The 10 most recently published documents
Cameroon’s forests are rich in endemic plant and animal species but remain among the most threatened ecosystems in Central Africa. To safeguard its forest heritage, the government resorted to the establishment of protected areas and relied on laws and other regulatory instruments to protect them. However, the integrity of protected areas such as the Campo Ma’an National Park is increasingly compromised by growing pressure to exploit natural resources nearby the park. Large-scale infrastructure projects like the Camvert agro-industrial project, the Kribi deep seaport, the Memve’ele hydropower dam including forests and mining concessions have intensified habitat loss thus accelerating biodiversity decline around the park. These projects have generated cumulative impacts on wildlife resources including rising poaching, illegal trade in endangered species, loss of indigenous farmlands, and increased risks of zoonotic diseases in surrounding communities. Amid these pressures, concerns have emerged regarding the effectiveness of conservation laws to preserve the park’s ecological integrity. Balancing biodiversity conservation with economic development in the park’s buffer zones remains a major governance challenge. This dissertation evaluates the implementation of Environmental and Social Impact Assessment in addressing conservation concerns linked to the Camvert agro industrial project and its effects on the Campo Ma’an National Park and adjacent communities. Legal analytical methods including mixed quantitative and qualitative approaches were employed for data collection, supported by field observations and semi-structured interviews. The research findings reveal that, development initiatives nearby the park including settlement expansion significantly contribute to forest degradation and biodiversity loss. Specifically, the Camvert project was implemented largely without the free, prior, and informed consent of local and indigenous communities as required by Article 20(1) of the 2013 EIA law in Cameroon. The study further indicates shortcomings in the government’s compliance with international environmental obligations. Nonetheless, conservation actors including WWF and the African Wildlife Foundation have strengthened anti-poaching efforts and supported community livelihood initiatives. The research concludes that integrating indigenous rights, local knowledge systems and participatory land-use planning into EIA processes is essential for sustainable biodiversity conservation. Strengthening alternative livelihoods, ecotourism, and environmental education will enhance protection of the Campo Ma’an National Park while supporting inclusive development and poverty reduction in Cameroon.
Biofouling remains a critical challenge in membrane bioreactors (MBR), which is primarily caused by the production of extracellular polymeric substances (EPS) as an initial step in biofilm formation. This still limits their widespread application in wastewater treatment. In the past decades, much research has been carried out to understand and consequently reduce biofouling in MBR. More recent studies have focused primarily on inhibiting the release of EPS by applying quorum quenching (QQ) to control biofouling in MBR. This study presents the first investigation of the QQ potential of Rubellimicrobium mesophilum and its effects on biofilm inhibition by EPS re-duction, which is demonstrated for MBR operated with submerged flat sheet (PTFE, PS) and hollow fibre polyvinylidene fluoride (PVDF) membranes operated in parallel for 114 days. The QQ effect has a significant impact on the reduction of biofilm thickness on PTFE membranes by 45% and on PS membranes by about 47% respectively. Additionally, the performance of PVDF was improved by 287.5%. Similarly, the total protein concentration on the PTFE membranes was reduced by 57%, while on the PS membranes, the reduction was 78%. In mixed liquor, protein reduction was 55%, indicating its effectiveness in controlling biofouling over extended operation. The biofilm formation was monitored by measuring the biofilm thickness via fluorescence microscopy and by analyzing the protein and sugar content of the developing biofilm and of the mixed liquor. All parameters proved a decreasing biofilm formation with increasing amounts of entrapped QQ bacteria, while the removal efficiency of organic compounds and ammonia remained similar between all MBRs.
This study explores how the globalisation of Indigenous human rights is reshaping nature conservation within the UNESCO World Heritage regime and challenging the enduring legacies of “green colonialism.” Building on environmental-historical accounts of fortress conservation and on Indigenous critiques of exclusionary protected-area politics, the study expands Thomas Schmitt’s cultural-geographic approach to UNESCO World Heritage by including the perspective of a global nature conservation regime in which competing conservation paradigms are negotiated. It asks (1) how the global institutionalisation of Indigenous rights norms, especially the 2007 UN Declaration on the Rights of Indigenous Peoples, contests exclusionary conservation practices in World Heritage, and (2) how paradigm competition transforms power relations between Indigenous peoples and the institutional complex of States Parties, Advisory Bodies, and the World Heritage Centre.
The analysis combines world society theory, figurational sociology, and decolonial approaches to trace shifting dependencies, normative isomorphism, and the coloniality of knowledge in World Heritage decision-making. Empirically, the dissertation employs a historical and regional comparative approach across four sites: Manú National Park (Peru), Tongariro National Park (Aotearoa/New Zealand), Lake Bogoria (Kenya), and Pimachiowin Aki (Canada). A qualitative content analysis of official UNESCO records from 1987 to 2023 (including World Heritage Committee decisions, Advisory Body evaluations, State of Conservation reports, nomination files, and management plans) is conducted.
Findings show an uneven institutionalisation of Indigenous rights across cases and over time. While formal references to participation and Indigenous human rights have expanded, implementation often remains partial, reflecting a persistent decoupling between normative commitments and conservation practice. Nevertheless, the regime displays limited but notable openness to human rights-based and inclusive conservation, particularly when Indigenous actors and human rights institutions intervene. Overall, the study argues that the World Heritage regime has become a contested platform for addressing historical injustices and that its legitimacy increasingly depends on Indigenous-led approaches to the designation and management of World Heritage properties. Methodologically, it demonstrates how UNESCO’s repository of official records can be used to reconstruct organisational “documentary realities” and trace institutional change comparatively.
Diese Masterarbeit wurde als Qualifikationsarbeit für den M. A. Soziale Arbeit an der BTU Cottbus-Senftenberg eingereicht und untersucht die Rolle von Männlichkeitsanforderungen in (extrem) rechten Gruppenzusammenhängen. Grundlage ist eine genderreflektierende Analyse des autobiografisch geprägten Romans „Nullerjahre. Jugend in blühenden Landschaften“ von Hendrik Bolz. Im Mittelpunkt steht die Frage nach der Bedeutung von Männlichkeit in Bezug auf die Hinwendung in extrem rechte Gruppenzusammenhänge mit einem Fokus auf die männliche Sozialisation in Ostdeutschland in den sogenannten Baseballschlägerjahren. Die Analyse orientiert sich an der Grounded Theory. Theoretisch erfolgt eine Orientierung an Ansätzen der kritischen Männlichkeitsforschung, welche mit historischen, sozialräumlichen sowie gesellschaftlichen Kontextfaktoren der Nachwendezeit verknüpft werden. Im Ergebnis eröffnet die Analyse einen differenzierten Blick auf rechte Jugendgewalt: Sie betrachtet die Anschlussfähigkeit an (extrem) rechte Gruppierungen in der Transformationszeit in Ostdeutschland aus dem Zusammenspiel von männlicher Sozialisation, kollektiver Zugehörigkeit und spezifischen sozioökonomischen, kulturellen und sozialen Bedingungen. Die Arbeit leistet einen Beitrag zur geschlechterreflektierenden Forschung zu Rechtsextremismus, indem sie verdeutlicht, dass Männlichkeitsanforderungen und hypermaskuline Selbstinszenierungen zentrale Orientierungspunkte innerhalb (extrem) rechter Gruppenzusammenhänge darstellen. Sie betont darüber hinaus die Bedeutung sozialräumlicher Verankerungen und langfristiger habitueller Prägungen für Radikalisierungs- und Distanzierungsprozesse und markiert damit präventive Ansatzpunkte für sozialpädagogische Handlungsfelder.
Synergistic enhancement of PFOA and 6:2-FTAB photodegradation using Au/Y-doped TiO2 nanocatalysts
(2026)
Efficient degradation of perfluoroalkyl substances (PFAS) requires photocatalysts capable of promoting strong CF bond cleavage and selective interfacial charge transfer. In this proof-of-concept-study, a dual-doped TiO2 nanophotocatalyst (Au2/Y5/P25) was synthesized by combining gold (Au) nanoparticles and yttrium (Y) dopants to enhance charge separation and reactive oxygen species (ROS) generation. Structural characterization supported Au deposition on the TiO2 surface and Y incorporation into the lattice, accompanied by a slight bandgap narrowing. Under UV irradiation in aqueous solution (unbuffered pH 5.8, room temperature) the nanophotocatalyst exhibited distinct degradation pathways for 1000 μg L-1 of two representative PFAS, perfluorooctanoic acid (PFOA) and Capstone B (6:2 FTAB), reflecting environmentally prevalent groups. PFOA underwent 99 % degradation within 100 min via a stepwise CF2-cleavage mechanism, generating a sequence of perfluorocarboxylic acids down to perfluorobutanoic acid (PFBA), consistent with enhanced electron-hole separation. In contrast, Capstone B showed rapid, single-step S-N bond cleavage to 6:2 perfluorooctanesulfonic acid (6:2 PFOS), primarily driven by hole- and •OH-mediated oxidation under oxygen-rich conditions. This process achieved 96 % degradation within 20 min but did not proceed to further defluorination, indicating oxidative limitations. Dissolved oxygen analysis revealed efficient electron utilization and sustained oxidative turnover without excessive oxygen depletion. The findings demonstrate that Au/Y co-doping promotes selective PFAS activation, enabling rapid precursor oxidation while exposing the kinetic limits of secondary C-F bond cleavage. These discoveries offer new insights into the design of plasmonic-rare-earth-modified TiO2 photocatalysts for efficient PFAS degradation through interface-driven oxidation pathways.
UNESCO guidelines for the management of historic cities and World Heritage (WH) sites have pointed out that urban heritage can foster social cohesion. Scholars have also suggested that heritage has the potential to (positively) influence social cohesion. However, it remains unclear how this outcome can be achieved. A central challenge is that social cohesion is a contested and mouldable concept that is subject to interpretations and can encompass diverse notions. Hence, before exploring how urban heritage can contribute to social cohesion, it was necessary to investigate what social cohesion can mean in the context of urban heritage. Using discursive institutionalism as a theoretical foundation and integrating perspectives from critical heritage studies, this research examines how social cohesion notions are articulated in discursive repertoires in UNESCO documents that framed the nomination and management of urban areas inscribed as WH between 2017 and 2021. The analyses and discussions of the investigation were structured using a conceptual framework that integrates eleven recurrent notions considered part of or necessary for social cohesion – which in this research are called constituents of the concept – and three typologies into which social cohesion constructs can be grouped: relational, ideational, and distributive.
This research demonstrates that the analysed UNESCO documents articulate multiple notions related to the constituents and typologies of social cohesion. These notions are articulated in various discursive repertoires and provide opportunities to use WH processes to promote social objectives. As for the relational typology, which focuses on fostering and maintaining social relations, the UNESCO documents articulate notions that encourage interaction and enable the regulation and protection of social dynamics. Turning to the ideational typology of social cohesion, which focuses on reinforcing identities, the processes for the identification of Outstanding Universal Values and designation of WH cities move towards critical approaches that acknowledge the power of heritage to shape the acceptance and othering of the many groups converging in cities. In this way, WH can help negotiate and promote intragroup and intergroup social cohesion in cities. Finally, regarding the distributive typology of social cohesion, which aims to address disparities, although the UNESCO guidelines and heritage experts acknowledge unwanted impacts of WH designations related to inequality, such as gentrification and commodification processes, recommendations or statements enabling the use of WH to recognise and address disparities are rarely articulated.
The course “How to talk about “nature”?” is offered every winter semester to an average of 125 students at the Brandenburg University of Technology Cottbus-Senftenberg. As part of the course, students have the opportunity to critically question and rethink the concept of “nature” and some of its derivative notions, such as “nature as wilderness.” After examining how this notion has led to an artificial separation between humanity and a supposedly “human-free nature,” students recognize the limitations of this duality. Through an in-depth exploration of the historical and cultural roots of this notion of “nature as wilderness”, students are then invited to share their experiences of “wilderness” that challenge this duality. Here we have compiled a selection of their responses from the winter semesters 20/21 and 21/22.
Quorum quenching (QQ) is a promising biological approach that has the potential to control membrane biofouling. However, the implementation of the QQ membrane bioreactor still requires a more systematic and comprehensive understanding, including the selection of membrane materials, the determination of the optimal QQ bacterial dosage, and the use of appropriate media for the immobilization of QQ bacteria, all of which are important to ensure long-term operation. The present study investigated the impact of QQ bacteria on biofilm formation across different polymeric membranes. These include flat sheet membranes, Polytetrafluoroethylene (PTFE), Polysulfones (PSs), and hollow-fibre polyvinylidene difluoride (PVDF) membranes. It also evaluated biofilm development, membrane filtration performance, extracellular polymeric substance (EPS) production, and sludge floc properties, which were characterized using fluorescence microscopy. The results revealed that QQ intervention markedly suppressed quorum sensing (QS), leading to a pronounced, dose-dependent reduction in biofilm thickness, membrane fouling, EPS production and sludge floc size. Biofilm thickness was reduced by 63.5% on PTFE and 55.4% on PS membranes, accompanied by a notable reduction in EPS protein and polysaccharides, thereby weakening the biofilm formation and enhancing membrane filterability. Therefore, the permeability performance of the PVDF membrane improved by 338.2%. Furthermore, sludge settleability was enhanced, and floc size was reduced, resulting in the mitigation of biofilm formation without impacting pollutant degradation. These findings elucidate the material-dependent and dose-responsive mechanism by which QQ regulates EPS synthesis and biofilm formation in MBR.
Improving facial expression recognition in realistic environments using deep learning approaches
(2025)
Facial expressions are vital channels of non-verbal communication, conveying rich information about emotional and cognitive states in social interactions. Enabling intelligent systems to automatically recognize these expressions makes Facial Expression Recognition (FER) a key task in affective computing. Despite significant progress, existing FER methods still face limitations in effectively and efficiently recognizing facial expressions under real-world conditions, such as those found in driving environments or dynamic, in-the-wild scenarios.
This thesis addresses these challenges by proposing several novel deep learning-based models that improve the performance, robustness, and efficiency of FER systems. To this end, several contributions are presented. The work begins with a comprehensive review of FER, highlighting persistent challenges in the field, particularly within the driving context. Subsequently, DFER-GCViT, a Vision Transformer-based architecture tailored for driver FER, is introduced to improve recognition accuracy under conditions of occlusion, pose variation, and lighting changes. To enhance computational efficiency, ShuffViT-DFER is proposed, a lightweight hybrid model that combines convolutional and transformer-based pretrained networks. Furthermore, multimodal approaches are explored using Vision-Language Models (VLMs), particularly CLIP. CLIVP-FER is developed to integrate visual and textual features, enhancing semantic understanding in the driving context. The research then shifts toward general dynamic FER, leveraging parameter-efficient fine-tuning and temporal modeling of CLIP, and maintains strong performance with reduced computational cost through the proposed PE-CLIP.
Extensive experiments on benchmark datasets demonstrate the effectiveness of the proposed models across diverse and challenging conditions. The results underscore the importance of optimizing architectures, incorporating multimodal cues, and enabling lightweight FER systems suitable for practical deployment.
