Axisymmetric Drop Shape Analysis (ADSA) and Lung Surfactant

The objective of this thesis was to further develop a methodology for surface tension measurement called Axisymmetric Drop Shape Analysisn(ADSA) and to adapt it to studies of lung surfactants, i.e. the material that coats and facilitates the functioning of the lungs of all mammals. The key property of a functioning lung surfactant is its surface tension, which can reach extremely low values. Such values are difficult to measure; but a certain configuration of ADSA, using a constrained sessile drop (ADSA--CSD), is capable of performing such measurements. Clinically, lung surfactant films can be altered from both sides, i.e. from the airspace as well as from the bulk liquid phase that carries the film. Therefore, being able to access the interface from both sides is important. Here, ADSA--CSD was redesigned to be used as a micro film balance allowing access to the interface from both gas- and liquid-side. This allows deposition from the gas side as well as complete exchange of the bulk liquid phase. The new design was used to study lung surfactant inhibition and inhibition reversal. A dynamic compression-relaxation model (CRM) was developed to describe the mechanical properties of lung surfactant films by investigating the response of surface tension to changes in surface area. The model evaluates the quality of lung surfactant preparations -- beyond the minimum surface tension value -- and calculates the film properties, i.e. elasticity, adsorption and relaxation, independent of the compression protocol. The accuracy of the surface tension measurement can depend on drop size. A detailed analysis of drop shapes and accuracy of measured surface tension values was performed using a shape parameter concept. Based on this analysis, the design of ADSA--CSD was optimized to facilitate more accurate measurements. The validity analysis was further extended to the more conventional pendant drop setup (ADSA--PD). An overall upgrade of both hardware and software of ADSA--CSD, together with extensive numerical work, is described and applied to facilitate a more efficient operation. Finally, it is noted that the ADSA--CSD setup developed here can be used for a wide range of colloid and surface chemical applications.Ph

The Temple of Ramesses II in Abydos. Volume 2

Of all the enormous monuments throughout Egypt and Nubia that Ramesses II (the Great; ca. 1279–1212 BCE) left behind, his temple at Abydos, built early in his reign, stands as one of his most elegant monuments, with its simple architectural layout and dramatic and graceful painted relief scenes. Though best known for its dramatic reliefs depicting the battle of Kadesh, the temple also offers a wealth of information about religious and social life in ancient Egypt. It reflects, for example, the strenuous efforts of the early Ramessides to reestablish the Osiris cult in Egypt—and particularly at Abydos—in the aftermath of the Amarna period. Over a seven-year period, the authors of The Temple of Ramesses II in Abydos conducted a field project with the aim of producing an up-to-date and comprehensive architectural, photographic, and epigraphic record of the temple. This lavish volume, This lavish volume, the second of two documenting their results, presents miscellaneous elements of the temple, including the pillars, as well as translations of the inscriptions found in the temple. Volume 1, "Wall Scenes," (available here) contains more than two hundred detailed line drawings—accurately rendered according to modern epigraphical standards—of the temple's carved relief scenes, placed alongside their corresponding full-color photographs. The result is a masterpiece of modern epigraphic research and publication.</jats:p

Axisymmetric Drop Shape Analysis (ADSA) and Lung Surfactant

The objective of this thesis was to further develop a methodology for surface tension measurement called Axisymmetric Drop Shape Analysisn(ADSA) and to adapt it to studies of lung surfactants, i.e. the material that coats and facilitates the functioning of the lungs of all mammals. The key property of a functioning lung surfactant is its surface tension, which can reach extremely low values. Such values are difficult to measure; but a certain configuration of ADSA, using a constrained sessile drop (ADSA--CSD), is capable of performing such measurements. Clinically, lung surfactant films can be altered from both sides, i.e. from the airspace as well as from the bulk liquid phase that carries the film. Therefore, being able to access the interface from both sides is important. Here, ADSA--CSD was redesigned to be used as a micro film balance allowing access to the interface from both gas- and liquid-side. This allows deposition from the gas side as well as complete exchange of the bulk liquid phase. The new design was used to study lung surfactant inhibition and inhibition reversal. A dynamic compression-relaxation model (CRM) was developed to describe the mechanical properties of lung surfactant films by investigating the response of surface tension to changes in surface area. The model evaluates the quality of lung surfactant preparations -- beyond the minimum surface tension value -- and calculates the film properties, i.e. elasticity, adsorption and relaxation, independent of the compression protocol. The accuracy of the surface tension measurement can depend on drop size. A detailed analysis of drop shapes and accuracy of measured surface tension values was performed using a shape parameter concept. Based on this analysis, the design of ADSA--CSD was optimized to facilitate more accurate measurements. The validity analysis was further extended to the more conventional pendant drop setup (ADSA--PD). An overall upgrade of both hardware and software of ADSA--CSD, together with extensive numerical work, is described and applied to facilitate a more efficient operation. Finally, it is noted that the ADSA--CSD setup developed here can be used for a wide range of colloid and surface chemical applications.Ph

The Temple of Ramesses II in Abydos Volume 3

Of all the enormous monuments throughout Egypt and Nubia that Ramesses II (the Great; ca. 1279–1212 BCE) left behind, his temple at Abydos, built early in his reign, stands as one of his most elegant, with its simple architectural layout and dramatic and graceful painted relief scenes. Though best known for its dramatic reliefs depicting the battle of Kadesh, the temple also offers a wealth of information about religious and social life in ancient Egypt. It reflects, for example, the strenuous efforts of the early Ramessides to reestablish the Osiris cult in Egypt—and particularly at Abydos—in the aftermath of the Amarna period. Building on the comprehensive photographic and epigraphic documentation of the temple presented in The Temple of Ramesses II at Abydos volumes 1 (Wall Scenes) and 2 (Pillars, Niches, and Miscellanea), volume 3 (Architectural and Inscriptional Features) offers a detailed analysis of the overall architectural layout and decorative program of the temple and its symbolism. This discussion approaches the religious history of the site through its archaeology, its inscriptions—both planned and secondary (graffiti)—and its situation in the complex religious landscape of Abydos. Of particular interest are the temple’s role as a staging point for the great Osiris Festival and its procession, among the most important of all ritual events in the Egyptian religious calendar during the Ramesside period; the promotion of an active, unbound form of Osiris; and the evidence for important cult activities that took place on the rooftop of the temple, the presence of which is documented today by the staircase that accessed it from Court B.</jats:p

Effects of pre-operative isolation on postoperative pulmonary complications after elective surgery: an international prospective cohort study

We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05-1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4-7 days or >= 8 days of 1.25 (1.04-1.48), p = 0.015 and 1.31 (1.11-1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care