Emission free propulsion for ships

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Water management and new clean technologies in Africa: A review of Compotherm

Challenges in water management are becoming more severe in many countries and this is exacerbated by climate change. With the increase of environmental threats, a new market for clean tech companies is emerging on the global scheme. The majority of these companies are small and medium seized companies (SME) under rapid growth. This paper is investigating the clean-tech product Compotherm. Two market overviews of the global solar thermal market as well as the portable water purification market will be shown. Which market- based factors are vital for the products potential success? What current competitors are there? This paper will also study the current needs of water clean technologies in Africa by conducting and reviewing a series of interview. Findings show that the interest for thermal water heaters is growing in both a local and international view. Compotherm could be seen as plazed in the middle of two traditional product categorise within the market. in the market of portable purification systems the potential success of new products is dicussed upon. In order to survive in the rapid emerging business companies are have shown to market there product for a specific clientele.Challenges in water management are becoming more severe in many countries and this is exacerbated by climate change. With the increase of environmental threats, a new market for clean tech companies is emerging on the global scheme. The majority of these companies are small and medium seized companies (SME) under rapid growth. This paper is investigating the clean-tech product Compotherm. Two market overviews of the global solar thermal market as well as the portable water purification market will be shown. Which market- based factors are vital for the products potential success? What current competitors are there? This paper will also study the current needs of water clean technologies in Africa by conducting and reviewing a series of interview. Findings show that the interest for thermal water heaters is growing in both a local and international view. Compotherm could be seen as plazed in the middle of two traditional product categorise within the market. in the market of portable purification systems the potential success of new products is dicussed upon. In order to survive in the rapid emerging business companies are have shown to market there product for a specific clientele

Endometriosis : involvement of stem cells and clinical impact

Introduction: Endometriosis is a common gynaecological disease affecting up to 10% of women of reproductive age. The women suffer from severe abdominal pain and infertility as a consequence of the chronic inflammation. The disease has also been associated with an increased risk of cancer, in particular endometrial and ovarian cancer. Endometriosis represents an important socioeconomic burden as the condition is associated with productivity loss, medical and surgical treatments including assisted reproduction, and a compromised quality of life. The pathophysiology of endometriosis is not fully understood, and as of today we are unable to identify women at risk for cancer development and offer them a tailor-made prophylactic treatment. Aims: The overall aim of this thesis is to explore some of the mechanisms that have an important influence on clinical impact, in particular infertility and the risk of developing endometriosis-associated cancer. The mechanisms enabling endometriotic lesion establishment are explored in an in vitro experimental model and the methylation profile of the fertility-regulating gene HOXA10 is investigated in eutopic and ectopic endometrium. This study also attempts to identify the molecular link between endometriotic stem cells and the development of ovarian cancer by exploring CSC-specific markers and their molecular signatures, and gene expression profile of cancer-correlated molecules in different endometrial compartments. Results: Significant changes were found in the endometrium of women with endometriosis compared to healthy controls. The first study demonstrated the expression of ApoE, ITGB2, ITGB7, LAMC1, CD24, and JAM-1 in women with and without endometriosis. Also, some of the molecules showed a significant altered expression upon comparing endometrium from women with and without endometriosis, as well as eutopic and ectopic endometrium of women with endometriosis. ApoE and JAM-1 were decreased in both proliferative and secretory phase in endometrium from women with endometriosis, and mRNA expression of LAMC1 was reduced in endometrium from endometriosis patients compared with controls in the proliferative phase. CD24 expression was significantly expressed in eutopic and ectopic endometrium in women with endometriosis. In the second study, we found a significant hypermethylation of the HOXA10 gene in eutopic secretory endometrium in women with endometriosis compared with controls. When comparing the methylation profile in patients suffering from ovarian endometriosis with patients presenting extra-ovarian disease, we could not demonstrate any significant correlation between methylation status and stage of disease. The third study demonstrated that mesenchymal endometrial stem cells from women with endometriosis showed an active S-phase as well as an up-regulation of PTEN, VEGF-α, and decreased BCL2 gene-expression compared to controls. A subset of potentially ‘high-risk’ patients could be identified showing a significant up-regulation of genes involved in reprogramming SOX2, NANOG; cancer metabolism TP53, K-ras; and epithelial- mesenchymal transition genes TGF-α and SNAI1. TP53 turned out to play the role of a master regulator. When comparing monolayer to 3D spheroid cultures, an increased coexpression of CSC surface markers CD44 and CD133 was seen, and the chemo-sensitivity assay performed in a 3D-tumour microenvironment revealed increased tumour invasion in the ‘high-risk’ group. In the fourth study, we found a significant difference in the expression of genes that correlated with endometrial malignant transformation in both endometrial stromal and glandular compartments in endometriosis patients compared with controls. Conclusions: Our results shed light on the molecular linkage to the etiology of endometriosis and malignant transformation of endometriosis, as well as providing useful information relevant to endometriosis-associated infertility and pathogenesis

Congenitally decorticate children's potential and rights

This article is the first indepth ethical analysis of empirical studies that support the claim that children born without major parts of their cerebral cortex are capable of conscious experiences and have a rudimentary capacity for agency. Congenitally decorticate children have commonly been classified as persistently vegetative, with serious consequences for their well-being and opportunities to flourish. The paper begins with an explication of the rights-based normative framework of the argument, including conceptual analysis of the terms ‘agency’, ‘potentiality for agency’ and ‘gradual approach of agency’. It critically examines Alan Gewirth’s account of the criteria for being a rights bearer and principles for settling rights conflicts between agents and potential agents. It then applies the rights-based normative framework to the ethical challenges associated with care for congenitally decorticate children. It argues that recent empirical studies support the claim that the concepts ‘potential for agency’ and ‘capacity for rudimentary agency’ apply to children who are born without major parts of their cerebral cortex. The article finally discusses important medical ethical implications of these results. It specifically focuses on congenitally decorticate children’s preparatory rights to a stimulating intellectual and social environment

Zinc recovery from Waste-to-Energy fly ash – A pilot test study

Zinc recovery from MSWI fly ash using acidic leaching and chemical precipitation was studied at pilot scale. The leached fly ash was re-incinerated in order to destroy toxic dioxins. 75–150 kg/h of fly ash from a Swedish Waste-to-Energy plant was mixed with scrubber liquids from the same flue gas treatment system in a continuously stirred vessel. The resulting slurry was dewatered in a vacuum belt filter. Hydroxide precipitation of the produced leachate, at a pH of around 9, followed by filtration of the formed crystals in a membrane filter press produced a filter cake with up to 80 wt% Zn(OH)2 in dry solids, calculated from Zn(tot). Up to 70% of the zinc content in the fly ash could be recovered. Two 4-hour full scale ash re-incineration tests were performed: leached fly ash was mixed with the waste at a ratio corresponding to a situation where all the fly ash was continuously re-incinerated. The tests showed only an 8% mass increase of produced fly ash, which means that most of it ended up in the bottom ash, although some elements could potentially accumulate in the system if all the fly ash was to be continuously re-incinerated. No negative effects were observed on the bottom ash quality, which suggests that a large portion of the toxic fly ash could be transformed into the bottom ash fraction

Utvärdering av energi och miljöindex för sjöfart

Increased demand for environmental, energy and sustainability information on products in a life cycle perspective has led to the development of a large number of different voluntary initiatives aimed at communicating the environmental performance of sea transport, such as databases, indices, labels and certificates. There is however a lack of scientific studies that applies the research area of environmental indices to shipping. The majority of previous studies on environmental indices for shipping have focused on comparing indices or to find successful parameters for developing a new index. This study has conducted an inventory of environmental initiatives applicable for communicating environmental performance of ships and shipowners. It has then identified and evaluated voluntary initiatives that are based on an indexing system; defined as ‘environmental performance indices’. The evaluation was conducted on three indices based on principal aspects and criteria found in literature. The results of the inventory showed a large diversity of 38 environmental performance initiatives related to a diversity of stakeholders. They had different scope, target groups and applications. Most existing initiatives are based on a set of environmental requirements or standards, where specific installed equipment, operational measures, management aspects or compliance with environmental legislation are rewarded in one way or another. Such rewards could be score points or for example reduced port dues. Some initiatives were however based on environmental performance data such as specific emission levels. Many further focused on air emissions and energy efficiency or carbon dioxide emissions. Ten initiatives were identified as environmental performance indices, though their inclusion within this definition was later discussed in further analysis. The following three indices were evaluated: (1) the Energy Efficiency Operational Indicator developed by the International Maritime Organization, (2) the Performance Metrics Tool developed by Clean Cargo Working Group, and (3) the Clean Shipping Index developed by the Clean Shipping Project. The indices each assess environmental performance based on data for individual vessels, which then is aggregated into a final index. The last two indices use scoring systems for different environmental areas and include performance requirements. These indices could be used for a shipowner to benchmark and market environmental performance of their ships, and for a transport buyer to select the ships and shipowners according to their performance results. Third-party verification exists for all three indices, which provides quality control of the data used for the performance assessment. It was concluded that the three indices have many similarities, though they show a large variation in their construction and application. The varieties of the three indices could be explained by the variety of stakeholders connected to them. It was concluded that the properties of a particular index depend on the indented use, which in turn depends on the intended users and the developer of the index. It was further concluded that the variety of different initiatives is problematic and shows a need for global standardized methods. The study could contribute to bring order to the variety of concepts of the different initiatives associated with environmental ship indices. It could also identify potential uses and users of the indices. In addition, it could be one way of solving methodological problems of comparison between different indices identified in earlier studies

Development of a combined mean value-zero dimensional model and application for a large marine four-stroke diesel engine simulation

In this article, a combined mean value–zero dimensional model is developed using a modular approach in the computational environment of Matlab/Simulink. According to that, only the closed cycle of one engine cylinder is modelled by following the zero-dimensional approach, whereas the cylinder open cycle as well as the other engine components are modelled according to the mean value concept. The proposed model combines the advantages of the mean value and zero-dimensional models allowing for the calculation of engine performance parameters including the in-cylinder ones in relatively short execution time and therefore, it can be used in cases where the mean value model exceeds its limitations. A large marine four-stroke Diesel engine steady state operation at constant speed was simulated and the results were validated against the engine shop trials data. The model provided results comparable to the respective ones obtained by using a mean value model. Then, a number of simulation runs were performed, so that the mapping of the brake specific fuel consumption for the whole operating envelope was derived. In addition, runs with varying turbocharger turbine geometric area were carried out and the influence of variable turbine geometry on the engine performance was evaluated. Finally, the developed model was used to investigated the propulsion system behaviour of a handymax size product carrier for constant and variable engine speed operation. The results are presented and discussed enlightening the most efficient strategies for the ship operation and quantifying the expected fuel savings

Learning from eLearning: Emerging Constructive Learning Practices

This research is situated within the field of Information and Communication Technologies for Development (ICT4D) and asks if ICT use can make learning practices change. While constructive learning practices are critical to both individual and societal development, repetitive learning practices are the norm in many developing countries. The study is based on observations and in-depth interviews and uses a structurational approach to understand if and how students views of learning change during an e-learning program in Sri Lanka. We found four constructive learning practices that emerged through technology use; individual exploring, interaction with peers, interaction with teachers, and taking responsibility of the learning. Many constructive learning practices emerged outside the LMS used, in students’ voluntary uses of publicly available resources on the Internet. The study shows that technology use can play a positive role for development, provided an open environment is available; students learn constructive practices from e-learning