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Medical Interventions for Non-Disease States. A conceptual, epistemic and ethical analysis on hormonal contraceptives
Full text linkThis dissertation is a philosophical analysis of the medical treatment and research of non-disease states and the conceptual, ethical, and epistemological challenges involved. I use a case study approach and focus in particular on the prescription and biomedical research of hormonal contraceptives. The dissertation consists of an introduction (Chapter 1), three articles (Chapters 2, 3, 4), and a conclusion (Chapter 5). The central aim is to show that while we have good reasons to apply medicine pragmatically to non-disease conditions, we should be very sensitive to the goals we have in applying medicine to specific non-disease conditions, whether they are being met, and whether they conflict with the goals embedded in medical practice and research traditions. We should not simply apply medicine as if we were treating disease conditions. This enables oppression in the form of sexism and paternalism, and does neither ethical nor epistemic justice to the social role of medicine in society. As philosophers, we are therefore obliged to carefully analyze the nature and rules of pragmatic medicine as we find it in the world, beyond conditions that we can clearly identify as diseases.
Chapter 1 is an introduction to the main topics of the dissertation and its structure. In Chapter 2, I discuss how our framing of the benefits, risks, and side effects of hormonal contraception is shaped by structurally embedded assumptions about the responsibilities and goals of medicine. The fundamental problem identified in this chapter is that, while pragmatic approaches to medicine are accepted and should be accepted, in the face of potential harms, medical professionals prioritize disease prevention over the prevention of other harms. This allows for a sexist double standard in weighing the harms of pregnancy and contraception. In Chapter 3 I examine how the structurally embedded assumptions on medical goals and the priorities create flawed epistemic standards and inappropriate epistemic risk balancing. I argue that the standard required and used for the research and communication of minor adverse events in clinical guidelines is unproductive and primarily supports negative results. This is not only an inadequate balance between the different dimensions of the search for truth, but it also disrespects the epistemic interests of patients by prioritizing public health concerns over their autonomous decisions. In Chapter 4, I further analyze the oppressive potential of pragmatic medicine that also treats non-disease states. I argue that the oppressive impact of medicalization largely arises from a mismatch between our expectations of medicine as a social institution—expectations that grant it authority—and the actual communicative and scientific practices within medicine. While these practices often signal alignment with our expectations, they frequently fall short of fulfilling them. Chapter 5 concludes the dissertation
Gravitational curvature and relativistic effects in atom interferometers
Full text linkDiese Arbeit widmet sich der theoretischen Untersuchung von Atominterferometern in komplexen Gravitationsfeldern. Die zugrunde gelegten Gravitationsmodelle umfassen einerseits nicht-triviale Korrekturen im Gravitationspotenzial im Rahmen der klassischen Newtonschen Mechanik, die über die Annahme eines idealisierten oder vollständig homogenen Gravitationsfeldes hinausgehen. Andererseits wird die allgemeine Relativitätstheorie herangezogen, um insbesondere im Bereich schwacher Gravitationsfelder eine post-newtonsche Beschreibung zu ermöglichen. Diese Herangehensweise erlaubt es, die dominanten Auswirkungen einer Raumzeitkrümmung systematisch zu erforschen. Die in dieser Arbeit behandelten quantenoptischen Systeme sind Atominterferometer, Experimente, die kalte Atome bzw. Bose-Einstein-Kondensate zur Interferenz bringen. Diese Beschreibung bietet einen möglichen Ansatz, um die Grenzen der modernen Physik auszutesten, und erkundet Regionen, in denen Effekte der Quantengravitation zum Vorschein kommen könnten, die sich von denen der Hochenergiephysik unterscheiden.
Wir beginnen mit einer Einführung in die (allgemeine) Relativitätstheorie und die Theorie der Atominterferometer in idealisierten, Newton’schen Gravitationsfeldern. Um das Gravitationsmodell schrittweise zu erweitern und zusätzliche Effekte wie die Raumzeitkrümmung zu integrieren, führen wir eine kompaktere Notation ein. Diese ermöglicht es uns, die Komplexität durch relativistische Effekte systematisch zu berücksichtigen. In dieser neuen Notation präsentieren wir den aktuellen Forschungsstand auf diesem Gebiet, sodass wir direkt darauf aufbauen und die neuesten Entwicklungen integrieren können. Des Weiteren stellen wir eine neue Interferometergeometrie vor, die besonders gut zur Detektion gravitativer Krümmungen
geeignet ist. Wir führen eine detaillierte Analyse durch, um zu untersuchen, wie sich ein solches Interferometer in idealisierten Gravitationsfeldern verhält, und vergleichen dies mit einer numerischen Simulation desselben Interferometers im VLBAI Hannover, welches das neueste und größte Atominterferometer-Experiment in Hannover darstellt. Wir nutzen dieses Beispiel, da uns in diesem Experiment ein präzises Modell des Gravitationsfeldes zur
Verfügung steht.
Die durch nicht-triviale Gravitationsfelder und die Relativitätstheorie verursachten Korrekturen treten an vielen Stellen in der theoretischen Beschreibung auf. Dies führt dazu, dass die Endergebnisse, insbesondere bei komplexen Interferometergeometrien, schnell unübersichtlich werden. Um das Risiko zu verringern, Terme und Effekte zu übersehen, war es ein wesentlicher Teil dieser Arbeit, einen Computer-Algorithmus zu entwickeln, der die Berechnung dieser Terme automatisiert. Dadurch können wir in kurzer Zeit zuverlässig Ergebnisse auch für sehr komplexe Experimente modellieren. Die Kombination aus einem Computer-Algorithmus, der uns algebraische Resultate liefert, und einem numerischen Modell für ein explizit gemessenes Gravitationsfeld ermöglicht es uns, Theorie und Experiment besonders detailliert zu vergleichen. Darüber hinaus können wir neue Resultate für zukünftige Experimente im VLBAI Hannover und in anderen Atominterferometern weltweit ableiten.This work is a theoretical investigation of atom interferometers in complex gravitational fields. The underlying gravitational models include non-trivial corrections in the gravitational potential within the framework of classical Newtonian mechanics, which go beyond the assumption of an idealised or even completely homogeneous gravitational field. On the other hand, the theory of general relativity is used to enable a post-Newtonian description, particularly in the area of weak gravitational fields. This approach makes it possible to systematically investigate the main effects of spacetime curvature. The quantum optical systems discussed in this work are atom interferometers, highly accurate experiments that cause cold atoms or Bose-Einstein condensates to interfere. This description offers a potential approach to testing the boundaries of modern physics and explores regions where quantum gravity may emerge, distinct from the realm of high-energy physics.
We start with an introduction to the theory of (general) relativity and the theory of atomic interferometers in idealised Newtonian gravitational fields. In order to gradually extend the gravitational model and integrate additional effects such as spacetime curvature, we introduce a more compact and versatile notation. This allows us to systematically take into account the additional complexity due to relativistic effects. With this new notation, we present the current state of research in this field, enabling us to directly build upon it and seamlessly incorporate our own developments. Furthermore, we present a new interferometer geometry that is particularly well suited for the detection of gravitational curvature. We perform a
detailed analysis to investigate how such an interferometer behaves in idealised gravitational fields and compare this with a numerical simulation of the same interferometer at the VLBAI facility in Hannover, which is the newest large scale atom interferometer experiment in Hannover. We use this example because this experiment provides us with a precise model of the gravitational field.
The corrections caused by non-trivial gravitational fields and the theory of relativity occur at many levels in the theoretical description. This means that the final results quickly become unwieldy, especially in the case of more complex interferometer geometries. To reduce the risk of overlooking terms and effects, an essential part of this work was to develop a computer algorithm that automates the calculation of this algebra. This enables us to reliably model results even for very complex experiments in a short time. The combination of a computer algorithm that provides us with algebraic results and a numerical model for an explicitly measured gravitational field enables us to compare theory and experiment in great detail. In addition, we can derive new results for future experiments in the VLBAI Hannover and in other atom interferometers worldwide
Interview mit Milena Michiko Flašar im Rahmen von LiteraTour Nord 2024
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Pathways to competitiveness in high-tech industries: technological shifts, standardization, and regional innovation
Full text linkInnovation lies at the core of technological progress, driving transformative changes in industries and fundamentally reshaping economic structures and regions. At the same time, the increasing global reach of technology and the growing interdependence of systems have elevated the importance of international technology standards. Those regions and firms that can effectively shape technological trajectories and standards are positioned to emerge as leading actors, defining the direction of innovation and capturing value in critical industries.
This cumulative dissertation examines these multidimensional dynamics shaping technological trajectories and economic development, focusing on country-specific differences in embeddedness and influence in global standards development, and on the role of regional capabilities in the innovation and adoption of emerging technologies. Looking at two different high-tech industries — the telecommunications and automotive sector — this dissertation sheds light on how firms and regions navigate and influence these processes. Utilizing quantitative data analysis, the research draws on technical contributions from within an international standardization body, patent records, and online job advertisement data.
The findings reveal that actors from the Global South, namely China, face multifaceted hurdles in international ICT standards development, highlighting disparities in the ability to influence standardization outcomes — the so-called standardization gap. However, the research also shows that strategic collaborations and generational technology shifts may offer leverage to increase their embeddedness and influence on their path to becoming global standard-setters.
Examining how such technological shifts and path developments unfold at the regional level, the dissertation further analyzes how regional technological capabilities affect the innovation and adoption of automated driving technologies in Germany. The emergence of these technologies poses significant disruptions, and challenges established automotive regions rooted in mechanical engineering to integrate advanced digital competencies. The research shows that conventional automotive regions lacking complementary ICT capabilities may struggle to fully adapt to this disruption, facing difficulties in achieving successful path renewal.
These results carry various policy recommendations and provide impulses for future research — in economic geography and beyond
Interactions of manganese oxides with natural dissolved organic matter
Full text linkThe long-term storage and stabilization of organic carbon (OC) in soils is largely governed by secondary aluminosilicates and metal (oxyhydr)oxides, which play a pivotal role in reducing the bioavailability of organic matter (OM) through sorption processes. Manganese (Mn) oxides, which are ubiquitous and highly redox-active, also interact strongly with dissolved organic matter (DOM). The properties of both Mn oxides and DOM are substantially altered by reductive dissolution and phase transformation of the Mn oxides and by sorption, sorptive fractionation, oxidation, and polymerization of the DOM. This, in turn, affects the reactivity of the Mn oxides as well as the bioavailability and chemical properties of the DOM, thereby considerably influencing the OC dynamics in soils. There is still a lack of studies encompassing different types of soil-relevant Mn oxides and natural soil DOM types under varying solution conditions. This work addresses this gap by providing two comprehensive studies that gain deeper insights into the Mn oxide-DOM interactions by using various soil-relevant Mn oxides and DOM types under changing solution conditions.
The first study comprises insights from sorption experiments on the interaction of δ-MnO2, acid birnessite, and cryptomelane with beech and pine DOM at pH 4 and 7 in changing background electrolytes (BGE; no-salt, NaCl, and CaCl2). The processes of DOM sorption, sorptive fractionation, and oxidation in relation to Mn oxide properties, DOM type, pH and BGE were assessed and evaluated. While the OC sorption was enhanced under acidic conditions and for more aromatic DOM, the DOM was also effectively oxidized to CO2 and low-molecular-weight organic acids (LMWOA), resulting more in a destabilization of soil OC.
The second study investigates changes in Mn oxides and DOM at the molecular level. There-fore, changes in Mn oxidation states and sorbed carbon (C) species on the surfaces of reacted Mn oxides were assessed by X-ray photoelectron spectroscopy (XPS). Changes in molecular characteristics of reacted DOM were examined by liquid chromatography coupled to Fourier-transform ion cyclotron resonance mass spectroscopy (LC-FT-ICR-MS). Most surfaces of reacted Mn oxides were significantly reduced by DOM and sorbed C shifted more to oxidized C species. In general, DOM sorption prevailed initially, followed by oxidation and polymerization reactions with increasing reaction time. Discrete sub-pools were identified in the DOM that differ clearly in their reactivity with Mn oxides and underlines the complexity of natural DOM.
The results of both studies contribute substantially to a better understanding of the Mn oxide-DOM interaction and emphasize the importance of Mn oxides in soil OC dynamics and their potential to determine the fate and bioavailability of DOM as well as of associated nutrients and contaminants
A Review of In-Space Manufacturing Induced Surface Integrity
Full text linkThe surface integrity of any material plays a vital role in the service life of the exposed surface, which significantly affects the interaction with the environment, response to the chemical effect over the surface, response towards the corrosion, and interaction with the other material. Materials exposed to outer space are subjected to harsh environments such as charged particle radiation, temperature effects, thermal cycling, impacts from the micrometeoroids and debris and photon radiation, etc., that lead to deformation, erosion, corrosion, cracks, and microstructural degeneration. Fundamentally, surface integrity is one of the most essential properties of the surfaces exposed to the outer space environment. The component's operation quality, reliability, and surface life depend on the surface integrity. Due to the above-mentioned harsh environment and unique challenges, the surfaces are often repaired using repair techniques such as human-robotic intervention, and advanced material techniques involve the changes in the parent surface. Since space missions depend on the functionality of the repaired parts, hence it becomes essential to analyze the surface obtained after performing the repairs in the outer space environment. This work focuses on the review of the repaired surface's surface integrity metrics in in-space environments. The reviewed surface integrity metrics include surface roughness, microstructure, residual stresses, and microhardness. Since, in the outer space environment, working is different from the Earth as resources are deficient. Hence, searching for a sustainable solution is the key to performing repair and obtaining desired surface integrity without compromising the performance. Therefore, the sustainability aspects of the repair techniques and the obtained surface integrity are discussed in the present study. The paper concludes that the surface integrity of in-space manufactured parts is seldom studied or prioritized as the primary research concept under investigation. With the increasing impetus for space exploration, this concept needs immediate attention
Promotion of functional biodiversity to control the cabbage whitefly Aleyrodes proletella
Full text linkIn recent decades, the cabbage whitefly Aleyrodes proletella has evolved into a major pest in both organic and integrated cabbage production. This was partly attributed to the one-sided advantage gained from the increased cultivation of winter oilseed rape, which favours A. proletella but not its natural enemies. As part of a joint project, this thesis’ aim was to boost these natural enemies, specifically employing banker plant systems and tailored flower strips, with the goal of decreasing A. proletella infestation, reducing economic damage, and minimizing insecticide applications.
The approach began with identifying the most relevant natural enemies of A. proletella in Germany through a nationwide survey (chapter 1). Subsequently, potential banker plant systems were developed under controlled conditions, followed by the evaluation of the most promising annual banker plant systems in field experiments (chapter 2). Chapter 3 and chapter 4 further investigated the overwintering, and population dynamics of alternative hosts/prey and natural enemies on perennial banker plants, respectively. Eventually, a field trial assessed the suitability of selected flowering plant species for a tailored flower strip in cabbage crops (chapter 5).
Encarsia tricolor, recognized as the most crucial parasitoid of A. proletella, was selected as the natural enemy in the banker plant systems. The annual banker plant system with the highest impact on A. proletella consisted of E. tricolor (natural enemy) and Trialeurodes vaporariorum (alternative host/prey) on Hokkaido squash. This system resulted in an average of 28% reduction in A. proletella populations over short distances in the field. Parasitism rates of A. proletella increased by 52% on average, and there were higher abundances of hoverfly larvae and ladybeetles on cabbage plants. On a perennial banker plant system, alternative hosts/prey (Aleyrodes lonicerae) and natural enemies successfully overwintered on and colonized wood avens (Geum urbanum) permanently.
The results demonstrate that the implementation of banker plant systems can effectively pro-mote functional biodiversity and lead to a significant reduction in A. proletella infestation. However, further improvements in the developed banker plant systems are discussed and re-search gaps are identified that will need to be addressed in future studies before practical implementation.In den letzten Jahrzehnten hat sich die Kohlmottenschildlaus Aleyrodes proletella zu einem bedeutenden Schädling sowohl im ökologischen als auch im integrierten Kohlanbau entwickelt. Dies wurde teilweise auf den vermehrten Anbau von Winterraps zurückgeführt, der zwar A. proletella begünstigt, jedoch nicht seine natürlichen Gegenspieler. Im Rahmen eines Verbundprojektes sollte daher im vorliegenden Teilprojekt die funktionelle Biodiversität gefördert werden. Das Ziel war es, den Befall von A. proletella zu verringern, wirtschaftliche Schäden zu reduzieren und den Einsatz von Insektiziden zu minimieren.
Die Untersuchungen begannen mit der Identifizierung der relevantesten natürlichen Gegenspieler von A. proletella in Deutschland durch ein bundesweites Monitoring (Kapitel 1). Anschließend wurden potenzielle Offene Zucht-Systeme unter kontrollierten Bedingungen entwickelt und die vielversprechendsten einjährigen Systeme in Feldversuchen evaluiert (Kapitel 2). Zudem wurde die Überwinterungsbiologie (Kapitel 3) und die Populationsdynamik von Alternativwirten/-beute und natürlichen Gegenspielern an mehrjährigen Offene Zucht-Systemen untersucht (Kapitel 4). Schließlich wurde in einem Feldversuch die Eignung ausgewählter Blütenpflanzen für einen maßgeschneiderten Blühstreifen im Kohlanbau bewertet (Kapitel 5).
Encarsia tricolor, der bedeutendste Parasitoid von A. proletella, wurde als natürlicher Gegenspieler für die Offene Zucht-Systeme ausgewählt. Das vielversprechendste einjährige Offene Zucht-System bestand aus E. tricolor (natürlicher Gegenspieler) und Trialeurodes vaporariorum (Alternativwirt/-beute) auf Hokkaido-Kürbis. Dieses System führte in Feldversuchen auf kurzer Distanz zum Kohl zu einer durchschnittlichen A. proletella-Reduktion um 28%. Die Parasitierungsrate von A. proletella stieg im Durchschnitt um 52%, und es befand sich eine größere Anzahl an Schwebfliegenlarven und Marienkäfern an den Kohlpflanzen. In einem mehrjährigen Offene Zucht-System überwinterten Alternativwirte/-beute und natürliche Gegenspieler erfolgreich und besiedelten dauerhaft den Echten Nelkenwurz (Geum urbanum).
Die Ergebnisse zeigen, dass die Implementierung von Offene Zucht-Systemen zu einer Förderung der funktionalen Biodiversität und zu einer signifikanten Reduktion des Befalls durch A. proletella führen kann. Weitere Optimierungsmöglichkeiten der entwickelten Offene Zucht-Systeme sowie Wissenslücken, die in zukünftigen Studien vor der praktischen Umsetzung geschlossen werden sollten, werden diskutiert
Backpackers across the Salt Flat: tourism-related social and cultural conflicts in Salar de Uyuni, Bolivia
Full text linkSalar de Uyuni, in Bolivia, has become a beloved destination for backpackers. They first arrived in the 90s as a handful of adventurers and, throughout the decades, became a constant flow of tourists who wished to see the beauties of the Andean Altiplano and the most extensive salt flat in the world. The Salar is located West of Uyuni, a city in the Potosí department that became the tourism capital of Bolivia. There, inbound tourism has grown exponentially, changing the landscape, putting hosts and visitors in contact, and transforming the economy in the region. In 2016 the city received almost 300.000 foreign tourists, representing 10 times its population.
On the one hand, backpackers from many countries look for the cheapest tours and hotels and soon depart for their next adventure. On the other hand, there is an indigenous host community, tourism workers and entrepreneurs, and government officials. Considering the dynamic between the aforementioned social actors, this study aims to understand how the massive growth of tourism in Salar de Uyuni and the southern Altiplano is causing social and cultural conflicts in the region and what these conflicts are. The goal is to contribute to theories of cultural and social conflict management and tourism development in indigenous regions and potentially inform future policy objectives for other Latin American countries with similar
settings.
When seeing conflicts as symptoms of social inequalities and power struggles, it is possible to analyse the consequences of the backpacking boom in Uyuni and surrounding Altiplano, a remote and highly impoverished region populated by indigenous peoples, where resources like potable water and fertile land are scarce. The literature used to support this analysis was the social conflict theory from Simmel’s Streit (1955), the concept of cultural conflicts in tourism from Robinson (1999), the encounter culture from Santana (2009) and the backpacking tourism theory (Cohen, 2004; Richards & Wilson, 2004; Hannam & Ateljevic, 2008).
Qualitative methods were used to understand and categorise social and cultural conflicts, and multi-sited field research was conducted to provide the necessary data. The investigation in the field was based on observant participation and in-depth interviews with members of three of the four social groups involved in tourism in Uyuni, them being: a) backpackers (visitors), b) representatives of the government, and c) the tourism industry. Unfortunately, no members of the d) native population (hosts) could not be interviewed due to difficulties in the field. The interviews were then analysed through a line-by-line examination using the software MAXQDA, which generated 168 codes divided into five groups and revealing a pattern in the data. As secondary sources, photographs, brochures, travel guides, newspapers, travelogues, and peer-reviewed articles on related themes were used.
The results show that the conflicts around the Salar de Uyuni tour can be divided into the groups man vs. nature, backpackers’ behaviour, industry standards, tourism policy and local culture. For each of the four social actors, conflicts mainly occur because 1) hosts are excluded from the tourism industry, except when in the character of servants; 2) the industry is a liberal tourism market based on informality; 4) guests have service-related conflicts; and 6) government attempts to regulate and professionalise of the tourism system.
Despite looking seemingly different from each other, the four themes have a common axis: the unplanned character of the local tourism industry, which was developed spontaneously by outsiders. The government’s incapacity to regulate the services offered and its role as a mediator of conflicts over land and natural resources is also a reason for the identified struggles.
Further research is recommended, as it is necessary to investigate deeper how tourism promotes cultural change in the area's smaller and more traditional communities. It is also essential to do comparative studies with other indigenous regions of the world that receive masses of tourists to understand how to integrate the local communities into the tourism process without forcing them into conforming to a western organisation of time, space, and services.Der Salar de Uyuni in Bolivien ist zu einem beliebten Ziel für Rucksacktouristen
geworden. Sie kamen erstmals in den 90er Jahren als eine Handvoll Abenteurer und wurden im Laufe der Jahrzehnte zu einem konstanten Strom von Touristen, die die Schönheiten des Anden-Altiplano und den größten Salzsee der Welt sehen wollten. Der Salar liegt westlich von Uyuni, einer Stadt im Departement Potosí, die zur Tourismushauptstadt Boliviens wurde. Dort ist der Einreiseverkehr exponentiell gewachsen, hat die Landschaft verändert, Gastgeber und Besucher in Kontakt gebracht und die Wirtschaft in der Region verändert. Im Jahr 2016 empfing die Stadt fast 300.000 ausländische Touristen, was dem Zehnfachen ihrer Einwohnerzahl entspricht. Auf der einen Seite suchen Rucksacktouristen aus vielen Ländern nach den günstigsten Touren und Hotels und brechen bald zu ihrem nächsten Abenteuer auf. Auf der anderen Seite
gibt es eine einheimische Gastgemeinde, Tourismusarbeiter und -unternehmer sowie Regierungsbeamte. In Anbetracht der Dynamik zwischen den oben genannten sozialen Akteuren will diese Studie verstehen, wie das massive Wachstum des Tourismus in Salar de Uyuni und dem südlichen Altiplano soziale und kulturelle Konflikte in der Region verursacht und worin diese Konflikte bestehen. Das Ziel ist es, einen Beitrag zu den Theorien der kulturellen und sozialen Konfliktbewältigung und der Tourismusentwicklung in indigenen Regionen zu leisten und möglicherweise zukünftige politische Ziele für andere lateinamerikanische Länder mit ähnlichen Rahmenbedingungen zu formulieren Wenn man Konflikte als Symptome sozialer Ungleichheiten und Machtkämpfe betrachtet, ist es möglich, die Folgen des Rucksacktourismusbooms in Uyuni und dem umliegenden Altiplano zu analysieren, einer abgelegenen und stark verarmten Region, die von indigenen Völkern bewohnt wird und in der Ressourcen wie Trinkwasser und fruchtbares Land knapp sind. Als Literatur zur Unterstützung dieser Analyse wurden die soziale Konflikttheorie von Simmels Streit (1955), das Konzept der kulturellen Konflikte im Tourismus von Robinson
(1999), die Begegnungskultur von Santana (2009) und die Theorie des Rucksacktourismus (Cohen, 2004; Richards & Wilson, 2004; Hannam & Ateljevic, 2008) verwendet. Qualitative Methoden wurden eingesetzt, um soziale und kulturelle Konflikte zu verstehen und zu kategorisieren, und es wurde eine Feldforschung mit mehreren Standorten durchgeführt, um die erforderlichen Daten zu erhalten. Die Untersuchung vor Ort basierte auf beobachtender Teilnahme und ausführlichen Interviews mit Mitgliedern von drei der vier sozialen Gruppen, die am Tourismus in Uyuni beteiligt sind: a) Rucksacktouristen (Besucher), b) Vertreter der Regierung und c) der Tourismusindustrie. Leider konnten aufgrund von Schwierigkeiten vor Ort keine Mitglieder der d) einheimischen Bevölkerung (Gastgeber) befragt werden. Die Interviews wurden anschließend zeilenweise mit Hilfe der Software MAXQDA analysiert, die 168 Codes generierte, die in fünf Gruppen unterteilt waren und ein Muster in den
Daten erkennen ließen. Als Sekundärquellen wurden Fotos, Broschüren, Reiseführer, Zeitungen, Reiseberichte und Fachartikel zu verwandten Themen herangezogen. Die Ergebnisse zeigen, dass sich die Konflikte rund um die Salar de Uyuni-Tour in die Gruppen Mensch gegen Natur, Verhalten von Rucksacktouristen, Industriestandards, Tourismuspolitik und lokale Kultur unterteilen lassen. Für jeden der vier sozialen Akteure entstehen Konflikte hauptsächlich dadurch, dass 1) die Gastgeber von der Tourismusindustrie
ausgeschlossen sind, es sei denn, sie haben den Charakter von Bediensteten; 2) die Industrie ein liberaler Tourismusmarkt ist, der auf Informalität basiert; 4) die Gäste servicebezogene Konflikte haben; und 6) die Regierung versucht, das Tourismussystem zu regulieren und zu professionalisieren. Obwohl die vier Themen auf den ersten Blick unterschiedlich erscheinen, haben sie eine gemeinsame Achse: den ungeplanten Charakter der lokalen Tourismusindustrie, die spontan von Außenstehenden entwickelt wurde. Die Unfähigkeit der Regierung, die angebotenen Dienstleistungen zu regulieren und ihre Rolle als Vermittler bei Konflikten um Land und natürliche Ressourcen ist ebenfalls ein Grund für die festgestellten Kämpfe. Weitere Forschungsarbeiten werden empfohlen, da genauer untersucht werden muss, wie der Tourismus den kulturellen Wandel in den kleineren und traditionelleren Gemeinden des Gebiets fördert. Es ist auch wichtig, vergleichende Studien mit anderen indigenen Regionen der Welt durchzuführen, die Massen von Touristen empfangen, um zu verstehen, wie die lokalen Gemeinschaften in den Tourismusprozess integriert werden können, ohne sie zu zwingen, sich
einer westlichen Organisation von Zeit, Raum und Dienstleistungen anzupassen
Development of postharvest disinfestation treatment protocols against major quarantine pests of export fruits and vegetables
Full text linkIn sub-Saharan Africa, mango (Mangifera indica L.), French beans (Phaseolus vulgaris L.), and bell pepper (Capsicum annuum L.) are three economically significant horticultural crops. Despite their economic and nutritional significance, their production and trade are hampered by several constraints; chief among them is infestation by devastating quarantine pests such as oriental fruit fly (Bactrocera dorsalis), western flower thrips (Frankliniella occidentalis) and false codling moth (Thaumatotibia leucotreta). Preharvest control measures have been developed and implemented against these pests, however, being considered as A1 and A2 pests in many importing countries, postharvest measures are required to guarantee quarantine security in these countries. In this regard, this study aimed to (1) Develop postharvest hot water treatment (HWT) protocols for Tommy Atkins mango, French beans, and bell pepper against B. dorsalis, F. occidentalis, and T. leucotreta, respectively, (2) Assess the effect of the HWT regimes on the quality of the treated commodities and (3) Elucidate the differential gene expression of T. leucotreta under extreme temperature treatments. The results of HWT for postharvest disinfestation of Tommy Atkins mango against B. dorsalis show that the third larval instar is the most heat tolerant stage of B. dorsalis, and the minimum time required to achieve its probit-9 control efficacy (99.9968% mortality), at 46.1ºC is 72.63 min. The findings of HWT for postharvest disinfestation of French beans against F. occidentalis egg indicate that 8.01 min is the minimum immersion time required to achieve probit-9 control efficacy at 45ºC. In the assessment of the effectiveness of HWT as a phytosanitary treatment for T. leucotreta in bell pepper, the immersion duration of 44.23 min is the minimum time required to achieve probit-9 control efficacy of the most heat-tolerant stage at 50ºC. The HWT schedules did not have any discernible effect on the quality parameters of the respective commodities after treatment. The differential gene expression analysis of T. leucotreta larvae under thermal stress revealed several genes including heat shock proteins, cytochrome P450, cuticle proteins, odorant binding proteins, and immune system genes that may be associated with the T. leucotreta's ability to withstand cold and heat. Overall, this study provides a basis for the standardization and subsequent adoption of quarantine treatment protocols for Tommy Atkins mango, French beans, and bell pepper against quarantine pests, B. dorsalis, F. occidentalis, and T. leucotreta, respectively.In Afrika südlich der Sahara sind Mango (Mangifera indica L.), Buschbohnen (Phaseolus vulgaris L.) und Paprika (Capsicum annuum L.) drei wirtschaftlich bedeutende Gartenbaukulturen. Trotz ihrer wirtschaftlichen und ernährungsphysiologischen Bedeutung werden ihre Produktion und ihr Handel durch verschiedene Einschränkungen behindert; die wichtigste davon ist der Befall durch verheerende Quarantäneschädlinge wie die Orientalische Fruchtfliege (Bactrocera dorsalis), den Westlichen Blütenthrips (Frankliniella occidentalis) und den Falschen Apfelwickler (Thaumatotibia leucotreta). Gegen diese Schädlinge wurden Maßnahmen zur Vorerntebekämpfung entwickelt und umgesetzt. Da sie jedoch in vielen Einfuhrländern als A1- und A2-Schädlinge gelten, sind Maßnahmen nach der Ernte erforderlich, um die Quarantänesicherheit in diesen Ländern zu gewährleisten. Vor diesem Hintergrund zielte diese Studie darauf ab, (1) Protokolle für die Heißwasserbehandlung nach der Ernte von Tommy Atkins Mango, Brechbohnen und Paprika gegen B. dorsalis, F. occidentalis bzw. T. leucotreta zu entwickeln, (2) die Auswirkungen der Heißwasserbehandlungsverfahren auf die Qualität der behandelten Waren zu bewerten und (3) die unterschiedliche Genexpression von T. leucotreta bei extremen Temperaturbehandlungen zu erforschen. Die Ergebnisse der HWT zur Nachernte-Entwesung von Tommy Atkins Mango gegen B. dorsalis zeigen, dass das dritte Larvenstadium das hitzetoleranteste Stadium von B. dorsalis ist und dass die Mindestzeit, die erforderlich ist, um seine Probit-9-Kontrollwirkung (99.9968 % Mortalität) zu erreichen, bei 46.1ºC, 72.63 Minuten beträgt. Die Ergebnisse der HWT für die Entwesung von Bohnen nach der Ernte gegen F. occidentalis-Eier zeigen, dass 8.01 Minuten die minimale Eintauchzeit ist, die erforderlich ist, um eine Probit-9-Kontrollwirkung bei 45°C zu erreichen. Bei der Bewertung der Wirksamkeit der HWT als phytosanitäre Behandlung von T. leucotreta in Paprika ist die Eintauchdauer von 44.23 Minuten die Mindestzeit, die erforderlich ist, um bei 50ºC eine Probit-9-Kontrolle des hitzetolerantesten Stadiums zu erreichen. Die HWT-Zeitpläne hatten keine erkennbaren Auswirkungen auf die Qualitätsparameter der jeweiligen Waren nach der Behandlung. Die differenzielle Genexpressionsanalyse von T. leucotreta-Larven unter thermischem Stress ergab mehrere Gene, darunter Hitzeschockproteine, Cytochrom P450, Kutikulaproteine, Geruchsstoffbindungsproteine und Gene des Immunsystems, die möglicherweise mit der Fähigkeit von T. leucotreta, Kälte und Hitze zu widerstehen, in Verbindung stehen. Insgesamt bietet diese Studie eine Grundlage für die Standardisierung und anschließende Einführung von Quarantänebehandlungsprotokollen für Tommy Atkins Mango, Bohnen und Paprika gegen die invasiven Schädlinge B. dorsalis, F. occidentalis bzw. T. leucotret
Co-design of retrofitted Nature-based Solutions for decentralized greywater treatment in urban areas of Costa Rica
No full textThe water quality of urban rivers in Latin America is increasingly degraded by the discharge of untreated wastewater. One of the main challenges in the region is achieving sustainable management of urban wastewater to restore river ecosystems. In Costa Rica, water supply networks serve more than 94% of the population; however, only an estimated 14% of wastewater is properly treated. The lack of adequate sanitation infrastructure has led to widespread use of septic tanks and the discharge of untreated greywater into rivers, contributing to the environmental degradation of surface waters. Retrofitting conventional centralized sewer networks and treatment plants into existing urban areas poses significant social, economic, and technical challenges. This research explores the application of Nature-based Solutions (NbS) as alternative decentralized technologies for retrofitting greywater treatment in urbanized areas. The inherent complexity of social-ecological dynamics in urban environments necessitates an inter- and transdisciplinary approach to address this challenge. To conduct this research, a Real-World Lab was established in the Greater Metropolitan Area of Costa Rica, employing a transdisciplinary approach. This provided a physical space and social context to integrate site-specific aspects and understand the various factors influencing the implementation of NbS. Co-design and prototyping of NbS were key methods used to develop knowledge and achieve results. The findings demonstrate the technical potential of NbS for decentralized greywater treatment. However, limitations exist in the governance frameworks and financing mechanisms required to implement and scale up NbS as a decentralized technology across the country. This research offers insights into the requirements for the widespread implementation of NbS, which can be applied to other regions facing similar sanitation retrofitting challenges in Latin America