohne kristalline Phasen zu synthetisieren und umfassend zu charakterisieren. Um die Lösungsenthalpien der wasserfreien Calciumcarbonate mit Nano-Calcit zu vergleichen, der im Gegensatz zu makroskopischen Calcit eine wesentlich größere Oberfläche aufweist, wurde nanopartikulärer Calcit hergestellt. Zusammen mit den anderen kristallinen wasserfreien Polymorphen wurde er kalorimetrisch analysiert. In einem Projekt mit der Firma Schaefer Kalk sollte die Adsorption von Biomolekülen an Calciumcarbonaten untersucht werden. Dabei wurde ein Verfahren für die selektive Trennung von DNA und einem Modellprotein erarbeitet. Ein weiterer Teil dieser Arbeit bestand darin, ein oszillierendes Kristallisationssystem zu untersuchen. Diese Kristallisationssysteme sind bisher kaum beschrieben worden. Das Sturmglas wurde Ende des 19. Jahrhunderts als Messinstrument zur Wettervorhersage verwendet. Seither ist die Funktionsweise nicht aufgeklärt und wird mit zahlreichen parawissenschaftlichen Phänomenen in Zusammenhang gebracht. Die Frage, ob und wie das Sturmglas funktioniert, ist bis heute nicht abschließend geklärt. Im Rahmen dieser Arbeit wurde daher ein Sturmglas auf seine Zusammensetzung und Funktion hin analysiert

Running on Empty: Of Hypopinealism and Human Seasonality

The pineal hormone melatonin is the natural transducer of the environmental light-dark signal to the body. Although the responsiveness to photoperiod is well-conserved in humans, only about 25 percent of the human population experiences seasonal changes in behavior. As a consequence, humans seem to have adapted-at least partly-to the seasonal changes in day length. The aim of the study was to demonstrate that the individual melatonin deficit marker DOC (degree of pineal calcification) is related to variation of seasonal phenomena in humans. Out of 3,011 patients in which cranial computer tomography (cCT) was performed for diagnostic reasons, 97 consecutive "healthy" subjects (43 female, 54 male; age 18-68 yrs, mean ± SD: 35.0 ± 13.1) were included. Exclusion criteria were pathological finding in cCT, acute/chronic illness including alcohol/drug abuse, shift work, and medication, which are known to influence melatonin excretion. The degree of pineal calcification (DOC) was semiquantitatively determined using the previously validated method. The Seasonal Pattern Assessment Questionnaire (SPAQ) was performed in a telephone interview. Twenty-six subjects fulfilled the criteria for seasonal affective disorder (SAD) or subsyndromal (S) SAD. Seasonality was more pronounced in women than in men (SPAQ seasonality score: 7.8 ± 4.0 vs. 4.9 ± 4.5; p = 0.001) and negatively and significantly associated with age (r = -0.178; p = 0.04). The subjective sleep length significantly varied between seasons (one-way repeated measures ANOVA: F = 45.75; p < 0.0001), with sleep during winter being 53 min (± 70 min) longer than during summer. Controlling for age, the total seasonality score was negatively and significantly associated with DOC (r(94) = -0.214; p = 0.036). Data confirm earlier studies with respect to distribution of seasonality with sex and age. The survival of seasonality in the sleep length of people living in an urban environment underlines functionality of the circadian timing system in modern societies. Moreover, data confirm for the first time that diminished experience of seasonality in behavior is associated with a reduced individual capacity to produce melatonin

“Breathing” in Adsorbate-Responsive Metal Tetraphosphonate Hybrid Materials

The structures of various layered calcium tetraphosphonates (CaH6DTMP; H8DTMP=hexamethyl- tetrakis(methylenephosphonic acid)), have been determined. Starting from CaH6DTMP·2H2O, thermal treatment and subsequent exposure to NH3 and/or H2O vapors led to four new compounds that showed high storage capacity of guest species between the layers (up to ten H2O/NH3 molecules) and a maximum volume increase of 55%. The basic building block for these phosphonates consists of an eight-membered ring chelating Ca2+ through two phoshonate groups, and the organic ligand is located within the layers, which are held together by hydrogen bonds. The structural analysis revealed that the uptake/removal of guest species (H2O and NH3) induces significant changes in the framework not only by changing the interlayer distances but also through important conformational changes of the organic ligand. An anisotropic breathing motion could be quantified by the changes of the unit-cell dimensions and ligand arrangements in four crystalline derivatives. Complete characterization revealed the existence of interconversion reactions between the different phases upon gas uptake and release. The observed behavior represents, to the best of our knowledge, the first example of a breathing-like mechanism in metal phosphonates that possess a 2D topology

Pineal Calcification and Seasonality in Humans

Einleitung: 25 Prozent der Normalbevölkerung verspüren im Winter ein erhöhtes Schlafbedürfnis und einen gesteigerten Appetit auf Kohlehydrate. Diese sogenannte Saisonalität ist eine Analogie zum Winterschlaf bei Tieren und wird in ihrer pathologischen Form als saisonal affektive Störung (SAD) bezeichnet. Die Anpassung der Melatoninsekretion an die jahreszeitabhängige Veränderung der Nachtlänge, welche bei Säugetieren Verhaltensweisen wie saisonales Brüten und Winterschlaf triggert, ist möglicherweise an der Pathogenese der saisonal affektiven Störung beteiligt. Aussagen über eine Einschränkung der individuellen Melatoninproduktionskapazität können anhand der Bestimmung des Verkalkungsgrades (Degree of Pineal Calcification - DOC) der Glandula pinealis gemacht werden. Ziel der Studie war der Nachweis eines negativen Zusammenhangs zwischen dem DOC und Saisonalität. Patienten und Methoden: Von 3011 Patienten, bei denen aus diagnostischen Gründen eine cCT-Untersuchung durchgeführt wurde, wurden 99 "gesunde" Probanden eingeschlossen, die telefonisch den Seasonal- Pattern-Assessment-Questionnaire beantworteten. Einschlusskriterien waren: Alter zwischen 18 und 80 Jahren, cCT ohne pathologischen Befund, keine akuten oder chronischen Erkrankungen sowie keine melatoninbeeinflussenden Medikamente (z.B. ß-Blocker, Antidepressiva). Auf den cCT-Bildern wurden Größe, Verkalkungsanteil und maximale Dichte der Glandula pinealis bestimmt und der DOC aus den gewonnenen Daten berechnet. Ergebnisse: 26 Probanden (26,3%) erfüllten die Kriterien einer SAD oder deren subsyndromalen Form (S-SAD). Der mittlere DOC der Probanden mit einer SAD- oder S-SAD-Diagnose (m = 0,35, SD = 0,29) war signifikant niedriger als der DOC der Probanden ohne eine SAD/ S-SAD (m = 0,50, SD = 0,32) (p = 0,044). Außerdem war die Zunahme der Winterschlafdauer gegenüber der Sommerschlafdauer der SAD und S-SAD-Probanden (1,3h) signifikant größer als bei Probanden ohne saisonale Phänomene (0,7h) (p = 0,021). Schlussfolgerungen: Ein niedriger DOC als ein Marker für eine unbeeinträchtigte intraindividuelle Melatoninsekretionskapazität ist mit Saisonalität assoziiert.Introduction: During winter, 25% of the general population experiences an increased need to sleep as well as an increased craving for foods rich in carbohydrates. This so-called seasonality in humans is analogous to winter hibernation in animals and, when pathogenic, is termed Seasonal Affective Disorder (SAD). Seasonal changes of day/night cycles affect the secretion of melatonin which, in turn, triggers breeding and hibernation in animals. It is believed that SAD could be linked to such seasonal variations in melatonin production. Evidence about the reduction of individual melatonin production capacity can be seen by measuring the Degree of Pineal Calcification (DOC) of the Glandula pinealis. The goal of the study was to show a negative correlation between DOC and SAD. Patients and Methods: Of 3,011 patients who had undergone a cCT examination for various diagnostic purposes, 99 were chosen as "healthy" study probands to complete a Seasonal-Pattern-Assessment- Questionnaire by telephone. Study inclusion criteria were: age between 18 and 80 years, cCT without pathological findings, no accute or chronic illnesses, and no consumption of medications that affect melatonin levels (e.g., ß-Blockers, antidepressives). Using the cCT images, the size, amount of calcification, and maximum density of the Glandula pinealis were measured and the DOC was calculated. Results: Twenty-six (26) probands (26.3%) fulfilled the criteria for having either SAD or a sub-syndromal form of SAD (S-SAD). The median DOC of the probands diagnosed with either SAD or S-SAD (m = .35, SD = .29) was significantly lower than the DOC of the probands without SAD/S-SAD (m = .50, SD = .32, p = .044). In addition, SAD/S-SAD probands had a significantly higher increase in sleep during the winter versus summer as compared to probands without SAD/S-SAD (.7 h) (p = .021). Conclusions: A lower Degree of Pineal Calcification (DOC) as a marker for unimpaired, individual melatonin secretion capacity is associated with seasonality

Auslaendische Direktinvestitionen in der Automobilindustrie Ostmitteleuropas: Untersuchung der Direktinvestitionen in Polen, Ungarn, der Tschechischen und der Slowakischen Republik

Available from Bibliothek des Instituts fuer Weltwirtschaft, ZBW, Duesternbrook Weg 120, D-24105 Kiel B 285037 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Relationship between the family and community health care model in the Chilean public primary care, and patients’ satisfaction on how they were treated in 2015; A nationwide study

Thesis (Master's)--University of Washington, 2017Background: Primary care-based healthcare systems are essential for every nation. In 2005, Chile embraced the Family and Community’ Comprehensive Health Care Model (or MAIS) to strengthen the primary care and started to measure its development in 2015 using the “MAIS” assessment tool, created for this purpose. One of the expected outcomes of this model is a higher satisfaction with the interactions with the staff and since 2014, a nationwide survey called TU-APS, measures it for the complete public health care system. The current study aims to establish if a relationship exists between the family-centered health care model in the Chilean public healthcare model, as measured by the MAIS tool, and its user’s satisfaction, measured by the TU-APS. Sample: using 2015 countrywide data, the sample considers 438 large General Urban Centers (GUC), 46 General Rural Centers (GRC) from concentrated areas, and 19 Community Hospitals (CH), obtaining data from 503 centers. Methods: In this secondary data analysis, a cross- sectional non-experimental design was in place, using data already collected by the Ministry of Health. Results: According to the TU-APS national survey results, in average, the users of the primary care in Chile evaluated very positively how they are treated in their encounters with the staff (In as scale from 1 to 7,median of 6.453,95% CI 6.424- 6.481). For the MAIS assessment, in a 1 to 100 scale, a median of 55.57 (95% CI 54.2-57.0) showed a normal distribution. Differences between the type of center and the TU-APS national survey (Kruskal-Wallis test, Chi2=24.747, p<0.001) and the MAIS assessment was found (Chi-square=22.315, p<0.001), but only because of the difference between the CH and the other two groups. When the correlation between the TU-APS survey and the MAIS assessment was tested, a small inverse relation was found (Spearman Rho, r= -0.1119, p = 0.0117), i.e. the highest the MAIS evaluation, the lower the results in the TU-APS survey. Possible causes for these findings are discussed. Conclusions: These results don’t confirm the expected relation between the patients’ satisfaction and the advancement of the MAIS model in the Chilean primary care. This could have implications for policies evaluating primary care patient’s satisfactio