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Starmerella bombicola is known to produce sub‐terminally hydroxylated lactonic sophorolipids (SLs), while Candida kuoi synthesizes acidic open chain SLs with terminally hydroxylated fatty acids. Upon feeding glucose and fatty alcohols both strains form long‐chain nonionic SLs. According to structure elucidation the SLs consist of a hydroxylated fatty acid esterified with fatty alcohol and linked via a glycoside bond to the diacetylated sophorose unit. Palmityl, stearyl, and oleyl alcohols lead to products with lipid chain lengths of C32 or C36. Oleyl alcohol is the preferred substrate leading to 45 g L−1 of the double unsaturated C36 SL with S. bombicola and 20 g L−1 with C. kuoi. Scale up from shake flask to 1.5 L fermentations is possible and 65 g L−1 long‐chain SLs are obtained with S. bombicola within 7 days. Mixed feeding of oleic acid and a variety of fatty alcohols leads to new long‐chain SLs. In the presence of oleic acid the yeasts do not oxidize the fatty alcohol and thus the production of biosurfactants with tailored chain length is possible. The long‐chain SLs show good emulsification ability of water/paraffin oil mixtures at low energy input and reduced interfacial tension significantly.
Practical Applications: Sophorolipids are produced by fermentation on industrial scale focusing on cleaning and detergent applications. Mainly lactonic or anionic open‐chain forms are used today. The new long‐chain SLs presented in this manuscript are accessible with existing production technology and can be produced with high titers from cost‐efficient renewable raw materials. In contrast to the commercial products the long‐chain SLs are more hydrophobic and exhibit a strong emulsification behavior. Therefore they have the potential to broaden the application range of SLs in future. They may be useful as novel emulsifiers for cosmetic creams and lotions, pharmaceutical ointments and food products or may find application in oil spill remediation.
Urbanization processes are one of the main factors for habitat loss and fragmentation, driving global biodiversity loss and species extinction. The neotropical Atlantic forest in Brazil is considered a global key biodiversity hotspot and used to be one of the most extensive forests of the Americas. Due to substantial deforestation over centuries, its landscape was transformed into a mosaic of small forest fragments surrounded by a predominantly agricultural matrix. Urban expansion and rural urbanization have created peri-urban zones, which still can harbor natural habitat remnants,
contributing to biological diversity and thus providing essential ecosystem services to urban and rural areas. The maintenance of such ecosystem services requires an understanding of the ecological processes in the ecosystem. A prerequisite for such an in-depth insight is the quantification of the underlying ecosystem functions. The ecosystem function pest control, a trophic interaction between insectivorous birds and herbivorous arthropods, was quantified in an empirical study using artificial caterpillars as prey models. This technique allows the identification of predator groups and the assessment of their predation rates. A total of 888 plasticine caterpillars were distributed at eight sites in secondary forest fragments surrounding the university campus of the federal university of São Carlos (UFScar) in peri-urban Sorocaba, southeastern Brazil. In sixteen point counts, 72 insect-eating birds, belonging to 19 species, were identified as possible artificial caterpillar attackers. Local habitat variables were measured to describe the forest vegetation structure and the landscape context. The study aimed to assess which structural components of the
forest fragments, together with the recorded bird community variables (abundance, richness, αdiversity), best explain the estimated predation rates by birds. The mean predation rate for birds was 8.25 ± 6.3 % for a reference period of eight days, representing the first quantification of the ecosystem function pest control for the study area. The three treatments of caterpillar placement heights (ground, stem: 0.5 -1.0 m, leaf: 1.5 - 2.0 m) were the best and only estimator to explain bird
predation rates. The little dense understory and ground vegetation might have facilitated the accessibility of artificial caterpillars, especially for carnivorous arthropods and birds. The detected contrast in their foraging and predation patterns suggests that arthropods and birds complement each other in their function of pest control. Bird predation rates were found to be negatively related to the vegetation structure. Thus, more open habitats, with less understory and low tree density, but high canopy cover and including dead trees were correlated with the highest predation rates and also exhibited more specialized forest-dependent bird species. This study confirms the importance of the maintenance of forest fragments in peri-urban areas, even if they are small, to preserve forest-associated birds, to contribute to the biological diversity on a broader scale, and to prevent the loss of ecosystem functions and services, mitigating some of the adverse effects of urbanization. Further investigation of the effect among the three treatments of caterpillar
placement on the predation rates is encouraged, including comparative studies among different habitat types. For future studies, it is recommended to model the avian community variables with the vegetation structure measures to predict habitat preferences of insectivorous birds. Therefore, the sampling of more units and on a bigger scale, including over a more extended period, is necessary to improve the robustness of the results, which could provide the basis for a monetary analysis of the ecosystem service pest control by birds.
The increasing public awareness of business related impacts on environmental and social well-being, be it positive or negative, are nowadays key drivers of corporate success. Internal and external business environments exert pressure and force transparency as well as responsible action in terms of resolving environmental and social impacts. In line with this, Porter and Kramer regard business behaviour that addresses societal needs and challenges, as the “new way to achieve economic success”.
However, whereas some companies “remain trapped in an out-dated approach to value creation” and restrict their CSR commitment to the compliance with governmental regulation, others proactively address stakeholder needs. By addressing these needs, companies can benefit from grasping the opportunity of enhanced cost efficiency and lowered risk or gaining competitive advantages through establishing unique value propositions, in a way that meets stakeholder demands. Apart from that, CSR performance can be seen as powerful tool to successfully influence stakeholder perceptions in terms of reputation, and thus an exceptional source of value creation. In addition to this, organisations can profit from win-win-win situations related to syncretic value creation by means of partnering with stakeholders. This, however, implies expanding the focus of cost- and risk-reduction towards increasing competitiveness through creating mutual benefits for environment, society and the economy alike.
Although a growing number of companies have recognised the advantages coming along with Corporate Social Responsibility engagement, the accompanying efforts have not been sufficiently mature yet. Due to the fact that many organizations apply a rather narrow and out-dated approach to value creation, they fail to achieve a balance between environmental, social and economic objectives. This, in turn, implies a restriction in their ability to exploit the full value creation potential that is related to CSR engagement. But even organisations applying a broader perspective of value creation, struggle to internalise the opportunities. This is mainly due the challenge of balancing and integrating economic and non-economic criteria. At the same time, organizations are facing the challenge of getting support from senior management and staff. Thus, in order to profit from adopting a ‘broad perspective’, firms must build a deep understanding of the benefits resulting from mutual value creation. However, the main challenge remains the systematic and strategy related integration of Corporate Social Responsibility strategies into core business processes. In respect to this, organizations have to take into account that “social and environment performance are almost certainly unique to each organization”. Thus, value creation in terms of CSR has to be understood as a highly complex set of cause-an-effect relationships among mediating variables and situational contingencies, which is too specific to rely on poorly structured and generic approaches.
In brief, organisations seem to struggle establishing an understanding that does not consider environmental, social and economic benefits as mutually exclusive. Notwithstanding, that such an understanding is established the complexity of factors influencing Corporate Social Responsibility impedes to balance between economic and non-economic criteria. Furthermore, organisations have difficulties to strategically integrate, manage and measure environmental and social performance drivers as well as outcome measures.
Stable recombinant mammalian cells are of growing importance in pharmaceutical biotechnology production scenarios for biologics such as monoclonal antibodies, growth and blood factors, cytokines and subunit vaccines. However, the establishment of recombinant producer cells using classical stable transfection of plasmid DNA is hampered by low stable gene transfer efficiencies. Consequently, subsequent selection of transgenic cells and the screening of clonal cell populations are time- and thus cost-intensive. To overcome these limitations, expression cassettes were embedded into transposon-derived donor vectors. Upon the co-transfection with transposase-encoding constructs, elevated vector copy numbers stably integrated into the genomes of the host cells are readily achieved facilitating under stringent selection pressure the establishment of cell pools characterized by sustained and high-yield recombinant protein production. Here, we discuss some aspects of transposon vector technologies, which render these vectors promising candidates for their further utilization in the production of biologics.
Mental illnesses in adolescence and young adulthood are steadily increasing. Thus,mental disorders represent an individual and societal challenge and an enormous health economicburden, creating an urgent need for research and action. Mental health problems are omnipresent inthe life of young people and the internet is the first resource, which helps them to understand theirsituation. Young people with migration background often have more difficulties accessing health careservices. Digital technologies offer an ideal opportunity for a low-threshold platform that addressesthe needs of young people. The current project “GeKo:mental” aims to design a multilingual websitefor Cologne-based adolescents and young adults that will enable them to obtain comprehensiveinformation about mental illness and health, treatment options and first contact points. To designthis website, this study aims to find out what kind of health information is needed and how itshould best be presented. Nine focus group discussions with adolescents and young adults withand without migration background (N = 68) were conducted; the focus group discussions took placeat schools, in an association for social youth work and in an cultural association, which is linkedto a mosque in Cologne, Germany. A qualitative content analysis was conducted on the gatheredmaterial. The participants reported concrete challenges and needs. The results will form the basis forthe development and design of a website.
This thesis proposes four different Augmented Reality (AR) display techniques that can overcome the problem of uncertain tracking errors. Where most other papers focus on limiting the amount of error that a user tracking system generates, this paper pro-poses visualizations that limit their impact instead. For this, four different display techniques have been developed and evaluated using criteria found in related literate. Two of the four proposed solutions consistently ranked better within these criteria. The first, Bending Words, uses a mix between spatially registered information and turn instructions to achieve that result. The second, WIM, mostly relies on context infor-mation of the building instead.
Academic search systems aid users in finding information covering specific topics of scientific interest and have evolved from early catalog-based library systems to modern web-scale systems. However, evaluating the performance of the underlying retrieval approaches remains a challenge. An increasing amount of requirements for producing accurate retrieval results have to be considered, e.g., close integration of the system’s users. Due to these requirements, small to mid-size academic search systems cannot evaluate their retrieval system in-house. Evaluation infrastructures for shared tasks alleviate this situation. They allow researchers to experiment with retrieval approaches in specific search and recommendation scenarios without building their own infrastructure. In this paper, we elaborate on the benefits and shortcomings of four state-of-the-art evaluation infrastructures on search and recommendation tasks concerning the following requirements: support for online and offline evaluations, domain specificity of shared tasks, and reproducibility of experiments and results. In addition, we introduce an evaluation infrastructure concept design aiming at reducing the shortcomings in shared tasks for search and recommender systems.
Polyimides rank among the most heat-resistant polymers and find application in a variety of fields, including transportation, electronics, and membrane technology. The aim of this work is to study the structural, thermal, mechanical, and gas permeation properties of polyimide based nanocomposite membranes in flat sheet configuration. For this purpose, numerous advanced techniques such as atomic force microscopy (AFM), SEM, TEM, TGA, FT-IR, tensile strength, elongation test, and gas permeability measurements were carried out. In particular, BTDA–TDI/MDI (P84) co-polyimide was used as the matrix of the studied membranes, whereas multi-wall carbon nanotubes were employed as filler material at concentrations of up to 5 wt.% All studied films were prepared by the dry-cast process resulting in non-porous films of about 30–50 μm of thickness. An optimum filler concentration of 2 wt.% was estimated. At this concentration, both thermal and mechanical properties of the prepared membranes were improved, and the highest gas permeability values were also obtained. Finally, gas permeability experiments were carried out at 25, 50, and 100 ◦C with seven different pure gases. The results revealed that the uniform carbon nanotubes dispersion lead to enhanced gas permeation properties.
Emergency management services, such as firefighting, rescue teams and ambulances,are all heavily reliant on road networks. However, even for highly industrialised countries such asGermany, and even for large cities, spatial planning tools are lacking for road network interruptionsof emergency services. Moreover, dependencies of emergency management expand not only onroads but on many other systemic interrelations, such as blockages of bridges. The first challenge thispaper addresses is the development of a novel assessment that captures systemic interrelations ofcritical services and their dependencies explicitly designed to the needs of the emergency services.This aligns with a second challenge: capturing system nodes and areas around road networksand their geographical interrelation. System nodes, road links and city areas are integrated into aspatial grid of tessellated hexagons (also referred to as tiles) with geographical information systems.The hexagonal grid is designed to provide a simple map visualisation for emergency planners andfire brigades. Travel time planning is then optimised for accessing city areas in need by weighingimpaired areas of past events based on operational incidents. The model is developed and testedwith official incident data for the city of Cologne, Germany, and will help emergency managers tobetter device planning of resources based on this novel identification method of critical areas.