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Achieving urban water security is a major challenge for many countries. While several studies have assessed water security at a regional level, many studies have also emphasized the lack of assessment of water security and application of measures to achieve it at the urban level.
Recent studies that have focused on measuring urban water security are not holistic, and there is still no agreed-upon understanding of how to operationalize and identify an assessment framework to measure the current state and dynamics of water security. At present, there is also no clearly defined and widely endorsed definition of urban water security. To address this challenge, this study provides a systematic approach to better understand urban water security, with a working definition and an assessment framework to be applied in peri-urban and urban areas. The proposed working definition of urban water security is based on the United Nations (UN) sustainable development goal on water and sanitation and the human rights on water and sanitation. It captures issues of urban-level technical, environmental, and socio-economic indicators that emphasize credibility, legitimacy, and salience.
The assessment framework depends on four main dimensions to achieve urban water security: Drinking water and human beings, ecosystem, climate change and water-related hazards, and socio-economic factors (DECS). The framework further enables the analysis of relationships and trade-off between urbanization and water security, as well as between DECS indicators. Applying this framework will help governments, policy-makers, and water stakeholders to target scant resources more eff ectively and sustainably. The study reveals that achieving urban water security requires a holistic and integrated approach with collaborative stakeholders to provide a meaningful way to improve understanding and managing urban water security.
Aerobic microbial cultivations are industrially important group of processes and pose challenges for the reactor design. In particular, estimation of industrial scale conditions is difficult from laboratory and pilot scale data. Due to complex interaction of gas/liquid phase hydrodynamics, mass transfer parameters and microbial metabolism, both improvement of modelling tools and reactor design are desired. We present an approach to estimate growth conditions in industrial scale reactor by combining black-box metabolic models with CFD-model.
The reactor type used here is Outotec OKTOP9000®, which is used in the industrial hydrometallurgical processes at 900 m3 scale. It is adopted to a laboratory setting and compared to stirred tank reactor (STR) in gas dispersion, mass transfer and yeast cultivation experiments. In addition, a kinetic model for the yeast growth is developed based on literature sources and validated by the laboratory scale batch cultivations. This kinetic model is used along with CFD-model that is developed to describe the flow and mass transfer conditions in the industrial scale reactor.
The laboratory scale experiments show the feasibility of OKTOP9000® reactor when compared to STR, particularly with improved gas handling capacity. The modelling approach shows qualitatively similar behavior in the large scale simulations when compared to laboratory scale cultivations.
The southeast of Córdoba province used to be originally covered by hundreds of wetlands that got heavily modified or drained in the last few decades. Since wetlands provide various important ecosystem services (ESS) for human well-being, their degradation created several problems in La Picasa basin, among which floods are the most obvious one. The wise use of wetlands is increasingly acknowledged to be part of nature-based solution approaches reducing disaster risk. However, in the study area these approaches remain a relatively new concept to decision makers and the lack of knowledge on their effectiveness and implementation process poses a serious barrier to their adoption.
To overcome this obstacle, this dissertation applies an ESS perspective on the current problems of La Picasa basin and sets it in a context of socio-ecological system (SES) theory. A comprehensive analysis of (1) the role wetlands have played in the historic development of the SES, (2) important stakeholder dynamics that create opportunities or restrictions for the conservation of wetlands and (3) possible management approaches to inverse negative ESS trade-offs and feedback loops, was performed.
Results demonstrate that the current problems of floods have both natural and anthropogenic causes. In this regard, wetlands hold a vital role in the complex historic interactions between the social and ecological drivers of changes in the water balance. Although a social network between stakeholders exists, several conflicts prevent a proper functioning of a basin-wide integrated management concept based on wetland restoration. Nature-based solution approaches, putting wetlands in the center of attention of future management strategies, were found to hold a high potential to reduce the risk of floods and, as a side-effect boost biodiversity and habitat quality in the study area.
This market research paper has been prepared under the supervision of Prof. Dr. Wolfgang Veit of TH Köln and Prof. Dr. Carol Scovotti of University of Wisconsin-Whitewater in the course of the inter-university cross-border collaboration student research project “Export Opportunity Surveys (EOS)”. This study explores organic lipstick export opportunities to the German and US markets.
The whole site of the waste disposal centre Leppe in Lindlar has been modified by the project :metabolon into an authentic learning site for knowledge transfer. Addressing all age groups, the project offers insights into environmental knowledge and explains contexts of resources and material flows. The site conditions allow practical outlooks on future energy systems. Following the meta theme of “lifetime learning”, pupils and students are addressed by different modules, considering their individual learning levels.
While global food production greatly exceeds dietary energy demand, undernutrition remains, and diets largely fail to ensure the health of the population. Agricultural biodiversity is crucial for the world’s food security, but genetic diversity has been degraded. In Mexico, the dietary transition towards processed foods has contributed to malnutrition and a rise of diet-related chronic diseases. Mexico’s indigenous people are conserving and creating valuable plant genetic resources in their swidden milpas and traditional agroforestry systems but remain the country’s most vulnerable population group. The Teenek (or Huastec), an indigenous group that habitat the Huasteca Potosina, a region in north-eastern Mexico cultivate a high diversity of edible plants in their home gardens (solar), milpas, and agroforestry systems (te’lom, or finca). However, migration has been leading to the abandonment of traditional farming in the region.
The objective of this study was to analyse if the managed agricultural biodiversity of the different traditional land use systems contributes to the food security of the farming households in the community of Jol Mom. Food availability and access were investigated. In total, 40 households were surveyed. Dietary patterns were identified through principal component analysis. Informal interviews, semi-structured interviews and participant observation allowed to account for the people’s own perceptions and provided additional insights. Findings showed that traditional Teenek farming systems are the source of a variety of nutritious foods and resulted to be the most important provider of fruits and vegetables. The average production diversity was 34 out of 56 crops, farmers cultivating more than one or two farming systems showed an increase of four and 11 produced species respectively. Production diversity was strongly correlated with food variety in a household’s diet, with an increment of one per 0.85 produced crop. Two main diverging dietary patterns were revealed, a westernized diet relying largely on purchased foods, to which the younger generation was more inclined, and a traditional diet characterized by a high consumption of cultivated products, mostly observed in the older households.
In conclusion, farming households in Jol Mom profit from the agricultural diversity of their production systems, either through the consumption of nutritious foods or by the sale of agricultural products. However, a tendency towards nutrient-poor diets was observed. Increasing agricultural diversity and consumption of locally produced foods might help to fight this trend but would require a valorisation of traditional foods and an appreciation of the contribution of indigenous people’s traditional agriculture to food security.
Due to the worldwide shortage of petrochemical based resources, the usage of renewable bio-based raw materials for established and novel products becomes increasingly important.[1] Such bio-based resources are already used for the fabrication of a variety of products, e. g. paper, lubricants, detergents or cosmetics. In the future they are expected to emerge in many more applications in industry and household.[1]
A very promising approach relies on the use of glycolipids as a source of hydroxy-oleic acid.[2] Microbial glycolipids are produced for instance via fermentation from natural resources such as plant oils and sugar.[3] After fermentation complex product mixtures are obtained with the composition depending on the microorganism, substrate and fermentation time.[3] The successful use of microbial glycolipids and hydroxy-oleic acid (HOA) derived therefrom as bio-based intermediates requires reliable analytical methods as well as robust manufacturing processes for the synthesis and cleavage of bio-based molecules. In order to obtain hydroxy-oleic acids as bio-based intermediates, the acidic cleavage of microbial derived sophorolipid was investigated. In addition the implementation of HOA in polyurethane (PU) systems was explored.
Web browsers use HTTP caches to reduce the amount of data to be transferred over the network and allow Web pages to load faster. Content such as scripts, images, and style sheets, which are static most of the time or shared across multiple websites, are stored and loaded locally when recurring requests ask for cached resources. This behaviour can be exploited if the cache is based on a naive implementation. This paper summarises possible attacks on the browser cache and shows through extensive experiments that even modern web browsers still do not provide enough safeguards to protect their users. Moreover, the available built-in as well as addable cache controls offer rather limited functionality in terms of protection and ease of use. Due to the volatile and inhomogeneous APIs for controlling the cache in modern browsers, the development of enhanced user-centric cache controls remains -until further notice- in the hands of browser manufacturers.
Metallic tubular micro-components play an important role in a broad range of products,
from industrial microsystem technology, such as medical engineering, electronics and optoelectronics, to sensor technology or microfluidics. The demand for such components is increasing, and forming processes can present a number of advantages for industrial manufacturing. These include, for example, a high productivity, enhanced shaping possibilities, applicability of a wide spectrum of materials and the possibility to produce parts with a high stiffness and strength. However, certain difficulties arise as a result of scaling down conventional tube forming processes to the microscale. These include not only the influence of the known size effects on material and friction behavior, but also constraints in the feasible miniaturization of forming tools. Extensive research work has been conducted over the past few years on micro-tube forming techniques, which deal with the development of novel and optimized processes, to counteract these restrictions. This paper reviews the relevant advances in micro-tube fabrication and shaping. A particular focus is enhancement in forming possibilities, accuracy and obtained component characteristics, presented in the reviewed research work. Furthermore, achievements in severe plastic deformation for micro-tube generation and in micro-tube testing methods are discussed.
REST became the go to approach when it comes to large scale distributed systems on, or outside the World Wide Web. This paper aims to give a brief overview of what REST is and what its main draws and benefits are. Secondly, I will showcase the implementation of REST using HTTP and why this approach became as popular as it is today. Based on my research I concluded that REST’s advantages in scalability, coupling, performance and its seamless integration with HTTP enabled it to rightfully overtake classic RPC based approaches.
Resilience in relation to flood risk management (FRM) is not a new concept, yet parts of the FRM community are still struggling to apply it. The main challenge this study addresses is the question as to whether parts of the FRM community should still adopt, or rather “leap‐frog,” resilience. The main purpose is to evaluate whether resilience is a still on‐going trend or, already subsiding. Research suggests that resilience is an on‐going trend that connects research and policy and has gained international recognition as expressed by international guidelines and bodies promoting its research but also its operationalization. Academic literature in the area of FRM also shows a significant continuing development. Resilience enables to analyze dynamics and transformations of riverine areas, or coastal zones in connection to an integrated social‐environmental system approach with more emphasis and conceptual basis than previous concepts. Resilience is more than a short‐lived notion and it appears that FRM researchers cannot avoid addressing it. Resilience often is a convergence of ideas and mainstreaming of efforts, which in many venues is absolutely necessary and can help, for example, to decrease silo‐thinking. But as academics, we have a mandate to remain skeptical and remain on the look‐out for novel ideas, too.
This article is categorized under:
Engineering Water > Planning Water
Pseudozyma antarctica Lipase B catalyzed esterification and transesterification in deep eutectic solvents (DES) was investigated in reaction systems with alcohols of different polarity. Coconut oil and crude biodiesel were deacidified successfully with non-immobilized CALBL and final acid values of 1.2 for biodiesel and 0.5 for coconut oil were obtained, while no esterification with ethanol was observed without DES. Water depletion of the lipid phase in the presence of water adsorbing DES causes this difference. Analysis of water contents revealed a 10 fold lower water content of the lipid phase in the presence of a second DES phase than in trials without utilization of DES. In contrast reactions of hydrophilic polyols are suppressed in the presence of DES. While the esterification of fructose and the transesterification with glycerol worked well in the polar solvent 2-methyl-2-butanol, almost no fructose esterification and a decreased transesterification with glycerol were observed in the presence of DES. Analysis of logP values of the substrates explains the substrate dependent differences in reactivity. The polar alcohols are probably bound strongly in the hydrogen-bonding network of the DES phase and are thus not available for lipase catalyzed reactions.
Before transporting the landfill leachate to municipal wastewater treatment plant it has to be treated in a landfill leachate treatment plant, as it comprises high concentrations of ammonium. The elimination of ammonium load in the leachate is usually done by the combined processes of nitrification and denitrification with a specially adapted biocenosis in the activated sludge (AS). For each of the steps, specialized bacteria such as Nitrosomonas, Nitrobacter and Paracoccus are used to transfer the ammonia to gaseous nitrogen. The aim of this investigation was to find suitable process parameters for a complementary treatment of fermentation water from a biogas plant together with landfill leachate. The processed water of the biogas plant consists of a higher concentration of ammonium and carbon sources or easily degradable volatile fatty acids. It can save the usage of external carbon source (acetic acid) and additionally it could also compensate the missing volumes of leachate in times of low rain and low leachate flows. To maintain the high workload for the existing leachate treatment pilot plant (LTPP), a combined treatment of landfill leachate and process water is also of economic and of ecological interest. The long-term adaption process of the biocenosis needs to be done step-by-step. Innovative process monitoring is needed to prevent biocenosis collapse. In our study, we present our set-up, a closer look at the ongoing experiment and the long-term changes in the biocenosis.
The 12th Annual Meeting of the Sponsoring Group Reinsurance [Förderkreis Rückversicherung] was held 5th July 2019 in Niederkassel, near Cologne. Some 80
representatives of the (re)insurance companies involved in the Sponsoring Group took part in the meeting, along with guests. Offered for the fifth time as part of the
Annual Meeting, the Researchers’ Corner gave eight members of academic staff at the Cologne Research Centre for Reinsurance an opportunity to deliver a presentation on their respective current research projects. In three sessions – each featuring 2-3 parallel lectures with posters – the most important results of the scientific studies by the Cologne Research Centre for Reinsurance were presented and discussed. The heterogeneity of the topics presented by academic staff reflects the dovetailing of Cologne Research Centre with reinsurance practice.
Session 1
a) Manuel Dietmann (M.Sc.): The increasing importance of the riskmanagement function in insurance companies
b) Robert Joniec (M.Sc., FCII, cand. PhD): How is the reinsurance cycle doing?
c) Wolfgang Koch (M.Sc., FCII): Information asymmetries between reinsurance brokers and assignors
Session 2
a) Jörg Dirks (M.Sc., FCII): Unmanned aircraft – Evolution of the market for aviation (re-)insurance
b) Fabian Lassen (M.Sc., FCII): Reducing volatility through use of an insurance swap
c) Fabian Pütz (M.Sc., cand. PhD): Transferring cat risks from emerging markets from a macroeconomic perspective Session 3
a) Kai-Olaf Knocks (M.A., FCII): The ILS market in 2019 – discouragement or wait-and-see?
b) Lihong Wang (M.Sc., FCII, cand. PhD): China InsurTech development
With the publication series, ‘Proceedings of the Researchers’ Corner’, the Cologne Research Centre for Reinsurance meets the desire for publication of the research results of our scholars together with the accompanying posters and discussions. The titles are reproduced in keeping with the above agenda of the Researchers’ Corner for the 12th Annual Meeting of the Sponsoring Group Reinsurance. As part of the event, Prof. Materne also conducted an interview with Mr Ingo Wichelhaus (Senior Director, Mount Street) on the topic of risk management and portfolio management. Particular attention was devoted to the broad spectrum of risk for financing in the shipping sector.
Soils are complex, evolving systems that simultaneously shape and are shaped by numerous biotic and abiotic factors in a vast web of interactions that creates the conditions for the propagation of life and the maintenance of human societies. Yet, land use and land use change (LULUC) and anthropogenic climate change (CC) are forcing substantial and rapid alterations into soil’s properties and processes, thus affecting the functions and services derived from it. The resulting land degradation (LD) is now spread, according to recent estimates, over nearly 30 % of the world’s total land, mostly on the population dense and impoverished tropics, a zone predicted to withstand the worst impacts of CC. The Atlantic Forest in Brazil is a particularly vulnerable environment, and the unusual drought of 2014-2017 that hit its Southeastern region is likely the harbinger of a progressively drier future.
The way the prelude of what might be an increasingly frequent hazard affected farmers’ livelihoods and natural resources, and the manner in which they reacted to those impacts can thus reveal points of strength and fragility that could be respectively harnessed or addressed to develop a more sustainable agriculture and climate resilience. This master thesis focused on characterizing those impacts and reactions on distinct dairy production systems in two municipalities in Northwestern Rio de Janeiro: Santo Antônio de Pádua and Cambuci. Through interviews and in loci observations, the researcher collected data concerning environmental services (erosion prevention, soil cover and water provision), production variables (inputs and outputs), socio-economic information, farm system management and farmers’ future perspectives. The results show that dairy production systems in the region are heterogeneous and, although they may share common characteristics, drought outcomes were closely tied to the specificities of each farm. Ultimately, outcomes originated from differences in water supply, water demand, and feed availability, their subsequent change by the drought and farmers’ reaction to those changes at each property.
For use in a landfill, a laboratory reactor for safe and environmentally friendly biological utilization of low-concentration methane gas will be further developed. The current principle of denitrification-coupled aerobic methane oxidation will be replaced by methane oxidation under anaerobic conditions. Anaerobic methane oxidation offers the advantage that, in addition to methane, nitrate also undergoes biodegradation. Another advantage is that the oxygen content can be significantly lower. This reduces the risk of the formation of an explosive atmosphere in the reactor. Currently, the principle of anaerobic methane oxidation is known. However, organisms capable of doing so are not yet available as a pure culture. Therefore, several biomasses were probed for the ability of anaerobic methane oxidation. It was found that moor-heavy sediment, activated sludge from the leachate treatment plant and biomass from the local biogas plant oxidize methane after the natural carbon source (C source) was been removed.
This project is focused on the generation of hardware independent code for PLCs and the comparison for energy consumption patterns of hydraulic and electric drive unit. This works is dedicated to MLC (mould level control) in a continuous casting machine, which is used to cast steel slabs continuously. The code generation is done with the help of the PLC coder which is present in the software Simulink. The programming is done entirely in MATLAB. The application of the generated code is tested on the Siemens S7-1500 PLC. For executing the code and the development of the HMI (human machine
interface) Siemens software TIA Portal V15 has been used. Moreover, for further analysis of signals and testing the code, a PDA or process data acquisition system, IBA system is used. For energy analysis also the IBA system is used.
Multidrug resistance (MDR) in tumors and pathogens remains a major problem in the efficacious treatment of patients by reduction of therapy options and subsequent treatment failure. Various mechanisms are described to be involved in the development of MDR with overexpression of ATP-binding cassette (ABC) transporters reflecting the most extensively studied. These membrane transporters translocate a wide variety of substrates utilizing energy from ATP hydrolysis leading to decreased intracellular drug accumulation and impaired drug efficacy. One treatment strategy might be inhibition of transporter-mediated efflux by small molecules. Isocoumarins and 3,4-dihydroisocoumarins are a large group of natural products derived from various sources with great structural and functional variety, but have so far not been in the focus as potential MDR reversing agents. Thus, three natural products and nine novel 3,4-dihydroisocoumarins were designed and analyzed regarding cytotoxicity induction and inhibition of human ABC transporters P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1) and breast cancer resistance protein (BCRP) in a variety of human cancer cell lines as well as the yeast ABC transporter Pdr5 in Saccharomyces cerevisiae. Dual inhibitors of P-gp and BCRP and inhibitors of Pdr5 were identified, and distinct structure-activity relationships for transporter inhibition were revealed. The strongest inhibitor of P-gp and BCRP, which inhibited the transporters up to 80 to 90% compared to the respective positive controls, demonstrated the ability to reverse chemotherapy resistance in resistant cancer cell lines up to 5.6-fold. In the case of Pdr5, inhibitors were identified that prevented substrate transport and/or ATPase activity with IC50 values in the low micromolar range. However, cell toxicity was not observed. Molecular docking of the test compounds to P-gp revealed that differences in inhibition capacity were based on different binding affinities to the transporter. Thus, these small molecules provide novel lead structures for further optimization.
In the degradation of ammonia (NH4+) to gaseous nitrogen (N2), the nitrification is one of the two reaction steps. The nitrification itself is divided in two steps and is performed by two different types of bacteria. Current literature has shown that there are types of bacteria, which have the genetic equipment to perform both steps in one bacteria. Nevertheless, in wastewater and landfill leachate treatment, ammonia-oxidizing organisms (AOO) and nitrite-oxidizing organisms (NOO) occur as a symbiosis. The intermediate of the two consecutive reaction steps (NO2-, nitrite) is toxic. For this reason, both steps are necessary for the two bacterial groups. To determine the ratio of AOO, NOO and heterotrophic bacteria (which use organic compounds as carbon and energy source) the oxygen uptake rate (OUR) with selective inhibition with N-allylthiourea (ATU) and azide is used. In the inflow of a pilot plant in one street a step by step increased amount of a process water out of a fermentation plant was added to the landfill leachate. For comparison, the other street was supplied only with landfill leachate with the same amount of nitrogen. As a result, comparable values for the different bacterial groups and reproducible results were measured and lead to a better understanding of the analysed nitrification sludge. Deeper understanding of the behavior of the different groups will result in a reduce risk of malfunctions and a more stable operation in the wastewater or landfill leachate treatment plant.
In the last few decades raw material molasses, used in large scale fermentations in the production of bioethanol, citric acid, (baker´s) yeast and yeast extracts, has become more and more expensive. That is why agro-industrial wastes have become an interesting alternative. They are being produced in large volumes every day and represent a serious environmental problem considering its high organic content. The present contribution aims to demonstrate how waste products of wine production can be employed as substrate in bioethanol production. Cultivation of yeast and bioethanol production on molasses and grape pomace extract was studied in flasks in laboratory scale. This work should be regarded as an example of integrated sustainability which demonstrates how the waste from one industrial process is used as feedstock for another.