934 resultados para Dupal anomaly


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The overall purpose of this thesis was to increase the knowledge on the biogeochemistry of rural acid sulphate (AS) soil environments and urban forest ecosystems near small towns in Western Finland. In addition, the potential causal relationship between the distribution of AS soils and geographical occurence of multiple sclerosis (MS) disease was assessed based on a review of existing literature and data. Acid sulphate soils, which occupy an area of approximately 17–24 million hectare worldwide, are regarded as the nastiest soils in the world. Independent of the geographical locality of these soils, they pose a great threat to their surrounding environment if disturbed. The abundant metal-rich acid drainage from Finnish AS soils, which is a result of sulphide oxidation due to artificial farmland drainage, has significant but spatially and temporally variable ecotoxicological impacts on biodiversity and community structure of fish, benthic invertebrates and macrophytes. This has resulted in mass fish kills and even eradication of sensitive fish species in affected waters. Moreover, previous investigations demonstrated significantly enriched concentrations of Co, Ni, Mn and Al, metals which are abundantly mobilised in AS soils, in agricultural crops (timothy grass and oats) and approximately 50 times higher concentrations of Al in cow milk originating from AS soils in Western Finland. Nevertheless, the results presented here demonstrate, in general, relatively moderate metal concentrations in oats and cabbage grown on AS soils in Western Finland, although some of the studied fields showed anomalous values of metals (e.g. Co and Ni) in both the soil and target plants (especially oats), similar to that of the previous investigations. The results indicated that the concentrations of Co, Ni, Mn and Zn in oats and Co and Zn in cabbage were governed by soil geochemistry as these metals were correlated with corresponding concentrations extracted from the soil by NH4Ac-EDTA and NH4Ac, respectively. The concentrations of Cu and Fe in oats and cabbage were uncorrelated to that of the easily soluble concentrations in the soils, suggesting that biological processes (e.g. plant-root processes) overshadow geochemical variation. The concentrations of K and Mg in cabbage, which showed a low spread and were strongly correlated to the NH4Ac extractable contents in the soil, were governed by both the bioavailable fractions in the topsoil and plant-uptake mechanisms. The plant´s ability to regulate its uptake of Ca and P (e.g. through root exudates) seemed to be more important than the influence of soil geochemistry. The distribution of P, K, Ca, Mg, Mn and S within humus, moss and needles in and around small towns was to a high degree controlled by biological cycling, which was indicated by the low correlation coefficients for P, K, Ca, Mg and S between humus and moss, and the low spread of these nutrients in moss and needles. The concentration variations of elements in till are mainly due to natural processes (e.g. intrusions, weathering, mineralogical variations in the bedrock). There was a strong spatial pattern for B in humus, moss and needles, which was suggested to be associated with anthropogenic emissions from nearby town centres. Geogenic dust affected the spatial distribution of Fe and Cr in moss, while natural processes governed the Fe anomaly found in the needles. The spatial accumulation patterns of Zn, Cd, Cu, Ni and Pb in humus and moss were strong and diverse, and related to current industry, the former steel industry, coal combustion, and natural geochemical processes. An intriguing Cu anomaly was found in moss. Since it was located close to a main railway line and because the railway line´s electric cables are made of Cu, it was suggested that the reason for the Cu anomaly is corrosion of these cables. In Western Finland, where AS soils are particularly abundant and enrich the metal concentrations of stream waters, cow milk and to some extent crops, an environmental risk assessment would be motivated to elucidate if the metal dispersion affect human health. Within this context, a topic of concern is the distribution of multiple sclerosis as high MS prevalence rates are found in the main area of AS soils. Regionally, the AS soil type in the Seinäjoki area has been demonstrated to be very severe in terms of metal leaching, this area also shows one of the highest MS rates reported worldwide. On a local scale, these severe AS soil types coincide well with the corresponding MS clustering along the Kyrönjoki River in Seinäjoki. There are reasons to suspect that these spatial correlations are causal, as multiple sclerosis has been suggested to result from a combination of genetic and environmental factors.

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Tutkielmassa lähestytään osakemarkkinoilla havaittua poikkeavuutta, momentum-anomaliaa, sekä sen ilmenemistä ja selittyvyyttä Yhdysvaltojen osakemarkkinoiden olosuhteissa. Lisäksi tutkielma sisältää lyhyen katsauksen kansainvälisesti ilmenevään momentumiin kuin myös sen muodostumiseen vaikuttaviin tekijöihin. Työn tutkimusongelmana on, selittyykö Yhdysvaltojen osakemarkkinoilla ilmenevä momentum-anomalia selkeämmin behaviorististen vai makrotaloudellisten riskitekijöiden muodostamien mallien avulla. Kuten aiempi tutkimus on havainnut, myös tässä tutkielmassa oletuksena on, että behavioristis-perusteiset tekijät omaavat suuremman selitysvoiman, kuin makrotaloudellisten riskitekijöiden -perusteiset mallit. Yksittäisiin tekijöihin keskittymisen ohella on tarkoitus havainnoida momentum-anomalian ilmentymisen riippuvuus markkinasuhdanteista, jolloin syntyviä momentumin tuottoja tarkastellaan sekä korkea-, että matalasuhdannemarkkinoiden olosuhteissa.

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The authors report a case of an one-year-old girl with growth retardation, vomiting, aspiration pneumonias and malnutrition presenting gastroesopheal reflux and microgastria. The child was underwent a double lumen Roux-en-Y jejunal reservoir (Hunt-Lawrence pouch). This treatment improved nutritional status and growth. No others anomalies were detected. Congenital microgastria is a rare anomaly which is usually associated with other malformations. The authors reviewed the literature and recommend the gastric augmentation for the treatment for microgastria.

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Our objective is to report a case of laparoscopic cholecystectomy in a patient with duplicated cystic duct. A 34 year old male presented with episodic pain in the upper rigth quadrant of the abdomen. Murphy' s sign was not present. Ultrassonography showed gallbladder with multiple calculi and a thickened wall. At laparoscopic cholecystectomy, a duplicated cystic duct was found. Careful dissection and intraoperative cholangiography were performed to rule out common bile duct injury.

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Living related liver transplantation is being increasingly used for patients that can not wait for a cadaveric organ. We describe a case of a right lobe donor who had a type III portal vein anomaly. On this anomaly the portal vein gives branches first to the right posterior vein and then to the right anterior vein and the left portal vein. The recipient had portal vein thrombosis that was recognized only during the surgery. The Doppler examination performed before the operation did not detect this thrombosis. The transplant was not accomplished. Anatomical anomaly of the portal vein may be a rare cause impossibility to organ donation in living related liver transplantation.

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Urethral duplication is a rare congenital anomaly. The clinical presentation and treatment varies because of the different anatomical patterns of this abnormality. We report a case of this entity in the adult male patient. The clinical, radiological and endoscopic findings, as well as the treatment are discussed.

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Urachus anomalies are generally asymptomatic, but when infected can simulate acute abdomen. This anomaly has to be deemed when abdominal tenderness is associated with inflammation signs in parumbilical or hypogastric regions. Ultrasonography has great sensibility to settle down the diagnosis as observed from our three cases. Ultrasonography images with air suggest intestinal fistula in most cases with sigmoid or ileum as shown here.

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Fraud is an increasing phenomenon as shown in many surveys carried out by leading international consulting companies in the last years. Despite the evolution of electronic payments and hacking techniques there is still a strong human component in fraud schemes. Conflict of interest in particular is the main contributing factor to the success of internal fraud. In such cases anomaly detection tools are not always the best instruments, since the fraud schemes are based on faking documents in a context dominated by lack of controls, and the perpetrators are those ones who should control possible irregularities. In the banking sector audit team experts can count only on their experience, whistle blowing and the reports sent by their inspectors. The Fraud Interactive Decision Expert System (FIDES), which is the core of this research, is a multi-agent system built to support auditors in evaluating suspicious behaviours and to speed up the evaluation process in order to detect or prevent fraud schemes. The system combines Think-map, Delphi method and Attack trees and it has been built around audit team experts and their needs. The output of FIDES is an attack tree, a tree-based diagram to ”systematically categorize the different ways in which a system can be attacked”. Once the attack tree is built, auditors can choose the path they perceive as more suitable and decide whether or not to start the investigation. The system is meant for use in the future to retrieve old cases in order to match them with new ones and find similarities. The retrieving features of the system will be useful to simplify the risk management phase, since similar countermeasures adopted for past cases might be useful for present ones. Even though FIDES has been built with the banking sector in mind, it can be applied in all those organisations, like insurance companies or public organizations, where anti-fraud activity is based on a central anti-fraud unit and a reporting system.

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Tämä kandidaatintutkielma käsittelee yrityksen kokoon ja book-to-market arvoon perustuvia anomalioita Yhdysvaltojen osakemarkkinoilla. Tutkimuksen kohteena on epänormaalien tuottojen saavuttaminen kyseisten anomalioiden kautta erityisesti finanssikriisin aikana. Osakeportfolioiden analysointi tapahtuu pääasiassa Fama-French kolmifaktorimallin avulla.

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The objective of the present study was to determine the frequency of somatic chromosomal anomalies and Y chromosomal microdeletions (azoospermia factor genes, AZF) in infertile males who seek assisted reproduction. These studies are very important because the assisted reproduction techniques (mainly intracytoplasmic sperm injection) bypass the natural selection process and some classical chromosomal abnormalities, microdeletions of AZF genes or some deleterious genic mutations could pass through generations. These genetic abnormalities can cause in the offspring of these patients male infertility, ambiguous external genitalia, mental retardation, and other birth defects. We studied 165 infertile men whose infertility was attributable to testicular problems (60 were azoospermic, 100 were oligospermic and 5 were asthenospermic). We studied 100 metaphases per patient with GTG banding obtained from temporary lymphocyte culture for chromosomal abnormality detection and performed a genomic DNA analysis using 28 Y chromosome-specific sequence-tagged sites for Y AZF microdeletion detection. Karyotyping revealed somatic anomalies in 16 subjects (16/165 = 9.6%). Of these 16, 12 were in the azoospermic group (12/60 = 20%) and 4 were in the oligospermic group (4/100 = 4%). The most common chromosomal anomaly was Klinefelter syndrome (10/165 = 6%). Microdeletions of AZF genes were detected in 12 subjects (12/160 = 7.5%). The frequencies detected are similar to those described previously. These results show the importance of genetic evaluation of infertile males prior to assisted reproduction. Such evaluation can lead to genetic counseling and, consequently, to primary and secondary prevention of mental retardation and birth defects.

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It has been reported that, compared with simple increased nuchal translucency, fetal cases with septated cystic hygroma (CH) are more likely to face perinatal handicaps. However, pediatric outcomes and proper prenatal counseling for this anomaly have not yet been truly defined. We performed this study to determine pregnancy and pediatric outcomes of fetuses with septated CH. We searched records for cases with septated CH and collected data for structural abnormalities, karyotype analysis, and pregnancy outcomes. Fetuses born with septated CH were also evaluated for their pediatric outcomes. Sixty-nine fetuses with septated CH were enrolled in the study. Results showed that chromosomal abnormalities were present in 28 fetuses (40.6%), and the most common aneuploidy was Turner syndrome (n=14, 20.3%); 16 (23.2%) of the remaining cases, in which aneuploidy was not found, had coexistent structural malformations; 25 (36.2%) cases had normal karyotype and morphology. The total number of live births and infants with unfavorable neurologic follow-up were 13 (18.8%) and 2 (2.9%), respectively. Septated CH is associated with poor perinatal outcomes; therefore, karyotype analysis and ultrasonographic anomaly screening should be performed as initial steps, and expectant management should be offered to couples with euploid fetuses that have normal morphology.

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Alhaisen volatiliteetin anomalian mukaan sijoittajan on mahdollista saada korkeaa tuottoa alhaisella riskillä, mikä on sijoitusstrategina mielenkiintoinen, koska modernin rahoitusteorian mukaan korkeat tuotot saavutetaan vain riskiä kasvattamalla. Tässä tutkielmassa selvitettiin alhaisen volatiliteetin ja korkean idiosynkraattisen riskin anomalioiden olemassaoloa Suomen osakemarkkinoilla sekä institutionaalisen sijoittajan mahdollisuuksia hyödyntää tutkittuja anomalioita. Tutkimusaineisto large cap -osakkeilla vuosilta 2000-2013 osoittaa, että sijoittamalla alhaisen volatiliteetin osakkeisiin sijoittaja on pystynyt voittamaan absoluuttisella tuotolla mitattuna OMXH CAP-indeksin, muttei saavuttamaan riskikorjattuja ylituottoja. Alhaisen volatiliteetin osakkeiden suoriutumista on selitetty useilla tekijöillä kuten sijoittajien irrationaalisella käyttäytymisellä näiden suosiessa korkean volatiliteetin osakkeita painaen alas samalla näiden tuottopotentiaalia. Toiseksi, alhaisen volatiliteetin yrityksillä on vahvat fundamentit, joiden myötä liikevoitto sekä tulos pysyvät vahvoina, joka näkyy puolestaan hyvinä osaketuottoina. Lisäksi, institutionaaliselle sijoittajalle muodostuu esteitä sijoittaa vain alhaisen volatiliteetin osakkeisiin, mikä osaltaan estää anomalian pois pyyhkiytymisen. Idiosynkraattisen riskin anomaliaa ei voitu todentaa käytettäessä FF3-mallin residuaaleja. Anomaliaa tutkittiin historiallista sekä EGARCH-mallilla ennustettua idiosynkraattista riskiä käyttäen.

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This thesis discusses the basic problem of the modern portfolio theory about how to optimise the perfect allocation for an investment portfolio. The theory provides a solution for an efficient portfolio, which minimises the risk of the portfolio with respect to the expected return. A central feature for all the portfolios on the efficient frontier is that the investor needs to provide the expected return for each asset. Market anomalies are persistent patterns seen in the financial markets, which cannot be explained with the current asset pricing theory. The goal of this thesis is to study whether these anomalies can be observed among different asset classes. Finally, if persistent patterns are found, it is investigated whether the anomalies hold valuable information for determining the expected returns used in the portfolio optimization Market anomalies and investment strategies based on them are studied with a rolling estimation window, where the return for the following period is always based on historical information. This is also crucial when rebalancing the portfolio. The anomalies investigated within this thesis are value, momentum, reversal, and idiosyncratic volatility. The research data includes price series of country level stock indices, government bonds, currencies, and commodities. The modern portfolio theory and the views given by the anomalies are combined by utilising the Black-Litterman model. This makes it possible to optimise the portfolio so that investor’s views are taken into account. When constructing the portfolios, the goal is to maximise the Sharpe ratio. Significance of the results is studied by assessing if the strategy yields excess returns in a relation to those explained by the threefactormodel. The most outstanding finding is that anomaly based factors include valuable information to enhance efficient portfolio diversification. When the highest Sharpe ratios for each asset class are picked from the test factors and applied to the Black−Litterman model, the final portfolio results in superior riskreturn combination. The highest Sharpe ratios are provided by momentum strategy for stocks and long-term reversal for the rest of the asset classes. Additionally, a strategy based on the value effect was highly appealing, and it basically performs as well as the previously mentioned Sharpe strategy. When studying the anomalies, it is found, that 12-month momentum is the strongest effect, especially for stock indices. In addition, a high idiosyncratic volatility seems to be positively correlated with country indices on stocks.

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Tutkimuksen tavoitteena on tutkia tammikuu- ja kuunvaihdeanomalian esiintymistä Suomen osakemarkkinoilla.