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Today many of the most popular service provides such as Netflix, LinkedIn, Amazon and others compose their applications from a group of individual services. These providers need to deploy new changes and features continuously without any downtime in the application and scale individual parts of the system on demand. To address these needs the usage of microservice architecture has grown in popularity in recent years. In microservice architecture, the application is a collection of services which are managed, developed and deployed independently. This independence of services enables the microservices to be polyglot when needed, meaning that the developers can choose the technology stack for each microservice individually depending on the nature of the microservice. This independent and polyglot nature of microservices can make developing a single service easier, but it also introduces significant operations overhead when not taken into account when adopting the microservice architecture. These overheads include the need for extensive DevOps, monitoring, infrastructure and preparation for distributed system fallacies. Many cloud-native and microservice based applications suffer from outages even with thorough unit and integration tests applied. This can be because distributed cloud environments are prone to fail in node or even regional level, which cause unexpected behavior in the system when not prepared for. The applications ability to recover and maintain functionality at an acceptable level in these unexpected faults, also known as resilience, should also be tested systematically. In this thesis we give a introduction to the microservice architecture. We inspect an industry case where a leading banking company suffered from issues regarding resiliency. We examine the challenges regarding resilience testing microservice architecture based applications. We compose a small microservice application which we use to study the defensive design patterns and tools and methods available to test microservice architecture resiliency.

Methane(CH4) is a powerful greenhouse gas and even though the CH4 concentrations in the atmosphere have been increasing rapidly since the year 1750, there still remains large uncertainties in the individual source terms to the global CH4 budget. Measuring the isotopic fractions from various CH4 sources should lead to new knowledge on the processes involving CH4 formation and emission pathways. Nowadays stable isotope measurements for various CH4 sources are quite routinely made, but radiocarbon measurements have for long been too expensive and time consuming. For this reason a new CH4 sampling system for radiocarbon measurements was developed at the Laboratory of Chronology of University of Helsinki. The system allows sampling directly from the atmosphere or from different environmental sources using chambers. To demonstrate the functionality of the system it was tested and optimized in various laboratory experiments and in the field. The laboratory measurements showed that before combustion of CH4 to carbon dioxide(CO2), ambient carbon monoxide(CO) and CO2 can be removed from the sample gas by a flow for more than 10 hours with a flowrate of 1 l/min. After the CO and CO2 removal the CH4 in the sample gas is combusted to CO2. The combustion efficiency for CH4 was 100% with a flowrate of 0.5 l/min. After CH4 is combusted to CO2 it is then collected to molecular sieves and can be later on analyzed using accelerator mass spectrometer. The laboratory measurements, however, showed that due to adsorption of nitrogen(N2) to the molecular sieves, the 1g of molecular sieve material used in molecular sample sieve tubes was not sufficient for low concentration samples where the sampling times are very long. In the field, CH4 was collected from the atmospheric ambient air at Hyytiälä SMEAR II station, Juupajoki, Finland, and from tree and soil chambers. The radiocarbon content of the atmospheric CH4 was 102.27 ± 0.02 percent Modern Carbon (pMC) and 101.40 ± 0.02 pMC. These values were much lower than the expected values, indicating a large spatial and temporal variability. The CH4 collected from chambers closed around tree-stems had a radiocarbon content had of 113.60 ± 0.37 pMC, which was slightly higher than the 108.71 ± 0.37 pMC measured from soil chambers located in the nearby Siikaneva peatland. This indicated that a larger amount of CH4 emitted from peatland surface was recently fixed near the soil surface and a larger amount of the CH4 emitted from tree-stem surface was from older origin transported via roots from the deeper depths of the soil. There is, however, a possibility that the lower radiocarbon content from the peatland surface emitted CH4 was due to a significant contribution from old CH4 fixed before bomb effect, and which is diffused from deeper depths of the soil. This would explain the results from the autumn campaign where the radiocarbon contents were 91.84 ± 0.03 during nighttime and 104.26 ± 0.03 pMC during daytime. These results also indicated that during the daytime more of the emitted CH4 is fixed near the surface of the peatland soil. One additional CH4 sample was collected in January 2019 from the atmospheric ambient air at Kumpula, Helsinki, Finland using a significantly larger molecular sample sieve. This sample had a radiocarbon content of 52.40 ± 0.21 pMC. The old carbon in the sample originated from a fossil methane used in earlier laboratory experiments and indicated that the regeneration process for the larger sample sieve was incomplete. Overall the system functions very well, while collecting samples from environmental chambers, as the CH4 concentrations are left to build-up before collecting the sample. For atmospheric samples, for which the sampling times are higher, the sample sieve size and the regeneration time and temperature will have to be further investigated. In the future, more measurements of the radiocarbon content for individual CH4 sources are needed to provide better knowledge on the CH4 pathways. This portable system allows an efficient way to collect CH4 samples for radiocarbon analyzes from various locations.

This thesis studies the current level of environmental management in the Ship Power business division within Wärtsilä corporation and aims to identify the related development needs. Hitherto environmental management has been mainly coordinated at the corporate level and implemented in local companies distributed geographically. Due to the recent organizational changes, however, the significance of division level environmental management in Ship Power has increased. The research goal is approached by examining the central elements of corporate environmental management and the challenges that the organizational structure places for it. Based on the findings, suggestions for further actions are given in order to develop the environmental management in Ship Power. Empirical data was collected through 35 qualitative interviews with Wärtsilä employees from different functions, business lines, and local companies in order to get a comprehensive view of environmental management in the Ship Power related activities. The interviews were semi-structured in order to provide answers for certain areas of concern, but also to enable the disclosure of topics not defined by the interviewer. The data is categorized into themes according to the theoretical background, and its analysis is based on inductive reasoning. Based on the findings, the environmental management in Ship Power is divided into two dimensions. The product-related environmental questions are handled in the business lines and the operational issues in the local companies. This fragmentation of the environmental knowledge causes inconsistent environmental focus at different organizational levels, and creates challenges to information sharing across the organization. The lack of corporate instructions on the environmental management system implementation has led to diverse practices in the local companies, and the lack of standardized documentation makes the internal comparison between them difficult. Therefore the experience gained from the local management systems does not support organizational learning throughout the corporation. While the product-related environmental aspects are the core of the business strategy, more attention could be paid to operational environmental management in Ship Power. For instance, the sharing of environmental knowledge could be strengthened in order to enhance employee awareness of the corporate practices and to facilitate the discussion of the best practices between the local units. A standardized documentation system would facilitate internal benchmarking and provide a means for centralized environmental performance follow-up. Because the local management systems are not sufficient to cover the global business processes, it would also be important to identify the environmental aspects in the Ship Power division. Furthermore, visible communication of the common environmental targets would help to create consistent environmental focus in Ship Power.

Catcher-protein and Tag-peptide originate from split CnaB domains of Gram-positive bacteria surface proteins, which are stabilized by spontaneous intramolecular isopeptide bonds formed between lysine and asparagine residues. However, there is a limited number of non-cross-reacting Catcher and Tag pairs available where the reaction occurs close to the diffusion limit, and which can be used in multiple fragment ligation to construct recombinant fusion proteins. Therefore, a new Catcher/Tag system – LplCatcher/LplTag – was developed in our group from CnaB domain of Lactobacillus plantarum. However, the ligation efficiency of this pair needs to be improved to expand the application possibilities. Therefore, there is a need for efficient library screening method, which allows to detect improved protein-peptide pairs where the covalent interaction takes place rapidly. In this study a new high-throughput in-vivo screening system was developed for visualizing the ligation of Catcher/Tag fusion proteins using splitFAST fluorogenic reporter system for detecting the phenotype, and Fluorescence-activated cell sorting (FACS) for separating the variants at single cell level based on fluorescence intensity. splitFAST is a system engineered by splitting a fluorescent protein named Fluorescence-Activating and absorption-Shifting Tag (FAST) into CFAST and NFAST. The system can be utilized in visualizing the protein interactions because once NFAST and CFAST associate, in the presence of a fluorogen, they form the active and highly fluorescent FAST protein. Herein, Catcher-protein was fused with CFAST and Tag-peptide with NFAST, which allowed detecting the Catcher-Tag ligation ratio based on fluorescence with splitFAST system. Next, a screening system was developed for detecting Catcher variants with improved ligation efficiency. The developed high-throughput screening system showed high potential since visualizing the protein ligation was possible, and hence the system could help in expanding the Catcher/Tag toolbox by allowing large mutant library analyzes.

As the virtual world grows more complex, finding a standard way for storing data becomes increasingly important. Ideally, each data item would be brought into the computer system only once. References for data items need to be cryptographically verifiable, so the data can maintain its identity while being passed around. This way there will be only one copy of the users family photo album, while the user can use multiple tools to show or manipulate the album. Copies of users data could be stored on some of his family members computer, some of his computers, but also at some online services which he uses. When all actors operate over one replicated copy of the data, the system automatically avoids a single point of failure. Thus the data will not disappear with one computer breaking, or one service provider going out of business. One shared copy also makes it possible to delete a piece of data from all systems at once, on users request. In our research we tried to find a model that would make data manageable to users, and make it possible to have the same data stored at various locations. We studied three systems, Persona, Freenet, and GNUnet, that suggest different models for protecting user data. The main application areas of the systems studied include securing online social networks, providing anonymous web, and preventing censorship in file-sharing. Each of the systems studied store user data on machines belonging to third parties. The systems differ in measures they take to protect their users from data loss, forged information, censorship, and being monitored. All of the systems use cryptography to secure names used for the content, and to protect the data from outsiders. Based on the gained knowledge, we built a prototype platform called Peerscape, which stores user data in a synchronized, protected database. Data items themselves are protected with cryptography against forgery, but not encrypted as the focus has been disseminating the data directly among family and friends instead of letting third parties store the information. We turned the synchronizing database into peer-to-peer web by revealing its contents through an integrated http server. The REST-like http API supports development of applications in javascript. To evaluate the platform s suitability for application development we wrote some simple applications, including a public chat room, bittorrent site, and a flower growing game. During our early tests we came to the conclusion that using the platform for simple applications works well. As web standards develop further, writing applications for the platform should become easier. Any system this complex will have its problems, and we are not expecting our platform to replace the existing web, but are fairly impressed with the results and consider our work important from the perspective of managing user data.

Background and objectives: First, this research aims to understand Ghanaian student teachers' genuine thoughts and views on remote education and learning. Secondly, the interest is to find out how the student teachers see the use of remote methods in their future work and especially, how to teach practical skills remotely. Third, the broader goal is to take a stand on the development of teacher education in a time where sustainability issues, developing technology and crises challenging the global world are shaking up our world view in a new way. The bicycle model of the future home economics teacher, which guides systemic thinking and is based on a transformative learning concept, adapted for this study, is used to help the examination of the results. To support future orientation, the data is also examined with the help of 21 century competencies on teaching and learning. Finally, this master's thesis is an article-form thesis, and its purpose is to produce a scientific article, as well as this summarizing section describing the background work and research process of the article. Context: The concept of remote teaching and learning used in this study refers specifically to learning and teaching that takes place online with remote connections. Such learning can be real-time or asynchronized learning through online platforms. These do not necessarily require a constant network connection but rely on digital pedagogy. Methods: The data of this qualitative online study was collected through WhatsApp interviews and the informant group consisted of nine Ghanaian student teachers. The research data has been analyzed with theory-based content analysis, using the bicycle model on comprehensive climate education as a guiding theory. The bicycle model was modified from the original to suit this study. Results and conclusion: The results of this study clearly indicate both that remote teaching and learning has become a permanent part of Education, but also that remote methods, related to technological knowledge and interaction skills should be further developed in teacher education. The informants of the study saw an interactive, communal, and learning environment that utilizes peer learning but also takes individuals into account as particularly meaningful when thinking about their own learning but also their future work as a teacher.

Ethiopia is Africa's biggest coffee exporter nation with deep history. Coffee discovered in Ethiopia and it continues to be pivotal for the country in many fronts till to date. The coffee linkage with Ethiopia is deep-rooted many historians believe back in 9th century coffee discovered by Kaldi, a goat herder. He discovered it after noticing coffee's energizing effect on his goats. The word coffee itself also derived from place called 'Kaffa' where the trees blossomed. Coffee gradually became a world obsession by spreading from highlands of Ethiopia traveled along spice routes to Yemen, Turkey and Europe. Coffee exporting is a significant portion of Ethiopian economy. It accommodates more than twenty five million peasants which indicate its magnitude for the country. It is one of the leading sources of income for the government and other stakeholders. The establishment of Ethiopian Commodity Exchange (ECX) has seen the Ethiopian coffee trade system being transformed. It created a platform of primary, secondary and tertiary market divisions. In a way that the coffee can be traded based on value addition from one division to the other. Unlike the previous centralized warehousing system, it introduced decentralized warehousing and liquoring centers across the country where the coffee quality checked by use of laboratory tasting. It gives a temporary produce storage services until the coffee is sold and ownership of the produce transferred from seller to buyer. The introduction of modernized and transparent system enabled economic gain and helped farmers to enhance their life conditions. The objective of this study was to identify some of the contradictions that are solved in Ethiopian coffee trade activity by the establishment of ECX. In addition, the emerging contradictions and prevailing disturbances at present as well as the overall benefits it brought in relation to farmers' day to day life conditions were analyzed.

Children’s height and weight development remains a subject of interest especially due to increasing prevalence of overweight and obesity in the children. With statistical modeling, height and weight development can be examined as separate or connected outcomes, aiding with understanding of the phenomenon of growth. As biological connection between height and weight development can be assumed, their joint modeling is expected to be beneficial. One more advantage of joint modeling is its convenience of the Body Mass Index (BMI) prediction. In the thesis, we modeled longitudinal data of children’s heights and weights of the dataset obtained from Finlapset register of the Institute of Health and Welfare (THL). The research aims were to predict the modeled quantities together with the BMI, interpret the obtained parameters with relation to the phenomenon of growth, as well as to investigate the impact of municipalities on to the growth of children. The dataset’s irregular, register-based nature together with positively skewed, heteroschedastic weight distributions and within- and between-subject variability suggested Hierarchical Linear Models (HLMs) as the modeling method of choice. We used HLMs in Bayesian setting with the benefits of incorporating existing knowledge, and obtaining full posterior predictive distribution for the outcome variables. HLMs were compared with the less suitable classical linear regression model, and bivariate and univariate HLMs with or without area as a covariate were compared in terms of their posterior predictive precision and accuracy. One of the main research questions was the model’s ability to predict the BMI of the child, which we assessed with various posterior predictive checks (PPC). The most suitable model was used to estimate growth parameters of 2-6 year old males and females in Vihti, Kirkkonummi and Tuusula. With the parameter estimates, we could compare growth of males and females, assess the differences of within-subject and between-subject variability on growth and examine correlation between height and weight development. Based on the work, we could conclude that the bivariate HLM constructed provided the most accurate and precise predictions especially for the BMI. The area covariates did not provide additional advantage to the models. Overall, Bayesian HLMs are a suitable tool for the register-based dataset of the work, and together with log-transformation of height and weight they can be used to model skewed and heteroschedastic longitudinal data. However, the modeling would ideally require more observations per individual than we had, and proper out-of-sample predictive evaluation would ensure that current models are not over-fitted with regards to the data. Nevertheless, the built models can already provide insight into contemporary Finnish childhood growth and to simulate and create predictions for the future BMI population distributions.

The current multidisciplinary interests on human intestinal microbiomes have stimulated large scale research initiatives, involving collection and processing of up to thousands of fecal samples within a single study. Hence, there is a need for high throughput protocols that are cost-efficient and validated for their performance to ensure that the relative abundance of different bacteria, the main outcome of microbiota studies, is not biased due to technical artefacts originating from sample processing. Infant’s microbiota colonization is one of the central research areas in human microbiome research because of the long-lasting and profound health implications of the pioneering microbes. This experimental study aimed to develop and validate a high throughput fecal sample collection and processing system for microbial DNA extraction operating in 96 well format. This newly developed method was used to extract DNA from 647 fecal samples collected from mother-infant pairs within a clinical study that will study the effect of antenatal antibiotic prophylaxis on infant’s gut microbiota development. A subset of 28 mother-infant pair samples (14 from each antibiotic and non-antibiotic groups) were selected to study the prevalence of a probiotic bacterium, Lactobacillus rhamnosus GG (LGG), among infants and their mothers longitudinally from birth to 3 months by using species-specific PCR amplification method targeting sortase C gene. In addition, the prevalence of L. rhamnosus GG in 3-month-old infants was compared between the above samples and those (n=30) collected in another clinical trial conducted ~10 years earlier. From extensive testing and validation, an efficient high throughput system for fecal sample collection and processing for extraction of microbial DNA in 96 well format was established. Tests were performed to validate the performance of a) fecal sample collection system b) commercial, readymade bead beating tubes for bacterial cell lysis and c) selfmade wash buffers as part of the automatic DNA purification system. Performance was evaluated based on the quality and quantity of the resultant DNA. We show that this new fecal processing system can yield high quality microbial DNA from 96 fecal samples within ~6 hrs. Based on the ratios of dominant gram-positive and gram-negative bacteria evaluated using PCRs and next generation sequencing, the new DNA extraction method resulted into similar microbiota composition than the previously validated manual DNA extraction method. However, the DNA yield per sample was markedly lower due to the lower input volume of the sample. Based on the sortase C gene PCR tests, the prevalence of LGG was similar (~60%) among 3-month-old children in both clinical studies conducted ~10 years apart, although false negatives among the recent samples due to the low amount of DNA cannot be excluded. Following the temporal pattern of colonization, we observed no evidence for the transfer of LGG at the time of birth from the mother to her child, instead the infants became positive for LGG typically between 1-3 weeks after birth. The carriage of LGG seemed to be dependent on their diet. During this project, we found out that the PCR method employed for detection of LGG was not fully specific for this strain, and hence a more specific qPCR assay was developed.

Non-communicable diseases such as cardiovascular diseases (CVDs) and erosive, unsustainable industrial fat-production methods pose two of the biggest threats to human health in great part of our planet. CVDs and obesity have been linked to diets high in fat and low in dietary fibre, pushing food manufacturers to adapt to more sustainable ingredients. For this reason, this research developed and researched about a new and sustainable plant-based oleogel intended to act as a substitute for saturated and hydrogenated fats. Its characterization was conducted through several techniques, including optical and field emission electron scanning microscopy, differential scanning calorimetry, Fourier transmission infrared spectroscopy, and synchrotron X-ray powder diffraction. The results showed that the build-up of the formation of the new oleogel was possible, while ensuring that both processing requirements and ingredients are readily available at food manufacturing plants, globally. These findings pose a great opportunity for plant-based fat-replacement formulations, through a sustainable approach. Considering previous studies, this novel system could potentially help in reducing the burden of obesity and CVDs, turning it into a functional food component. Further research on food applications and digestibility models could give more insight on the future applications of this fat-replacement system.