Vascular Function in Chronic Kidney Disease and in Renovascular Disease

Cardiovascular mortality is 15 to 30 times higher in patients with chronic kidney disease than in the age-adjusted general population. Even minor renal dysfunction predicts cardiovascular events and death in the general population. In patients with atherosclerotic renovascular disease the annual cardiovascular event and death rate is even higher. The abnormalities in coronary and peripheral artery function in the different stages of chronic kidney disease and in renovascular disease are still poorly understood, nor have the cardiac effects of renal artery revascularization been well characterized, although considered to be beneficial. This study was conducted to characterize myocardial perfusion and peripheral endothelial function in patients with chronic kidney disease and in patients with atherosclerotic renovascular disease. Myocardial perfusion was measured with positron emission tomography (PET) and peripheral endothelial function with brachial artery flow-mediated dilatation. It has been suggested that the poor renal outcomes after the renal artery revascularization could be due to damage in the stenotic kidney parenchyma; especially the reduction in the microvascular density, changes mainly evident at the cortical level which controls almost 80% of the total renal blood flow. This study was also performed to measure the effect of renal artery stenosis revascularization on renal perfusion in patients with renovascular disease. In order to do that a PET-based method for quantification of renal perfusion was developed. The coronary flow reserve of patients with chronic kidney disease was similar to the coronary flow reserve of healthy controls. In renovascular disease the coronary flow reserve was, however, markedly reduced. Flow-mediated dilatation of brachial artery was decreased in patients with chronic kidney disease compared to healthy controls, and even more so in patients with renovascular disease. After renal artery stenosis revascularization, coronary vascular function and renal perfusion did not improve in patients with atherosclerotic renovascular disease, but in patients with bilateral renal artery stenosis, flow-mediated dilatation improved. Chronic kidney disease does not significantly affect coronary vascular function. On the contrary, coronary vascular function was severely deteriorated in patients with atherosclerotic renovascular disease, possibly because of diffuse coronary artery disease and/or diffuse microvascular disease. The peripheral endothelial function was disturbed in patients with chronic kidney disease and even more so in patient with atherosclerotic renovascular disease. Renal artery stenosis dilatation does not seem to offer any benefits over medical treatment in patients with renovascular disease, since revascularization does not improve coronary vascular function or renal perfusion.

Antimicrobial Resistance in Campylobacter jejuni and Campylobacter coli

Antimicrobial Resistance in Campylobacter jejuni and Campylobacter coli Campylobacters are a common cause of bacterial gastroenteritis worldwide, with Campylobacter jejuni and C. coli being the most common species isolated in human infections. If antimicrobial treatment is required, the drugs of choice at the moment are the macrolides and fluoroquinolones. In this thesis, the in vitro resistance profiles of the C. jejuni and C. coli strains were evaluated with emphasis on multidrug resistance. The aim was also to evaluate the different resistance mechanisms against the macrolides. Further, the disk diffusion method was compared to agar dilution method and its repeatability was evaluated, since it has been widely used for the susceptibility testing of campylobacters. The results of the present study showed that resistance to the fluoroquinolones is common in strains isolated from Finnish patients, but resistance to the macrolides is still rare. Multidrug resistance was associated with resistance to both ciprofloxacin and erythromycin. Among the available per oral drugs, least resistance was observed to coamoxiclav There was no resistance to the carbapenems. Sitafloxacin and tigecycline were in vitro highly effective towards Campylobacter species. A point mutation A2059G of the 23S rRNA gene was the main mechanism behind the macrolide resistance, whereas the efflux pumps did not seem to play an important role when a strain had A2059G mutation. A five amino acids insertion, which has not been described previously, in the ribosomal protein L22 of one highly-resistant C. jejuni strain without mutation in the 23S rRNA gene was also detected. Concerning the disk diffusion method, there was variation in the repeatability In conclusion, macrolides still appear to be the first-choice alternative for suspected Campylobacter enteritis. The in vitro susceptibilities found suggest that co-amoxiclav might be a candidate for clinical trials on campylobacteriosis, but in life-threatening situations, a carbapenem may be the drug of choice. More studies are needed on whether the disk diffusion test method could be improved or whether all susceptibilities of campylobacters should be done using a MIC based method.

Kestomagneettikoneen roottorin väsymisanalyysi

Työn tavoitteena oli luoda työkalu kestomagneettikoneiden roottoreiden väsymisen analysointia varten. Työkalu toteutettiin siten, että siihen voidaan liittää oikeasta koneesta mitattu kuormitusdata, sekä tarvittavat materiaalitiedot. Kuormitusdata muunnetaan työkalussa jännityshistoriaksi käyttämällä elementtimenetelmän avulla laskettavaa skaalauskerrointa. Kestoiän laskemiseen analyysityökalu käyttää jännitykseen perustuvaa menetelmää sekä rainflowmenetelmää ja Palmgren-Minerin kumulatiivista vauriosääntöä. Lisäksi työkalu tekee tutkittavalle tapaukselle Smithin väsymislujuuspiirroksen. Edellä mainittujen menetelmien lisäksi työn teoriaosassa esiteltiin väsymisanalyysimenetelmistä myös paikalliseen venymään perustuva menetelmä sekä murtumismekaniikka. Nämä menetelmät jäivät monimutkaisuutensa vuoksi toteuttamatta työkalussa. Väsymisanalyysityökalulla laskettiin kestoiät kahdelle esimerkkitapaukselle. Kummassakin tapauksessa saatiin tulokseksi ääretön kestoikä, mutta aksiaalivuokoneen roottorin dynaaminen varmuus oli pieni. Vaikka tulokset vaikuttavat järkeviltä, ne olisi vielä hyvä verifioida esimerkiksi kaupallisen ohjelmiston avulla täyden varmuuden saamiseksi.

Synthesis of percarboxylic acids in microreactor

Percarboxylic acids are commonly used as disinfection and bleaching agents in textile, paper, and fine chemical industries. All of these applications are based on the oxidative potential of these compounds. In spite of high interest in these chemicals, they are unstable and explosive chemicals, which increase the risk of synthesis processes and transportation. Therefore, the safety criteria in the production process should be considered. Microreactors represent a technology that efficiently utilizes safety advantages resulting from small scale. Therefore, microreactor technology was used in the synthesis of peracetic acid and performic acid. These percarboxylic acids were produced at different temperatures, residence times and catalyst i.e. sulfuric acid concentrations. Both synthesis reactions seemed to be rather fast because with performic acid equilibrium was reached in 4 min at 313 K and with peracetic acid in 10 min at 343 K. In addition, the experimental results were used to study the kinetics of the formation of performic acid and peracetic acid. The advantages of the microreactors in this study were the efficient temperature control even in very exothermic reaction and good mixing due to the short diffusion distances. Therefore, reaction rates were determined with high accuracy. Three different models were considered in order to estimate the kinetic parameters such as reaction rate constants and activation energies. From these three models, the laminar flow model with radial velocity distribution gave most precise parameters. However, sulfuric acid creates many drawbacks in this synthesis process. Therefore, a ´´greener´´ way to use heterogeneous catalyst in the synthesis of performic acid in microreactor was studied. The cation exchange resin, Dowex 50 Wx8, presented very high activity and a long life time in this reaction. In the presence of this catalyst, the equilibrium was reached in 120 second at 313 K which indicates a rather fast reaction. In addition, the safety advantages of microreactors were investigated in this study. Four different conventional methods were used. Production of peracetic acid was used as a test case, and the safety of one conventional batch process was compared with an on-site continuous microprocess. It was found that the conventional methods for the analysis of process safety might not be reliable and adequate for radically novel technology, such as microreactors. This is understandable because the conventional methods are partly based on experience, which is very limited in connection with totally novel technology. Therefore, one checklist-based method was developed to study the safety of intensified and novel processes at the early stage of process development. The checklist was formulated using the concept of layers of protection for a chemical process. The traditional and three intensified processes of hydrogen peroxide synthesis were selected as test cases. With these real cases, it was shown that several positive and negative effects on safety can be detected in process intensification. The general claim that safety is always improved by process intensification was questioned.

A cyber security architecture for military networks using a cognitive network approach

Cyber security is one of the main topics that are discussed around the world today. The threat is real, and it is unlikely to diminish. People, business, governments, and even armed forces are networked in a way or another. Thus, the cyber threat is also facing military networking. On the other hand, the concept of Network Centric Warfare sets high requirements for military tactical data communications and security. A challenging networking environment and cyber threats force us to consider new approaches to build security on the military communication systems. The purpose of this thesis is to develop a cyber security architecture for military networks, and to evaluate the designed architecture. The architecture is described as a technical functionality. As a new approach, the thesis introduces Cognitive Networks (CN) which are a theoretical concept to build more intelligent, dynamic and even secure communication networks. The cognitive networks are capable of observe the networking environment, make decisions for optimal performance and adapt its system parameter according to the decisions. As a result, the thesis presents a five-layer cyber security architecture that consists of security elements controlled by a cognitive process. The proposed architecture includes the infrastructure, services and application layers that are managed and controlled by the cognitive and management layers. The architecture defines the tasks of the security elements at a functional level without introducing any new protocols or algorithms. For evaluating two separated method were used. The first method is based on the SABSA framework that uses a layered approach to analyze overall security of an organization. The second method was a scenario based method in which a risk severity level is calculated. The evaluation results show that the proposed architecture fulfills the security requirements at least at a high level. However, the evaluation of the proposed architecture proved to be very challenging. Thus, the evaluation results must be considered very critically. The thesis proves the cognitive networks are a promising approach, and they provide lots of benefits when designing a cyber security architecture for the tactical military networks. However, many implementation problems exist, and several details must be considered and studied during the future work.

Validation and Selection of Transportation Cost Drivers with Advanced Methods

In today's logistics environment, there is a tremendous need for accurate cost information and cost allocation. Companies searching for the proper solution often come across with activity-based costing (ABC) or one of its variations which utilizes cost drivers to allocate the costs of activities to cost objects. In order to allocate the costs accurately and reliably, the selection of appropriate cost drivers is essential in order to get the benefits of the costing system. The purpose of this study is to validate the transportation cost drivers of a Finnish wholesaler company and ultimately select the best possible driver alternatives for the company. The use of cost driver combinations as an alternative is also studied. The study is conducted as a part of case company's applied ABC-project using the statistical research as the main research method supported by a theoretical, literature based method. The main research tools featured in the study include simple and multiple regression analyses, which together with the literature and observations based practicality analysis forms the basis for the advanced methods. The results suggest that the most appropriate cost driver alternatives are the delivery drops and internal delivery weight. The possibility of using cost driver combinations is not suggested as their use doesn't provide substantially better results while increasing the measurement costs, complexity and load of use at the same time. The use of internal freight cost drivers is also questionable as the results indicate weakening trend in the cost allocation capabilities towards the end of the period. Therefore more research towards internal freight cost drivers should be conducted before taking them in use.

Novel Cellular Luminescence Probes for Immunological and Toxicological Assessments

Escherichia coli K-12 (pEGFPluxABCDEAmp) (E. coli-lux), constitutively emitting bioluminescence (BL), was constructed and its BL emitting properties tested in different growth and killing conditions. The BL emission directly correlated with the number of viable E. coli-lux cells, and when subjected to the antimicrobial agent, the diminishment of the BL signal was linked directly to the number of killed bacterial cells. The method provided a very convenient application, especially when compared to conventional plate counting assays. This novel real-time based method was utilized in both immunological and toxicological assessments. The parameters such as the activation phase, the lytic phase and the capacity of the killing of the serum complement system were specified not only in humans but also in other species. E. coli-lux was also successfully used to study the antimicrobial activities of insect haemolymph. The mechanisms of neutrophil activity, like that of a myeloperoxidase (MPO)-H2O2-halide system, were studied using the E. coli-lux approach. The fundamental role of MPO was challenged, since during the actual killing in described circumstances in phagolysosome the MPO system was inactivated and chlorination halted. The toxicological test system, assessing indoor air total toxicity, particularly suitable for suspected mold damages, was designed based on the E. coli-lux method. Susceptibility to the vast number of various toxins, both pure chemicals and dust samples from the buildings and extracts from molds, were investigated. The E. coli-lux application was found to possess high sensitivity and specificity attributes. Alongside the analysis system, the sampling kit for indoor dust was engineered based on the swipe stick and the container. The combination of practical specimen collector and convenient analysis system provided accurate toxic data from the dust sample within hours. Neutrophils are good indicators of the pathophysiological state of the individual, and they can be utilized as a toxicological probe due to their ability to emit chemiluminescence (CL). Neutrophils can either be used as probe cells, directly exposed to the agent studied, or they can act as indicators of the whole biological system exposed to the agent. Human neutrophils were exposed to the same toxins as tested with the E. coli-lux system and measured as luminol amplified CL emission. The influence of the toxins on the individuals was investigated by exposing rats with moniliniformin, the mycotoxin commonly present in Finnish grains. The activity of the rat neutrophils was found to decrease significantly during the 28 days of exposure.

Julkisten kansallisten palveluhankintojen tarjouspyyntöjen laatimisen ongelmakohdat

Viime vuosien aikana palveluhankintojen suhteellinen osuus kaikista toteutetuista julkisista hankinnoista on kasvanut Suomessa huomattavasti. Samalla markkinaoikeudessa on käsitelty vuosittain suuri määrä erilaisiin julkisiin hankinta-asioihin liittyviä valituksia. Merkittävä valitusten määrä on seurausta siitä, että julkisissa hankintaprosesseissa tehdään paljon virheitä. Tarjouspyynnön laatiminen on tärkeä hankintaprosessin vaihe, johon hankintayksiköissä tulisi kalliit markkinaoikeuskäsittelyt välttääkseen riittävästi panostaa. Tämän tutkielman tavoitteena oli selvittää, mitkä asiat palveluhankintojen tarjouspyyntöjen laatimisessa tuottavat hankintayksiköille ongelmia. Lisäksi tarkoituksena oli pohtia sekä itse palvelun hankkijaan että julkisten hankintojen lainsäädäntöön liittyviä tekijöitä, joista ongelmat palveluhankintojen tarjouspyyntöjen laatimisessa mahdollisesti johtuvat. Tutkimuksessa tutkimuskohteena olivat 24 markkinaoikeuden vuosina 2012–2014 antamaa hankinta-asioiden ratkaisua, ja tutkimus toteutettiin kvalitatiivisena tutkimuksena tutkimusaineistoa kategorisoimalla ja yhdenmukaistamalla. Tutkielmassa havaittiin, että merkittävin kompastuskivi kansallisten palveluhankintojen tarjouspyyntöjen laatimisessa on tarjouksen vertailuperusteiden asettaminen. Erityisesti laadun vertailuperusteiden tulkinnanvarainen ja epäselvä esittäminen oli yleistä, ja lisäksi merkittävä määrä virheitä tehtiin sekoittamalla tarjoajan soveltuvuusvaatimukset vertailuperusteisiin. Joitakin virheitä tehtiin myös vertailuperusteiden tärkeysjärjestyksen ja suhteellisen painotuksen asettamisessa sekä hankinnan kohteen määrittelyssä. Tutkimustulosten perusteella pääteltiin, että kansallisten palveluhankintojen tarjouspyyntöjen laatimisen ongelmissa on suurimmassa osin kyse hankintayksikön vähäisistä resursseista ja siten heikosta hankintojen suunnittelusta sekä hankintayksiköiden ammattitaidon ja kokemuksen puutteista. Lisäksi joitakin esiintyneitä virheitä voidaan ainakin jossain määrin perustella hankintalainsäädännön monimutkaisuudella ja tulkinnanvaraisuudella.

Pairs trading profitability in the Finnish stock market: A comparison between three methods

Pairs trading is an algorithmic trading strategy that is based on the historical co-movement of two separate assets and trades are executed on the basis of degree of relative mispricing. The purpose of this study is to explore one new and alternative copula-based method for pairs trading. The objective is to find out whether the copula method generates more trading opportunities and higher profits than the more traditional distance and cointegration methods applied extensively in previous empirical studies. Methods are compared by selecting top five pairs from stocks of the large and medium-sized companies in the Finnish stock market. The research period includes years 2006-2015. All the methods are proven to be profitable and the Finnish stock market suitable for pairs trading. However, copula method doesn’t generate more trading opportunities or higher profits than the other methods. It seems that the limitations of the more traditional methods are not too restrictive for this particular sample data.

Generative Part-Based Gabor Object Detector

Object detection is a fundamental task of computer vision that is utilized as a core part in a number of industrial and scientific applications, for example, in robotics, where objects need to be correctly detected and localized prior to being grasped and manipulated. Existing object detectors vary in (i) the amount of supervision they need for training, (ii) the type of a learning method adopted (generative or discriminative) and (iii) the amount of spatial information used in the object model (model-free, using no spatial information in the object model, or model-based, with the explicit spatial model of an object). Although some existing methods report good performance in the detection of certain objects, the results tend to be application specific and no universal method has been found that clearly outperforms all others in all areas. This work proposes a novel generative part-based object detector. The generative learning procedure of the developed method allows learning from positive examples only. The detector is based on finding semantically meaningful parts of the object (i.e. a part detector) that can provide additional information to object location, for example, pose. The object class model, i.e. the appearance of the object parts and their spatial variance, constellation, is explicitly modelled in a fully probabilistic manner. The appearance is based on bio-inspired complex-valued Gabor features that are transformed to part probabilities by an unsupervised Gaussian Mixture Model (GMM). The proposed novel randomized GMM enables learning from only a few training examples. The probabilistic spatial model of the part configurations is constructed with a mixture of 2D Gaussians. The appearance of the parts of the object is learned in an object canonical space that removes geometric variations from the part appearance model. Robustness to pose variations is achieved by object pose quantization, which is more efficient than previously used scale and orientation shifts in the Gabor feature space. Performance of the resulting generative object detector is characterized by high recall with low precision, i.e. the generative detector produces large number of false positive detections. Thus a discriminative classifier is used to prune false positive candidate detections produced by the generative detector improving its precision while keeping high recall. Using only a small number of positive examples, the developed object detector performs comparably to state-of-the-art discriminative methods.

A new heuristic method for solving spatially constrained forest planning problems based on mitigation of infeasibilities radiating outward from a forced choice

[Abstract]

Communicating Cost Information to Design Engineers using an Activity-based Costing Method

This paper analyzes the possibilities of integrating cost information and engineering design. Special emphasis is on finding the potential of using the activity-based costing (ABC) method when formulating cost information for the needs of design engineers. This paper suggests that ABC is more useful than the traditional job order costing, but the negative issue is the fact that ABC models become easily too complicated, i.e. expensive to build and maintain, and difficult to use. For engineering design the most suitable elements of ABC are recognizing activities of the company, constructing acitivity chains, identifying resources, activity and cost drivers, as wellas calculating accurate product costs. ABC systems including numerous cost drivers can become complex. Therefore, a comprehensive ABC based cost information system for the use of design engineers should be considered criticaly. Combining the suitable ideas of ABC with engineering oriented thinking could give competentresults.

Description and implementation of cut calculation-method in a sawmill

Työn tavoitteena oli kuvata ja ottaa käyttöön sahauseräkohtaisen kannattavuuden laskentamenetelmä sahalle, sekä tehdä laskentamalli menetelmän tueksi. Sahauksen peruskäsitteiden jälkeen työssä on esitelty sahan tuotantoprosessi. Tuotantoprosessi on kuvattu kirjallisuuden ja asiantuntijoiden haastattelujen perusteella. Seuraavaksi kartoitettiin hyötyjä ja vaikutuksia, mitä laskentamenetelmältä odotetaan.. Kustannuslaskennan teoriaa selvitettiin kirjallisuuslähteitä käyttäen silmälläpitäen juuri tätä kehitettävää laskentamenetelmää. Lisäksi esiteltiin Uimaharjun sahalla käytettävät ja laskentaan liittyvät laskenta- ja tietojärjestelmät.Nykyisin sahalla ei ole minkäänlaista menetelmää sahauseräkohtaisen tuloksen laskemiseksi. Pienillä muutoksilla sahan tietojärjestelmään ja prosessikoneisiin voidaan sahauserä kuljettaa prosessin läpi niin, että jokaisessa prosessin vaiheessa sille saadaan kohdistettua tuotantotietoa. Eri vaiheista saatua tietoa käyttämällä saadaan tarkasti määritettyä tuotteet, joita sahauserä tuotti ja paljonko tuotantoresursseja tuottamiseen kului. Laskentamalliin syötetään tuotantotietoja ja kustannustietoa ja saadaan vastaukseksi sahauserän taloudellinen tulos.Toimenpide ehdotuksena esitetään lisätutkimusta tuotantotietojen automaattisesta keräämisestä manuaalisen työn ja virheiden poistamiseksi. Suhteellisen pienillä panoksilla voidaan jokaiselle sahauserälle kerätä tuotantotiedot täysin automaattisesti. Lisäksi kehittämäni laskentamallin tilalle tulisi hankkia sovellus, joka käyttäisi paremmin hyväksi nykyisiä tietojärjestelmiä ja poistaisi manuaalisen työvaiheen laskennassa.

Bag-of-Features Approach to Unsupervised Visual Object Categorisation

The large and growing number of digital images is making manual image search laborious. Only a fraction of the images contain metadata that can be used to search for a particular type of image. Thus, the main research question of this thesis is whether it is possible to learn visual object categories directly from images. Computers process images as long lists of pixels that do not have a clear connection to high-level semantics which could be used in the image search. There are various methods introduced in the literature to extract low-level image features and also approaches to connect these low-level features with high-level semantics. One of these approaches is called Bag-of-Features which is studied in the thesis. In the Bag-of-Features approach, the images are described using a visual codebook. The codebook is built from the descriptions of the image patches using clustering. The images are described by matching descriptions of image patches with the visual codebook and computing the number of matches for each code. In this thesis, unsupervised visual object categorisation using the Bag-of-Features approach is studied. The goal is to find groups of similar images, e.g., images that contain an object from the same category. The standard Bag-of-Features approach is improved by using spatial information and visual saliency. It was found that the performance of the visual object categorisation can be improved by using spatial information of local features to verify the matches. However, this process is computationally heavy, and thus, the number of images must be limited in the spatial matching, for example, by using the Bag-of-Features method as in this study. Different approaches for saliency detection are studied and a new method based on the Hessian-Affine local feature detector is proposed. The new method achieves comparable results with current state-of-the-art. The visual object categorisation performance was improved by using foreground segmentation based on saliency information, especially when the background could be considered as clutter.