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Lithium-ion batteries (LIBs) are used to power portable electronic devices and electric vehicles (EVs). Cobalt has been an essential element on popular cathode active materials of LIBs since the commercialization of LiCoO2 (LCO) by Sony in 1991. However, most cobalt reserves and processing facilities are in Democratic Republic of Congo (DRC) and China. This creates geopolitical risks and restricts supply expansion. On top of that, child labour is used to mine cobalt in DRC. Consequently, cobalt free and low-cobalt materials should be and are developed and used for commercial applications. One of the common cobalt free materials used today is lithium iron phosphate, also known as LiFePO4 (LFP). LFP was identified as a cathode material for LIBs by Padhi, Nanjundaswamy, and Goodenough in 1997. Main advantages of LFP are its flat voltage profile, low cost, abundant material supply, environmental friendliness (nontoxic and cobalt free), and thermal stability. The downsides include relatively low theoretical capacity, low energy density, low electronic conductivity, and low ionic diffusivity. This study focuses on synthesis of modified LFP and its electrochemical properties. Common and novel synthesis methods are reviewed shortly. Especially, performance increasing modifications are reviewed. These include coating, control of particle size and particle morphology, and doping in which ions are used to replace atoms in LFP. Effects of the modifications are discussed through the paper with most time spent on doping and comparison of the effects induced by doping with different elements. In the end the dopants are ranked according to their effects on performance, price, and sustainability of a battery. To understand the modifications and their effect on electrochemical performance the structure of the material must be studied and understood. Because of this a chapter to crystallography and structure of LFP is included. Similarly, some basic information about common electrochemical characterization techniques is included to help the reader understand the plots and values produced by them. These include cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), electrode setups, and terminology.

In this paper, common structural analysis methods of activated carbon anodes for lithium-ion batteries are reviewed shortly. These include transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, and nitrogen adsorption-desorption. The key parameters extracted with the analysis methods are collected into a table. Basics about batteries and chemical activation of carbon are also discussed.

Objectives/Aims: This cross-sectional study aimed to examine oral health and oral health-related habits among prisoners at the Pelso Prison in Finland. Materials and Methods: Participants in this cross-sectional study comprises 100 inmates. A calibrated dentist recorded the decayed, filled and missed teeth as well as periodontal status (bleeding-on-probing, pocket probing and Community Periodontal Index) among the participants (n=100). Fifty inmates were also interviewed for marital status, education and oral health-related habits. The Ethical Committee of the Northern Ostrobothnia Hospital District and the Criminal Sanctions Agency approved the study protocol. Results: The participants were on average 35 years old and had 5 (s.d. 5.1) decayed teeth in need of restorative treatment, whereas DMFT was 17 (s.d. 8.9). Half of the study population had periodontal disease in need of professional treatment. Almost all reported brushing their teeth daily. Two-third ate sweets, one-third drank fizzy drinks and majority smoked every day. Almost two-third had used illicit drugs at some point of their lives. Almost all drunk alcohol once a week or more often. No statistically significant associations were discovered between dental treatment need and explanatory factors. Discussion: Prisoners appear to be a homogenous group with poor oral health and harmful health behaviours.

This thesis studied effort estimation in software development, focusing on task level estimation that is done in Scrum teams. The thesis was done at Nokia Networks and the motivation for this topic came from the poor estimation accuracy that has been found to be present in software development. The aim of this thesis was to provide an overview of what is the current state of the art in effort estimation, survey the current practices present in Scrum teams working on LTE L2 software component at Nokia Networks Oulu, and then present suggestions for improvement based on the findings. On the basis of the literature review, three main categories of effort estimation methods were found: expert estimation, algorithmic models and machine learning. Universally there did not seem to be a single best method, but instead the differences come from the context of use. Algorithmic models and machine learning require data sets, whereas expert estimation methods rely on previous experiences and intuition of the experts. While model based methods have received a lot of research attention, the industry has largely relied on expert estimation. The current state of effort estimation at Nokia Networks was studied by conducting a survey. This survey was built based on previous survey studies that were found by conducting a systematic literature review. The questions found in the previous studies were formulated into a questionnaire, which was then used to survey the current effort estimation practices present in the participating teams. 41 people out of 100 in the participating teams participated in the survey. Survey results showed that like much of the software industry, the teams in LTE L2 relied on expert estimation methods. Most respondents had encountered overruns in the last sprint and the most often provided reason was that testing related effort estimation was hard. Forgotten subtasks were encountered frequently and requirements were found to be both unclear and to change often. Very few had had any training on effort estimation. There were no common practices for effort data collection and as such, it was mostly not done. By analyzing the survey results and reflecting them on the previous research, five suggestions for improvements were found. These were training in effort estimation, improving the information that is used during effort estimation by collaborating with specification personnel, improving testing related effort estimation by splitting acceptance testing into their own tasks, collecting and using effort data, and using Planning Poker as an effort estimation method, as it fit the context of estimation present in the teams. The study shed light on how effort estimation is done in software industry. Another contribution was the improvement suggestions, which could potentially improve the situation in the teams that participated in the survey. A third contribution was the questionnaire built during this study, as it could potentially be used to survey the current state of effort estimation in also other contexts.

Radio link adaptation, multiple antenna techniques, relaying methods and dynamic radio resource assignment are among the key methods used to improve the performance of wireless communication networks. Opportunistic resource block (RB) allocation in downlink orthogonal frequency division multiple access (OFDMA) with limited feedback is considered. The spectral efficiency analysis of multiuser OFDMA with imperfect feedback path, multiple antenna methods and relaying methods is a particular focus. The analysis is derived for best-M feedback methods and for a RB-wise signal-to-noise ratio (SNR) quantization based feedback strategy. Practical resource fair round robin (RR) allocation is assumed at the RB assignment, i.e., each user gets the same portion of the available RBs. The fading of each RB is modelled to be independent and identically distributed (IID). This assumption enabled a communication theoretic approach for the performance evaluation of OFDMA systems The event probabilities related to the considered OFDMA systems are presented so that the feedback bit error probability (BEP) is a parameter in the expressions. The performance expressions are derived for the BEP in the case of binary phase-shift keying (BPSK) modulation and single antenna methods. Asymptotic BEP behavior is considered for the best-M feedback methods when the mean SNR tends to infinity. The system outage capacity and the average system spectral efficiency are investigated in the case of multiple antenna schemes. Antenna selection and space-time block coding (STBC) are considered in multiple antenna schemes when each RB is allocated exclusively to a single user. Simple OFDMA-spatial division multiple access (SDMA) schemes are also analyzed when zero forcing (ZF) detection is assumed at the receiver. Relay enhanced dynamic OFDMA with single and multiple antennas at each end is considered for fixed infrastructure amplify-and-forward (AF) relaying methods. The average spectral efficiency has been derived for the best-M and RB-wise one bit feedback schemes, antenna selection and STBC methods. The best choice for a combination of multiple antenna scheme and feedback strategy depends on several system parameters. The proposed analytical tools enable easy evaluation of the performance of the investigated schemes with different system parameters. The fundamental properties of the combinations of feedback and multiple antenna schemes are extensively studied through numerical examples. The results also demonstrate that the analytical results with idealized IID fading assumption are close to those obtained via simulations in a practical frequency selective channel when RBs are selected properly. Dynamic RB allocation is attractive for practical OFDMA systems since significant performance gain over random allocation can be achieved with a practical allocation principle, very low feedback overhead and an imperfect feedback channel.

Secretory carbonic anhydrase isoenzyme VI (CA VI) catalyses the reversible hydration of carbon dioxide (CO2 + H2O ↔ HCO3- + H+). Low concentrations of salivary CA VI are associated with high decayed, missing or filled teeth (DMFT) index scores and a high incidence of acid injury in the upper gastrointestinal tract plus lowered taste and smell perception. Two mechanisms of action for CA VI have been proposed: acid neutralisation and growth factor function. In the present study the distribution and catalytic properties of CA VI have been examined in order to further clarify its mechanisms of action and biological significance. CA VI was found to be present and secreted by the alveolar epithelium of the mammary gland, serous acinar cells of lingual von Ebner’s glands, serous demilune cells of posterior lingual mucous glands and serous cells of submucosal tracheobronchial glands. CA VI was also found in the serous cells in the tracheobronchial mucosal epithelium, taste pore, taste bud, base of the tracheobronchial cilia, bronchiolar Clara cells and enamel pellicle. An immunofluorometric assay showed that the mean concentration of CA VI in colostral milk was eight times higher than that in mature milk (35 mg/l vs. 4.5 mg/l). Stopped-flow spectroscopy measurements revealed that the dehydration activity of CA VI is moderate (maximum kcat = 3.0 × 105 · s-1). The finding that CA VI is a potent catalyst of acid neutralisation emphasizes the possible role of the pellicle bound CA VI in local neutralisation of the acidic metabolic products of dental biofilm. The function of CA VI in von Ebner’s glands’ saliva is likely taste stimuli modification via CA activity although other functions may exist. Its role in milk or respiratory tract mucus remains open, however, as these secretions do not have significant acid predispositions that would need enzymatic catalysis for removal.

The successful ‘project definition’ phase is the corner stone in realising satisfying end products. In the building and construction domain, this phase is particularly important, yet it is often rushed and poorly conducted. Jumping straight into technical solutions is the modus operandi. Typically, the architect’s first proposal for a building layout acts as the baseline for the decision-making throughout the entire project. Inclusion of the end user objectives usually happens (unsatisfactorily) by simply asking for comments on the proposed technical solutions. This can easily lead to a loss of value and can cause problems during the use of the building, and lead to disputes during the construction. It is widely recognised that human and organisational questions need more attention than technical solutions in the early phases of the process. The performance approach has been presented as one potential catalyst for positive change in this area. The performance approach is concerned with what the building is required to do, not with describing the technical solutions i.e. how it is constructed. A key driver for the performance approach implementation in Finland has been a software tool called EcoProP. Its next generation version, PRISM, stands for ‘Intelligent Systematic Performance Requirements Management’ and is currently being translated and revised for application in Australia and other countries. In this paper, current problems in the project definition phase are presented. The requirements management and performance approach are introduced, and the barriers to implementation are discussed. The use of EcoProP on projects in Finland is presented, and in conclusion, the use of PRISM for performance requirements management in various countries is discussed.

OBJECTIVE--To estimate the usefulness of serum concentrations of the complex of trypsin 2 and alpha 1 antitrypsin in diagnosing and assessing the severity of acute pancreatitis in comparison with serum C reactive protein, amylase, and trypsinogen 2 concentrations (reference markers). DESIGN--Markers were measured in consecutive patients admitted with acute abdominal pain that was either due to pancreatitis or to other disease unrelated to the pancreas (controls). SETTING--Department of surgery of a teaching hospital in Helsinki. SUBJECTS--110 patients with acute pancreatitis and 66 with acute abdominal diseases of extrapancreatic origin. On the basis of the clinical course, acute pancreatitis was classified as mild (82 patients) or severe (28 patients). MAIN OUTCOME MEASURES--Clinical diagnosis of acute pancreatitis and severity of the disease. RESULTS--At admission all patients with acute pancreatitis had clearly raised concentrations of trypsin 2-alpha 1 antitrypsin complex (32 micrograms/l), whereas only three of the controls had such values. Of the markers studied, trypsin 2-alpha 1 antitrypsin complex had the largest area under the receiver operating curve, both in differentiating acute pancreatitis from extrapancreatic disease and in differentiating mild from severe disease. CONCLUSIONS--Of the markers studied, trypsin 2-alpha 1 antitrypsin complex was the most accurate in differentiating between acute pancreatitis and extrapancreatic disease and in predicting a severe course for acute pancreatitis.