Miniemulsionen als räumliche Begrenzungen : Synthese von Polymer-Hydroxylapatit-Nanopartikeln, bio-inspirierten Nanokapseln und Polymer-Einzelkettenpartikeln

In der vorliegenden Arbeit wurden Miniemulsionen als räumliche Begrenzungen für die Synthese von unterschiedlichen funktionellen Materialien mit neuartigen Eigenschaften verwendet. Das erste Themengebiet umfasst die Herstellung von Polymer/Calciumphosphat-Hybridpartikeln und –Hybridkapseln über die templatgesteuerte Mineralisation von Calciumphosphat. Die funktionalisierte Oberfläche von Polymernanopartikeln, welche über die Miniemulsionspolymerisation hergestellt wurden, diente als Templat für die Kristallisation von Calciumphosphat auf den Partikeln. Der Einfluss der funktionellen Carboxylat- und Phosphonat-Oberflächengruppen auf die Komplexierung von Calcium-Ionen sowie die Mineralisation von Calciumphosphat auf der Oberfläche der Nanopartikel wurde mit mehreren Methoden (ionenselektive Elektroden, REM, TEM und XRD) detailliert analysiert. Es wurde herausgefunden, dass die Mineralisation bei verschiedenen pH-Werten zu vollkommen unterschiedlichen Kristallmorphologien (nadel- und plättchenförmige Kristalle) auf der Oberfläche der Partikel führt. Untersuchungen der Mineralisationskinetik zeigten, dass die Morphologie der Hydroxylapatit-Kristalle auf der Partikeloberfläche mit der Änderung der Kristallisationsgeschwindigkeit durch eine sorgfältige Wahl des pH-Wertes gezielt kontrolliert werden kann. Sowohl die Eigenschaften der als Templat verwendeten Polymernanopartikel (z. B. Größe, Form und Funktionalisierung), als auch die Oberflächentopografie der entstandenen Polymer/Calciumphosphat-Hybridpartikel wurden gezielt verändert, um die Eigenschaften der erhaltenen Kompositmaterialien zu steuern. rnEine ähnliche bio-inspirierte Methode wurde zur in situ-Herstellung von organisch/anorganischen Nanokapseln entwickelt. Hierbei wurde die flexible Grenzfläche von flüssigen Miniemulsionströpfchen zur Mineralisation von Calciumphosphat an der Grenzfläche eingesetzt, um Gelatine/Calciumphosphat-Hybridkapseln mit flüssigem Kern herzustellen. Der flüssige Kern der Nanokapseln ermöglicht dabei die Verkapselung unterschiedlicher hydrophiler Substanzen, was in dieser Arbeit durch die erfolgreiche Verkapselung sehr kleiner Hydroxylapatit-Kristalle sowie eines Fluoreszenzfarbstoffes (Rhodamin 6G) demonstriert wurde. Aufgrund der intrinsischen Eigenschaften der Gelatine/Calciumphosphat-Kapseln konnten abhängig vom pH-Wert der Umgebung unterschiedliche Mengen des verkapselten Fluoreszenzfarbstoffes aus den Kapseln freigesetzt werden. Eine mögliche Anwendung der Polymer/Calciumphosphat-Partikel und –Kapseln ist die Implantatbeschichtung, wobei diese als Bindeglied zwischen künstlichem Implantat und natürlichem Knochengewebe dienen. rnIm zweiten Themengebiet dieser Arbeit wurde die Grenzfläche von Nanometer-großen Miniemulsionströpfchen eingesetzt, um einzelne in der dispersen Phase gelöste Polymerketten zu separieren. Nach der Verdampfung des in den Tröpfchen vorhandenen Lösungsmittels wurden stabile Dispersionen sehr kleiner Polymer-Nanopartikel (<10 nm Durchmesser) erhalten, die aus nur wenigen oder einer einzigen Polymerkette bestehen. Die kolloidale Stabilität der Partikel nach der Synthese, gewährleistet durch die Anwesenheit von SDS in der wässrigen Phase der Dispersionen, ist vorteilhaft für die anschließende Charakterisierung der Polymer-Nanopartikel. Die Partikelgröße der Nanopartikel wurde mittels DLS und TEM bestimmt und mit Hilfe der Dichte und des Molekulargewichts der verwendeten Polymere die Anzahl an Polymerketten pro Partikel bestimmt. Wie es für Partikel, die aus nur einer Polymerkette bestehen, erwartet wird, stieg die mittels DLS bestimmte Partikelgröße mit steigendem Molekulargewicht des in der Synthese der Partikel eingesetzten Polymers deutlich an. Die Quantifizierung der Kettenzahl pro Partikel mit Hilfe von Fluoreszenzanisotropie-Messungen ergab, dass Polymer-Einzelkettenpartikel hoher Einheitlichkeit hergestellt wurden. Durch die Verwendung eines Hochdruckhomogenisators zur Herstellung der Einzelkettendispersionen war es möglich, größere Mengen der Einzelkettenpartikel herzustellen, deren Materialeigenschaften zurzeit näher untersucht werden.rn

Untersuchung der Ladung des Neutrons

Die Quantisierung der elektrischen Ladung ist eine der größten Fragestellungen der Physik, die bis heute nicht verstanden ist. Im Standardmodell der Teilchenphysik ist sie beispielsweise nicht mathematisch inhärent erklärbar. Dadurch wäre es möglich, dass das Neutron eine winzige Ladung tragen kann. In dieser Arbeit wurde eine Apparatur auf Grundlage eines Vorgängerexperiments entwickelt, mit der eine Untersuchung der Ladung des Neutrons mit höchster Präzision durchgeführt werden kann. Dabei werden ultrakalte Neutronen in einem optischen System einem elektrischen Feld zwischen zwei Elektrodenplatten ausgesetzt. In der ersten Ladungsmessung mit dieser Apparatur konnte eine statistische Sensitivität von δq≈2,4∙10⁻²⁰ e/√d erreicht werden. Diese Sensitivität ist die höchste, die bisher mit ultrakalten Neutronen für eine Ladungsmessung erreicht werden konnte. In dieser Arbeit wurde das Konzept des Vorgängerexperiments grundlegend überarbeitet, um die Sensitivität der Apparatur zu erhöhen. Es wurden detaillierte Untersuchungen der Systematik der Apparatur durchgeführt und das theoretische Potential der Sensitivität von derzeit δq≈10⁻²¹ e/√d ermittelt. Mit dieser Apparatur wurde der Grundstein für die Messung einer neuen niedrigeren oberen Grenze der elektrischen Ladung des Neutrons gelegt. In nächster Zeit kann dadurch eine niedrigere obere Grenze für die Ladung des Neutrons von q≈10⁻²² e erzielt werden.

Minimally invasive post-mortem CT-angiography in a case involving a gunshot wound

Non-contrast post-mortem computed tomography (pm-CT) is useful in the evaluation of bony pathologies, whereas minimally invasive pm-CT-angiography allows for the detection of subtle vascular lesions. We present a case of an accidentally self-inflicted fatal bullet wound to the chest where pm-CT-angiography revealed a small laceration of the anterior interventricular branch of the left coronary artery and a tiny disruption of the right ventricle with pericardial and pleural effusion. Subsequent autopsy confirmed our radiological findings. Post-mortem CT-angiography has a great potential for the detection of vascular lesions and can be considered equivalent to autopsy for selected cases in forensic medicine.

'Security Here is Not Safe': Violence, Punishment, & Space in the Contemporary U.S. Penitentiary

The US penitentiary at Lewisburg, Pennsylvania, was retrofitted in 2008 to offer the country’s first federal Special Management Unit (SMU) program of its kind. This model SMU is designed for federal inmates from around the country identified as the most intractably troublesome, and features double-celling of inmates in tiny spaces, in 23-hour or 24-hour a day lockdown, requiring them to pass through a two-year program of readjustment. These spatial tactics, and the philosophy of punishment underlying them, contrast with the modern reform ideals upon which the prison was designed and built in 1932. The SMU represents the latest punitive phase in American penology, one that neither simply eliminates men as in the premodern spectacle, nor creates the docile, rehabilitated bodies of the modern panopticon; rather, it is a late-modern structure that produces only fear, terror, violence, and death. This SMU represents the latest of the late-modern prisons, similar to other supermax facilities in the US but offering its own unique system of punishment as well. While the prison exists within the system of American law and jurisprudence, it also manifests features of Agamben’s lawless, camp-like space that emerges during a state of exception, exempt from outside scrutiny with inmate treatment typically beyond the scope of the law.

"Security Here is Not Safe": Violence, Punishment, and Space in the Contemporary US Penitentiary

The US penitentiary at Lewisburg, Pennsylvania, was retrofitted in 2008 to offer the country's first federal Special Management Unit (SMU) program of its kind. This model SMU is designed for federal inmates from around the country identified as the most intractably troublesome, and features double-celling of inmates in tiny spaces, in 23-hour or 24-hour a day lockdown, requiring them to pass through a two-year program of readjustment. These spatial tactics, and the philosophy of punishment underlying them, contrast with the modern reform ideals upon which the prison was designed and built in 1932. The SMU represents the latest punitive phase in American penology, one that neither simply eliminates men as in the premodern spectacle, nor creates the docile, rehabilitated bodies of the modern panopticon; rather, it is a late-modern structure that produces only fear, terror, violence, and death. This SMU represents the latest of the late-modern prisons, similar to other supermax facilities in the US but offering its own unique system of punishment as well. While the prison exists within the system of American law and jurisprudence, it also manifests features of Agamben's lawless, camp-like space that emerges during a state of exception, exempt from outside scrutiny with inmate treatment typically beyond the scope of the law

Exercise training in heart failure: from theory to practice. A consensus document of the Heart Failure Association and the European Association for Cardiovascular Prevention and Rehabilitation

The European Society of Cardiology heart failure guidelines firmly recommend regular physical activity and structured exercise training (ET), but this recommendation is still poorly implemented in daily clinical practice outside specialized centres and in the real world of heart failure clinics. In reality, exercise intolerance can be successfully tackled by applying ET. We need to encourage the mindset that breathlessness may be evidence of signalling between the periphery and central haemodynamic performance and regular physical activity may ultimately bring about favourable changes in myocardial function, symptoms, functional capacity, and increased hospitalization-free life span and probably survival. In this position paper, we provide practical advice for the application of exercise in heart failure and how to overcome traditional barriers, based on the current scientific and clinical knowledge supporting the beneficial effect of this intervention.

Time to initiation of antiretroviral therapy among patients with HIV-associated tuberculosis in Cape Town, South Africa

We studied the time interval between starting tuberculosis treatment and commencing antiretroviral treatment (ART) in HIV-infected patients (n = 1433; median CD4 count 71 cells per microliter, interquartile range: 32-132) attending 3 South African township ART services between 2002 and 2008. The overall median delay was 2.66 months (interquartile range: 1.58-4.17). In adjusted analyses, delays varied between treatment sites but were shorter for patients with lower CD4 counts and those treated in more recent calendar years. During the most recent period (2007-2008), 4.7%, 19.7%, and 51.1% of patients started ART within 2, 4, and 8 weeks of tuberculosis treatment, respectively. Operational barriers must be tackled to permit further acceleration of ART initiation as recommended by 2010 WHO ART guidelines.

Multiple small "imaging" branch-duct type intraductal papillary mucinous neoplasms (IPMNs) in familial pancreatic cancer: indicator for concomitant high grade pancreatic intraepithelial neoplasia?

Most screening programs for familial pancreatic cancer are currently based on endoscopic ultrasonography and/or magnetic resonance imaging (MRI). Cystic lesions, especially those suspicious for small intraductal pancreatic mucinous neoplasms (IPMNs) of the branch ducts, can be visualized in up to 40 % of individuals at risk, but their pathological importance in the setting of FPC is yet not well established. Individuals at risk from a prospective screening program for familial pancreatic cancer with small "imaging" IPMNs of the branch-duct type (BD-IPMN) who underwent pancreatic resection were analysed regarding clinico-pathological data and the locations of pancreatic lesions. Five of 125 individuals at risk who underwent screening had multiple small (size 2-10 mm) unicystic lesions and/or multicystic single lesions in the pancreatic body and tail suspicious for BD-IPMNs upon MRI imaging and decided to undergo surgical resection after interdisciplinary counselling, although none fulfilled the consensus criteria for IPMN resection. Histological examination revealed BD-IPMNs with low or moderate dysplasia of the gastric type in combination with multifocal PanIN2 and PanIN3 lesions in 4 individuals. The remaining patient had only tiny ductectasias in the pancreatic tail with multifocal PanIN 2 lesions in the entire gland and one PanIN3 lesion in the pancreatic head. Intriguingly, the location of the most dysplastic histological lesions (PanIN3) did not correspond to the preoperatively detected lesions and were not visible in preoperative imaging. In the setting of FPC, the presence of multiple small "imaging" BD-IPMNs may indicate the presence of high-grade PanIN lesions elsewhere in the pancreas.

Transnational Marriage: Modern Imaginings, Relational Realignments, and Persistent Inequalities

In the context of shifting cultural anchors as well as unstable global economic conditions, new practices of intimacy and sexuality may become tactics in an individual’s negotiation of conflicting desires and potentials. This article offers reflection on the interface between global forces, powerful transcultural narratives, and state policies, on the one hand, and local, even individual, constructions and tactics in regard to sexuality, marriage, migration, and work, on the other. The article focuses on the life trajectory of Gudiya, an ambitious young Hindu woman who started out life with little social capital and few economic resources in a dusty corner of what was then the tiny kingdom of Nepal. Gudiya’s story highlights the ways in which she has engaged in relational realignments aimed at bringing her closer to the life she imagines, even as she has encountered new and persistent forms of inequality both local and transnational in scale.

Homeland security: IgA immunity at the frontiers of the body

IgA is the most abundant immunoglobulin produced in mammals, and is mostly secreted across mucous membranes. At these frontiers, which are constantly assaulted by pathogenic and commensal microbes, IgA provides part of a layered system of immune protection. In this review, we describe how IgA induction occurs through both T-dependent and T-independent mechanisms, and how IgA is generated against the prodigious load of commensal microbes after mucosal dendritic cells (DCs) have sampled a tiny fraction of the microbial consortia in the intestinal lumen. To function in this hostile environment, IgA must be induced behind the 'firewall' of the mesenteric lymph nodes to generate responses that integrate microbial stimuli, rather than the classical prime-boost effects characteristic of systemic immunity.

Hydrologic analysis of a limestone quarry using EPA's HELP Version 3.08 Model

Aggregates were historically a low cost commodity but with communities and governmental agencies reducing the amount of mining the cost is increasing dramatically. An awareness needs to be brought to communities that aggregate production is necessary for ensuring the existing infrastructure in today’s world. This can be accomplished using proven technologies in other areas and applying them to show how viable reclamation is feasible. A proposed mine reclamation, Douglas Township quarry (DTQ), in Dakota Township, MN was evaluated using Visual Hydrologic Evaluation of Landfill Performance (HELP) model. The HELP is commonly employed for estimating the water budget of a landfill, however, it was applied to determine the water budget of the DTQ following mining. Using an environmental impact statement as the case study, modeling predictions indicated the DTQ will adequately drain the water being put into the system. The height of the groundwater table will rise slightly due to the mining excavations but no ponding will occur. The application of HELP model determined the water budget of the DTQ and can be used as a viable option for mining companies to demonstrate how land can be reclaimed following mining operations.

Analysis of spring break-up and its effects on a biomass feedstock supply chain in northern Michigan

Demand for bio-fuels is expected to increase, due to rising prices of fossil fuels and concerns over greenhouse gas emissions and energy security. The overall cost of biomass energy generation is primarily related to biomass harvesting activity, transportation, and storage. With a commercial-scale cellulosic ethanol processing facility in Kinross Township of Chippewa County, Michigan about to be built, models including a simulation model and an optimization model have been developed to provide decision support for the facility. Both models track cost, emissions and energy consumption. While the optimization model provides guidance for a long-term strategic plan, the simulation model aims to present detailed output for specified operational scenarios over an annual period. Most importantly, the simulation model considers the uncertainty of spring break-up timing, i.e., seasonal road restrictions. Spring break-up timing is important because it will impact the feasibility of harvesting activity and the time duration of transportation restrictions, which significantly changes the availability of feedstock for the processing facility. This thesis focuses on the statistical model of spring break-up used in the simulation model. Spring break-up timing depends on various factors, including temperature, road conditions and soil type, as well as individual decision making processes at the county level. The spring break-up model, based on the historical spring break-up data from 27 counties over the period of 2002-2010, starts by specifying the probability distribution of a particular county’s spring break-up start day and end day, and then relates the spring break-up timing of the other counties in the harvesting zone to the first county. In order to estimate the dependence relationship between counties, regression analyses, including standard linear regression and reduced major axis regression, are conducted. Using realizations (scenarios) of spring break-up generated by the statistical spring breakup model, the simulation model is able to probabilistically evaluate different harvesting and transportation plans to help the bio-fuel facility select the most effective strategy. For early spring break-up, which usually indicates a longer than average break-up period, more log storage is required, total cost increases, and the probability of plant closure increases. The risk of plant closure may be partially offset through increased use of rail transportation, which is not subject to spring break-up restrictions. However, rail availability and rail yard storage may then become limiting factors in the supply chain. Rail use will impact total cost, energy consumption, system-wide CO2 emissions, and the reliability of providing feedstock to the bio-fuel processing facility.

Simulating dioxane transport in a heterogeneous glacial aquifer system (Washtenaw County, Michigan) using publicly available models and data

The primary challenge in groundwater and contaminant transport modeling is obtaining the data needed for constructing, calibrating and testing the models. Large amounts of data are necessary for describing the hydrostratigraphy in areas with complex geology. Increasingly states are making spatial data available that can be used for input to groundwater flow models. The appropriateness of this data for large-scale flow systems has not been tested. This study focuses on modeling a plume of 1,4-dioxane in a heterogeneous aquifer system in Scio Township, Washtenaw County, Michigan. The analysis consisted of: (1) characterization of hydrogeology of the area and construction of a conceptual model based on publicly available spatial data, (2) development and calibration of a regional flow model for the site, (3) conversion of the regional model to a more highly resolved local model, (4) simulation of the dioxane plume, and (5) evaluation of the model's ability to simulate field data and estimation of the possible dioxane sources and subsequent migration until maximum concentrations are at or below the Michigan Department of Environmental Quality's residential cleanup standard for groundwater (85 ppb). MODFLOW-2000 and MT3D programs were utilized to simulate the groundwater flow and the development and movement of the 1, 4-dioxane plume, respectively. MODFLOW simulates transient groundwater flow in a quasi-3-dimensional sense, subject to a variety of boundary conditions that can simulate recharge, pumping, and surface-/groundwater interactions. MT3D simulates solute advection with groundwater flow (using the flow solution from MODFLOW), dispersion, source/sink mixing, and chemical reaction of contaminants. This modeling approach was successful at simulating the groundwater flows by calibrating recharge and hydraulic conductivities. The plume transport was adequately simulated using literature dispersivity and sorption coefficients, although the plume geometries were not well constrained.

"Brethren upon the same level" : membership and class in Calumet's Masonic Lodge

The Keweenaw Peninsula of Upper Michigan was a ethnic conglomerate of cultures and ideas, with people attracted to the area by the mineral wealth found along the Copper Range. The center of copper mining from the mid 1860s to 1968 was in the vicinity of Calumet Township, home to the world-famous Calumet and Hecla Mining Company. The township depended on the mines and the company’s president Agassiz’s strove to make the area a “model community,” that included groups such as the Free and Accepted Masons. Men from myriad backgrounds arrived in Calumet from the British Isles, Germany, Finland, Eastern and Southern Europe and the Eastern United States. As in other communities from the time period these men formed common interest groups like Masonic Lodge 271, which received its charter in 1870. Gentlemen joined with merchants and craftsmen. They became “brethren upon the same level,” and were elevated to the status of Master Mason. This symbolic transformation within the Lodge removed the men from the “profane world” outside the sanctity of Masonry, and in the ritualistic transformation of the meeting they were reborn into Masonry’s sacred mysteries. Masonry acted as a means of moral guidance to men and gave them access to a larger social and economic community through a common connection of brotherhood. As the candidates moved through the three Blue Lodge degrees of Entered Apprentice, Fellowcraft, and Master Mason they saw each other as “brethren upon the same level” – all economic classes equal within the Masonic Lodge. To examine equality within Lodge 271, this study sorted workers into classes to allow a comparison of Lodge 271’s membership. Possibly a comparison between other lodges can be drawn from the membership. The Union Building in Calumet, MI will be examined for its role in the ritualistic transformation of Masonry as it housed Masonic activities and transformations. This transformation brought men into the lodge of brothers. While Masonry professed equality between members however, to what extent did the membership of the lodge reflect this between the brethren? To what extent did economic class determine who was made “brethren upon the same level? 1 Arthur Thurner, Calumet Copper and People: History of a Michigan Mining Community, 1864-1970 (Hancock, MI: Book Concern, 1974), 122.