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In software configuration management, branching is a common practice, which can enable efficient parallel development between developers and teams. However, the developers might not be aware of the different branching practice options and how to exactly formulate a branching strategy. This could lead to an opposite effect towards productivity, and other issues as well. The focus of this thesis is in what branching practices are considered as beneficial, what affects their usability, what risks are involved, and how to plan these practices in a structured manner. There are plenty of branching practices presented in the literature, which can either complement each other or be completely incompatible. A lot of the practices' beneficiality depends on the surrounding context, such as the tools in use and project characteristics. The most relevant risk to branching is merge conflicts, but there are other risks as well. The approaches for planning a branching strategy, however, are found to be too narrow in the reviewed literature. Thus, Branching Strategy Formulation and Analysis Method (BSFAM) is proposed to help teams and organizations plan their branching strategy in a structured manner. Additionally, the issues of branching are explored in the context of an organization that has multiple concurrent projects ongoing for a single product. Information on this is gathered through a survey, semi-structured interviews, and available documentation. The issues that were found can be attributed to a lack of proper base strategy, difficulties in coordination and awareness, and test automation management in relation to branching. The proposed method is then applied in that same context in order to provide solutions to the organization's issues, and to provide an example case. BSFAM will be taken into use in upcoming projects in the organization, and it will be improved if necessary. If the proposed method is to be adopted more widely and its resulting information published, it could provide further research towards how different branching practices fit in different contexts. Additionally, it could help in new, generally better, branching practices to emerge.

In this study, a quality assessment method based on sampling of primary laser inventory units (microsegments) was analysed. The accuracy of a laser inventory carried out in Kuhmo was analysed as a case study. Field sample plots were measured on the sampled microsegments in the Kuhmo inventory area. Two main questions were considered. Did the ALS based inventory meet the accuracy requirements set for the provider and how should a reliable, cost-efficient and independent quality assessment be undertaken. The agreement between control measurement and ALS based inventory was analysed in four ways: 1) The root mean squared errors (RMSEs) and bias were calculated. 2) Scatter plots with 95% confidence intervals were plotted and the placing of identity lines was checked. 3) Bland-Altman plots were drawn so that the mean difference of attributes between the control method and ALS-method was calculated and plotted against average value of attributes. 4) The tolerance limits were defined and combined with Bland-Altman plots. The RMSE values were compared to a reference study from which the accuracy requirements had been set to the service provider. The accuracy requirements in Kuhmo were achieved, however comparison of RMSE values proved to be difficult. Field control measurements are costly and time-consuming, but they are considered to be robust. However, control measurements might include errors, which are difficult to take into account. Using the Bland-Altman plots none of the compared methods are considered to be completely exact, so this offers a fair way to interpret results of assessment. The tolerance limits to be set on order combined with Bland-Altman plots were suggested to be taken in practise. In addition, bias should be calculated for total area. Some other approaches for quality control were briefly examined. No method was found to fulfil all the required demands of statistical reliability, cost-efficiency, time efficiency, simplicity and speed of implementation. Some benefits and shortcomings of the studied methods were discussed.

ALICE (A Large Ion Collider Experiment) is an experiment at CERN (European Organization for Nuclear Research), where a heavy-ion detector is dedicated to exploit the unique physics potential of nucleus-nucleus interactions at LHC (Large Hadron Collider) energies. In a part of that project, 716 so-called type V4 modules were assembles in Detector Laboratory of Helsinki Institute of Physics during the years 2004 - 2006. Altogether over a million detector strips has made this project the most massive particle detector project in the science history of Finland. One ALICE SSD module consists of a double-sided silicon sensor, two hybrids containing 12 HAL25 front end readout chips and some passive components, such has resistors and capacitors. The components are connected together by TAB (Tape Automated Bonding) microcables. The components of the modules were tested in every assembly phase with comparable electrical tests to ensure the reliable functioning of the detectors and to plot the possible problems. The components were accepted or rejected by the limits confirmed by ALICE collaboration. This study is concentrating on the test results of framed chips, hybrids and modules. The total yield of the framed chips is 90.8%, hybrids 96.1% and modules 86.2%. The individual test results have been investigated in the light of the known error sources that appeared during the project. After solving the problems appearing during the learning-curve of the project, the material problems, such as defected chip cables and sensors, seemed to induce the most of the assembly rejections. The problems were typically seen in tests as too many individual channel failures. Instead, the bonding failures rarely caused the rejections of any component. One sensor type among three different sensor manufacturers has proven to have lower quality than the others. The sensors of this manufacturer are very noisy and their depletion voltage are usually outside of the specification given to the manufacturers. Reaching 95% assembling yield during the module production demonstrates that the assembly process has been highly successful.

“Excessive delays in the delivery of justice are equal to the denial of justice”. This is a sentence that has repeatedly appeared in different reports, research papers, comments and opinions circling the UN internal justice system. This article attempts to seek answers to the question whether it is possible to assess the quality of justice of the UN internal justice system in different ways established in national and supra-national organizations.

Mobile users surpassing desktop users have tempted mobile network operators to deploy traffic shaping policies to utilize the resources efficiently. These policies have significantly lowered the quality of service of applications. Present systems can accurately detect the traffic discrimination of different application protocols for instance BitTorrent in context to HTTP protocol and extract the quality of the service statistically by comparing the data. This thesis proposes a method that tries to understand the system performance and applications behavior along with the network performance in requesting and delivering the desired quality of service. We devised a framework which tests an MNO (Mobile Network Operator) and their policies on the 4G Network regarding the Type of Service flags in the IP Header. We investigate whether the network path allows applications like Skype, WhatsApp, Facebook Messenger and Viber to set the Type of Service (DSCP Class) in their IP Header. We implemented the framework as an Android application which sets the DSCP Class in the IP Header for each respective application’s data. Our results show that major mobile network operators in Finland do not allow the applications to set DSCP classes in their IP Header for the better quality of service.

The human brain is divided into left and right hemisphere, and there are functional differences between the hemispheres. A hemispheric difference is called the lateralization of the brain function, and the degree of lateralization is described by the laterality index. The most investigated domain of the lateralized brain functions is language, which is a left hemisphere dominant function in the majority of the population. Functional magnetic resonance imaging provides a noninvasive method for studying the brain functions indirectly through the bloodoxygenation-level-dependent effect. The language-related functional magnetic resonance imaging can be used in the localization of the Broca’s speech area and determination of the dominant hemisphere in epileptic patients. The purpose of this thesis is to assess a method for calculating the laterality index from functional magnetic resonance imaging data. The data is acquired during three language task paradigms with five subjects and analyzed statistically. The methods used for the laterality index calculations are reviewed, and a new calculation method is presented. Result tables of laterality indices and hemispheric dominances per used regions of interest are generated. The presented laterality index calculation method successfully determined the speech laterality of three subjects out of five as a left hemispheric dominance. The language laterality of two subjects was not successful due to corrupted functional data and contradicted results between different paradigms. The major source of error is the subject’s head motion during the functional imaging. Together with the information about the head motion’s extent, the generated table could provide relevant extra information to epileptic patients’ functional magnetic resonance imaging data and could serve for clinical purposes in the future.

Human induced pluripotent stem cells (hiPSC) can be propagated in a long-term culture and further differentiated into many cell types, including cardiomyocytes (CM) and endothelial cells (EC). Human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CM) are promising tools in cardiac research, since they retain the original genotype of the individual donor and thus enable the use of patient- and disease specific cells. Crucial for the optimal use of hiPSC-CMs in experiments are methods for assessing cardiomyocyte phenotype. Contraction is a prominent feature for CMs, and it is essential that contraction can be quantified accurately. Reliable quantification is relevant when hiPSC-CMs are used for studying disease phenotypes, cardiac safety pharmacology, genotype-phenotype correlations, cardiac disease mechanisms and cardiac function over time. In this thesis project, contractile behavior of hiPSC-CMs was analyzed using video microscopy and online tool MUSCLEMOTION. Contraction parameters were obtained from hiPSC-CMs derived from patients with hypoplastic left heart syndrome (HLHS) and healthy controls on multiple timepoints during differentiation. In addition, contraction was analyzed in iPSC-CMs cocultured with induced pluripotent stem cell derived endothelial cells (iPSC-ECs), since it has been suggested that ECs can promote morphological and functional maturation of CMs in culture. Contraction duration (CD), time to peak (TTP), relaxation time (RT) and contraction amplitude (CA) was compared between different timepoints as well as between CMs cocultured with ECs and CMs cultured alone. Compared to control cell lines, HLHS patient hiPSC-CMs exhibited longer CD, TTP and RT as well as higher CA values. This difference was present in most of the timepoints, suggesting slower contractile kinetics in HLHS patient iPSC-CMs compared to control iPSC-CMs. Significant changes were also observed in contraction parameters when comparing hiPSC-CMs in coculture and monoculture. Contraction parameters of coculture iPSC-CMs changed in a relatively consistent manner over time, increasing or decreasing throughout the monitoring period whereas in hiPSC-CM monoculture there was more variation between timepoints. This project and results support the use of modern methods in detailed functional characterization of hiPSC-derived cells. In addition, it highlights the potential of coculture in disease modeling and the fact that hiPSC-CMs express variation in phenotypes. However, experiments should be repeated, and additional methods should be used in order to further validate the results and conclusions.

Measuring risk is mandatory in every form of responsible asset management; be it mitigating losses or maximizing performance, the level of risk dictates the magnitude of the effect of the strategy the asset manager has chosen to execute. Many common risk measures rely on simple statistics computed from historic data. In this thesis, we present a more dynamic risk measure explicitly aimed at the commodity futures market. The basis of our risk measure is built on a stochastic model of the commodity spot price, namely the Schwartz two-factor model. The model is essentially determined by a system of stochastic differential equations, where the spot price and the convenience yield of the commodity are modelled separately. The spot price is modelled as a Geometric Brownian Motion with a correction factor (the convenience yield) applied to the drift of the process, whereas the convenience yield is modelled as an Ornstein-Uhlenbeck process. Within this framework, we show that the price of a commodity futures contract has a closed form solution. The pricing of futures contracts works as a coupling between the unobservable spot price and the observable futures contract price, rendering model fitting and filtering techniques applicable to our theoretic model. The parameter fitting of the system parameters of our model is done by utilizing the prediction error decomposition algorithm. The core of the algorithm is actually obtained from a by-product of a filtering algorithm called Kalman filter; the Kalman filter enables the extraction of the likelihood of a single parameter set. By subjecting the likelihood extraction process to numerical optimization, the optimal parameter set is acquired, given that the process converges. Once we have attained the optimal parameter sets for all of the commodity futures included in the portfolio, we are ready to perform the risk measurement procedure. The first phase of the process is to generate multiple future trajectories of the commodity spot prices and convenience yields. The trajectories are then subjected to the trading algorithm, generating a distribution of the returns for every commodity. Finally, the distributions are aggregated, resulting in a returns distribution on a portfolio level for a given target time frame. We show that the properties of this distribution can be used as an indicator for possible anomalies in the returns within the given time frame.

Clean snow has the highest albedo of any natural surface, making snow-covered glaciers an important component of the Earth´s energy balance. However, the presence of light absorbing impurities such as mineral dust on glacier surfaces alters their reflective properties leading to a reduction in albedo, consequently increasing absorption of incoming solar radiation which further impacts the glacier surface mass balance (SMB). Icelandic glaciers portray a high annual and inter-annual variability in SMB due to climate variability but deposition of mineral dust originating from glaciofluvial dust hotspots can have large impacts on summer ablation. The frequency of dust storms and deposition is then controlled by high velocity winds and prolonged dry periods. Additionally, Icelandic mineral dust contains high amount of iron and iron oxides which makes it extremely light absorbing. An extensive dust event occurred over the southwest outlets of Vatnajökull ice cap during early July of 2022 causing surface darkening. To investigate the impact of the dust event on the melt season SMB, this study used automatic weather station (AWS) data from three different sites on Tungnaárjökull glacier, a SW-outlet of Vatnajökull ice cap. Daily melt was estimated with a simple snow-melt model and AWS data. To quantify the overall impact of dust on the melt rates, albedo from 2015 melt season for the three AWS sites was used to simulate the surface albedo for a dust-free surface during the 2022 melt season. Essentially, the dust event caused melt enhancement of almost 1.5 m water equivalent (mwe) above 1000 m elevation. As Icelandic glaciers exhibit large spatial variations over the melt season, the SMB sensitivity to dust deposition varied with elevation, being strongest at the uppermost site. Additionally, the sensitivity to timing of dust event were investigated which demonstrated that earlier occurrence increases the melt while later occurrence reduces the melt, compared to the July event. The results of this study reveal the impact of positive radiative forcing on SMB of Tungn

Piperine represents the major plant alkaloid encountered in various Piperaceae species and has received in recent years considerable attention because of its broad range of favorable biological and pharmacological activities, including antioxidant, immunostimulant, bioavailability-enhancing and anti-carcinogenic properties. The literature part of this thesis gives a selective overview of advanced methods for the quantitative analysis of piperine in plant-base materials, and various approaches employed for instrumental analysis, including spectroscopic, chromatographic, and electrochemical techniques. An effort was made to evaluate the potential of the reported methods based on the analytical figures of merit, such as total sample throughput capacity, analytical range, precision, accuracy, limit of detection and limit of quantification. The objective of the experimental part of the thesis focused on the development of a convenient, robust, simple, efficient and reliable method to quantify piperine in pepper fruits. The analytical method established in this thesis involves liberation of piperine by continuous liquid extraction of ground pepper fruits with methanol, and cleanup of the crude extracts with reversed phase solid phase extraction. Analyte quantitation was accomplished using gradient reversed phase High Performance Liquid Chromatography with mass spectrometric detection, using Electrospray Ionization-Ion Trap Mass Spectrometry. To enable reliable internal standardization, deuterium labelled piperine surrogate (piperine-D10) was synthesized from piperine in three steps in a reasonable overall yield (65 %) and standard-level purity (99.7 %). It may be worth mentioning that the commercial market value of the amount of piperine-D10 synthesized in-house exceeds 167,400 euros. One of the major challenges encountered during the development and optimization of the analytical method was the extreme photosensitivity of piperine and piperine-D10, both suffering in solution extensive photoisomerization upon exposure to ambient light within matter of minutes. This issue was addressed by carrying out all tasks associated with synthesis, sample preparation and analytical measurements under dark conditions. For the preparation of calibrators, a fully automated procedure was developed, being controlled by custom-written injector programs and executed in the light-protected sample compartment of a conventional autosampler module. In terms of merits, the developed analytical method offers good sample throughput capacity (run time 20 min, retention time 8.2 min), excellent selectivity and high sensitivity (Limit of Detection= 0.012 ppm, Limit of Quantification= 0.2 ppm). The method is applicable over a linear range of 0.4 to 20 ng of injected mass (r2= 0.999). The stability of standards and fully processed samples was found to be excellent, with less than 5% of variations in concentrations occurring after a 3-week (calibrators) or 4-month (samples) storage at 4 °C and 23 °C respectively, under dark conditions. Intra-day repeatability were better than 2.95 %. Preliminary validation data also suggest satisfactory inter-operator reproducibility. To test the applicability of the developed LC-MS method, it was employed to quantify piperine in a set of 15 pepper fruit samples, including black, white, red and green varieties of round and long peppers, purchased from local markets and retailers. The piperine contents obtained were in the range of 17.28 to 56.25 mg/g (piperine/minced sample) and generally in good agreement with the values reported in the scientific literature. It is justified to assume that the developed analytical method may directly be applicable to the quantitation of related pepper alkaloids in herbal commodities, and after some modifications in the sample preparation strategy, also for the monitoring of piperine in biological fluids, such as serum and urine.